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531.
为提高图像配准算法的精度和适应能力,将超图约束和改进归一化互相关方法应用于图像配准。利用Hessian-Affine检测得到的仿射不变区域代替固定窗口来改进归一化互相关方法,获得初始匹配点对;通过马氏距离计算超边间的相似度,采用超图约束计算匹配分数对匹配对进行排序;利用分数高的部分匹配点对初始化变换矩阵,通过过滤匹配对来循环更新得到最优变换矩阵实现配准。实验结果表明,该方法具有较好的匹配和剔除错误匹配的效果,在不同类型的图像配准中也有较好的配准效果。  相似文献   
532.
We consider the problem of scheduling n independent and simultaneously available jobs without preemption on a single machine, where the machine has a fixed maintenance activity. The objective is to find the optimal job sequence to minimize the total amount of late work, where the late work of a job is the amount of processing of the job that is performed after its due date. We first discuss the approximability of the problem. We then develop two pseudo‐polynomial dynamic programming algorithms and a fully polynomial‐time approximation scheme for the problem. Finally, we conduct extensive numerical studies to evaluate the performance of the proposed algorithms. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 172–183, 2016  相似文献   
533.
We consider the problem of determining the capacity to assign to each arc in a given network, subject to uncertainty in the supply and/or demand of each node. This design problem underlies many real‐world applications, such as the design of power transmission and telecommunications networks. We first consider the case where a set of supply/demand scenarios are provided, and we must determine the minimum‐cost set of arc capacities such that a feasible flow exists for each scenario. We briefly review existing theoretical approaches to solving this problem and explore implementation strategies to reduce run times. With this as a foundation, our primary focus is on a chance‐constrained version of the problem in which α% of the scenarios must be feasible under the chosen capacity, where α is a user‐defined parameter and the specific scenarios to be satisfied are not predetermined. We describe an algorithm which utilizes a separation routine for identifying violated cut‐sets which can solve the problem to optimality, and we present computational results. We also present a novel greedy algorithm, our primary contribution, which can be used to solve for a high quality heuristic solution. We present computational analysis to evaluate the performance of our proposed approaches. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 236–246, 2016  相似文献   
534.
We present a validation of a centralized feedback control law for robotic or partially robotic water craft whose task is to defend a harbor from an intruding fleet of water craft. Our work was motivated by the need to provide harbor defenses against hostile, possibly suicidal intruders, preferably using unmanned craft to limit potential casualties. Our feedback control law is a sample‐data receding horizon control law, which requires the solution of a complex max‐min problem at the start of each sample time. In developing this control law, we had to deal with three challenges. The first was to develop a max‐min problem that captures realistically the nature of the defense‐intrusion game. The second was to ensure the solution of this max‐min problem can be accomplished in a small fraction of the sample time that would be needed to control a possibly fast moving craft. The third, to which this article is dedicated, was to validate the effectiveness of our control law first through computer simulations pitting a computer against a computer or a computer against a human, then through the use of model hovercraft in a laboratory, and finally on the Chesapeake Bay, using Yard Patrol boats. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 247–259, 2016  相似文献   
535.
ABSTRACT

China’s defense science, technology, and industrial system has been undergoing a far-reaching transformation over the past two decades and the single biggest factor behind this turnaround is the role of external technology and knowledge transfers and the defense industry’s improving ability to absorb these inputs and convert into localized output. China is pursuing an intensive campaign to obtain defense and dual-use civil–military foreign technology transfers using a wide variety of means, which is explored in this article.  相似文献   
536.
The warehouse problem with deterministic production cost, selling prices, and demand was introduced in the 1950s and there is a renewed interest recently due to its applications in energy storage and arbitrage. In this paper, we consider two extensions of the warehouse problem and develop efficient computational algorithms for finding their optimal solutions. First, we consider a model where the firm can invest in capacity expansion projects for the warehouse while simultaneously making production and sales decisions in each period. We show that this problem can be solved with a computational complexity that is linear in the product of the length of the planning horizon and the number of capacity expansion projects. We then consider a problem in which the firm can invest to improve production cost efficiency while simultaneously making production and sales decisions in each period. The resulting optimization problem is non‐convex with integer decision variables. We show that, under some mild conditions on the cost data, the problem can be solved in linear computational time. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 367–373, 2016  相似文献   
537.
The paper analyzes the effects of military spending on economic growth in a small open stochastic endogenous growth model involving the supply-side and demand-side effects produced by military spending. We show that a rise in the military spending affects economic growth through four channels, including the crowding-out effect, the spin-off effect, the resource mobilization effect, and the portfolio effect. The net effect which depends on these four channels is ambiguous. Hence, we demonstrate that there exists an optimal defense burden that maximizes the economic growth rate.  相似文献   
538.
聚类方法在污水处理软测量中的应用机理研究   总被引:1,自引:0,他引:1  
通过对污水处理过程建立多神经网络模型的可行性研究以及对活性污泥微生物的生长繁殖规律分析,得出在污水处理工程中采用基于聚类方法的多神经网络建模的理论依据,试验表明多神经网络的扩散常数同类半径相当接近,预测精度较高,证实了聚类分析的正确性.分析了可能影响模型精度的原因,指出采用在线实时算法是未来的研究方向.  相似文献   
539.
介绍了电磁装甲的种类、防护原理以及国内外的研究状况 ,阐明了电磁装甲的特点及其应用前景 ,最后提出了我国进行电磁装甲研究的思路  相似文献   
540.
空空协同作战指挥控制系统   总被引:3,自引:0,他引:3  
论述了研究与发展空空协同作战指挥系统的必要性 ,探讨了空空协同作战指挥系统的概念及系统的建模、结构模式 ,指挥决策的制定与优化、人机关系的处理、作战效能的评估与通讯共享集等几个问题  相似文献   
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