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1.
孙英潮 《科技和产业》2021,21(2):238-242
基于严寒区京沈客专朝阳试验段路基基床的温度监测资料分析,研究不同厚度聚氨酯保温板对高速铁路路基混凝土基床温度变化特性影响.测试结果表明:①铺设聚氨酯保温板能够有效阻断严寒区环境与路基基床间的热量传递,保温效果与板厚相关;②地温大多数时间呈阳高阴低现象,同时阴、阳坡路基温差波动幅度随埋深逐渐减小;③基床表层阴、阳面各测点的温度变化起始时间一致,而阴面的冻结时间比阳面晚一个月.由此表明,保温板能够有效降低环境与混凝土道床之间的热交换,但是对路基阴、阳坡的影响存在差异.建议在严寒地区高速铁路路基阳、阴坡可以采取不同厚度的聚氨酯保温板,减小阴阳坡地温差异,保持季冻土路基温度变化稳定.  相似文献   
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Firms in emerging economies are faced with multiple, incompatible institutional forces in their environmental activities. Which of these forces will be dominant and instantiated within an organization is partly determined by the social relationships that a firm maintains with external actors. This paper investigates the relationship between board social ties and the level of environmental responsibility undertaken by firms in China, an emerging economy, by categorizing board social ties into three types in terms of the three isomorphic forces in the institutional field (coercive, normative and mimetic). Drawing on institutional and agency theories, using a sample of listed firms in environmentally sensitive industries, and a generalized least squares regression method, the results provide empirical evidence that ties that are linked to coercive and normative forces (i.e., political organizations and universities) are related to a higher level of environmental responsibility; however, those that are linked to mimetic forces (i.e., industrial peers) have a negative association with environmental responsibility, which is mitigated by CEO power. These findings suggest that the heterogeneous effects of board social ties on environmental responsibilities experienced by firms in a context of environmentalism are at an early stage.  相似文献   
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This study examines the impact of board directors with foreign experience (BDFEs) on stock price crash risk. We find that BDFEs help reduce crash risk. This association is robust to a series of robustness checks, including a firm fixed effects model, controlling for possibly omitted variables, and instrumental variable estimations. Moreover, we find that the negative association between BDFEs and crash risk is more pronounced for firms with more agency problems, weaker corporate governance, and less overall transparency. Our findings suggest that the characteristics of board directors matter in determining stock price crash risk.  相似文献   
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The open door policy of China’s economic reform since the 1980s has attracted heavy foreign direct investment (FDI) flows into China and especially to Guangdong (particularly the Pearl River Delta region, PRD) and induced significant economic growth during the past two decades. While there exist various classical theories of FDI in attempting to identify the determinants of FDI inflow and to explain the behavior of FDI flows, limited attention has been given from the perspective of agglomeration effects generated by a core-periphery (CP) relation.This paper intends to study the impacts of agglomerations on FDI inflows in the context of Krugman’s CP relation (1991) by investigating (1) the formation of a CP relation via gravity model analysis; (2) whether different types of industry FDI flows will respond differently in the CP-system, given agglomeration effects; and (3) whether FDI origin and firm scale matter in affecting FDI flows.A database consisting of a population frame of 37,742 firm-level manufacturing and services joint ventures investing in Guangdong in 1998 was used. Empirical results show that the agglomerations of the CP relation have affected FDI flow patterns. While both manufacturing and services FDI and sources of investment responded differently to the impacts, smaller firms were found more responsive to the CP-agglomeration settings regardless of FDI by industry type and by source. The significance and implications of the CP-system to further facilitate FDI in the region are discussed.  相似文献   
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董事会中心主义的确立,董事义务与责任体系的完备,使得对董事利益的保护成为公司经营管理效率提高的必要前提。如何建立符合中国实际的董事利益保护机制是摆在法学研究者面前一个紧迫而重要的课题。  相似文献   
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如何采用积极的方法解决中小企业融资难的问题已经迫在眉睫.本文从中小企业融资难的现状入手,重点分析融资难的原因,探寻解决途径.对中小企业融资难问题提出一孔之见.  相似文献   
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Among the economies with a Currency Board System (CBS), Hong Kong (HK) is probably the one with the largest and most developed financial sector, as well as the highest capital mobility. Hence, studying HK’s CBS is not only crucial to HK, but also important for the understanding of the modern CBS. This paper outlines the major monetary reforms in HK since the late 1980s. The impacts of these reforms and the 1997–1998 Asian Financial Crisis are then examined empirically. We focus on the differentials between the US and HK interbank interest rates. We assume the conditional-mean equation follows an autoregressive process and the conditional-variance equation follows a generalized autoregressive conditional heteroscedasticity process. This model captures the time-varying level and volatility of the differential. In light of the empirical results we provide an assessment of the reforms in HK.  相似文献   
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本文首先讲述了ITS中的2种通信技术——专用短程通信(DSRC)和蜂窝数字分组数据网(CDPD)的基本概念、工作原理及系统特点等,然后提出了一种基本这2种通信技术的先进公交系统,并对各个子系统的功能结构进行了描述。  相似文献   
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