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141.
传统的多河流串流计算主要采用水库联调的方法,把串流的各条河流概化为静态水库,库水位水平且不考虑横向流动。为解决串流区水流的横向流动及水面线并不总像库水位一样水平的问题,采用二维非恒定流数学模型计算串流区洪水演进。通过概化地形、考虑入流、糙率、边界条件和水流的横向流动等因素,计算出了整个串流区域的水面线、水深、流速、出流等水力要素,并给出洪水演进模拟图,为确定河流与总干渠交叉建筑物的规模、总干渠左岸沿线水面线和对沿线村庄、农田的防洪影响提供了可靠的依据。 相似文献
142.
Maria Kelly Venezuela Mônica Carneiro SandovalDenise Aparecida Botter 《Computational statistics & data analysis》2011,55(4):1867-1883
Local influence diagnostics based on estimating equations as the role of a gradient vector derived from any fit function are developed for repeated measures regression analysis. Our proposal generalizes tools used in other studies (
[Cook, 1986] and [Cadigan and Farrell, 2002]), considering herein local influence diagnostics for a statistical model where estimation involves an estimating equation in which all observations are not necessarily independent of each other. Moreover, the measures of local influence are illustrated with some simulated data sets to assess influential observations. Applications using real data are presented. 相似文献
143.
Zhong C Zhuo Y Xia J Hu S Li C Jiang Z Wang S 《Computer methods and programs in biomedicine》2011,101(3):282-296
The reinforced urn processes (RUPs) approach can estimate the target dose on the basis of the prior distribution function precisely and conveniently without the requirements about the explicit-estimated dose-response curve and the posterior complicated inference. The application of the RUPs approach was not discussed from the perspective of phase I clinical trial in the previous studies which just focused on the theory and methodology. And the modification of the traditional RUPs design should be considered for the purposes of ethnics and efficiency. A SAS macro was designed to explore the appropriate parameter settings according to the simulation outcomes in different situations and apply the RUPs approach for two state processes in phase I clinical trail with the modified RUPs design. The posterior estimation can be obtained precisely and efficiently with application of SAS program following the appropriate workflow and determination rule which were described in the example. 相似文献
144.
In this paper, we investigate the positive influence dominating set (PIDS) which has applications in social networks. We prove that PIDS is APX-hard and propose a greedy algorithm with an approximation ratio of H(δ) where H is the harmonic function and δ is the maximum vertex degree of the graph representing a social network. 相似文献
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147.
基于机构矩阵型式运动学方程和速度加速度统一模型,讨论了机构运动影响系数通用
计算公式的结构和自动构造算法,得出的一组运动影响系数统一计算公式具有普遍的意义,
并可以方便地由计算机程序自动构造并求解.本文内容建立了机构速度及加速度分析和动力
学自动分析的基础,为通用计算机辅助分析系统的研制创造了先决条件. 相似文献
148.
Bounded Model Checking Using Satisfiability Solving 总被引:10,自引:1,他引:9
Edmund Clarke Armin Biere Richard Raimi Yunshan Zhu 《Formal Methods in System Design》2001,19(1):7-34
The phrase model checking refers to algorithms for exploring the state space of a transition system to determine if it obeys a specification of its intended behavior. These algorithms can perform exhaustive verification in a highly automatic manner, and, thus, have attracted much interest in industry. Model checking programs are now being commercially marketed. However, model checking has been held back by the state explosion problem, which is the problem that the number of states in a system grows exponentially in the number of system components. Much research has been devoted to ameliorating this problem.In this tutorial, we first give a brief overview of the history of model checking to date, and then focus on recent techniques that combine model checking with satisfiability solving. These techniques, known as bounded model checking, do a very fast exploration of the state space, and for some types of problems seem to offer large performance improvements over previous approaches. We review experiments with bounded model checking on both public domain and industrial designs, and propose a methodology for applying the technique in industry for invariance checking. We then summarize the pros and cons of this new technology and discuss future research efforts to extend its capabilities. 相似文献
149.
Gediminas Adomavicius Jesse C. Bockstedt Alok Gupta Robert J. Kauffman 《Information Technology and Management》2007,8(2):185-202
We propose a new conceptual model for understanding technology evolution that highlights dynamic and highly interdependent
relationships among multiple technologies. We argue that, instead of considering technologies in isolation, technology evolution
is best viewed as a dynamic system or ecosystem that includes a variety of interrelated technologies. By considering the interdependent nature of technology evolution, we
identify three roles that technologies play within a technology ecosystem. These roles are components, products and applications, and support and infrastructure. Technologies within an ecosystem interact through these roles and impact each others’ evolution. We also classify types
of interactions between technology roles, which we term paths of influence. We demonstrate the use of our proposed model through examples of wireless networking (Wi-Fi) technologies and a business
mini-case on the digital music industry.
相似文献
Robert J. KauffmanEmail: |
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