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101.
In the history of warfare, there are a number of examples of strategic uses of asymmetric technologies. Consistent with history and theory, individuals, organizations and nations have spotted opportunities to employ information and communications technologies to gain and exploit asymmetric advantages and to counter asymmetric weaknesses. This article discusses various asymmetries associated with institutions, nations and organizations that influence the ICT-national security nexus. Regulative, normative and cognitive institutions in a country provide various mechanisms that affect the nature of positive and negative asymmetries. Nations and organizations also differ in terms of their capability to assimilate ICT tools to gain positive asymmetries and deal with vulnerabilities of negative asymmetries. Integrative approaches that combine policy and technological measures at various levels are likely to make the world more secure. 相似文献
102.
103.
传统的基于数据包络分析的环境效率评价常常忽略投入、期望产出和非期望产出为离散型变量的可能性,从而无法精确处理现实中存在的具有整数特征的指标数据,一直以来影响着评价结果的精确性.本文以混合导向的整数DEA为基础,对超效率SBM模型进行拓展,构建了一种能够同时兼顾整数约束和非期望产出指标数据的超效率SBM模型,并在实例中采用搜索算法,对该模型进行求解并通过Bootstrap方法对结果进行修正.将每一个最优整数点与被评价决策单元之间的距离进行比较,可以找出最短距离所对应的最优整数点,即为其帕累托改进方向.该模型将为环境效率评价提供了适用范围更广泛的测度方法. 相似文献
104.
We present two experiments investigating the role of emotions concerning technological and natural hazards. In the first experiment, technological hazards aroused stronger emotions, and were considered to be riskier than natural hazards. No differences were found between the texts versus audio presentations. However, the presence of pictures aroused stronger emotions and increased the perceived risk. Emotions play a mediating role between hazard types and perceived risk, as well as between pictures and perceived risk. The second experiment adopted real‐world materials from webpages and TV. Emotions again play a mediating role between pictorial information and risk perception. Moreover, specific emotions were found to be associated with different types of action tendencies. For example, loss‐based emotions (e.g., fear, regret) tend to lead to prevention strategies, whereas ethical emotions (e.g., anger) lead to aggressive behavior. We also find that loss‐based emotions in the technical hazard scenario trigger more coping strategies (from prevention to retaliation) than in the natural hazard scenario. 相似文献
105.
Risk Perception in a Developing Country: The Case of Chile 总被引:2,自引:0,他引:2
In this work we characterize risk perception in Chile, based on the psychometric paradigm, exploring the difference between perceived social and personal risk. For this purpose, we conducted a survey including 54 hazards, 16 risk attributes, and 3 risk constructs. The survey, divided into four parts, was administered to 508 residents of Santiago, Chile. Using factor analysis, three main factors, which accounted for 80% of the sample's variance, were identified: factor 1, commonly called "Dread Risk" in the literature, explained 37% of variance; factor 2, "Unknown Risk," explained 28%; and factor 3, which we called "Personal Effect," explained 15% of the variance. On average, individuals perceived themselves as less exposed to risk and with more control and knowledge about them than the general population. OLS regression models were used to test the association of perceived risk with the three main factors. For social risk, factor 1 had the greatest explanatory power, while factor 2 had a negative sign. For personal risk, only factors 2 and 3 were significant, with factor 3 having the greatest explanatory power. Risk denial (defined as the difference between perceived personal and social risk) was associated with factors 1 and 2 only, with factor 2 having a negative sign. The difference between desired and actual regulation levels proved positive for all hazards, thus indicating that Chileans are dissatisfied with the current regulation level for all the hazards analyzed. The comparison of data at the aggregate and at the individual subject's level suggests that while the aggregate analysis overestimates the magnitude of the correlations it still reflects the tendency of the individual responses. 相似文献
106.
The Abu Sayyaf is an organization which has left a trail of mayhem and murder in the southern Philippines for more than a decade. It has gained international notoriety through several high profile mass kidnappings. This article looks at how the Abu Sayyaf has managed to survive and at times prosper despite the state's efforts to eradicate it. By using organizational analysis the paper demonstrates how the Abu Sayyaf has developed structures and processes which make it such a deadly force. The organization has succeeded in gaining considerable fit with the environment in which it operates. 相似文献
107.
LaKind Judy S. Ginevan Michael E. Naiman Daniel Q. James Anthony C. Jenkins Roger A. Dourson Michael L. Felter Susan P. Graves Carol G. Tardiff Robert G. 《Risk analysis》1999,19(3):375-390
The ultimate goal of the research reported in this series of three articles is to derive distributions of doses of selected environmental tobacco smoke (ETS)-related chemicals for nonsmoking workers. This analysis uses data from the 16-City Study collected with personal monitors over the course of one workday in workplaces where smoking occurred. In this article, we describe distributions of ETS chemical concentrations and the characteristics of those distributions (e.g., whether the distribution was log normal for a given constituent) for the workplace exposure. Next, we present population parameters relevant for estimating dose distributions and the methods used for estimating those dose distributions. Finally, we derive distributions of doses of selected ETS-related constituents obtained in the workplace for people in smoking work environments. Estimating dose distributions provided information beyond the usual point estimate of dose and showed that the preponderance of individuals exposed to ETS in the workplace were exposed at the low end of the dose distribution curve. The results of this analysis include estimations of hourly maxima and time-weighted average (TWA) doses of nicotine from workplace exposures to ETS (extrapolated from 1 day to 1 week) and doses derived from modeled lung burdens of ultraviolet-absorbing particulate matter (UVPM) and solanesol resulting from workplace exposures to ETS (extrapolated from 1 day to 1 year). 相似文献
108.
带有交易费用的证券投资最优策略 总被引:11,自引:5,他引:11
在假设证券价格服从几何布朗运动的基础上,运用随机最优控制理论,研究了在n 个风险证券金融市场中带有交易费用的证券投资问题,建立了带有交易费用的证券投资最优控制问题的数学模型.首先,简述了文中所涉及的随机最优控制理论,给出了值函数、效用函数和粘性解的定义.然后,在粘性解的意义下,推导出了交易策略有限和交易策略无限两种情况下值函数所满足的偏微分方程,该偏微分方程是由变分不等式描述的自由边值问题.最后,给出了两种情况下基于最优控制问题值函数的证券投资最优策略.本文得到的结果可以用于投资基金管理、金融风险管理等实际工作中,提高决策的科学性 相似文献
109.
110.
环境保护的宏观经济成本分析 总被引:3,自引:0,他引:3
本文讨论了环境经济成本问题,提出环境治理成本和环境机会成本两组概念,并用投入占用产出方法研究了宏观经济环境机会成本核算。 相似文献