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排序方式: 共有9350条查询结果,搜索用时 15 毫秒
71.
蔡国瑜 《计算机光盘软件与应用》2011,(17)
随着计算机技术的不断向前发展,云计算和云存储作为一种崭新的模式,愈发受到个人和企业的关注。本文在对云计算进行简要介绍的基础上,对云计算环境下的数据存储即云存储体进行了分析和研究,展示了云存储的巨大优势,并就制约云存储进一步发展的若干问题进行了讨论。 相似文献
72.
首先对分布式数据库查询执行代价模型进行分析,然后对直接连接中的连接运算的方法、连接关系的传输方法和执行场地等问题进行研究,并计算所有评估方法的执行代价,从中选择出最小执行代价的执行方法,最终确定了执行的场地、连接的方法和传输方法. 相似文献
73.
In this paper, we propose a distributed agent model that applies belief-desire-intention (BDI) reasoning and negotiation for addressing the linear assignment problem (LAP) collaboratively. In resource allocation, LAP is viewed as seeking a concurrent allocation of one different resource for every task to optimize a linear sum objective function. The proposed model provides a basic agent-based foundation needed for efficient resource allocation in a distributed environment. A distributed agent algorithm that has been developed based on the BDI negotiation model is examined both analytically and experimentally. To improve performance in terms of average negotiation speed and solution quality, two initialization heuristics and two different reasoning control strategies are applied, with the latter yielding different variants of the basic algorithm. Extensive simulations suggest that all the heuristic-algorithm combinations can produce a near optimal solution soon enough in some specific sense. The significance and applicability of the research work are also discussed. 相似文献
74.
75.
In the paper, the approximate controllability of linear abstract second-order infinite-dimensional dynamical systems is considered. It is proved using the frequency-domain method, that approximate controllability of second-order system can be verified by the approximate controllability conditions for the corresponding simplified first-order system. General results are then applied for approximate controllability investigation of a vibratory dynamical system modeling flexible mechanical structure. Some special cases are also considered. Moreover, remarks and comments on the relationships between different concepts of controllability are given. The paper extends earlier results on approximate controllability of second-order abstract dynamical systems. 相似文献
76.
In this paper, we describe an implementation of use in demonstrating the effectiveness of architectures for real-time multi-agent
systems. The implementation provides a simulation of a simplified RoboCup Search and Rescue environment, with unexpected events,
and includes a simulator for both a real-time operating system and a CPU. We present experimental evidence to demonstrate
the benefit of the implementation in the context of a particular hybrid architecture for multi-agent systems that allows certain
agents to remain fully autonomous, while others are fully controlled by a coordinating agent. In addition, we discuss the
value of the implementation for testing any models for the construction of real-time multi-agent systems and include a comparison
to related work.
相似文献
Robin CohenEmail: |
77.
This paper presents an efficient scheme maintaining a separator decomposition representation in dynamic trees using asymptotically optimal labels. In order to maintain the short labels, the scheme uses relatively low
message complexity. In particular, if the initial dynamic tree contains only the root, then the scheme incurs an O(log4
n) amortized message complexity per topology change, where n is the current number of vertices in the tree. As a separator decomposition is a fundamental decomposition of trees used
extensively as a component in many static graph algorithms, our dynamic scheme for separator decomposition may be used for
constructing dynamic versions to these algorithms. The paper then shows how to use our dynamic separator decomposition to
construct efficient labeling schemes on dynamic trees, using the same message complexity as our dynamic separator scheme.
Specifically, we construct efficient routing schemes on dynamic trees, for both the designer and the adversary port models,
which maintain optimal labels, up to a multiplicative factor of O(log log n). In addition, it is shown how to use our dynamic separator decomposition scheme to construct dynamic labeling schemes supporting
the ancestry and NCA relations using asymptotically optimal labels, as well as to extend a known result on dynamic distance
labeling schemes.
Supported in part at the Technion by an Aly Kaufman fellowship.
Supported in part by a grant from the Israel Science Foundation. 相似文献
78.
We present in this paper BP-QL, a novel query language for querying business processes. The BP-QL language is based on an intuitive model of business processes, an abstraction of the emerging BPEL (business process execution language) standard. It allows users to query business processes visually, in a manner very analogous to how such processes are typically specified, and can be employed in a distributed setting, where process components may be provided by distinct providers. 相似文献
79.
Yunfeng GuAuthor Vitae Azzedine BoukercheRegina B. AraujoAuthor Vitae 《Journal of Parallel and Distributed Computing》2008
Data distribution management (DDM) plays a key role in traffic control for large-scale distributed simulations. In recent years, several solutions have been devised to make DDM more efficient and adaptive to different traffic conditions. Examples of such systems include the region-based, fixed grid-based, and dynamic grid-based (DGB) schemes, as well as grid-filtered region-based and agent-based DDM schemes. However, less effort has been directed toward improving the processing performance of DDM techniques. This paper presents a novel DDM scheme called the adaptive dynamic grid-based (ADGB) scheme that optimizes DDM time through the analysis of matching performance. ADGB uses an advertising scheme in which information about the target cell involved in the process of matching subscribers to publishers is known in advance. An important concept known as the distribution rate (DR) is devised. The DR represents the relative processing load and communication load generated at each federate. The DR and the matching performance are used as part of the ADGB method to select, throughout the simulation, the devised advertisement scheme that achieves the maximum gain with acceptable network traffic overhead. If we assume the same worst case propagation delays, when the matching probability is high, the performance estimation of ADGB has shown that a maximum efficiency gain of 66% can be achieved over the DGB scheme. The novelty of the ADGB scheme is its focus on improving performance, an important (and often forgotten) goal of DDM strategies. 相似文献
80.
P. Morillo A. Bierbaum P. Hartling M. Fernández C. Cruz-Neira 《Journal of Parallel and Distributed Computing》2008
Cluster computing has become an essential issue for designing immersive visualization systems. This paradigm employs scalable clusters of commodity computers with much lower costs than would be possible with the high-end, shared memory computers that have been traditionally used for virtual reality purposes. This change in the design of virtual reality systems has caused some development environments oriented toward shared memory computing to require modifications to their internal architectures in order to support cluster computing. This is the case of VR Juggler, which is considered one of the most important virtual reality application development frameworks based on open source code. 相似文献