全文获取类型
收费全文 | 506篇 |
免费 | 17篇 |
出版年
2021年 | 10篇 |
2020年 | 5篇 |
2019年 | 13篇 |
2018年 | 5篇 |
2017年 | 7篇 |
2016年 | 12篇 |
2015年 | 9篇 |
2014年 | 7篇 |
2013年 | 77篇 |
2011年 | 6篇 |
2009年 | 6篇 |
2007年 | 15篇 |
2005年 | 5篇 |
2004年 | 7篇 |
2003年 | 9篇 |
2002年 | 8篇 |
2001年 | 5篇 |
1999年 | 10篇 |
1998年 | 9篇 |
1997年 | 10篇 |
1996年 | 10篇 |
1995年 | 4篇 |
1994年 | 9篇 |
1993年 | 13篇 |
1992年 | 11篇 |
1991年 | 13篇 |
1990年 | 12篇 |
1989年 | 19篇 |
1988年 | 18篇 |
1987年 | 8篇 |
1986年 | 15篇 |
1985年 | 8篇 |
1984年 | 6篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1980年 | 7篇 |
1979年 | 9篇 |
1978年 | 9篇 |
1977年 | 7篇 |
1976年 | 6篇 |
1975年 | 5篇 |
1974年 | 12篇 |
1973年 | 5篇 |
1972年 | 4篇 |
1971年 | 10篇 |
1970年 | 6篇 |
1969年 | 7篇 |
1968年 | 4篇 |
1967年 | 7篇 |
1948年 | 5篇 |
排序方式: 共有523条查询结果,搜索用时 15 毫秒
441.
A bicriterion approach to common flow allowances due window assignment and scheduling with controllable processing times 下载免费PDF全文
We investigate a single‐machine scheduling problem for which both the job processing times and due windows are decision variables to be determined by the decision maker. The job processing times are controllable as a linear or convex function of the amount of a common continuously divisible resource allocated to the jobs, where the resource allocated to the jobs can be used in discrete or continuous quantities. We use the common flow allowances due window assignment method to assign due windows to the jobs. We consider two performance criteria: (i) the total weighted number of early and tardy jobs plus the weighted due window assignment cost, and (ii) the resource consumption cost. For each resource consumption function, the objective is to minimize the first criterion, while keeping the value of the second criterion no greater than a given limit. We analyze the computational complexity, devise pseudo‐polynomial dynamic programming solution algorithms, and provide fully polynomial‐time approximation schemes and an enhanced volume algorithm to find high‐quality solutions quickly for the considered problems. We conduct extensive numerical studies to assess the performance of the algorithms. The computational results show that the proposed algorithms are very efficient in finding optimal or near‐optimal solutions. © 2017 Wiley Periodicals, Inc. Naval Research Logistics, 64: 41–63, 2017 相似文献
442.
This paper deals with the sequencing problem of minimizing linear delay costs with parallel identical processors. The theoretical properties of this m-machine problem are explored, and the problem of determining an optimum scheduling procedure is examined. Properties of the optimum schedule are given as well as the corresponding reductions in the number of schedules that must be evaluated in the search for an optimum. An experimental comparison of scheduling rules is reported; this indicates that although a class of effective heuristics can be identified, their relative behavior is difficult to characterize. 相似文献
443.
444.
Randall R. Dipert 《Journal of Military Ethics》2013,12(1):34-53
Almost all discussions of cyberwarfare, other cyber-attacks, and cyber-espionage have focused entirely on the Internet as the chief means of damage – the Internet as a ‘vector,’ using a term from the theory of infectious diseases. However there are a variety of means, some of which have already been used, that involve cyber-exploitation using vectors other than the Internet. Malware can be installed in the integrated circuits of computers and servers, but also in any devices attached to them – thumb drives, CDs, printers, scanners, and so on. One can also use various forms of electromagnetic radiation at a distance of meters or more to exfiltrate data or to infiltrate corrupt data. I call this large and diverse family of unwanted interference with the functioning of information processing systems other-than-Internet (OTI) attacks on information systems. Stuxnet, and probably the 2007 Israeli corruption of Syrian air defenses, were OTI attacks. Such OTI techniques are more difficult to develop than creating malware, requiring electronic manufacturing facilities or novel technologies, and are thus accessible only to larger corporations and technologically sophisticated countries. Particularly vulnerable would be countries (like the United States and Europe) whose information processing devices are mainly produced outside of the country. Once exploitations via the Internet become harder to perpetrate, OTI exploitations are certain to grow dramatically, eventually requiring equipment for critical uses to be expensively fabricated in (and transported using) secure facilities; expensive detection measures will have to be instituted. This will create challenges for policy, law, and ethics, as well as greatly increasing the cost of many electronic devices. 相似文献
445.
JOHN T. WARNER & SEBASTIAN NEGRUSA 《Defence and Peace Economics》2013,24(2):83-100
This paper examines the trade and military relationship between two countries which have a common military enemy. The paper explains how the former two countries, which are military allies and trading partners, share the burden of defence against the third country. It demonstrates how the defence production of a country may hurt its ally because the latter country's terms of trade can be deteriorated. Whether or not a smaller ally spends less on defence is analyzed. Also analyzed is the effects of the reactions of the enemy country on the trade between the two allies and their welfare. 相似文献
446.
When rational choice theory is applied to the study of terrorism, it is important that attention be given to the derived principles of constrained utility maximization. Particularly useful is the Slutsky equation, which rigorously analyzes the quantity response in one activity to a price change in another. By directing attention to assumptions and/or information about compensated cross price elasticities, expenditure shares, and income elasticities, the Slutsky equation can provide critical guidance in both theoretical and empirical analysis. 相似文献
447.
MARTIN R RUPIYA 《African Security Review》2013,22(1):83-89
Abstract This paper seeks to critically appraise Africa's position within the United Nations Security Council from the inception of the UN in 1945 until the end of 2010, spanning the entire history of the world body. A few factors make such an appraisal a useful exercise. These include the ongoing debates about the reform of the Council in particular and the UN as a whole, and the growing interest that many African students and observers of and actors in international relations seem to have developed in recent years in the working of the world body. In this appraisal, emphasis will be placed on the origin and rationale behind the establishment of the Security Council as well as the use of the veto power by its permanent members, with a special reference to Africa. 相似文献
448.
We identify the causal effect of a reduction in military personnel on a number of socioeconomic indicators within the peripheries of military bases. The base realignments and closures in Germany are used as an exogenous source of variation that allows us to identify the effect of a demand shock on household income, output, unemployment, and tax revenue within a specified buffer zone around each base. The analysis covers 298 communities for the period 2003–2007. Consistent with evidence found elsewhere, we find that these base adjustments have only a marginal impact on the local community in which the bases are located. 相似文献
449.
450.
Jon R Lindsay 《战略研究杂志》2013,36(3):422-453
Two big ideas have shaped recent debate about military doctrine: the Revolution in Military Affairs (RMA) and Counterinsurgency (COIN). These ‘network centric’ and ‘population centric’ worldviews appear contradictory, but this is a false dichotomy. American forces have actively developed RMA concepts in COIN environments during recent wars in Iraq and Afghanistan; the exemplar par excellence is innovation by US Special Operations Command (SOCOM) in doctrine, technology, and organization for counterterrorism. Ironically, SOCOM's reimagining of the RMA managed to both improve the strengths and underscore the weaknesses of the American military's technological prowess. 相似文献