全文获取类型
收费全文 | 180篇 |
免费 | 47篇 |
国内免费 | 11篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 1篇 |
2019年 | 6篇 |
2018年 | 1篇 |
2017年 | 10篇 |
2016年 | 12篇 |
2015年 | 4篇 |
2014年 | 9篇 |
2013年 | 12篇 |
2012年 | 23篇 |
2011年 | 19篇 |
2010年 | 14篇 |
2009年 | 25篇 |
2008年 | 11篇 |
2007年 | 19篇 |
2006年 | 11篇 |
2005年 | 6篇 |
2004年 | 9篇 |
2003年 | 3篇 |
2002年 | 7篇 |
2001年 | 4篇 |
2000年 | 6篇 |
1999年 | 5篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1988年 | 1篇 |
排序方式: 共有238条查询结果,搜索用时 328 毫秒
141.
142.
143.
针对无线局域网环境及室内目标定位需求,研究了基于接收信号强度指示的定位技术,提出了一种基于多元高斯概率分布的信号强度模式匹配方法,讨论了定位系统框架。试验结果表明,该方法具有较好的室内定位效果。 相似文献
144.
提出了一种基于最小最大决策的三站时差定位布阵优化方法,以提高系统对目标区域的整体定位精度。应用基于最小最大决策的最优化理论,建立布阵优化问题的数学模型。该模型以三站坐标为决策变量,以目标区域的最大水平定位误差最小为目标函数,然后运用基于最小最大决策的最优化算法,求解模型的最优解,并将此最优解作为三站时差定位系统的最优布阵。仿真结果与理论计算一致,验证了这种布阵优化结果的最优性。 相似文献
145.
梁春香 《中国人民武装警察部队学院学报》2014,(1):6-10
在全球毒品问题继续蔓延的趋势下,海峡两岸跨境毒品犯罪愈演愈烈。要有效遏制毒品犯罪给海峡两岸社会治安带来的危害,海峡两岸的警察机关应不断完善跨境追逃合作机制、犯罪资产追缴协助机制、调查取证协助机制,健全毒品犯罪情报交流机制,构建区际“控制下交付”合作机制,逐步拓宽打击跨境毒品犯罪警务合作渠道,以有效遏制海峡两岸毒品犯罪的发展蔓延。 相似文献
146.
We study an infinite horizon periodic stochastic inventory system consisting of retail outlets and customers located on a homogenous line segment. In each period, the total demand, generated by the customers on the line, is normally distributed. To better match supply and demand, we incorporate lateral transshipments. We propose a compact model in which the strategic decisions—the number and locations of retail outlets—are determined simultaneously with the operational decisions—the inventory replenishment and transshipment quantities. We find the optimal balance between the risk‐pooling considerations, which drive down the optimal number of retail outlets, and lateral transshipments, which drive up the optimal number of retail outlets. We also explore the sensitivity of the optimal number of retail outlets to various problem parameters. This article presents a novel way of integrating lateral transshipments in the context of an inventory‐location model. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011 相似文献
147.
The Annealing Adaptive Search (AAS) algorithm for global optimization searches the solution space by sampling from a sequence of Boltzmann distributions. For a class of optimization problems, it has been shown that the complexity of AAS increases at most linearly in the problem dimension. However, despite its desirable property, sampling from a Boltzmann distribution at each iteration of the algorithm remains a practical challenge. Prior work to address this issue has focused on embedding Markov chain‐based sampling techniques within the AAS framework. In this article, based on ideas from the recent Cross‐Entropy method and Model Reference Adaptive Search, we propose an algorithm, called Model‐based Annealing Random Search (MARS), that complements prior work by sampling solutions from a sequence of surrogate distributions that iteratively approximate the target Boltzmann distributions. We establish a novel connection between MARS and the well‐known Stochastic Approximation method. By exploiting this connection, we prove the global convergence of MARS and characterize its asymptotic convergence rate behavior. Our empirical results indicate promising performance of the algorithm in comparison with some of the existing methods. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011 相似文献
148.
An equity model between groups of demand points is proposed. The set of demand points is divided into two or more groups. For example, rich and poor neighborhoods and urban and rural neighborhoods. We wish to provide equal service to the different groups by minimizing the deviation from equality among groups. The distance to the closest facility is a measure of the quality of service. Once the facilities are located, each demand point has a service distance. The objective function, to be minimized, is the sum of squares of differences between all pairs of service distances between demand points in different groups. The problem is analyzed and solution techniques are proposed for the location of a single facility in the plane. Computational experiments for problems with up to 10,000 demand points and rectilinear, Euclidean, or general ?p distances illustrate the efficiency of the proposed algorithm. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011 相似文献
149.
频差估计是无源定位系统中的关键部分,其估计精度直接决定了无源定位系统的性能。本文对单频脉冲信号频差估计误差方差的Cramer-Rao下限(CRLB)进行了理论分析研究。在建立数学模型的基础上,定量分析了频差估计误差CRLB与接收信号参数的数学关系。通过直接公式推导和数值仿真归纳,分别得出了相参/非相参单频脉冲信号频差估计误差CRLB的解析表达式,该结论可用于指导基于频差估计的无源定位系统设计。 相似文献
150.