Datasets:

liesvarastranta

/

arxiv_cs_category

like 3

1911.11686

Ying Huang

Ying Huang, Jiankai Zhuang, Zengchang Qin

Multi-Level Network for High-Speed Multi-Person Pose Estimation

5 pages, published at ICIP 2019

cs.CV

http://creativecommons.org/licenses/by-nc-sa/4.0/

In multi-person pose estimation, the left/right joint type discrimination is always a hard problem because of the similar appearance. Traditionally, we solve this problem by stacking multiple refinement modules to increase network's receptive fields and capture more global context, which can also increase a great amount of computation. In this paper, we propose a Multi-level Network (MLN) that learns to aggregate features from lower-level (left/right information), upper-level (localization information), joint-limb level (complementary information) and global-level (context) information for discrimination of joint type. Through feature reuse and its intra-relation, MLN can attain comparable performance to other conventional methods while runtime speed retains at 42.2 FPS.

[{'version': 'v1', 'created': 'Tue, 26 Nov 2019 16:42:46 GMT'}]

2019-11-27

[['Huang', 'Ying', ''], ['Zhuang', 'Jiankai', ''], ['Qin', 'Zengchang', '']]

1908.05886

Joydip Sengupta

Joydip Sengupta, R.K.Sahoo, K.K.Bardhan, C.D.Mukherjee

Influence of annealing temperature on the structural, topographical and optical properties of sol gel derived ZnO thin films

Zinc oxide thin film, Sol gel preparation, Annealing X ray diffraction, Atomic force microscopy, Optical properties

Materials Letters Volume 65, Issues 17_18, September 2011, Pages 2572_2574

10.1016/j.matlet.2011.06.021

physics.app-ph cond-mat.mtrl-sci

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

This investigation deals with the effect of annealing temperature on the structural, topographical and optical properties of Zinc Oxide thin films prepared by sol gel method. The structural properties were studied using X-ray diffraction and the recorded patterns indicated that all the films had a preferred orientation along (002) plane and the crystallinity along with the grain size were augmented with annealing temperature. The topographical modification of the films due to heat treatment was probed by atomic force microscopy which revealed that annealing roughened the surface of the film. The optical properties were examined by a UV visible spectrophotometer which exhibited that maximum transmittance reached nearly 90% and it diminished with increasing annealing temperature.

[{'version': 'v1', 'created': 'Fri, 16 Aug 2019 08:33:44 GMT'}]

2019-08-19

[['Sengupta', 'Joydip', ''], ['Sahoo', 'R. K.', ''], ['Bardhan', 'K. K.', ''], ['Mukherjee', 'C. D.', '']]

1606.09082

Stefan Thurner

Ivan Smirnov and Stefan Thurner

Formation of homophily in academic performance: students prefer to change their friends rather than performance

10.1371/journal.pone.0183473

physics.soc-ph cs.SI

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Homophily, the tendency of individuals to associate with others who share similar traits, has been identified as a major driving force in the formation and evolution of social ties. In many cases, it is not clear if homophily is the result of a socialization process, where individuals change their traits according to the dominance of that trait in their local social networks, or if it results from a selection process, in which individuals reshape their social networks so that their traits match those in the new environment. Here we demonstrate the detailed temporal formation of strong homophily in academic achievements of high school and university students. We analyze a unique dataset that contains information about the detailed time evolution of a friendship network of 6,000 students across 42 months. Combining the evolving social network data with the time series of the academic performance (GPA) of individual students, we show that academic homophily is a result of selection: students prefer to gradually reorganize their social networks according to their performance levels, rather than adapting their performance to the level of their local group. We find no signs for a pull effect, where a social environment of good performers motivates bad students to improve their performance. We are able to understand the underlying dynamics of grades and networks with a simple model. The lack of a social pull effect in classical educational settings could have important implications for the understanding of the observed persistence of segregation, inequality and social immobility in societies.

[{'version': 'v1', 'created': 'Wed, 29 Jun 2016 13:24:45 GMT'}]

2017-09-01

[['Smirnov', 'Ivan', ''], ['Thurner', 'Stefan', '']]

2206.12402

Florian Lalande

Florian Lalande and Alessandro Alberto Trani

Predicting the Stability of Hierarchical Triple Systems with Convolutional Neural Networks

12 pages, 6 figures, accepted for publication in ApJ

10.3847/1538-4357/ac8eab

astro-ph.SR astro-ph.EP cs.LG math.DS

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Understanding the long-term evolution of hierarchical triple systems is challenging due to its inherent chaotic nature, and it requires computationally expensive simulations. Here we propose a convolutional neural network model to predict the stability of hierarchical triples by looking at their evolution during the first $5 \times 10^5$ inner binary orbits. We employ the regularized few-body code TSUNAMI to simulate $5\times 10^6$ hierarchical triples, from which we generate a large training and test dataset. We develop twelve different network configurations that use different combinations of the triples' orbital elements and compare their performances. Our best model uses 6 time-series, namely, the semimajor axes ratio, the inner and outer eccentricities, the mutual inclination and the arguments of pericenter. This model achieves an area under the curve of over $95\%$ and informs of the relevant parameters to study triple systems stability. All trained models are made publicly available, allowing to predict the stability of hierarchical triple systems $200$ times faster than pure $N$-body methods.

[{'version': 'v1', 'created': 'Fri, 24 Jun 2022 17:58:13 GMT'}, {'version': 'v2', 'created': 'Thu, 1 Sep 2022 04:30:29 GMT'}]

2022-10-26

[['Lalande', 'Florian', ''], ['Trani', 'Alessandro Alberto', '']]

1807.04861

Vitaliy Batusov

Vitaliy Batusov, Giuseppe De Giacomo, Mikhail Soutchanski

Hybrid Temporal Situation Calculus

cs.AI

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The ability to model continuous change in Reiter's temporal situation calculus action theories has attracted a lot of interest. In this paper, we propose a new development of his approach, which is directly inspired by hybrid systems in control theory. Specifically, while keeping the foundations of Reiter's axiomatization, we propose an elegant extension of his approach by adding a time argument to all fluents that represent continuous change. Thereby, we insure that change can happen not only because of actions, but also due to the passage of time. We present a systematic methodology to derive, from simple premises, a new group of axioms which specify how continuous fluents change over time within a situation. We study regression for our new temporal basic action theories and demonstrate what reasoning problems can be solved. Finally, we formally show that our temporal basic action theories indeed capture hybrid automata.

[{'version': 'v1', 'created': 'Thu, 12 Jul 2018 23:20:11 GMT'}]

2018-07-16

[['Batusov', 'Vitaliy', ''], ['De Giacomo', 'Giuseppe', ''], ['Soutchanski', 'Mikhail', '']]

2202.01677

Michael Heider

Michael Heider, Helena Stegherr, Jonathan Wurth, Roman Sraj, J\"org H\"ahner

Separating Rule Discovery and Global Solution Composition in a Learning Classifier System

Genetic and Evolutionary Computation Conference Companion (GECCO '22 Companion), July 9--13, 2022, Boston, MA, USA

10.1145/3520304.3529014

cs.LG cs.AI cs.NE

http://creativecommons.org/licenses/by-nc-nd/4.0/

While utilization of digital agents to support crucial decision making is increasing, trust in suggestions made by these agents is hard to achieve. However, it is essential to profit from their application, resulting in a need for explanations for both the decision making process and the model. For many systems, such as common black-box models, achieving at least some explainability requires complex post-processing, while other systems profit from being, to a reasonable extent, inherently interpretable. We propose a rule-based learning system specifically conceptualised and, thus, especially suited for these scenarios. Its models are inherently transparent and easily interpretable by design. One key innovation of our system is that the rules' conditions and which rules compose a problem's solution are evolved separately. We utilise independent rule fitnesses which allows users to specifically tailor their model structure to fit the given requirements for explainability.

[{'version': 'v1', 'created': 'Thu, 3 Feb 2022 16:45:05 GMT'}, {'version': 'v2', 'created': 'Mon, 18 Apr 2022 20:07:32 GMT'}]

2022-04-21

[['Heider', 'Michael', ''], ['Stegherr', 'Helena', ''], ['Wurth', 'Jonathan', ''], ['Sraj', 'Roman', ''], ['Hähner', 'Jörg', '']]

1805.08449

Kensuke Harada

Kensuke Harada, Weiwei Wan, Tokuo Tsuji, Kohei Kikuchi, Kazuyuki Nagata, and Hiromu Onda

Experiments on Learning Based Industrial Bin-picking with Iterative Visual Recognition

This paper is to appear Industrial Robots: an International Journal

Industrial Robots: an International Journal, 2018

cs.RO

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

This paper shows experimental results on learning based randomized bin-picking combined with iterative visual recognition. We use the random forest to predict whether or not a robot will successfully pick an object for given depth images of the pile taking the collision between a finger and a neighboring object into account. For the discriminator to be accurate, we consider estimating objects' poses by merging multiple depth images of the pile captured from different points of view by using a depth sensor attached at the wrist. We show that, even if a robot is predicted to fail in picking an object with a single depth image due to its large occluded area, it is finally predicted as success after merging multiple depth images. In addition, we show that the random forest can be trained with the small number of training data.

[{'version': 'v1', 'created': 'Tue, 22 May 2018 08:21:45 GMT'}]

2018-05-23

[['Harada', 'Kensuke', ''], ['Wan', 'Weiwei', ''], ['Tsuji', 'Tokuo', ''], ['Kikuchi', 'Kohei', ''], ['Nagata', 'Kazuyuki', ''], ['Onda', 'Hiromu', '']]

2207.08109

Tatsuya Chuman

Tatsuya Chuman, Hitoshi Kiya

Security Evaluation of Compressible Image Encryption for Privacy-Preserving Image Classification against Ciphertext-only Attacks

To be appeared in International Conference on Machine Learning and Cybernetics 2022

cs.CR

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The security of learnable image encryption schemes for image classification using deep neural networks against several attacks has been discussed. On the other hand, block scrambling image encryption using the vision transformer has been proposed, which applies to lossless compression methods such as JPEG standard by dividing an image into permuted blocks. Although robustness of the block scrambling image encryption against jigsaw puzzle solver attacks that utilize a correlation among the blocks has been evaluated under the condition of a large number of encrypted blocks, the security of encrypted images with a small number of blocks has never been evaluated. In this paper, the security of the block scrambling image encryption against ciphertext-only attacks is evaluated by using jigsaw puzzle solver attacks.

[{'version': 'v1', 'created': 'Sun, 17 Jul 2022 08:34:56 GMT'}]

2022-07-19

[['Chuman', 'Tatsuya', ''], ['Kiya', 'Hitoshi', '']]

1806.05722

Samet Oymak

Samet Oymak and Necmiye Ozay

Non-asymptotic Identification of LTI Systems from a Single Trajectory

Version 2 has two improvements: First, paper now uses spectral radius rather than largest singular value hence applies to a larger class of systems. Secondly, new sample complexity bounds are provided for approximating the system's Hankel operator via estimated Markov parameters

cs.LG cs.SY math.OC stat.ML

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

We consider the problem of learning a realization for a linear time-invariant (LTI) dynamical system from input/output data. Given a single input/output trajectory, we provide finite time analysis for learning the system's Markov parameters, from which a balanced realization is obtained using the classical Ho-Kalman algorithm. By proving a stability result for the Ho-Kalman algorithm and combining it with the sample complexity results for Markov parameters, we show how much data is needed to learn a balanced realization of the system up to a desired accuracy with high probability.

[{'version': 'v1', 'created': 'Thu, 14 Jun 2018 20:05:25 GMT'}, {'version': 'v2', 'created': 'Sun, 3 Feb 2019 23:44:44 GMT'}]

2019-02-05

[['Oymak', 'Samet', ''], ['Ozay', 'Necmiye', '']]

2205.06905

Valerie Chen

Valerie Chen, Umang Bhatt, Hoda Heidari, Adrian Weller, Ameet Talwalkar

Perspectives on Incorporating Expert Feedback into Model Updates

cs.LG

http://creativecommons.org/licenses/by/4.0/

Machine learning (ML) practitioners are increasingly tasked with developing models that are aligned with non-technical experts' values and goals. However, there has been insufficient consideration on how practitioners should translate domain expertise into ML updates. In this paper, we consider how to capture interactions between practitioners and experts systematically. We devise a taxonomy to match expert feedback types with practitioner updates. A practitioner may receive feedback from an expert at the observation- or domain-level, and convert this feedback into updates to the dataset, loss function, or parameter space. We review existing work from ML and human-computer interaction to describe this feedback-update taxonomy, and highlight the insufficient consideration given to incorporating feedback from non-technical experts. We end with a set of open questions that naturally arise from our proposed taxonomy and subsequent survey.

[{'version': 'v1', 'created': 'Fri, 13 May 2022 21:46:55 GMT'}, {'version': 'v2', 'created': 'Sat, 16 Jul 2022 18:55:54 GMT'}]

2022-07-19

[['Chen', 'Valerie', ''], ['Bhatt', 'Umang', ''], ['Heidari', 'Hoda', ''], ['Weller', 'Adrian', ''], ['Talwalkar', 'Ameet', '']]

2101.05891

Sajila Wickramaratne

Sajila D. Wickramaratne and Md Shaad Mahmud

A Deep Learning Based Ternary Task Classification System Using Gramian Angular Summation Field in fNIRS Neuroimaging Data

4 pages, 4 Figures

cs.LG

http://creativecommons.org/licenses/by/4.0/

Functional near-infrared spectroscopy (fNIRS) is a non-invasive, economical method used to study its blood flow pattern. These patterns can be used to classify tasks a subject is performing. Currently, most of the classification systems use simple machine learning solutions for the classification of tasks. These conventional machine learning methods, which are easier to implement and interpret, usually suffer from low accuracy and undergo a complex preprocessing phase before network training. The proposed method converts the raw fNIRS time series data into an image using Gramian Angular Summation Field. A Deep Convolutional Neural Network (CNN) based architecture is then used for task classification, including mental arithmetic, motor imagery, and idle state. Further, this method can eliminate the feature selection stage, which affects the traditional classifiers' performance. This system obtained 87.14% average classification accuracy higher than any other method for the dataset.

[{'version': 'v1', 'created': 'Thu, 14 Jan 2021 22:09:35 GMT'}]

2021-01-18

[['Wickramaratne', 'Sajila D.', ''], ['Mahmud', 'Md Shaad', '']]

1906.01530

Janosch Haber

Janosch Haber, Tim Baumg\"artner, Ece Takmaz, Lieke Gelderloos, Elia Bruni and Raquel Fern\'andez

The PhotoBook Dataset: Building Common Ground through Visually-Grounded Dialogue

Updates 26-06-2019: Changed caption sizes to comply with the ACL style guidelines and corrected some references

cs.CL cs.AI cs.CV

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

This paper introduces the PhotoBook dataset, a large-scale collection of visually-grounded, task-oriented dialogues in English designed to investigate shared dialogue history accumulating during conversation. Taking inspiration from seminal work on dialogue analysis, we propose a data-collection task formulated as a collaborative game prompting two online participants to refer to images utilising both their visual context as well as previously established referring expressions. We provide a detailed description of the task setup and a thorough analysis of the 2,500 dialogues collected. To further illustrate the novel features of the dataset, we propose a baseline model for reference resolution which uses a simple method to take into account shared information accumulated in a reference chain. Our results show that this information is particularly important to resolve later descriptions and underline the need to develop more sophisticated models of common ground in dialogue interaction.

[{'version': 'v1', 'created': 'Tue, 4 Jun 2019 15:41:32 GMT'}, {'version': 'v2', 'created': 'Wed, 26 Jun 2019 17:36:47 GMT'}]

2019-06-27

[['Haber', 'Janosch', ''], ['Baumgärtner', 'Tim', ''], ['Takmaz', 'Ece', ''], ['Gelderloos', 'Lieke', ''], ['Bruni', 'Elia', ''], ['Fernández', 'Raquel', '']]

1810.10973

Maryam Salim

Maryam Salim, Ali Caglar Ozen, Michael Bock, Ergin Atalar

Active Decoupling of Transmit and Receive Coils for Full-Duplex MRI

physics.med-ph eess.IV eess.SP

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Objective: Concurrent excitation and acquisition in MRI is a method to acquire MRI signal from tissues with very short transverse relaxation time. Since transmit power is many orders of magnitude larger than receive signal, a weak coupling dominates the MR signal during CEA. Thus, appropriate decoupling between transmit and receive coils is required. In this study, two controllable decoupling designs are investigated for achieving isolation between coils. Methods: A modified version of isolation concept used in the full-duplex radios in communication systems is applied to acquire MRI signal using CEA. In our new method, a small copy of RF transmit signal is attenuated and delayed to generate the same coupling signal which is available in the receiver coil. Then it is subtracted from the receive signal to detect the MRI signal. The proposed decoupling method is developed and implemented in two designs: Semi-Automatic and Fully-Automatic Controllable Decoupling Designs. Results: Using Semi-Automatic Controllable Decoupling Design, decoupling of more than 75 dB is achieved. Fully-Automatic Controllable Decoupling Design provides more than 100 dB decoupling between coils which is good enough for detecting MRI signals during excitation from tissues with very short transverse relaxation time. Conclusion: This study shows feasibility of applying full duplex electronics to decouple transmit and receive coils for CEA in a clinical MRI system. Significance: These designs can automatically tune the cancellation circuit and it is a potential tool for recovering signal from tissues with very short T2 in clinical MR systems with a minor hardware modification.

[{'version': 'v1', 'created': 'Mon, 22 Oct 2018 02:02:23 GMT'}]

2018-10-26

[['Salim', 'Maryam', ''], ['Ozen', 'Ali Caglar', ''], ['Bock', 'Michael', ''], ['Atalar', 'Ergin', '']]

2210.11691

Kaiyuan Chen

Kaiyuan Chen, Jiachen Yuan, Nikhil Jha, Jeffrey Ichnowski, John Kubiatowicz, Ken Goldberg

FogROS G: Enabling Secure, Connected and Mobile Fog Robotics with Global Addressability

5 pages, 5 figures. Published at IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) 2022 Cloud Robotics Workshop

cs.RO

http://creativecommons.org/licenses/by/4.0/

Fog Robotics renders networked robots with greater mobility, on-demand compute capabilities and better energy efficiency by offloading heavy robotics workloads to nearby Edge and distant Cloud data centers. However, as the de-facto standard for implementing fog robotics applications, Robot Operating System (ROS) and its successor ROS2 fail to provide fog robots with a mobile-friendly and secure communication infrastructure. In this work, we present FogROS G, a secure routing framework that connects robotics software components from different physical locations, networks, Data Distribution Service (DDS) and ROS distributions. FogROS G indexes networked robots with globally unique 256-bit names that remains constant even if the robot roams between multiple administrative network domains. FogROS G leverages Global Data Plane, a global and secure peer-to-peer routing infrastructure between the names, guaranteeing that only authenticated party can send to or receive from the robot. FogROS G adopts a proxy-based design that connect nodes from ROS1 and ROS2 with mainstream DDS vendors; this can be done without any changes to the application code.

[{'version': 'v1', 'created': 'Fri, 21 Oct 2022 02:31:33 GMT'}]

2022-10-24

[['Chen', 'Kaiyuan', ''], ['Yuan', 'Jiachen', ''], ['Jha', 'Nikhil', ''], ['Ichnowski', 'Jeffrey', ''], ['Kubiatowicz', 'John', ''], ['Goldberg', 'Ken', '']]

1910.08268

Kangning Ma

Kangning Ma, Shuo Shao

Secure Coded Caching with Colluding Users

cs.IT math.IT

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

In a secure coded caching system, a central server balances the traffic flow between peak and off-peak periods by distributing some public data to the users' caches in advance. Meanwhile, these data are securely protected against the possible colluding users, who might share their cache. We model the system as a flow network and study its capacity region via a network information-theoretic approach. Due to the difficulty of characterizing the capacity region straightforwardly, our approach is two folded from the perspective of network information theory. On one hand, we identify the inner bound of capacity region by proposing a coded caching scheme to achieve a low load secure data transmission. On the other hand, we also establish outer outer bounds on the capacity region, which show that our proposed scheme is order optimal in general under specific circumstance.

[{'version': 'v1', 'created': 'Fri, 18 Oct 2019 05:15:09 GMT'}]

2019-10-21

[['Ma', 'Kangning', ''], ['Shao', 'Shuo', '']]

2106.13550

Sergey Kirgizov S.

Jean-Luc Baril, Sergey Kirgizov, and Vincent Vajnovszki

Asymptotic bit frequency in Fibonacci words

8 pages, 3 figures

math.CO cs.DM

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

It is known that binary words containing no $k$ consecutive 1s are enumerated by $k$-step Fibonacci numbers. In this note we discuss the expected value of a random bit in a random word of length $n$ having this property.

[{'version': 'v1', 'created': 'Fri, 25 Jun 2021 10:51:48 GMT'}, {'version': 'v2', 'created': 'Fri, 6 May 2022 09:20:19 GMT'}]

2022-05-09

[['Baril', 'Jean-Luc', ''], ['Kirgizov', 'Sergey', ''], ['Vajnovszki', 'Vincent', '']]

1606.01431

Quang V Nguyen

Quang V Nguyen, Mary Tate, Philip Calvert and Benoit Aubert

Leveraging ERP Implementation to Create Intellectual Capital: the Role of Organizational Learning Capability

ISBN# 978-0-646-95337-3 Presented at the Australasian Conference on Information Systems 2015 (arXiv:1605.01032)

ACIS/2015/131

cs.OH

http://creativecommons.org/licenses/by-nc-sa/4.0/

The extent to which enterprise resource planning (ERP) systems deliver value for organizations has been debated. In this study, we argue that the presence of appropriate organizational resources is essential for capturing the potential of ERP implementation. We investigate the relationship between ERP implementation and two organizational resources, specifically, Intellectual Capital (IC) and Organizational Learning Capability (OLC) to enrich the understanding of the way the value of ERP implementations can be realized. A sample of 226 manufacturing firms in Vietnam was surveyed to test the theoretical model. Structural equation modelling with partial least square method and two approaches for moderation analysis were used to analyze the data. The results indicate that ERP implementation scope has a positive impact on intellectual capital (IC). However, firms need to build a certain level of OLC to utilize ERP implementation for the enhancement of IC.

[{'version': 'v1', 'created': 'Sat, 4 Jun 2016 23:12:17 GMT'}]

2016-06-07

[['Nguyen', 'Quang V', ''], ['Tate', 'Mary', ''], ['Calvert', 'Philip', ''], ['Aubert', 'Benoit', '']]

2207.07689

Alexandr Sboev

Alexander G. Sboev, Nikolay A. Kudryshov, Ivan A. Moloshnikov, Saveliy V. Zavertyaev, Aleksandr V. Naumov and Roman B. Rybka

Strict baselines for Covid-19 forecasting and ML perspective for USA and Russia

cs.LG cs.AI

http://creativecommons.org/licenses/by-nc-nd/4.0/

Currently, the evolution of Covid-19 allows researchers to gather the datasets accumulated over 2 years and to use them in predictive analysis. In turn, this makes it possible to assess the efficiency potential of more complex predictive models, including neural networks with different forecast horizons. In this paper, we present the results of a consistent comparative study of different types of methods for predicting the dynamics of the spread of Covid-19 based on regional data for two countries: the United States and Russia. We used well-known statistical methods (e.g., Exponential Smoothing), a "tomorrow-as-today" approach, as well as a set of classic machine learning models trained on data from individual regions. Along with them, a neural network model based on Long short-term memory (LSTM) layers was considered, the training samples of which aggregate data from all regions of two countries: the United States and Russia. Efficiency evaluation was carried out using cross-validation according to the MAPE metric. It is shown that for complicated periods characterized by a large increase in the number of confirmed daily cases, the best results are shown by the LSTM model trained on all regions of both countries, showing an average Mean Absolute Percentage Error (MAPE) of 18%, 30%, 37% for Russia and 31%, 41%, 50% for US for predictions at forecast horizons of 14, 28, and 42 days, respectively.

[{'version': 'v1', 'created': 'Fri, 15 Jul 2022 18:21:36 GMT'}]

2022-07-19

[['Sboev', 'Alexander G.', ''], ['Kudryshov', 'Nikolay A.', ''], ['Moloshnikov', 'Ivan A.', ''], ['Zavertyaev', 'Saveliy V.', ''], ['Naumov', 'Aleksandr V.', ''], ['Rybka', 'Roman B.', '']]

1903.00870

Tiangang Cui

Johnathan Bardsley and Tiangang Cui and Youssef Marzouk and Zheng Wang

Scalable optimization-based sampling on function space

stat.CO cs.NA math.NA stat.ME

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Optimization-based samplers such as randomize-then-optimize (RTO) [2] provide an efficient and parallellizable approach to solving large-scale Bayesian inverse problems. These methods solve randomly perturbed optimization problems to draw samples from an approximate posterior distribution. "Correcting" these samples, either by Metropolization or importance sampling, enables characterization of the original posterior distribution. This paper focuses on the scalability of RTO to problems with high- or infinite-dimensional parameters. We introduce a new subspace acceleration strategy that makes the computational complexity of RTO scale linearly with the parameter dimension. This subspace perspective suggests a natural extension of RTO to a function space setting. We thus formalize a function space version of RTO and establish sufficient conditions for it to produce a valid Metropolis-Hastings proposal, yielding dimension-independent sampling performance. Numerical examples corroborate the dimension-independence of RTO and demonstrate sampling performance that is also robust to small observational noise.

[{'version': 'v1', 'created': 'Sun, 3 Mar 2019 09:35:36 GMT'}, {'version': 'v2', 'created': 'Mon, 28 Oct 2019 04:15:34 GMT'}]

2019-10-29

[['Bardsley', 'Johnathan', ''], ['Cui', 'Tiangang', ''], ['Marzouk', 'Youssef', ''], ['Wang', 'Zheng', '']]

1611.01607

Wonjae Shin

Wonjae Shin, Mojtaba Vaezi, Byungju Lee, David J. Love, Jungwoo Lee, H. Vincent Poor

Non-Orthogonal Multiple Access in Multi-Cell Networks: Theory, Performance, and Practical Challenges

13 pages, 4 figures, Accepted for publication on IEEE Communications Magazine

cs.IT math.IT

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Non-orthogonal multiple access (NOMA) is a potential enabler for the development of 5G and beyond wireless networks. By allowing multiple users to share the same time and frequency, NOMA can scale up the number of served users, increase the spectral efficiency, and improve user-fairness compared to existing orthogonal multiple access (OMA) techniques. While single-cell NOMA has drawn significant attention recently, much less attention has been given to multi-cell NOMA. This article discusses the opportunities and challenges of NOMA in a multi-cell environment. As the density of base stations and devices increases, inter-cell interference becomes a major obstacle in multi-cell networks. As such, identifying techniques that combine interference management approaches with NOMA is of great significance. After discussing the theory behind NOMA, this paper provides an overview of the current literature and discusses key implementation and research challenges, with an emphasis on multi-cell NOMA.

[{'version': 'v1', 'created': 'Sat, 5 Nov 2016 05:51:58 GMT'}, {'version': 'v2', 'created': 'Thu, 13 Apr 2017 05:31:15 GMT'}]

2017-04-14

[['Shin', 'Wonjae', ''], ['Vaezi', 'Mojtaba', ''], ['Lee', 'Byungju', ''], ['Love', 'David J.', ''], ['Lee', 'Jungwoo', ''], ['Poor', 'H. Vincent', '']]

1904.12673

Anand Vijayakumar Dr

A. Vijayakumar, D. Jayavel, M. Muthaiah, Shanti Bhattacharya, and Joseph Rosen

Implementation of a speckle correlation based optical lever (SC-OptLev) with extended dynamic range

9 pages, 3 figures

10.1364/AO.58.005982

physics.ins-det

http://creativecommons.org/licenses/by/4.0/

A speckle correlation based optical lever (SC-OptLev) is constructed for the measurement of small changes in the angle of orientation of a surface. The dynamic range of SC-OptLev is found to be twice that of a conventional OptLev for the same experimental configurations. Different filtering mechanisms are implemented and the correlation results are compared. Two types of computer automated SC-OptLevs, open source based computing system with a low-cost image sensor and a commercial computing system, are presented with assistive computational modules.

[{'version': 'v1', 'created': 'Fri, 26 Apr 2019 10:35:30 GMT'}]

2019-09-04

[['Vijayakumar', 'A.', ''], ['Jayavel', 'D.', ''], ['Muthaiah', 'M.', ''], ['Bhattacharya', 'Shanti', ''], ['Rosen', 'Joseph', '']]

2107.03711

Jakub Gajarsk\'y

Jakub Gajarsk\'y, Micha{\l} Pilipczuk, Szymon Toru\'nczyk

Stable graphs of bounded twin-width

45 pages, 5 figures

cs.LO cs.DM math.CO

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

We prove that every class of graphs $\mathscr C$ that is monadically stable and has bounded twin-width can be transduced from some class with bounded sparse twin-width. This generalizes analogous results for classes of bounded linear cliquewidth and of bounded cliquewidth. It also implies that monadically stable classes of bounded twin-widthare linearly $\chi$-bounded.

[{'version': 'v1', 'created': 'Thu, 8 Jul 2021 09:42:00 GMT'}, {'version': 'v2', 'created': 'Sat, 17 Sep 2022 22:33:27 GMT'}]

2022-09-20

[['Gajarský', 'Jakub', ''], ['Pilipczuk', 'Michał', ''], ['Toruńczyk', 'Szymon', '']]

1605.07847

Roeland Juchtmans

Roeland Juchtmans, Laura Clark, Axel Lubk, Jo Verbeeck

Investigation into spiral phase plate contrast in optical and electron microscopy

7 pages, 4 figures

Phys. Rev. A 94, 023838 (2016)

10.1103/PhysRevA.94.023838

physics.optics

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The use of phase plates in the back focal plane of a microscope is a well established technique in optical microscopy to increase the contrast of weakly interacting samples and is gaining interest in electron microscopy as well. In this paper we study the spiral phase plate (SPP), also called helical, vortex, or two-dimensional Hilbert phase plate, that adds an angularly dependent phase of the form $e^{i\ell\phi}$ to the exit wave in Fourier space. In the limit of large collection angles, we analytically calculate that the average of a pair of $\ell=\pm1$ SPP images is directly proportional to the gradient squared of the exit wave, explaining the edge contrast previously seen in optical SPP work. The difference between a clockwise-anticlockwise pair of SPP images and conditions where this difference vanishes and the gradient of the exit wave can be seen from one single SPP image, are discussed. Finally, we demonstrate how with three images, one without and one with each of an $\ell=\pm1$ SPP, may give enough information to reconstruct both the amplitude and the phase of the exit wave. This work provides the theoretical background to interpret images obtained with a SPP and can help enable new experiments to study for example magnetic materials in an electron microscope.

[{'version': 'v1', 'created': 'Wed, 25 May 2016 12:17:37 GMT'}, {'version': 'v2', 'created': 'Tue, 23 Aug 2016 15:55:44 GMT'}]

2016-08-31

[['Juchtmans', 'Roeland', ''], ['Clark', 'Laura', ''], ['Lubk', 'Axel', ''], ['Verbeeck', 'Jo', '']]

1910.00977

Andriy Goychuk

Andriy Goychuk and Erwin Frey

Protein recruitment through indirect mechanochemical interactions

10.1103/PhysRevLett.123.178101

physics.bio-ph q-bio.SC

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Some of the key proteins essential for important cellular processes are capable of recruiting other proteins from the cytosol to phospholipid membranes. The physical basis for this cooperativity of binding is, surprisingly, still unclear. Here, we suggest a general feedback mechanism that explains cooperativity through mechanochemical coupling mediated by the mechanical properties of phospholipid membranes. Our theory predicts that protein recruitment, and therefore also protein pattern formation, involves membrane deformation, and is strongly affected by membrane composition.

[{'version': 'v1', 'created': 'Wed, 2 Oct 2019 14:33:04 GMT'}]

2019-10-24

[['Goychuk', 'Andriy', ''], ['Frey', 'Erwin', '']]

1504.03573

Marcus A. Brubaker

Marcus A. Brubaker, Ali Punjani and David J. Fleet

Building Proteins in a Day: Efficient 3D Molecular Reconstruction

To be presented at IEEE Conference on Computer Vision and Pattern Recognition (CVPR) 2015

10.1109/CVPR.2015.7298929

cs.CV q-bio.QM

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Discovering the 3D atomic structure of molecules such as proteins and viruses is a fundamental research problem in biology and medicine. Electron Cryomicroscopy (Cryo-EM) is a promising vision-based technique for structure estimation which attempts to reconstruct 3D structures from 2D images. This paper addresses the challenging problem of 3D reconstruction from 2D Cryo-EM images. A new framework for estimation is introduced which relies on modern stochastic optimization techniques to scale to large datasets. We also introduce a novel technique which reduces the cost of evaluating the objective function during optimization by over five orders or magnitude. The net result is an approach capable of estimating 3D molecular structure from large scale datasets in about a day on a single workstation.

[{'version': 'v1', 'created': 'Tue, 14 Apr 2015 14:56:17 GMT'}]

2016-11-18

[['Brubaker', 'Marcus A.', ''], ['Punjani', 'Ali', ''], ['Fleet', 'David J.', '']]

0805.1617

Mattias Marklund

P. K. Shukla, G. Brodin, M. Marklund, L. Stenflo

Wake field generation and nonlinear evolution in a magnetized electron-positron-ion plasma

9 pages

10.1063/1.2970098

physics.plasm-ph astro-ph

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The nonlinear propagation of a circularly polarized electromagnetic (CPEM) wave in a strongly magnetized electron-positron-ion plasma is investigated. Two coupled equations describing the interaction between a high-frequency CPEM wave and the low-frequency electrostatic wake field are derived. It is found that the generation of the wake fields depends on the presence of the ion species. The wake field generation in turn leads to de-acceleration and frequency down conversion of the electromagnetic pulse.

[{'version': 'v1', 'created': 'Mon, 12 May 2008 12:16:29 GMT'}]

2009-11-13

[['Shukla', 'P. K.', ''], ['Brodin', 'G.', ''], ['Marklund', 'M.', ''], ['Stenflo', 'L.', '']]

physics/0411131

Parameshwaran Vasu

M.B. Chowdhuri, D. Raju, R. Manchanda, Vinay Kumar, Shankar Joisa, P. K. Atrey, C.V.S. Rao, R. Jha, R. Singh, P. Vasu, the Aditya Collaboration

Exploring Core-to-edge Transport in Aditya Tokamak by Oscillations Observed in the edge Radiation

12th International Congress on Plasma Physics, 25-29 October 2004, Nice (France)

physics.plasm-ph

Understanding of the transport in a Tokamak plasma is an important issue. Various mechanisms have been reported in the literature to relate the core phenomenon to edge phenomenon. Sawtooth and Mirnov oscillations caused by MHD instabilities are generally observed in Tokamak discharges. Observation of these effects in the visible radiation from outer edge may offer a possible means to understand the transport.Oscillations in the visible radiation from outer region of the plasma have been observed during recent Aditya discharges. Percentage modulation of these oscillations vary with the Lines of Sight (LOS) of the chords and surfaces on which they terminate. This has been found in both the low frequency (~1 kHz) oscillations that seem to correlate with sawteething in SXR signals and the higher frequency (~10 kHz) oscillations that correlate well with Mirnov signals indicative of m/n=2/1 mode rotation. This suggests that the extent to which the MHD instabilities in the central region of the plasma column are reflected in the edge radiation depends on the interaction of the plasma with the surface at the extremity of the LOS. The release of particle/ energy accompanying the MHD instabilities leads to a large influx of particles from such surfaces. Cross-bispectral analysis suggests that a mode (having frequency of ~20 kHz) is also generated due to the interaction of m/n=1/1 (~10 kHz, seen in SXR) and m/n=2/1 (~10 kHz, seen in Mirnov, Visible & Microwave Interferometer signals). By possible selection rules, this mode seems to be a m/n=3/2 mode. This mode is seen in Mirnov, Visible & Interferometer signals. Behaviour of these oscillations on various LOS and their relation to SXR&Mirnov signals can lead to an understanding of the transport phenomenon. These observations and our interpretations will be presented.

[{'version': 'v1', 'created': 'Mon, 15 Nov 2004 09:28:04 GMT'}]

2007-05-23

[['Chowdhuri', 'M. B.', ''], ['Raju', 'D.', ''], ['Manchanda', 'R.', ''], ['Kumar', 'Vinay', ''], ['Joisa', 'Shankar', ''], ['Atrey', 'P. K.', ''], ['Rao', 'C. V. S.', ''], ['Jha', 'R.', ''], ['Singh', 'R.', ''], ['Vasu', 'P.', ''], ['Collaboration', 'the Aditya', '']]

2301.05453

Ana-Maria Bucur

Ana-Maria Bucur, Adrian Cosma, Paolo Rosso, Liviu P. Dinu

It's Just a Matter of Time: Detecting Depression with Time-Enriched Multimodal Transformers

Accepted at ECIR 2023

cs.CL

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Depression detection from user-generated content on the internet has been a long-lasting topic of interest in the research community, providing valuable screening tools for psychologists. The ubiquitous use of social media platforms lays out the perfect avenue for exploring mental health manifestations in posts and interactions with other users. Current methods for depression detection from social media mainly focus on text processing, and only a few also utilize images posted by users. In this work, we propose a flexible time-enriched multimodal transformer architecture for detecting depression from social media posts, using pretrained models for extracting image and text embeddings. Our model operates directly at the user-level, and we enrich it with the relative time between posts by using time2vec positional embeddings. Moreover, we propose another model variant, which can operate on randomly sampled and unordered sets of posts to be more robust to dataset noise. We show that our method, using EmoBERTa and CLIP embeddings, surpasses other methods on two multimodal datasets, obtaining state-of-the-art results of 0.931 F1 score on a popular multimodal Twitter dataset, and 0.902 F1 score on the only multimodal Reddit dataset.

[{'version': 'v1', 'created': 'Fri, 13 Jan 2023 09:40:19 GMT'}, {'version': 'v2', 'created': 'Mon, 6 Feb 2023 14:42:24 GMT'}]

2023-02-07

[['Bucur', 'Ana-Maria', ''], ['Cosma', 'Adrian', ''], ['Rosso', 'Paolo', ''], ['Dinu', 'Liviu P.', '']]

2105.02061

Mengyang Sun

Wei Suo, Mengyang Sun, Peng Wang, Qi Wu

Proposal-free One-stage Referring Expression via Grid-Word Cross-Attention

To be published in the 30th International Joint Conference on Artificial Intelligence (IJCAI-2021)

cs.CV

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Referring Expression Comprehension (REC) has become one of the most important tasks in visual reasoning, since it is an essential step for many vision-and-language tasks such as visual question answering. However, it has not been widely used in many downstream tasks because it suffers 1) two-stage methods exist heavy computation cost and inevitable error accumulation, and 2) one-stage methods have to depend on lots of hyper-parameters (such as anchors) to generate bounding box. In this paper, we present a proposal-free one-stage (PFOS) model that is able to regress the region-of-interest from the image, based on a textual query, in an end-to-end manner. Instead of using the dominant anchor proposal fashion, we directly take the dense-grid of an image as input for a cross-attention transformer that learns grid-word correspondences. The final bounding box is predicted directly from the image without the time-consuming anchor selection process that previous methods suffer. Our model achieves the state-of-the-art performance on four referring expression datasets with higher efficiency, comparing to previous best one-stage and two-stage methods.

[{'version': 'v1', 'created': 'Wed, 5 May 2021 13:53:53 GMT'}]

2021-05-06

[['Suo', 'Wei', ''], ['Sun', 'Mengyang', ''], ['Wang', 'Peng', ''], ['Wu', 'Qi', '']]

1312.2801

Matthias Egg

Matthias Egg and Michael Esfeld

Non-local common cause explanations for EPR

quant-ph physics.hist-ph

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The paper argues that a causal explanation of the correlated outcomes of EPR-type experiments is desirable and possible. It shows how Bohmian mechanics and the GRW mass density theory offer such an explanation in terms of a non-local common cause.

[{'version': 'v1', 'created': 'Tue, 10 Dec 2013 14:02:14 GMT'}]

2013-12-11

[['Egg', 'Matthias', ''], ['Esfeld', 'Michael', '']]

2212.07805

Alberto Ravagnani

Anina Gruica, Benjamin Jany, Alberto Ravagnani

Duality and LP Bounds for Codes with Locality

cs.IT math.IT math.OC

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

We initiate the study of the duality theory of locally recoverable codes, with a focus on the applications. We characterize the locality of a code in terms of the dual code, and introduce a class of invariants that refine the classical weight distribution. In this context, we establish a duality theorem analogous to (but very different from) a MacWilliams identity. As an application of our results, we obtain two new bounds for the parameters of a locally recoverable code, including an LP bound that improves on the best available bounds in several instances.

[{'version': 'v1', 'created': 'Thu, 15 Dec 2022 13:18:30 GMT'}]

2022-12-16

[['Gruica', 'Anina', ''], ['Jany', 'Benjamin', ''], ['Ravagnani', 'Alberto', '']]

2007.00254

Arabin Kumar Dey

Shankhyajyoti De, Arabin Kumar Dey, and Deepak Gauda

Construction of confidence interval for a univariate stock price signal predicted through Long Short Term Memory Network

14 pages, 11 figures

stat.ML cs.LG q-fin.ST

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

In this paper, we show an innovative way to construct bootstrap confidence interval of a signal estimated based on a univariate LSTM model. We take three different types of bootstrap methods for dependent set up. We prescribe some useful suggestions to select the optimal block length while performing the bootstrapping of the sample. We also propose a benchmark to compare the confidence interval measured through different bootstrap strategies. We illustrate the experimental results through some stock price data set.

[{'version': 'v1', 'created': 'Wed, 1 Jul 2020 05:28:20 GMT'}]

2020-07-02

[['De', 'Shankhyajyoti', ''], ['Dey', 'Arabin Kumar', ''], ['Gauda', 'Deepak', '']]

1312.2636

Boris Korzh MSci ARCS

Boris Korzh and Nino Walenta and Tommaso Lunghi and Nicolas Gisin and Hugo Zbinden

Free-running InGaAs single photon detector with 1 dark count per second at 10% efficiency

4 pages, 4 figures

Appl. Phys. Lett. 104, 081108 (2014)

10.1063/1.4866582

quant-ph physics.ins-det physics.optics

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

We present a free-running single photon detector for telecom wavelengths based on a negative feedback avalanche photodiode (NFAD). A dark count rate as low as 1 cps was obtained at a detection efficiency of 10%, with an afterpulse probability of 2.2% for 20 {\mu}s of deadtime. This was achieved by using an active hold-off circuit and cooling the NFAD with a free-piston stirling cooler down to temperatures of -110${^o}$C. We integrated two detectors into a practical, 625 MHz clocked quantum key distribution system. Stable, real-time key distribution in presence of 30 dB channel loss was possible, yielding a secret key rate of 350 bps.

[{'version': 'v1', 'created': 'Tue, 10 Dec 2013 01:00:08 GMT'}, {'version': 'v2', 'created': 'Wed, 3 Dec 2014 09:08:40 GMT'}]

2014-12-04

[['Korzh', 'Boris', ''], ['Walenta', 'Nino', ''], ['Lunghi', 'Tommaso', ''], ['Gisin', 'Nicolas', ''], ['Zbinden', 'Hugo', '']]

1612.02503

Mahmoud Abo Khamis

Mahmoud Abo Khamis, Hung Q. Ngo, Dan Suciu

What do Shannon-type Inequalities, Submodular Width, and Disjunctive Datalog have to do with one another?

cs.DB cs.DS cs.IT math.IT

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Recent works on bounding the output size of a conjunctive query with functional dependencies and degree constraints have shown a deep connection between fundamental questions in information theory and database theory. We prove analogous output bounds for disjunctive datalog rules, and answer several open questions regarding the tightness and looseness of these bounds along the way. Our bounds are intimately related to Shannon-type information inequalities. We devise the notion of a "proof sequence" of a specific class of Shannon-type information inequalities called "Shannon flow inequalities". We then show how such a proof sequence can be interpreted as symbolic instructions guiding an algorithm called "PANDA", which answers disjunctive datalog rules within the time that the size bound predicted. We show that PANDA can be used as a black-box to devise algorithms matching precisely the fractional hypertree width and the submodular width runtimes for aggregate and conjunctive queries with functional dependencies and degree constraints. Our results improve upon known results in three ways. First, our bounds and algorithms are for the much more general class of disjunctive datalog rules, of which conjunctive queries are a special case. Second, the runtime of PANDA matches precisely the submodular width bound, while the previous algorithm by Marx has a runtime that is polynomial in this bound. Third, our bounds and algorithms work for queries with input cardinality bounds, functional dependencies, and degree constraints. Overall, our results show a deep connection between three seemingly unrelated lines of research; and, our results on proof sequences for Shannon flow inequalities might be of independent interest.

[{'version': 'v1', 'created': 'Thu, 8 Dec 2016 01:06:40 GMT'}, {'version': 'v2', 'created': 'Sun, 18 Dec 2016 08:10:36 GMT'}, {'version': 'v3', 'created': 'Sat, 25 Mar 2017 23:18:03 GMT'}, {'version': 'v4', 'created': 'Wed, 1 Nov 2017 07:13:09 GMT'}]

2017-11-02

[['Khamis', 'Mahmoud Abo', ''], ['Ngo', 'Hung Q.', ''], ['Suciu', 'Dan', '']]

2002.01600

Johannes Hendriks

Johannes Hendriks, Carl Jidling, Adrian Wills and Thomas Sch\"on

Linearly Constrained Neural Networks

stat.ML cs.LG physics.comp-ph

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

We present a novel approach to modelling and learning vector fields from physical systems using neural networks that explicitly satisfy known linear operator constraints. To achieve this, the target function is modelled as a linear transformation of an underlying potential field, which is in turn modelled by a neural network. This transformation is chosen such that any prediction of the target function is guaranteed to satisfy the constraints. The approach is demonstrated on both simulated and real data examples.

[{'version': 'v1', 'created': 'Wed, 5 Feb 2020 01:27:29 GMT'}, {'version': 'v2', 'created': 'Tue, 7 Jul 2020 23:38:01 GMT'}, {'version': 'v3', 'created': 'Mon, 12 Apr 2021 01:24:06 GMT'}, {'version': 'v4', 'created': 'Wed, 28 Apr 2021 01:43:49 GMT'}]

2021-04-29

[['Hendriks', 'Johannes', ''], ['Jidling', 'Carl', ''], ['Wills', 'Adrian', ''], ['Schön', 'Thomas', '']]

1803.01234

Bryan Wong

Niranjan V. Ilawe, M. Bel\'en Oviedo, and Bryan M. Wong

Real-Time Quantum Dynamics of Long-Range Electronic Excitation Transfer in Plasmonic Nanoantennas

Accepted by the Journal of Chemical Theory and Computation

Journal of Chemical Theory and Computation, 13, 3442 (2017)

10.1021/acs.jctc.7b00423

cond-mat.mes-hall cond-mat.mtrl-sci physics.chem-ph

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Using large-scale, real-time quantum dynamics calculations, we present a detailed analysis of electronic excitation transfer (EET) mechanisms in a multi-particle plasmonic nanoantenna system. Specifically, we utilize real-time, time-dependent, density functional tight binding (RT-TDDFTB) to provide a quantum-mechanical description (at an electronic/atomistic level of detail) for characterizing and analyzing these systems, without recourse to classical approximations. We also demonstrate highly long-range electronic couplings in these complex systems and find that the range of these couplings is more than twice the conventional cutoff limit considered by FRET based approaches. Furthermore, we attribute these unusually long-ranged electronic couplings to the coherent oscillations of conduction electrons in plasmonic nanoparticles. This long-range nature of plasmonic interactions has important ramifications for EET - in particular, we show that the commonly used "nearest-neighbor" FRET model is inadequate for accurately characterizing EET even in simple plasmonic antenna systems. These findings provide a real-time, quantum-mechanical perspective for understanding EET mechanisms and provide guidance in enhancing plasmonic properties in artificial light-harvesting systems.

[{'version': 'v1', 'created': 'Sat, 3 Mar 2018 20:43:51 GMT'}]

2018-03-06

[['Ilawe', 'Niranjan V.', ''], ['Oviedo', 'M. Belén', ''], ['Wong', 'Bryan M.', '']]

2003.13728

Roberto Dale

Jos\'e M. Amig\'o and Roberto Dale and Piergiulio Tempesta

A generalized permutation entropy for random processes

9 pages, 5 figures

Chaos 31, 013115 (2021)

10.1063/5.0023419

physics.data-an

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Permutation entropy measures the complexity of deterministic time series via a data symbolic quantization consisting of rank vectors called ordinal patterns or just permutations. The reasons for the increasing popularity of this entropy in time series analysis include that (i) it converges to the Kolmogorov-Sinai entropy of the underlying dynamics in the limit of ever longer permutations, and (ii) its computation dispenses with generating and ad hoc partitions. However, permutation entropy diverges when the number of allowed permutations grows super-exponentially with their length, as is usually the case when time series are output by random processes. In this Letter we propose a generalized permutation entropy that is finite for random processes, including discrete-time dynamical systems with observational or dynamical noise.

[{'version': 'v1', 'created': 'Mon, 30 Mar 2020 18:21:53 GMT'}]

2021-03-08

[['Amigó', 'José M.', ''], ['Dale', 'Roberto', ''], ['Tempesta', 'Piergiulio', '']]

1911.03787

Yue Cao

Yue Cao, Tianlong Chen, Zhangyang Wang, Yang Shen

Learning to Optimize in Swarms

Accepted to Neural Information Processing Systems (NeurIPS2019)

cs.LG q-bio.BM stat.ML

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Learning to optimize has emerged as a powerful framework for various optimization and machine learning tasks. Current such "meta-optimizers" often learn in the space of continuous optimization algorithms that are point-based and uncertainty-unaware. To overcome the limitations, we propose a meta-optimizer that learns in the algorithmic space of both point-based and population-based optimization algorithms. The meta-optimizer targets at a meta-loss function consisting of both cumulative regret and entropy. Specifically, we learn and interpret the update formula through a population of LSTMs embedded with sample- and feature-level attentions. Meanwhile, we estimate the posterior directly over the global optimum and use an uncertainty measure to help guide the learning process. Empirical results over non-convex test functions and the protein-docking application demonstrate that this new meta-optimizer outperforms existing competitors.

[{'version': 'v1', 'created': 'Sat, 9 Nov 2019 22:25:05 GMT'}, {'version': 'v2', 'created': 'Sat, 16 Nov 2019 19:16:42 GMT'}]

2019-11-19

[['Cao', 'Yue', ''], ['Chen', 'Tianlong', ''], ['Wang', 'Zhangyang', ''], ['Shen', 'Yang', '']]

2111.14232

Charlotte Caucheteux

Charlotte Caucheteux, Alexandre Gramfort, Jean-Remi King

Long-range and hierarchical language predictions in brains and algorithms

q-bio.NC cs.AI cs.CL cs.LG cs.NE

http://creativecommons.org/licenses/by/4.0/

Deep learning has recently made remarkable progress in natural language processing. Yet, the resulting algorithms remain far from competing with the language abilities of the human brain. Predictive coding theory offers a potential explanation to this discrepancy: while deep language algorithms are optimized to predict adjacent words, the human brain would be tuned to make long-range and hierarchical predictions. To test this hypothesis, we analyze the fMRI brain signals of 304 subjects each listening to 70min of short stories. After confirming that the activations of deep language algorithms linearly map onto those of the brain, we show that enhancing these models with long-range forecast representations improves their brain-mapping. The results further reveal a hierarchy of predictions in the brain, whereby the fronto-parietal cortices forecast more abstract and more distant representations than the temporal cortices. Overall, this study strengthens predictive coding theory and suggests a critical role of long-range and hierarchical predictions in natural language processing.

[{'version': 'v1', 'created': 'Sun, 28 Nov 2021 20:26:07 GMT'}]

2021-11-30

[['Caucheteux', 'Charlotte', ''], ['Gramfort', 'Alexandre', ''], ['King', 'Jean-Remi', '']]

nlin/0510063

Nicolas Leprovost

Nicolas Leprovost (LPS), S\'ebatien Aumaitre (LPS), Kirone Mallick (SPhT)

Stability of a nonlinear oscillator with random damping

European Physical Journal B 49 (2006) 453

10.1140/epjb/e2006-00089-9

nlin.CD cond-mat.stat-mech physics.flu-dyn

A noisy damping parameter in the equation of motion of a nonlinear oscillator renders the fixed point of the system unstable when the amplitude of the noise is sufficiently large. However, the stability diagram of the system can not be predicted from the analysis of the moments of the linearized equation. In the case of a white noise, an exact formula for the Lyapunov exponent of the system is derived. We then calculate the critical damping for which the {\em nonlinear} system becomes unstable. We also characterize the intermittent structure of the bifurcated state above threshold and address the effect of temporal correlations of the noise by considering an Ornstein-Uhlenbeck noise.

[{'version': 'v1', 'created': 'Mon, 24 Oct 2005 19:43:52 GMT'}]

2016-08-16

[['Leprovost', 'Nicolas', '', 'LPS'], ['Aumaitre', 'Sébatien', '', 'LPS'], ['Mallick', 'Kirone', '', 'SPhT']]

2103.10457

Matthew Weiss

Matthew Weiss, Ming Fang, Yoann Altmann, Marc G. Paff, Angela Di Fulvio

Effect of natural gamma background radiation on portal monitor radioisotope unmixing

10.1016/j.nima.2021.165269

physics.ins-det

http://creativecommons.org/licenses/by-nc-sa/4.0/

National security relies on several layers of protection. One of the most important is the traffic control at borders and ports that exploits Radiation Portal Monitors (RPMs) to detect and deter potential smuggling attempts. Most portal monitors rely on plastic scintillators to detect gamma rays. Despite their poor energy resolution, their cost effectiveness and the possibility of growing them in large sizes makes them the gamma-ray detector of choice in RPMs. Unmixing algorithms applied to organic scintillator spectra can be used to reliably identify the bare and unshielded radionuclides that triggered an alarm, even with fewer than 1,000 detected counts and in the presence of two or three nuclides at the same time. In this work, we experimentally studied the robustness of a state-of-the-art unmixing algorithm to different radiation background spectra, due to varying atmospheric conditions, in the 16 $^\circ$C to 28 $^\circ$C temperature range. In the presence of background, the algorithm is able to identify the nuclides present in unknown radionuclide mixtures of three nuclides, when at least 1,000 counts from the sources are detected. With fewer counts available, we found larger differences of approximately 35.9$\%$ between estimated nuclide fractions and actual ones. In these low count rate regimes, the uncertainty associated by our algorithm with the identified fractions could be an additional valuable tool to determine whether the identification is reliable or a longer measurement to increase the signal-to-noise ratio is needed. Moreover, the algorithm identification performances are consistent throughout different data sets, with negligible differences in the presence of background types of different intensity and spectral shape.

[{'version': 'v1', 'created': 'Thu, 18 Mar 2021 18:15:48 GMT'}]

2021-04-28

[['Weiss', 'Matthew', ''], ['Fang', 'Ming', ''], ['Altmann', 'Yoann', ''], ['Paff', 'Marc G.', ''], ['Di Fulvio', 'Angela', '']]

1706.02240

Martin Schrimpf

Hanlin Tang, Martin Schrimpf, Bill Lotter, Charlotte Moerman, Ana Paredes, Josue Ortega Caro, Walter Hardesty, David Cox, Gabriel Kreiman

Recurrent computations for visual pattern completion

10.1073/pnas.1719397115

q-bio.NC cs.AI cs.CV cs.LG

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Making inferences from partial information constitutes a critical aspect of cognition. During visual perception, pattern completion enables recognition of poorly visible or occluded objects. We combined psychophysics, physiology and computational models to test the hypothesis that pattern completion is implemented by recurrent computations and present three pieces of evidence that are consistent with this hypothesis. First, subjects robustly recognized objects even when rendered <15% visible, but recognition was largely impaired when processing was interrupted by backward masking. Second, invasive physiological responses along the human ventral cortex exhibited visually selective responses to partially visible objects that were delayed compared to whole objects, suggesting the need for additional computations. These physiological delays were correlated with the effects of backward masking. Third, state-of-the-art feed-forward computational architectures were not robust to partial visibility. However, recognition performance was recovered when the model was augmented with attractor-based recurrent connectivity. These results provide a strong argument of plausibility for the role of recurrent computations in making visual inferences from partial information.

[{'version': 'v1', 'created': 'Wed, 7 Jun 2017 16:23:28 GMT'}, {'version': 'v2', 'created': 'Fri, 6 Apr 2018 12:29:22 GMT'}]

2018-08-15

[['Tang', 'Hanlin', ''], ['Schrimpf', 'Martin', ''], ['Lotter', 'Bill', ''], ['Moerman', 'Charlotte', ''], ['Paredes', 'Ana', ''], ['Caro', 'Josue Ortega', ''], ['Hardesty', 'Walter', ''], ['Cox', 'David', ''], ['Kreiman', 'Gabriel', '']]

2005.02061

Roman Walch

Alexandros Bampoulidis and Alessandro Bruni and Lukas Helminger and Daniel Kales and Christian Rechberger and Roman Walch

Privately Connecting Mobility to Infectious Diseases via Applied Cryptography

Accepted at PoPETs 2022

cs.CR

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Recent work has shown that cell phone mobility data has the unique potential to create accurate models for human mobility and consequently the spread of infected diseases. While prior studies have exclusively relied on a mobile network operator's subscribers' aggregated data in modelling disease dynamics, it may be preferable to contemplate aggregated mobility data of infected individuals only. Clearly, naively linking mobile phone data with health records would violate privacy by either allowing to track mobility patterns of infected individuals, leak information on who is infected, or both. This work aims to develop a solution that reports the aggregated mobile phone location data of infected individuals while still maintaining compliance with privacy expectations. To achieve privacy, we use homomorphic encryption, validation techniques derived from zero-knowledge proofs, and differential privacy. Our protocol's open-source implementation can process eight million subscribers in 70 minutes.

[{'version': 'v1', 'created': 'Tue, 5 May 2020 10:59:30 GMT'}, {'version': 'v2', 'created': 'Tue, 20 Oct 2020 14:31:57 GMT'}, {'version': 'v3', 'created': 'Mon, 11 Jan 2021 10:27:37 GMT'}, {'version': 'v4', 'created': 'Mon, 13 Jun 2022 11:19:49 GMT'}]

2022-06-14

[['Bampoulidis', 'Alexandros', ''], ['Bruni', 'Alessandro', ''], ['Helminger', 'Lukas', ''], ['Kales', 'Daniel', ''], ['Rechberger', 'Christian', ''], ['Walch', 'Roman', '']]

1601.02852

Tae-Hyun Oh

Jinsoo Choi, Tae-Hyun Oh, In So Kweon

Human Attention Estimation for Natural Images: An Automatic Gaze Refinement Approach

cs.CV cs.HC cs.MM

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Photo collections and its applications today attempt to reflect user interactions in various forms. Moreover, photo collections aim to capture the users' intention with minimum effort through applications capturing user intentions. Human interest regions in an image carry powerful information about the user's behavior and can be used in many photo applications. Research on human visual attention has been conducted in the form of gaze tracking and computational saliency models in the computer vision community, and has shown considerable progress. This paper presents an integration between implicit gaze estimation and computational saliency model to effectively estimate human attention regions in images on the fly. Furthermore, our method estimates human attention via implicit calibration and incremental model updating without any active participation from the user. We also present extensive analysis and possible applications for personal photo collections.

[{'version': 'v1', 'created': 'Tue, 12 Jan 2016 13:31:38 GMT'}]

2016-01-13

[['Choi', 'Jinsoo', ''], ['Oh', 'Tae-Hyun', ''], ['Kweon', 'In So', '']]

2207.07797

Lei Hsiung

Lei Hsiung, Yun-Yun Tsai, Pin-Yu Chen, Tsung-Yi Ho

CARBEN: Composite Adversarial Robustness Benchmark

IJCAI 2022 Demo Track; The demonstration is at https://hsiung.cc/CARBEN/

cs.CV cs.AI cs.HC

http://creativecommons.org/licenses/by/4.0/

Prior literature on adversarial attack methods has mainly focused on attacking with and defending against a single threat model, e.g., perturbations bounded in Lp ball. However, multiple threat models can be combined into composite perturbations. One such approach, composite adversarial attack (CAA), not only expands the perturbable space of the image, but also may be overlooked by current modes of robustness evaluation. This paper demonstrates how CAA's attack order affects the resulting image, and provides real-time inferences of different models, which will facilitate users' configuration of the parameters of the attack level and their rapid evaluation of model prediction. A leaderboard to benchmark adversarial robustness against CAA is also introduced.

[{'version': 'v1', 'created': 'Sat, 16 Jul 2022 01:08:44 GMT'}]

2022-07-19

[['Hsiung', 'Lei', ''], ['Tsai', 'Yun-Yun', ''], ['Chen', 'Pin-Yu', ''], ['Ho', 'Tsung-Yi', '']]

1712.01825

Johann (Jan) Rafelski

Johann Rafelski, Martin Formanek, and Andrew Steinmetz

Relativistic Dynamics of Point Magnetic Moment

11 pages

Eur. Phys. J. C (2018) 78: 6

10.1140/epjc/s10052-017-5493-2

physics.class-ph hep-ph physics.acc-ph physics.plasm-ph

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The covariant motion of a classical point particle with magnetic moment in the presence of (external) electromagnetic fields is revisited. We are interested in understanding Lorentz force extension involving point particle magnetic moment (Stern-Gerlach force) and how the spin precession dynamics is modified for consistency. We introduce spin as a classical particle property inherent to Poincare\'e symmetry of space-time. We propose a covariant formulation of the magnetic force based on a \lq magnetic\rq\ 4-potential and show how the point particle magnetic moment relates to the Amperian (current loop) and Gilbertian (magnetic monopole) description. We show that covariant spin precession lacks a unique form and discuss connection to $g-2$ anomaly. We consider variational action principle and find that a consistent extension of Lorentz force to include magnetic spin force is not straightforward. We look at non-covariant particle dynamics, and present a short introduction to dynamics of (neutral) particles hit by a laser pulse of arbitrary shape.

[{'version': 'v1', 'created': 'Fri, 1 Dec 2017 20:05:19 GMT'}]

2018-01-17

[['Rafelski', 'Johann', ''], ['Formanek', 'Martin', ''], ['Steinmetz', 'Andrew', '']]

1801.02376

Tao Guo

Tao Guo and Raymond W. Yeung

The Explicit Coding Rate Region of Symmetric Multilevel Diversity Coding

cs.IT math.IT

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

It is well known that {\em superposition coding}, namely separately encoding the independent sources, is optimal for symmetric multilevel diversity coding (SMDC) (Yeung-Zhang 1999). However, the characterization of the coding rate region therein involves uncountably many linear inequalities and the constant term (i.e., the lower bound) in each inequality is given in terms of the solution of a linear optimization problem. Thus this implicit characterization of the coding rate region does not enable the determination of the achievability of a given rate tuple. In this paper, we first obtain closed-form expressions of these uncountably many inequalities. Then we identify a finite subset of inequalities that is sufficient for characterizing the coding rate region. This gives an explicit characterization of the coding rate region. We further show by the symmetry of the problem that only a much smaller subset of this finite set of inequalities needs to be verified in determining the achievability of a given rate tuple. Yet, the cardinality of this smaller set grows at least exponentially fast with $L$. We also present a subset entropy inequality, which together with our explicit characterization of the coding rate region, is sufficient for proving the optimality of superposition coding.

[{'version': 'v1', 'created': 'Mon, 8 Jan 2018 10:50:38 GMT'}, {'version': 'v2', 'created': 'Tue, 21 May 2019 14:34:09 GMT'}]

2019-05-22

[['Guo', 'Tao', ''], ['Yeung', 'Raymond W.', '']]

2203.05226

Xavier Letartre

X. Letartre, S. Mazauric, S. Cueff, T. Benyattou, H S. Nguyen and P. Viktorovitch

Analytical non-Hermitian description of Photonic Crystals with arbitrary Lateral and Transverse symmetry

34 pages, 23 figures

10.1103/PhysRevA.106.033510

physics.optics

http://creativecommons.org/publicdomain/zero/1.0/

In this work we propose a general theoretical approach to the modelling of complex dispersion characteristics of leaky optical modes operating in photonic crystal slab composed of two high-index contrast gratings, beyond the protection of the light cone. Opening access of wave-guided resonances to free space continuum provides large amount of extra degrees of freedom for mode coupling engineering. Not only can the two gratings communicate via near field coupling, but they are also allowed to couple via the propagating radiated field. Our analytical model, based on a non-Hermitian Hamiltonian, including both coupling schemes, allows for a unified description of the wide family of optical modes which may be generated within uni-dimensional photonic crystal. Through a variety of illustrative examples, we show that our theoretical approach provide a simplified categorization of these modes, but it is also a powerful enabler for the discovery of novel photonic species. Finally, as proof-of-concept, we demonstrate experimentally the formation of a Dirac point at the merging of three bound states in the continuum that is the most achieved photonic specie discussed in this work.

[{'version': 'v1', 'created': 'Thu, 10 Mar 2022 08:19:08 GMT'}, {'version': 'v2', 'created': 'Fri, 25 Mar 2022 20:12:24 GMT'}, {'version': 'v3', 'created': 'Tue, 6 Sep 2022 07:47:46 GMT'}]

2022-10-05

[['Letartre', 'X.', ''], ['Mazauric', 'S.', ''], ['Cueff', 'S.', ''], ['Benyattou', 'T.', ''], ['Nguyen', 'H S.', ''], ['Viktorovitch', 'P.', '']]

0712.3757

Alexander Kholosha

Tor Helleseth and Alexander Kholosha and Aina Johanssen

$m$-Sequences of Different Lengths with Four-Valued Cross Correlation

26 pages

cs.DM cs.CR

{\bf Abstract.} Considered is the distribution of the cross correlation between $m$-sequences of length $2^m-1$, where $m$ is even, and $m$-sequences of shorter length $2^{m/2}-1$. The infinite family of pairs of $m$-sequences with four-valued cross correlation is constructed and the complete correlation distribution of this family is determined.

[{'version': 'v1', 'created': 'Fri, 21 Dec 2007 17:31:27 GMT'}]

2007-12-24

[['Helleseth', 'Tor', ''], ['Kholosha', 'Alexander', ''], ['Johanssen', 'Aina', '']]

2006.09252

Giorgos Bouritsas

Giorgos Bouritsas, Fabrizio Frasca, Stefanos Zafeiriou, Michael M. Bronstein

Improving Graph Neural Network Expressivity via Subgraph Isomorphism Counting

cs.LG cs.SI stat.ML

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

While Graph Neural Networks (GNNs) have achieved remarkable results in a variety of applications, recent studies exposed important shortcomings in their ability to capture the structure of the underlying graph. It has been shown that the expressive power of standard GNNs is bounded by the Weisfeiler-Leman (WL) graph isomorphism test, from which they inherit proven limitations such as the inability to detect and count graph substructures. On the other hand, there is significant empirical evidence, e.g. in network science and bioinformatics, that substructures are often intimately related to downstream tasks. To this end, we propose "Graph Substructure Networks" (GSN), a topologically-aware message passing scheme based on substructure encoding. We theoretically analyse the expressive power of our architecture, showing that it is strictly more expressive than the WL test, and provide sufficient conditions for universality. Importantly, we do not attempt to adhere to the WL hierarchy; this allows us to retain multiple attractive properties of standard GNNs such as locality and linear network complexity, while being able to disambiguate even hard instances of graph isomorphism. We perform an extensive experimental evaluation on graph classification and regression tasks and obtain state-of-the-art results in diverse real-world settings including molecular graphs and social networks. The code is publicly available at https://github.com/gbouritsas/graph-substructure-networks.

[{'version': 'v1', 'created': 'Tue, 16 Jun 2020 15:30:31 GMT'}, {'version': 'v2', 'created': 'Tue, 5 Jan 2021 15:03:04 GMT'}, {'version': 'v3', 'created': 'Mon, 5 Jul 2021 13:22:05 GMT'}]

2021-07-06

[['Bouritsas', 'Giorgos', ''], ['Frasca', 'Fabrizio', ''], ['Zafeiriou', 'Stefanos', ''], ['Bronstein', 'Michael M.', '']]

1712.02690

Ori Peled

Ori Peled, Oron Sabag and Haim H. Permuter

Feedback Capacity and Coding for the $(0,k)$-RLL Input-Constrained BEC

37 pages, 14 figures

cs.IT math.IT

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The input-constrained binary erasure channel (BEC) with strictly causal feedback is studied. The channel input sequence must satisfy the $(0,k)$-runlength limited (RLL) constraint, i.e., no more than $k$ consecutive `$0$'s are allowed. The feedback capacity of this channel is derived for all $k\geq 1$, and is given by $$C^\mathrm{fb}_{(0,k)}(\varepsilon) = \max\frac{\overline{\varepsilon}H_2(\delta_0)+\sum_{i=1}^{k-1}\left(\overline{\varepsilon}^{i+1}H_2(\delta_i)\prod_{m=0}^{i-1}\delta_m\right)}{1+\sum_{i=0}^{k-1}\left(\overline{\varepsilon}^{i+1} \prod_{m=0}^{i}\delta_m\right)},$$ where $\varepsilon$ is the erasure probability, $\overline{\varepsilon}=1-\varepsilon$ and $H_2(\cdot)$ is the binary entropy function. The maximization is only over $\delta_{k-1}$, while the parameters $\delta_i$ for $i\leq k-2$ are straightforward functions of $\delta_{k-1}$. The lower bound is obtained by constructing a simple coding for all $k\geq1$. It is shown that the feedback capacity can be achieved using zero-error, variable length coding. For the converse, an upper bound on the non-causal setting, where the erasure is available to the encoder just prior to the transmission, is derived. This upper bound coincides with the lower bound and concludes the search for both the feedback capacity and the non-causal capacity. As a result, non-causal knowledge of the erasures at the encoder does not increase the feedback capacity for the $(0,k)$-RLL input-constrained BEC. This property does not hold in general: the $(2,\infty)$-RLL input-constrained BEC, where every `$1$' is followed by at least two `$0$'s, is used to show that the feedback capacity can be strictly greater than the non-causal capacity.

[{'version': 'v1', 'created': 'Thu, 7 Dec 2017 16:11:06 GMT'}]

2017-12-08

[['Peled', 'Ori', ''], ['Sabag', 'Oron', ''], ['Permuter', 'Haim H.', '']]

2301.01231

Mona Bavarian

Tung Nguyen and Mona Bavarian

Machine Learning Approach to Polymerization Reaction Engineering: Determining Monomers Reactivity Ratios

4 figures in paper, 4 figures in supplementary

cs.LG cond-mat.soft q-bio.BM

http://creativecommons.org/licenses/by-nc-nd/4.0/

Here, we demonstrate how machine learning enables the prediction of comonomers reactivity ratios based on the molecular structure of monomers. We combined multi-task learning, multi-inputs, and Graph Attention Network to build a model capable of predicting reactivity ratios based on the monomers chemical structures.

[{'version': 'v1', 'created': 'Tue, 3 Jan 2023 17:23:26 GMT'}]

2023-01-04

[['Nguyen', 'Tung', ''], ['Bavarian', 'Mona', '']]

1605.01224

Karel Lenc

Karel Lenc and Andrea Vedaldi

Learning Covariant Feature Detectors

cs.CV

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Local covariant feature detection, namely the problem of extracting viewpoint invariant features from images, has so far largely resisted the application of machine learning techniques. In this paper, we propose the first fully general formulation for learning local covariant feature detectors. We propose to cast detection as a regression problem, enabling the use of powerful regressors such as deep neural networks. We then derive a covariance constraint that can be used to automatically learn which visual structures provide stable anchors for local feature detection. We support these ideas theoretically, proposing a novel analysis of local features in term of geometric transformations, and we show that all common and many uncommon detectors can be derived in this framework. Finally, we present empirical results on translation and rotation covariant detectors on standard feature benchmarks, showing the power and flexibility of the framework.

[{'version': 'v1', 'created': 'Wed, 4 May 2016 11:11:07 GMT'}, {'version': 'v2', 'created': 'Fri, 9 Sep 2016 14:44:36 GMT'}]

2016-09-12

[['Lenc', 'Karel', ''], ['Vedaldi', 'Andrea', '']]

2103.08966

Maria Lucia Sampoli Prof.

A. Aimi, M. Diligenti, M.L. Sampoli, A. Sestini

Isogemetric Analysis and Symmetric Galerkin BEM: a 2D numerical study

Applied Mathematics and Computation, vol 272 (2016), 173-186

10.1016/j.amc.2015.08.097

math.NA cs.NA

http://creativecommons.org/licenses/by-nc-nd/4.0/

Isogeometric approach applied to Boundary Element Methods is an emerging research area. In this context, the aim of the present contribution is that of investigating, from a numerical point of view, the Symmetric Galerkin Boundary Element Method (SGBEM) devoted to the solution of 2D boundary value problems for the Laplace equation, where the boundary and the unknowns on it are both represented by B-splines. We mainly compare this approach, which we call IGA-SGBEM, with a curvilinear SGBEM, which operates on any boundary given by explicit parametric representation and where the approximate solution is obtained using Lagrangian basis. Both techniques are further compared with a standard (conventional) SGBEM approach, where the boundary of the assigned problem is approximated by linear elements and the numerical solution is expressed in terms of Lagrangian basis. Several examples will be presented and discussed, underlying benefits and drawbacks of all the above-mentioned approaches.

[{'version': 'v1', 'created': 'Tue, 16 Mar 2021 10:45:48 GMT'}]

2022-04-07

[['Aimi', 'A.', ''], ['Diligenti', 'M.', ''], ['Sampoli', 'M. L.', ''], ['Sestini', 'A.', '']]

2108.03894

Yaser Souri

Yaser Souri, Yazan Abu Farha, Fabien Despinoy, Gianpiero Francesca and Juergen Gall

FIFA: Fast Inference Approximation for Action Segmentation

cs.CV cs.LG

http://creativecommons.org/licenses/by/4.0/

We introduce FIFA, a fast approximate inference method for action segmentation and alignment. Unlike previous approaches, FIFA does not rely on expensive dynamic programming for inference. Instead, it uses an approximate differentiable energy function that can be minimized using gradient-descent. FIFA is a general approach that can replace exact inference improving its speed by more than 5 times while maintaining its performance. FIFA is an anytime inference algorithm that provides a better speed vs. accuracy trade-off compared to exact inference. We apply FIFA on top of state-of-the-art approaches for weakly supervised action segmentation and alignment as well as fully supervised action segmentation. FIFA achieves state-of-the-art results on most metrics on two action segmentation datasets.

[{'version': 'v1', 'created': 'Mon, 9 Aug 2021 09:23:43 GMT'}]

2021-08-10

[['Souri', 'Yaser', ''], ['Farha', 'Yazan Abu', ''], ['Despinoy', 'Fabien', ''], ['Francesca', 'Gianpiero', ''], ['Gall', 'Juergen', '']]

cs/9811031

Otto Schnurr

Orhan Karaali, Gerald Corrigan and Ira Gerson

Speech Synthesis with Neural Networks

6 pages, PostScript

World Congress on Neural Networks (1996) 45-50. San Diego

cs.NE cs.HC

Text-to-speech conversion has traditionally been performed either by concatenating short samples of speech or by using rule-based systems to convert a phonetic representation of speech into an acoustic representation, which is then converted into speech. This paper describes a system that uses a time-delay neural network (TDNN) to perform this phonetic-to-acoustic mapping, with another neural network to control the timing of the generated speech. The neural network system requires less memory than a concatenation system, and performed well in tests comparing it to commercial systems using other technologies.

[{'version': 'v1', 'created': 'Tue, 24 Nov 1998 23:33:12 GMT'}]

2007-05-23

[['Karaali', 'Orhan', ''], ['Corrigan', 'Gerald', ''], ['Gerson', 'Ira', '']]

2103.06112

Fernando Caballero Prof.

Fernando Caballero and Luis Merino

DLL: Direct LIDAR Localization. A map-based localization approach for aerial robots

Accepted for IROS2021. Associated code can be downloaded from https://github.com/robotics-upo/dll

cs.RO

http://creativecommons.org/licenses/by/4.0/

This paper presents DLL, a fast direct map-based localization technique using 3D LIDAR for its application to aerial robots. DLL implements a point cloud to map registration based on non-linear optimization of the distance of the points and the map, thus not requiring features, neither point correspondences. Given an initial pose, the method is able to track the pose of the robot by refining the predicted pose from odometry. Through benchmarks using real datasets and simulations, we show how the method performs much better than Monte-Carlo localization methods and achieves comparable precision to other optimization-based approaches but running one order of magnitude faster. The method is also robust under odometric errors. The approach has been implemented under the Robot Operating System (ROS), and it is publicly available.

[{'version': 'v1', 'created': 'Wed, 10 Mar 2021 15:05:03 GMT'}, {'version': 'v2', 'created': 'Tue, 27 Jul 2021 15:48:38 GMT'}]

2021-07-28

[['Caballero', 'Fernando', ''], ['Merino', 'Luis', '']]

2205.01316

Xin Lin

Xin Lin, Changxing Ding, Yibing Zhan, Zijian Li, Dacheng Tao

HL-Net: Heterophily Learning Network for Scene Graph Generation

Accepted to CVPR 2022

cs.CV

http://creativecommons.org/licenses/by-sa/4.0/

Scene graph generation (SGG) aims to detect objects and predict their pairwise relationships within an image. Current SGG methods typically utilize graph neural networks (GNNs) to acquire context information between objects/relationships. Despite their effectiveness, however, current SGG methods only assume scene graph homophily while ignoring heterophily. Accordingly, in this paper, we propose a novel Heterophily Learning Network (HL-Net) to comprehensively explore the homophily and heterophily between objects/relationships in scene graphs. More specifically, HL-Net comprises the following 1) an adaptive reweighting transformer module, which adaptively integrates the information from different layers to exploit both the heterophily and homophily in objects; 2) a relationship feature propagation module that efficiently explores the connections between relationships by considering heterophily in order to refine the relationship representation; 3) a heterophily-aware message-passing scheme to further distinguish the heterophily and homophily between objects/relationships, thereby facilitating improved message passing in graphs. We conducted extensive experiments on two public datasets: Visual Genome (VG) and Open Images (OI). The experimental results demonstrate the superiority of our proposed HL-Net over existing state-of-the-art approaches. In more detail, HL-Net outperforms the second-best competitors by 2.1$\%$ on the VG dataset for scene graph classification and 1.2$\%$ on the IO dataset for the final score. Code is available at https://github.com/siml3/HL-Net.

[{'version': 'v1', 'created': 'Tue, 3 May 2022 06:00:29 GMT'}, {'version': 'v2', 'created': 'Wed, 4 May 2022 01:04:20 GMT'}]

2022-05-05

[['Lin', 'Xin', ''], ['Ding', 'Changxing', ''], ['Zhan', 'Yibing', ''], ['Li', 'Zijian', ''], ['Tao', 'Dacheng', '']]

1801.04573

Paola Boito

Paola Boito, Yuli Eidelman, Luca Gemignani

Computing the Reciprocal of a $\phi$-function by Rational Approximation

math.NA cs.NA

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

In this paper we introduce a family of rational approximations of the reciprocal of a $\phi$-function involved in the explicit solutions of certain linear differential equations, as well as in integration schemes evolving on manifolds. The derivation and properties of this family of approximations applied to scalar and matrix arguments are presented. Moreover, we show that the matrix functions computed by these approximations exhibit decaying properties comparable to the best existing theoretical bounds. Numerical examples highlight the benefits of the proposed rational approximations w.r.t.~the classical Taylor polynomials and other rational functions.

[{'version': 'v1', 'created': 'Sun, 14 Jan 2018 15:28:49 GMT'}, {'version': 'v2', 'created': 'Wed, 12 Feb 2020 20:47:43 GMT'}, {'version': 'v3', 'created': 'Mon, 17 May 2021 12:55:25 GMT'}]

2021-05-18

[['Boito', 'Paola', ''], ['Eidelman', 'Yuli', ''], ['Gemignani', 'Luca', '']]

2110.14900

Ieng-Wai Un

Yonatan Dubi and Ieng-Wai Un and Yonatan Sivan

Distinguishing thermal from non-thermal ("hot") carries in illuminated molecular junctions

cond-mat.mes-hall physics.optics

http://creativecommons.org/licenses/by/4.0/

The search for the signature of non-thermal (so-called ``hot'') electrons in illuminated plasmonic nanostructures requires a detailed understanding of the non-equilibrium electron distribution under illumination, as well as a careful design of the experimental system employed to distinguish non-thermal electrons from thermal ones. Here, we provide a theory for using plasmonic molecular junctions to achieve this goal. We show how non-thermal electrons can be measured directly and separately from the unavoidable thermal response, and discuss the relevance of our theory to recent experiments.

[{'version': 'v1', 'created': 'Thu, 28 Oct 2021 05:56:24 GMT'}, {'version': 'v2', 'created': 'Fri, 29 Oct 2021 12:46:08 GMT'}, {'version': 'v3', 'created': 'Mon, 8 Nov 2021 07:02:56 GMT'}, {'version': 'v4', 'created': 'Sun, 13 Feb 2022 06:41:27 GMT'}]

2022-02-15

[['Dubi', 'Yonatan', ''], ['Un', 'Ieng-Wai', ''], ['Sivan', 'Yonatan', '']]

2010.03538

Esin Durmus

Jialu Li, Esin Durmus and Claire Cardie

Exploring the Role of Argument Structure in Online Debate Persuasion

Accepted to EMNLP 2020

cs.CL

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Online debate forums provide users a platform to express their opinions on controversial topics while being exposed to opinions from diverse set of viewpoints. Existing work in Natural Language Processing (NLP) has shown that linguistic features extracted from the debate text and features encoding the characteristics of the audience are both critical in persuasion studies. In this paper, we aim to further investigate the role of discourse structure of the arguments from online debates in their persuasiveness. In particular, we use the factor graph model to obtain features for the argument structure of debates from an online debating platform and incorporate these features to an LSTM-based model to predict the debater that makes the most convincing arguments. We find that incorporating argument structure features play an essential role in achieving the better predictive performance in assessing the persuasiveness of the arguments in online debates.

[{'version': 'v1', 'created': 'Wed, 7 Oct 2020 17:34:50 GMT'}]

2020-10-08

[['Li', 'Jialu', ''], ['Durmus', 'Esin', ''], ['Cardie', 'Claire', '']]

2009.04327

Iain Barclay

Iain Barclay, Maria Freytsis, Sherri Bucher, Swapna Radha, Alun Preece and Ian Taylor

Towards a Modelling Framework for Self-Sovereign Identity Systems

cs.SE cs.MA

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Self-sovereign Identity promises to give users control of their own data, and has the potential to foster advancements in terms of personal data privacy. Self-sovereign concepts can also be applied to other entities, such as datasets and devices. Systems adopting this paradigm will be decentralised, with messages passing between multiple actors, both human and representing other entities, in order to issue and request credentials necessary to meet individual and collective goals. Such systems are complex, and build upon social and technical interactions and behaviours. Modelling self-sovereign identity systems seeks to provide stakeholders and software architects with tools to enable them to communicate effectively, and lead to effective and well-regarded system designs and implementations. This paper draws upon research from Actor-based Modelling to guide a way forward in modelling self-sovereign systems, and reports early success in utilising the iStar 2.0 framework to provide a representation of a birth registration case study.

[{'version': 'v1', 'created': 'Wed, 9 Sep 2020 14:32:28 GMT'}, {'version': 'v2', 'created': 'Thu, 10 Sep 2020 09:12:29 GMT'}]

2020-09-11

[['Barclay', 'Iain', ''], ['Freytsis', 'Maria', ''], ['Bucher', 'Sherri', ''], ['Radha', 'Swapna', ''], ['Preece', 'Alun', ''], ['Taylor', 'Ian', '']]

physics/9706038

Lises Ifa

Sergiu I. Vacaru

Interactions and Strings in Higher Order Anisotropic and Inhomogeneous Superspaces and Isospaces

Summary of the monograph accepted by "Hadronic Press" (Palm Harbor, FL, USA), latex209, 450 pages

physics.gen-ph

The monograph gives a general geometric background of the theory of field interactions, strings and diffusion processes on spaces, superspaces and isospaces with higher order anisotropy and inhomogenity. Our approach proceeds by developing the concept of higher order anisotropic superspace which unify the logical and mathematical aspects of modern Kaluza-Klein theories and generalized Lagrange and Finsler geometry and leads to modelling of physical processes on higher order fiber bundles provided with nonlinear and distingushed connections and metric structures. The view adopted in the monograph is that a general field theory should incorporate all possible anisotropic and stochastic manifestations of classical and quantum interactions and, in consequence, a corresponding modification of basic principles and mathematical methods in formulation of physical theories. This book can be also considered as a pedagogical survey on the mentioned subjects.

[{'version': 'v1', 'created': 'Fri, 27 Jun 1997 10:12:29 GMT'}]

2008-02-03

[['Vacaru', 'Sergiu I.', '']]

2104.06597

Ankit Mahajan

Ankit Mahajan, Sandeep Sharma

Taming the sign problem in auxiliary field quantum Monte Carlo using accurate trial wave functions

15 page, 7 figures, 6 tables

physics.chem-ph

http://creativecommons.org/licenses/by/4.0/

We explore different ways of incorporating accurate trial wave functions into free projection auxiliary field quantum Monte Carlo (fp-AFQMC). Trial states employed include coupled cluster singles and doubles, multi-Slater, and symmetry projected mean-field wave functions. We adapt a recently proposed fast multi-Slater local energy evaluation algorithm for fp-AFQMC, making the use of long expansions from selected configuration interaction methods feasible. We demonstrate how these trial wave functions serve to mitigate the sign problem and accelerate convergence in quantum chemical problems, allowing the application of fp-AFQMC to systems of substantial sizes. Our calculations on the widely studied $\text{Cu}_2\text{O}_2^{2+}$ model system show that many previously reported isomerization energies differ substantially from the near-exact fp-AFQMC value.

[{'version': 'v1', 'created': 'Wed, 14 Apr 2021 02:52:23 GMT'}]

2021-04-15

[['Mahajan', 'Ankit', ''], ['Sharma', 'Sandeep', '']]

2212.03523

David Salinas

Tim Januschowski, Jan Gasthaus, Yuyang Wang, David Salinas, Valentin Flunkert, Michael Bohlke-Schneider, Laurent Callot

Criteria for Classifying Forecasting Methods

stat.ML cs.LG

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Classifying forecasting methods as being either of a "machine learning" or "statistical" nature has become commonplace in parts of the forecasting literature and community, as exemplified by the M4 competition and the conclusion drawn by the organizers. We argue that this distinction does not stem from fundamental differences in the methods assigned to either class. Instead, this distinction is probably of a tribal nature, which limits the insights into the appropriateness and effectiveness of different forecasting methods. We provide alternative characteristics of forecasting methods which, in our view, allow to draw meaningful conclusions. Further, we discuss areas of forecasting which could benefit most from cross-pollination between the ML and the statistics communities.

[{'version': 'v1', 'created': 'Wed, 7 Dec 2022 09:09:11 GMT'}]

2022-12-08

[['Januschowski', 'Tim', ''], ['Gasthaus', 'Jan', ''], ['Wang', 'Yuyang', ''], ['Salinas', 'David', ''], ['Flunkert', 'Valentin', ''], ['Bohlke-Schneider', 'Michael', ''], ['Callot', 'Laurent', '']]

1706.02535

Eugene D. Belokolos

Eugene D. Belokolos

Mendeleev Table: a Proof of Madelung Rule and Atomic Tietz Potential

SIGMA 13 (2017), 038, 15 pages

10.3842/SIGMA.2017.038

physics.atom-ph math-ph math.MP quant-ph

http://creativecommons.org/licenses/by-sa/4.0/

We prove that a neutral atom in mean-field approximation has ${\rm O}(4)$ symmetry and this fact explains the empirical $[n+l,n]$-rule or Madelung rule which describes effectively periods, structure and other properties of the Mendeleev table of chemical elements.

[{'version': 'v1', 'created': 'Wed, 7 Jun 2017 04:10:24 GMT'}]

2017-06-09

[['Belokolos', 'Eugene D.', '']]

1510.05963

Pramod Anantharam

Amit Sheth, Pramod Anantharam, Cory Henson

Semantic, Cognitive, and Perceptual Computing: Advances toward Computing for Human Experience

13 pages, 4 Figures, IEEE Computer

cs.AI

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The World Wide Web continues to evolve and serve as the infrastructure for carrying massive amounts of multimodal and multisensory observations. These observations capture various situations pertinent to people's needs and interests along with all their idiosyncrasies. To support human-centered computing that empower people in making better and timely decisions, we look towards computation that is inspired by human perception and cognition. Toward this goal, we discuss computing paradigms of semantic computing, cognitive computing, and an emerging aspect of computing, which we call perceptual computing. In our view, these offer a continuum to make the most out of vast, growing, and diverse data pertinent to human needs and interests. We propose details of perceptual computing characterized by interpretation and exploration operations comparable to the interleaving of bottom and top brain processing. This article consists of two parts. First we describe semantic computing, cognitive computing, and perceptual computing to lay out distinctions while acknowledging their complementary capabilities. We then provide a conceptual overview of the newest of these three paradigms--perceptual computing. For further insights, we focus on an application scenario of asthma management converting massive, heterogeneous and multimodal (big) data into actionable information or smart data.

[{'version': 'v1', 'created': 'Tue, 20 Oct 2015 16:57:49 GMT'}]

2015-10-21

[['Sheth', 'Amit', ''], ['Anantharam', 'Pramod', ''], ['Henson', 'Cory', '']]

cs/0509005

Anne-Marie Vercoustre

Alistair McLean (CSIRO Ict Center), Mingfang Wu (CSIRO Ict Center), Anne-Marie Vercoustre (CSIRO Ict Center)

Combining Structured Corporate Data and Document Content to Improve Expertise Finding

long version of the ADCS'03 paper

cs.IR

In this paper, we present an algorithm for automatically building expertise evidence for finding experts within an organization by combining structured corporate information with different content. We also describe our test data collection and our evaluation method. Evaluation of the algorithm shows that using organizational structure leads to a significant improvement in the precision of finding an expert. Furthermore we evaluate the impact of using different data sources on the quality of the results and conclude that Expert Finding is not a "one engine fits all" solution. It requires an analysis of the information space into which a solution will be placed and the appropriate selection and weighting scheme of the data sources.

[{'version': 'v1', 'created': 'Fri, 2 Sep 2005 08:24:07 GMT'}]

2007-05-23

[['McLean', 'Alistair', '', 'CSIRO Ict Center'], ['Wu', 'Mingfang', '', 'CSIRO Ict Center'], ['Vercoustre', 'Anne-Marie', '', 'CSIRO Ict Center']]

1707.02968

Chen Sun

Chen Sun and Abhinav Shrivastava and Saurabh Singh and Abhinav Gupta

Revisiting Unreasonable Effectiveness of Data in Deep Learning Era

ICCV 2017 camera ready

cs.CV cs.AI

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The success of deep learning in vision can be attributed to: (a) models with high capacity; (b) increased computational power; and (c) availability of large-scale labeled data. Since 2012, there have been significant advances in representation capabilities of the models and computational capabilities of GPUs. But the size of the biggest dataset has surprisingly remained constant. What will happen if we increase the dataset size by 10x or 100x? This paper takes a step towards clearing the clouds of mystery surrounding the relationship between `enormous data' and visual deep learning. By exploiting the JFT-300M dataset which has more than 375M noisy labels for 300M images, we investigate how the performance of current vision tasks would change if this data was used for representation learning. Our paper delivers some surprising (and some expected) findings. First, we find that the performance on vision tasks increases logarithmically based on volume of training data size. Second, we show that representation learning (or pre-training) still holds a lot of promise. One can improve performance on many vision tasks by just training a better base model. Finally, as expected, we present new state-of-the-art results for different vision tasks including image classification, object detection, semantic segmentation and human pose estimation. Our sincere hope is that this inspires vision community to not undervalue the data and develop collective efforts in building larger datasets.

[{'version': 'v1', 'created': 'Mon, 10 Jul 2017 17:54:31 GMT'}, {'version': 'v2', 'created': 'Fri, 4 Aug 2017 01:33:22 GMT'}]

2017-08-07

[['Sun', 'Chen', ''], ['Shrivastava', 'Abhinav', ''], ['Singh', 'Saurabh', ''], ['Gupta', 'Abhinav', '']]

1612.01842

Zaid Hussain

Zaid Hussain

An Improved One-to-All Broadcasting in Higher Dimensional Eisenstein-Jacobi Networks

cs.DC

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Recently, a higher dimensional Eisenstein-Jacobi networks, has been proposed in [22], which is shown that they have better average distance with more number of nodes than a single dimensional EJ networks. Some communication algorithms such as one-to-all and all-to-all communications are well known and used in interconnection networks. In one-to-all communication, a source node sends a message to every other node in the network. Whereas, in all-to-all communication, every node is considered as a source node and sends its message to every other node in the network. In this paper, an improved one-to-all communication algorithm in higher dimensional EJ networks is presented. The paper shows that the proposed algorithm achieves a lower average number of steps to receiving the broadcasted message. In addition, since the links are assumed to be half-duplex, the all-to-all broadcasting algorithm is divided into three phases. The simulation results are discussed and showed that the improved one-to-all algorithm achieves better traffic performance than the well-known one-to-all algorithm and has 2.7% less total number of senders

[{'version': 'v1', 'created': 'Tue, 6 Dec 2016 15:01:47 GMT'}, {'version': 'v2', 'created': 'Wed, 7 Dec 2016 06:10:53 GMT'}]

2016-12-08

[['Hussain', 'Zaid', '']]

1310.5588

Anatoly Serebrov

A.P.Serebrov, E.A.Kolomenskiy, A.N.Pirozhkov, I.A.Krasnoshekova, A.V.Vasiliev, A.O.Polyushkin, M.S.Lasakov, A.K.Fomin, I.V.Shoka, V.A. Solovey, O.M.Zherebtsov, P.Geltenbort, O.Zimmer, S.N.Ivanov, E.B.Alexandrov, S.P.Dmitriev, N.A.Dovator

New measurements of neutron electric dipole moment

9 pages, 5 figures

10.1134/S0021364014010111

nucl-ex physics.atom-ph physics.ins-det

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

We report a new measurement of the neutron electric dipole moment with the PNPI EDM spectrometer using the ultracold neutron source PF2 at the research reactor of the ILL. Its first results can be interpreted as a limit on the neutron EDM of $|d_{\rm n}| < 5.5 \times 10^{-26} \rm{e} \cdot \rm{cm}$ (90% confidence level).

[{'version': 'v1', 'created': 'Mon, 21 Oct 2013 15:10:28 GMT'}, {'version': 'v2', 'created': 'Mon, 16 Dec 2013 10:47:27 GMT'}]

2015-06-17

[['Serebrov', 'A. P.', ''], ['Kolomenskiy', 'E. A.', ''], ['Pirozhkov', 'A. N.', ''], ['Krasnoshekova', 'I. A.', ''], ['Vasiliev', 'A. V.', ''], ['Polyushkin', 'A. O.', ''], ['Lasakov', 'M. S.', ''], ['Fomin', 'A. K.', ''], ['Shoka', 'I. V.', ''], ['Solovey', 'V. A.', ''], ['Zherebtsov', 'O. M.', ''], ['Geltenbort', 'P.', ''], ['Zimmer', 'O.', ''], ['Ivanov', 'S. N.', ''], ['Alexandrov', 'E. B.', ''], ['Dmitriev', 'S. P.', ''], ['Dovator', 'N. A.', '']]

2208.00460

Kuniaki Nagayama

Kuniaki Nagayama

Complex Observation in Electron Microscopy VIII: Novel Hilbert Phase-plates to Maximize Phase-contrast Sensitivity

32 pages, 6 figures. Prepared for submission to JPSJ

physics.optics

http://creativecommons.org/licenses/by/4.0/

Phase-plate transmission electron microscopy has recently regressed since a report that Volta phase-plate phase-contrast is less sensitive than non-phase-plate phase contrast, which leads to conventional defocusing phase-contrast. What about Hilbert phase-plate phase-contrast? We report that the Hilbert phase-plate method can survive if two experiments using a pair of symmetric Hilbert phase-plates, of which phase is set to a value smaller than {\pi}, are combined. Three phase-contrast methods using the symmetric Hilbert phase-plates and Zernike phase-plate representing Volta phase-plate and Scherzer defocus respectively were compared in sensitivity theoretically relying on a contrast transfer theory and computationally on a simulator specifically designed for phase plate transmission electron microscopy. For the two phase-plate phase-contrasts, the phase that gives the highest sensitivity was searched for by changing the phase-plate phase. As a result, the symmetric Hilbert phase-plates phase-contrast was found to outperform Scherzer defocus phase-contrast in the phase around {\pi}/2. On the other hand, Zernike phase-plate phase-contrast was found considerably inferior to Scherzer defocus phase-contrast in the entire phase range from 0 to {\pi}. Furthermore, the novel Hilbert phase-plate method was compared with complex observation transmission electron microscopy, which also requires two experiments, and the origin of the higher sensitivity of symmetric Hilbert phase-plates phase-contrast was examined.

[{'version': 'v1', 'created': 'Sun, 31 Jul 2022 16:12:05 GMT'}]

2022-08-02

[['Nagayama', 'Kuniaki', '']]

0903.1337

Paolo Frasca

Ruggero Carli, Fabio Fagnani, Paolo Frasca, Sandro Zampieri

Efficient quantization for average consensus

Based on material from the third author's PhD thesis, and on a 2007 conference paper

math.OC cs.SY

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

This paper presents an algorithm which solves exponentially fast the average consensus problem on strongly connected network of digital links. The algorithm is based on an efficient zooming-in/zooming-out quantization scheme.

[{'version': 'v1', 'created': 'Sat, 7 Mar 2009 11:16:35 GMT'}]

2011-07-25

[['Carli', 'Ruggero', ''], ['Fagnani', 'Fabio', ''], ['Frasca', 'Paolo', ''], ['Zampieri', 'Sandro', '']]

2209.00955

Zhongkui Li

Xiaodong He and Zhongkui Li

Simultaneous Position and Orientation Planning of Nonholonomic Multi-Robot Systems: A Dynamic Vector Field Approach

12 pages, 11 figures

cs.RO cs.SY eess.SY

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

This paper considers the simultaneous position and orientation planning of nonholonomic multirobot systems. Different from common researches which only focus on final position constraints, we model the nonholonomic mobile robot as a rigid body and introduce the orientation as well as position constraints for the robot's final states. In other words, robots should not only reach the specified positions, but also point to the desired orientations simultaneously. The challenge of this problem lies in the underactuation of full-state motion planning, since three states need to be planned by mere two control inputs. To this end, we propose a dynamic vector field (DVF) based on the rigid body modeling. Specifically, the dynamics of the robot orientation are brought into the vector field, implying that the vector field is not static on the 2-D plane anymore, but a dynamic one varying with the attitude angle. Hence, each robot can move along the integral curve of the DVF to arrive at the desired position, and in the meantime, the attitude angle can converge to the specified value following the orientation dynamics. Subsequently, by designing a circular vector field under the framework of the DVF, we further study the obstacle avoidance and mutual-robot-collision avoidance in the motion planning. Finally, numerical simulation examples are provided to verify the effectiveness of the proposed methodology.

[{'version': 'v1', 'created': 'Fri, 2 Sep 2022 11:26:12 GMT'}]

2022-09-05

[['He', 'Xiaodong', ''], ['Li', 'Zhongkui', '']]

2009.03648

Maxime Caniot

Maxime Caniot, Vincent Bonnet, Maxime Busy, Thierry Labaye, Michel Besombes, Sebastien Courtois and Edouard Lagrue

Adapted Pepper

cs.RO cs.AI

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

One of the main issue in robotics is the lack of embedded computational power. Recently, state of the art algorithms providing a better understanding of the surroundings (Object detection, skeleton tracking, etc.) are requiring more and more computational power. The lack of embedded computational power is more significant in mass-produced robots because of the difficulties to follow the increasing computational requirements of state of the art algorithms. The integration of an additional GPU allows to overcome this lack of embedded computational power. We introduce in this paper a prototype of Pepper with an embedded GPU, but also with an additional 3D camera on the head of the robot and plugged to the late GPU. This prototype, called Adapted Pepper, was built for the European project called MuMMER (MultiModal Mall Entertainment Robot) in order to embed algorithms like OpenPose, YOLO or to process sensors information and, in all cases, avoid network dependency for deported computation.

[{'version': 'v1', 'created': 'Tue, 8 Sep 2020 11:36:37 GMT'}]

2020-09-09

[['Caniot', 'Maxime', ''], ['Bonnet', 'Vincent', ''], ['Busy', 'Maxime', ''], ['Labaye', 'Thierry', ''], ['Besombes', 'Michel', ''], ['Courtois', 'Sebastien', ''], ['Lagrue', 'Edouard', '']]

2009.08725

Jongho Park

Chang-Ock Lee, Eun-Hee Park, and Jongho Park

Correction to: A dual iterative substructuring method with a small penalty parameter

6 pages, 0 figure

J. Korean Math. Soc. 58 (2021) 791--797

10.4134/JKMS.j200505

math.NA cs.NA

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

In this corrigendum, we offer a correction to [J. Korean. Math. Soc., 54 (2017), pp. 461--477]. We construct a counterexample for the strengthened Cauchy--Schwarz inequality used in the original paper. In addition, we provide a new proof for Lemma 5 of the original paper, an estimate for the extremal eigenvalues of the standard unpreconditioned FETI-DP dual operator.

[{'version': 'v1', 'created': 'Fri, 18 Sep 2020 09:59:54 GMT'}]

2021-05-05

[['Lee', 'Chang-Ock', ''], ['Park', 'Eun-Hee', ''], ['Park', 'Jongho', '']]

1805.09140

Juliao Braga

Lucas Andrade, Juliao Braga, Stefany Pereira, Rafael Roque, Marcelo Santos

In-Person and Remote Participation Review at IETF: Collaborating Without Borders

11 pages, To be publish Annals of CSBC 2017 July, Natal, Brazil

cs.CY

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The IETF has been acting as one of the main actors when discussing standardization of protocols and good practices on the Internet. Collaborating with the IETF community can be complex and distant for many researchers and industry members because of the financial aspect to travel to the meeting. However, it notes the collaboration between industry and academia is actively and progressively developing and refining standards within the IETF. One of the incentives for the increased participation in IETF meetings is because it is being transmitted in real time since 2015, allowing for voice and chat interaction of remote participants. Thus, in this paper, we have as objectives to give a brief vision about how to collaborate with the IETF and to analyze the importance of this new form of participation of the face-to-face meetings that has been growing in recent years.

[{'version': 'v1', 'created': 'Tue, 15 May 2018 15:09:18 GMT'}]

2018-05-24

[['Andrade', 'Lucas', ''], ['Braga', 'Juliao', ''], ['Pereira', 'Stefany', ''], ['Roque', 'Rafael', ''], ['Santos', 'Marcelo', '']]

2103.03500

Mark Zhao

Mark Zhao, Mingyu Gao, and Christos Kozyrakis

ShEF: Shielded Enclaves for Cloud FPGAs

10.1145/3503222.3507733

cs.CR cs.AR

http://creativecommons.org/licenses/by/4.0/

FPGAs are now used in public clouds to accelerate a wide range of applications, including many that operate on sensitive data such as financial and medical records. We present ShEF, a trusted execution environment (TEE) for cloud-based reconfigurable accelerators. ShEF is independent from CPU-based TEEs and allows secure execution under a threat model where the adversary can control all software running on the CPU connected to the FPGA, has physical access to the FPGA, and can compromise the FPGA interface logic of the cloud provider. ShEF provides a secure boot and remote attestation process that relies solely on existing FPGA mechanisms for root of trust. It also includes a Shield component that provides secure access to data while the accelerator is in use. The Shield is highly customizable and extensible, allowing users to craft a bespoke security solution that fits their accelerator's memory access patterns, bandwidth, and security requirements at minimum performance and area overheads. We describe a prototype implementation of ShEF for existing cloud FPGAs, map ShEF to a performant and secure storage application, and measure the performance benefits of customizable security using five additional accelerators.

[{'version': 'v1', 'created': 'Fri, 5 Mar 2021 07:02:26 GMT'}, {'version': 'v2', 'created': 'Fri, 28 Jan 2022 00:01:04 GMT'}]

2022-01-31

[['Zhao', 'Mark', ''], ['Gao', 'Mingyu', ''], ['Kozyrakis', 'Christos', '']]

2011.05463

Gasper Begus

Ga\v{s}per Begu\v{s}

Deep Sound Change: Deep and Iterative Learning, Convolutional Neural Networks, and Language Change

cs.CL cs.SD eess.AS

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

This paper proposes a framework for modeling sound change that combines deep learning and iterative learning. Acquisition and transmission of speech is modeled by training generations of Generative Adversarial Networks (GANs) on unannotated raw speech data. The paper argues that several properties of sound change emerge from the proposed architecture. GANs (Goodfellow et al. 2014 arXiv:1406.2661, Donahue et al. 2019 arXiv:1705.07904) are uniquely appropriate for modeling language change because the networks are trained on raw unsupervised acoustic data, contain no language-specific features and, as argued in Begu\v{s} (2020 arXiv:2006.03965), encode phonetic and phonological representations in their latent space and generate linguistically informative innovative data. The first generation of networks is trained on the relevant sequences in human speech from TIMIT. The subsequent generations are not trained on TIMIT, but on generated outputs from the previous generation and thus start learning from each other in an iterative learning task. The initial allophonic distribution is progressively being lost with each generation, likely due to pressures from the global distribution of aspiration in the training data. The networks show signs of a gradual shift in phonetic targets characteristic of a gradual phonetic sound change. At endpoints, the outputs superficially resemble a phonological change -- rule loss.

[{'version': 'v1', 'created': 'Tue, 10 Nov 2020 23:49:09 GMT'}, {'version': 'v2', 'created': 'Wed, 22 Sep 2021 04:59:52 GMT'}]

2021-09-23

[['Beguš', 'Gašper', '']]

0907.4653

Yao Yu

Athina P. Petropulu, Yao Yu and H. Vincent Poor

Distributed MIMO radar using compressive sampling

Proc. 42th Asilomar Conf.Signals, Syst. Comput, pp. 203 - 207, Nov. 2008

cs.IT math.IT

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

A distributed MIMO radar is considered, in which the transmit and receive antennas belong to nodes of a small scale wireless network. The transmit waveforms could be uncorrelated, or correlated in order to achieve a desirable beampattern. The concept of compressive sampling is employed at the receive nodes in order to perform direction of arrival (DOA) estimation. According to the theory of compressive sampling, a signal that is sparse in some domain can be recovered based on far fewer samples than required by the Nyquist sampling theorem. The DOAs of targets form a sparse vector in the angle space, and therefore, compressive sampling can be applied for DOA estimation. The proposed approach achieves the superior resolution of MIMO radar with far fewer samples than other approaches. This is particularly useful in a distributed scenario, in which the results at each receive node need to be transmitted to a fusion center.

[{'version': 'v1', 'created': 'Mon, 27 Jul 2009 15:14:10 GMT'}]

2009-07-28

[['Petropulu', 'Athina P.', ''], ['Yu', 'Yao', ''], ['Poor', 'H. Vincent', '']]

2004.06644

Karl-Ludwig Besser

Karl-Ludwig Besser, Eduard A. Jorswieck

Bounds on the Secrecy Outage Probability for Dependent Fading Channels

Accepted for publication in IEEE Transactions on Communications

IEEE Transactions on Communications, vol. 69, no. 1, pp. 443-456, Jan. 2021

10.1109/TCOMM.2020.3026654

cs.IT math.IT

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The amount of sensitive data, which is transmitted wirelessly will increase with future technologies. This raises many questions about secure data transmission. Besides cryptography, information-theoretic security gained increasing attention over the recent years. Among others, it deals with the problem of secure data transmission on the physical layer to a legitimate receiver (Bob) in the presence of an eavesdropper (Eve). In this work, we investigate upper and lower bounds on the secrecy outage probability for slowly-fading wiretap channels with an arbitrary dependency structure between the fading channels to Bob and Eve. Both cases of absence of channel-state information at the transmitter (CSI-T) and availability of CSI-T of only the main channel to the legitimate receiver are considered. Furthermore, we derive explicit expressions for the upper and lower bounds for Rayleigh fading and compare them to the case of independent channels. The joint distribution of the legitimate and eavesdropper channels has a tremendous impact on the achievable secrecy outage probability. The bounds enable developing guaranteed secrecy schemes by only measuring the marginal channel distributions.

[{'version': 'v1', 'created': 'Tue, 14 Apr 2020 16:38:30 GMT'}, {'version': 'v2', 'created': 'Mon, 21 Sep 2020 13:15:47 GMT'}]

2021-01-18

[['Besser', 'Karl-Ludwig', ''], ['Jorswieck', 'Eduard A.', '']]

1703.07139

Panos Alevizos

Panos N. Alevizos and Aggelos Bletsas

Scatter Radio Receivers for Extended Range Environmental Sensing WSNs

in Proceeding of IEEE Communications Workshop, May 2016, Nafplio, Greece

cs.NI

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Backscatter communication, relying on the reflection principle, constitutes a promising-enabling technology for lowcost, large-scale, ubiquitous sensor networking. This work makes an overview of the state-of-the-art coherent and noncoherent scatter radio receivers that account for the peculiar signal model consisting of several microwave and communication parameters.

[{'version': 'v1', 'created': 'Tue, 21 Mar 2017 10:49:50 GMT'}]

2017-03-22

[['Alevizos', 'Panos N.', ''], ['Bletsas', 'Aggelos', '']]

1401.3999

Nuno de Sousa

N. de Sousa, J.J. S\'aenz, A. Garc\'ia-Mart\'in, L.S. Froufe-P\'erez, M.I. Marqu\'es

Effect of long range spatial correlations on the lifetime statistics of an emitter in a two-dimensional disordered lattice

6 pages, 5 figures

10.1103/PhysRevA.89.063830

physics.optics

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The effect of spatial correlations on the Purcell effect in a bidimensional dispersion of resonant nanoparticles is analyzed. We perform extensive calculations on the fluorescence decay rate of a point emitter embedded in a system of nanoparticles statistically distributed according to a simple 2D lattice-gas model near the critical point. For short-range correlations (high temperature thermalization) the Purcell factors present a long-tailed statistic which evolves towards a bimodal distribution when approaching the critical point where the spatial correlation length diverges. Our results suggest long-range correlations as a possible origin of the large fluctuations of experimental decay rates in disordered metal films.

[{'version': 'v1', 'created': 'Thu, 16 Jan 2014 11:55:52 GMT'}, {'version': 'v2', 'created': 'Tue, 15 Apr 2014 09:28:35 GMT'}, {'version': 'v3', 'created': 'Tue, 10 Jun 2014 09:37:21 GMT'}]

2015-06-18

[['de Sousa', 'N.', ''], ['Sáenz', 'J. J.', ''], ['García-Martín', 'A.', ''], ['Froufe-Pérez', 'L. S.', ''], ['Marqués', 'M. I.', '']]

2111.02402

Damiano Perri

Priscilla Benedetti and Damiano Perri and Marco Simonetti and Osvaldo Gervasi and Gianluca Reali and Mauro Femminella

Skin Cancer Classification using Inception Network and Transfer Learning

International Conference on Computational Science and Its Applications, ICCSA 2020

LNCS, volume 12249, 2020

10.1007/978-3-030-58799-4_39

eess.IV cs.CV cs.LG

http://creativecommons.org/licenses/by/4.0/

Medical data classification is typically a challenging task due to imbalance between classes. In this paper, we propose an approach to classify dermatoscopic images from HAM10000 (Human Against Machine with 10000 training images) dataset, consisting of seven imbalanced types of skin lesions, with good precision and low resources requirements. Classification is done by using a pretrained convolutional neural network. We evaluate the accuracy and performance of the proposal and illustrate possible extensions.

[{'version': 'v1', 'created': 'Wed, 3 Nov 2021 01:50:52 GMT'}]

2021-11-05

[['Benedetti', 'Priscilla', ''], ['Perri', 'Damiano', ''], ['Simonetti', 'Marco', ''], ['Gervasi', 'Osvaldo', ''], ['Reali', 'Gianluca', ''], ['Femminella', 'Mauro', '']]

1303.0102

Lyudmyla Barannyk

Lyudmyla L. Barannyk and Alexander Panchenko

Optimizing performance of the deconvolution model reduction for large ODE systems

29 pages, 30 figures

math-ph cond-mat.dis-nn math.CA math.MP math.NA physics.comp-ph

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

We investigate the numerical performance of the regularized deconvolution closure introduced recently by the authors. The purpose of the closure is to furnish constitutive equations for Irwing-Kirkwood-Noll procedure, a well known method for deriving continuum balance equations from the Newton's equations of particle dynamics. A version of this procedure used in the paper relies on spatial averaging developed by Hardy, and independently by Murdoch and Bedeaux. The constitutive equations for the stress are given as a sum of several operator terms acting on the mesoscale average density and velocity. Each term is a "convolution sandwich" containing the deconvolution operator, a composition or a product operator, and the convolution (averaging) operator. Deconvolution is constructed using filtered regularization methods from the theory of ill-posed problems. The purpose of regularization is to ensure numerical stability. The particular technique used for numerical experiments is truncated singular value decomposition (SVD). The accuracy of the constitutive equations depends on several parameters: the choice of the averaging window function, the value of the mesoscale resolution parameter, scale separation, the level of truncation of singular values, and the level of spectral filtering of the averages. We conduct numerical experiments to determine the effect of each parameter on the accuracy and efficiency of the method. Partial error estimates are also obtained.

[{'version': 'v1', 'created': 'Fri, 1 Mar 2013 07:17:28 GMT'}]

2013-03-04

[['Barannyk', 'Lyudmyla L.', ''], ['Panchenko', 'Alexander', '']]

0803.4508

Arnab Das

Arnab Das, Bikas K. Chakrabarti

Approaching the Ground State of a Quantum Spin Glass using a Zero-Temperature Quantum Monte Carlo

8 pages, 6 figs

10.1103/PhysRevE.78.061121

quant-ph cond-mat.stat-mech physics.comp-ph

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Here we discuss the annealing behavior of an infinite-range $\pm J$ Ising spin glass in presence of a transverse field using a zero-temperature quantum Monte Carlo. Within the simulation scheme, we demonstrate that quantum annealing not only helps finding the ground state of a classical spin glass, but can also help simulating the ground state of a quantum spin glass, in particularly, when the transverse field is low, much more efficiently.

[{'version': 'v1', 'created': 'Mon, 31 Mar 2008 17:48:13 GMT'}]

2009-11-13

[['Das', 'Arnab', ''], ['Chakrabarti', 'Bikas K.', '']]

0905.4950

Daniel Goldman

Chen Li, Paul B. Umbanhowar, Haldun Komsuoglu, Daniel E. Koditschek, Daniel I. Goldman

Sensitive dependence of the motion of a legged robot on granular media

4 figures

Proceedings of the National Academy of Sciences (2009), 106 (9), 3029-3034

10.1073/pnas.0809095106

physics.bio-ph cond-mat.other cond-mat.soft q-bio.QM

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Legged locomotion on flowing ground ({\em e.g.} granular media) is unlike locomotion on hard ground because feet experience both solid- and fluid-like forces during surface penetration. Recent bio-inspired legged robots display speed relative to body size on hard ground comparable to high performing organisms like cockroaches but suffer significant performance loss on flowing materials like sand. In laboratory experiments we study the performance (speed) of a small (2.3 kg) six-legged robot, SandBot, as it runs on a bed of granular media (1 mm poppy seeds). For an alternating tripod gait on the granular bed, standard gait control parameters achieve speeds at best two orders of magnitude smaller than the 2 body lengths/s ($\approx 60$ cm/s) for motion on hard ground. However, empirical adjustment of these control parameters away from the hard ground settings, restores good performance, yielding top speeds of 30 cm/s. Robot speed depends sensitively on the packing fraction $\phi$ and the limb frequency $\omega$, and a dramatic transition from rotary walking to slow swimming occurs when $\phi$ becomes small enough and/or $\omega$ large enough. We propose a kinematic model of the rotary walking mode based on generic features of penetration and slip of a curved limb in granular media. The model captures the dependence of robot speed on limb frequency and the transition between walking and swimming modes but highlights the need for a deeper understanding of the physics of granular media.

[{'version': 'v1', 'created': 'Fri, 29 May 2009 19:37:53 GMT'}]

2021-05-20

[['Li', 'Chen', ''], ['Umbanhowar', 'Paul B.', ''], ['Komsuoglu', 'Haldun', ''], ['Koditschek', 'Daniel E.', ''], ['Goldman', 'Daniel I.', '']]

1709.09215

Zoya Bylinskii

Zoya Bylinskii, Sami Alsheikh, Spandan Madan, Adria Recasens, Kimberli Zhong, Hanspeter Pfister, Fredo Durand, Aude Oliva

Understanding Infographics through Textual and Visual Tag Prediction

cs.CV

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

We introduce the problem of visual hashtag discovery for infographics: extracting visual elements from an infographic that are diagnostic of its topic. Given an infographic as input, our computational approach automatically outputs textual and visual elements predicted to be representative of the infographic content. Concretely, from a curated dataset of 29K large infographic images sampled across 26 categories and 391 tags, we present an automated two step approach. First, we extract the text from an infographic and use it to predict text tags indicative of the infographic content. And second, we use these predicted text tags as a supervisory signal to localize the most diagnostic visual elements from within the infographic i.e. visual hashtags. We report performances on a categorization and multi-label tag prediction problem and compare our proposed visual hashtags to human annotations.

[{'version': 'v1', 'created': 'Tue, 26 Sep 2017 18:45:28 GMT'}]

2017-09-28

[['Bylinskii', 'Zoya', ''], ['Alsheikh', 'Sami', ''], ['Madan', 'Spandan', ''], ['Recasens', 'Adria', ''], ['Zhong', 'Kimberli', ''], ['Pfister', 'Hanspeter', ''], ['Durand', 'Fredo', ''], ['Oliva', 'Aude', '']]

1405.6235

Edward J. Stephenson

Z. Bagdasarian, S. Bertelli, D. Chiladze, G. Ciullo, J. Dietrich, S. Dymov, D. Eversmann, G. Fanourakis, M. Gaisser, R. Gebel, B. Gou, G. Guidoboni, V. Hejny, A. Kacharava, V. Kamerdzhiev, A. Lehrach, P. Lenisa, B. Lorentz, L. Magallanes, R. Maier, D. Mchedlishvili, W.M. Morse, A. Nass, D. Oellers, A. Pesce, D. Prasuhn, J. Pretz, F. Rathmann, V. Shmakova, Y.K. Semertzidis, E.J. Stephenson, H. Stockhorst, H. Str\"oher, R. Talman, P. Th\"orngren Engblom, Yu. Valdau, C. Weidemann, and P. W\"ustner

Measuring the Polarization of a Rapidly Precessing Deuteron Beam

28 pages, 15 figures, prepared for Physical Review ST - Accelerators and Beams

Phys. Rev, STAB 17 (2014) 052803

10.1103/PhysRevSTAB.17.052803

physics.acc-ph

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

This paper describes a time-marking system that enables a measurement of the in-plane (horizontal) polarization of a 0.97-GeV/c deuteron beam circulating in the Cooler Synchrotron (COSY) at the Forschungszentrum J\"ulich. The clock time of each polarimeter event is used to unfold the 120-kHz spin precession and assign events to bins according to the direction of the horizontal polarization. After accumulation for one or more seconds, the down-up scattering asymmetry can be calculated for each direction and matched to a sinusoidal function whose magnitude is proportional to the horizontal polarization. This requires prior knowledge of the spin tune or polarization precession rate. An initial estimate is refined by re-sorting the events as the spin tune is adjusted across a narrow range and searching for the maximum polarization magnitude. The result is biased toward polarization values that are too large, in part because of statistical fluctuations but also because sinusoidal fits to even random data will produce sizeable magnitudes when the phase is left free to vary. An analysis procedure is described that matches the time dependence of the horizontal polarization to templates based on emittance-driven polarization loss while correcting for the positive bias. This information will be used to study ways to extend the horizontal polarization lifetime by correcting spin tune spread using ring sextupole fields and thereby to support the feasibility of searching for an intrinsic electric dipole moment using polarized beams in a storage ring. This paper is a combined effort of the Storage Ring EDM Collaboration and the JEDI Collaboration.

[{'version': 'v1', 'created': 'Fri, 23 May 2014 21:08:39 GMT'}]

2014-10-24

[['Bagdasarian', 'Z.', ''], ['Bertelli', 'S.', ''], ['Chiladze', 'D.', ''], ['Ciullo', 'G.', ''], ['Dietrich', 'J.', ''], ['Dymov', 'S.', ''], ['Eversmann', 'D.', ''], ['Fanourakis', 'G.', ''], ['Gaisser', 'M.', ''], ['Gebel', 'R.', ''], ['Gou', 'B.', ''], ['Guidoboni', 'G.', ''], ['Hejny', 'V.', ''], ['Kacharava', 'A.', ''], ['Kamerdzhiev', 'V.', ''], ['Lehrach', 'A.', ''], ['Lenisa', 'P.', ''], ['Lorentz', 'B.', ''], ['Magallanes', 'L.', ''], ['Maier', 'R.', ''], ['Mchedlishvili', 'D.', ''], ['Morse', 'W. M.', ''], ['Nass', 'A.', ''], ['Oellers', 'D.', ''], ['Pesce', 'A.', ''], ['Prasuhn', 'D.', ''], ['Pretz', 'J.', ''], ['Rathmann', 'F.', ''], ['Shmakova', 'V.', ''], ['Semertzidis', 'Y. K.', ''], ['Stephenson', 'E. J.', ''], ['Stockhorst', 'H.', ''], ['Ströher', 'H.', ''], ['Talman', 'R.', ''], ['Engblom', 'P. Thörngren', ''], ['Valdau', 'Yu.', ''], ['Weidemann', 'C.', ''], ['Wüstner', 'P.', '']]

1605.06377

Christian Gruhl

Dominik Fisch, Christian Gruhl, Edgar Kalkowski, Bernhard Sick, Seppo J. Ovaska

Towards Automation of Knowledge Understanding: An Approach for Probabilistic Generative Classifiers

29 pages with 9 figures and 4 tables. Currently under review for Information Sciences

cs.LG cs.AI

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

After data selection, pre-processing, transformation, and feature extraction, knowledge extraction is not the final step in a data mining process. It is then necessary to understand this knowledge in order to apply it efficiently and effectively. Up to now, there is a lack of appropriate techniques that support this significant step. This is partly due to the fact that the assessment of knowledge is often highly subjective, e.g., regarding aspects such as novelty or usefulness. These aspects depend on the specific knowledge and requirements of the data miner. There are, however, a number of aspects that are objective and for which it is possible to provide appropriate measures. In this article we focus on classification problems and use probabilistic generative classifiers based on mixture density models that are quite common in data mining applications. We define objective measures to assess the informativeness, uniqueness, importance, discrimination, representativity, uncertainty, and distinguishability of rules contained in these classifiers numerically. These measures not only support a data miner in evaluating results of a data mining process based on such classifiers. As we will see in illustrative case studies, they may also be used to improve the data mining process itself or to support the later application of the extracted knowledge.

[{'version': 'v1', 'created': 'Fri, 20 May 2016 14:34:49 GMT'}]

2016-05-23

[['Fisch', 'Dominik', ''], ['Gruhl', 'Christian', ''], ['Kalkowski', 'Edgar', ''], ['Sick', 'Bernhard', ''], ['Ovaska', 'Seppo J.', '']]

1908.00390

Ian Roper

Ian P. E. Roper, S. Jon Chapman, Colin P. Please

The effect of mechanical stress on lithium distribution and geometry optimisation for multi-material lithium-ion anodes

21 pages, 13 figures

cond-mat.mtrl-sci physics.app-ph

http://creativecommons.org/licenses/by/4.0/

A model is presented for predicting the open-circuit voltage (OCV) and lithium distribution within lithium-ion anodes containing multiple materials, coupling linear elasticity with a stress-dependent chemical potential. The model is applied to a spherical radially-symmetric nano-particle with a silicon core and a graphite shell, highlighting the large effect on lithium distribution and OCV caused by the stress-coupling. Various performance measures based on the expanded volume, the amount of lithium intercalated and the maximum stress induced, are calculated for a silicon core with a graphite shell to enable optimisation of the volume of the silicon core.

[{'version': 'v1', 'created': 'Thu, 4 Jul 2019 16:02:59 GMT'}]

2019-08-02

[['Roper', 'Ian P. E.', ''], ['Chapman', 'S. Jon', ''], ['Please', 'Colin P.', '']]

1006.0358

Deepak Mathur

J. S. D'Souza, J. A. Dharmdhikari, A. K. Dharmdhikair, B. J. Rao, and D. Mathur

Effect of intense, ultrashort laser pulses on DNA plasmids in their native state: strand breakages induced by {\it in-situ} electrons

Part of an invited paper presented at the 3rd International Symposium on Filamentation, 31 May - 5 June, 2010, Crete, Greece

physics.bio-ph cond-mat.soft physics.chem-ph physics.optics

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Single strand breaks are induced in DNA plasmids, pBR322 and pUC19, in aqueous media by intense ultrashort laser pulses (820 nm wavelength, 45 fs pulse duration, 1 kHz repetition rate) at intensities of 1-12 TW cm$^{-2}$. The intense laser radiation generates, {\it in situ}, electrons that induce transformation of supercoiled DNA into relaxed DNA. The extent of electron-mediated relaxation of DNA structure is quantified. Introduction of electron and radical scavengers inhibits DNA damage.

[{'version': 'v1', 'created': 'Wed, 2 Jun 2010 12:31:17 GMT'}]

2010-06-03

[["D'Souza", 'J. S.', ''], ['Dharmdhikari', 'J. A.', ''], ['Dharmdhikair', 'A. K.', ''], ['Rao', 'B. J.', ''], ['Mathur', 'D.', '']]

1103.5002

David Vallet David Vallet

Blaz Fortuna, Dunja Mladenic, Marko Grobelnik

User Modeling Combining Access Logs, Page Content and Semantics

1st International Workshop on Usage Analysis and the Web of Data (USEWOD2011) in the 20th International World Wide Web Conference (WWW2011), Hyderabad, India, March 28th, 2011

WWW2011USEWOD/2011/formlagro

cs.IR cs.AI cs.HC

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The paper proposes an approach to modeling users of large Web sites based on combining different data sources: access logs and content of the accessed pages are combined with semantic information about the Web pages, the users and the accesses of the users to the Web site. The assumption is that we are dealing with a large Web site providing content to a large number of users accessing the site. The proposed approach represents each user by a set of features derived from the different data sources, where some feature values may be missing for some users. It further enables user modeling based on the provided characteristics of the targeted user subset. The approach is evaluated on real-world data where we compare performance of the automatic assignment of a user to a predefined user segment when different data sources are used to represent the users.

[{'version': 'v1', 'created': 'Fri, 25 Mar 2011 15:49:03 GMT'}]

2011-03-28

[['Fortuna', 'Blaz', ''], ['Mladenic', 'Dunja', ''], ['Grobelnik', 'Marko', '']]

2004.05964

Shusei Eshima

Shusei Eshima, Kosuke Imai and Tomoya Sasaki

Keyword Assisted Topic Models

cs.CL stat.AP stat.ME

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

In recent years, fully automated content analysis based on probabilistic topic models has become popular among social scientists because of their scalability. The unsupervised nature of the models makes them suitable for exploring topics in a corpus without prior knowledge. However, researchers find that these models often fail to measure specific concepts of substantive interest by inadvertently creating multiple topics with similar content and combining distinct themes into a single topic. In this paper, we empirically demonstrate that providing a small number of keywords can substantially enhance the measurement performance of topic models. An important advantage of the proposed keyword assisted topic model (keyATM) is that the specification of keywords requires researchers to label topics prior to fitting a model to the data. This contrasts with a widespread practice of post-hoc topic interpretation and adjustments that compromises the objectivity of empirical findings. In our application, we find that keyATM provides more interpretable results, has better document classification performance, and is less sensitive to the number of topics than the standard topic models. Finally, we show that keyATM can also incorporate covariates and model time trends. An open-source software package is available for implementing the proposed methodology.

[{'version': 'v1', 'created': 'Mon, 13 Apr 2020 14:35:28 GMT'}, {'version': 'v2', 'created': 'Wed, 10 Mar 2021 15:24:52 GMT'}, {'version': 'v3', 'created': 'Fri, 3 Feb 2023 00:29:28 GMT'}]

2023-02-06

[['Eshima', 'Shusei', ''], ['Imai', 'Kosuke', ''], ['Sasaki', 'Tomoya', '']]

2006.10695

Kai Yang

Annie Millet, Alex D Rodriguez, Svetlana Roudenko and Kai Yang

Behavior of solutions to the 1D focusing stochastic nonlinear Schr\"odinger equation with spatially correlated noise

Stochastic Partial Differential Equations, Analysis and Computations, 2021

10.1007/s40072-021-00191-0

math.AP cs.NA math.NA math.PR

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

We study the focusing stochastic nonlinear Schr\"odinger equation in one spatial dimension with multiplicative noise, driven by a Wiener process white in time and colored in space, in the $L^2$-critical and supercritical cases. The mass ($L^2$-norm) is conserved due to the multiplicative noise defined via the Stratonovich integral, the energy (Hamiltonian) is not preserved. We first investigate how the energy is affected by various spatially correlated random perturbations. We then study the influence of the noise on the global dynamics measuring the probability of blow-up versus scattering behavior depending on various parameters of correlation kernels. Finally, we study the effect of the spatially correlated noise on the blow-up behavior, and conclude that such random perturbations do not influence the blow-up dynamics, except for shifting of the blow-up center location. This is similar to what we observed in [32] for a space-time white driving noise.

[{'version': 'v1', 'created': 'Thu, 18 Jun 2020 17:29:12 GMT'}]

2022-10-11

[['Millet', 'Annie', ''], ['Rodriguez', 'Alex D', ''], ['Roudenko', 'Svetlana', ''], ['Yang', 'Kai', '']]

1405.1229

Shahab Tasharrofi

Shahab Tasharrofi and Eugenia Ternovska

Three Semantics for Modular Systems

Current paper appears in the Proceedings of the 15th International Workshop on Non-Monotonic Reasoning (NMR 2014)

cs.LO

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

In this paper, we further develop the framework of Modular Systems that lays model-theoretic foundations for combining different declarative languages, agents and solvers. We introduce a multi-language logic of modular systems. We define two novel semantics, a structural operational semantics, and an inference-based semantics. We prove the new semantics are equivalent to the original model-theoretic semantics and describe future research directions.

[{'version': 'v1', 'created': 'Tue, 6 May 2014 11:19:32 GMT'}]

2014-05-07

[['Tasharrofi', 'Shahab', ''], ['Ternovska', 'Eugenia', '']]

0811.3536

Damien Chablat

Anatoly Pashkevich (IRCCyN), Damien Chablat (IRCCyN), Philippe Wenger (IRCCyN)

Analyse de la rigidit\'e des machines outils 3 axes d'architecture parall\`ele hyperstatique

5eme Assises Machines et Usinage \`a grande vitesse, Nantes : France (2008)

cs.RO

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The paper presents a new stiffness modelling method for overconstrained parallel manipulators, which is applied to 3-d.o.f. translational mechanisms. It is based on a multidimensional lumped-parameter model that replaces the link flexibility by localized 6-d.o.f. virtual springs. In contrast to other works, the method includes a FEA-based link stiffness evaluation and employs a new solution strategy of the kinetostatic equations, which allows computing the stiffness matrix for the overconstrained architectures and for the singular manipulator postures. The advantages of the developed technique are confirmed by application examples, which deal with comparative stiffness analysis of two translational parallel manipulators.

[{'version': 'v1', 'created': 'Fri, 21 Nov 2008 13:47:01 GMT'}]

2008-11-24

[['Pashkevich', 'Anatoly', '', 'IRCCyN'], ['Chablat', 'Damien', '', 'IRCCyN'], ['Wenger', 'Philippe', '', 'IRCCyN']]

1807.02716

Yimin Liu

Yimin Liu, Wenyue Sun, Louis J. Durlofsky

A Deep-Learning-Based Geological Parameterization for History Matching Complex Models

stat.ML cs.CV cs.LG physics.geo-ph

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

A new low-dimensional parameterization based on principal component analysis (PCA) and convolutional neural networks (CNN) is developed to represent complex geological models. The CNN-PCA method is inspired by recent developments in computer vision using deep learning. CNN-PCA can be viewed as a generalization of an existing optimization-based PCA (O-PCA) method. Both CNN-PCA and O-PCA entail post-processing a PCA model to better honor complex geological features. In CNN-PCA, rather than use a histogram-based regularization as in O-PCA, a new regularization involving a set of metrics for multipoint statistics is introduced. The metrics are based on summary statistics of the nonlinear filter responses of geological models to a pre-trained deep CNN. In addition, in the CNN-PCA formulation presented here, a convolutional neural network is trained as an explicit transform function that can post-process PCA models quickly. CNN-PCA is shown to provide both unconditional and conditional realizations that honor the geological features present in reference SGeMS geostatistical realizations for a binary channelized system. Flow statistics obtained through simulation of random CNN-PCA models closely match results for random SGeMS models for a demanding case in which O-PCA models lead to significant discrepancies. Results for history matching are also presented. In this assessment CNN-PCA is applied with derivative-free optimization, and a subspace randomized maximum likelihood method is used to provide multiple posterior models. Data assimilation and significant uncertainty reduction are achieved for existing wells, and physically reasonable predictions are also obtained for new wells. Finally, the CNN-PCA method is extended to a more complex non-stationary bimodal deltaic fan system, and is shown to provide high-quality realizations for this challenging example.

[{'version': 'v1', 'created': 'Sat, 7 Jul 2018 20:34:04 GMT'}]

2018-07-11

[['Liu', 'Yimin', ''], ['Sun', 'Wenyue', ''], ['Durlofsky', 'Louis J.', '']]

2001.00453

Supriya Sarker

Supriya Sarker, Md. Sajedur Rahman, Mohammad Nazmus Sakib

An Approach Towards Intelligent Accident Detection, Location Tracking and Notification System

The 3rd IEEE International Conference on Telecommunications and Photonics (ICTP) 2019

cs.OH cs.HC

http://creativecommons.org/licenses/by-sa/4.0/

Advancement in transportation system has boosted speed of our lives. Meantime, road traffic accident is a major global health issue resulting huge loss of lives, properties and valuable time. It is considered as one of the reasons of highest rate of death nowadays. Accident creates catastrophic situation for victims, especially accident occurs in highways imposes great adverse impact on large numbers of victims. In this paper, we develop an intelligent accident detection, location tracking and notification system that detects an accident immediately when it takes place. Global Positioning System (GPS) device finds the exact location of accident. Global System for Mobile (GSM) module sends a notification message including the link of location in the google map to the nearest police control room and hospital so that they can visit the link, find out the shortest route of the accident spot and take initiatives to speed up the rescue process.

[{'version': 'v1', 'created': 'Sun, 29 Dec 2019 14:15:18 GMT'}]

2020-01-03

[['Sarker', 'Supriya', ''], ['Rahman', 'Md. Sajedur', ''], ['Sakib', 'Mohammad Nazmus', '']]

1912.06298

Fatemeh Pourahmadian

Fatemeh Pourahmadian and Houssem Haddar

Differential tomography of micromechanical evolution in elastic materials of unknown micro/macrostructure

math.NA cs.NA

http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Differential evolution indicators are introduced for 3D spatiotemporal imaging of micromechanical processes in complex materials where progressive variations due to manufacturing and/or aging are housed in a highly scattering background of a-priori unknown or uncertain structure. In this vein, a three-tier imaging platform is established where: (1) the domain is periodically (or continuously) subject to illumination and sensing in an arbitrary configuration; (2) sequential sets of measured data are deployed to distill segment-wise scattering signatures of the domain's internal structure through carefully constructed, non-iterative solutions to the scattering equation; and (3) the resulting solution sequence is then used to rigorously construct an imaging functional carrying appropriate invariance with respect to the unknown stationary components of the background e.g., pre-existing interstitial boundaries and bubbles. This gives birth to differential indicators that specifically recover the 3D support of micromechanical evolution within a network of unknown scatterers. The direct scattering problem is formulated in the frequency domain where the background is comprised of a random distribution of monolithic fragments. The constituents are connected via highly heterogeneous interfaces of unknown elasticity and dissipation which are subject to spatiotemporal evolution. The support of internal boundaries are sequentially illuminated by a set of incident waves and thus-induced scattered fields are captured over a generic observation surface. The performance of the proposed imaging indicator is illustrated through a set of numerical experiments for spatiotemporal reconstruction of progressive damage zones featuring randomly distributed cracks and bubbles.

[{'version': 'v1', 'created': 'Fri, 13 Dec 2019 02:32:38 GMT'}]

2019-12-16

[['Pourahmadian', 'Fatemeh', ''], ['Haddar', 'Houssem', '']]