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31.
Sungil Kim Heeyoung Kim Jye‐Chyi Lu Michael J. Casciato Martha A. Grover Dennis W. Hess Richard W. Lu Xin Wang 《海军后勤学研究》2015,62(2):127-142
In the field of nanofabrication, engineers often face unique challenges in resource‐limited experimental budgets, the sensitive nature of process behavior with respect to controllable variables, and highly demanding tolerance requirements. To effectively overcome these challenges, this article proposes a methodology for a sequential design of experiments through batches of experimental runs, aptly named Layers of Experiments with Adaptive Combined Design (LoE/ACD). In higher layers, where process behavior is less understood, experimental regions cover more design space and data points are more spread out. In lower layers, experimental regions are more focused to improve understanding of process sensitivities in a local, data‐rich environment. The experimental design is a combination of a space‐filling and an optimal design with a tuning parameter that is dependent on the amount of information accumulated over the various layers. The proposed LoE/ACD method is applied to optimize a carbon dioxide (epet‐CO2) assisted deposition process for fabricating silver nanoparticles with pressure and temperature variables. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 127–142, 2015 相似文献
32.
We consider the problem of scheduling a set of n jobs on a single batch machine, where several jobs can be processed simultaneously. Each job j has a processing time pj and a size sj. All jobs are available for processing at time 0. The batch machine has a capacity D. Several jobs can be batched together and processed simultaneously, provided that the total size of the jobs in the batch does not exceed D. The processing time of a batch is the largest processing time among all jobs in the batch. There is a single vehicle available for delivery of the finished products to the customer, and the vehicle has capacity K. We assume that K = rD, where and r is an integer. The travel time of the vehicle is T; that is, T is the time from the manufacturer to the customer. Our goal is to find a schedule of the jobs and a delivery plan so that the service span is minimized, where the service span is the time that the last job is delivered to the customer. We show that if the jobs have identical sizes, then we can find a schedule and delivery plan in time such that the service span is minimum. If the jobs have identical processing times, then we can find a schedule and delivery plan in time such that the service span is asymptotically at most 11/9 times the optimal service span. When the jobs have arbitrary processing times and arbitrary sizes, then we can find a schedule and delivery plan in time such that the service span is asymptotically at most twice the optimal service span. We also derive upper bounds of the absolute worst‐case ratios in both cases. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 470–482, 2015 相似文献
33.
基于ABAQUS有限元软件,采用主从接触算法模拟桩-土相互作用、修正剑桥模型作为土体本构模型,通过在桩顶施加竖向位移荷载以及合适的网格划分技术建立了较为符合压入管桩压桩实际的有限元模型。利用得到的有限元模型模拟了压入管桩压桩产生的挤土位移场,对不同泊松比时压入管桩单桩挤土位移场进行了对比分析。结果表明:不同泊松比时竖向和水平挤土位移场沿深度方向和径向的分布规律趋于一致;土体泊松比的变化会对压入管桩压桩产生的竖向和水平挤土位移场产生较大影响;泊松比越大,压桩产生的竖向和水平挤土位移越大。 相似文献
34.
We consider the problem of identifying the simulated system with the best expected performance measure when the number of alternatives is finite and small (often < 500). Recently, more research efforts in the simulation community have been directed to develop ranking and selection (R&S) procedures capable of exploiting variance reduction techniques (especially the control variates). In this article, we propose new R&S procedures that can jointly use control variates and correlation induction techniques (including antithetic variates and Latin hypercube sampling). Empirical results and a realistic illustration show that the proposed procedures outperform the conventional procedures using sample means or control variates alone. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012 相似文献
35.
陈东青 《军械工程学院学报》1999,(1)
设Z是一致光滑Banach空间,T:X→X是次连续强增生算子,{an}、{βn}是两个实数列且满足0≤an≤1,及an→0(n→∞),令Mann迭代序列{Xn}定义为证明了迭代序列{xn}强收敛于S的不动点q的充要条件是||Txn||有界。 相似文献
36.
研究了形如X'(t)∈-Ax(t)+F(t,x(t)),0≤t≤T,X(0)=x0的微分包含解的存在的局部性和整体性的结果,并在某种条件下研究了解的稳定性。 相似文献
37.
网络图式军用文书是战时通用装备保障文书中通常采用的文书形式之一,给出装备保障文书辅助生成系统的总体结构,将网络分析方法引入通用装备保障文书辅助生成系统的研究,在此基础上阐述了网络图式文书生成子系统的功能、数学模型及网络计算、网络优化的部分算法。 相似文献
38.
39.
电子战仿真系统中防空武器作战效能研究 总被引:6,自引:1,他引:6
介绍了电子战仿真系统总体结构,研究了空中拦截、地对空导弹及高炮等模块的作战效能模型,并用Monte Carlo 试验方法分析了系统的电子对抗作战效能 相似文献
40.
夹杂物对有机涂层下碳钢腐蚀初期过程的影响 总被引:1,自引:0,他引:1
选择两种具有典型夹杂物的碳钢,通过浸泡试验,研究有机涂层下碳钢的腐蚀初期过程,并和裸钢的腐蚀过程进行对比.结果表明:涂层试样和裸钢试样腐蚀发展的初期过程都是点蚀;涂层试样点蚀诱发孕育期大大长于裸钢试样;点蚀的主要诱发源是钢中的硫化物和硅酸盐;硫化物夹杂物诱发点蚀及点蚀的扩展主要沿夹杂物与基体间的相界进行. 相似文献