ppxscal/embedding_network huggingface dataset:
Validation of Cone-Beam CT Measurements of Tumour Burden Using Three-Dimensional Histopathology: Initial Results For a Lumpectomy
Authors: G. M. Clarke, J. G. Mainprize, C. Peressotti, L. Sun, D. Wang, J. T. Zubovits, C. M. Holloway, G. J. Czarnota, M. J. Yaffe
Venue: Proceedings of the 9th international workshop on Digital Mammography (2008)

Tumour size is an important prognostic indicator in breast cancer. This is typically measured as a simple linear diameter, although tumour volume may be a better surrogate of tumour burden. We have been optimizing techniques for three-dimensional histopathology based on digital scanning light microscopy of whole-mount, whole-specimen serial sections. We apply this to validate tumour volume measurements obtained using specimen cone-beam CT imaging. We demonstrate initial results for this technique using one lumpectomy and then show examples of how this technique can serve as a `gateway' to validating emerging functional and molecular imaging modalities.
The Smallest Multistationary Mass-Preserving Chemical Reaction Network
Authors: Anne Shiu
Venue: Proceedings of the 3rd international conference on Algebraic Biology (2008)

Biochemical models that exhibit bistability are of interest to biologists and mathematicians alike. Chemical reaction network theory can provide sufficient conditions for the existence of bistability, and on the other hand can rule out the possibility of multiple steady states. Understanding small networks is important because the existence of multiple steady states in a subnetwork of a biochemical model can sometimes be lifted to establish multistationarity in the larger network. This paper establishes the smallest reversible, mass-preserving network that admits bistability and determines the semi-algebraic set of parameters for which more than one steady state exists.
Learner Modelling in Exploratory Learning for Mathematical Generalisation
Authors: Mihaela Cocea
Venue: Proceedings of the 5th international conference on Adaptive Hypermedia and Adaptive Web-Based Systems (2008)

Exploratory learning supports creative thinking, allowing learners to control their own learning process, whilst it provides them with help and guidance when necessary. This pedagogical approach emphasises learners' active involvement in authentic activities/tasks that simulate real world processes and has been applied to several domains. In this paper we propose a framework for learner modelling that reflects the incremental nature of knowledge construction as learners are engaged in learning mathematical generalisation. We also describe how such a model can potentially support feedback generation.
Method for extraction of information from very small databases
Authors: Martin A. Seitz
Venue:  (2007)

Small databases present unique challenges for the extraction of meaningful information. This is true relative to genetic biological databases where the acquisition of data from animal models is both costly and limited. However, we have a choice; either find a method for extracting information from this small database or ignore the information that has been acquired at considerable cost and effort. This dissertation presents an archetype sentinel method for extracting meaningful information for this very important area of research. A clustering method was developed to identify 'sentinel' subjects from a very small data base. This method applies two computational techniques to create a mechanism for identifying subjects that are characteristic of one of two groups. We used a biological database which contains parameters (phenotypes) characterizing normal Brown Norway (BN) rats and hypertensive salt sensitive consomic 20 (SS20BN) rats. Fuzzy Cluster Means (FCM) is used to distinguish a very small group of archetype sentinel subjects from the general population. Archetype sentinels are those subjects that are most often classified correctly within a limited portion of the entire collection of biomedical phenotypes. The archetype sentinels are then used to train a Neural Network (NN) to classify all subjects. A total of 79 rats were analyzed with the FCM method yielding 6 normal (BN) archetypes and 5 hypertensive (SS20BN) archetype subjects characterized by a total of 39 phenotypes (18 renal and 21 cardiac.) These 11 archetype sentinels then were used as a NN training set to classify the non-archetype sentinel subjects as either normal or hypertensive. All of the archetype sentinels plus 10 of 11 BN and 10 of 10 SS20BN non-archetype rats were properly classified. Overall, roughly 97% of the rats were classified correctly. Results demonstrate that the FCM method can be used to isolate archetype sentinels, which then can be used to train a hardlim perceptron NN to determine classification of unrelated rats with the same genetic background. This approach can be generalized and used to classify small data bases in other applications.
Estimation DOAs of the Coherent Sources Based on Toeplitz Decorrelation
Authors: Xiao-qin Hu, Jian-wen Chen, Hui Chen, Yong-liang Wang
Venue: Proceedings of the 2008 Congress on Image and Signal Processing, Vol. 5 - Volume 05 (2008)

In this paper, a novel method based on Toeplitz decorrelation is proposed to estimate DOAs (direction of arrivals) of the coherent sources. Using the eigenvector corresponding to the largest eigenvalue obtained from the received data covariance matrix, the presented method constructs a new Toeplitz matrix whose rank is equal to the number of sources. The presented method fully uses the property of the eigenvector corresponding to the largest eigenvalue to estimate coherent sources. This approach doesn't lose the array aperture and can estimate more coherent sources without spatial smoothing and weighting. In comparison with the conventional decorrelation algorithms, the method offers better estimation performance for coherent sources, especially at low SNR. Theoretical analyses and simulation experiments demonstrate the effectiveness of the proposed method for estimation DOAs of the coherent sources.
Weighted Latent Dirichlet Allocation for Cluster Ensemble
Authors: Hongjun Wang, Zhishu Li, Yang Cheng
Venue: Proceedings of the 2008 Second International Conference on Genetic and Evolutionary Computing (2008)

The paper introduces weighted Distributed Latent Dirichlet allocation for cluster ensemble. The idea is that for cluster ensemble we think every base clustering is not equally important, and thus we give the different weight to each base clustering and assume that the results of each base clustering is a multinomial ditribution. First, we state a soft cluster ensemble model of WLDA and the latent variables in WLDA is defined for cluster ensemble. Second, WLDA is inferred with variation approximation and EM algorithmfor WLDA is stated. Third, we choose some dataset of large number of instances for experiment. Compared with MCLA, CSPA and HGPA, WLDA runs a better results and furthermore the outputs of WLDA can show the structure of data points.
Online OVSF Code Assignment with Resource Augmentation
Authors: Francis Y. Chin, Yong Zhang, Hong Zhu
Venue: Proceedings of the 3rd international conference on Algorithmic Aspects in Information and Management (2007)

Orthogonal Variable Spreading Factor (OVSF) code assignment is a fundamental problem in Wideband Code-Division Multiple-Access (W-CDMA) systems, which play an important role in third generation mobile communications. In the OVSF problem, codes must be assigned to incoming code requests, with different data rate requirements, in such a way that they are mutually orthogonal with respect to an OVSF code tree. An OVSF code tree is a complete binary tree in which each node represents a code associated with the combined bandwidths of its two children. To be mutually orthogonal, each leaf-to-root path must contain at most one assigned code. In this paper, we focus on the online version of the OVSF code assignment problem, in the often-studied context of the single cell as well as in the more general context of the whole multi-cell cellular network (for which there are no known results). With the help of 1/8 and 11/8 extra bandwidth resources, we are able to give a 5-competitive algorithm in the single cell and the multi-cell context respectively, which means that the competitive ratio is a constant and not a function of the height of the OVSF tree and thereby improving upon past results.
Development of an Autonomous Rescue Robot Within the USARSim 3D Virtual Environment
Authors: Giuliano Polverari, Daniele Calisi, Alessando Farinelli, Daniele Nardi
Venue: RoboCup 2006: Robot Soccer World Cup X (2006)

The increasing interest towards rescue robotics and the complexity of typical rescue environments make it necessary to use high fidelity 3D simulators during the application development phase. USARSim is an open source high fidelity simulator for rescue environments, based on a commercial game engine. In this paper, we describe the development of an autonomous rescue robot within the USARSim simulation environment. We describe our rescue robotic system and present the extensions we made to USARSim in order to have a satisfying simulation of our robot. Moreover, as a case study, we present an algorithm to avoid obstacles invisible to our laser scanner based mapping process.
Semantic Web Meets ILP: Unconsumated Love, or No Love Lost?
Authors: Frank Harmelen
Venue: Proceedings of the 18th international conference on Inductive Logic Programming (2008)

Even at first glance, ILP and the Semantic Web have much in common. Both are about large volumes of data, both make use of background knowledge , and both use computationally tractable forms of logic. Nevertheless, the actual intersection of the two research areas is very small. In this talk, I will first give a birds eye overview of the Semantic Web programme (its goals, its methods, its achievements to date, and the important open challenges). I will then consider the most obvious use of ILP for the Semantic Web: could ILP be used to learn the ontologies that are such a crucial ingredient in the Semantic Web story? However, as with any result from Machine Learning, such ontologies will not be fully correct and complete. This will require that, from its side, the Semantic Web community must learn how to deal with such partially incomplete and incorrect ontologies. I will present the most recent work in this direction, the efforts to build LarKC, the Large Knowledge, a platform for infinitely scaleable distributed incomplete Semantic Web reasoning. Could the Large Knowledge Collider be the place where ILP and the Semantic Web finally meet?
Tagging for use: an analysis of use-centred resource description
Authors: Luanne Freund, Richard Butterworth
Venue: Proceedings of the second international symposium on Information interaction in context (2008)

This paper discusses use-centred resource description, a practice whereby an information object is assigned metadata that describes what it can be used for, as opposed to what it is. We look at precedents for this practice in the literature and present three cases of use-centred description in diverse information environments. Through analysis and comparison of the cases, we develop a preliminary framework for use-centred resource description.
Congestion control in satellite networks
Authors: John S. Baras
Venue:  (2007)

Due to exponential increases in internet traffic, Active Queue Management (AQM) has been heavily studied by numerous researchers. However, little is known about AQM in satellite networks. A microscopic examination of queueing behavior in satellite networks is conducted to identify problems with applying existing AQM methods. A new AQM method is proposed to overcome the problems and it is validated using a realistic emulation environment and a mathematical model. Three problems that were discovered during the research are discussed in this dissertation. The first problem is oscillatory queueing, which is caused by high buffering due to Performance Enhancing Proxy (PEP) in satellite networks where congestion control after the PEP buffering does not effectively control traffic senders. Existing AQMs that can solve this problem have tail drop queueing that results in consecutive packet drops (global synchronization). A new AQM method called Adaptive Virtual Queue Random Early Detection (AVQRED) is proposed to solve this problem. The second problem is unfair bandwidth sharing caused by inaccurate measurements of per-flow bandwidth usage. AVQRED is enhanced to accurately measure per-flow bandwidth usage to solve this problem without adding much complexity to the algorithm. The third problem is queueing instability caused by buffer flow control where TCP receive windows are adjusted to flow control traffic senders instead of dropping received packets during congestion. Although buffer flow control is quite attractive to satellite networks, queueing becomes unstable because accepting packets instead of dropping them aggravates the congestion level. Furthermore, buffer flow control has abrupt reductions in the TCP receive window size due to high PEP buffering causing more instability. AVQRED with packet drop is proposed to solve this problem. Networks with scarce bandwidth and high propagation delays can not afford to have an unstable AQM. In this research, three problems that are caused by existing AQMs are identified and a new AQM is proposed to solve the problems. This research can be used by the satellite industry to improve gateway performances and provide better end-user experiences.
Learning Support System Based on Note-Taking Method for People with Acquired Visual Disabilities
Authors: Kazuyuki Itou, Baku Kato, Masaru Taniguchi, Toshio Otogawa, Kazuyuki Itoh, Kimiyasu Kiyota, Nobuo Ezaki, Keiichi Uchimura
Venue: Proceedings of the 11th international conference on Computers Helping People with Special Needs (2008)

This study is intended to produce a learning support system for middle-aged people and elderly people with acquired visual disabilities. Our investigation results related to tools of study show that the use of Braille and PCs has decreased in the classes. The first reason is that the number of elderly students has increased. Secondly, finger-reading is difficult for people with diabetic neuropathy. Thirdly, the Japanese kanji transfer system makes the keyboard operation of a PC difficult. We are developing new note-taking systems. One is Braille-type system; the other is a pen-based system. We produced prototypes. Our students used and evaluated them. We are planning to establish a learning support system using these devices.
Localization of mobile users using trajectory matching
Authors: HyungJune Lee, Martin Wicke, Branislav Kusy, Leonidas Guibas
Venue: Proceedings of the first ACM international workshop on Mobile entity localization and tracking in GPS-less environments (2008)

We present an algorithm enabling localization of moving wireless devices in an indoor setting. The method uses only RF signal strength and can be implemented without specialized hardware. The mobility of the users is modeled by learning a function mapping a short history of signal strength values to a 2D position. We use radial basis function (RBF) fitting to learn a reliable estimate of a mobile node's position given its past signal strength measurements. Even though we deal with extremely noisy measurements in a cluttered indoor setting, nodes are not required to be stationary during measurement or learning. We evaluate our algorithm in a real indoor setting using MicaZ motes, achieving an average localization accuracy of 1.3 m. In our experiments, using historical data improves the localization accuracy by almost a factor of two compared to using only the most current measurements.
Optimal Trajectory Planning for Wheeled Mobile Robots Based on Kinematics Singularity
Authors: Luis Gracia, Josep Tornero
Venue: Journal of Intelligent and Robotic Systems (2008)

This research introduces a new optimality criterion for motion planning of wheeled mobile robots based on a cost index that assesses the nearness to singularity of forward and inverse kinematic models. Slip motions, infinite estimation error and impossible control actions are avoided escaping from singularities. In addition, high amplification of wheel velocity errors and high wheel velocity values are also avoided by moving far from the singularity. The proposed cost index can be used directly to complement path-planning and motion-planning techniques (e.g. tree graphs, roadmaps, etc.) in order to select the optimal collision-free path or trajectory among several possible solutions. To illustrate the applications of the proposed approach, an industrial forklift, equivalent to a tricycle-like mobile robot, is considered in a simulated environment. In particular, several results are validated for the proposed optimality criterion, which are extensively compared to those obtained with other classical optimality criteria, such as shortest-path, time-optimal and minimum-energy.
Decentralized concurrency control for real-time collaborative editors
Authors: Abdessamad Imine
Venue: Proceedings of the 8th international conference on New technologies in distributed systems (2008)

Real-time Collaborative Editors (RCE) provide computer support for modifying simultaneously shared documents, such as articles, wiki pages and programming source code, by dispersed users. Due to data replication, Operational Transformation (OT) is considered as the efficient and safe method for consistency maintenance in the literature of collaborative editors. Indeed, it is aimed at ensuring copies convergence even though the users's updates are executed in any order on different copies. Unfortunately, existing OT algorithms often fail to achieve this objective. Moreover, these algorithms have limited scalability with the number of users as they use vector timestamps to enforce causality dependency. In this paper, we present a novel framework for managing collaborative editing work in a scalable and decentralized fashion. It may be deployed easily on P2P networks as it supports dynamic groups where users can leave and join at any time.
Haptic Search for Spheres and Cubes
Authors: Myrthe A. Plaisier, Wouter M. Bergmann Tiest, Astrid M. Kappers
Venue: Proceedings of the 6th international conference on Haptics: Perception, Devices and Scenarios (2008)

If you have multiple objects in your pocket, some are easy to find among the other ones, for instance, when they differ much in material properties or shape. Information on which haptic features stand out among others is valuable for research into the haptic system in general, but also for haptic interface design. In this research we focussed on saliency of shape, by letting subjects search for cubes or spheres. Response times were measured as a function of the number of items. We found that search for a cube among spheres is more efficient than search for a sphere among cubes and that the dynamics of the sliding of the shapes along each other play an important role in haptic search.
Fulfilling Task Dependence Gaps for Workflow Scheduling on Grids
Authors: Luiz F. Bittencourt, Edmundo R. M. Madeira
Venue: Proceedings of the 2007 Third International IEEE Conference on Signal-Image Technologies and Internet-Based System (2007)

The workflow programming paradigm has had a representative growth in the last years. This model is useful to represent flows of control and facilitate the complexity management of processes that have multiple dependent tasks. With the emergence of e-Science, workflow is becoming a standard for management of scientific processes with massive data sets. Within the workflow execution, scheduling of tasks is primordial to provide efficiency and to speed up the process results arrival. In this paper we consider the execution environment as being a computational grid, which is dynamic, non-dedicated, and has heterogeneous resources. We present a strategy for scheduling dependent task processes, dealing with scheduling and execution of more than one process at the same time potentially using resources in common. The algorithm is dynamic and adaptive, rescheduling tasks that are on the queue of resources not presenting good performance. Simulations show that the proposed strategy can give better schedules by enhancing the resources usage.
An Improved Entropy Function and Chaos Optimization Based Scheme for Two-Dimensional Entropic Image Segmentation
Authors: Cheng Ma, Chengshun Jiang
Venue: Computational Intelligence and Security: International Conference, CIS 2006, Guangzhou, China, November 3-6, 2006, Revised Selected Papers (2007)

An improved two-dimensional entropic image segmentation method is presented in this paper. The method makes use of a new entropy function defined in a simple form, which can reduce computational amount notably. And the correctness of the new function is also proved. Then a scheme based on mutative scale chaos optimization is adopted to search for the optimal threshold. The results of simulation illustrate that efficiency of segmentation is improved significantly due to the new entropy function and searching method.
Illumination compensation and normalization in eigenspace-based face recognition: A comparative study of different pre-processing approaches
Authors: Javier Ruiz-del-Solar, Julio Quinteros
Venue: Pattern Recognition Letters (2008)

The aim of this work is to investigate illumination compensation and normalization in eigenspace-based face recognition by carrying out an independent comparative study among several pre-processing algorithms. This research is motivated by the lack of direct and detailed comparisons of those algorithms in equal working conditions. The results of this comparative study intend to be a guide for the developers of face recognitions systems. The study focuses on algorithms with the following properties: (i) general purpose, (ii) no modeling steps or training images required, (iii) simplicity, (iv) high speed, and (v) high performance in terms of recognition rates. Thus, herein five different algorithms are compared, by using them as a pre-processing stage in 16 different eigenspace-based face recognition systems. The comparative study is carried out in a face identification scenario using a large amount of images from the PIE, Yale B and Notre Dame face databases. As a result of this study we concluded that the most suitable algorithms for achieving illumination compensation and normalization in eigenspace-based face recognition are SQI and the modified LBP transform.
Modeling Computational Security in Long-Lived Systems
Authors: Ran Canetti, Ling Cheung, Dilsun Kaynar, Nancy Lynch, Olivier Pereira
Venue: Proceedings of the 19th international conference on Concurrency Theory (2008)

For many cryptographic protocols, security relies on the assumption that adversarial entities have limited computational power. This type of security degrades progressively over the lifetime of a protocol. However, some cryptographic services, such as timestamping services or digital archives, are long-lived in nature; they are expected to be secure and operational for a very long time (i.e. super-polynomial). In such cases, security cannot be guaranteed in the traditional sense: a computationally secure protocol may become insecure if the attacker has a super-polynomial number of interactions with the protocol.This paper proposes a new paradigm for the analysis of long-lived security protocols. We allow entities to be active for a potentially unbounded amount of real time, provided they perform only a polynomial amount of work per unit of real time. Moreover, the space used by these entities is allocated dynamically and must be polynomially bounded. We propose a new notion of long-term implementation, which is an adaptation of computational indistinguishability to the long-lived setting. We show that long-term implementation is preserved under polynomial parallel composition and exponential sequential composition. We illustrate the use of this new paradigm by analyzing some security properties of the long-lived timestamping protocol of Haber and Kamat.