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151.
R. Lipton 《Journal of Optimization Theory and Applications》1994,81(3):549-568
The relaxation for optimal complicance design is independent of whether the underlying elastic problem is formulated in terms of displacements or strains. For the purposes of numerical experimentation and computation, it may be advantageous to formulate optimal design problems in terms of displacements as is done in Ref. 1. The relaxed problem delivered by the displacement-based formulation is of min-min-max type. Because of this, efficient numerical implementation is hampered by the order of the last two min-max operations. We show here that the last two min-max operations may be exchanged, facilitating an efficient numerical algorithm. We remark that the rigorous results given here corroborate the numerical methods and experiments given in Ref. 1.This work was supported by NSF Grant DMS-92-05158. 相似文献
152.
Reinhardt J. Heuer Robert Thayer Sataloff Kate Emerich Rhonda Rulnick Margaret Baroody Joseph R. Spiegel Gursel Durson John Butler 《Journal of voice》1997,11(1):88-94
This preliminary retrospective study of 19 female patients and 22male patients with unilateral recurrent nerve lesions demonstrated the promise of objective measurements in predicting the need for surgery, the efficacy of voice therapy in ameliorating vocal symptoms, and the effects of therapy in conjunction with surgery. Sixty-eight percent (68%) of the female patients and 64% of the male patients did not elect to have surgery. Outcome satisfaction of nonsurgical and surgical patients appeared to be similar. The data from this study support the importance of preoperative therapy for patients with unilateral vocal fold paralysis. 相似文献
153.
本文引进了H-值半鞅测度,研究了其基本性质和与之相联系的随机积分,本文还引入了H-值半鞅测度序列依分布弱收敛的概念,建立了H-值半鞅测度的极限定理,给出了H-值半鞅测度弱收敛的条件。 相似文献
154.
Certain path properties of a symmetric α-stable process X(t) = ∫Sh(t, s) dM(s), t T, are studied in terms of the kernel h. The existence of an appropriate modification of the kernel h enables one to use results from stable measures on Banach spaces in studying X. Bounds for the moments of the norm of sample paths of X are obtained. This yields definite bounds for the moments of a double α-stable integral. Also, necessary and sufficient conditions for the absolute continuity of sample paths of X are given. Along with the above stochastic integral representation of stable processes, the representation of stable random vectors due to[13], Ann. Probab.9, 624–632) is extensively used and the relationship between these two representations is discussed. 相似文献
155.
In this paper some of the aspects of implementing measures for quality assurance of e-learning in developing countries are discussed. Also the main problems of establishing quality assurance of e-learning are illustrated. The advantages of adopting international measures of quality assurance in those countries together with several recommendations for the future and our conclusion are then given. 相似文献
156.
《Operations Research Letters》2023,51(4):393-400
In this paper, we discuss an application of the Stochastic Dual Dynamic Programming (SDDP) type algorithm to nested risk-averse formulations of Stochastic Optimal Control (SOC) problems. We propose a construction of a statistical upper bound for the optimal value of risk-averse SOC problems. This outlines an approach to a solution of a long standing problem in that area of research. The bound holds for a large class of convex and monotone conditional risk mappings. Finally, we show the validity of the statistical upper bound to solve a real-life stochastic hydro-thermal planning problem. 相似文献
157.
Helio S. Migon Mariane Branco Alves André F. B. Menezes Eduardo G. Pinheiro 《商业与工业应用随机模型》2023,39(3):471-493
We briefly review the main developments of Bayesian dynamic models. The emphasis is on marketing applications. Typical examples in this area are discussed. The concepts of monitoring and intervention are carefully explained with illustrative examples and open source computational routines. We avoid algebraic developments and instead use graphical examples to illustrate theoretical aspects. Two real-world problems using Bayesian dynamic models are discussed. Finally, we describe recent developments and alternative proposals to formally address the dependence when dealing with the modeling of multiple time series. 相似文献
158.
文中就三峡永久船闸高边坡快速施工地质超前预报的几个问题进行了讨论。分别研究了三峡永久船闸高边坡施工地质超前预报的必要性,提出了超前预报技术思路,最后就高边坡岩体反分析及反馈设计问题、施工地质超前预报问题以及与监测相适应的超前处理及防护进行了分析。 相似文献
159.
下伏软弱层黄土边坡变形机制分析及治理对策研究 总被引:1,自引:0,他引:1
本文研究了陕北某电厂夹断层破碎带上覆黄土的泥岩、砂岩互层反倾边坡的变形机制,并研究治理对策及其治理效果。通过边坡工程地质条件及变形破坏特征分析,建立FLAC3D地质模型,采用数值模拟方法研究了边坡变形破坏机制,在此基础上提出削方减载、锚筋桩、锚杆及坡面防护的综合治理措施。研究结果表明,边坡的变形受开挖坡形的影响,坡体浅表层特别是断层带及坡顶黄土部位出现大范围拉应力集中,断层带出现向坡外的挤出变形,带动上部黄土的牵引式变形,引起沿黄土和基岩基覆界面的剪切变形,在黄土中出现大量拉裂缝,在一定条件下潜在滑移面逐渐贯通,坡体将产生整体失稳。边坡的治理应通过削方减载改善坡体应力环境,并重点控制断层带及黄土与基岩基覆界面的变形,数值模拟结果表明,治理后边坡稳定性较好,满足设计要求。 相似文献
160.