ppxscal/embedding_network huggingface dataset:
A hybrid approach to item recommendation in folksonomies
Authors: Robert Wetzker, Winfried Umbrath, Alan Said
Venue: Proceedings of the WSDM '09 Workshop on Exploiting Semantic Annotations in Information Retrieval (2009)

In this paper we consider the problem of item recommendation in collaborative tagging communities, so called folksonomies, where users annotate interesting items with tags. Rather than following a collaborative filtering or annotation-based approach to recommendation, we extend the probabilistic latent semantic analysis (PLSA) approach and present a unified recommendation model which evolves from item user and item tag co-occurrences in parallel. The inclusion of tags reduces known collaborative filtering problems related to overfitting and allows for higher quality recommendations. Experimental results on a large snapshot of the delicious bookmarking service show the scalability of our approach and an improved recommendation quality compared to two-mode collaborative or annotation based methods.
Autonomous vs. tele-operated: how people perceive human-robot collaboration with hrp-2
Authors: Astrid Weiss, Daniela Wurhofer, Michael Lankes, Manfred Tscheligi
Venue: Proceedings of the 4th ACM/IEEE international conference on Human robot interaction (2009)

Effective collaboration between robots and humans is not only a question of interface design and usability, but also of user experience and social acceptance. To investigate these aspects for Human-Robot Collaboration with the HRP-2 robot, two video-based focus groups enhanced with creative stimuli were conducted. The following research question was addressed: Is the HRP-2 robot perceived differently in an autonomous collaboration condition compared to a tele-operated collaboration condition, in terms of social acceptance and user experience?"The results show that participants in general are open to a humanoid robot as working partner as long as there is a clear distinction between a human and a robot, in terms of tasks and working procedures. Furthermore, participants stated a positive attitude toward the remotely-controlled HRP-2 robot.
Models and Simulations for Portfolio Rebalancing
Authors: Gianfranco Guastaroba, Renata Mansini, M. Grazia Speranza
Venue: Computational Economics (2009)

In 1950 Markowitz first formalized the portfolio optimization problem in terms of mean return and variance. Since then, the mean-variance model has played a crucial role in single-period portfolio optimization theory and practice. In this paper we study the optimal portfolio selection problem in a multi-period framework, by considering fixed and proportional transaction costs and evaluating how much they affect a re-investment strategy. Specifically, we modify the single-period portfolio optimization model, based on the Conditional Value at Risk (CVaR) as measure of risk, to introduce portfolio rebalancing. The aim is to provide investors and financial institutions with an effective tool to better exploit new information made available by the market. We then suggest a procedure to use the proposed optimization model in a multi-period framework. Extensive computational results based on different historical data sets from German Stock Exchange Market (XETRA) are presented.
Present and Future of Practical SAT Solving
Authors: Oliver Kullmann
Venue: Complexity of Constraints: An Overview of Current Research Themes (2008)

We review current SAT solving, concentrating on the two paradigms of conflict-driven and look-ahead solvers, and with a view towards the unification of these two paradigms. A general "modern" scheme for DPLL algorithms is presented, which allows natural representations for "modern" solvers of these two types.
Bipartite modular multiplication with twice the bit-length of multipliers
Authors: Masayuki Yoshino, Katsuyuki Okeya, Camille Vuillaume
Venue: International Journal of Information Security (2009)

This paper presents a new technique to compute 2&#x2113;-bit bipartite multiplications with &#x2113;-bit bipartite multiplication units. Low-end devices such as smartcards are usually equipped with crypto-coprocessors for accelerating the heavy computation of modular multiplications; however, security standards such as NIST and EMV have declared extending the bit length of RSA cryptosystem to resist mathematical attacks, making the multiplier quickly outdated. Therefore, the double-size techniques have been studied this decade to extend the life expectancy of such multipliers. This paper proposes new double-size techniques based on the multipliers implementing either classical or Montgomery modular multiplications, or even both simultaneously (bipartite modular multiplication), in which case one can potentially compute modular multiplications twice faster. Furthermore, in order to get a more realistic estimation than the other works, this paper considers not only the cost of the multiplication, but also the cost of the other arithmetic instructions. In our estimation, the proposal provides comparable results for classical multiplier and Montgomery multiplier, and is the only available method for the bipartite multiplier.
Coloring Geometric Range Spaces
Authors: Greg Aloupis, Jean Cardinal, S&#x00e9;bastien Collette, Stefan Langerman, Shakhar Smorodinsky
Venue: Discrete Computational Geometry (2009)

We study several coloring problems for geometric range-spaces. In addition to their theoretical interest, some of these problems arise in sensor networks. Given a set of points in &#x211d;2 or &#x211d;3, we want to color them so that every region of a certain family (e.g.,&#x00a0;every disk containing at least a certain number of points) contains points of many (say, k) different colors. In this paper, we think of the number of colors and the number of points as functions of k. Obviously, for a fixed k using k colors, it is not always possible to ensure that every region containing k points has all colors present. Thus, we introduce two types of relaxations: either we allow the number of colors used to increase to c(k), or we require that the number of points in each region increases to p(k). Symmetrically, given a finite set of regions in &#x211d;2 or &#x211d;3, we want to color them so that every point covered by a sufficiently large number of regions is contained in regions of k different colors. This requires the number of covering regions or the number of allowed colors to be greater than k. The goal of this paper is to bound these two functions for several types of region families, such as halfplanes, halfspaces, disks, and pseudo-disks. This is related to previous results of Pach, Tardos, and T&#x00f3;th on decompositions of coverings.
Minimizing point-to-point transmission energy with error correction coding and transmission power control
Authors: Junjun Gu, Gang Qu, Aihong Yao, Ahmed Bouridane
Venue: Proceedings of the 2008 International Conference on Advanced Infocomm Technology (2008)

Energy efficiency has become an important concern for the design of communication systems, particularly the wireless sensor networks where recharging battery might not be feasible. In this paper, we investigate how error correction coding (ECC) and transmission power level can impact the packet loss rate and transmission energy. We focus our analysis on the direct point-to-point communication, which is the basic unit for any data communication, in three popular scenarios: only one re-transmission is allowed; multiple re-transmissions are made to guarantee a given packet loss rate; and re-transmitting until the packet is received correctly. For each case, we derive formulas to show whether and when ECC and power control should be used. We then propose a 2-phase approach that uses ECC and power control simultaneously to reduce energy while maintaining the required packet loss rate. Numerical simulation validates our claims and indicates that the proposed 2-phase approach can reduce transmission energy significantly.
A Definition of Cellular Interface Problems
Authors: Markus Kirkilionis, Mirela Domijan, Martin Eigel, Erwin George, Mike Li, Luca Sbano
Venue: Membrane Computing: 9th International Workshop, WMC 2008, Edinburgh, UK, July 28-31, 2008, Revised Selected and Invited Papers (2009)

We define a class of cellular interface problems (short: CIP) that mathematically model the exchange of molecules in a compartmentalised living cell. Defining and eventually solving such compartmental problems is important for several reasons. They are needed to understand the organisation of life itself, for example by exploring different 'origin of life' hypothesis based on simple metabolic pathways and their necessary division into one or more compartments. In more complex forms investigating cellular interface problems is a way to understand cellular homeostasis of different types, for example ionic fluxes and their composition between all different cellular compartments. Understanding homeostasis and its collapse is important for many physiological medical applications. This class of models is also necessary to formulate efficiently and in detail complex signalling processes taking place in different cell types, with eukaryotic cells the most complex ones in terms of sophisticated compartmentalisation. We will compare such mathematical models of signalling pathways with rule-based models as formulated in membrane computing in a final discussion. The latter is a theory that investigates computer programmes with the help of biological concepts, like a subroutine exchanging data with the environment, in this case a programme with its global variables.
Three-Way Pinpointing of Emergency Call from RFID-Reader-Equipped Cellular Phone
Authors: Osamu Takizawa, Masafumi Hosokawa, Ken'Ichi Takanashi, Yasushi Hada, Akihiro Shibayama, Byeong-Pyo Jeong
Venue: Mobile Response: Second International Workshop on Mobile Information Technology for Emergency Response, MobileResponse 2008. Bonn, Germany, May 29-30, 2008, Revised Selected Papers (2009)

The ability to accurately pinpoint the point of origin of an emergency call can greatly increase response times of emergency services. Emergency calls made from cellular phones can only be traced by the Global Positioning System (GPS) or cell-based positioning, which are sometimes unacceptably inaccurate; they cannot provide information on, e.g. the exact floor of a building and also suffer from blind spots. We have been developing a system that can determine the location of a cellular phone using in-built passive or active radio-frequency identification (RFID) readers and GPS receivers. This paper introduces the outline of the prototype system.
The triple-watermarking algorithm with multiple description coding over lossy communication networks
Authors: Shu-Chuan Chu, Lakhmi C. Jain, Hsiang-Cheh Huang, Jeng-Shyang Pan
Venue: Proceedings of the 3rd International Conference on Ubiquitous Information Management and Communication (2009)

Watermarking is one useful solution for digital rights management (DRM) systems. In this paper, in addition to following conventional objectives to conquer against intentional or unintentional attacks, we not only watch the survivability of embedded watermark, but also focus on retaining the watermarked image quality with the aid of multiple description coding (MDC). MDC is an algorithm for error resilient coding, suitable for transmitting compressed data over multiple channels. In this paper, we propose an innovative algorithm on vector quantization (VQ) based image watermarking, which is suitable for error-resilient transmission over noisy channels. By incorporating watermarking with multiple description coding, the scheme we proposed for embedding three watermarks can effectively overcome channel impairments while retaining the capability for copyright and ownership protection. With the promising simulation results presented, we can demonstrate the utility and practicability of our algorithm.
Cognitive agents - a procedural perspective relying on the predictability of Object-Action-Complexes (OACs)
Authors: F. Wörgötter, A. Agostini, N. Krüger, N. Shylo, B. Porr
Venue: Robotics and Autonomous Systems (2009)

Embodied cognition suggests that complex cognitive traits can only arise when agents have a body situated in the world. The aspects of embodiment and situatedness are being discussed here from the perspective of linear systems theory. This perspective treats bodies as dynamic, temporally variable entities, which can be extended (or curtailed) at their boundaries. We show how acting agents can, for example, actively extend their body for some time by incorporating predictably behaving parts of the world and how this affects the transfer functions. We suggest that primates have mastered this to a large degree increasingly splitting their world into predictable and unpredictable entities. We argue that temporary body extension may have been instrumental in paving the way for the development of higher cognitive complexity as it is reliably widening the cause-effect horizon about the actions of the agent. A first robot experiment is sketched to support these ideas. We continue discussing the concept of Object-Action Complexes (OACs) introduced by the European PACO-PLUS consortium to emphasize the notion that, for a cognitive agent, objects and actions are inseparably intertwined. In another robot experiment we devise a semi-supervised procedure using the OAC-concept to demonstrate how an agent can acquire knowledge about its world. Here the notion of predicting changes fundamentally underlies the implemented procedure and we try to show how this concept can be used to improve the robot's inner model and behaviour. Hence, in this article we have tried to show how predictability can be used to augment the agent's body and to acquire knowledge about the external world, possibly leading to more advanced cognitive traits.
Effect of thermal pole tip protrusion and disk roughness on slider disk contacts
Authors: Jianfeng Xu, James D. Kiely, Yiao-Tee Hsia, Frank E. Talke
Venue: Microsystem Technologies (2009)

Ultra-high areal density for hard disk drives requires a stable head disk interface at a flying height lower than 8&#x00a0;nm. At such a low flying height, small flying height variations may cause slider/disk contacts. Slider/disk contacts can also occur when a write-current is applied to the write coil since the flying height between slider and disk can be affected by the thermal expansion of the pole tip. In this paper, we investigate the vibration characteristics of sliders during thermally induced contacts using laser Doppler vibrometry. We perform a parametric study of contact events using disks with different surface roughness and lubricant thicknesses, and analyze the slider motion statistically. For a given write current, we observe that the slider vibrations increase with disk roughness and lubricant thickness.
An ontological Proxy Agent with prediction, CBR, and RBR techniques for fast query processing
Authors: Sheng-Yuan Yang, Chun-Liang Hsu
Venue: Expert Systems with Applications: An International Journal (2009)

This paper proposed a three-tier Proxy Agent working as a mediator between the users and the backend process of a FAQ system. The first tier makes use of an improved sequential patterns mining technique to propose effective query prediction and cache services. The second tier employs an ontology-supported case-based reasoning technique to propose adapted query solutions and tune itself by retaining and updating highly-satisfied cases identified by the user. Finally, the third tier utilizes an ontology-supported rule-based reasoning to generate possible solutions for the user. Our experiments show around 79.1% of the user queries can be answered by Proxy Agent, leaving about 20.9% of the queries for the backend Answerer Agent to take care, which can effectively alleviate the overloading problem usually associated with a backend server.
Some statistics for Fibonacci tableaux
Authors: Kendra Killpatrick
Venue: European Journal of Combinatorics (2009)

Permutation statistics and their connections to Young tableaux have played an important role in enumerative combinatorics. Fibonacci tableaux were defined in 1975 by Stanley, but very few statistics have been defined for these tableaux. In this paper we give definitions for several statistics on Fibonacci tableaux and make connections between these statistics and known statistics for permutations. These connections allow for equidistribution results to be given on the set of standard Fibonacci tableaux.
On the Security of an MPEG-Video Encryption Scheme Based on Secret Huffman Tables
Authors: Shujun Li, Guanrong Chen, Albert Cheung, Kwok-Tung Lo, Mohan Kankanhalli
Venue: Proceedings of the 3rd Pacific Rim Symposium on Advances in Image and Video Technology (2009)

This paper re-studies the security of an MPEG-video encryption scheme based on secret Huffman tables. The present cryptanalysis shows that: 1) the key space of the encryption scheme is not sufficiently large against divide-and-conquer (DAC) ciphertext-only attack; 2) its security against the chosen-plaintext attack is very weak. The insecurity is mainly due to the separated use of different Huffman tables for different sets of syntax elements. A brief discussion on how to improve this MPEG-video encryption scheme is also given.
Color Demosaicing Using Asymmetric Directional Interpolation and Hue Vector Smoothing
Authors: Yoshihisa Takahashi, Kentaro Hiraki, Hisakazu Kikuchi, Shogo Muramatsu
Venue: IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences (2008)

This paper presents a color demosaicing method applied to the Bayer pattern color filter array (CFA). Reliable estimation of an edge direction, edge-directed asymmetric interpolation, and the use of color samples at immediate neighbors are considered as the key guidelines for smooth and sharp image restoration. Also, special interest is directed to local areas that are rich in high spatial frequency variations. For suppression of false colors likely to occur in those areas, a hue vector representation is introduced so that the spatial correlation between different color components may be exploited in consistent with the local constant-hue principle. Smoothing is repeated in the hue vector field a few times. Experimental results have shown preferable performances in terms of PSNR, CIELAB color difference, hue angle difference, CIE chromaticity and visual appearance, in particular resulting in less false colors.
Analysis and Improvement of an Anonymity Scheme for P2P Reputation Systems
Authors: Li-ming Hao, Song-nian Lu, Shu-tang Yang, Ning Liu, Qi-shan Huang
Venue: IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences (2008)

In 2006, Miranda et al. proposed an anonymity scheme to achieve peers' anonymity in Peer-to-Peer (P2P) reputation systems. In this paper, we show that this scheme can not achieve peers' anonymity in two cases. We also propose an improvement which solves the problem and improves the degree of anonymity.
First-aid: surviving and preventing memory management bugs during production runs
Authors: Qi Gao, Wenbin Zhang, Yan Tang, Feng Qin
Venue: Proceedings of the 4th ACM European conference on Computer systems (2009)

Memory bugs in C/C++ programs severely affect system availability and security. This paper presents First-Aid, a lightweight runtime system that survives software failures caused by common memory management bugs and prevents future failures by the same bugs during production runs. Upon a failure, First-Aid diagnoses the bug type and identifies the memory objects that trigger the bug. To do so, it rolls back the programto previous checkpoints and uses two types of environmental changes that can prevent or expose memory bug manifestation during re-execution. Based on the diagnosis, First-Aid generates and applies runtime patches to avoid the memory bug and prevent its reoccurrence. Furthermore, First-Aid validates the consistent effects of the runtime patches and generates on-site diagnostic reports to assist developers in fixing the bugs. We have implemented First-Aid on Linux and evaluated it with seven applications that contain various types of memory bugs, including buffer overflow, uninitialized read, dangling pointer read/write, and double free. The results show that First-Aid can quickly diagnose the tested bugs and recover applications from failures (in 0.084 to 3.978 seconds). The results also show that the runtime patches generated by First-Aid can prevent future failures caused by the diagnosed bugs. Additionally, First-Aid provides detailed diagnostic information on both the root cause and the manifestation of the bugs. Furthermore, First-Aid incurs low overhead (0.4-11.6% with an average of 3.7%) during normal execution for the tested buggy applications, SPEC INT2000, and four allocation intensive programs.
Active Vibration Control for Smart Structure Base on the Fuzzy Logic
Authors: Zhang Jing-jun, Cao Li-ya, Yuan Wei-ze
Venue: Proceedings of the 2009 International Conference on Advanced Computer Control (2009)

In the study of active vibration of piezoelectric smart structures, the piezoelectric materials always show non-liner characteristic, so this paper uses the fuzzy logic to control the smart structures vibration. The fuzzy IF-THEN rules are established on analysis of the motion traits of cantilever beam. The fuzzy controller designs on using the displacement and the velocity of the cantilever beams tips as the inputs, the control force on cantilever beams as the output. This new method improves calculation efficiency and reduces calculation complexity, and the better effects than which uses the acceleration and its rate of the cantilever beams tips as the inputs. The simulation results with Matlab illustrate that the proposed method has a better control performance than existing methods.
Bayesian Mixture of AR Models for Time Series Clustering
Authors: Venkataramana Kini B, C. Chandra Sekhar
Venue: Proceedings of the 2009 Seventh International Conference on Advances in Pattern Recognition (2009)

In this paper we propose a Bayesian framework for estimation of parameters of a mixture of autoregressive model, for time series clustering. The proposed approach is based on variational principles and provides a tractable approximation to the true posterior density that minimizes Kullback-Liebler(KL) divergence w.r.t prior distribution. The proposed approach is applied both on simulated and real time series data sets and found to be useful in exploring and finding the true number of underlying clusters, starting from arbitrarily large number clusters.
Morphological Elastic Graph Matching Applied to Frontal Face Authentication Under Optimal and Real Conditions
Authors: C. Kotropoulos, A. Tefas, I. Pitas
Venue: Proceedings of the 1999 IEEE International Conference on Multimedia Computing and Systems - Volume 02 (1999)

In this paper, morphological elastic graph matching is applied to frontal face authentication on databases collected either under optimal conditions or during real-world tests (i.e., access-control to buildings or tele-services via INTERNET in a typical office environment etc.). It is demonstrated that the morphological elastic graph matching achieves a very low equal error rate on databases collected under optimal conditions. However, its performance deteriorates in real-world experiments. The compensation for variable recording conditions, such as changes in illumination, scale differences and varying face position prior to the application of morphological elastic matching is proposed. The results obtained indicate that the proposed approach overcomes the image variations and stabilizes the performance of the authentication algorithm.