检索结果-内蒙古大学图书馆

International conference on Advanced Learning Technologies (ICALT)

作者： Ching-Chieh Kiu Chien-Sing Lee Faculty of Information Technology Multimedia University Cyberjaya Malaysia

Ontologies enable learning objects sharing and reuse in a contextual learning environment and provide better search and navigation of learning objects. Ontologies add semantics to content components, which provide context to learning objects. This paper presents the use of Formal Concept Analysis (FCA) to structure knowledge ontologically and the self-organizing map (SOM) to reduce the problem size. To gain better visualization of the intrinsic relationship between ontological concepts, k-means clustering is applied on the clustered SOM.

关键词： Ontologies Navigation Visualization Clustering algorithms Information technology Packaging Vocabulary Learning systems Data mining Unsupervised learning

来源：评论

学校读者我要写书评

暂无评论

Chaotic video objects encryption based on mixed feedback, multiresolution decomposition and time-variant S-boxes

Chaotic video objects encryption based on mixed feedback, mu...

引用

IEEE International conference on Image Processing

作者： K.S. Ntalianis S.D. Kollias Electrical and Computer Engineering Department National and Technical University of Athens Athens Greece

The increasing popularity of multimedia applications creates an increasing need for secure storage and transmission techniques. Especially wireless communications, which can be easily intercepted, should be protected by eavesdroppers. Towards this direction, several encryption schemes have been proposed in literature, however most of them do not consider regions of interest (video objects). These regions may need better protection, may be the only regions that need protection, or should be accessed separately according to different privileges. For these reasons in this paper a video objects chaotic encryption system is proposed. Initially stereoscopic pairs are analyzed and video objects are automatically extracted using a color segments fusion approach. Next for each video object multiresolution decomposition is performed and the pixels of the lowest resolution level are encrypted using a chaotic cipher module. Finally the encrypted regions are propagated to the higher resolution levels and the encryption process is repeated until the highest level is reached. The system presents robustness against known cryptanalytic attacks, enables layered access of multimedia content and the overall security can be enhanced due to region topology.

关键词： Chaos Cryptography Feedback Chaotic communication Protection Secure storage Wireless communication Color Robustness multimedia systems

来源：评论

学校读者我要写书评

暂无评论

A Learning Management System Including Laboratory Experiments on Measurement Instrumentation

A Learning Management System Including Laboratory Experiment...

引用

IEEE Instrumentation and Measurement Technology conference

作者： S. Rapuano F. Zoino Department of Engineering University of Sannio Benevento Italy

The paper presents a comprehensive approach to distance learning for electric and electronic measurement courses. The proposed approach integrates a traditional learning management system (LMS) with the remote access to real instrumentation located in different laboratories, without requiring specific software components on the client side. The advantages of using LMSs in distance learning of measurement related topics are summarized focusing on the LMS characteristics. Then, the remote laboratory system relying on virtual instruments (Vis) developed in LabVIEW and its integration with a commercial LMS is described referring to a project financed by the Italian Ministry of Education and University

关键词： Instruments Least squares approximation Electric variables measurement Computer aided instruction content management Education Remote laboratories Electronic learning multimedia databases Software systems

来源：评论

学校读者我要写书评

暂无评论

Achieving per-stream QoS with distributed airtime allocation and admission control in IEEE 802.11e wireless LANs

Achieving per-stream QoS with distributed airtime allocation...

引用

IEEE Annual Joint conference: INFOCOM, IEEE Computer and Communications Societies

作者： Chun-Ting Chou S.N. Shankar K.G. Shin Philips Research USA Briarcliff Manor NY USA Real-Time Computing Laboratory University of Michigan Ann Arbor MI USA

To support the transmission of (high-rate and oftenbursty) multimedia data with performance guarantees in an IEEE 802.11e wireless local area network (LAN), it is crucial to design judicious algorithms for admission control and resource allocation. The traffic specification element (TSPEC) of the new IEEE 802.11e standard is used to facilitate the design of the admission control. Based on the traffic profile given in the TSPEC and the dual-token bucket regulation, a guaranteed rate is derived for our airtime-based admission control. The admission control is integrated with the contention-based enhanced distributed channel access (EDCA), which together can provide so-called "parameterized QoS" - as in the polling-based HCF controlled channel access (HCCA) - via a new distributed, quantitative control of stations' airtime usage. We also extend the current QoS signaling of HCCA defined in IEEE 802.11e to perform admission control for this enhanced EDCA. Furthermore, we extend the integrated scheme for QoS provisioning in ad hoc wireless LANs and design appropriate signaling procedures. We evaluate via simulation the effectiveness of this parameterized QoS-capable EDCA scheme, and demonstrate its advantages over the centralized, polling-based HCCA scheme.

关键词： Admission control Wireless LAN Local area networks Streaming media multimedia systems USA Councils Telecommunication traffic Communication system traffic control Resource management Laboratories

来源：评论

学校读者我要写书评

暂无评论

Search with probabilistic guarantees in unstructured peer-to-peer networks

Search with probabilistic guarantees in unstructured peer-to...

引用

International conference on Peer-to-Peer Computing

作者： R.A. Ferreira M.K. Ramanathan A. Awan A. Grama S. Jagannathan Department of Computer Sciences Purdue University West Lafayette IN USA

Search is a fundamental service in peer-to-peer (P2P) networks. However, despite numerous research efforts, efficient algorithms for guaranteed location of shared content in unstructured P2P networks are yet to be devised. In this paper, the authors presented a simple but highly effective protocol for object location that gives probabilistic guarantees of finding even rare objects independently of the network topology. The protocol relies on randomized techniques for replication of objects (or their references) and for query propagation. The authors proved analytically, and demonstrated experimentally, that this scheme provides high probabilistic guarantees of success, while incurring minimal overhead. The performance of this scheme was quantified in terms of network messages, probability of success, and response time. The robustness of this protocol was also evaluated in the presence of node failures (departures). Using simulation, it is shown that this scheme performs no worse than the best known access-frequency based protocols, without compromising access to rare objects.

关键词： Intelligent networks Peer to peer computing Frequency Network topology access protocols Computer networks Delay Robustness Routing Large-scale systems

来源：评论

学校读者我要写书评

暂无评论

Video streaming on moving vehicles over seamless internetworks of WLANs and cellular networks

Video streaming on moving vehicles over seamless internetwor...

引用

IEEE International conference on Vehicular Electronics and Safety (ICVES)

作者： Ming Li RuiMin Hu Rong Zhu Wei Li Key Laboratory of Multimedia and Network Communications Engineering Wuhan Hubei China

Interworking between wireless LANs and 3G networks is expected to the best models for vehicle communications. This paper presents a video streaming on vehicle over WLAN and CDMA1X. The main objective is to evaluate the conditions and restrictions under which seamless continuity of video sessions across the two networks is feasible. First, it constructs high speed automobile communication environment by wireless access router which can automatically switched between CDMA1X and the WLAN. In order to fit the bandwidths sharply variety of wireless channel, adaptive video compression algorithms based MPEG4 is utilized to encode the high quality video. Moreover, unique transmission mechanism using media server and media gateway is presented, which can support large scale concurrent users up to 1000. This transmission mechanism uses the buffer on media server to smooth the video transport in wireless channel. The live streaming video of mobile can be viewed over Internet and does not need fix IP address. Therefore the networked vehicle can achieve seamless roaming and secured network connectivity anytime and anywhere.

关键词： Streaming media Vehicles IP networks Land mobile radio cellular systems Video compression Wireless LAN Web server Automobiles Wireless communication Communication switching

来源：评论

学校读者我要写书评

暂无评论

Multimodal detection of highlights for multimedia content

引用

multimedia systems 2004年第6期9卷 586-593页

作者： Dagtas, S Abdel-Mottaleb, M Univ Arkansas Dept Informat Sci Little Rock AR 72204 USA Univ Miami Dept Elect & Comp Engn Coral Gables FL 33146 USA

We present a multimedia information analysis framework for content-based browsing of video. Specifically, we develop algorithms for the automated extraction of video highlights in sports video that are based on audio, text, and image features. The extracted annotations are used to build applications for selective browsing of sports videos. Such summarization techniques enable content-based indexing of multimedia documents for efficient storage and retrieval. In addition, in the context of the newly emerging standard MPEG-7, these methods will enable applications that use MPEG-7 descriptions. As this standard provides only the syntax for representing such descriptions and not specific algorithms for extracting them, these algorithms are of great value for establishing MPEG-7 as an accepted standard. We provide experimental results for the proposed algorithms on several hours of sports programs that prove the feasibility of efficient video access techniques in a multimedia environment.

关键词： multimedia systems

来源：评论

学校读者我要写书评

暂无评论

Using MPEG standards for multimedia customization

引用

SIGNAL PROCESSING-IMAGE COMMUNICATION 2004年第5期19卷 437-456页

作者： Magalhaes, J Pereira, F Inst Super Engn Lisboa Lisbon Portugal Univ Tecn Lisboa Inst Telecomunicacoes Inst Super Tecn Lisbon Portugal

The multimedia content delivery chain poses today many challenges. The increasing terminal diversity, network heterogeneity and the pressure to satisfy the user preferences are raising the need for content to be customized in order to provide the user the best possible experience. This paper addresses the problem of multimedia customization by (1) presenting the MPEG-7 multimedia content description standard and the MPEG-21 multimedia framework;(2) classifying multimedia customization processing algorithms;(3) discussing multimedia customization systems;and (4) presenting some customization experiments. (C) 2004 Elsevier B.V. All rights reserved.

关键词： universal multimedia access multimedia custornization multimedia adaptation content description usage environment description MPEG-7 MPEG-21

来源：评论

学校读者我要写书评

暂无评论

Web access to large audiovisual assets based on user preferences

引用

multimedia TOOLS AND APPLICATIONS 2004年第3期22卷 215-234页

作者： Karpouzis, K Moschovitis, G Ntalianis, K Ioannou, S Kollias, S Natl Tech Univ Athens Dept Elect & Comp Engn Image Video & Multimedia Lab Athens 15780 Greece

Current multimedia databases contain a wealth of information in the form of audiovisual as well as text data. Even though efficient search algorithms have been developed for either media, there still exists the need for abstract presentation and summarization of the results of database users' queries. Moreover, multimedia retrieval systems should be capable of providing the user with additional information related to the specific subject of the query, as well as suggest other topics which could be identified to attract the interest of users with a similar profile. In this paper, we present solutions to these issues, giving as an example an integrated architecture we have developed, along with notions that support efficient and secure Internet access to audiovisual/video databases. Segmentation of each video in shots is followed by shot classification in a number of predetermined categories. Generation of users' profiles according to the categories, enhanced by relevance feedback, permits an efficient presentation of retrieved video shots or characteristic frames in terms of the user interest in them. Moreover, this clustering scheme assists the notion of 'lateral' links that enable the user to continue retrieval with data of similar nature or content to those already returned. Furthermore, user groups are formed and modeled by registering actual preferences and practices. This enables the system to 'predict' information that is possibly relevant to the user's interest and present it along with the returned results. The concepts utilized in this system can be smoothly integrated in MPEG-7 compatible multimedia database systems.

关键词： multimedia databases web access video summarization dynamic search user profiling query expansion

来源：评论

学校读者我要写书评

暂无评论

Knowledge-based media adaptation

Knowledge-based media adaptation

引用

conference on Internet multimedia Management systems V

作者： Leopold, K Jannach, D Hellwagner, H Univ Klagenfurt Dept Informat Technol Klagenfurt Austria

ISBN: (纸本)0819455547

This paper introduces the principal approach and describes the basic architecture and current implementation of the knowledge-based multimedia adaptation framework we are currently developing. The framework can be used in Universal multimedia access scenarios, where multimedia content has to be adapted to specific usage environment parameters (network and client device capabilities, user preferences). Using knowledge-based techniques (state-space planning), the framework automatically computes an adaptation plan, i.e., a sequence of media conversion operations, to transform the multimedia resources to meet the client's requirements or constraints. The system takes as input standards-compliant descriptions of the content (using MPEG-7 metadata) and of the target usage environment (using MPEG-21 Digital Item Adaptation metadata) to derive start and goal states for the planning process, respectively. Furthermore, declarative descriptions of the conversion operations (such as available via software library functions) enable existing adaptation algorithms to be invoked without requiring programming effort. A running example in the paper illustrates the descriptors and techniques employed by the knowledge-based media adaptation system.

关键词： multimedia adaptation adaptation decision taking metadata MPEG-7 MPEG-21

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：