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排序方式: 共有3473条查询结果,搜索用时 15 毫秒
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.
This paper contributes to studies on dynamic capabilities (DCs) by showing that a neglected environmental contingency – i.e. the occurrence of a jolt – shapes the DCs–performance relationship. We focus on high-tech entrepreneurial ventures because these are the firms that jolts affect most; in so doing, we also advance the understanding of DCs in the entrepreneurship field. We argue that, in the aftermath of an environmental jolt, the high-tech entrepreneurial ventures that use internationalization and new product development capabilities to modify their resource configuration and regain environmental fit enjoy better performance. Econometric estimates on a sample of 340 Italian high-tech entrepreneurial ventures confronting the consequences of the global economic crisis that began in 2008 confirm that separately using these two DCs has a positive performance effect. This effect is stronger for relatively smaller ventures. Interestingly, despite synergies should arise from the combined use of the two DCs, we do not detect any superadditive effects.  相似文献   
4.
山东地方官对大刀会、拳会的宽容的政策与态度由来已久,早在甲午中日战争期间,官军就与大刀会形成默契,在共同缉捕盗匪方面取得显著成效,直至义和团在中外联合势力的绞杀下失败,在此期间,大刀会、拳会等名目的民间团体组织与官府的关系就处在一种半合作半破裂的游离状态,即这种宽容政策具有一定的延续性。就义和团运动而言,大刀会等民间会社势力仅仅是为义和团运动构筑的可能性力量而已,程度很高,却极不稳定,它们有待于官方的开掘、引导与锤炼及外力催逼,即官方对刀会、拳会的宽容态度与政策,以及西方列强、教会势力的威逼现实这两种因素,而前者更为重要。  相似文献   
5.
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   
6.
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   
7.
In dynamic contests, strategic momentum and psychological momentum potentially coexist, which makes it difficult to distinguish between the two. We employ the setting of professional tennis, which allows us to separate psychological from strategic momentum. In tennis, converting a break point potentially triggers both strategic momentum—due to a change in the relative position of the players—and psychological momentum—due to a change in the perception of the players. To distinguish between these two momentum types, we employ exogenously given interruptions. Interruptions are predicted to affect psychological momentum negatively, while leaving strategic momentum unaffected. Using 4930 game-by-game observations from 141 Grand Slam men’s single matches, we show that the breaking players’ probability of winning a game increases after converting a break point, which provides evidence for momentum. Moreover, we show that this momentum effect is negatively affected by an interruption. Thus, psychological momentum seems to be the main trigger leading to a performance increase after a converted break point.  相似文献   
8.
9.
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   
10.
Abstract

In the case where strength and stress both follow exponential distributions, this paper considers the maximum likelihood estimator (MLE) of the system reliability based on L ranked set sampling (LRSS). The proposed MLE is shown to have existence, uniqueness and asymptotic normality, and its asymptotic variance is obtained by the Fisher information matrix of LRSS. The values of asymptotic relative efficiencies show that the proposed MLE is always more efficient than the MLE using simple random sampling (SRS). However, the MLE using LRSS cannot be written in closed form. Therefore, the modified MLE is proposed using the technique replaced some terms in the maximum likelihood equations by their expectations. The newly modified MLE using LRSS is shown to be superior to the MLE using SRS. Finally, the proposed method is applied to a real data set on metastatic renal carcinoma study.  相似文献   
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