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51.
This article introduces integro-differential equations as a new technique to study terrorism dynamics. An integro-differential equation is a mathematical expression that contains derivatives of the required function and its integral transforms. The technique is applied to two different dynamic models in terrorism: terrorism and tourism, and terrorist innovations. In the first model the number of tourists that appears in an integral term and also in a derivative term is impacted by the number of terrorists. In the second model the integro-differential equation for terrorist innovations relates them to terrorist attacks. The article shows how to solve, analyze, interpret, and deal with integro-differential equations. Integro-differential equations shed light on aspects of the models ignored when other techniques are used. This is particularly important for the evaluation of current counterterrorist policies, as well as to the formulation of new ones.  相似文献   
52.
ABSTRACT

This 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   
53.
ABSTRACT

The recent use of chemicals in warfare in Syria and Iraq illustrates that, despite the important work of the 1997 Chemical Weapons Convention (CWC), the world has not yet been totally successful in stopping the use of indiscriminate toxic agents in conflicts, either by states or non-state actors. Michael Crowley's excellent and timely new book, Chemical Control, analyzes the use of “riot control agents” (RCAs) and “incapacitating chemical agents” (ICAs), including launch and dispersal systems, by police, paramilitary, and military forces over the last decades and raises the challenging question about where the red line might be drawn between banned and permitted uses of chemicals. He discusses this problem not only in the context of the CWC, which allows use of RCAs for civilian riot control, but also in the context of international law, human rights, and criminal justice, including the Biological and Toxin Weapons Convention and other disarmament and abolition regimes. He proposes a “holistic, three-stage approach” to addressing this issue “for effective regulation or prohibition of the weapon or weapon-related technology of concern.” As we approach the global abolition of a whole class of weapons of mass destruction in the next decade or even sooner, Chemical Control is helpful in better understanding and solving the dilemma of what's actually banned or permitted under international law, and precluding states undermining the chemical weapons ban.  相似文献   
54.
ABSTRACT

In March 2015, the South Australian state government established a royal commission to investigate the financial, social, technical, diplomatic, and nonproliferation benefits and risks of expanding its nuclear industry, including activities related to uranium mining; enriching, reprocessing, and fabricating nuclear fuels for both domestic use and export; producing nuclear power; and storing radiological waste, including foreign spent reactor fuel. Given its enormous uranium reserves and current mining activities, some Australians have argued that Australia could benefit financially by expanding the mining sector and by adding value to its uranium exports by enriching the material and fabricating it into reactor fuel assemblies. Others have maintained that Australia can realize significant economic benefits by recycling and storing foreign spent fuel and producing carbon-free nuclear power. In the end, the commission recommended that Australia consider opening up a high-level waste repository to take in foreign spent fuel. It did not recommend any other nuclear activities at this time. The following viewpoint is based on testimony I delivered to the commission on the nuclear weapon proliferation implications of the proposed activities. If Australia wants to avoid the temptation of selling nuclear goods to states that might use these goods to make bombs, it should only consider new nuclear activities that can be entirely financed by the private sector and turn a profit without having to resort to foreign sales. This policy would also enable Australia to set an important, new international nonproliferation standard.  相似文献   
55.
ABSTRACT

What restrains states from employing chemical weapons during modern war? Despite widespread and consistent efforts by the international community to outlaw chemical weapons in the twentieth century, major deviations from this goal occur. Two of the strongest explanations that exist for this trend are the logics of deterrence and norms that consider the use of chemical weapons to be a taboo. We test these theories using factor analysis and find that norms provide a better explanation of non-use in the twentieth century among states with a chemical-weapon capability. We then conclude with avenues for future research in this burgeoning field of study, which includes closer qualitative examination of norms, as well as the expansion of the dataset to include intrastate warfare and non-state warfare.  相似文献   
56.
一种新型CVD铁涂层吸波纤维   总被引:2,自引:0,他引:2       下载免费PDF全文
利用Fe(CO)5受热分解,以CVD方法在SiC纤维表面涂覆单质铁的涂层。研究表明,涂层的引入对SiC纤维力学性能基本没有损伤;纤维依靠涂层导电,其电阻率显著降低;改变工艺条件,可以在较大范围内调节涂层纤维的介电常数,同时也引入了磁损耗机制;采用较低的沉积温度和较高的载气流速,可以提高介电常数和磁导率,同时有好的频散效应。  相似文献   
57.
石河子市作为新疆第三大城市,其体育产业的发展明显滞后。本文通过对石河子市体育产业现状的调查分析,阐述了该市体育产业发展的不足之处,旨在为石河子市体育产业向健康、可持续的方向发展提供参考。  相似文献   
58.
消防安全隐患是化工实验室存在的诸多安全隐患中最大的隐患,其危害性也最为严重。对化工类实验室的消防安全隐患进行分析,研究探讨化工类实验室防火安全管理措施,提高该类场所预防火灾的能力。  相似文献   
59.
案例教学首先要了解“案例教学法”的含义及特点,在此基础上介绍《化学事故应急救援》的课程特点,并就该课程案例教学实施过程中案例的选取、课堂案例讨论、案例总结与评价等问题进行分析,最后对案例教学实施中应注意的问题提出三点意见。  相似文献   
60.
针对全国各地石化工业园区不断新建,化学灾害事故风险增大,以及灾害事故处置难度大的问题,以天津滨海新区石化工业园区为例,对石化工业园区灾害事故风险进行了全面分析,有针对性地提出了石化工业园区灾害事故处置的对策与建议。  相似文献   
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