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31.
针对惯性平台自标定陀螺仪误差系数的可观测度问题,从可观性定义角度出发,提出一种可观测度分析方法。利用状态量解析解表达式中观测量导数的最高阶数定义该状态量的可观测度。在此基础上,研究惯性平台自标定系统可观性与陀螺仪误差系数可观测度,分析系统可观测的状态量及其可观测度,得出陀螺仪本轴一次项误差系数可观测度最差的结论。仿真结果验证了该方法的正确性和有效性,为惯性平台自标定中施矩方案的设计提供了理论依据。  相似文献   
32.
针对我校《实验化学》大循环教学模式的弊端,以信息技术与课堂教学的深度融合为契机,依托网络教学平台,构建了实验化学课程"一体化"体系.从多元化的学习型资源建设",问题反馈机制"的课堂",PST"模型的主体翻转学习空间",STES"理念教学等开展实验化学混合式教学改革,取得了较好的教学效果.  相似文献   
33.
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   
34.
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   
35.
提出了一种基于三对Bell态纠缠交换的量子确定性密钥分发方案(Quantum Deterministic Key Distribution,QDKD),该方案充分利用量子纠缠交换的原理,通过对三对Bell态进行纠缠、测量操作,并辅以经典信息实现确定性密钥的分发,方案中任何窃听行为都会被及时发现。同基于两对Bell态纠缠交换的QDKD方案相比,协议利用三对Bell态并使用两种方法实现确定性密钥信息的分发。分析结果表明,方案仅用到两粒子纠缠态,没有涉及任何幺正操作,操作性强,密钥分发效率高。  相似文献   
36.
全面系统地总结了目前声自导鱼雷上各种常用的导引方法,包括各种经典导引方法和各种基于现代控制理论设计的导引方法,分析了其优缺点,提出了在选择鱼雷导引方法时应考虑的因素,最后简要指出了其发展趋势,以便对声自导鱼雷的导引方法有个全面的认识,为鱼雷导引方法的改进和设计提供一定的参考。  相似文献   
37.
抗击临近空间高超声速飞行器对策研究   总被引:1,自引:0,他引:1  
在未来的空袭作战中,临近空间高超声速飞行器具有其他武器所不可比拟的优势,它必将成为一种新威胁。首先分析了该飞行器的卓越性能,简述了它的军事用途,其次论述了它的出现对防空反导体系所产生的影响,最后针对这种新型的威胁,提出了几点应对措施。  相似文献   
38.
Service systems such as call centers and hospital emergency rooms typically have strongly time‐varying arrival rates. Thus, a nonhomogeneous Poisson process (NHPP) is a natural model for the arrival process in a queueing model for performance analysis. Nevertheless, it is important to perform statistical tests with service system data to confirm that an NHPP is actually appropriate, as emphasized by Brown et al. [8]. They suggested a specific statistical test based on the Kolmogorov–Smirnov (KS) statistic after exploiting the conditional‐uniform (CU) property to transform the NHPP into a sequence of i.i.d. random variables uniformly distributed on [0,1] and then performing a logarithmic transformation of the data. We investigate why it is important to perform the final data transformation and consider what form it should take. We conduct extensive simulation experiments to study the power of these alternative statistical tests. We conclude that the general approach of Brown et al. [8] is excellent, but that an alternative data transformation proposed by Lewis [22], drawing upon Durbin [10], produces a test of an NHPP test with consistently greater power. We also conclude that the KS test after the CU transformation, without any additional data transformation, tends to be best to test against alternative hypotheses that primarily differ from an NHPP only through stochastic and time dependence. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 66–90, 2014  相似文献   
39.
We state a balancing problem for mixed model assembly lines with a paced moving conveyor as: Given the daily assembling sequence of the models, the tasks of each model, the precedence relations among the tasks, and the operations parameters of the assembly line, assign the tasks of the models to the workstations so as to minimize the total overload time. Several characteristics of the problem are investigated. A line‐balancing heuristic is proposed based on a lower bound of the total overload time. A practical procedure is provided for estimating the deviation of any given line‐balance solution from the theoretical optimum. Numerical examples are given to illustrate the methodology. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004.  相似文献   
40.
Extending Sastry's result on the uncapacitated two‐commodity network design problem, we completely characterize the optimal solution of the uncapacitated K‐commodity network design problem with zero flow costs for the case when K = 3. By solving a set of shortest‐path problems on related graphs, we show that the optimal solutions can be found in O(n3) time when K = 3, where n is the number of nodes in the network. The algorithm depends on identifying a list of “basic patterns”; the number of basic patterns grows exponentially with K. We also show that the uncapacitated K‐commodity network design problem can be solved in O(n3) time for general K if K is fixed; otherwise, the time for solving the problem is exponential. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004  相似文献   
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