ppxscal/embedding_network huggingface dataset:
Feature Selection for Unsupervised and Supervised Inference: The Emergence of Sparsity in a Weight-Based Approach
Authors: Lior Wolf, Amnon Shashua
Venue: The Journal of Machine Learning Research (2005)

The problem of selecting a subset of relevant features in a potentially overwhelming quantity of data is classic and found in many branches of science. Examples in computer vision, text processing and more recently bio-informatics are abundant. In text classification tasks, for example, it is not uncommon to have 104 to 107 features of the size of the vocabulary containing word frequency counts, with the expectation that only a small fraction of them are relevant. Typical examples include the automatic sorting of URLs into a web directory and the detection of spam email.In this work we present a definition of "relevancy" based on spectral properties of the Laplacian of the features' measurement matrix. The feature selection process is then based on a continuous ranking of the features defined by a least-squares optimization process. A remarkable property of the feature relevance function is that sparse solutions for the ranking values naturally emerge as a result of a "biased non-negativity" of a key matrix in the process. As a result, a simple least-squares optimization process converges onto a sparse solution, i.e., a selection of a subset of features which form a local maximum over the relevance function. The feature selection algorithm can be embedded in both unsupervised and supervised inference problems and empirical evidence show that the feature selections typically achieve high accuracy even when only a small fraction of the features are relevant.
Better control on recommender systems
Authors: Esma Aimeur, Flavien Serge Mani Onana
Venue: Proceedings of the The 8th IEEE International Conference on E-Commerce Technology and The 3rd IEEE International Conference on Enterprise Computing, E-Commerce, and E-Services (2006)

In the context of electronic commerce, recommender systems enable merchants to assist customers in finding available products that will best satisfy their need. However, a recommender system usually operates as a kind of black box from which customers receive recommendations for products. Of particular interest are recommender systems based on Collaborative Filtering, in which customers provide the recommender system with ratings on products and receive recommendations based on the similarity paradigm. In this paper, we introduce an approach in which customers self-control the collaborative filtering process. More precisely, our approach uses a list of contacts, which allows a better control on the recommendations provided locally (using the list of contacts), while still being able to access and even influence the global recommendations of the system (using the whole database of customers). We believe that our system allows more confidence in the customer because it enables him to maintain real-time statistics on his similarity with customers forming his ring of contacts.
Globally distributed software development and pair programming
Authors: Nick V. Flor
Venue: Communications of the ACM (2006)

The benefits of pair programming are unquestioned provided the pairs work in close proximity. Globally distributed software development creates opportunities for remote pair programming. What must be done to yield the same benefits?
Information Model for Quality Management Methods in e-Learning
Authors: Kenji Hirata
Venue: Proceedings of the Sixth IEEE International Conference on Advanced Learning Technologies (2006)

Quality in e-Learning has been focusing on. ISO/IEC 19796-1, which deals with the issue of quality management and assurance in e-Learning, was just published in 2005 as an international standard. This standard indicates the process that produces e- Learning. But it is indispensable to make clear quality concept and object in order to understand the quality approaches and to use its standard. Measurement method is useful to indicate contents of quality which should be assured. So this paper suggested a information model for quality methods.
Adaptive Localized QoS-Constrained Data Aggregation and Processing in Distributed Sensor Networks
Authors: Jin Zhu, Symeon Papavassiliou, Jie Yang
Venue: IEEE Transactions on Parallel and Distributed Systems (2006)

In this paper, an efficient Quality of Service (QoS)-constrained data aggregation and processing approach for distributed wireless sensor networks is investigated and analyzed. One of the key features of the proposed approach is that the task QoS requirements are taken into account to determine when and where to perform the aggregation in a distributed fashion, based on the availability of local only information. Data aggregation is performed on the fly at intermediate sensor nodes, while at the same time the end-to-end latency constraints are satisfied. Furthermore, a localized adaptive data collection algorithm performed at the source nodes is developed that balances the design tradeoffs of delay, measurement accuracy, and buffer overflow, for given QoS requirements. The performance of the proposed approach is analyzed and evaluated, through modeling and simulation, under different data aggregation scenarios and traffic loads. The impact of several design parameters and tradeoffs on various critical network and application related performance metrics, such as energy efficiency, network lifetime, end-to-end latency, and data loss are also evaluated and discussed.
Distributed versus face-to-face meetings for architecture evalution: a controlled experiment
Authors: Muhammad Ali Babar, Barbara Kitchenham, Ross Jeffery
Venue: Proceedings of the 2006 ACM/IEEE international symposium on Empirical software engineering (2006)

Scenario-based methods for evaluating software architecture require a large number of stakeholders to be collocated for evaluation sessions. Collocating stakeholders is often an expensive exercise. To reduce expense, we have proposed a framework for supporting software architecture evaluation process using groupware systems. This paper presents a controlled experiment that we conducted to assess the effectiveness of scenario profile construction using distributed meetings. We used a cross-over experiment involving 32 teams of three 3rd and 4th year undergraduate students. We found that the quality of scenarios produced by distributed teams using a groupware tool were significantly better than the quality of scenarios produced by face-to-face teams (p<0.001). However, questionnaires indicated that most participants preferred the face-toface arrangement (82%) and 60% thought the distributed meetings were less efficient. We conclude that distributed meetings are extremely effective but that tool support must be of a high standard or participants will not find distributed meetings acceptable.
Computational Grids for Mid-Sized Collaborative Projects: The eMinerals Experience
Authors: M. T. Dove, T. O. H. White, A. M. Walker, R. P. Bruin, K. F. Austen, E. Artacho, L. A. Sullivan, M. Calleja, M. G. Tucker, R. P. Tyer, P. A. Couch, K. Kleese van Dam, R. J. Allan, I. T. Todorov, C. Chapman, W. Emmerich, A. Marmier, S. C. Parker, M. O. Blanchard, C. R. A. Catlow, Z. Du, N. de Leeuw, G. J. Lewis, V. Alexandrov, M. Alfredsson, J. P. Brodholt, P. Murray-Rust
Venue: Proceedings of the Second IEEE International Conference on e-Science and Grid Computing (2006)

Grid computing has the potential to revolutionise how small groups of simulation scientists work together to tackle new science problems. In this paper we report how the eMinerals project has developed a small scale integrated compute and data grid infrastructure - the eMinerals minigrid - and developed generic job submission tools that exploit this infrastructure and which enable the science users to also access other grid systems.
Ontology-Based Content Management and Access Framework for Supporting E-Learning Systems
Authors: Ming Mao, Yefei Peng, Daqing He
Venue: Proceedings of the 2006 IEEE/WIC/ACM international conference on Web Intelligence and Intelligent Agent Technology (2006)

E-Learning is a fast, just-in-time, and non-linear learning process, which is now widely applied in distributed and dynamic environments such as on the World Wide Web. However, it also poses three challenges to the systems that support e-learning. This paper present our on-going effort to develop an ontology-based framework for e-learning systems, which allows teachers to organize learning materials in a dynamic and flexible manner, and provides multiple ways for students to access the materials either by navigation, search or recommendation. A module that helps to classify the learning materials according to the schema of the ontology is also presented in the proposed framework.
fMRI Responses to Video and Point-Light Displays of Moving Humans and Manipulable Objects
Authors: Michael S. Beauchamp, Kathryn E. Lee, James V. Haxby, Alex Martin
Venue: Journal of Cognitive Neuroscience (2003)

We used fMRI to study the organization of brain responses to different types of complex visual motion. In a rapid event-related design, subjects viewed video clips of humans performing different whole-body motions, video clips of manmade manipulable objects (tools) moving with their characteristic natural motion, point-light displays of human whole-body motion, and point-light displays of manipulable objects.The lateral temporal cortex showed strong responses to both moving videos and moving point-light displays, supporting the hypothesis that the lateral temporal cortex is the cortical locus for processing complex visual motion. Within the lateral temporal cortex, we observed segregated responses to different types of motion. The superior temporal sulcus (STS) responded strongly to human videos and human point-light displays, while the middle temporal gyrus (MTG) and the inferior temporal sulcus responded strongly to tool videos and tool point-light displays.In the ventral temporal cortex, the lateral fusiform responded more to human videos than to any other stimulus category while the medial fusiform preferred tool videos. The relatively weak responses observed to point-light displays in the ventral temporal cortex suggests that form, color, and texture (present in video but not point-light displays) are the main contributors to ventral temporal activity. In contrast, in the lateral temporal cortex, the MTG responded as strongly to point-light displays as to videos, suggesting that motion is the key determinant of response in the MTG. Whereas the STS responded strongly to point-light displays, it showed an even larger response to video displays, suggesting that the STS integrates form, color, and motion information.
Random Measurement Bases, Quantum State Distinction and Applications to the Hidden Subgroup Problem
Authors: Pranab Sen
Venue: Proceedings of the 21st Annual IEEE Conference on Computational Complexity (2006)

We show that measuring any two low rank quantum states in a random orthonormal basis gives, with high probability, two probability distributions having total variation distance at least a universal constant times the Frobenius distance between the two states. This implies that for any finite ensemble of quantum states there is a single POVM that distinguishes between every pair of states from the ensemble by at least a constant times their Frobenius distance; in fact, with high probability a random POVM, under a suitable definition of randomness, suffices. There are examples of ensembles with constant pairwise trace distance where a single POVM cannot distinguish pairs of states by much better than their Frobenius distance, including the important ensemble of coset states of hidden subgroups of the symmetric group [MRS05]. We next consider the random Fourier method for the hidden subgroup problem (HSP) which consists of Fourier sampling the coset state of the hidden subgroup using random orthonormal bases for the group representations. In cases where every representation of the group has polynomially bounded rank when averaged over the hidden subgroup, the random Fourier method gives a POVM for the HSP operating on one coset state at a time and using totally a polynomial number of coset states. In particular, we get such POVMs whenever the group and the hidden subgroup form a Gel'fand pair, e. g., abelian, dihedral and Heisenberg groups. This gives a positive counterpart to earlier negative results about random Fourier sampling when the above rank is exponentially large [GSVV04], which happens for example in the HSP in the symmetric group. The drawback of random POVMs is that they are not efficient to implement, since measuring in a random basis takes exponential time as can be seen by a counting argument. This leads us to the open question of efficiently implementable pseudo-random measurement bases.
Iterative rounding 2-approximation algorithms for minimum-cost vertex connectivity problems
Authors: Lisa Fleischer, Kamal Jain, David P. Williamson
Venue: Journal of Computer and System Sciences (2006)

The survivable network design problem (SNDP) is the following problem: given an undirected graph and values rij for each pair of vertices i and j, find a minimum-cost subgraph such that there are at least rij disjoint paths between vertices i and j. In the edge connected version of this problem (EC-SNDP), these paths must be edge-disjoint. In the vertex connected version of the problem (VC-SNDP), the paths must be vertex disjoint. The element connectivity problem (ELC-SNDP, or ELC) is a problem of intermediate difficulty. In this problem, the set of vertices is partitioned into terminals and nonterminals. The edges and nonterminals of the graph are called elements. The values rij are only specified for pairs of terminals i, j, and the paths from i to j must be element disjoint. Thus if rij-1 elements fail, terminals i and j are still connected by a path in the network.These variants of SNDP are all known to be NP-hard. The best known approximation algorithm for the EC-SNDP has performance guarantee of 2 and iteratively rounds solutions to a linear programming relaxation of the problem. ELC has a primal-dual O(log k)-approximation algorithm, where k = maxi,j rij. Since this work first appeared as an extended abstract, it has been shown that it is hard to approximate VC-SNDP to factor 2log1-εn.In this paper we investigate applying iterative rounding to ELC and VC-SNDP We show that iterative rounding will not yield a constant factor approximation algorithm for general VC-SNDP. On the other hand, we show how to extend the analysis of iterative rounding applied to EC-SNDP to yield 2-approximation algorithms for both general ELC, and for the case of VC-SNDP when rij ∈ {0, 1, 2}. The latter result improves on an existing 3-approximation algorithm. The former is the first constant factor approximation algorithm for a general survivable network design problem that allows node failures.
Towards an Ontology of Factors Influencing Reverse Engineering
Authors: Bart Du Bois
Venue: Proceedings of the 13th IEEE International Workshop on Software Technology and Engineering Practice (2005)

In the context of the workshop's discussion on a general framework for empirical studies on reverse engineering, this paper stresses the need for an ontology of factors influencing the application of reverse engineering techniques. Through an integration of existing work, this paper proposes a tentative ontology. This work provides the first step towards an ontology facilitating communication of experimental designs and the resulting identification of relationships between experimental variables.
Automatic Image Quality Assessment with Application in Biometrics
Authors: H. Fronthaler, K. Kollreider, J. Bigun
Venue: Proceedings of the 2006 Conference on Computer Vision and Pattern Recognition Workshop (2006)

A method using local features to assess the quality of an image, with demonstration in biometrics, is proposed. Recently, image quality awareness has been found to increase recognition rates and to support decisions in multimodal authentication systems significantly. Nevertheless, automatic quality assessment is still an open issue, especially with regard to general tasks. Indicators of perceptual quality like noise, lack of structure, blur, etc. can be retrieved from the orientation tensor of an image, but there are few studies reporting on this. Here we study the orientation tensor with a set of symmetry descriptors, which can be varied according to the application. Allowed classes of local shapes are generically provided by the user but no training or explicit reference information is required. Experimental results are given for fingerprint. Furthermore, we indicate the applicability of the proposed method to face images.
Towards efficient range queries in mobile ad hoc networks using DHTs
Authors: Thomas Zahn, Georg Wittenburg, Jochen Schiller
Venue: Proceedings of the 1st international workshop on Decentralized resource sharing in mobile computing and networking (2006)

Recently, Distributed Hash Tables (DHT) explicitly designed for the use in MANETs have been proposed. Thus, many DHT-based distributed network applications from the domain of the Internet can be expected to be efficiently ported to MANETs. While the exact key lookups provided by such DHTs might be sufficient for many applications, range queries are often a desirable feature in wireless ad hoc networks (e.g. in sensor networks). However, the implementation of range queries using DHTs is a non-trivial task. In this paper we present a straight-forward implementation of Distributed Segment Trees as proposed in [4] on top of MADPastry [3] to provide DHT-based range queries for MANETs. The main goal of this work is to gain a first insight into the question whether DHT-based approaches for range queries are feasible in MANETs. First experimental results indicate that DHTs can indeed enable efficient range queries in MANETs.
A Field Programmable Memory BIST Architecture Supporting Algorithms with Multiple Nested Loops
Authors: Xiaogang Du, Nilanjan Mukherjee, Chris Hill, Wu-Tung Cheng, Sudhakar Reddy
Venue: Proceedings of the 15th Asian Test Symposium (2006)

Field Programmable Memory BIST Controllers are becoming a necessity to target manufacturing defects in embedded memories. For 65nm and below, random defects are not the only ones affecting the yield of a process. Systematic as well as parametric defects are now the predominant causes of memory failures and have to be addressed. Conventional memory BIST algorithms are usually targeted to catch random defects. In order to catch such systematic and parametric defects, it is necessary to have the flexibility to apply new algorithms to embedded memories after manufacturing. In this paper, a field programmable memory BIST architecture is proposed to support multiple loops within a test step of an algorithm, including nested loops. These controllers, therefore, guarantee supporting complex algorithm necessary to target defects during failure analysis that could help yield ramp up or reduce test escapes. In addition, the proposed architecture is modular in nature and allows optimizing the complexity of the controller along with area and performance
Resonance in n-level quantum systems
Authors: U. Boscain
Venue: Proceedings of the 2003 International Conference on Physics and Control - Volume 3 (2003)

We consider a laser-induced population transfer problem on a finite dimensional quantum system in the rotating wave approximation. For a convex cost depending only on the moduli of controls, we prove that there always exists a minimizer in resonance. These facts are quite important because they permit to reduce remarkably the complexity of the problem from dimension 2n 1 to dimension n - 1 (and extend some of our previous results for n = 2 and n = 3). Moreover, proving that resonance is optimal permits to justify some strategies used in experimental physics.
Cost curves: An improved method for visualizing classifier performance
Authors: Chris Drummond, Robert C. Holte
Venue: Machine Learning (2006)

This paper introduces cost curves, a graphical technique for visualizing the performance (error rate or expected cost) of 2-class classifiers over the full range of possible class distributions and misclassification costs. Cost curves are shown to be superior to ROC curves for visualizing classifier performance for most purposes. This is because they visually support several crucial types of performance assessment that cannot be done easily with ROC curves, such as showing confidence intervals on a classifier's performance, and visualizing the statistical significance of the difference in performance of two classifiers. A software tool supporting all the cost curve analysis described in this paper is available from the authors.
A Statistics-Based Approach to Binary Image Registration with Uncertainty Analysis
Authors: Katherine M. Simonson, Steven M. Drescher, Franklin R. Tanner
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2007)

A new technique is described for the registration of edge-detected images. While an extensive literature exists on the problem of image registration, few of the current approaches include a well-defined measure of the statistical confidence associated with the solution. Such a measure is essential for many autonomous applications, where registration solutions that are dubious (involving poorly focused images or terrain that is obscured by clouds) must be distinguished from those that are reliable (based on clear images of highly structured scenes). The technique developed herein utilizes straightforward edge pixel matching to determine the "best” among a class of candidate translations. A well-established statistical procedure, the McNemar test, is then applied to identify which other candidate solutions are not significantly worse than the best solution. This allows for the construction of confidence regions in the space of the registration parameters. The approach is validated through a simulation study and examples are provided of its application in numerous challenging scenarios. While the algorithm is limited to solving for two-dimensional translations, its use in validating solutions to higher-order (rigid body, affine) transformation problems is demonstrated.
An expressive approach to fuzzy constraint based agent purchase negotiation
Authors: Miguel A. López-Carmona, Juan R. Velasco
Venue: Proceedings of the fifth international joint conference on Autonomous agents and multiagent systems (2006)

This paper presents a fuzzy constraint based model for bilateral multi-attribute agent purchase negotiations in competitive trading environments. Argumentation is used as a key mechanism to improve agreements, in contrast to other fuzzy constraint based models which are limited to quantitative offers and counter-offers. A set of locutions and decision mechanisms which fire them are specified, so that each agent may decide its degree of cooperation and expressiveness.
Information Hiding Using Secret Sharing Scheme
Authors: Xinguang Zou, Shenghe Sun
Venue: Proceedings of the First International Conference on Innovative Computing, Information and Control - Volume 1 (2006)

In Traditional information hiding schemes, such as watermarking, the hiding information was embedded into the covermessage to form stegomessage directly. The relationship between hiding information and covermessage can not be denied. Once the existence of hiding information has been detected, the entity, who transmits the stegomessage, cannot deny that he sent some hiding information by using covermessage. To solve this problem, a novel information hiding method by using secret sharing scheme is proposed to provide plausible deniability in the paper. The method is called pre-defined secret shares (t, n) threshold scheme, which can aid hiding information sender to deny the facts of covert information sending plausibly. Additional, a proof of concept testing is also designed by using some images files of web servers as hiding information covermessage.