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31.
The dielectric constant (DC) is one of the key properties for detection of threat materials such as Improvised Explosive Devices (IEDs). In the present paper, the density functional theory (DFT) as well as ab-initio approaches are used to explore effective methods to predict dielectric constants of a series of 12 energetic materials (EMs) for which experimental data needed to experimentally determine the dielectric constant (refractive indices) are available. These include military grades energetic materials, nitro and peroxide compounds, and the widely used nitroglycerin. Ab-initio and DFT calculations are conducted. In order to calculate dielectric constant values of materials, potential DFT functional combined with basis sets are considered for testing. Accuracy of the calculations are compared to experimental data listed in the scientific literature, and time required for calculations are both evaluated and discussed. The best functional/basis set combinations among those tested are CAM-B3LYP and AUG-cc-pVDZm, which provide great results, with accuracy deviations below 5% when calculated results are compared to experimental data.  相似文献   
32.
The decision to employ force abroad is often a contentious political decision, where partisanship plays a crucial role. Prior to military intervention, political parties usually make their ideologically distinctive preferences clear and seek to implement them once in power. What remains unclear, however, is how ideology affects the decision to use military force. This article contends that alliance and electoral calculations constrain the ability of political parties to implement their ideological preferences with regards to the use of force. It examines a “most likely” case for the partisan theory of military intervention, namely Canada’s refusal to take part in the invasion of Iraq and its decision to commit forces to the war against the Islamic State. It finds that only in combination with alliance and electoral calculations does executive ideology offer valuable insights into Canada’s military support to U.S.-led coalition operations, which contributes to our understanding of allied decision-making.  相似文献   
33.
In the last decade, cyber conflict has become a main feature of international politics and a growing concern for strategic stability and collective security. Unfortunately, cyber conflict suffers from a lack of conceptual clarity about its impact on collective security and a lack of consensus among international actors on how to interpret it. This article proposes to understand cyber conflict as an evolving process driven by two factors: the way in which digital space is configured and the way in which tactical, organizational, strategic, and doctrinal characteristics related to cyber have been included in the field of national and international security. Both tend to encourage offensive behavior but also demonstrate features pointing to restraint.  相似文献   
34.
Strategic studies deals intimately with the topic of power. Most scholars in the discipline work with a concept of power as an adversarial zero-sum competition. This is natural and necessary. However, other conceptions of power developed within political science and sociology could enrich strategic studies. Approaching two typical, traditional tasks of strategy – alliance building and war-fighting – this article demonstrates the heuristic mileage of theories of collective power. In particular, we can shed new light on the post-Cold War transformation of NATO as well as state-building as a strategy in counter-insurgencies with new ideas of power. Broadening the palette of theories of power is thus valuable if strategic studies is to prosper as an independent field of study.  相似文献   
35.
The aim of this article is to evaluate how French Major Conventional Weapons (MCW) exports impact on the conflict intensity of recipient countries. The recent increase in French arms exports seems to contradict the French political discourse on the promotion of regional stability. We run zero-inflated ordered probit model in order to analyze the role of the arms trade on the intensity of civil conflicts in 144 countries from 1992 to 2014, using SIPRI and UCDP/PRIO data. Our results suggest that French MCW exports tended not to exacerbate intrastate conflicts during this period. This finding is robust to changes in the empirical framework. We propose two lines of explanations: France seems to be prone to choosing partners that respect human rights and selling more ‘defense-oriented’ MCW than the rest of the world.  相似文献   
36.
The structural changes inside the French innovation system have impacted the role of defense firms since the late 1980s. Major changes have affected the defense budget and public R&D funding system in particular. The aim of this article is to understand French defense firms’ repositioning within the National Innovation System (NIS) based on an analysis of their R&D behavior over a long period of time (1987–2010). We show that French defense firms remain major players in the NIS and faced up to these major changes by adapting the funding of their R&D and their research priorities and rolling out new innovation capabilities. Additionally, they developed new innovation models to take advantage of new collaborative partnerships developed for civil and military markets.  相似文献   
37.
The maintenance strategy considered in this article is in the class of block replacement policies. The working unit is replaced by new ones at instants T,2T,3T,… independently of the age and state of the unit. If a failure occurs between these instants, the random repair cost is evaluated. If it is smaller than a predetermined control limit then a minimal repair is carried out. Otherwise the unit is replaced by a used unit. The performance of this maintenance strategy is evaluated in terms of average total cost per time unit over an infinite time span. The mathematical model is defined and several analytical results are obtained. A computer program has been written, which solves the mathematical problem, and some examples are given for the cases where the underlying life distribution is gamma, Weibull or truncated normal.  相似文献   
38.
Why does joint defence production of advanced weapons systems, which appears like a logical choice at first, become harder for both the primary production state and its allies to manage and justify as the acquisition process runs its course? To answer this question, we analyze the multinational politics of the F-35 JSF with a focus on how secondary states who have bought into the program are affected by domestic politics within the primary production state. We find that US congressional and bureaucratic politics, cuts to US defence spending, and a desire to retain tight control over the program has locked allies into a program with which they have little leverage. Potentially losing the ability to fight along side the US if they don’t follow through, coupled with inter-Alliance pressures, leaves secondary states who are involved with the F-35 program, vulnerable to the whims of US domestic politics.  相似文献   
39.
This paper investigates what motivates young people to volunteer for peace-keeping or peace-enforcing missions and how their motives change between pre- and post-deployment. Data include information about social and military background, and motives for more than 600 soldiers, 444 of whom answered the survey both before and after deployment. Soldiers are deployed to different missions under the same circumstances. To conceptualize motives among soldiers, we use factor analysis and find three factors: challenge, self-benefit, and fidelity. Challenge represents an occupational orientation; fidelity, an institutional orientation; and self-benefit, a desire for adventure. Exploiting the within-subject design of our data, we find that pre- and post-deployment motives vary significantly according to the type of mission and soldiers’ previous experiences (first-timers or experienced soldiers). Our results suggest that after the mission, peace-keepers are generally more disappointed than peace-enforcers. Our results also show that self-benefit motives are important for younger soldiers with only a high school education, and that this group usually serves as peace-enforcers during their gap year.  相似文献   
40.
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