ppxscal/embedding_network huggingface dataset:
A Comparative Study of Directional Node-Disjoint Multipath Routing in Wireless Ad Hoc Network
Authors: Abhijit Saha, Shafqat-Ur-Rehman, Mikyung Kang, In-Hye Shin, Gyung-Leen Park, Junghoon Lee
Venue: Proceedings of the international conference on Computational Science and Its Applications, Part II (2008)

This paper compares the performance of on-demand Directional Node-Disjoint Multipath Routing (DNDMR) protocol with those of contemporary wireless ad hoc network routing protocols. DNDMR protocol especially performs well for grid-style network topology. Multipath routing inherently allows the establishment of multiple routes between source and destination. The important features of DNDMR are path accumulation with a novel directional method, reducing routing overhead by controlled propagation, and ensuring node-disjoint paths automatically. DNDMR improves the reliability of data communication (i.e., fault tolerance) over the wireless ad hoc network. It significantly reduces control traffic overhead and end-to-end delay, and improves throughput. We evaluate the comparative performance of DNDMR using ns-2 simulator. The performance is measured comparative to existing unipath routing (DSDV, DSR, AODV), and multipath routing (AOMDV) protocols. The simulation results reveal that DNDMR has better performance and more reliable than the contemporary unipath and multipath routing protocols.
A Version of the FastICA Algorithm Based on the Secant Method Combined with Simple Iterations Method
Authors: Doru Constantin, Luminita State
Venue: Proceedings of the 3rd international conference on Image and Signal Processing (2008)

The work proposes a new algorithm for the estimation of the ICA model, an algorithm based on secant method and successive approximations. The first sections briefly present the standard FastICA algorithm based on the Newton method and a new version of the FastICA algorithm. The proposed algorithm to estimate the independent components combines the secant iterations with successive approximations technique. The final section presents the results of a comparative analysis experimentally derived conclusions concerning the performance of the proposed method. The tests were performed of several samples of signal files.
Nonlinear Systems Modeling Using LS-SVM with SMO-Based Pruning Methods
Authors: Changyin Sun, Jinya Song, Guofang Lv, Hua Liang
Venue: Proceedings of the 4th international symposium on Neural Networks: Advances in Neural Networks (2007)

This paper firstly provides a short introduction to least square support vector machine (LS-SVM), then provides sequential minimal optimization (SMO) based on Pruning Algorithms for LS-SVM, and uses LS-SVM to model nonlinear systems. Simulation experiments are performed and indicated that the proposed method provides satisfactory performance with excellent accuracy and generalization property and achieves superior performance to the conventional method based on common LS-SVM and neural networks.
University and Hospitals of Geneva Participating at ImageCLEF 2007
Authors: Xin Zhou, Julien Gobeill, Patrick Ruch, Henning Müller
Venue: Advances in Multilingual and Multimodal Information Retrieval: 8th Workshop of the Cross-Language Evaluation Forum, CLEF 2007, Budapest, Hungary, September 19-21, 2007, Revised Selected Papers (2008)

This article describes the participation of the University and Hospitals of Geneva at three tasks of the 2007 ImageCLEF image retrieval benchmark. The visual retrieval techniques relied mainly on the GNU Image Finding Tool (GIFT) whereas multilingual text retrieval was performed by mapping the full text documents and the queries in a variety of languages onto MeSH (Medical Subject Headings) terms, using the EasyIR text retrieval engine for retrieval.For the visual tasks it becomes clear that the baseline GIFT runs do not have the same performance as more sophisticated techniques such as visual patch histograms do have. GIFT can be seen as a baseline for the visual retrieval as it has been used for the past four years in ImageCLEF in the same configuration. Whereas in 2004 the performance of GIFT was among the best systems it now is towards the lower end, showing the clear improvement in retrieval quality. Due to time constraints no further optimizations could be performed and no relevance feedback was used, one of the strong points of GIFT. The text retrieval runs have a good performance showing the effectiveness of the approach to map terms onto an ontology. Mixed runs are in performance slightly lower than the best text results alone, meaning that more care needs to be taken in combining runs. English is by far the language with the best results; even a mixed run of the three languages was lower in performance.
Remembering without Memory: Tree Exploration by Asynchronous Oblivious Robots
Authors: Paola Flocchini, David Ilcinkas, Andrzej Pelc, Nicola Santoro
Venue: Proceedings of the 15th international colloquium on Structural Information and Communication Complexity (2008)

In the effort to understand the algorithmic limitations of computing by a swarm of robots, the research has focused on the minimal capabilities that allow a problem to be solved. The weakest of the commonly used models is Asynch where the autonomous mobile robots, endowed with visibility sensors (but otherwise unable to communicate), operate in Look-Compute-Move cycles performed asynchronously for each robot. The robots are often assumed (or required to be) oblivious: they keep no memory of observations and computations made in previous cycles.We consider the setting when the robots are dispersed in an anonymous and unlabeled graph, and they must perform the very basic task of exploration: within finite time every node must be visited by at least one robot and the robots must enter a quiescent state. The complexity measure of a solution is the number of robots used to perform the task.We study the case when the graph is an arbitrary tree and establish some unexpected results. We first prove that there are n-node trees where ¿(n) robots are necessary; this holds even if the maximum degree is 4. On the other hand, we show that if the maximum degree is 3, it is possible to explore with only $O(\frac{\log n} {\log\log n})$ robots. The proof of the result is constructive. Finally, we prove that the size of the team is asymptotically optimal: we show that there are trees of degree 3 whose exploration requires $\Omega(\frac{\log n}{\log\log n})$ robots.
Flexible signature descriptions for adaptive motion trajectory representation, perception and recognition
Authors: Shandong Wu, Y. F. Li
Venue: Pattern Recognition (2009)

Motion trajectory is a meaningful and informative clue in characterizing the motions of human, robots or moving objects. Hence, it is important to explore effective motion trajectory modeling. However, with the existing methods, a motion trajectory is used in its raw data form and effective trajectory description is lacking. In this paper, we propose a novel 3D motion trajectory signature descriptor and develop three signature descriptions for motion characterization. The flexible descriptions give the signature high functional adaptability to meet various application requirements in trajectory representation, perception and recognition. The full signature, optimized signature and cluster signature are firstly defined for trajectory representation. Then we explore the motion perception from a single signature, inter-signature matching and the generalization of a cluster signature. Furthermore, three solutions for signature recognition are investigated corresponding to different signature descriptions. The conducted experiments verified the signature's capabilities and flexibility. The signature's application to robot learning is also discussed.
Correntropy as a novel measure for nonlinearity tests
Authors: Aysegul Gunduz, Jose C. Principe
Venue: Signal Processing (2009)

Nonlinearity tests have become an essential step in system analysis and modeling due to the computational demands and complexity of analysis involved in nonlinear modeling. Standard nonlinear measures are either too complicated to estimate accurately (such as Lyapunov exponents and correlation dimension), or not able to capture sufficient but not necessary conditions of nonlinearity (such as time asymmetry). Correntropy is a kernel-based similarity measure which contains the information of both statistical and temporal structure of the underlying dataset. The capability of preserving nonlinear characteristics makes correntropy a suitable candidate as a measure for determining nonlinear dynamics. Moreover, since correntropy makes use of kernel methods, its estimation is computationally efficient. Using correntropy as the test statistic, nonlinearity tests based on the null hypothesis that signals of interest are realizations of linear Gaussian stochastic processes are carried out via surrogate data methods. Experiments performed on linear Gaussian, linear non-Gaussian, and nonlinear systems with varying in-band noise levels, data lengths, and kernel sizes confirm that correntropy can be employed as a discriminative measure for detecting nonlinear characteristics in time series. Results of tests performed on data collected from natural systems are in agreement with findings in time series analysis literature.
Flexible Control Mechanism for Multi-DOF Robotic Arm Based on Biological Fluctuation
Authors: Ippei Fukuyori, Yutaka Nakamura, Yoshio Matsumoto, Hiroshi Ishiguro
Venue: Proceedings of the 10th international conference on Simulation of Adaptive Behavior: From Animals to Animats (2008)

Controlling a highly dynamics and unknown system by existing control methods would be difficult because of its complexity. Recent biological studies reveal that animals utilize biological fluctuations to achieve adaptability to the environment and high flexibility. In this paper, we propose a simple, but flexible control method inspired by a biological adaptation mechanism. The proposed method is then applied to control robotic arms. The results of simulation indicated that our proposed method can be applied well to the control of a robot with multi-DOF.
Speaker Individualities in Speech Spectral Envelopes and Fundamental Frequency Contours
Authors: Tatsuya Kitamura, Masato Akagi
Venue: Speaker Classification II: Selected Projects (2007)

Perceptual cues for speaker individualities embedded in spectral envelopes of vowels and fundamental frequency (F0) contours of words were investigated through psychoacoustic experiments. First, the frequency bands having speaker individualities are estimated using stimuli created by systematically varying the spectral shape in specific frequency bands. The results suggest that speaker individualities of vowel spectral envelopes mainly exist in higher frequency regions including and above the peak around 20---23 ERB rate (1,740---2,489 Hz). Second, three experiments are performed to clarify the relationship physical characteristics of F0 contours extracted using Fujisaki and Hirose's F0 model and the perception of speaker identity. The results indicate that some specific parameters related to the dynamics of F0 contours have many speaker individuality features. The results also show that although there are speaker individuality features in the time-averaged F0, they help to improve speaker identification less than the dynamics of the F0 contours.
NQSL - Formal Language and Tool Support for Network Quality-of-Service Requirements
Authors: Christian Webel, Reinhard Gotzhein, Joachim Nicolay
Venue: Proceedings of the 28th IFIP WG 6.1 international conference on Formal Techniques for Networked and Distributed Systems (2008)

Network Quality-of-Service (QoS) is a central characteristic of the design of modern communication systems. Before designing and implementing communication systems, network QoS requirements and QoS mappings have to be specified and analyzed. In this paper, we provide language and tool support for this purpose. To specify network QoS requirements and QoS mappings, we define a formal description technique called NQSL, the Network QoS Specification Language. To support the efficient handling of NQSL specifications, we present a tool chain consisting of the Graphical NQSL Editor (GNE), the NQSL Analyzer (NA) for QoS domain reduction, and the NQSL-to-SDL Compiler (NSC) for the generation of SDL data and process types.
Adaptive Subsampling and Motion Feature Based Fast H.264 Motion Estimation
Authors: Yiqing Huang, Qin Liu, Satoshi Goto, Takeshi Ikenaga
Venue: Proceedings of the 2008 Congress on Image and Signal Processing, Vol. 2 - Volume 02 (2008)

The latest video coding standard H.264/AVC can provide excellent performance compared with previous standards. However, the introduction of new techniques in motion estimation also brings about heavy burden of computation complexity on the video coding system. In hardware field, the subsampling technique is widely used to reduce hardware cost and release computation burden of ME engine. However, direct subsampling on video sequences will cause serious quality degradation. This paper proposes a hardware friendly fast ME algorithm which combines two complexity reduction schemes. Firstly, the pixel difference based adaptive subsampling scheme select different subsampling patterns according to the feature of current MB. Secondly, in order to fasten the ME procedure, a search position based 3-layer search range adjustment scheme is proposed to remove redundant search points. Experimental results show that about 74.17% to 90.26% ME Time can be reduced while the video quality loss is trivial. Moreover, since the two schemes are both friendly to hardware implementation, the proposed fast ME algorithm can be implanted into realtime hardwired video coding system.
The Complexity of Local List Decoding
Authors: Dan Gutfreund, Guy N. Rothblum
Venue: Proceedings of the 11th international workshop, APPROX 2008, and 12th international workshop, RANDOM 2008 on Approximation, Randomization and Combinatorial Optimization: Algorithms and Techniques (2008)

We study the complexity of locally list-decoding binary error correcting codes with good parameters (that are polynomially related to information theoretic bounds). We show that computing majority over ¿(1/¿) bits is essentially equivalent to locally list-decoding binary codes from relative distance 1/2 ¿ ¿ with list size at most poly (1/¿). That is, a local-decoder for such a code can be used to construct a circuit of roughly the same size and depth that computes majority on ¿(1/¿) bits. On the other hand, there is an explicit locally list-decodable code with these parameters that has a very efficient (in terms of circuit size and depth) local-decoder that uses majority gates of fan-in ¿(1/¿).Using known lower bounds for computing majority by constant depth circuits, our results imply that every constant-depth decoder for such a code must have size almost exponential in 1/¿ (this extends even to sub-exponential list sizes). This shows that the list-decoding radius of the constant-depth local-list-decoders of Goldwasser et al. [STOC07] is essentially optimal.
Public computer systems - a new focus for information systems research
Authors: Åke Grönlund
Venue: Information Polity (1998)

"Public Computer Systems" (PCSs) are systems used in client-organisation encounters. The purpose of this paper is to provide a framework for discussing PCSs as tools in client-organisation communication. To that end, a three-level analysis scheme for client-organisation encounters (COEs) and the potential role of PCSs as change agents for those encounters is suggested; the object level, discussing the elements of COEs, the functional level, discussing the role of PCSs as a tool for achieving changes in the functionality of the client-organisation interface, and the strategic level, discussing COE paradigms. It is concluded that PCSs provide an important new focus for IS studies because they may be used to design new social fora and make for changed roles of clients and professionals, thus affecting the terms of the societal dialogue. It is suggested that the public sector has a special responsibility for this dialogue, and that therefore strategic level analysis, largely ignored so far, should be added to the agenda of public sector information system issues.
Fuzzy SVM Training Based on the Improved Particle Swarm Optimization
Authors: Ying Li, Bendu Bai, Yanning Zhang
Venue: Proceedings of the 4th international conference on Intelligent Computing: Advanced Intelligent Computing Theories and Applications - with Aspects of Artificial Intelligence (2008)

In this paper, an improved particle swarm optimization algorithm is proposed to train the fuzzy support vector machine (FSVM) for pattern multi-classification. In the improved algorithm, the particles studies not only from itself and the best one but also from the mean value of some other particles. In addition, adaptive mutation was introduced to reduce the rate of premature convergence. The experimental results on MNIST character recognition show that the improved algorithm is feasible and effective for FSVM training.
Prioritized Overlay Multicast in Mobile Ad Hoc Environments
Authors: Li Xiao, Abhishek Patil, Yunhao Liu, Lionel M. Ni, Abdol-Hossein Esfahanian
Venue: Computer (2004)

Many proposed routing protocols for manets require nodes to maintain and update complicatedroute information, which incurs significant overhead when groups have different priorities.To address this problem, some researchers have begun focusing on application-layer, or overlay, multicast in which an overlay network forms a virtual network consisting of only member nodesatop the physical infrastructure. The authors propose a prototype of prioritized overlay multicast for manets in which participating nodes can carry out multiple functions and thus be associated with more than one overlay tree.
Research on Bio-inspired Multi-net Paralleling Mechanism Based on Web Application
Authors: Ruijuan Zheng, Huiqiang Wang, Yonggang Pang
Venue: Proceedings of the 7th international conference on Computational Science, Part III: ICCS 2007 (2007)

With the rapid development of network technologies and deteriorating of network environment, traditional single-net security system can't satisfy the security requirement. Excellent security performance of biological systems impels bio-inspired network security theory to be a hot topic currently. We advance Bio-inspired Multi-Net Security (B-MNS) system which implements the functional distributary of different subnets by state transition in Multi-Net Paralleling (MNP) mechanism. Firstly, concept model of B-MNS and MNP mechanism are outlined; secondly, parameter estimation and modifying algorithms are introduced to construct the mathematical model of B-MNS; at last, the practicability and high efficiency are proved by a simulation.
Towards an Efficient Quality Based Web Service Discovery Framework
Authors: Mossab Ahmmad Rashid Al Hunaity
Venue: Proceedings of the 2008 IEEE Congress on Services - Part I (2008)

Web service technology is playing a major role in today’s distributed system computing. Service discovery, i.e., the identification of existing WSs that can be used by new web applications, is one of the most critical problems deterring Web Service (WS) technology. Current solution is based on UDDI catalogue browsing that supports only primitive matching mechanisms and provides no control over the quality of registered services. We aim to refine the discovery process through designing a new framework that enhances retrieval algorithms by combining syntactic and semantic matching of services. The proposed framework will generate QoS information that can be utilized by new user of the service
Tutorial I: sound to image visualizations and image to sound transforms
Authors: Dionysios Politis
Venue: Proceedings of the 9th WSEAS International Conference on Acoustics & Music: Theory & Applications (2008)

Numerous algorithms have been proposed for image to sound and sound to image transforms. Based on heuristic assignments of sound frequencies to RGB values, they perform effective mappings between musical entities (notes) and values for optical wavelengths. The new element that has been recently exploited is the chromaticism of the sound domain. When taken into account, a colouring of the performed music may take place. On the other hand, segments that have acoustic polymorphism can be assigned to colours and archetypal image to sound transforms may take place. In both approaches, the visualization of music is exhibited according to the melodic structure and not only according to the temporal characteristics (i.e. rhythm).
Approximating the true evolutionary distance between two genomes
Authors: Krister M. Swenson, Mark Marron, Joel V. Earnest-Deyoung, Bernard M. E. Moret
Venue: Journal of Experimental Algorithmics (JEA) (2008)

As more and more genomes are sequenced, evolutionary biologists are becoming increasingly interested in evolution at the level of whole genomes, in scenarios in which the genome evolves through insertions, duplications, deletions, and movements of genes along its chromosomes. In the mathematical model pioneered by Sankoff and others, a unichromosomal genome is represented by a signed permutation of a multiset of genes; Hannenhalli and Pevzner showed that the edit distance between two signed permutations of the same set can be computed in polynomial time when all operations are inversions. El-Mabrouk extended that result to allow deletions and a limited form of insertions (which forbids duplications); in turn we extended it to compute a nearly optimal edit sequence between an arbitrary genome and the identity permutation. In this paper we generalize our approach to compute distances between two arbitrary genomes, but focus on approximating the true evolutionary distance rather than the edit distance. We present experimental results showing that our algorithm produces excellent estimates of the true evolutionary distance up to a (high) threshold of saturation; indeed, the distances thus produced are good enough to enable the simple neighbor-joining procedure to reconstruct our test trees with high accuracy.
Protocols for purpose-restricted anonymous communications in IP-based wireless networks
Authors: Hanane Fathi, SeongHan Shin, Kazukuni Kobara, Hideki Imai
Venue: Computer Communications (2008)

Anonymity and specifically sender anonymity have become essential requirements for many privacy-related applications (e.g. net counselling and whistle blowing). On the other hand, anonymity may be abused for various malicious activities (e.g. redistribution of copyrighted contents and illegal drug trading). In this paper, we address both by proposing protocols for authenticated anonymous communications channels. In such channels, the client can authenticate the authentication server while the latter can only authenticate the fact that the client is one of the qualified members that are eligible to use the wireless network (e.g. WLAN hot spots, WiMAX). Our protocols are based on an efficient anonymous password-based authenticated key exchange protocol and on an anonymous IP address assignment. The proposed protocols have the following advantages: (1) they can restrict the usage of the established anonymous channels to certain fair purposes; (2) they do not involve rerouting of the packets through a chain of intermediate nodes; (3) they are available right after registration of a normal password to an authentication server as for a classical non-anonymous authentication (e.g. EAP-TTLS and PEAP) and do not require any special registration procedures that would reveal initially to the authentication server that the client belongs to a small list of users of anonymous services. However, each scheme has different features with respect to the changes required of the DHCP standard, the controlled and adaptive IP address assignment, the compatibility to authentication frameworks used for wireless networks, the scalability and the number of messages involved.