检索结果-内蒙古大学图书馆

International Conference on Information technology: Coding and Computing (ITCC)

作者： J. Garofalakis E. Sakkopoulos S. Sirmakessis A. Tsakalidis Computer Engineering & Informatics Department University of Patras Patras Greece Technologies Research Unit Research Academic Computer Technology Institute Greece Hellenic Open University Patras Greece

Enterprise software infrastructure traditionally comprises a number of independent systems in order to support customer needs and business processes complicating productivity, performance and maintenance. Instead there are hypermedia facilities based on widespread standards that provide over a user-friendly, well-known framework richer functionality and features. In the paper, we present the design, implementation and evaluation of the combined use of Web services and adaptive Web-based techniques. We describe a large-scale hypermedia framework that improves the efficiency and performance of conventional enterprise activities like customer services (registration, activation, billing, support) and document management. The presented approach aims to cover these fundamental needs for a network of customers, collaborators and intranet employees.

关键词： Web services Information technology

来源：评论

学校读者我要写书评

暂无评论

Pattern recognition of EEG signals during right and left motor imagery

引用

IFAC Proceedings Volumes 2003年第16期36卷 139-144页

作者： Katsuhiro Inoue Gert Pfurtscheller Christa Neuper Kousuke Kumamaru Department of Control Engineering and Science Faculty of Computer Science and Systems Engineering Kyushu Institute of Technology 680-4 Kawazu Iizuka Fukuoka 820-8502 Japan Department of Medical Informatics Institute of Biomedical Engineering Graz University of Technology Inffeldgasse 16a 8010 Graz Austria

Electroencephalograph (EEG) recordings during right and left motor imagery can be used to move a cursor to a target on a computer screen. Such an EEG-based brain-computer interface (BCI) can provide a new communication channel to replace an impaired motor function. It can be used by e.g., handicap users with amyotrophic lateral sclerosis (ALS). In this study, statistical pattern recognition method based on AR model was introduced to discriminate the EEG signals recorded during right and left motor imagery. And learning methods (processing period for parameter estimation, AR order, etc.) were investigated. Finally, the effectiveness of our method was confirmed through the experimental studies.

关键词： EEG AR-model statistical pattern recognition brain computer interface motor imagery

来源：评论

学校读者我要写书评

暂无评论

Extreme Nash equilibria

Lecture Notes in Computer Science (including subseries Lectu...

引用

Lecture Notes in computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) 2003年 2841卷 1-20页

作者： Gairing, Martin Lucking, Thomas Mavronicolas, Marios Monien, Burkhard Spirakis, Paul Faculty of Computer Science Electrical Engineering and Mathematics University of Paderborn Fürstenallee 11 33102 Paderborn Germany Department of Computer Science University of Cyprus 1678 Nicosia Cyprus Computer Technology Institute P. O. Box 1122 261 10 Patras Greece Department of Computer Engineering and Informatics University of Patras Rion 265 00 Patras Greece

We study the combinatorial structure and computational complexity of extreme Nash equilibria, ones that maximize or minimize a certain objective function, in the context of a selfish routing game. Specifically, we assume a collection of n users, each employing a mixed strategy, which is a probability distribution over m parallel links, to control the routing of its own assigned traffic. In a Nash equilibrium, each user routes its traffic on links that minimize its expected latency cost. Our structural results provide substantial evidence for the Fully Mixed Nash Equilibrium Conjecture, which states that the worst Nash equilibrium is the fully mixed Nash equilibrium, where each user chooses each link with positive probability. Specifically, we prove that the Fully Mixed Nash Equilibrium Conjecture is valid for pure Nash equilibria and that under a certain condition, the social cost of any Nash equilibrium is within a factor of 6 + Ε, of that of the fully mixed Nash equilibrium, assuming that link capacities are identical. Our complexity results include hardness, approximability and inapproximability ones. Here we show, that for identical link capacities and under a certain condition, there is a randomized, polynomial-time algorithm to approximate the worst social cost within a factor arbitrarily close to 6 + Ε. Furthermore, we prove that for any arbitrary integer k > 0, it is NP-hard to decide whether or not any given allocation of users to links can be transformed into a pure Nash equilibrium using at most k selfish steps. Assuming identical link capacities, we give a polynomial-time approximation scheme (PTAS) to approximate the best social cost over all pure Nash equilibria. Finally we prove, that it is NP-hard to approximate the worst social cost within a multiplicative factor 2 - 2/m+1 - Ε. The quantity 2 - 2/m+1 is the tight upper bound on the ratio of the worst social cost and the optimal cost in the model of identical capacities. © Springer-Verlag Berlin Heid

关键词： Probability distributions

来源：评论

学校读者我要写书评

暂无评论

Efficient multipath channel estimation using a semi-blind parametric technique

Efficient multipath channel estimation using a semi-blind pa...

引用

International Conference on Acoustics, Speech, and Signal Processing (ICASSP)

作者： A.A. Rontogiannis A. Marava K. Berberidis J. Palicot School of Natural Resources and Enterprises Management University of Ioannina (UoI) Agrinio Greece Department of Computer Engineering & Informatics/Computer Technology Institute University of Patras Rio Greece INRIA/IRISA Rennes France

A parametric method for estimating the unknown channel impulse response (CIR) in a semi-blind manner is proposed. The main trait of this method is that, instead of seeking the whole CIR sequence, only the unknown time delays and attenuation factors of the physical channel multipath components are estimated. The technique is based on a suitable application of the subchannel response matching (SRM) criterion. The resulting cost function is separable with respect to the two sets of unknown parameters, i.e. time delays and attenuations. Thus, an efficient two step optimization procedure can be applied. The new method offers significant computational savings and a lower mean square estimation error as compared to existing semi-blind channel estimation methods.

关键词： Multipath channels Delay effects Attenuation Channel estimation Parameter estimation Delay estimation Wireless communication Least squares methods Resource management technology management

来源：评论

学校读者我要写书评

暂无评论

Dynamic-footprint based person identification using mat-type pressure sensor

Dynamic-footprint based person identification using mat-type...

引用

Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Jin-Woo Jung Z. Bien Sang-Wang Lee T. Sato Department of Electrical Engineering and Computer Science Korea Advanced Institute of Science and Technology Daejeon Korea Department of Mechano-Informatics University of Tokyo Bunkyou-Ku Tokyo Japan

Many diverse methods have been developing in the field of biometric identification as human-friendliness has been emphasized in the intelligent system's area. And one of emerging method is to use human walking behavior. But, in the previous methods based on human gait, stable somewhat long-term walking data are an essential condition for person recognition. Therefore, these methods are difficult to cope with various change of walking velocity which may be generated frequently during real walking. In this paper, we suggest a new method which uses just one-step walking data from mat-type pressure sensor. When a human walk through the pressure sensor, we get quantized COP (center of pressure) trajectory and HMM (hidden Markov model) is used to make probability models for user's each foot. And then, HMMs for two feet are combined for better performance by Levenberg-Marquart learning method. Finally, we prove the usefulness of the suggested method using 8 people recognition experiments.

关键词： Legged locomotion Hidden Markov models Identification of persons Biometrics Face recognition Sensor systems Learning systems Fingerprint recognition

来源：评论

学校读者我要写书评

暂无评论

Synchronous machine-turbine drive system with indirect speed control

Synchronous machine-turbine drive system with indirect speed...

引用

IEEE International Conference on Electric Machines and Drives (IEMDC)

作者： R.K. Jardan I. Nagy Faculty of Electrical Engineering and Informatics Department of Automation and Applied Informatics Budapest University슠of슠Technology슠and슠Economics Budapest Hungary Computer and Automation Institute Hungarian Academy of Sciences (ATOMKI) Budapest Hungary

Dynamic properties of a hybrid system are analyzed that has been developed to generate electric energy by utilizing alternative, renewable and waste energies. The solution is based on a system that consists of a high-speed turbine, coupled to a three-phase permanent magnet synchronous generator, an AC/AC converter and a supervisory control unit. The function of the system is to utilize the energy content of some working medium by a special turbine that converts the energy content of the working medium into electric energy by the generator and the AC/AC converter. The alternative renewable energy sources may include solar energy (direct solar steam system or solar energy with heat exchanger), geothermal energy (with or without heat exchanger) and energy obtained from biomass. Various waste energy sources can also be utilized by applying the system such as the energy that can be obtained during the process of pressure reduction in steam, gas and fluid networks. The electric power generated by the system can be fed back to the utility mains or it can be used in stand-alone mode to supply a selected group of loads. The paper analyses a novel control strategy and principle of the system to ensure optimum performance and economy by using a special solution for ensuring the power equilibrium in the combined mechanical-electric drive.

关键词： Velocity control Turbines Geothermal power generation Solar energy Solar heating Magnetic analysis Hybrid power systems Couplings Permanent magnets Synchronous generators

来源：评论

学校读者我要写书评

暂无评论

Nonlinear model structure identification of complex biomedical data using a genetic programming based technique

Nonlinear model structure identification of complex biomedic...

引用

IEEE International Symposium on Intelligent Signal Processing

作者： G.N. Beligiannis L.V. Skarlas S.D. Likothanassis K. Perdikouri University of Patras Artificial Intelligence Research Center (U.P.A.I.R.C.) University of Patras Patras Greece Computer Technology Institute Patras Greece Department of Computer Engineering and Informatics University of Patras Patras Greece University of Patras Patras GR Dept. of Comput. Eng. & Informatics Patras Univ. Greece

In this contribution, a genetic programming based technique, which combines the ability of genetic programming to explore both automatically and effectively, the whole set of candidate model structures and the robustness of evolutionary multimodel partitioning filters, is presented. The method is applied to the nonlinear system identification problem of complex biomedical data. Simulation results show that the algorithm identifies the true model and the true values of the unknown parameters for each different model structure, thus assisting the genetic programming technique to converge more quickly to the (near) optimal model structure. The method has all the known advantages of the evolutionary multimodel partitioning filters, that is, it is not restricted to the Gaussian case, it is applicable to online/adaptive operation and is computationally efficient. Furthermore, it can be realized in a parallel processing fashion, a fact, which makes it amenable to VLSI implementation.

关键词： Bioinformatics Genetic programming Autoregressive processes Signal processing algorithms Nonlinear systems Mathematical model Biomedical signal processing Nonlinear dynamical systems Biomedical computing Biomedical engineering

来源：评论

学校读者我要写书评

暂无评论

Secure information hiding based on computationally intractable problems

引用

Journal of Discrete Mathematical Sciences and Cryptography 2003年第1期6卷 21-33页

作者： Armeni, S. Christodulakis, D. Kostopoulos, I. Stamatiou, Y.C. Xenos, M. Department of Computer Engineering and Informatics University of Patras Patras 26500 Rio Greece Computer Technology Institute Patras GR-261 10 61 Riga Ferraiou Str. Greece Hellenic Open University Patras 262 23 Sachtouri 16 Greece

In this work, a method for proving copyright ownershipis presented that is based on Zero Knowledge Interactive Proof (ZKIP) protocols for computationally intractable problems. The utilized problem is the 3-coloring problem, which consists in assigning one of three available colors to the vertices of a graph so that no two adjacent vertices have the same color. Using the presumed computational intractability of this problem, the construction of large signatures is proposed so that they represent adjacency matrices of random, 3-colorable graphs. Since itis easy to construct large graphs with a prescribed 3-coloring of their vertices whereas it is difficult to discover such a 3-coloring, the owner of a copyrighted digital piece of work (e.g. image, audio, video) may easily generate a random 3-colorablegraph, embed it in the digital object and then use the knowledge of the 3-coloring in debates over the object’s ownership. Due to the intractability of the 3-coloring problem, only the owner is able to produce it sufficiently fast in an ownershipchallenge so as to convince a third party that the graph was indeed embedded in the object by herself/himself. Since graphs with maximum possible resistance to well-known coloring algorithms is required, we exploit some relatively recent experimental and theoretical findings suggesting that hard 3-coloringinstances are found among graphs having a vertices to edges ratio around a specific threshold value. The proposed scheme has the additional advantage that disclosing the signature is of no consequences since it is essentially the knowledge of a characteristic of the signature, i.e. the 3-coloring of the graph it represents, that enables one to use it as proof of ownership of some digital object that contains it. Even if someone managed to locateand extract the signature, to use it would require a fast solution to a computationally intractable problem on some hard instance. Our proposal represents a shift from signatures that are

关键词： 3-coloring Cryptography Data hiding Graph theory Hard combinatorial instances NP-completeness Zero knowledge interactive proof (ZKIP) protocol

来源：评论

学校读者我要写书评

暂无评论

A delay systems approach to linear differential repetitive processes: Controllability and optimization

引用

IFAC Proceedings Volumes 2003年第19期36卷 333-338页

作者： S. Dymkou E. Rogers M. Dymkov K. Gałkowski D.H. Owens School of Information Technology and Mathematical Sciences University of Ballarat Victoria 33353 Australia Department of Electronics and Computer Science University of Southampton Southampton SO 17 1BJ UK Institute of Mathematics National Academy of Sciences of Belarus Surganov 11 220072 Minsk Belarus Institute of Control and Computation Engineering Technical University of Zielona Góra Poland Department of Automatic Control and Systems Engineering University of Sheffield Sheffield S1 3JD. UK

Differential linear repetitive processes are a class of continuous-discrete 2D linear systems of both systems theoretic and applications interest. The feature which makes them distinct from other classes of such systems is that information propagation in one of the two independent directions only occurs over a finite interval. Applications areas include iterative learning control and iterative solution algorithms for classes of dynamic nonlinear optimal control problems based on the maximum principle. In this paper, we investigate further the structural links between differential linear repetitive processes and a special class of time delay systems. This leads to some significant new controllability and optimal control results for these processes.

关键词： Repetitive processes time delay approaches controllability optimization

来源：评论

学校读者我要写书评

暂无评论

Preface

引用

Theoretical computer Science 2003年第1期291卷 1-1页

作者： Shay Kutten Paul Spirakis Department of Electrical Engineering Area of Information Systems Faculty of Industrial Engineering and Management The Technion-IIT 32000 Haifa Israel Computer Technology Institute Greece and Computer Engineering and Informatics Department Patras University Greece

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：