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91.
Quantitative performance modeling of complex information systems is of immense importance for designing enterprise e-business infrastructures and applications. In this paper, we present a traffic model of a server node in a typical transaction processing middleware system as well as a quantitative framework to model and analyze its performance. A multi-class open queueing network model is presented in which multi-class jobs are admitted to a number of server processes sharing hardware resources including the CPU and the disk. We have developed a viable approximation method, which decomposes the dependent components into their independent counterparts while preserving their relevant characteristics. We have conducted queueing-theoretic delay analyses and verified the approach using simulation. Results demonstrate the strength of our approach in predicting delays, elapsed times and other system performance measures. 相似文献
92.
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
93.
Scalability is a key factor of the design of distributed systems and parallel algorithms and machines. However, conventional scalabilities are designed for homogeneous parallel processing. There is no suitable and commonly accepted definition of scalability metric for heterogeneous systems. Isospeed scalability is a well-defined metric for homogeneous computing. This study extends the isospeed scalability metric to general heterogeneous computing systems. The proposed isospeed-efficiency model is suitable for both homogeneous and heterogeneous computing. Through theoretical analyses, we derive methodologies of scalability measurement and prediction for heterogeneous systems. Experimental results have verified the analytical results and confirmed that the proposed isospeed-efficiency scalability works well in both homogeneous and heterogeneous environments. 相似文献
94.
Haoqiang Jin Barbara Chapman Lei Huang Dieter an Mey Thomas Reichstein 《International journal of parallel programming》2008,36(3):312-325
We describe a performance study of a multi-zone application benchmark implemented in several OpenMP approaches that exploit
multi-level parallelism and deal with unbalanced workload. The multi-zone application was derived from the well-known NAS
Parallel Benchmarks (NPB) suite that involves flow solvers on collections of loosely coupled discretization meshes. Parallel
versions of this application have been developed using the Subteam concept and Workqueuing model as extensions to the current
OpenMP. We examine the performance impact of these extensions to OpenMP and compare with hybrid and nested OpenMP approaches
on several large parallel systems. 相似文献
95.
Aminollah Mahabadi Hamid Sarbazi-Azad Ebrahim Khodaie Keivan Navi 《The Journal of supercomputing》2008,45(1):1-14
This paper proposes an efficient parallel algorithm for computing Lagrange interpolation on k-ary n-cube networks. This is done using the fact that a k-ary n-cube can be decomposed into n link-disjoint Hamiltonian cycles. Using these n link-disjoint cycles, we interpolate Lagrange polynomial using full bandwidth of the employed network. Communication in the
main phase of the algorithm is based on an all-to-all broadcast algorithm on the n link-disjoint Hamiltonian cycles exploiting all network channels, and thus, resulting in high-efficiency in using network
resources. A performance evaluation of the proposed algorithm reveals an optimum speedup for a typical range of system parameters
used in current state-of-the-art implementations.
相似文献
Hamid Sarbazi-AzadEmail: Email: |
96.
Ke-Jun Jin Xiao-Fen Qin Jian Tan Yuan-Yuan Zhang 《Sensors and actuators. A, Physical》2008,147(1):34-40
The operating procedure of engine requires that the mass air flow (MAF) sensor can measure the pulsation air flow accurately. Therefore the MAF sensor must possess fast response speed. It is necessary to study the dynamic characteristic of the MAF sensor. Both the experimental equipments and method used by authors previously are improved to obtain the sensor response data accurately in this paper. The static and dynamic separable modeling method is adopted to build the uniform nonlinear dynamic model of the hot-film MAF sensor in the Hammerstein and Wiener forms, which can describe the large/small flow-rate and positive/negative step responses. The performance indexes are calculated by the actual and model responses. 相似文献
97.
It has been a common consensus that general techniques for stabilization of nonlinear systems are available only for some
special classes of nonlinear systems. Control design for nonlinear systems with uncertain components is usually carried out
on a per system basis, especially when physical control constraints, and certain control performance measures such as optimum
time control are imposed. Elegant adaptive control techniques are difficult to apply to this type of problems. A new neural
network based control design is proposed and presented in this paper to deal with a special class of uncertain nonlinear systems
with multiple inputs. The desired system dynamics are analyzed and utilized in the process of the proposed intelligent control
design. The theoretical results are provided to justify the design procedures. The simulation study is conducted on a second-order
bilinear system with two inputs and uncertainties on its parameters. The simulation results indicate that the proposed design
approach is effective. 相似文献
98.
首先介绍了工作流和工作流管理系统的定义,阐述了网格工作流和军事信息网格的研究现状.其次研究了网格工作流的调度模型并分析了网格工作流调度过程,通过将工作流的思想应用到军事信息网格系统中,给出了基于网格工作流的军事信息网格系统总体设计架构,并对架构中的各个组成模块进行了研究. 相似文献
99.
李震尧 《数字社区&智能家居》2009,(9)
在电子系统中经常需要用到稳定性好,工作效率高的电源。开关电源的可靠性高,不仅提高电子系统工作效率,而且使电子设备在维修和管理方面的费用降低。文章将主要介绍开关电源可靠性指标,分析影响可靠性的因素及提高系统可靠性的途径。 相似文献
100.
多机器人覆盖技术研究进展 总被引:4,自引:0,他引:4
系统地总结了当前覆盖问题的定义、分类和应用前景.对多机器人覆盖中关于通信、环境地图、路径规划算法及效果评价等方面的研究进展情况进行了阐述.分析并指出若干多机器人覆盖研究中的重点和难点问题:体系结构、通信技术、协商协作、地图表示、路径规划及效果评价,并对未来的研究发展方向进行了探讨. 相似文献