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1.
This study details how psychological, financial, and social factors shape employee deviant interpersonal behaviors during a pandemic. Data were collected with a survey of 372 front-line employees of hotels and analyzed with PLS-SEM. The findings showed social disconnectedness and perceived risk of unemployment leads to perceived isolation, which further creates depression in employees. The findings also showed that depression is positively related to employee deviance. Financial strain is a major cause of perceived isolation, depression, and deviant behaviors among front-line employees. Results also proved that social support reduces fear of isolation, depression, and employee deviance. This study provides guidelines that hotels need to understand the psychological stance of employees and design policies to overcome employee perceived fears and psychological disorders.  相似文献   
2.
为了研究网架结构的损伤检测方法,根据应变能密度理论,提出采用单元模态应变能密度差值作为网架结构损伤识别指标的方法,以损伤单元模态应变能密度差值的大小初步确定单元的损伤程度。分析了5种具有代表性的损伤工况,并在数值计算结果中引入了白噪声。结果显示,在一阶模态下,针对单损伤、多损伤和轻微损伤、严重损伤等不同损伤工况,损伤杆件的模态应变能密度差值均为高值。因此,该方法可以有效识别出网架结构的损伤位置,根据损伤单元的模态应变能密度差值大小初步确定单元的损伤程度,且在一定的噪声水平下具有较强的鲁棒性,对网架结构损伤识别具有参考价值。  相似文献   
3.
为了探索工程实际中水泥固化土的应力-应变关系及水泥土变形规律,参考岩石统计损伤本构模型的思路来构建水泥土统计损伤本构模型。假设水泥土微元强度服从Weibull概率密度分布,并引入初始损伤系数η,建立单轴压缩荷载下水泥土的统计损伤本构模型。根据应力-应变曲线峰值点的极值性进行模型参数求解,分析不同水泥掺量、不同龄期的水泥土累积损伤的扩展过程。通过对水泥土单轴压缩试验数据进行验证与分析发现,随着水泥掺量以及龄期的增加,水泥固化土模型参数η值增大,m值,F_0值减小,表明龄期和水泥掺量能够抑制水泥固化土损伤发展。新建立的水泥土统计损伤本构模型拟合效果较好,并能较好地反映水泥土的应变软化特性,可为水泥固化土的应力分布特点和变形规律研究提供一定参考。  相似文献   
4.
根据低应变反射波法检测高强度预应力混凝土管桩(PHC)桩身完整性的原理,通过具体工程实例对低应变反射波检测PHC管桩有关问题进行了分析探讨。  相似文献   
5.
Homogenization of agricultural landscapes affects ecological processes and biodiversity and can affect the community composition of ecosystem service providers. These effects can have particular impact in landscapes dominated by monocultures of pollinator-dependent tree crop plantations, which create both spatial and temporal homogeneity at the landscape scale. I looked for associations between the proportion of nearby unmanaged vegetation and potential wild pollinator groups collected within flowering almond orchards in two types of landscape. In the Complex landscape, characterized by a heterogeneous mosaic of multiple crops, semi-natural grassland and natural woodland, insect pollinator groups were not associated with unmanaged vegetation. In the Simple landscape, dominated by monoculture almond plantations, most pollinator groups showed positive relationships with the two unmanaged vegetation types (grassland and woodland). In particular, all wild bee and all but one hoverfly individual were found in remnant native vegetation patches within almond plantations, rather than within rows of almond trees. More research is necessary to identify how structural differences created in monoculture landscapes, between crops and the native vegetation they encroach on, influence ecological communities and the provision of ecosystem services.  相似文献   
6.
我国农业野生植物原生境面临着环境污染、人类农业生产、经济社会发展以及各类违法活动的侵蚀和破坏,建立原生境保护区是保护农业野生植物资源的重要途径之一。基于对当前威胁我国农业野生植物原生境面临的四大因素(自然灾害、农业活动、经济发展、违法活动)的系统梳理的基础上,探讨了现有农业野生植物原生境保护区建设的法规政策体系以及保护区建设现状和存在的主要问题,在此基础上提出了加强保护区建设的几点建议。分析结果表明,当前我国农业野生植物保护区建设存在的主要问题包括:保护区土地权属界定、保护区建设内容限定过窄、忽视保护区管理机构能力建设、对保护区周边农民权益保护不够。为了提高保护区建设工作,文章建议相关部门应该重视以下几个问题:统筹协调行业部门之间的权属差异,重视农业野生植物异位保存工作,修订完善保护区建设技术规范,兼顾保护区民众利益。  相似文献   
7.
Factors affecting subjective well-being and their gross effect measurement have been widely studied. However, how people derive utility from these factors has not been fully explored. This article provides a way to decompose the gross effect of major determinants on life satisfaction into direct and indirect effects and make inference for the latter. Because the indirect effect is nonlinear in parameters associated with different models in an equation system, it creates a problem in estimating the standard error. Besides, the categorical nature in survey data further introduces bias to the covariance estimation even asymptotically. To address these issues without knowing the form of heteroskedasticity under the null hypothesis, we propose to extend the wild bootstrap procedure in this particular context. Its robustness against various data properties is validated via several simulation experiments. Using three recent waves of World Values Survey, we find that the relative importance of life control has significantly increased recently, and endowing citizens with the right to enjoy their freedoms and liberties is a more effective policy in raising life satisfaction than promoting national income.  相似文献   
8.
We develop two models of the relationships between emotional intelligence (EI), job insecurity, and psychological strain. The moderation model suggests that EI reduces psychological strain by helping individuals cope with job insecurity when it arises. The mediation model suggests that EI reduces psychological strain by enabling individuals to conserve resources, thereby reducing their experience of job insecurity. Our results, based on a sample of 232 real estate agents, show that job insecurity mediates the relationship between EI and psychological strain. Contrary to what the moderation model suggested, the positive relationship between job insecurity and psychological strain was found to be stronger when EI was higher. Overall, the results provide more nuanced insights into the role of EI in psychological strain.  相似文献   
9.
姜劲松  邵振  田侃 《价值工程》2012,31(26):277-280
随着现代工业社会进程的逐渐深入,倚靠传统农业社会发展起来的中药材资源面临着严峻的挑战,特别是野生中药材资源的枯竭和衰亡,更应当引起高度的重视。探讨在现代法治社会视域下如何保护与合理利用野生中药材资源,不啻为有效解决该问题的方法之一。  相似文献   
10.
We examine the quantile serial dependence in crude oil prices based on the Linton and Whang’s quantile-based portmanteau test which we improved by means of quantile wild bootstrapping (QWB). Through Monte Carlo simulation, we find that the quantile wild bootstrap-based portmanteau test performs better than the bound testing procedure suggested by Linton and Whang. We apply the improved test to examine the efficiency of two crude oil markets – WTI and Brent. We also examine if the dependence is stable via rolling sample tests. Our results show that both WTI and Brent are serially dependent in all, except the median quantiles. These findings suggest that it may be misleading to examine the efficiency of crude oil markets in terms of mean (or median) returns only. These crude oil markets are relatively more serially dependent in non-median ranges.  相似文献   
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