首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   796篇
  免费   304篇
  国内免费   75篇
  2024年   1篇
  2023年   9篇
  2022年   8篇
  2021年   23篇
  2020年   25篇
  2019年   19篇
  2018年   15篇
  2017年   36篇
  2016年   54篇
  2015年   31篇
  2014年   57篇
  2013年   66篇
  2012年   64篇
  2011年   67篇
  2010年   34篇
  2009年   72篇
  2008年   49篇
  2007年   53篇
  2006年   74篇
  2005年   62篇
  2004年   56篇
  2003年   46篇
  2002年   37篇
  2001年   35篇
  2000年   33篇
  1999年   22篇
  1998年   27篇
  1997年   13篇
  1996年   17篇
  1995年   11篇
  1994年   16篇
  1993年   5篇
  1992年   18篇
  1991年   6篇
  1990年   9篇
  1989年   3篇
  1988年   2篇
排序方式: 共有1175条查询结果,搜索用时 218 毫秒
141.
本文详细介绍了用VB实现分布式监控系统中的数据通讯,用数据通信将微机连在一起实现数据共享,从而对发射机状态进行集中监视管理和分散控制。  相似文献   
142.
基于随机Petri网的综合航电系统建模及分析   总被引:2,自引:0,他引:2  
提出了一种利用随机Petri网对综合航电系统进行建模和性能分析的方法.首先,建立了综合航电系统数据总线传输系统的随机Petri网系统模型,通过系统模型进行综合航电系统的性能分析;其次,给出了航空电子综合系统数据总线传输基于固定主控端周期指令的总线性能分析结果;最后,通过两种分析结果的比较,得出了基于随机Petri网对航空电子综合系统数据总线传输建模分析是可行的结论.  相似文献   
143.
We study sequencing situations with a fixed initial order and linear cost functions. Cost savings can be obtained by rearranging jobs. Next to finding an optimal order, an additional issue is formed by the division of these savings. Cooperative game theory studies this issue. A common assumption states that cooperation between players is restricted to groups that are connected according to the initial order. The value of disconnected groups is defined additively over their connected components. In this paper we allow players in disconnected coalitions to switch places as long as they do not hurt the players not in the coalition under consideration. The resulting games are called relaxed sequencing games. Although they have been studied before, no general results on stable profit divisions have been derived so far. In this paper we prove that relaxed sequencing games have a nonempty core, i.e., they all have stable profit divisions. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
144.
We consider the problem of scheduling orders on identical machines in parallel. Each order consists of one or more individual jobs. A job that belongs to an order can be processed by any one of the machines. Multiple machines can process the jobs of an order concurrently. No setup is required if a machine switches over from one job to another. Each order is released at time zero and has a positive weight. Preemptions are not allowed. The completion time of an order is the time at which all jobs of that order have been completed. The objective is to minimize the total weighted completion time of the orders. The problem is NP‐hard for any fixed number (≥2) of machines. Because of this, we focus our attention on two classes of heuristics, which we refer to as sequential two‐phase heuristics and dynamic two‐phase heuristics. We perform a worst case analysis as well as an empirical analysis of nine heuristics. Our analyses enable us to rank these heuristics according to their effectiveness, taking solution quality as well as running time into account. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
145.
Consider a project during the life cycle of which there are cash payouts and in‐flows. To better meet his financial commitments, the project owner would like to meet all deadlines without running out of cash. We show that the cash availability objective is similar to the total weighted flowtime used to measure work‐in‐progress performance in the scheduling and inventory control literatures. In this article we provide several specialized solution methods for the problem of minimizing total weighted flowtime in an arbitrary acyclic project network, subject to activity release times and due dates, where the activity weights may be positive or negative and represent cash in‐ and out‐flows. We describe the structure of an optimal solution and provide several efficient algorithms and their complexity based on mincost and maxflow formulations. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
146.
基于蚁群算法的试验流程优化研究   总被引:4,自引:2,他引:2  
水中兵器的海上试验涉及许多人员、兵力、被试产品、测量设备等,试验周期长、消耗大,因此如何缩短试验周期是亟待研究解决的问题.文中首先将试验流程优化问题转化为车间调度问题,建立了相应的数学模型,再应用蚁群算法转移规则得到中间结果并进行排队以对各种资源约束进行处理.最后将结果利用局部搜索算法优化后作为蚁群算法信息素更新的基础.实例计算结果表明,该方法优化效果良好.  相似文献   
147.
This paper examines the impact of military spending on general government debt in the enlarged European Union (EU) countries. For this purpose, we use panel data analysis and provide estimates from a dynamic Generalized Method of Moments (GMM) panel model. The dynamics are found to be important and the results suggest that military expenditures do have a large positive impact on the share of general government debt in the EU.  相似文献   
148.
位置随动系统动态性能自动检测研究   总被引:1,自引:0,他引:1  
通过分析某型位置随动系统的组成和动态技术指标,提出了位置随动系统动态性能自动检测的设计方案和测试方法,利用信号仿真模块和基于DSP的高速数据采集与处理模块,建立了自动检测的硬件电路和软件结构,确定了测试位置随动系统的动态性能指标、测试方法和软件功能,实现了对某型位置随动系统动态性能的自动检测.  相似文献   
149.
针对部队实兵对抗实验数据生成和采集的投入高、难度大的实际,提出基于小样本数据生成作战计划的方法:首先,采用偏最小二乘回归分析法建立作战因素与作战结果间的多元非线性模型;其次,采用改进的遗传算法,在MATLAB平台编程实现了对模型的整数规划求解,并通过实例验证算法的有效性;最后,利用作战因素的重要性排序分析作战计划的调整流程。  相似文献   
150.
针对计算机辅助指挥调度舰载机甲板作业的决策过程无法脱离人参与这一特点,引入基于逆向学习的强化学习方法,将指挥员或专家的演示作为学习对象,通过分析舰载机的甲板活动,建立舰载机甲板调度的马尔可夫决策模型(MDP)框架;经线性近似,采用逆向学习方法计算得到回报函数,从而能够通过强化学习方法得到智能优化策略,生成舰载机甲板调度方案。经仿真实验验证,本文所提方法能够较好地学习专家演示,结果符合调度方案优化需求,为形成辅助决策提供了基础。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号