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131.
网络灾害作为互联网给人类社会带来的各种潜在风险和负面效应之一,正在影响着社会各个行业。除了在网络安全技术、网络道德和相关法律等方面开展研究外,网络检测平台通过检测网络拓扑结构和其他网络动态属性,构建网络地图,可以为网络灾害的预防和控制提供相关依据。 相似文献
132.
在防灾项目中,给决策者提供精确的地质地理背景信息,使其随时查询各个地理信息要素是格外必要的,所以项目中的空间数据查询系统发挥着至关重要的作用;该项目中利用AECENGINE9.2的强大嵌入功能和良好的可操作性,基于visual studio 2005.NET使其功能在防灾项目中发挥出来,在地震地质和基础地理两大类中可详尽的查询出地壳等厚线、深断裂构造、遥感地质构造解译图等信息。 相似文献
133.
Long Lee 《Computers & Fluids》2010,39(6):1022-3253
We present a class of a high-resolution Godunov-type algorithms for solving flow problems governed by the incompressible Navier-Stokes equations. The algorithms use high-resolution finite volume methods developed in LeVeque (SIAM J Numer Anal 1996;33:627-665) for the advective terms and finite difference methods for the diffusion and the Poisson pressure equation. The high-resolution algorithm advects the cell-centered velocities using the divergence-free cell-edge velocities. The resulting cell-centered velocity is then updated by the solution of the Poisson equation. The algorithms are proven to be robust for constant-density flows at high Reynolds numbers via an example of lid-driven cavity flow. With a slight modification for the projection operator in the constant-density solvers, the algorithms also solve incompressible flows with finite-amplitude density variation. The strength of such algorithms is illustrated through problems like Rayleigh-Taylor instability and the Boussinesq equations for Rayleigh-Bénard convection. Numerical studies of the convergence and order of accuracy for the velocity field are provided. While simulations for two-dimensional regular-geometry problems are presented in this study, in principle, extension of the algorithms to three dimensions with complex geometry is feasible. 相似文献
134.
以气象水文信息显示系统软件开发为背景,针对风场流线分析与显示和温度对数压力图绘制功能的实现,提出了流线分析算法和温度对数压力图的不稳定能量区分析算法.流线分析算法从流线的基本概念出发,结合其物理连续分布的特征,基于风场格点u/v分量数据直接"跟踪"获得流线,并对过密、过短等情况进行了处理.温度对数压力图的不稳定能量区分析算法利用温压曲线与状态曲线的单调性,分段处理温压曲线与状态曲线的位置关系进行不稳定能量区分析.实际使用结果表明,2种算法均具有良好的显示效果和较高的处理效率. 相似文献
135.
136.
Abstract: Using a conjugate gradient method, a novel iterative support vector machine (FISVM) is proposed, which is capable of generating a new non‐linear classifier. We attempt to solve a modified primal problem of proximal support vector machine (PSVM) and show that the solution of the modified primal problem reduces to solving just a system of linear equations as opposed to a quadratic programming problem in SVM. This algorithm not only has no requirement for special optimization solvers, such as linear or quadratic programming tools, but also guarantees fast convergence. The full algorithm merely needs four lines of MATLAB codes, which gives results that are similar to or better than that of several new learning algorithms, in terms of classification accuracy. Besides, the proposed stand‐alone approach is capable of dealing with instability of classification performance of smooth support vector machine, generalized proximal support vector machine, PSVM and reduced support vector machine. Experiments carried out on UCI datasets show the effectiveness of our approach. 相似文献
137.
Sang‐Hee Ko Park Min‐Ki Ryu Sung‐Min Yoon Shinhyuk Yang Chi‐Sun Hwang Jae‐Hong Jeon 《Journal of the Society for Information Display》2010,18(10):779-788
Abstract— The stability of oxide TFTs has been the main focus of this research and is probably the most crucial requirement for the successful application to flat‐panel displays. Although the high Fermi level of oxide semiconductors makes TFTs basically stable under electrical stress, the device reliability under diverse variations of electrical stress is affected by materials such as active semiconductors and gate insulators, processes for the formation of back/front channels and passivation layers, and device configurations among other things. How these factors affect the device reliability have been investigated and a review of the stability is presented. In addition, several categories of the light instability of oxide TFTs is presented and the origin is discussed. 相似文献
138.
章萍芳 《数码设计:surface》2010,(5):23-24
21世纪是设计的世纪。人类文明发展到今天,设计已经超越原来的艺术或是技术范畴,而是作为现代文明各个方面的交汇点,开始"参与"这个世界。但是,与技术一样,设计本身也是双刃剑,既能给人类文明带来飞跃,也能为人类带来灾难。人类在享受设计成果的同时,更要警惕设计所带来的危机。 相似文献
139.
针对泥石流仿真过程中海量数据计算问题,采用CUDA技术即结合CPU与GPU的优点研究了一种协同计算方法以提高数据计算效率和仿真性能。同时,搭建了基于GPU的泥石流仿真计算平台,对优化的CUDA并行计算方法进行验证。实验结果表明,该方法对海量数据的计算具有快速准确、低成本、低功耗的特点,能为灾害预测提供及时准确的决策支持,满足了高密集型计算的需求。 相似文献
140.
Michael?DeBoleEmail author Ramakrishnan?Krishnan Varsha?Balakrishnan Wenping?Wang Hong?Luo Yu?Wang Yuan?Xie Yu?Cao N.?Vijaykrishnan 《International journal of parallel programming》2009,37(4):417-431
Degradation of device parameters over the lifetime of a system is emerging as a significant threat to system reliability.
Among the aging mechanisms, wearout resulting from Negative Bias Temperature Instability (NBTI) is of particular concern in
deep submicron technology generations. While there has been significant effort at the device and circuit level to model and
characterize the impact of NBTI, the analysis of NBTI’s impact at the architectural level is still at its infancy. To facilitate
architectural level aging analysis, a tool capable of evaluating NBTI vulnerabilities early in the design cycle has been developed
that evaluates timing degradation due to NBTI. The tool includes workload-based temperature and performance degradation analysis
across a variety of technologies and operating conditions, revealing a complex interplay between factors influencing NBTI
timing degradation. 相似文献