检索结果-内蒙古大学图书馆

IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC)

作者： Antonios Alexiou Christos Bouras Vasileios Kokkinos George Tsichritzis Computer Engineering and Informatics Department University of Patras Patras Greece Research Academic Computer Technology Institute University of Patras Patras Greece University of Patras Patras GR

Long Term Evolution (LTE) is the latest step towards the 4th generation (4G) of radio technologies designed to increase the capacity and speed of mobile communications. To support Multimedia Broadcast/Multicast Services (MBMS), LTE offers the possibility to transmit Multimedia Broadcast multicast service over a Single Frequency Network (MBSFN), where a time-synchronized common waveform is transmitted from multiple cells for a given duration. In this paper we analytically present the MBSFN delivery method and evaluate its performance. The critical parameters of primary interest for the evaluation of the scheme are the packet delivery cost and its scalability. To this direction, a telecommunication cost analysis of the MBMS service is presented based on the transmission cost over the air interface, as well as the costs of all interfaces and nodes of the MBSFN architecture. Since the performance of the MBSFN scheme mainly depends on the configuration of the LTE network that is under investigation, we consider different network topologies, MBSFN deployments and user distributions.

关键词： Synchronization Topology Interference Equations Multimedia communication Protocols

来源：评论

学校读者我要写书评

暂无评论

Fluctuated peer selection policy and its performance in large-scale multi-agent systems

引用

Web Intelligence and Agent Systems 2010年第3期8卷 255-268页

作者： Sugawara, Toshiharu Fukuda, Kensuke Hirotsu, Toshio Sato, Shin-Ya Akashi, Osamu Kurihara, Satoshi Dept. of Computer Science and Engineering Waseda University Shinjuku Tokyo 169-8555 Japan National Institute of Informatics Chiyoda Tokyo 101-8430 Japan NTT Network Innovation Laboratories Musashino Tokyo 180-8585 Japan Faculty of Information Science Hosei University Koganei Tokyo 184-8584 Japan Institute of Scientific and Industrial Research Osaka University Osaka 567-0047 Japan

This paper describes how, in large-scale multi-agent systems, each agent's adaptive selection of peer agents for collaborative tasks affects the overall performance and how this performance varies with the workload of the system and with fluctuations in the agents' peer selection policies (PSP). An intelligent agent in a multi-agent system (MAS) often has to select appropriate agents to assign tasks that cannot be executed locally. These collaborating agents are usually chosen according to their skills. However, if multiple candidate peer agents still remain a more efficient agent is preferable. Of course, its efficiency is affected by the agent' workload and CPU performance and the available communication bandwidth. Unfortunately, as no agent in an open environment such as the Internet can obtain such data from any other agent, this selection must be done according to the available local information about the other known agents. However, this information is limited, usually uncertain and often obsolete. Agents' states may also change over time, so the PSP must be adaptive to some extent. We investigated how the overall performance of MAS would change under adaptive policies in which agents selects peer agents using statistical/reinforcement learning. We particularly focused on mutual interference for selection under different workloads, that is, underloaded, near-critical, and overloaded situations. This paper presents simulation results and shows that the overall performance of MAS highly depends on the workload. It is shown that when agents' workloads are near the limit of theoretical total capability, a greedy PSP degrades the overall performance, even after a sufficient learning time, but that a PSP with a little fluctuation, called fluctuated PSP, can considerably improve it. © 2010 - IOS Press and the authors. All rights reserved.

关键词： Multi agent systems

来源：评论

学校读者我要写书评

暂无评论

Experimental comparison of algorithms for interference control in ad-hoc wireless networks

Experimental comparison of algorithms for interference contr...

引用

IEEE Mediterranean Electrotechnical Conference

作者： Stavros Athanassopoulos Christos Kaklamanis Evi Papaioannou Constantinos Tsantilas Research Academic Computer Technology Institute & Department of Computer Engineering and Informatics University of Patras

ISBN: (纸本)9781424457939

Interference is an issue of outstanding importance for efficient communication in ad-hoc wireless networks. Interference arises due to overlapping transmission power levels of nodes and causes message collisions that require energy-consuming retransmissions. In this work we study algorithms for interference control in ad-hoc wireless networks in the Euclidean space that aim at constructing low-interference network topologies with particular properties preserving network connectivity. We survey relative research work on such algorithms and provide implementations for four such algorithms comparing them on random geometric instances of the problem in the Euclidean space in average-case networks. Our experiments show that our implementations obtain in practice improved performance compared to corresponding theoretical bounds. Our findings confirm that sparse topologies do not automatically imply low interference and, furthermore, imply that a unified model for decreasing simultaneously both edge- and node-interference remains hard to define.

关键词： Energy consumption Interference Ad-hoc wireless networks Algorithms Communication efficiency Experimental evaluation

来源：评论

学校读者我要写书评

暂无评论

Implementing a Mobile Campus Using MLE Moodle

Implementing a Mobile Campus Using MLE Moodle

引用

International Conference on P2P, Parallel, Grid, Cloud and Internet Computing (3PGCIC)

作者： Fatos Xhafa Santi Caballé Isaac Rustarazo Leonard Barolli Department of Languages and Informatics Systems Technical University of Catalonia Spain Dept. of Languages and Informatics Systems Technical University of Catalonia Spain Department of Computer Science Multimedia and Telecommunication Open University of Catalonia Spain Dept. of Computer Science Multimedia and Telecommunication Open University of Catalonia Spain Dept. of Information and Communication Engineering Fukuoka Institute of Technology Japan

Mobile learning is considered the next step of online learning by incorporating mobility as a key requirement. Indeed, the current wide spread of mobile devices and wireless technologies brings an enormous potential to e-learning, in terms of ubiquity, pervasiveness, personalization, flexibility, and so on. For this reason, Mobile Learning is attracting significant research efforts covering a fairly variety of learning settings, from schools and universities to workplaces and cities. This research has evidenced that mobile technology can offer new opportunities for learners to learn inside and beyond the traditional instructor-oriented educational paradigm. However, mobile technologies are still in its infancy and many challenges arise. In this paper we analyze, from both learning and technological perspectives, the development of learning applications using mobile devices. To this end, proxy and proxy less architectures are considered as way to extend traditional virtual campuses with mobile clients. The objective is twofold: to access learning materials and to support learning activities. A prototype of a Virtual Campus is developed using MLE-Moodle -the Mobile Learning module of Moodle. The proposed Virtual Campus enables mobile clients to perform online learning activities and is a step towards achieving the “anytime, anywhere” paradigm.

关键词： Mobile communication Mobile handsets computer architecture Servers Context Collaboration Mobile computing

来源：评论

学校读者我要写书评

暂无评论

Performance/Robustness Limit Evaluation for Lyapunov-Stable Nonlinear Plants

引用

IFAC Proceedings Volumes 2010年第10期43卷 202-207页

作者： Cs. Bányász L. Keviczky Computer and Automation Research Institute of the H. Ac. of Sc. Control Engineering Research Group of the H. Ac. of Sc.at the Dept. of Automation and Informatics Budapest Univ. of Technology and Economics H-1111 Budapest Kende u 13-17 HUNGARY

Lyapunov-stable nonlinear plants can be approximated by an LTI model in many cases. If this approximation is obtained then it is possible to construct a G2DOF control system. The paper presents a new approach how the important relationships between the actuator, process and design parameters furthermore robustness measures can be determined. In this decomposition method the optimal control design for two-degree of freedom time delay control systems is discussed. Using a proper CAD algorithm the exact relationships can be plotted and the ultimate robustness limit of any control can be explicitly calculated.

关键词： nonlinear control Lyapunov stability performance analysis robustness limit

来源：评论

学校读者我要写书评

暂无评论

Video Transmission over TFRC using cross-layer power management

Video Transmission over TFRC using cross-layer power managem...

引用

International Conference on Software, Telecommunications and computer Networks

作者： Bouras, Christos Gkamas, Apostolos Kapoulas, Vaggelis Papapanagiotou, Vassilis Stamos, Kostas Zaoudis, Giannis Research Academic Computer Technology Institute Computer Engineering and Informatics Dept. University of Patras Greece

ISBN: (纸本)9781424449736

This paper presents the issues related to efficient transmission of encoded video (such as H.264) over wireless links using the TFRC protocol. It proposes a novel mechanism that utilizes cross-layer approaches for adaptation of the power transmission level of the sender and feedback information regarding the wireless connection status from the receiver for improved transmission statistics and therefore user experience without unnecessary power consumption. The mechanism is tested through simulations using ns2. Compared to the operation of the video transmission without the mechanism, we observe that it has benefits in terms of video quality.

关键词： Image communication systems

来源：评论

学校读者我要写书评

暂无评论

Extended TP model transformation for polytopic representation of impedance model with feedback delay

引用

WSEAS Transactions on Systems and Control 2010年第9期5卷 701-710页

作者： Galambos, Péter Baranyi, Péter Korondi, Péter Computer and Automation Research Institute Hungarian Academy of Sciences Cognitive Informatics Group Kenede u. 13-17 H-1111 Budapest Hungary Budapest University of Technology and Economics Dept. of Manufacturing Science and Technology Kenede u. 13-17 H-1111 Budapest Hungary Budapest University of Technology and Economics Dept. of Telecommunications and Media Informatics Kenede u. 13-17 H-1111 Budapest Hungary Budapest University of Technology and Economics Dept. of Mechatronics Optics and Engineering Informatics Kenede u. 13-17 H-1111 Budapest Hungary

In force controlled industrial robots, haptic and telemanipulation devices stability and control performance are contradicting requirements. In distributed systems where the sensors, actuators and control logic are separated in space, due to the network delays the control process may become unstable. In our research, we consider the coupled impedance type control algorithms as common used method in telemanipulation and interaction control of robots. In this paper, an extended TP model transformation is proposed to convert the delayed system into a polytopic tensor product (TP) model considering the value of the feedback delay as a parameter. Using such model, controller design become tractable as it does not contain feedback delay. A numerical example for a single degree of freedom impedance model with feedback delay is discussed. The results are confirmed by simulation.

关键词： Industrial robots

来源：评论

学校读者我要写书评

暂无评论

Assessment of NER solutions against the first and second CALBC Silver Standard Corpus

Assessment of NER solutions against the first and second CAL...

引用

4th International Symposium on Semantic Mining in Biomedicine, SMBM 2010

作者： Rebholz-Schuhmann, Dietrich Yepes, Antonio Jimeno Li, Chen Kafkas, Senay Lewin, Ian Kang, Ning Corbett, Peter Milward, David Buyko, Ekaterina Beisswanger, Elena Hornbostel, Kerstin Kouznetsov, Alexandre Witte, René Laurila, Jonas B. Baker, Christopher J.O. Kuo, Cheng-Ju Clematide, Simone Rinaldi, Fabio Farkas, Richárd Móra, György Hara, Kazuo Furlong, Laura Rautschka, Michael Neves, Mariana Lara Pascual-Montano, Alberto Wei, Qi Collier, Nigel Chowdhury, Md. Faisal Mahbub Lavelli, Alberto Berlanga, Rafael Morante, Roser Van Asch, Vincent Daelemans, Walter Marina, José Luís Van Mulligen, Erik Kors, Jan Hahn, Udo EMBL Outstation European Bioinformatics Institute Hinxton Cambridge CB10 1SD United Kingdom Dept. of Medical Informatics Erasmus University Medical Center Rotterdam NL Netherlands Linguamatics Ltd. St. John's Innovation Centre Cambridge United Kingdom Lab. Friedrich-Schiller-Universität Jena Germany Dept. of Computer Science and Applied Statistics University of New Brunswick Canada Dept. of Computer Science and Software Engineering Concordia University Montreal Canada Institute of Information Science Academia Sinica Taipei 115 Taiwan University of Zürich Switzerland Research Group on Artificial Intelligence Hungarian Academy of Sciences Hungary Institute of Science and Technology Nara Japan IMIM DCEX Universitat Pompeu Fabra Barcelona Spain Madrid Spain National Institute of Informatics Tokyo Japan Fondazione Bruno Kessler Trento Italy Universitat Jaume I Spain CLiPS University of Antwerp Belgium Complutense University of Madrid Spain

Background: Text mining challenges have been organised to measure the performance of automatic text mining solutions against a manually annotated gold standard corpus (GSC). The preparation of the GSC is timeconsuming and costly and the final corpus consists at the most of a few thousand documents annotated with a limited set of semantic groups. To overcome these shortcomings, the CALBC project partners (PPs) have produced a large-scale annotated biomedical corpus with four different semantic groups through the harmonisation of annotations from automatic text mining solutions, the first version of the Silver Standard Corpus (SSC-I). The four semantic groups were chemical entities and drugs (CHED), genes and proteins (PRGE), diseases and disorders (DISO) and species (SPE). This corpus has been used for the First CALBC Challenge asking the participants to annotate the corpus with their annotation solutions.

关键词： Semantics

来源：评论

学校读者我要写书评

暂无评论

ICT BONE views on the network of the future: The role of optical networking

ICT BONE views on the network of the future: The role of opt...

引用

2010 12th International Conference on Transparent Optical Networks, ICTON 2010

作者： Politi, Christina Tzanakaki, Anna O'Mahony, Michael Katrinis, Kostas Van Daele, Peter Pickavet, Mario Simeonidou, Dimitra Stavdas, Alexandros Franzl, Gerald Mitchell, John Castoldi, Piero Spadaro, Salvatore Callegatti, Franco Petropoulos, Periklis Vlachos, Kyriakos Pattavina, Achille Department of Telecommunications Science and Technology University of Peloponnese Tripolis Terma Karaiskaki 22100 Greece Athens Information Technology Markopoulo Avenue Peania 19002 Athens Greece University of Essex Wivenhoe Park CO43SQ United Kingdom IBBT Ghent University Belgium Vienna University of Technology Favoritenstr. 9/388 1040 Vienna Austria Department of Electronic and Electrical Engineering UCL Torrington Place London WC1E 7JE United Kingdom Scuola Superiore Sant'Anna Via Moruzzi 1 56124 Pisa Italy Universitat Politècnica de Catalunya Barcelona Spain DEIS University of Bologna Via Venezia 52 47023 Cesena Italy Optoelectronics Research Centre University of Southampton Southampton SO17 1BJ United Kingdom Computer Engineering and Informatics Department Research Academic Computer Technology Institute University of Patras Rio Greece Dept. of Electronics and Information Politecnico di Milano Italy

ISBN: (纸本)9781424477975

Part of the activities of the ICT EU Network of Excellence "Building the future Optical Network in Europe" (BONE) project is the development of the European Roadmap on Optical Networking in the context of the "Network of the Future". This paper presents a summary of the views of the BONE consortium as they were developed in the framework of the Roadmap activity. The methodology followed in the development of the BONE Roadmap was firstly to identify and analyse the status of broadband access penetration as well as the availability of specific network and IT technologies in various European countries. The data collected were then processed and translated into the traffic volume (distributed across different European countries) that a Pan- European network would need to support. This information is then used as the basis of a WDM optical network dimensioning exercise performed with the aim of identifying the scale of the required optical network. In addition, based on estimations regarding the evolution of broadband access technologies and the degree of broadband penetration and network services and applications, extrapolations regarding the growth of traffic to be supported by the European Network of the Future were made in a systematic manner. These were also used to dimension and understand the requirements of the European Network of the Future. This paper presents the relevant results and also provides a discussion on the BONE consortium views on the Network of the Future from an architectural and technology perspective and an outlook of the relevant key research challenges and possible solutions. © 2010 IEEE.

关键词： Fiber optic networks

来源：评论

学校读者我要写书评

暂无评论

Two-level optimized tone mapping for high dynamic range images

Two-level optimized tone mapping for high dynamic range imag...

引用

IEEE International Conference on Image Processing

作者： Chun Hung Liu Oscar C. Au Cheuk Hong Cheng Ka Yue Yip Dept. of Management & Information N.O.U Lu Chow New Taipei City Dept. of Inform. Management Ming Hsin Institute of Technology Hsin Chu Taiwan Dept. of Computer Science and Inform. Engineering Chiao Tung University Taiwan Intel Barcelona Research Center Intel Labs - Universitat Politècnica de Catalunya Dept. of Informatics University of Bergen Bergen Norway

In this paper, we propose a two-step tone-mapping algorithm to convert a high dynamic range (HDR) image to a low dynamic range (LDR) image. The first step S1 constructs a global tone mapping which optimizes between uniform quantization and histogram equalization. The second step S2 improves the visual quality by optimizing between global operation and local contrast maintenance. Both S1 and S2 can operate independent of each other. Simulation results suggest that proposed tone mapping algorithm can give good visual quality, with S1+S2 better than S1 alone. Simulation results also suggest that proposed S2 can be combined with other existing tone mapping methods to achieve improved local contrast.

关键词： Dynamic range Histograms Visualization Pixel Optimization Cameras Simulation

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：