ppxscal/embedding_network huggingface dataset:
Discriminative Learning for Dynamic State Prediction
Authors: Minyoung Kim, Vladimir Pavlovic
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2009)

We consider the problem of predicting a sequence of real-valued multivariate states that are correlated by some unknown dynamics, from a given measurement sequence. Although dynamic systems such as the State-Space Models are popular probabilistic models for the problem, their joint modeling of states and observations, as well as the traditional generative learning by maximizing a joint likelihood may not be optimal for the ultimate prediction goal. In this paper, we suggest two novel discriminative approaches to the dynamic state prediction: 1) learning generative state-space models with discriminative objectives and 2) developing an undirected conditional model. These approaches are motivated by the success of recent discriminative approaches to the structured output classification in discrete-state domains, namely, discriminative training of Hidden Markov Models and Conditional Random Fields (CRFs). Extending CRFs to real multivariate state domains generally entails imposing density integrability constraints on the CRF parameter space, which can make the parameter learning difficult. We introduce an efficient convex learning algorithm to handle this task. Experiments on several problem domains, including human motion and robot-arm state estimation, indicate that the proposed approaches yield high prediction accuracy comparable to or better than state-of-the-art methods.
Relighting with real incident light source
Authors: Yifan Chen, Xubo Yang, Shuangjiu Xiao, Xiaodong Ding
Venue: Proceedings of the 7th IEEE/ACM International Symposium on Mixed and Augmented Reality (2008)

This paper presents an approach that can relight captured image with real incident light source. We first captured basis images of objects illuminated with a projector as the basis light source. We then established a pixel level mapping relationship between a real incident light source and the basis light source. Finally we developed a relighting algorithm that can simulate the relit effects with the real light source. The techniques can be applied to mixed reality.
Locating and paired-dominating sets in graphs
Authors: John McCoy, Michael A. Henning
Venue: Discrete Applied Mathematics (2009)

In this paper, we continue the study of paired-domination in graphs introduced by Haynes and Slater [T.W. Haynes, P.J. Slater, Paired-domination in graphs, Networks 32 (1998), 199-206]. A paired-dominating set of a graph G with no isolated vertex is a dominating set S of vertices whose induced subgraph has a perfect matching. We consider paired-dominating sets which are also locating sets, that is distinct vertices of G are dominated by distinct subsets of the paired-dominating set. We consider three variations of sets which are paired-dominating and locating sets and investigate their properties.
Sublinear-Time Algorithms for Tournament Graphs
Authors: Stefan Dantchev, Tom Friedetzky, Lars Nagel
Venue: Proceedings of the 15th Annual International Conference on Computing and Combinatorics (2009)

We show that a random walk on a tournament on n vertices finds either a sink or a 3-cycle in expected time $O\left(\sqrt{n} \cdot \log n \cdot \sqrt{\log^{*}n}\right)$, that is, sublinear both in the size of the description of the graph as well as in the number of vertices. This result is motivated by the search of a generic algorithm for solving a large class of search problems called Local Search, LS. LS is defined by us as a generalisation of the well-known class PLS.
A PDE Approach to Coupled Super-Resolution with Non-parametric Motion
Authors: Mehran Ebrahimi, Anne L. Martel
Venue: Proceedings of the 7th International Conference on Energy Minimization Methods in Computer Vision and Pattern Recognition (2009)

The problem of recovering a high-resolution image from a set of distorted (e.g., warped, blurred, noisy) and low-resolution images is known as super-resolution. Accurate motion estimation among the low-resolution measurements is a fundamental challenge of the super-resolution problem. Some recent promising advances in this area have been focused on coupling or combing the super-resolution reconstruction and the motion estimation. However, the existing approach is limited to parametric motion models, e.g., affine. In this paper, we shall address the coupled super-resolution problem with a non-parametric motion model. We address the problem in a variational formulation and propose a PDE-approach to yield a numerical scheme. In this approach, we use diffusion regularizations for both the motion and the super-resolved image. However, the approach is flexible and other suitable regularization schemes may be employed in the proposed formulation.
New Hardness Results for Diophantine Approximation
Authors: Friedrich Eisenbrand, Thomas Rothvoß
Venue: Proceedings of the 12th International Workshop and 13th International Workshop on Approximation, Randomization, and Combinatorial Optimization. Algorithms and Techniques (2009)

We revisit simultaneous Diophantine approximation, a classical problem from the geometry of numbers which has many applications in algorithms and complexity. The input to the decision version of this problem consists of a rational vector ¿ ¿ ¿ n , an error bound ¿ and a denominator bound N ¿ ¿ + . One has to decide whether there exists an integer, called the denominator Q with 1 ≤ Q ≤ N such that the distance of each number Q ·¿ i to its nearest integer is bounded by ¿. Lagarias has shown that this problem is NP-complete and optimization versions have been shown to be hard to approximate within a factor n c/ loglogn for some constant c > 0. We strengthen the existing hardness results and show that the optimization problem of finding the smallest denominator Q ¿ ¿ + such that the distances of Q·¿ i to the nearest integer are bounded by ¿ is hard to approximate within a factor 2 n unless ${\textrm{P}} = {\rm NP}$.We then outline two further applications of this strengthening: We show that a directed version of Diophantine approximation is also hard to approximate. Furthermore we prove that the mixing set problem with arbitrary capacities is NP-hard. This solves an open problem raised by Conforti, Di Summa and Wolsey.
Stability switches, oscillatory multistability, and spatio-temporal patterns of nonlinear oscillations in recurrently delay coupled neural networks
Authors: Yongli Song, Valeri A. Makarov, Manuel G. Velarde
Venue: Biological Cybernetics (2009)

A model of time-delay recurrently coupled spatially segregated neural assemblies is here proposed. We show that it operates like some of the hierarchical architectures of the brain. Each assembly is a neural network with no delay in the local couplings between the units. The delay appears in the long range feedforward and feedback inter-assemblies communications. Bifurcation analysis of a simple four-units system in the autonomous case shows the richness of the dynamical behaviors in a biophysically plausible parameter region. We find oscillatory multistability, hysteresis, and stability switches of the rest state provoked by the time delay. Then we investigate the spatio-temporal patterns of bifurcating periodic solutions by using the symmetric local Hopf bifurcation theory of delay differential equations and derive the equation describing the flow on the center manifold that enables us determining the direction of Hopf bifurcations and stability of the bifurcating periodic orbits. We also discuss computational properties of the system due to the delay when an external drive of the network mimicks external sensory input.
New Delay Optimum Quasi-Othogonal Space-Time Block Codes with Full Spatial Diversity
Authors: Changhyeon Chae, Hyunae Min, Junho Kim, Taejin Jung
Venue: Proceedings of the 2009 Eigth IEEE/ACIS International Conference on Computer and Information Science (2009)

In this paper, we propose a novel, systematic structure for quasi-orthogonal space-time block codes (QO-STBCs) achieving full rate for even number of transmit antennas over quasi-static Rayleigh fading channels. Especially, the new codes are delay optimal unlike conventional QO-STBCs and thus have a great advantage in ML decoding complexity at a receiver. In order to exploit full spatial diversity, we utilize a constellation rotation method and also examine optimal rotation angles through brute-force search for some cases of modulations and transmit antennas. Computer simulation results show that the proposed codes exhibit average error performance almost the same as or better than the existing QO-STBCs.
Photometric and geometric restoration of document images using inpainting and shape-from-shading
Authors: Li Zhang, Andy M. Yip, Chew Lim Tan
Venue: Proceedings of the 22nd national conference on Artificial intelligence - Volume 2 (2007)

The popularity of current hand-held digital imaging devices such as camera phones, PDAs, camcorders has promoted the use of digital cameras to capture document images for daily information recording purpose. However, the captured images often contain photometric and geometric distortions when the documents are of non-planar shapes, which cause significant problems to various document image analysis (DIA) tasks such as OCR. In this paper, we propose a restoration framework that removes both photometric and geometric distortions in smoothly warped document images to facilitate human perception and machine recognition. First, the photometric distortions are corrected by separating the shading image from the reflectance image using inpainting and surface fitting techniques. Next, a 2-pass Shape-from-Shading (SFS) method is exploited to recover the document's surface shape based on the extracted shading image. Once the document's shape is obtained, the geometric distortions are rectified through a physically-based flattening process. Experiments on real document images show the performance of each sub-task and demonstrate a complete solution to the restoration of physically-distorted document images.
Learning to deal with objects
Authors: Maria Malfaz, Miguel A. Salichs
Venue: Proceedings of the 2009 IEEE 8th International Conference on Development and Learning (2009)

In this paper, a modification of the standard learning algorithm Q-learning is presented: Object Q-learning (OQ-learning). An autonomous agent should be able to decide its own goals and behaviours in order to fulfil these goals. When the agent has no previous knowledge, it must learn what to do in every state (policy of behaviour). If the agent uses Q-learning, this implies that it learns the utility value Q of each action-state pair. Typically, an autonomous agent living in a complex environment has to interact with different objects present in that world. In this case, the number of states of the agent in relation to those objects may increase as the number of objects increases, making the learning process difficult to deal with. The proposed modification appears as a solution in order to cope with this problem. The experimental results prove the usefulness of the OQ-learning in this situation, in comparison with the standard Q-learning algorithm.
Therapeutic Exergaming
Authors: Brendan O'Huiginn, Barry Smyth, Garrett Coughlan, Diarmaid Fitzgerald, Brian Caulfield
Venue: Proceedings of the 2009 Sixth International Workshop on Wearable and Implantable Body Sensor Networks (2009)

Exercise therapy is prescribed by physiotherapists and rehabilitation practitioners as part of the treatment programme for many movement impairment disorders. Poor adherence and inadequate exercise technique often result in poor outcomes for these patients and delays their return to full physical function. Therapeutic exergaming, which is the use of computer games and body-worn motion tracking sensors to teach therapeutic exercise programmes to patients, may offer solutions to these problems. In this paper we describe one such system, known as FlyFit, which offers a sensor-driven flight game environment that allows physiotherapists to intuitively design game levels that will induce patients to correctly carry out their exercises programme. A 4-week pilot study to investigate the training effect of the system compared to a conventional exercise training approach is described. Results suggest these exergaming systems may induce improvements in balance and strength similar to the conventional programme along with increased levels of intrinsic motivation but further research is warranted.
An Improved Adaptive Smoothing Method
Authors: Xin Hu, Hui Peng, Joseph Kesker, Xiang Cai, William G. Wee, Jing-Huei Lee
Venue: Proceedings of the 15th International Conference on Image Analysis and Processing (2009)

An improvement of the Chen's method has been provided through the calculation of a more accurate H map. The H map is the pixel's contextual inhomogeneity value reflecting its proximity position with respect to an edge feature, and a more accurate H value leads to the more accurate smoothing speed for the pixel. While experiments on 5 real images show slight improvements in SNRs of our method over that of the Chen method, edge features preserving capability has been enhanced with low FARs (false alarm rates) for edge feature extracted from applying the Sobel filter to the image. Furthermore, parameter values have been determined through an exhaustive searching process resulting in the suggestions of h=0.4 and T=4 for practical applications where the original noise free image is not available and/or no viewer to visually make a selection of the final smoothed image as the output.
The Construction of Reverse Logistics Network about the Reusable Packages
Authors: Xiangru Meng, Hua Jiang
Venue: Proceedings of the 2009 International Conference on Measuring Technology and Mechatronics Automation - Volume 03 (2009)

Reverse logistics includes not only processing used products and processing returned merchandise due to damage, seasonal inventory, restock, recalls, and excess inventory but also reusable containers and returned packages. Good reverse logistics network can effectively make use of resource and energy, and take healthy balance between economy and environment. Reusable packaging reverse logistics network is a key component of the reverse logistics network. I put stress on how to organize the reverse logistics network, discuss to decide whether the enterprise should set up the reverse logistics network or not. If the enterprise decide to set up the reverse logistics network, it should do it itself or let the third logistics company do it? The thesis also put forward a decision-making method of reverse logistics modes to help the enterprise how to do it. Lastly put forward a reusable containers reverse logistics network-Nanchang beer company how to recycle the empty wine bottle.
NER systems that suit user's preferences: adjusting the recall-precision trade-off for entity extraction
Authors: Einat Minkov, Richard C. Wang, Anthony Tomasic, William W. Cohen
Venue: Proceedings of the Human Language Technology Conference of the NAACL, Companion Volume: Short Papers on XX (2006)

We describe a method based on "tweaking" an existing learned sequential classifier to change the recall-precision tradeoff, guided by a user-provided performance criterion. This method is evaluated on the task of recognizing personal names in email and newswire text, and proves to be both simple and effective.
Preliminary Prosodic and Gestural Characteristics of Instructing Acts in Polish Task-Oriented Dialogues
Authors: Maciej Karpiński
Venue: Cross-Modal Analysis of Speech, Gestures, Gaze and Facial Expressions: COST Action 2102 International Conference Prague, Czech Republic, October 15-18, 2008 Revised Selected and Invited Papers (2009)

In the present study, selected properties of multimodal instructing acts are discussed. Realisations of the instructing acts extracted from a corpus of task-oriented dialogues are analysed in terms of their syntactic structure, prosodic properties and accompanying gestures. The syntactic structures found in the material are similar to those found in earlier studies on map task dialogues. Deictic vocabulary is more frequent in gesture-supported instructions. The mean relative pitch range is similar to the values obtained for instructions in earlier studies and different from the values for syntactically similar questions. As opposite to verbally ill-formed instructions, the well-formed ones tend to contain at least one gestural stroke. It is shown that the relative range of pitch frequency is higher in the gesture-accompanied instructing acts. It is also noticed that prosody and gesture may play similar roles in utterances.
TAMRI: A Tool for Supporting Task Distribution in Global Software Development Projects
Authors: Ansgar Lamersdorf, Jürgen Munch
Venue: Proceedings of the 2009 Fourth IEEE International Conference on Global Software Engineering (2009)

The distribution of tasks to sites is one central activity in global software development project planning. Due to the large number of assignment possibilities, tool support seems to be adequate for supporting the evaluation and selection of task assignments. We present TAMRI, a planning tool for identifying task assignments based on multiple criteria and weighted project goals. Its implementation combines a distributed systems approach with Bayesian networks. The tool can be adapted to specific organizational environments by exchanging the underlying Bayesian network. The article presents an overview of task distribution approaches, gives three application scenarios for the tool, and shows the implementation of the tool as well as its application in the scenarios.
Analyzing spatial user behavior in computer games using geographic information systems
Authors: Anders Drachen, Alessandro Canossa
Venue: Proceedings of the 13th International MindTrek Conference: Everyday Life in the Ubiquitous Era (2009)

An important aspect of the production of digital games is user-oriented testing. A central problem facing practitioners is however the increasing complexity of user-game interaction in modern games, which places challenges on the evaluation of interaction using traditional user-oriented approaches. Gameplay metrics are instrumentation data which detail user behavior within the virtual environment of digital games, forming accurate and detailed datasets about user behavior that supplement existing user-testing methods such as playtesting and usability testing. In this paper existing work on gameplay metrics is reviewed, and spatial analysis of gameplay metrics introduced as a new approach in the toolbox of user-experience testing and research. Furthermore, Geographic Information Systems (GIS) are introduced as a tool for performing spatial analysis. A case study is presented with Tomb Raider: Underworld, showcasing the merger of GIS with gameplay metrics analysis and its application to game testing and design.
A Novelty Approach for Checking Consistency of Security Policy
Authors: Liu Changhua, Li Yaqin, Liao Zhensong
Venue: Proceedings of the 2009 International Forum on Information Technology and Applications - Volume 03 (2009)

Trust Negotiation (TN) is an approach to establishing trust relationship between strangers by disclosing iteratively credentials and access control policies. In open and distributed environment, while TN brings convenience in resource sharing, it still has some shortcomings, such as easy to fail in negotiation, difficult to track users' deed and so on. In ATN, access control policy plays a key role in protecting resources from unauthorized access. In practice, a policy may contain sensitive information, and its disclosure may cause damages. In order to protect the sensitive policy or its content, the policy is usually designed complex. Even worse, the policy may be self contradictory, which would lead the negotiation to fail. To solve such a problem, a new approach for checking policy consistency is proposed in the paper. In the approach, we analyze why the policy inconsistency happens and specify how to avoid it by simplifying a compound policy. Meanwhile, the approach is proved useful to hide policy by presenting some useful theorems to generate minimal policy set and credential set.
Bipolar Junction Effects for High Entropy Data Harvesters
Authors: Gabriel Chindris, Marius Muresan
Venue: Proceedings of the 2008 10th International Symposium on Symbolic and Numeric Algorithms for Scientific Computing (2008)

Harvesting high-entropy data from hardware generators is usually a difficult task and most of the applications will take data that is believed to contain enough entropy and use it to “seed” a cryptographic algorithm. The paper proposes an evaluation of such System On Chip device designed to harvest high-entropy data from thermal phenomena (thermal noise and avalanche noise) and to analyze “whitening” algorithms for reducing bias and correlation. Taking into account the features of System On Chip devices: complete user management of analog and digital embedded resources, the possibility of creating custom peripherals and the high level of re-usability not only for the software modules but also for embedded hardware peripherals, the new design addresses the main challenges for building true random number generators and proposes a design path and a testing procedure for high-entropy generators.
A Noise Insensitive Cluster Validity Measure for Pattern Classification
Authors: Gang Chen, Xiaoyong Guo, Tai Hu
Venue: Proceedings of the 2009 Eigth IEEE/ACIS International Conference on Computer and Information Science (2009)

When trying to discover knowledge on a collection of data, one of the first arising tasks is to identify groups of similar objects, that is, to carry out cluster analysis for obtaining data partitions. Thus, a decision must be taken for choosing the clustering result that produces the best data partition for a given data collection. In order to support such a decision, indexes for measuring the quality of a data partitioning must be constructed. So far, several cluster validity indexes have been formulated in the literatures. Each of those indexes has strengths and drawbacks when compared with the others. In the present study, an alternative cluster validity index is formulated. The proposed validity index not only takes the contribution of each pattern into consideration, but also relies on information of intra-cluster and inter-cluster distance. The main advantage of the presented index is that is insensitive to noise by introducing the Gaussian kernel into the proposed validity index. An experimental design was devised in order to determine the comparative performance of the proposed cluster validity index against DB index previously formulated in the literature. Experimental results show that the proposed index is insensitive to noise and adaptive to produce good clustering solution.
On the coincidence of two manifolds associated with the Calogero model
Authors: V. Meshcheryakov
Venue: Journal of Dynamical and Control Systems (2009)

Let R be a root system, for example, the root system associated to a semisimple Lie algebra. In [1], V. A. Golubeva and V. P. Lexin constructed two algebraic manifolds (Bethe and Dunkl manifolds) using the "universal" Dunkl operators. These manifolds were defined as subsets of the complex space ¿ N of dimension equal to the number of roots of the root system under consideration.The first manifold (Bethe manifold) is characterized by the following property: the Laplace operator constructed by means of Dunkl operators coincides with the "universal" Hamiltonian of the Calogero model. The second one (Dunkl manifold) is characterized by the property: the "universal" Dunkl operators commute.In this paper, the manifolds associated with the irreducible root system of Coxeter type are considered. We give their construction supposing that these manifolds are embedded in ¿ N/2. A theoremon the coincidence of Bethe and Dunkl manifolds is proved.