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通过研究Win98系统注册表有关网卡配置子项的规范,利用BIOS的INT1A中断读取网卡的供应商ID及设备ID.等硬件参数,系统可自动修改无盘Win98工作站的有关网卡配置的注册表子项,使无盘站启动时,能正确加载网卡驱动,即使网络中不同工作站采用的网卡及其它计算机硬件完全不同,也可以直接启动无盘站,实现了真正的无盘PNP安装,方便了无盘Win98系统的安装设置,扩展了无盘Win98的应用范围。 相似文献
64.
Approaches for dealing with scheduling and load-balancing in PC-based cluster systems are famous and well known. In such environments, Self-Scheduling Schemes are suitable for parallel loops with independent iterations. However, while schemes such as FSS, GSS, and TSS fit most computer systems, they cannot provide good load-balancing. Chao-Tung Yang and Shun-Chi Chang proposed a parallel loop scheduling scheme for heterogeneous PC cluster systems in Yang and Chang [13]. Though the proposed scheme allows users to choose parameters before execution initialization, weaknesses in it motivated us to develop further improvements. For instance, using fixed and monotonous parameters can easily lead to invalid scheduling due to use of previously input information. Thus, in this paper we propose a new scheme that fits most widely available computer systems and allows the scheduling parameter to be adjusted dynamically in order to provide higher overall performance. 相似文献
65.
This article focuses on the effect of both process topology and load balancing on various programming models for SMP clusters
and iterative algorithms. More specifically, we consider nested loop algorithms with constant flow dependencies, that can
be parallelized on SMP clusters with the aid of the tiling transformation. We investigate three parallel programming models,
namely a popular message passing monolithic parallel implementation, as well as two hybrid ones, that employ both message
passing and multi-threading. We conclude that the selection of an appropriate mapping topology for the mesh of processes has
a significant effect on the overall performance, and provide an algorithm for the specification of such an efficient topology
according to the iteration space and data dependencies of the algorithm. We also propose static load balancing techniques
for the computation distribution between threads, that diminish the disadvantage of the master thread assuming all inter-process
communication due to limitations often imposed by the message passing library. Both improvements are implemented as compile-time
optimizations and are further experimentally evaluated. An overall comparison of the above parallel programming styles on
SMP clusters based on micro-kernel experimental evaluation is further provided, as well. 相似文献
66.
In this paper, we address the server selection problem for streaming applications on the Internet. The architecture we consider is similar to the content distribution networks consisting of geographically dispersed servers and user populations over an interconnected set of metropolitan areas. Server selection issues for Web-based applications in such an environment have been widely addressed; the selection is mostly based on proximity measured using packet delay. Such a greedy or heuristic approach to server selection will not address the capacity planning problem evident in multimedia applications. For such applications, admission control becomes an essential part of their design to maintain Quality of Service (QoS). Our objective in providing a solution to the server selection problem is threefold: first, to direct clients to the nearest server; second, to provide multiple sources to diffuse network load; third, to match server capacity to user demand so that optimal blocking performance can be expected. We accomplish all three objectives by using a special type of Linear Programming (LP) formulation called the Transportation Problem (TP). The objective function in the TP is to minimize the cost of serving a video request from user population x using server y as measured by network distance. The optimal allocation between servers and user populations from TP results in server clusters, the aggregated capacity of each cluster designed to meet the demands of its designated user population. Within a server cluster, we propose streaming protocols for request handling that will result in a balanced load. We implement threshold-based admission control in individual servers within a cluster to enforce the fair share of the server resource to its designated user population. The blocking performance is used as a trigger to find new optimal allocations when blocking rates become unacceptable due to change in user demands. We substantiate the analytical model with an extensive simulation for analyzing the performance of the proposed clustered architecture and the protocols. The simulation results show significant difference in overall blocking performance between optimal and suboptimal allocations in as much as 15% at moderate to high workloads. We also show that the proposed cluster protocols result in lower packet loss and latencies by forcing path diversity from multiple sources for request delivery. 相似文献
67.
A method is proposed for use in summarization of text-based documents. By means of the method it is possible to discover latent topical sections and information-rich sentences. The underlying basis of the method — clustering of sentences — is formulated mathematically in the form of a problem of quadratic-type integer programming. An algorithm that makes it possible to determine with specified precision the optimal number of clusters is developed. The synthesis of a neural network is described for the purpose of solving a problem of integer quadratic programming. 相似文献
68.
The test statistics Ih, Ic, and In are derived by decomposing the numerator of the Moran's I test for high-value clustering, low-value clustering, and negative autocorrelation, respectively. Formulae to compute the means and variances of these test statistics are derived under a random permutation test scheme, and the p-values of the test statistics are computed by asymptotic normality. A set of simulations shows that test statistic Ih is likely to be significant only for high-value clustering, test statistic Ic is likely to be significant only for low-value clustering, and test statistic In is likely to be significant only for negatively correlated spatial structures. These test statistics were used to reexamine spatial distributions of sudden infant death syndrome in North Carolina and the pH values of streams in the Great Smoky Mountains. In both analyses, low-value clustering and high-value clustering were shown to exit simultaneously. 相似文献
69.
This paper explores the role of distant knowledge links and policy actions for the development of biotechnology clusters. It seeks to challenge the prevailing view that the birth and early development of high technology industries are always spontaneous phenomena which are mainly based on local knowledge. Departing from the theoretical concept of regional innovation systems (RIS), a distinction between “RIS with strong potentials for high technology industries” and “RIS with weak potentials for high technology industries” will be drawn. It will be argued that in the latter case the development of biotechnology clusters is more dependent on distant knowledge sources and proactive policy efforts to create a favourable environment for high technology activities. Furthermore, it will be shown that a far-reaching transformation of the regional innovation system is crucial for catching-up processes of regions which are latecomers in high technology sectors such as biotechnology. 相似文献
70.
针对模糊C-均值聚类算法偏好发现球形簇,以及对孤立点非常敏感的问题,提出了密集簇中心二次模糊聚类算法,其中引入聚类有效性度量函数,并进行了有效的孤立点处理,最终的模糊簇由多个代表点共同表示,故算法可有效发现数据集中的自然簇数目,对簇的大小和形状没有偏好性,且在孤立点的处理上具有较好的健壮性.另外,随机采样过程方便地实现了上述算法在大型数据集上的扩展;与模糊C-均值聚类算法的实验结果比较也表明了该算法的优越性. 相似文献