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791.
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Despite the large number and variety of studies addressing the relationship between military spending and economic growth, a consensus regarding the exact nature of any relationship between the two has proven elusive. This study uses a panel co-integration approach to examine the relationship between military spending and economic growth in the five South Asian countries of India, Pakistan, Nepal, Sri Lanka and Bangladesh over the period of 1988–2007. It finds that a 1% increase in military spending increases real GDP by only 0.04%, suggesting that the substantial amount of public expenditure that is currently directed towards military purposes in these countries has a negligible impact upon economic growth. 相似文献
793.
We schedule a set of illuminators (homing devices) to strike a set of targets using surface-to-air missiles in a naval battle. The task is viewed as a production floor shop scheduling problem of minimizing the total weighted flow time, subject to time-window job availability and machine downtime side constraints. A simple algorithm based on solving assignment problems is developed for the case when all the job processing times are equal and the data are all integer. For the general case of scheduling jobs with unequal processing times, we develop two alternate formulations and analyze their relative strengths by comparing their respective linear programming relaxations. We select the better formulation in this comparison and exploit its special structures to develop several effective heuristic algorithms that provide good-quality solutions in real time; this is an essential element for use by the Navy. © 1995 John Wiley & Sons, Inc. 相似文献
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796.
The idea of deploying noncollocated sources and receivers in multistatic sonar networks (MSNs) has emerged as a promising area of opportunity in sonar systems. This article is one of the first to address point coverage problems in MSNs, where a number of points of interest have to be monitored in order to protect them from hostile underwater assets. We consider discrete “definite range” sensors as well as various diffuse sensor models. We make several new contributions. By showing that the convex hull spanned by the targets is guaranteed to contain optimal sensor positions, we are able to limit the solution space. Under a definite range sensor model, we are able to exclude even more suboptimal solutions. We then formulate a nonlinear program and an integer nonlinear program to express the sensor placement problem. To address the nonconvex single‐source placement problem, we develop the Divide Best Sector (DiBS) algorithm, which quickly provides an optimal source position assuming fixed receivers. Starting with a basic implementation of DiBS, we show how incorporating advanced sector splitting methods and termination conditions further improve the algorithm. We also discuss two ways to use DiBS to find multiple source positions by placing sensors iteratively or simultaneously. © 2017 Wiley Periodicals, Inc. Naval Research Logistics 64: 287–304, 2017 相似文献
797.
Ronald D. Fricker 《海军后勤学研究》1998,45(1):1-22
This paper revisits the modeling by Bracken [3] of the Ardennes campaign of World War II using the Lanchester equations. It revises and extends that analysis in a number of ways: (1) It more accurately fits the model parameters using linear regression; (2) it considers the data from the entire campaign; and (3) it adds in air sortie data. In contrast to previous results, it concludes by showing that neither the Lanchester linear or Lanchester square laws fit the data. A new form of the Lanchester equations emerges with a physical interpretation. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 1–22, 1998 相似文献
798.
Richard B. Streeter Guy W. Hagen Edward E. Patenaude Dennis K. Killinger 《Defence and Peace Economics》2013,24(6):569-587
This paper presents a model for converting legacy defense production facilities into private‐sector economic resources. Specifically, this paper will examine as a case study the first successful conversion of a former U.S. Department of Energy nuclear weapons production installation, including reasons for its success, its costs and benefits, and lessons for public policy. It is envisioned that this model may be useful for mitigating local economic hardship resulting from defense “downsizing” and for privatizing production capacities critical for national defense. 相似文献
799.
Shireen K. Burki 《Defense & Security Analysis》2013,29(3):234-252
There is widespread acknowledgment that the modus operandi of jihadis affiliated with Al Qaeda and associated movements (AQAM) relies on brutal terror-inducing tactics which, more often than not, target Muslim and non-Muslim non-combatants. This article comparatively analyzes the AQAM modus operandi within the traditional stipulations of Islamic precepts with respect to waging jihad al saghir. The purpose is to glean whether or not such tactics such as suicide bombings, declaring fellow Muslim apostates in order to kill them, use of IEDs and EFPs to target civilians, constitute legitimate rules of engagement in jihad al saghir. 相似文献
800.
This article proposes a mathematical-programming-based approach to solve the classification problem in discriminant analysis which explicitly considers the classification gap. The procedure consists of two distinct phases and initially treats the classification gap as a fuzzy set in which the classification rule is not yet established. The nature of the classification gap is examined and a variety of methods are discussed which can be applied to identify the most appropriate classification rule over the fuzzy set. The proposed methodology has several potential advantages. First, it offers a more refined approach to the classification problem, facilitating careful analysis of the fuzzy region where the classification decision may not be obvious. Secondly, the two-phase approach enables the analysis of larger data sets when using computer-intensive procedures such as mixed-integer programming. Finally, because of the restricted choice of separating hyperplanes in phase 2, the approach appears to be more robust than other classification techniques with respect to outlier-contaminated data conditions. The robustness issue and computational advantage of our proposed methodology are illustrated using a limited simulation experiment. 相似文献