全文获取类型
收费全文 | 255篇 |
免费 | 71篇 |
国内免费 | 10篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 6篇 |
2020年 | 4篇 |
2019年 | 6篇 |
2018年 | 2篇 |
2017年 | 17篇 |
2016年 | 18篇 |
2015年 | 9篇 |
2014年 | 22篇 |
2013年 | 14篇 |
2012年 | 10篇 |
2011年 | 19篇 |
2010年 | 15篇 |
2009年 | 20篇 |
2008年 | 15篇 |
2007年 | 14篇 |
2006年 | 14篇 |
2005年 | 16篇 |
2004年 | 15篇 |
2003年 | 13篇 |
2002年 | 12篇 |
2001年 | 11篇 |
2000年 | 12篇 |
1999年 | 11篇 |
1998年 | 3篇 |
1997年 | 4篇 |
1996年 | 7篇 |
1995年 | 4篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
排序方式: 共有336条查询结果,搜索用时 281 毫秒
241.
242.
陈克均 《中国人民武装警察部队学院学报》2009,25(10):45-47
近年来,随着汽车大批量进入个人家庭,停车难、行路难成为困扰城市交通的大难题,由于城市土地资源越来越匮乏和昂贵,立体停车将是停车产业发展的方向。介绍了机械式立体汽车库的基本形式,分析了其火灾危险性及火灾特点,并探讨了机械式立体汽车库设计的相关要求。 相似文献
243.
This article considers the empty vehicle redistribution problem in a hub‐and‐spoke transportation system, with random demands and stochastic transportation times. An event‐driven model is formulated, which yields the implicit optimal control policy. Based on the analytical results for two‐depot systems, a dynamic decomposition procedure is presented which produces a near‐optimal policy with linear computational complexity in terms of the number of spokes. The resulting policy has the same asymptotic behavior as that of the optimal policy. It is found that the threshold‐type control policy is not usually optimal in such systems. The results are illustrated through small‐scale numerical examples. Through simulation the robustness of the dynamic decomposition policy is tested using a variety of scenarios: more spokes, more vehicles, different combinations of distribution types for the empty vehicle travel times and loaded vehicle arrivals. This shows that the dynamic decomposition policy is significantly better than a heuristics policy in all scenarios and appears to be robust to the assumptions of the distribution types. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008 相似文献
244.
In this study, we propose a new parsimonious policy for the stochastic joint replenishment problem in a single‐location, N‐item setting. The replenishment decisions are based on both group reorder point‐group order quantity and the time since the last decision epoch. We derive the expressions for the key operating characteristics of the inventory system for both unit and compound Poisson demands. In a comprehensive numerical study, we compare the performance of the proposed policy with that of existing ones over a standard test bed. Our numerical results indicate that the proposed policy dominates the existing ones in 100 of 139 instances with comparably significant savings for unit demands. With batch demands, the savings increase as the stochasticity of demand size gets larger. We also observe that it performs well in environments with low demand diversity across items. The inventory system herein also models a two‐echelon setting with a single item, multiple retailers, and cross docking at the upper echelon. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006 相似文献
245.
Johan Marklund 《海军后勤学研究》2002,49(8):798-822
This paper introduces a new replenishment policy for inventory control in a two‐level distribution system consisting of one central warehouse and an arbitrary number of nonidentical retailers. The new policy is designed to control the replenishment process at the central warehouse, using centralized information regarding the inventory positions and demand processes of all installations in the system. The retailers on the other hand are assumed to use continuous review (R, Q) policies. A technique for exact evaluation of the expected inventory holding and backorder costs for the system is presented. Numerical results indicate that there are cases when considerable savings can be made by using the new (α0, Q0) policy instead of a traditional echelon‐ or installation‐stock (R, Q) policy. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 798–822, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10040 相似文献
246.
247.
248.
本文以带宽Toeplitz系统的快速并行解法为基础,通过建立秩1的修正格式讨论了拟带宽Toeplitz系统的一种快速并行算法,其串行运算量为9nh+O(h).设p为处理机台数,当p≤n时,并行运算量为 ;当p=3n时,运算量为2h ̄2log2n+O(1),其中h表示拟带宽宽度。 相似文献
249.
When the US Air Force set out to acquire a new aerial tanker (the KC-X), two highly suitable alternatives were offered. What could have been a short and simple source selection turned into a prolonged embarrassment. The original selection of 100 leased KC-767s was made in May 2003. But the KC-46 is expected to be operational in 2017 – more than a decade later. Our primary purpose here is to narrate and explain key events in the KC-X program. We search for useful paradigms, based in part on the US Government being better viewed as a quarrelsome committee than a monopsonist. In addition, we consider what this case might tell us about the US defense acquisition system. 相似文献
250.
针对武器装备组合规划中存在的选择难、规划难问题,在给定能力需求的条件下,从分析装备的组合变更对整体体系的影响出发,考虑了总的经费预算、年度费用分配、装备规划周期等约束,以能力差距和发展风险最小为准则,构建了双目标优化模型,并设计了基于差分进化和NSGA-II的求解算法,获得模型的Pareto解;最后通过TOPSIS方法从所求Pareto解中求得令决策者满意的折中解。通过一个具体示例,验证了本文所提模型和算法的有效性,能够为武器装备组合规划提供辅助决策。 相似文献