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61.
李洋溢  袁通  秦鲜卓 《科技和产业》2021,21(11):326-332
受地形地质条件、工程经济以及勘察深度等因素的制约,山岭重丘区隧道不可避免地会受到各种不良地质灾害的影响.为解决隧道穿越洞口浅埋段滑坡体的施工安全问题,以乐业至百色高速公路永乐隧道工程为研究背景,针对其地形地质条件及滑坡体情况,结合洞内变形与滑坡体变形相互作用机理,对隧道穿越洞口浅埋段滑坡体施工关键技术进行研究,并针对性地提出"洞外加固处治+洞内严格控制沉降"的综合处治方案.实践结果表明,本隧道工程穿越洞口浅层滑坡体的施工过程安全顺利,采取的施工控制措施方案实施效果良好.  相似文献   
62.
We assess the conditional relationship in the time-frequency domain between the return on S&P 500 and confirmed cases and deaths by COVID-19 in Hubei, China, countries with record deaths and the world, for the period from January 29 to June 30, 2020. Methodologically, we follow Aguiar-Conraria et al. (2018), by using partial coherencies, phase-difference diagrams, and gains. We also perform a parametric test for Granger-causality in quantiles developed by Troster (2018). We find that short-term cycles of deaths in Italy in the first days of March, and soon afterwards, cycles of deaths in the world are able to lead out-of-phase US stock market. We find that low frequency cycles of the US market index in the first half of April are useful to anticipate in an anti-phasic way the cycles of deaths in the US. We also explore sectoral contagion, based on dissimilarities, Granger causality and partial coherencies between S&P sector indices. Our findings, such as the strategic role of the energy sector, which first reacted to the pandemic, or the evidence about predictability of the Telecom cycles, are useful to tell the history of the pass-through of this recent health crises across the sectors of the US economy.  相似文献   
63.
Research Summary: The role of homophily in CEO appointments at the largest corporations is an important subject in corporate governance. This subject is particularly important in a country like India where a multitude of religions, castes, and communities form its social fabric. We test for the role of homophily in professional CEO appointments in India by empirically examining the preference for same caste/religion CEOs by the largest firms. Using a unique dataset, assembled by detailed identification of castes/religions from family names and counterfactuals obtained through the Coarsened Exact Matching technique, we find that caste/religion plays a crucial role in CEO selection as a source of information (positive discrimination). The evidence is not consistent with its use to pursue taste‐based preferences (negative discrimination). Managerial Summary: We test for the role of homophily in the appointments of CEOs in India by empirically examining the preference for same caste/religion CEOs by the largest firms. We find that caste/religion plays an important role in CEO selection, i.e., as a form of information or “positive discrimination.” The evidence is not consistent with its use to pursue taste‐based preferences or “negative discrimination.”  相似文献   
64.
董恺  岳书铭 《科技和产业》2019,19(9):134-138
由于基层政府长期存在财力事权上的不均衡,我国基层地区义务教育供给存在着差距。2001年的"以县为主"的县统筹财政制度开始实行,义务教育的负责主体变成了县级政府。借助2002年到2016年的山东省县级数据,运用泰尔指数作为分析工具,结合此期间山东省出台的教育改革措施,分析其对于缩小义务教育差异的影响。研究发现,政策制度仅仅改善了中等收入县级地区之间的差距,对于高收入和低收入地区并没有太好的效果,就目标而言,由于县级各地区上经济实力和义务教育规模的固有差距,导致无法取得理想中的效果。  相似文献   
65.
《Business Horizons》2019,62(5):603-613
This study integrates insights from Self-Determination Theory and Boundary Theory to present scenarios on how flexible workplace designs can trigger multiple motivational processes underlying gendered work/nonwork integration behaviors, and how these affect work/life conflict. We disentangle processes underlying work engagement and work/life conflict, explaining the paradoxical outcomes found with regard to gender inequality in terms of work/life performance, satisfaction, and health. Policy makers and organizations need an increased understanding and a reconceptualization of these issues, realizing that the ideal worker does not exist. Instead, a long-term perspective is needed in order to truly realize the potential benefits of flexible workplace designs for all stakeholders. Organizations need to take responsibility for preventing individual workers’ depletion and stimulating the regeneration of workers’ resources.  相似文献   
66.
This study examines the previously unexplored mediating role of work engagement in the link between creative work involvement and the relational resources embedded in supervisor‐follower exchanges. We studied three relational resources inherent to the exchanges between followers and their supervisors: trust in supervisor, goal congruence, and relationship informality. Data were captured from IT professionals working at four well‐established IT companies in Ukraine. The findings show that relationship informality and goal congruence positively affect employees' creative work involvement, yet these effects are less pronounced when controlling for work engagement. The significance and implications of these findings for research and practice are discussed. Copyright © 2016 ASAC. Published by John Wiley & Sons, Ltd.  相似文献   
67.
为了实现产品生产阶段到服务阶段业务与数据的有效集成,从业务层和数据层对制造服务系统中的大修维护维修(MRO)与企业资源计划(ERP)的集成过程进行了建模与分析,对ERP与MRO系统之间的业务过程和信息交互过程进行了分析,建立了二者的业务集成框架模型,分析了ERP与MRO系统的数据结构转换过程,提出了二者数据集成模型。应用Web Services完成了ERP与MRO的系统集成开发,包括服务BOM集成、备品备件管理集成等。研究结果实现了制造和服务阶段关键产品数据信息的集成与反馈,打通了从制造到服务阶段的数据传递与集成,对进一步研究复杂产品生命周期管理的信息集成具有一定的借鉴意义。  相似文献   
68.
[目的]以河南省中牟县为研究对象,通过评价中牟县低碳农业发展水平,试图探索适合中牟县低碳农业的发展道路,并为当地低碳农业发展提供参考依据。[方法]文章采用统计数据分析法、调查统计分析法以及层次分析法。搜集分析2005~2015年中牟县低碳农业相关数据,构建低碳农业系统发展评价指标体系,得出中牟县低碳农业历年综合得分。[结果]中牟县低碳农业发展呈逐年上升趋势,2005~2015年年均增长率14.50%。其中,农业社会因素、农业经济因素发展得分高于低碳农业综合得分,年均增长率分别为23.90%、25.20%,但农业资源和环境方面发展缓慢,年增长率分别为2.30%、-1.40%。[结论]中牟县低碳农业呈现稳固上升发展态势。2005~2015年中牟县低碳农业数据分析表明,农业社会和经济系统的发展是中牟县低碳农业发展的重要推动力;而农业资源的投入、农业环境问题已成为中牟县低碳农业发展的主要阻碍制约因素。  相似文献   
69.
We document that Chinese stock returns exhibit early-in-the-week effects opposite-signed to those observed worldwide. The period of analysis is 2001–2016. Dominated by individual investors, Chinese stock markets offer unique out-of-sample insight regarding the source of weekday seasonality, ascribed elsewhere to institutional investors’ trading patterns. High returns to the market and to small, speculative stocks early-in-the-week pose a refuter to the mood explanation for the conventional (negative) Monday effect. A battery of tests suggests that the patterns in the Market, SMB, and RMW factors are jointly associated with Chinese individual investors whose demand is tilted towards small, speculative stocks. Our findings point to a potential role of dominant investor type in driving weekday patterns and the RMW premium.  相似文献   
70.
针对机载三维音频应用的实时性需求,提出了一种基于单耳相对头相关传递函数和改进型混响模型的机载三维音频快速实现方法,在较传统实现方式性能无明显下降的情况下降低了80%的计算量。对提出的算法在F-16战斗机模拟强噪声环境下进行相关主观试听实验,同时在某型飞机音频系统中实验验证。实验结果表明,所提方法在实时处理3路三维音频时,三维音频方位分辨精度在5°以内,可满足实际机载平台使用需求。  相似文献   
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