ppxscal/embedding_network huggingface dataset:
Metric embedding for kernel classification rules
Authors: Bharath K. Sriperumbudur, Omer A. Lang, Gert R. G. Lanckriet
Venue: Proceedings of the 25th international conference on Machine learning (2008)

In this paper, we consider a smoothing kernel based classification rule and propose an algorithm for optimizing the performance of the rule by learning the bandwidth of the smoothing kernel along with a data-dependent distance metric. The data-dependent distance metric is obtained by learning a function that embeds an arbitrary metric space into a Euclidean space while minimizing an upper bound on the resubstitution estimate of the error probability of the kernel classification rule. By restricting this embedding function to a reproducing kernel Hilbert space, we reduce the problem to solving a semidefinite program and show the resulting kernel classification rule to be a variation of the k-nearest neighbor rule. We compare the performance of the kernel rule (using the learned data-dependent distance metric) to state-of-the-art distance metric learning algorithms (designed for k-nearest neighbor classification) on some benchmark datasets. The results show that the proposed rule has either better or as good classification accuracy as the other metric learning algorithms.
Graphical congestion games with linear latencies
Authors: Vittorio Bilò, Angelo Fanelli, Michele Flammini, Luca Moscardelli
Venue: Proceedings of the twentieth annual symposium on Parallelism in algorithms and architectures (2008)

We introduce a new general framework for the analysis of non cooperative games with limited social knowledge. Such an incomplete knowledge is modeled by means of a social graph G in which nodes represent players and there is an edge from i to j if i knows j, with the assumption that the payoff of each player is affected only by the strategies of the adjacent ones. In particular, we consider congestion games with linear latency functions in which each player is aware only of a subset of all the other ones. We first give a complete characterization of the games possessing pure Nash equilibria, and then investigate the impact of the limited knowledge of the players on the performance of the game, in terms of price of anarchy and price of stability.
Fuzzy model-based detection of sensor faults in waste-water treatment plant
Authors: I. Skrjanc
Venue: Proceedings of the 5th WSEAS International Conference on Computational Intelligence, Man-Machine Systems and Cybernetics (2006)

In this paper detection of sensor faults in waste-water treatment plant by Gustafson-Kessel fuzzy clustering algorithm is discussed and presented. The main idea in the case of process monitoring by the use of fuzzy clustering algorithms is comparison between the fuzzy clusters for a normal operation regime and the current behavior. The detection of sensor faults was applied to the simulation model of the waste-water treatment plant, where the following measurements were obtained: influent ammonia concentration, dissolved oxygen concentration in the first aerobic reactor tank, temperature, dissolved oxygen concentration and the ammonia concentration in the second aerobic reactor. The results of fault detection based on fuzzy model are shown and discussed.
Compact roundtrip routing with topology-independent node names
Authors: Marta Arias, Lenore J. Cowen, Kofi A. Laing
Venue: Journal of Computer and System Sciences (2008)

Consider a strongly connected directed weighted network with n nodes. This paper presents compact roundtrip routing schemes with O@?(n) sized local tables and stretch 6 for any strongly connected directed network with arbitrary edge weights. A scheme with local tables of size O@?(@e^-^1n^2^/^k) and stretch min((2^k^/^2-1)(k+@e),8k^2+4k-4), for any @e>0 is also presented in the case where edge weights are restricted to be polynomially-sized. Both results are for the topology-independent node-name model. These are the first topology-independent results that apply to routing in directed networks.
MyNet: A Platform for Secure P2P Personal and Social Networking Services
Authors: Dimitris N. Kalofonos, Zoe Antoniou, Franklin D. Reynolds, Max Van-Kleek, Jacob Strauss, Paul Wisner
Venue: Proceedings of the 2008 Sixth Annual IEEE International Conference on Pervasive Computing and Communications (2008)

Recent advances in peer-to-peer (P2P) technologies will enable users to establish ubiquitous connectivity among their personal networked devices and those of others. Building on top of such technologies, we propose a platform of middleware and user interaction tools, called MyNet, that allows everyday users to easily and securely access and share with others their devices, services, and content, without requiring expertise or centralized service support. MyNet offers a more immediate and responsive alternative to the current web-based paradigm of personal and social networking, because it allows users’ distributed services and content to be accessed and shared in real-time as they are produced, directly from their personal devices. In this paper, we describe the MyNet system architecture, including secure resource discovery, service management, security framework, and the user interaction tools for building personal and social networks and sharing resources over them. We also present our proof-of-concept implementation, including mobile devices and our tests with real users.
A Behavioral Requirements Specification Approach for Interactive Multimedia Applications
Authors: Khairuddin Hashim, Johan Yousoff
Venue: Proceedings of the 19th Australian Conference on Software Engineering (2008)

This paper presents a behavioral approach to specifying interactive multimedia applications. This requirements specification approach allows one to model sequence, parallelism, branching and iteration. Transitions due to events are subdivided into automatic, user and clock. The transitions due to tasks to be done are subdivided into animate, image, sound, text and video, which are the elements of a multimedia application. The approach is relatively simple and easy to understand. A toolkit to support specification of requirements has also been developed. Future work includes the possibility of code generation translated from the text file containing information on graphical representation.
Architecting reconfigurable component-based operating systems
Authors: Juraj Polakovic, Jean-Bernard Stefani
Venue: Journal of Systems Architecture: the EUROMICRO Journal (2008)

Dynamic reconfiguration allows modifying a system during its execution, and can be used to apply patches and updates, to implement adaptive systems, dynamic instrumentation, or to support third-party modules. Dynamic reconfiguration is important in embedded systems, where one does not necessarily have the luxury to stop a running system. While several proposals have been presented in the literature supporting dynamic reconfiguration in operating system kernels, these proposals in general hardwire a fixed reconfiguration mechanism, which may be far from optimal in certain configurations. In this paper, we present a software-architecture-based approach to the construction of reconfigurable operating systems, and we show that it allows us (i) to support different mechanisms for dynamic reconfiguration, and (ii) to select between them at build time, with little or no changes in operating system and application components. Our approach relies on the use of a reflective component model and of its associated architecture description language.
Earth surface effects on active faults: An eigenvalue asymptotic analysis
Authors: Ioan R. Ionescu, Darko Volkov
Venue: Journal of Computational and Applied Mathematics (2008)

We study in this paper an eigenvalue problem (of Steklov type), modeling slow slip events (such as silent earthquakes, or earthquake nucleation phases) occurring on geological faults. We focus here on a half space formulation with traction free boundary condition: this simulates the earth surface where displacements take place and can be picked up by GPS measurements. We construct an appropriate functional framework attached to a formulation suitable for the half space setting. We perform an asymptotic analysis of the solution with respect to the depth of the fault. Starting from an integral representation for the displacement field, we prove that the differences between the eigenvalues and eigenfunctions attached to the half space problem and those attached to the free space problem, is of the order of d^-^2, where d is a depth parameter: intuitively, this was expected as this is also the order of decay of the derivative of the Green's function for our problem. We actually prove faster decay in case of symmetric faults. For all faults, we rigorously obtain a very useful asymptotic formula for the surface displacement, whose dominant part involves a so called seismic moment. We also provide results pertaining to the analysis of the multiplicity of the first eigenvalue in the line segment fault case. Finally we explain how we derived our numerical method for solving for dislocations on faults in the half plane. It involves integral equations combining regular and Hadamard's hypersingular integration kernels.
Theorems about the attractor for incompressible non-Newtonian flow driven by external forces that are rapidly oscillating in time but have a smooth average
Authors: Caidi Zhao, Shengfan Zhou, Yongsheng Li
Venue: Journal of Computational and Applied Mathematics (2008)

This paper discusses the incompressible non-Newtonian fluid with rapidly oscillating external forces g^@?(x,t)=g(x,t,t/@?) possessing the average g^0(x,t) as @?->0^+, where 00^+. Then we establish that the Hausdorff distance between the uniform attractors A"@?^V and A"0^V in space V is also less than O(@?) as @?->0^+. Finally, we show A"@?@?A"@?^V for each @?@?[0,@?"0].
Complete partitions of graphs
Authors: Magn&#x00fa;s M. Halld&#x00f3;rsson, Guy Kortsarz, Jaikumar Radhakrishnan, Sivaramakrishnan Sivasubramanian
Venue: Combinatorica (2007)

A complete partition of a graph G is a partition of its vertex set in which any two distinct classes are connected by an edge. Let cp(G) denote the maximum number of classes in a complete partition of G. This measure was defined in 1969 by Gupta [19], and is known to be NP-hard to compute for several classes of graphs. We obtain essentially tight lower and upper bounds on the approximability of this problem. We show that there is a randomized polynomial-time algorithm that given a graph G with n vertices, produces a complete partition of size &#x03a9;(cp(G)/&#x221a;lgn). This algorithm can be derandomized. We show that the upper bound is essentially tight: there is a constant C > 1, such that if there is a randomized polynomial-time algorithm that for all large n, when given a graph G with n vertices produces a complete partition into at least C&#x00b7;cp(G)/&#x221a;lgn classes, then NP &#x2286; RTime(n O(lg lg n)). The problem of finding a complete partition of a graph is thus the first natural problem whose approximation threshold has been determined to be of the form &#x0398;((lgn) c ) for some constant c strictly between 0 and 1.
Computational issues of sine wave estimation in time domain
Authors: Nikica Hlupic, Danko Basch, Krešimir Fertalj
Venue: Proceedings of the 6th WSEAS International Conference on Systems Theory & Scientific Computation (2006)

This paper elaborates the present stage and predictable direction of future development of Sine Wave Calculator (SWC), a simple method for signal analysis in time domain that provides accuracy comparable to the best classical methods (relative errors about few times 10-6). The main SWC advantages are extreme simplicity and straightforward calculations, which makes it preferable solution for quick implementation. The main shortage is still unknown mathematical analysis of errors, which are probably unequal for different signal parameters.
Modified SOR-like method for the augmented system
Authors: Xinhui Shao, Zheng Li, Changjun Li
Venue: International Journal of Computer Mathematics (2007)

The SOR-like method with two real parameters ω and α is considered for solving the augmented system. The new method is called the modified SOR-like method (MSOR-like method). The MSOR-like method becomes the SOR-like method when α = 0. The functional equation relating the parameters and eigenvalues of the iteration matrix of the MSOR-like method is obtained. Hence the necessary and sufficient condition for the convergence of the GSOR-like method is derived. It is shown that when α is negative, the convergence domain for the parameter ω for the MSOR-like method is larger than that for the SOR-like method. Finally, a numerical computation based on a particular linear system is given which clearly shows that the MSOR-like method outperforms the SOR-like method.
Differentiation of stenosed and aneurysmal arteries by pulse wave propagation analysis based on a fluid-solid interaction computational method
Authors: Tomohiro Fukui, Kim H. Parker, Ken-ichi Tsubota, Shigeo Wada, Takami Yamaguchi
Venue: Technology and Health Care (2007)

Pulse Wave Velocity (PWV) is recognized by clinicians as an index of the mechanical properties of human blood vessels. However, the measured PWV of real human blood vessels will not always obey the Moens-Korteweg equation, which describes the PWV in ideal elastic tubes. Waveform analysis has been studied as an alternative diagnosis for cardiovascular disease, and reflected waves that occur in the diseased region may be a key for the estimation of the severity of disease. In this study, we modeled stenosed and aneurysmal arteries in a three-dimensional coupled fluid-solid interaction scheme, and analyzed the pulse wave propagation in order to assess the reflected waves that occurred in the diseased region. A commercial code (Radioss, MECALOG, France) was used to solve the fluid-solid interactions. A steady flow with Reynolds number 1000 was imposed at the inlet of the artery as the basic flow, then a single rectangular pulse with Reynolds number 4000 was imposed upon the basic flow to produce a propagating wave. We showed that the reflected waves from the stenosis and the aneurysm are different in their phase, and the wavelength of the reflected waves from the aneurysm is affected by the aneurysm length.
Geometric compression of a quadrilateral mesh
Authors: Ren Chen, Xiaonan Luo, Hao Xu
Venue: Computers Mathematics with Applications (2008)

A new progressive compression algorithm for arbitrary topology with highly detailed triangle meshes is proposed in this paper. We firstly parameterize the original triangle mesh to a regular quadrilateral approximation. A wavelet transform is then applied to the approximation to remove a large amount of correlation between neighboring vertices. Finally, we used low cost zerotree coding and subdivision based reconstruction to build a sequence of progressive models. Our method will greatly reduce the cost of transportation with acceptable quality loss as shown in the experimental results.
An adaptive multipath mitigation filter for GNSS applications
Authors: Chung-Liang Chang, Jyh-Ching Juang
Venue: EURASIP Journal on Advances in Signal Processing (2008)

Global navigation satellite system (GNSS) is designed to serve both civilian and military applications. However, the GNSS performance suffers from several errors, such as ionosphere delay, troposphere delay, ephemeris error, and receiver noise and multipath. Among these errors, the multipath is one of the most unpredictable error sources in high-accuracy navigation. This paper applies a modified adaptive filter to reduce code and carrier multipath errors in GPS. The filter employs a tap-delay line with an Adaline network to estimate the direction and the delayed-signal parameters. Then, the multipath effect is mitigated by subtracting the estimated multipath effects from the processed correlation function. The hardware complexity of the method is also compared with other existing methods. Simulation results show that the proposed method using field data has a significant reduction in multipath error especially in short-delay multipath scenarios.
Notification of dangerous situation for elderly people using visual cues
Authors: Hideaki Kanai, Goushi Tsuruma, Toyohisa Nakada, Susumu Kunifuji
Venue: Proceedings of the 13th international conference on Intelligent user interfaces (2008)

There are various dangers that could lead to accidents in daily life at home. It is difficult for elderly people to realize these dangers beforehand. In this study, we focus on a method for enhancing the risk perception of elderly people. We have developed a system that enhances the awareness of dangerous situations. It performs the following functions: (1) it recognizes the behavior and situation of the elderly person, (2) it estimates the risk, and (3) when the risk is estimated to be high, it notifies the person of the risk by means of visual and audio cues. In this paper, we outline our system and report a user test that evaluates the notification function, particularly the use of visual cues in our experimental living environment. The result is that the visual cues are suitable for elderly rather than healthy people in the environment of a dark room. As a future work, we will investigate the effects of visual and audio cues as notifications of danger for elderly people.
Cleaning a network with brushes
Authors: M. E. Messinger, R. J. Nowakowski, P. Praat
Venue: Theoretical Computer Science (2008)

Following the decontamination metaphor for searching a graph, we introduce a cleaning process, which is related to both the chip-firing game and edge searching. Brushes (instead of chips) are placed on some vertices and, initially, all the edges are dirty. When a vertex is 'fired', each dirty incident edge is traversed by only one brush, cleaning it, but a brush is not allowed to traverse an already cleaned edge; consequently, a vertex may not need degree-many brushes to fire. The model presented is one where the edges are continually recontaminated, say by algae, so that cleaning is regarded as an on-going process. Ideally, the final configuration of the brushes, after all the edges have been cleaned, should be a viable starting configuration to clean the graph again. We show that this is possible with the least number of brushes if the vertices are fired sequentially but not if fired in parallel. We also present bounds for the least number of brushes required to clean graphs in general and some specific families of graphs.
An engineering approach to sociable robots
Authors: Oscar Déniz, Mario Hernández, Javier Lorenzo, Modesto CastrillÓn
Venue: Journal of Experimental Theoretical Artificial Intelligence (2007)

Robotics researchers and cognitive scientists are becoming more and more interested in so-called sociable robots. These machines normally have expressive power (facial features, voice,...) as well as abilities for locating, paying attention to, and addressing people. The design objective is to make robots which are able to sustain natural interactions with people. This capacity falls within the range classed as social intelligence in humans. This position paper argues that the reproduction of social intelligence, as opposed to other types of human ability, may lead to fragile performance, in the sense that tested cases may produce rather different performances to future (untested) cases and situations. This limitation stems from the fact that our social abilities, which appear early in life, are mainly unconscious in origin. This is in contrast with other human abilities that we carry out using conscious effort, and for which we can easily conceive algorithms and representations. This novel perspective is deemed useful for defining the obstacles and limitations of a field that is generating increasing interest. Taking into account the mentioned issues, a development approach suited to the problem is proposed. The use of this approach is demonstrated in the development of CASIMIRO, a robotic head with basic interaction abilities.
Fast multipole methods on graphics processors
Authors: Nail A. Gumerov, Ramani Duraiswami
Venue: Journal of Computational Physics (2008)

The fast multipole method allows the rapid approximate evaluation of sums of radial basis functions. For a specified accuracy, @e, the method scales as O(N) in both time and memory compared to the direct method with complexity O(N^2), which allows the solution of larger problems with given resources. Graphical processing units (GPU) are now increasingly viewed as data parallel compute coprocessors that can provide significant computational performance at low price. We describe acceleration of the FMM using the data parallel GPU architecture. The FMM has a complex hierarchical (adaptive) structure, which is not easily implemented on data-parallel processors. We described strategies for parallelization of all components of the FMM, develop a model to explain the performance of the algorithm on the GPU architecture; and determined optimal settings for the FMM on the GPU. These optimal settings are different from those on usual CPUs. Some innovations in the FMM algorithm, including the use of modified stencils, real polynomial basis functions for the Laplace kernel, and decompositions of the translation operators, are also described. We obtained accelerations of the Laplace kernel FMM on a single NVIDIA GeForce 8800 GTX GPU in the range of 30-60 compared to a serial CPU FMM implementation. For a problem with a million sources, the summations involved are performed in approximately one second. This performance is equivalent to solving of the same problem at a 43 Teraflop rate if we use straightforward summation.
Composition of DCT and Wavelet Transform for Image Compression
Authors: Xiteng Liu
Venue: Proceedings of the Data Compression Conference (2008)

The paper reports an advanced image compression algorithm based on a newly proposed standpoint of time-frequency analysis. The advanced algorithm yields 40% improvement against JPEG2000 in compression performance, which means that it attains the same image quality with 40% less data. Compared with JPEG, the improvement may reach 50%. Especially, it makes more improvement at high quality than low quality to the same image. It doubles the coding speed of JPEG2000. But the implementation complexity is only at the level of baseline JPEG.
Independent systems of representatives in weighted graphs
Authors: Ron Aharoni, Eli Berger, Ran Ziv
Venue: Combinatorica (2007)

The following conjecture may have never been explicitly stated, but seems to have been floating around: if the vertex set of a graph with maximal degree &#x0394; is partitioned into sets V i of size 2&#x0394;, then there exists a coloring of the graph by 2&#x0394; colors, where each color class meets each V i at precisely one vertex. We shall name it the strong 2&#x0394;-colorability conjecture. We prove a fractional version of this conjecture. For this purpose, we prove a weighted generalization of a theorem of Haxell, on independent systems of representatives (ISR&#x2019;s). En route, we give a survey of some recent developments in the theory of ISR&#x2019;s.