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1.
冷战结束十年以来 ,美国的对华政策依然摇摆不定。之所以如此 ,是因为十年来美国视中国为敌还是为友 ,或者非敌非友 ,至今还未定性。而美国难于在其国际政治安全战略中给中国定性的原因 ,则与以下的三个层次密切相关 ,即美国的国内政治层次、中美关系的发展层次和全球层次。  相似文献   
2.
To study the homogeneity and influences on scientists'perspectives of environmental risks, we have examined similarities and differences in risk perceptions, particularly regarding nuclear wastes, and policy preferences among 1011 scientists and engineers. We found significant differences ( p 0.05)in the patterns of beliefs among scientists from different fields of research. In contrast to physicists, chemists, and engineers, life scientists tend to: (a)perceive the greatest risks from nuclear energy and nuclear waste management; (b)perceive higher levels of overall environmental risk; (c)strongly oppose imposing risks on unconsenting individuals; and (d)prefer stronger requirements for environmental management. On some issues related to priorities among public problems and calls for government action, there are significant variations among life scientists or physical scientists. We also found that–independently of field of research–perceptions of risk and its correlates are significantly associated with the type of institution in which the scientist is employed. Scientists in universities or state and local governments tend to see the risks of nuclear energy and wastes as greater than scientists who work as business consultants, for federal organizations, or for private research laboratories. Significant differences also are found in priority given to environmental risks, the perceived proximity of environmental disaster, willingness to impose risks on an unconsenting population, and the necessity of accepting risks and sacrifices.  相似文献   
3.
The seriousness of computer hacking is not exaggerated, it is far worse than that. The computer hacker has attained the status of myth; society associates all computer crime with a mythical perpetrator that bears no resemblance to reality. This paper will argue that in the early stages of the myth the computer hacker was regarded as a highly skilled but mentally disturbed youth who has an unhealthy association with computers. The new reality of electronic commerce resulted in pressures that culminated in the computer hacker becoming regarded as a dangerous criminal. A thorough analysis of the statistics will demonstrate that the majority of computer intruders are neither dangerous nor highly skilled, and thus nothing like the mythical hacker.  相似文献   
4.
伊朗核危机与中国石油安全   总被引:1,自引:0,他引:1  
伊朗核危机中,伊朗凭借其地缘、能源“优势”大力开展“政治性能源外交”,与美国展开“能源博弈”,这一状况将对中国的石油安全造成一定的影响。为了突破能源“困境”,中国需要做出一些“战略性”的政策调整。  相似文献   
5.
特许经营在世界各地强劲的发展着 ,它既是市场高度化的结果 ,又是促使市场进一步发展的重要条件。它的主要优势在于 :1 对中小投资者来说具有低风险和低门槛进入的便利。 2 对主导企业来说是实现低成本扩张、规模效益以及加大无形资本边际回报的途径。 3 对这种经营方式本身来说它能随着IT行业的迅猛发展 ,可以与电子商务形成优势互补 ,所以特许经营将成为经营方式未来的选择  相似文献   
6.
This paper documents and analyzes how landholders managed to uplift status of their neighborhood from hazard land as designated by the 1978 master plan to a regularized residential settlement through land regularization in Dar es Salaam city. Specifically, explores policy framework governing land regularization and how the local community explored the opportunities it offers. Documents the local community planning and land regularization processes undertaken focusing on land use planning, drainage construction, and cadastral survey and discuses how financial resources were raised, trust was built as well as factors which sustained community involvement towards meeting their interests of securing tenure. The paper also, draws challenges facing land regularization policy and recommends areas for further interventions commensurate with the human dimension challenges in securing tenure.Underlying community involvement, those aspects of community, which have been connected to the idea of social capital namely existence of committed leadership in land development matters, embracing mechanism for participatory decision making process and educational background to local leaders were particularly important in determining success for the case. Others include economic ability to contribute, high proportion of landholder settlers, land conflict task force formulation, local consensus to solve commonly felt problems, existence of strong community organization, and unwritten norms put in place to regulate individual behavior in building construction. Weak legal recognition of informal settlement, lengthy and bureaucratic procedures in planning and approval of regularization plans, weak knowledge on land management matters, short-term title deeds with low financial betterments, political popularity are identified critical challenges.Some of recommendations put forward include formalization of the grass-roots role in decision-making, decentralizing some of land development control functions to sub-ward leaders and training the same in basic land management matters. Others include definition of norms; by-laws and government facilitation of informal land parceling. Besides community support should be sought so as to create partnership in the promotion of security of tenure in informal areas. The study concludes that, unless land development activities ongoing in informal settlements are closely monitored and regulated as the settlement grow, it will be too costly socially and economically to retrofit once the settlement have identified.  相似文献   
7.
本文简要地综述了高效液相色谱与核磁共振联用技术,并列举了该技术在药物、天然产物以及异构体研究中的应用。  相似文献   
8.
基尼系数合意值和警戒线的探讨   总被引:5,自引:1,他引:4       下载免费PDF全文
洪兴建 《统计研究》2007,24(8):84-87
 近年来,很多学者对基尼系数的经验法则尤其是警戒线提出了质疑。本文首先分析了收入分配的合意类型,然后依据相对贫困、贫富差距及中等收入者的收入份额三个指标来界定合意的收入分配,最后根据合意收入分配确定基尼系数的合意值和警戒线。本文结论表明,0.3—0.4可以被认为是基尼系数的合意值,0.4作为基尼系数警戒线也是比较合理的。  相似文献   
9.
This paper presents the results of a study that identified how often a probabilistic risk assessment (PRA)should be updated to accommodate the changes that take place at nuclear power plants. Based on a 7-year analysis of design and procedural changes at one plant, we consider 5 years to be the maximum interval for updating PRAs. This conclusion is preliminary because it is based on the review of changes that occurred at a single plant, and it addresses only PRAs that involve a Level 1 analysis (i.e., a PRA including calculation of core damage frequency only). Nevertheless, this conclusion indicates that maintaining a useful PRA requires periodic updating efforts. However, the need for this periodic update stems only partly from the number of changes that can be expected to take place at nuclear power plants–changes that individually have only a moderate to minor impact on the PRA, but whose combined impact is substantial and necessitates a PRA update. Additionally, a comparison of two generations of PRAs performed about 5 years apart indicates that PRAs must be periodically updated to reflect the evolution of PRA methods. The most desirable updating interval depends on these two technical considerations as well as the cost of updating the PRA. (Cost considerations, however, were beyond the scope of this study.)  相似文献   
10.
加强证券监管和完善证券监管的法制建设现已成为各国共识。我国的证券市场经过二十年的发展, 在证券监管法制建设方面虽已取得可喜的成绩, 但仍面临着许多问题和挑战。本文现就我国证券监管的法制建设有关问题做些思考。  相似文献   
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