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1.
Using an ARDL model for a panel of 15 OECD countries, this work analyses the impact that FDI, both jointly and by sector, has on CO2 emissions. The findings reveal that these countries are yielding to the pressure on the trade sector. Unexpectedly, gross fixed capital formation shrink pollution, excluding in the mining sector. With findings supporting the Pollution Haven Hypothesis, policymakers must pay attention to FDI inflows, ensuring that FDI place high importance on the transfer of green technologies to improve the efficiency. These goals could be achieved through an increase in the stringency of environmental laws within the host countries, especially the ones related to FDI.  相似文献   
2.
Uniform designs are widely used in various scientific investigations and industrial applications. By considering all possible level permutation of the factors, a connection between average centered L2-discrepancy and generalized wordlength pattern for asymmetrical fractional factorial designs is derived. Moreover, we present new lower bounds to the average centered L2-discrepancy for symmetrical and asymmetrical U-type designs. For illustration of the theoretical results, the lower bounds for symmetrical and asymmetrical U-type designs are tabulated, and numerical results indicate that our lower bounds behave well and can be recommended for use in practice.  相似文献   
3.
目前有许多研究将两阶段DEA模型应用到科技创新活动当中,一般将创新活动分为研发和转化两个阶段,为了进一步探讨不同转移转化方式下科技成果的转化效率以获得更多的详细信息,本文拓展了传统的两阶段DEA模型,考虑了嵌套并联结构的两阶段网络DEA模型,将科技创新活动分为科技成果研发阶段和科技成果转化阶段,并将科技成果转化阶段分为内部转化和外部转化两个并联子系统。本文选取14家中科院院属单位作为被评价对象,应用加权加法分解方法计算整体效率和各阶段子效率。通过将本文模型与传统两阶段模型进行对比发现,传统模型会低估科技成果转化效率。结果表明:整体科技创新效率均值偏低,科技成果研发效率均值高于科技成果转化效率均值,科技成果转化效率仍有很大的提升空间。科技成果转化阶段中内部转化效率普遍较高但是外部转化效率普遍较低,较低的外部转化效率是导致科技成果转化效率低下的主要原因。最后,本文将所有被评价单位分为四类机构,分析提高科技创新效率的实现路径,可以通过重点突破模式和渐进突破模式来实现整体效率的提高。  相似文献   
4.
为了解大学生在新型冠状病毒肺炎疫情防控期间的焦虑状况,采用汉密顿焦虑量表(HAMA),对四川、云南、重庆三省(直辖市)的3 178名大学生进行在线问卷测试。结果发现:新冠肺炎疫情防控期间大学生焦虑水平高于常模,并且与大学生的性别、就读学历层次、就读学科、每日上网时间等存在显著相关性。其中,28.48%的大学生还可能有严重焦虑;女性、专科层次、尚不清楚就读学科的大学生群体焦虑水平更为明显;精神性焦虑是新冠肺炎疫情防控期间大学生焦虑的主要特质;每日上网时间与大学生精神性焦虑水平呈显著正相关。在公共卫生事件突发时期,应积极关注大学生的心理健康状态,采取针对性措施加以有效疏导和干预,促进其心理健康发展。  相似文献   
5.
Supporting healthy lifestyle behaviours is a key aspect of preventing type 2 diabetes which disproportionately affects disadvantaged groups from a younger age. Formative participatory research was undertaken to design a program for young Aboriginal people in a remote town in North West Australia with a high level of health needs and relatively few prevention initiatives. Focus groups and advisory discussions with Aboriginal community members were used to determine the nature of the program. The need for a comprehensive program was consistently expressed and limited healthy lifestyle knowledge and difficulties with healthy eating influenced by food environments were noted to be important. With guidance from the Derby Aboriginal Health Service, findings were integrated with previous international research evidence to develop a program tailored to local Aboriginal people aged 15–25 years and refine it after piloting. This 8-session program, ‘Maboo wirriya, be healthy’ involved an education component consistent with the US Diabetes Prevention Program and practical activities including group exercise. Changes to program structure and documentation were made after piloting for future use. The community-directed approach used in this study is vital to ensure relevance of localised chronic disease prevention programs in a range of settings.  相似文献   
6.
7.
Adverse childhood experiences might have long-lasting effects on decisions under uncertainty in adult life. Merging the European Survey on Health, Ageing and Retirement with data on conflict events during the Second World War, and relying on region-by-cohort variation in war exposure, we show that warfare exposure during childhood is associated with lower financial risk taking in later life. Individuals who experienced war episodes as children hold less – and are less likely to hold – stocks, but are more likely to hold life insurance, compared to non-exposed individuals. Effects are robust to the inclusion of potential mediating factors, and are tested for nonlinearity and heterogeneity. Moreover, we provide evidence of hedonic adaptation to war, as high and low intensity of war exposure have comparable long-term effects. We also document that war exposure in childhood increases sensitivity to financial uncertainty since exposed-to-war individuals are less likely to hold stocks after periods of high volatility. Finally, we shed light on the most likely mechanism in the relationship between war exposure and financial risk taking – i.e., enhanced sensitivity to uncertainty – and we show that preferences, and not beliefs, channel this relationship.  相似文献   
8.
Abstract

This paper considers the optimization problems for a consecutive-2-out-of-n:G system where n is considered to be fixed or random. When the number of components is constant, the optimal number of components and the optimal replacement time are discussed by minimizing the expected cost rates. Furthermore, we focus on the above discussions again when n is a random variable. We give an approximate value of MTTF and propose the preventive replacement policy, respectively.  相似文献   
9.
鉴于信用证具有比较强的收汇保障的性能和贸易融资功能,因此也一直是我国出口企业贸易结算的首选,使用率高居90%。但是近年来,其结算的“霸主”地位不断弱化,并由此对我国外贸出口产生了较大的不利影响。本文探讨了其中具体的原因及影响,并辅以对策。  相似文献   
10.
The goal of this study is to provide a cross-lagged examination of the relationships between engaging leadership, job resources and employee work engagement. We propose a mediation model and we postulate that engaging leadership can increase perceptions of three specific job resources (i.e. autonomy, support from colleagues and opportunities for learning and development) which theoretically correspond to the three facets of engaging leadership (i.e., inspiring, connecting and strengthening, respectively). Subsequently, in keeping with the extant body of Job Demands-Resources (JD-R) research, we link job resources to employee work engagement. Our hypotheses were tested on data collected at two time-points – T1 (N = 759) and T2 (N = 273) –from employees working for a hotel chain in the Netherlands. In line with our expectations, engaging leadership showed a significant cross-lagged relationship with autonomy and support from colleagues, but did not predict learning opportunities and work engagement across time. While we formulated specific hypotheses, we also tested reversed causation relationships. We found no direct effect from engaging leadership on employee work engagement, however, the reversed effect was significant; employee perceptions of engaging leadership were shaped by their own engagement experiences. Importantly, engaged employees at T1 reported more job resources at T2. By providing a cross-lagged examination of our model, we showed that engaging leaders as well as employees’ positive affective state of being engaged, are essential to shaping a resourceful work context. A comprehensive view on the triggers and outcomes of work engagement and engaging leadership is needed, as the traditional unidirectional cause-effect rationale fails to explain how these concepts relate to one another and to employee experiences of job resources.  相似文献   
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