As mobile devices get ubiquitous and grow in computational power, their management of interdependent data also becomes increasingly important. the mobile environment exhibits all the characteristics of a distributed d...
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ISBN:
(纸本)9781581134360
As mobile devices get ubiquitous and grow in computational power, their management of interdependent data also becomes increasingly important. the mobile environment exhibits all the characteristics of a distributed database plus the feature of whimsical connectivity. Consequently, transactions respecting data consistency can suffer unbounded and unpredictable delays at both mobile and stationary nodes. the currently popular multi-tier model, in which mobile devices are in one end and always-connected stationary servers in the other, has certain practical advantages. However, it assumes that all integrity constraints are evaluated at the servers and hence relies on the semantics of operations for any autonomy enhancement of the mobile devices. In this paper, we examine the idea of constraint localization in cases where two mobile nodes each own data that share a constraint. It relies on reformulation of a constraint into more flexible local constraints that give more autonomy to the mobile nodes. the scheme also involves dynamic changes of these local constraints through negotiation, which we call re-localization. To overcome the problem of simultaneous requests for such re-localization, we give algorithms along with experimental results indicating their effectiveness.
the fuzzy graph is used frequently as a method for the Sociogram analysis,. If we cannot draw an intelligible fuzzy graph, understanding the results of the analysis will become difficult. We show the method of display...
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the fuzzy graph is used frequently as a method for the Sociogram analysis,. If we cannot draw an intelligible fuzzy graph, understanding the results of the analysis will become difficult. We show the method of displaying a intelligible fuzzy graph automatically.
Although advanced and innovative technologies have been used to retrieve information, the need of advanced, new techniques for Web information retrieval is extant. One of the main difficulties is to return accurate in...
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Although advanced and innovative technologies have been used to retrieve information, the need of advanced, new techniques for Web information retrieval is extant. One of the main difficulties is to return accurate information that fully describes the human request. Standard Web search engines provide two mechanisms to handle a user's query: to input the search keywords or to restrict the searching within a certain topic. these approaches appear too weak to cope with such a vast amount of information and with such a rich human expressiveness. Our approach to Web information retrieval consists in merging different available technologies and paradigms: mobile computation is exploited as effective approach to obtain updated results by dispatching the agents directly on Web resources. Agents are equipped with deductive behavior so to be autonomous in applying inference-based reasoning. A similarity model is embedded into the reasoning engine in order to correctly process the approximation level established at user level side.
Abstract: Computational grids such as the Information Power Grid [1], Particle Physics Data Grid [2], and Earth System Grid [3] depend on TCP to provide reliable communication between nodes across a wide-area network ...
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Abstract: Computational grids such as the Information Power Grid [1], Particle Physics Data Grid [2], and Earth System Grid [3] depend on TCP to provide reliable communication between nodes across a wide-area network (WAN). Of the available TCP implementations, TCP Reno and its variants are the most widely deployed; however, Reno's performance in computational grids is mediocre at best. Due to conflicting results in the evaluation of TCP implementations [4,5,6,7,8,9,10,11,12,13], we present a detailed simulation study that unifies the conflicting results and demonstrates the limitations of earlier work. We focus on the two most debated versions of TCP - Reno and Vegas. Using real traffic distributions, we show that Vegas performs well over modern high-performance links and better than Reno withthe proper selection of the Vegas parameters alpha and beta. Our results exhibit ways to significantly enhance the performance of distributed computational grids that rely on TCP.
this paper reports the implementation of a multi-node dynamically reconfigurable computing system. the system is based on a scalable dynamic reconfigurable computing node which consists of three resource layers. Scala...
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To support parallel computing in a distributed object-based computing platform, a uniform high performance distributed object architecture layer is necessary. In this paper, we propose a distributed object-based frame...
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this paper describes a tool framework and techniques for combining serialisation and reconfiguration to produce efficient designs. Convolver and matrix multiplier designs are examined. Several optimisation techniques,...
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Mobile computing is becoming more and more pervasive, liberating users from the confines of wired networks. At the same time, transparent access to heterogeneous, distributed information sources has become a reality i...
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Mobile computing is becoming more and more pervasive, liberating users from the confines of wired networks. At the same time, transparent access to heterogeneous, distributed information sources has become a reality in wired computing. Obviously, this kind of access is highly desirable for mobile users, too. However, current architectures for transparent information access do not take the specific needs of mobile users into account, while existing architectures for mobile computing do not support transparent access well. For the future growth of the usage of mobile computing it is of utmost importance that instead of individually developed, isolated extensions to the existing architectures, the research community agrees on a strong, standardized middleware platform extending both existing mobile architectures and existing information access architectures to ensure mobile access in heterogeneous environments. In this paper we propose such a platform.
Requirements of providing the maximum gain, spatial resolution and minimum side lobe levels of antennas are contradictory. therefore the problem of antenna optimization by its integral characteristics arises. the inte...
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Requirements of providing the maximum gain, spatial resolution and minimum side lobe levels of antennas are contradictory. therefore the problem of antenna optimization by its integral characteristics arises. the integral characteristic describing the side and back radiation is the antenna scattering coefficient. the scattering coefficient determines the noise temperature. In this paper the authors discuss the computer optimization of cophasal antenna arrays.
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