Efficient file searching is an essential feature in P2P systems. While many current approaches use brute force techniques to search files by meta information (file names, extensions or user-provided tags), the interes...
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Efficient file searching is an essential feature in P2P systems. While many current approaches use brute force techniques to search files by meta information (file names, extensions or user-provided tags), the interest is in implementing techniques that allow content-based search in P2P systems. Recently, clustering techniques have been used for searching text documents to increase the efficiency of document discovery and retrieval. Integrating such techniques into P2P systems is important to enhance searching in P2P file sharing systems. While some effort has been taken for content-based searching for text documents in P2P systems, there has been few research work for applying these techniques to multimediacontent in P2P systems. In this paper, we introduce two P2P content-based clustering techniques for multimedia documents. These techniques are an adaptation of the existing Class-based Semantic Search algorithm for text documents. The proposed algorithms have been integrated into a JXTA-based Overlay P2P platform, and evaluation results are provided. The JXTA-Overlay together with the considered clustering techniques is thus very useful for developing P2P multimedia applications requiring efficient searching of multimediacontents in peer nodes.
We have built an HTTP based resource discovery system called Discover that provides a single point of access to over 500 WAIS servers. Discover provides two key services: query refinement and query routing. Query refi...
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We have built an HTTP based resource discovery system called Discover that provides a single point of access to over 500 WAIS servers. Discover provides two key services: query refinement and query routing. Query refinement helps a user improve a query fragment to describe the user's interests more precisely. Once a query has been refined and describes a manageable result set, query routing automatically forwards the query to the WAIS servers that contain relevant documents. Abbreviated descriptions of WAIS sites called content labels are used by the query refinement and query routing algorithms. Our experimental results suggest that query refinement in conjunction with the query routing provides an effective way to discover resources in a large universe of documents. Our experience with query refinement has convinced us that the expansion of query fragments is essential in helping one use a large, dynamically changing, heterogenous distributed information system.
This paper describes content, a practical, scalable, and high performance text-indexed multimedia database system. The novelty of content is in its approach of integrating high-volume storage, fast searching and brows...
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ISBN:
(纸本)0897918681
This paper describes content, a practical, scalable, and high performance text-indexed multimedia database system. The novelty of content is in its approach of integrating high-volume storage, fast searching and browsing, easy multimedia acquisition, effective updates, scalability, extendibility, and an API based on HTTP. content is also a low-cost solution for large multimedia databases that is available today. Standard Web-based browsers such as Netscape can query the content server. The API is flexible so that different and unique content clients on multiple platforms can be built to access multiple content servers. The content architecture permits any multimedia type to be stored. Text descriptions are used as indices for images and videos. content includes an easy-to-use Windows-based acquisition station for acquiring images and video. Currently, content is being used in a real library setting and contains more than 25,000 multimedia objects that span two different collections of valuable historical photographs. In terms of performance, content can access a single image in a database of over one million images in less than a second.
This paper describes two protocols for the secure download of content protection software to mobile devices. The protocols apply concepts from trusted computing to demonstrate that a platform is in a sufficiently trus...
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ISBN:
(纸本)0769522734
This paper describes two protocols for the secure download of content protection software to mobile devices. The protocols apply concepts from trusted computing to demonstrate that a platform is in a sufficiently trustworthy state before any application or associated keys are securely downloaded The protocols are designed to allow mobile devices to receive broadcast content protected by proprietary conditional access applications. They may also be applied in the general case where demonstration of a secure execution environment is required before an application is downloaded.
In this paper we describe music retrieval in ICOR (Intelligent content Retrieval), a project of Darmstadt TU. It is the goal of ICOR to find new interfaces to support applications of music video and music CDs. Althoug...
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ISBN:
(纸本)0819434396
In this paper we describe music retrieval in ICOR (Intelligent content Retrieval), a project of Darmstadt TU. It is the goal of ICOR to find new interfaces to support applications of music video and music CDs. Although the project consists of audio and video analysis we concentrate on a description of the audio algorithms in this paper. We describe our MPEG-7 like data structure to store meta information for music pieces and explain which algorithms we use to analyze the content of music pieces automatically. We currently use an applause detection to distinguish live music from studio recordings, a genre classifier to distinguish pieces with beats (for example disco music) from classical music, and a singer recognition.
Power control in direct sequence-coded vision multiple access (DS-CDMA) systems and, more recently, power/rate allocation in multirate DS-CDMA based networks is an open and interesting research area which has attracte...
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Power control in direct sequence-coded vision multiple access (DS-CDMA) systems and, more recently, power/rate allocation in multirate DS-CDMA based networks is an open and interesting research area which has attracted much attention. However, with a few exceptions, most researchers have emphasized centralized resource allocation algorithms for cellular systems where the base station keeps track of the requirements of the various users and is thus responsible for the management of network resources. Ad hoc wireless local area networks (WLAN's), on the other hand, are generally configured as peer-to-peer networks with no centralized hub or controller. Thus resource allocation has to be conducted in a distributed fashion. We address the issue of distributed resource management for multirate DS-CDMA based multimedia WLAN's by 1) presenting a distributed resource allocation protocol, known as distributed resource negotiation protocol (DRNP) that builds on the RTS/CTS bandwidth reservation mechanism provided by IEEE 802.111, and provides quality of service (QoS) guarantees through distributed control of resources in DS-CDMA based multimedia WLAN's and 2) investigating the performance of various resource allocation schemes within the context of DRNP, in terms of network wide metrics such as overall throughput and blocking rates.
We consider in this paper downlink scheduling at the Medium access Layer (MAC) layer for delay sensitive traffic in wireless systems based on Orthogonal Frequency Division Multiple access (OFDMA). We refer in particul...
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ISBN:
(纸本)9781467304375;9781467304368
We consider in this paper downlink scheduling at the Medium access Layer (MAC) layer for delay sensitive traffic in wireless systems based on Orthogonal Frequency Division Multiple access (OFDMA). We refer in particular to next generation wireless systems such as 3GPP-LTE. We propose an Opportunistic Packet Loss Fair (OPLF) scheduling algorithm based on calculating a simple dynamic priority function which depends on the Head of Line (HOL) packet delay, the packet loss rate (PLR) and the achievable instantaneous downlink rate of each user. This algorithm overcomes the main limitations of existing algorithms, achieving better performance than state-of-the art algorithms, such as Modified Largest Weighted Delay First (M-LWDF), Proportional Fair (PF), and Packet Loss Fair (PLF), in terms of throughput, PLR and fairness among users.
When speaking of wireless and mobile Internet, we often assume that a bi-directional access network must be within reach. Usually we see GPRS, UMTS and wireless LANs as carriers supporting the Internet access service....
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ISBN:
(纸本)0780376617
When speaking of wireless and mobile Internet, we often assume that a bi-directional access network must be within reach. Usually we see GPRS, UMTS and wireless LANs as carriers supporting the Internet access service. This service consequently provides a basis for browsing and retrieving a wealth of digital multimediacontent upon user request. However, there are alternative means to deliver digital content to mobile users. Indeed, general content and content formats are independent from various communication methods. In this paper we focus on an alternative content delivery method - content push over terrestrial IP data broadcasting. To give a concrete context for discussion we assume DVB-T as transmission technology. The unidirectional, wide-band, shared channel suits especially well delivery service that targets multiple end users on the move. Applied to mobile communications, IP data broadcasting proves to complement the traditional mobile Internet access service provided over bi-directional accesssystems. From the viewpoint of international standards developing organizations, we tackle the issues needed to establish a globally inter-operable IP datacast baseline as a service platform.
Distributed multimedia Database systems (DMDB) have gained in popularity for today's database system design due to their fault-tolerance, resource-sharing capacity, and reliable performance. Reliability performanc...
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Distributed multimedia Database systems (DMDB) have gained in popularity for today's database system design due to their fault-tolerance, resource-sharing capacity, and reliable performance. Reliability performance is an important issue in DMDB design. The reliability of a DMDB depends on the reliability of its communication links and nodes as well as the distribution of its resources, such as various media. The distribution of media is an important factor that affect the multimedia query and access reliability (MQAR). The reliability-oriented media assignment problem is to find a media distribution such that the MQAR is maximal. In this paper, we attempt to develop a reliability model and algorithms to achieve reliability-oriented media allocation.
Template Detection algorithms use collections of web documents to determine the structure of a common underlying template. content Extraction algorithms instead operate on a single document and use heuristics to deter...
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ISBN:
(纸本)9780889867277
Template Detection algorithms use collections of web documents to determine the structure of a common underlying template. content Extraction algorithms instead operate on a single document and use heuristics to determine the main content. In this paper we propose a way to combine the reliability and theoretic underpinning of the first world with the single document based approach of the latter. Starting from a single initial documentwe use the set of hyperlinked web pages to build the required training set for Template Detection automatically. By clustering the documents in this set according to their underlying templates we clean the training set from documents based on different templates. We confirm the applicability of the approach by using an entropy based Template Detection algorithm to build a content Extractor.
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