全文获取类型
收费全文 | 475篇 |
免费 | 5篇 |
国内免费 | 3篇 |
出版年
2021年 | 5篇 |
2020年 | 8篇 |
2019年 | 4篇 |
2017年 | 11篇 |
2016年 | 10篇 |
2015年 | 8篇 |
2014年 | 8篇 |
2013年 | 56篇 |
2012年 | 23篇 |
2011年 | 31篇 |
2010年 | 24篇 |
2009年 | 18篇 |
2008年 | 28篇 |
2007年 | 15篇 |
2006年 | 17篇 |
2005年 | 6篇 |
2004年 | 4篇 |
2002年 | 4篇 |
2001年 | 4篇 |
1999年 | 2篇 |
1998年 | 6篇 |
1997年 | 6篇 |
1995年 | 5篇 |
1994年 | 4篇 |
1993年 | 10篇 |
1992年 | 7篇 |
1991年 | 6篇 |
1990年 | 2篇 |
1989年 | 12篇 |
1988年 | 3篇 |
1987年 | 10篇 |
1986年 | 10篇 |
1985年 | 7篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1981年 | 8篇 |
1980年 | 9篇 |
1979年 | 11篇 |
1978年 | 4篇 |
1977年 | 6篇 |
1976年 | 7篇 |
1975年 | 7篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1972年 | 12篇 |
1971年 | 3篇 |
1970年 | 3篇 |
1969年 | 9篇 |
1968年 | 7篇 |
1966年 | 3篇 |
排序方式: 共有483条查询结果,搜索用时 265 毫秒
131.
132.
ABSTRACTThis study seeks to evaluate the threat of malicious chemical use by non-state actors. It finds that non-state actors have primarily turned to ready-to-use crude chemical weapons (CW) instead of traditional CW agents. Interestingly, the worst crude CW attacks have been more destructive than those employing traditional CW. Scenarios for catastrophic consequences exist, but chemical attacks have typically been used to accomplish tactical goals, which leverage psychological and economic impacts. Therefore, successful efforts to counter CW proliferation by non-state actors must be substantially different from those targeting states. 相似文献
133.
134.
135.
设计了四轮全向移动机器人的传感器信息采集硬件电路,并通过分析四轮全向移动机器人的运动学模型,提出了基于TI公司最新研发的TMS320F28069为主控制器的直流电机双闭环速度控制方案.试验结果表明:所提控制方案能够满足四轮全向移动机器人速度控制的要求,且响应速度快、误差小. 相似文献
136.
Ordered flow shop models have appeared in the literature since the mid‐1970s and proportionate flow shop models have appeared since the early 1980s. We provide a detailed review of these models along with some analysis and potential topics for future research. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
137.
This paper examines whether non-lethal weapons (NLWs) enhance the capability of the US armed forces to conduct irregular warfare (IW) operations. With expectations that the operational environment will only continue to become more complex in the future, NLWs may reduce the level of violence received, as well as dispensed, by US forces while performing tasks in the IW spectrum. We argue that NLWs increase the ability of US forces to address the long tail of warfare and their deployment should be increased in the near term. 相似文献
138.
139.
140.
In this article we introduce a 2‐machine flowshop with processing flexibility. Two processing modes are available for each task: namely, processing by the designated processor, and processing simultaneously by both processors. The objective studied is makespan minimization. This production environment is encountered in repetitive manufacturing shops equipped with processors that have the flexibility to execute orders either individually or in coordination. In the latter case, the product designer exploits processing synergies between two processors so as to execute a particular task much faster than a dedicated processor. This type of flowshop environment is also encountered in labor‐intensive assembly lines where products moving downstream can be processed either in the designated assembly stations or by pulling together the work teams of adjacent stations. This scheduling problem requires determining the mode of operation of each task, and the subsequent scheduling that preserves the flowshop constraints. We show that the problem is ordinary NP‐complete and obtain an optimal solution using a dynamic programming algorithm with considerable computational requirements for medium and large problems. Then, we present a number of dynamic programming relaxations and analyze their worst‐case error performance. Finally, we present a polynomial time heuristic with worst‐case error performance comparable to that of the dynamic programming relaxations. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004. 相似文献