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131.
在经济全球化的今天,发达经济体与新兴经济体之间的竞争日益激烈.首先,选取30个发达经济体和29个新兴经济体的基本要素指标、效率因素指标和创新因素指标,对发达经济体与新兴经济体竞争力孰强孰弱这一问题进行研究.其次,通过对各指标的计算和比较,得出新兴经济体竞争力仍比较弱的结论.最后,提出新兴经济体要想提升自身竞争力必须从政治制度、宏观经济运行、教育发展、基础设施建设等方面进行改进和完善的政策建议.  相似文献   
132.
《Risk analysis》2018,38(10):2029-2040
The Chippewa Ottawa Resource Authority monitors fish contaminants in Anishinaabe (Great Lake Native American) tribal fisheries. This article updates previously reported trends in two persistent bioaccumulative toxic (PBT) substances that are the primary contributors to consumption advisory limits for these fish: methylmercury (MeHg) and polychlorinated biphenyls (PCBs). Also, we report, for the first time, an analysis of nutritional benefit bioindicators and metrics in these same Upper Great Lakes fish harvests: selenium (Se) and omega‐3 fatty acids (PUFA‐3s). A novel risk/benefit quantification originally presented by Ginsberg et al. is reported here to characterize the tradeoffs between fatty acid benefits and toxic MeHg health outcomes. We also report a Se benefit metric to characterize the possible protective value against MeHg neurotoxicity based on Ralston et al. Congruent with Anishinaabe cultural motivations to consume fish from their ancestral fisheries, nutritional content was high in locally caught fish and, in some respects, superior to farmed/store‐bought fish. These Great Lakes fish still contained levels of PBTs that require careful education and guidance for consumers. However, the contaminant trends suggest that these fish need not be abandoned as important (both culturally and nutritionally) food sources for the Anishinaabe who harvested them.  相似文献   
133.
In the nuclear power industry, Level 3 probabilistic risk assessment (PRA) is used to estimate damage to public health and the environment if a severe accident leads to large radiological release. Current Level 3 PRA does not have an explicit inclusion of social factors and, therefore, it is not possible to perform importance ranking of social factors for risk‐informing emergency preparedness, planning, and response (EPPR). This article offers a methodology for adapting the concept of social vulnerability, commonly used in natural hazard research, in the context of a severe nuclear power plant accident. The methodology has four steps: (1) calculating a hazard‐independent social vulnerability index for the local population; (2) developing a location‐specific representation of the maximum radiological hazard estimated from current Level 3 PRA, in a geographic information system (GIS) environment; (3) developing a GIS‐based socio‐technical risk map by combining the social vulnerability index and the location‐specific radiological hazard; and (4) conducting a risk importance measure analysis to rank the criticality of social factors based on their contribution to the socio‐technical risk. The methodology is applied using results from the 2012 Surry Power Station state‐of‐the‐art reactor consequence analysis. A radiological hazard model is generated from MELCOR accident consequence code system, translated into a GIS environment, and combined with the Center for Disease Control social vulnerability index (SVI). This research creates an opportunity to explicitly consider and rank the criticality of location‐specific SVI themes based on their influence on risk, providing input for EPPR.  相似文献   
134.
Cooperation and competition are often viewed as incompatible, antagonistic forces, thus are operationalized as two extremes on a continuum. However, they can coexist and even enable each other, thus may be operationalized as orthogonal constructs. We address this contradictory phenomenon by developing a more granular view of the cooperation–competition paradox. Building on interdisciplinary research, we develop a three-dimensional model of relational space (fairness–opportunism, sharing–control, and engagement–rivalry), providing a novel tool with which to investigate the paradoxical interplay between cooperation and competition through eight operationalizable configurations. Using fuzzy-set qualitative comparative analysis (fsQCA), we test our model by assessing how different configurations of interfirm relationships influence the short- and long-term success of a sample of 217 firms. Our findings show that only two of the eight possible relational configurations are associated with firm success, one in both the long and short term, and the other in the short term only.  相似文献   
135.
采用由金属蒸汽真空弧离子源引出的强束流Zr,Zr+C离子对H13钢进行了离子束表面处理,借助划痕仪和摩擦试验机分别测量了经表面处理的H13钢的耐磨性和摩擦系数。研究结果表明:经Zr,Zr+C离子束处理的H13钢的耐磨性有所提高,摩擦系数明显降低,采用卢瑟福背散射谱(RBS)x射线衍射分析了注入层的成分,结构及影响其耐磨性的因素。  相似文献   
136.
面对3D打印技术发展进程中日益凸显的著作权法律问题,阐释3D打印数字模型在著作权法中的法律界定及保护范围,对3D打印数字模型究竟属于何种作品进行了探讨;指出3D数字模型到3D打印物的转换应为复制,以及3D数字模型和3D打印物的著作权侵权风险问题;提出应兼顾各方利益,对3D打印的著作权保护要在私人利益与公共利益之间寻找新的平衡.  相似文献   
137.
In this paper, we consider the problem of model robust design for simultaneous parameter estimation among a class of polynomial regression models with degree up to k. A generalized D-optimality criterion, the Ψα‐optimality criterion, first introduced by Läuter (1974) is considered for this problem. By applying the theory of canonical moments and the technique of maximin principle, we derive a model robust optimal design in the sense of having highest minimum Ψα‐efficiency. Numerical comparison indicates that the proposed design has remarkable performance for parameter estimation in all of the considered rival models.  相似文献   
138.
This continuing education course for professionals involved in all areas of clinical trials integrates concepts related to the role of randomization in the scientific process. The course includes two interactive lecture and discussion sections and a workshop practicum. The first interactive lecture introduces basic clinical trial issues and statistical principles such as bias, blinding, randomization, control groups, and the importance of formulating clear and discriminating clinical and statistical hypotheses. It then focuses on the most commonly used clinical study designs and the corresponding patient randomization schemes. The second interactive lecture focuses on the implementation of randomization of patients and drug supply through allocation and component ID schedules. The workshop practicum, conducted in small groups, enables students to apply the lecture concepts to real clinical studies. Flexibility was built into the workshop practicum materials to allow the course content to be customized to specific audiences, and the interactive lecture sessions can be stretched to cover more advanced topics according to class interest and time availability.  相似文献   
139.
针对当前Pro/E软件教学中的问题,提出将3D打印技术引入课程教学,以增强教学效果。给出了3D打印与Pro/E软件教学相结合的过程,并给出产品建模及3D打印教学的实例。实施结果表明,将3D打印技术引入到Pro/E课程,能提高学生学习兴趣,使学生掌握从产品设计建模到手板制作所需的各项技能。  相似文献   
140.
Attempts to replace pay‐as‐you‐go pension schemes with private funded systems came to a halt in Central and Eastern Europe after 2005. However, more recently, the region has witnessed two belated reformers: the Czech Republic and Romania. Both countries decided to partially privatize pensions despite the rising tide of evidence concerning the challenges associated with the policy. We argue that while part of the domestic political elite remained supportive of private funded pensions, the difficulties experienced by earlier reformers and reduced support from International Financial Institutions led to the adoption of small funded pension pillars. Such cautious attempts at privatization might become more common in the future as large reforms have proven politically unsustainable.  相似文献   
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