ppxscal/embedding_network huggingface dataset:
View-independent human motion classification using image-based reconstruction
Authors: R. Bodor, A. Drenner, D. Fehr, O. Masoud, N. Papanikolopoulos
Venue: Image and Vision Computing (2009)

We introduce in this paper a novel method for employing image-based rendering to extend the range of applicability of human motion and gait recognition systems. Much work has been done in the field of human motion and gait recognition, and many interesting methods for detecting and classifying motion have been developed. However, systems that can robustly recognize human behavior in real-world contexts have yet to be developed. A significant reason for this is that the activities of humans in typical settings are unconstrained in terms of the motion path. People are free to move throughout the area of interest in any direction they like. While there have been many good classification systems developed in this domain, the majority of these systems have used a single camera providing input to a training-based learning method. Methods that rely on a single camera are implicitly view-dependent. In practice, the classification accuracy of these systems often becomes increasingly poor as the angle between the camera and the direction of motion varies away from the training view angle. As a result, these methods have limited real-world applications, since it is often impossible to limit the direction of motion of people so rigidly. We demonstrate the use of image-based rendering to adapt the input to meet the needs of the classifier by automatically constructing the proper view (image), that matches the training view, from a combination of arbitrary views taken from several cameras. We tested the method on 162 sequences of video data of human motions taken indoors and outdoors, and promising results were obtained.
Modeling and simulation of a multiagent service oriented architecture for pervasive computing systems
Authors: Moeiz Miraoui, Chakib Tadj, Chokri ben Amar
Venue: Proceedings of the 2009 Workshop on Middleware for Ubiquitous and Pervasive Systems (2009)

Design and implementation of pervasive computing systems require new software tools such as architectures to support their development. In order to provide adapted services to user and applications according to the global context, devices in a pervasive computing system are context-aware. In this paper, we present the modeling and the simulation of multiagent service oriented architecture for pervasive computing system. An important step toward the validation of the architecture is made. We used colored Petri nets as modeling formalism and CPN Tools for the simulation of scenarios.
Ratio adjustment and calibration scheme for gene-wise normalization to enhance microarray inter-study prediction
Authors: Chunrong Cheng, Kui Shen, Chi Song, Jianhua Luo, George C. Tseng
Venue: Bioinformatics (2009)

Motivation: Reproducibility analyses of biologically relevant microarray studies have mostly focused on overlap of detected biomarkers or correlation of differential expression evidences across studies. For clinical utility, direct inter-study prediction (i.e. to establish a prediction model in one study and apply to another) for disease diagnosis or prognosis prediction is more important. Normalization plays a key role for such a task. Traditionally, sample-wise normalization has been a standard for inter-array and inter-study normalization. For gene-wise normalization, it has been implemented for intra-study or inter-study predictions in a few papers while its rationale, strategy and effect remain unexplored. Results: In this article, we investigate the effect of gene-wise normalization in microarray inter-study prediction. Gene-specific intensity discrepancies across studies are commonly found even after proper sample-wise normalization. We explore the rationale and necessity of gene-wise normalization. We also show that the ratio of sample sizes in normal versus diseased groups can greatly affect the performance of gene-wise normalization and an analytical method is developed to adjust for the imbalanced ratio effect. Both simulation results and applications to three lung cancer and two prostate cancer data sets, considering both binary classification and survival risk predictions, showed significant and robust improvement of the new adjustment. A calibration scheme is developed to apply the ratio-adjusted gene-wise normalization for prospective clinical trials. The number of calibration samples needed is estimated from existing studies and suggested for future applications. The result has important implication to the translational research of microarray as a practical disease diagnosis and prognosis prediction tool. Contact: ctseng@pitt.edu Availability: http://www.biostat.pitt.edu/bioinfo/ Supplementary information:Supplementary data are available at Bioinformatics online.
Power Consumption of GPUs from a Software Perspective
Authors: Sylvain Collange, David Defour, Arnaud Tisserand
Venue: Proceedings of the 9th International Conference on Computational Science: Part I (2009)

GPUs are now considered as serious challengers for high-performance computing solutions. They have power consumptions up to 300 W. This may lead to power supply and thermal dissipation problems in computing centers. In this article we investigate, using measurements, how and where modern GPUs are using energy during various computations in a CUDA environment. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Recovery study of negative bias temperature instability
Authors: Miaomiao Wang, Sufi Zafar, James H. Stathis
Venue: Microelectronic Engineering (2009)

In this work, we report a study of negative bias temperature instability (NBTI) recovery in high-k/metal-gate p-channel field effect transistors (pFETs) with different interfaces. New results on the dependence of recovery on interface, stressing voltage (V"s), stressing temperature and stressing time (t"s) are shown.
Atomic-scale theory on current-assisted thermochemical degradation mode and its field acceleration via charge trapping of O vacancy in HfSiO4
Authors: Yasushi Nakasaki, Izumi Hirano, Koichi Kato, Yuichiro Mitani
Venue: Microelectronic Engineering (2009)

An atomic-scale model for current-assisted field-accelerated thermochemical degradation via charge capturing by O vacancy (V"O) is proposed based on first-principles calculations. We found that the electron current enhances the V"O formation around the V"O itself and the hole current makes the V"O transform into the puckered structure. The calculated activation enthalpy for breakdown and the effective dipole moment agree well with the experimental values. We also found that the subordinate carriers in the generated subordinate carrier injection (GSCI) model play critical roles through a disproportion reaction of positively charged V"Os.
The pontydian performance: The performative layer
Authors: Franziska Schroeder, Pedro Rebelo
Venue: Organised Sound (2009)

In this paper we reflect on the performer–instrument relationship by turning towards the thinking practices of the French philosopher Maurice Merleau-Ponty (1908–1961). Merleau-Ponty’s phenomenological idea of the body as being at the centre of the world highlights an embodied position in the world and bestows significance onto the body as a whole, onto the body as a lived body. In order to better understand this two-way relationship of instrument and performer, we introduce the notion of the performative layer, which emerges through strategies for dealing with discontinuities, breakdowns and the unexpected in network performance.
Language-based security on Android
Authors: Avik Chaudhuri
Venue: Proceedings of the ACM SIGPLAN Fourth Workshop on Programming Languages and Analysis for Security (2009)

In this paper, we initiate a formal study of security on Android: Google's new open-source platform for mobile devices. Specifically, we present a core typed language to describe Android applications, and to reason about their data-flow security properties. Our operational semantics and type system provide some necessary foundations to help both users and developers of Android applications deal with their security concerns.
Simplex Mesh Diffusion Snakes: Integrating 2D and 3D Deformable Models and Statistical Shape Knowledge in a Variational Framework
Authors: Cristian Tejos, Pablo Irarrazaval, Arturo Cárdenas-Blanco
Venue: International Journal of Computer Vision (2009)

In volumetric medical imaging the boundaries of structures are frequently blurred due to insufficient resolution. This artefact is particularly serious in structures such as articular joints, where different cartilage surfaces appear to be linked at the contact regions. Traditional image segmentation techniques fail to separate such erroneously linked structures, and a sensible approach has been the introduction of prior-knowledge to the segmentation process. Although several 3D prior-knowledge based techniques that could successfully segment these structures have been published, most of them are pixel-labelling schemes that generate pixellated images with serious geometric distortions. The Simplex Mesh Diffusion Snakes segmentation technique presented here is an extension of the two dimensional Diffusion Snakes, but without any restriction on the number of dimensions of the data set. This technique integrates a Simplex Mesh, a region-based deformable model and Statistical Shape Knowledge into a single energy functional, so that it takes into account both the image information available directly from the data set, and the shape statistics obtained from a training process. The resulting segmentations converge correctly to well defined boundaries and provide a feasible location for those removed boundaries. The algorithm has been evaluated using 2D and 3D data sets obtained with Magnetic Resonance Imaging (MRI) and has proved to be robust to most of the MRI artefacts, providing continuous and smooth curves or surfaces with sub-pixel resolution. Additionally, this novel technique opens a wide range of opportunities for segmentation and tracking time-dependent 3D structures or data sets with more than three dimensions, due to its non-restrictive mathematical formulation.
Adding Branching to the Strand Space Model
Authors: Sibylle Fröschle
Venue: Electronic Notes in Theoretical Computer Science (ENTCS) (2009)

The strand space model is one of the most successful and widely used formalisms for analysing security protocols. This might seem surprising given that the model is not able to reflect choice points in a protocol execution: the key concept in the strand space model is that of a bundle, which models exactly one possible execution of a security protocol. Inspired by the branching processes of Petri nets, we show that branching can be introduced into the strand space model in a very natural way: bundles can be generalized to branching bundles, which are able to capture several conflicting protocol executions. Our investigations of the theory of branching bundles will motivate the concept of symbolic branching bundles, and culminate in the result that every protocol has a strand space semantics in terms of a largest symbolic branching bundle. We hope our results provide a strong theoretical basis for comparing models and providing process calculi semantics in security protocol analysis. Altogether our work is related but different to a series of works by Crazzolara and Winskel. Throughout we will profit from a close relationship of the strand space model to event structures, which has already been pointed out by these authors.
Evaluation of n-gram conflation approaches for Arabic text retrieval
Authors: Farag Ahmed, Andreas Nürnberger
Venue: Journal of the American Society for Information Science and Technology (2009)

In this paper we present a language-independent approach for conflation that does not depend on predefined rules or prior knowledge of the target language. The proposed unsupervised method is based on an enhancement of the pure n-gram model that can group related words based on various string-similarity measures, while restricting the search to specific locations of the target word by taking into account the order of n-grams. We show that the method is effective to achieve high score similarities for all word-form variations and reduces the ambiguity, i.e., obtains a higher precision and recall, compared to pure n-gram-based approaches for English, Portuguese, and Arabic. The proposed method is especially suited for conflation approaches in Arabic, since Arabic is a highly inflectional language. Therefore, we present in addition an adaptive user interface for Arabic text retrieval called &ldquo;araSearch&rdquo;. araSearch serves as a metasearch interface to existing search engines. The system is able to extend a query using the proposed conflation approach such that additional results for relevant subwords can be found automatically. &copy; 2009 Wiley Periodicals, Inc.
Note: On a problem related to the Vandermonde determinant
Authors: Tomohiro Sogabe, Moawwad El-Mikkawy
Venue: Discrete Applied Mathematics (2009)

This short note describes new properties of the elementary symmetric polynomials, and reveals that the properties give an answer to the conjecture raised by El-Mikkawy in [M.E.A. El-Mikkawy, On a connection between the Pascal, Vandermonde and Stirling matrices-II, Appl. Math. Comput. 146 (2003) 759-769].
New ensemble methods for evolving data streams
Authors: Albert Bifet, Geoff Holmes, Bernhard Pfahringer, Richard Kirkby, Ricard Gavaldà
Venue: Proceedings of the 15th ACM SIGKDD international conference on Knowledge discovery and data mining (2009)

Advanced analysis of data streams is quickly becoming a key area of data mining research as the number of applications demanding such processing increases. Online mining when such data streams evolve over time, that is when concepts drift or change completely, is becoming one of the core issues. When tackling non-stationary concepts, ensembles of classifiers have several advantages over single classifier methods: they are easy to scale and parallelize, they can adapt to change quickly by pruning under-performing parts of the ensemble, and they therefore usually also generate more accurate concept descriptions. This paper proposes a new experimental data stream framework for studying concept drift, and two new variants of Bagging: ADWIN Bagging and Adaptive-Size Hoeffding Tree (ASHT) Bagging. Using the new experimental framework, an evaluation study on synthetic and real-world datasets comprising up to ten million examples shows that the new ensemble methods perform very well compared to several known methods.
The adaptive immersed interface finite element method for elliptic and Maxwell interface problems
Authors: Zhiming Chen, Yuanming Xiao, Linbo Zhang
Venue: Journal of Computational Physics (2009)

We propose self-adaptive finite element methods with error control for solving elliptic and electromagnetic problems with discontinuous coefficients. The meshes in the methods do not need to fit the interfaces. New error indicators are introduced to control the error due to non-body-fitted meshes. Flexible h-adaptive strategies are developed, which can be systematically extended to a large class of interface problems. Extensive numerical experiments are performed to support the theoretical results and to show the competitive behavior of the adaptive algorithm even for interfaces involving corner or tip singularities.
Selection of optimal supplier in supply chain management strategy with analytic network process and choquet integral
Authors: Ming-Lang Tseng, Jui Hsiang Chiang, Lawrence W. Lan
Venue: Computers and Industrial Engineering (2009)

Selection of appropriate suppliers in supply chain management strategy (SCMS) is a challenging issue because it requires battery of evaluation criteria/attributes, which are characterized with complexity, elusiveness, and uncertainty in nature. This paper proposes a novel hierarchical evaluation framework to assist the expert group to select the optimal supplier in SCMS. The rationales for the evaluation framework are based upon (i) multi-criteria decision making (MCDM) analysis that can select the most appropriate alternative from a finite set of alternatives with reference to multiple conflicting criteria, (ii) analytic network process (ANP) technique that can simultaneously take into account the relationships of feedback and dependence of criteria, and (iii) choquet integral-a non-additive fuzzy integral that can eliminate the interactivity of expert subjective judgment problems. A case PCB manufacturing firm is studied and the results indicated that the proposed evaluation framework is simple and reasonable to identify the primary criteria influencing the SCMS, and it is effective to determine the optimal supplier even with the interactive and interdependent criteria/attributes. This hierarchical evaluation framework provides a complete picture in SCMS contexts to both researchers and practitioners.
Discovering Missing Background Knowledge in Ontology Matching
Authors: Fausto Giunchiglia, Pavel Shvaiko, Mikalai Yatskevich
Venue: Proceeding of the 2006 conference on ECAI 2006: 17th European Conference on Artificial Intelligence August 29 -- September 1, 2006, Riva del Garda, Italy (2006)

Semantic matching determines the mappings between the nodes of two graphs (e.g., ontologies) by computing logical relations (e.g., subsumption) holding among the nodes that correspond semantically to each other. We present an approach to deal with the lack of background knowledge in matching tasks by using semantic matching iteratively. Unlike previous approaches, where the missing axioms are manually declared before the matching starts, we propose a fully automated solution. The benefits of our approach are: (i) saving some of the pre-match efforts, (ii) improving the quality of match via iterations, and (iii) enabling the future reuse of the newly discovered knowledge. We evaluate the implemented system on large real-world test cases, thus, proving empirically the benefits of our approach.
Seven pitfalls to avoid when running controlled experiments on the web
Authors: Thomas Crook, Brian Frasca, Ron Kohavi, Roger Longbotham
Venue: Proceedings of the 15th ACM SIGKDD international conference on Knowledge discovery and data mining (2009)

Controlled experiments, also called randomized experiments and A/B tests, have had a profound influence on multiple fields, including medicine, agriculture, manufacturing, and advertising. While the theoretical aspects of offline controlled experiments have been well studied and documented, the practical aspects of running them in online settings, such as web sites and services, are still being developed. As the usage of controlled experiments grows in these online settings, it is becoming more important to understand the opportunities and pitfalls one might face when using them in practice. A survey of online controlled experiments and lessons learned were previously documented in Controlled Experiments on the Web: Survey and Practical Guide (Kohavi, et al., 2009). In this follow-on paper, we focus on pitfalls we have seen after running numerous experiments at Microsoft. The pitfalls include a wide range of topics, such as assuming that common statistical formulas used to calculate standard deviation and statistical power can be applied and ignoring robots in analysis (a problem unique to online settings). Online experiments allow for techniques like gradual ramp-up of treatments to avoid the possibility of exposing many customers to a bad (e.g., buggy) Treatment. With that ability, we discovered that it's easy to incorrectly identify the winning Treatment because of Simpson's paradox.
Piezoelectric actuator for a force-feedback application: Preliminary evaluation
Authors: G. M'Boungui, B. Lemaire-Semail, F. Giraud
Venue: Proceedings of the World Haptics 2009 - Third Joint EuroHaptics conference and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems (2009)

As a solution to the lack of compactness and simplicity often encountered in haptic interfaces, we propose a device based on friction coefficient control principle. This device includes polarised piezoceramics well adjusted and glued to a 64x38x3 mm copper-beryllium plate supported by four legs. Then, properly energised around a resonant frequency, with legs at antinodes, a stationary wave is created in the plate. Variable friction forces between the legs and the plane substrate are created by the control of the wave amplitude, according to electro-active lubrication. So the user obtains force feedback by holding the plate, and moving it on a plane substrate, as he could do with a mouse interface. Preliminary psychophysical evaluation trends to assess the validity of the device as a force feedback interface.
Supporting of legal reasoning for cases which are not strictly regulated by law
Authors: Tomasz Zurek, Emil Kruk
Venue: Proceedings of the 12th International Conference on Artificial Intelligence and Law (2009)

Statute law legislators are usually not in a position to foresee each and every situation or event which may actually occur in real life. That is why lawyers in the course of their everyday practice very often struggle with interpreting the cases which are not expressly regulated in the law. The legal theory and practice has given rise to a wide array of methods to deal with this type of problems. The solutions described in this article have been implemented in the advisory system developed by the authors whose main goal is to provide automatic legal advice on the Agricultural Tax
Automated Sealed-Bid Negotiation Model for Multi-issue Based on Fuzzy Method
Authors: Linlan Zhang, Haigang Song, Xueguang Chen
Venue: Proceedings of the 6th International Symposium on Neural Networks: Advances in Neural Networks - Part II (2009)

This paper presents an automated sealed-bid design for multi-issue negotiation. In our negotiation model, both agents simultaneously submit their offers to the mediate agent. Each agent has a representation of its desired attributes for a trading commodity using fuzzy linguistic terms. This method is flexible for the agents to offer according to own demand, taking into account the interdependencies between the attributes. It is important to emphasize that proposed bargaining method is carried out under incomplete information, and agents' information about own parameters are considered completely private. The design can discourage counter-speculation and effectively control fraud and misrepresentation in a certain extent. In addition, using the proposed method of calculating agreed-price, agents can be stimulated to reach an agreement as early as possible. Through a case study, the capabilities of the proposed method are illustrated.
Static Models of Derivative-Coordinates Phase Spaces for Multivariate Time Series Classification: An Application to Signature Verification
Authors: Jonas Richiardi, Krzysztof Kryszczuk, Andrzej Drygajlo
Venue: Proceedings of the Third International Conference on Advances in Biometrics (2009)

Multivariate time series are sequences, whose order is provided by a time index; thus, most classifiers used on such data treat time as a special quantity, and encode it structurally in a model. A typical example of such models is the hidden Markov model, where time is explicitely used to drive state transitions. The time information is discretised into a finite set of states, the cardinality of which is largely chosen by empirical criteria. Taking as an example task signature verification, we propose an alternative approach using static probabilistic models of phase spaces, where the time information is preserved by embedding of the multivariate time series into a higher-dimensional subspace, and modelled probabilistically by using the theoretical framework of static Bayesian networks. We show empirically that performance is equivalent to state-of-the-art signature verification systems.