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1.
This paper empirically analyses the effect of terror on internal migration between Israeli subdistricts. Using a unique data-set comprising migration flows for the period 1999–2012 and the number of rocket and non-rocket attacks, we test the hypotheses that terror reduces migration into an affected subdistrict and increases migration out of it. According to our results, the effect of terror on migration is asymmetric as we only find evidence for the first hypothesis. This result remains when we use an instrumental variables strategy that corrects for underreporting of the number of rocket attacks. The largest effects of rocket attacks are found for migration into the Southern subdistrict of Ashqelon as well as into other border regions in Northern Israel, while non-rocket attacks also have substantial effects in the more populous centres of Jerusalem and Tel Aviv.  相似文献   

2.
Nuclear proliferation, lax security standards in the storage of fissile materials, and international apathy in the prosecution of terrorists make nuclear terror a serious threat to the United States and its allies, yet no doctrine of retaliation has been established. To decrease the probability of terrorist use of nuclear weapons, a doctrine of retaliation—a negligence doctrine—should be considered. If the United States can distinguish whose fissile material was used for a nuclear terror event, a negligence doctrine would prescribe retaliation against that state. Where the proximate cause—terrorists—is unavailable for deterrent retaliation, deterring an accessible mediate cause—a state that has failed to adequately secure its fissile material—is one of a few effective alternatives. In the absence of such a negligence doctrine, the United States and its allies are increasingly vulnerable to a nuclear terror attack and the ensuing negative consequences.  相似文献   

3.
模糊离散动态贝叶斯网络的目标威胁等级评估   总被引:1,自引:0,他引:1  
动态贝叶斯网络作为一种智能推理工具在处理不确定推理问题中显示出强大的生命力,但是存在难于处理连续变量的推理问题。将模糊理论与动态贝叶斯网络相结合,提出一种模糊分类的方法,将连续变量模糊分类为动态贝叶斯网络能够应用的证据信息用于推理,并建立目标威胁等级评估模型,应用直接推理算法对该网络进行推理。仿真结果表明,该分类方法与动态贝叶斯网络结合能够很好地处理连续变量推理的问题。  相似文献   

4.
Cyberspace is a new domain of operation, with its own characteristics. Cyber weapons differ qualitatively from kinetic ones: They generate effects by non-kinetic means through information, technology, and networks. Their properties, opportunities, and constraints are comparable to the qualitative difference between conventional and nuclear weapons. New weapons and their target sets in a new domain raise a series of unresolved policy challenges at the domestic, bilateral, and international levels about deterrence, attribution, and response. They also introduce new risks: uncertainty about unintended consequences, expectations of efficacy, and uncertainty about both the target’s and the international community’s response. Cyber operations offer considerable benefits for states to achieve strategic objectives both covertly and overtly. However, without a strategic framework to contain and possibly deter their use, make state and non-state behavior more predictable in the absence of reciprocal norms, and limit their impact, an environment where states face persistent attacks that nonetheless fall below the threshold of armed conflict presents a policy dilemma that reinforces collective insecurity.  相似文献   

5.
Abstract

In this research, we analyzed how Turkish financial markets and foreign investors in the stock market reacted to the terror attacks in Turkey. Our analysis, which was performed using the terror index for the stock market and the foreign exchange market, revealed that returns, abnormal returns, and cumulative abnormal returns were not affected by the terror attacks; however, foreign investors in the stock market were affected. When the geographic regions of the terror attacks were analyzed, the findings showed that foreign investors were negatively affected mainly by the terror attacks that occurred in southeast Anatolia. Attack type and target type were important only for foreign investors. An evaluation of the interaction between the terror attacks and the markets with the involvement of the terrorist organizations indicated that only the foreign investors in the stock market were affected by Al-Qaeda and PKK-linked terror attacks. An evaluation of the effect of terror attacks in foreign countries on Turkish financial markets revealed no effect on the domestic stock market and foreign exchange markets. We also examined the volatility spillovers from the terror index to the stock market and found that terrorist attacks increased the volatility of the stock market.  相似文献   

6.
Targeted killings have become a central tactic in the United States' campaigns against militant and terrorist groups in the Middle East, Asia, and Africa. Both ‘demand’ and ‘supply’ factors explain the rise of targeted killings. Demand for targeted killings increased as the United States faced new threats from militant groups that could not be effectively countered with conventional military force. Concerns about the political consequences of long-term military involvement overseas and American casualties led political leaders to supply more targeted killings. The conclusion discusses how this tactic may have unintended consequences as other states follow the United States use of targeted killings.  相似文献   

7.
Classification among groups is a crucial problem in managerial decision making. Classification techniques are used in: identifying stressed firms, classifying among consumer types, and rating of firms' bonds, etc. Neural networks are recognized as important and emerging methodologies in the area of classification. In this paper, we study the effect of training sample size and the neural network topology on the classification capability of neural networks. We also compare neural network capabilities with those of commonly used statistical methodologies. Experiments were designed and carried out on two-group classification problems to find answers to these questions. The prediction capability of the neural network models are better than traditional statistical models. The learning capability of the neural networks is improving compared to traditional models because the discriminate function is more complex. For real world classification problems, the usage of neural networks is highly recommended, for two reasons: learning capability and flexibility. Learning capability: Neural network classifies better in sterile experiments as performed in this research. Flexibility: Real life data are rarely not contaminated with noise, such as unknown distributions, and missing variables, etc. Neural networks differ from a statistical model that it is not dependent on any assumption concerning the data set distribution. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 699–717, 1997  相似文献   

8.
This work continues to develop the 'netwar' concept that the authors introduced in 1993 and have expanded upon in their various RAND and other writings ever since. Deeper understanding of the nature, strengths and vulnerabilities of networks will prove useful in combating terrorism and transnational crime, but also in understanding militant social activism, both of the violently disruptive sort and that which aims at fostering the rise of a global civil society. This essay also assesses recent US performance in the terror war, and concludes by raising concerns over the possible rise of a new form of network-based fascism.  相似文献   

9.
Foreign Legions in the generic sense have evolved in ways that would surprise Beau Geste. Not only are more foreigners or recent immigrants enlisting in Western military forces, but also the post-Cold War era has seen the revival of warlord militias and Private Military Companies. Western militaries, in particular that of the United States, have also sought to increase their strategic reach through security assistance to regional military forces. While there have been some successes, security assistance has proven to have its limitations, not to mention unintended consequences for civil military relations, democracy promotion, and military efficiency.  相似文献   

10.
联合作战条件下,指挥决策人员在海量描述战场态势的数据和信息面前往往会束手无策,无法快速作出正确的决策。贝叶斯网络模型是一种基于概率推理的网络化数学模型,能够通过一些变量的信息来获取其他的概率信息,从而解决不定性和不完整性问题。提出了一种基于贝叶斯网络的空中目标威胁估计算法,用空中威胁网络模型找到空中威胁目标各属性之间的潜在关系,并建立空中目标威胁估计算法,最后以一个实例来验证该空中目标威胁估计的计算过程和有效性。  相似文献   

11.
The economic theory of defense has traditionally described public safety as achieved through investments that deter adversaries. Deterrence is, however, ineffective and pre‐emptive defense is required when a population of intended victims confronts supreme‐value suicide terror. A moral dilemma then arises, since pre‐emption may impose collective punishment, while in the absence of pre‐emption the population of intended victims is exposed to acts of terror. We consider how a population of intended terror victims confronts the moral dilemma, and compare the threatened population's response with the public‐safety recommendations of external judges who are not personally affected by the threat of terror.  相似文献   

12.
Abstract

In spite of government counter-terrorism expenditure and efforts, the incidence of terrorism in Nigeria appears to be rising. This paper examines the growth and fiscal consequences of terrorism in Nigeria by estimating the terrorism–macroeconomy relation using different measures of terror incidence. The results show that terrorism has an economically and statistically significant negative impact on growth; although this impact is considerably small and short-lived, manifesting only after a lag of about three years. Specifically, the cost of terrorism to Nigeria, in terms of lost GDP per annum, is estimated at 0.82%. Moreover, there is evidence that terrorism leads to the reallocation of economic activity away from private investment spending to government spending; that is, terrorism crowds out investment at a higher rate than its potential to crowd in government spending. Lastly, terrorism alters the composition of government expenditure – with the defence component of government expenditure rising vis-a-vis other expenditure items. The results are robust to allowing for dynamic interactions between terrorism and macroeconomic aggregates.  相似文献   

13.
随着新疆高饺的校园网建设逐渐由硬件基础建设阶段转入软件和资源建设阶段,本文就新疆高校校园网建设的现状及出现的一些问题做了探讨和分析,并对如何加强高校校园网建设,充实网络教学资源,强化校园网知识培训,提高师生应用能力等一系列问题提出了建议,以期为新疆高校的信息化建设提供一些借鉴。  相似文献   

14.
This article presents a dynamic model in which counterterrorism policies have the potential to generate positive public support for terrorism via a backlash that may fuel terror recruitment. For an optimizing government aiming at maximizing security, this phenomenon produces a natural bound on proactive counterterror policy that is related to the dynamic path of conflict. Moreover, terror is a persistent phenomenon that requires patience on the part of the target government for optimal counterterror policies to be realized. Finally, the potential for backlash yields insights into the need for target governments to fight an information war to change public opinion regarding its own policies and the ultimate effect of terror attacks.  相似文献   

15.
In this paper we consider networks that consist of components operating under a randomly changing common environment. Our work is motivated by power system networks that are subject to fluctuating weather conditions over time that affect the performance of the network. We develop a general setup for any network that is subject to such environment and present results for network reliability assessment under two repair scenarios. We also present Bayesian analysis of network failure data and illustrate how reliability predictions can be obtained for the network. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 574–591, 2003  相似文献   

16.
Counterterrorism operations in Kenya have often been hindered by a lack of collaboration, coordination and cooperation among the security agencies involved in such operations. This article examines the relationship between neo-elitism and counterterrorism security interagency activity in Kenya. Using neo-elitism as a framework for analysis, with specific reference to the September 2013 Westgate Mall attack counterterrorism operation, it is argued that the lack of collaboration, coordination and cooperation among Kenya’s counterterrorism security agencies often results in unintended adverse consequences. The interagency conflict over the Westgate operation was primarily about command and control, intelligence sharing and official information shared with the public pertaining to the stages of the siege and operation. These security agencies share similar responsibilities and jurisdictions in the rest of the country’s counterterrorism efforts. The interagency conflicts reveal that the country’s security elites pursue personal and agency-specific interests that are aimed at maintaining organisational supremacy over counterterrorism efforts. Recommendations are offered for how to tackle the problem of interagency conflict in order to enhance the effectiveness of counterterrorism operations in Kenya.  相似文献   

17.
Abstract

The siege of the northern Syrian town of Kobane was lifted in January 2015. The Kurdish defenders there had triumphed against Islamic State (IS). The conflict then moved on. It moved on, though, with the United States, the United Kingdom, and other Western powers having adopted, almost by default, the Kurds as proxy fighters in this conflict. The Kurds, however, are a divided and fractious nation spread across three states and historically famous for fighting among themselves. In employing the Kurds as proxies against IS, as this article shows, these Western powers must be aware of the unintended consequences that can result.  相似文献   

18.
We introduce a multi‐period tree network maintenance scheduling model and investigate the effect of maintenance capacity restrictions on traffic/information flow interruptions. Network maintenance refers to activities that are performed to keep a network operational. For linear networks with uniform flow between every pair of nodes, we devise a polynomial‐time combinatorial algorithm that minimizes flow disruption. The spiral structure of the optimal maintenance schedule sheds insights into general network maintenance scheduling. The maintenance problem on linear networks with a general flow structure is strongly NP‐hard. We formulate this problem as a linear integer program, derive strong valid inequalities, and conduct a polyhedral study of the formulation. Polyhedral analysis shows that the relaxation of our linear network formulation is tight when capacities and flows are uniform. The linear network formulation is then extended to an integer program for solving the tree network maintenance scheduling problem. Preliminary computations indicate that the strengthened formulations can solve reasonably sized problems on tree networks and that the intuitions gained from the uniform flow case continue to hold in general settings. Finally, we extend the approach to directed networks and to maintenance of network nodes. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   

19.
ABSTRACT

Debates on military intervention and small wars often include the claim that soldiers should operate among civilians in order to avoid civilian casualties and to protect civilians against third-party violence. This article, by contrast, points at negative unintended consequences of military operations taking place in close proximity to local populations: it argues that also risk-tolerant militaries cause civilian casualties and that their presence triggers third-party violence against civilians. The British military, in particular the British Army, exported risk-tolerant practices from Northern Ireland to the Balkans, with sporadic success. But in southern Iraq and in Helmand, British ground operations harmed civilians. The findings suggest that the chances for protection are better in operations where levels of violence are relatively low than in counterinsurgency where troops face ruthless and well-endowed enemies operating among civilians.  相似文献   

20.
相依网络研究综述   总被引:2,自引:1,他引:1       下载免费PDF全文
网络相依性和相依网络研究已经成为近年来复杂网络领域的热点,但是目前对相关研究进展进行综合归纳的文献却不多见。在对国内外相关文献进行系统分析的基础上,简要介绍相依网络研究涉及的渗流理论;描述该类型网络的级联失效过程;从相依网络的子网络特性、相依边的方向和类型、子网络组合方式等三个角度对相依网络鲁棒性的研究成果进行总结;并从理论和应用两方面对未来相依网络研究的发展方向进行展望。  相似文献   

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