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971.
半导体技术的发展以及系统芯片应用复杂度的不断增长,使得片上互连结构的吞吐量、功耗、信号完整性、延迟以及时钟同步等问题更加复杂,出现了以片上网络为核心的通信结构。由于系统芯片结构和片上通信的固有特性,从提高通信性能和降低硬件开销的角度进行层次化片上网络的设计对系统芯片的发展具有重要意义。本文提出了层次化的片上网络设计方法,根据实现工艺和应用需求,进行层次划分,产生若干个IP子集(将这个子集称为"簇"),按照簇间的通信需求进行片上网络的设计。实验表明,采用层次化的片上网络设计方法,能够有效提高系统性能,降低硬件实现的开销,同时满足一定的服务质量要求。 相似文献
972.
随着网络应用的不断发展,网络业务服务质量保证变得越来越重要,接入控制功能的实现为业务提供商给用户基于策略的流量限制提供了可能,更好地满足网络成本与业务服务等级之间的公平性,同时提高了网络的安全性。边缘设备接入控制的关键技术是在实现接入控制的同时保证数据转发处理的性能。本文基于边缘设备接入控制需求和接入控制策略表的特点,设计并分析了多种匹配算法,提出了接入控制策略实现中需考虑的关键因素。文章的最后给出了"接口 编号"链表式接入控制表的实现。该实现方法被应用国内驻地网边缘设备的接入控制,应用效果良好。 相似文献
973.
Based on Quick Bird satellite image data, the present study examined small-scale herbaceous community patches in the marsh of the Sanjiang Plain and measured patch characteristics such as the area, perimeter and shape by GPS. The coenological characteristics of the patches were investigated using quadrat method, and the vascular plant species were recorded using transect method. A total of 219 plant species were recorded, which represents 12.2% of the vascular flora in Heilongjiang Province. Our results showed that species number S correlated with patch area and perimeter; richness index (R) correlated with patch perimeter; Simpson index (D) correlated with patch area and perimeter/area; Shannon-Wiener index (H′) correlated with patch area, perimeter and perimeter/area; Evenness index (Jsw) correlated with perimeter/area. Both S and R have significant difference between different size of patches. Plant diversity in the small-scale herbaceous communities tended to increase with the patch area and perimeter. We concluded that edge effects and the habitat heterogeneity of the patches are important in determining the number of species. The relative smoothness of the patch edges also affects the plant diversity of the patches. The richness of plant species in the marsh in the Sanjiang Plain is highly sensitive to the small-scale patches, which continues to play an important role in preserving plant diversity in the local area. 相似文献
974.
Shao ji'an 《自然科学进展(英文版)》2007,(8)
Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 254 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic rocks.Compositions of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic. 相似文献
975.
Model Checking-Based Testing of Web Applications 总被引:1,自引:0,他引:1
ZENG Hongwei MIAO Huaikou 《武汉大学学报:自然科学英文版》2007,12(5):922-926
A formal model representing the navigation behavior of a Web application as the Kripke structure is proposed and an approach that applies model checking to test case generation is presented. The Object Relation Diagram as the object model is employed to describe the object structure of a Web application design and can be translated into the behavior model. A key problem of model checking-based test generation for a Web application is how to construct a set of trap properties that intend to cause the violations of model checking against the behavior model and output of counterexamples used to construct the test sequences. We give an algorithm that derives trap properties from the object model with respect to node and edge coverage criteria. 相似文献
976.
Thermal simulation experiment on the hydrocarbon regeneration of marine carbonate source rock 总被引:1,自引:0,他引:1
LI HuiLi JIN ZhiJun HE ZhiLiang QIN JianZhong SHAO ZhiBing 《科学通报(英文版)》2007,52(14):1992-1999
Hydrocarbon regeneration of marine carbonate source rock was simulated with thermal experiments in a laboratory. The results reveal that hydrocarbon regeneration does not simply continue the primary hydrocarbon generation process, and that, for marine carbonate source rock, discontinuous hydrocarbon generation differs greatly from the continuous generation. Several different features of hydrocarbon regeneration were observed in the experiments. First, the liquid hydrocarbon generation peak was always observed no matter what the initial maturity of the sample was. Moreover, the maturity and the liquid hydrocarbon yield corresponding to the peak varied with the sample’s initial maturity. Second, the hydrocarbon regeneration started earlier than the continuous one. In the experiments, the hydrocarbon could be re-generated when the sample maturity did not rise to any great extent. Third, the accumulative hydrocarbon-generating quantity during discontinuous generation was always more than that during continuous generation. And the hydrocarbon-generating quantity varied with the discontinuous generation history. Chemical kinetic analysis suggests that discontinuous hydrocarbon generation should not only be explained by the parallel reaction mechanism but also by the consecutive reaction mechanism which has been ignored in the traditional chemical kinetic model for continuous hydrocarbon generation. 相似文献
977.
比较了几种主要的Web开发技术,介绍一种基于Delphi5核心技术支持的分布式Web网站的开发方法,并给出了运用Delphi5的Web核心技术开发税法查询Web系统的一些细节。 相似文献
978.
支持并行工程的概念设计系统的开发与研究 总被引:4,自引:0,他引:4
提出将产品数据管理引入概念设计阶段的管理思想,详细讨论了实现的框架及其分解综合的流程,利用基于C/S模式的PDM技术及引入位于服务器端的DBMS作为公共的数据黑板,系统实现了用户管理、产品方案库的管理,并集成各领域专家的意见实现了协同设计。 相似文献
979.
研究无界区域上的一类广义耦合非线性波动方程组问题,利用Sobolev插值不等式和加权空间,对t做一致先验估计,得到整体解的存在性. 相似文献
980.