生态挡土墙的特点及适用范围探析

在生态环保、节能降耗日渐成为趋势的新时期,各类生态挡土墙都得到不同程度的应用。文章指出了普通生态挡土墙的生态特点及适用范围,重点分析了后垂型砌块挡土墙和溢水孔砌块挡土墙这类砌块加筋土挡土墙的生态特点和技术特征。     

Scale And Scope In Technology: Large Firms 1930/1990

We examine historical empirical patterns of change in corporate. technological scale and scope. Much literature on scale and scope by business and economic historians has conflated product markets and technology together. However, given the technologically complex environment of the late twentieth century, the relationship between scale and scope in production and products is not simple, and conflated discussions may be naive. Consequently we have two aims. Firstly, we wish to see if technological scale and scope follow the historical pattern of broader notions of scale and scope. Secondly, given increasing technological complexity, we consider whether the nature of corporate technological scope has changed over time.

Using data drawn from the University of Reading's patents database, we examine the technological activities in 32 of the world's historically largest patenting firms over the period 1930 to 1990. Shin-sham analyses based on panel-data regressions examine the different influences on technologicascope over time. A technological trend closely resembling that of broader notions of scale to scope is observable in most of the sectors. although it does not proceed uniformly. We also find, that whilst increases in corporate technological scope through diversification are not particularly linked to technological relatedness in recent times, they are periodically influenced by the rise of pervasive, fast-growing new technologies.     

Arcs of carbon awareness in the value chain and their antecedents

This study examines the patterns and antecedents of firms' value chain greenhouse gas emissions (VCGGE) awareness. Drawing on a sample of 1,322 firms from multiple countries and industries, we use cluster analysis to first evaluate how well firms' VCGGE awareness patterns match traditional value chain integration patterns, identified by prior literature. We then examine how well internal indicators of greenhouse gas emissions (GGE) management predict advanced VCGGE awareness. Our study indicates that VCGGE patterns partially match traditional value chain integration patterns and that firms' VCGGE awareness is much higher for their upstream than downstream activities. Moreover, our findings show that the internal adoption of GGE management is a significant predictor of advanced awareness of VCGGE. Overall, we find that most firms have limited awareness about the magnitude of their VCGGE, suggesting that many opportunities to reduce these emissions, especially in the downstream value chain, remain unexplored.     

地方官员变更对企业投资影响的空间范围——基于政企联盟重建的逻辑分析

文章运用政企联盟重建这一理论对政企双方行为进行分析,完整的解释了我国官员变更对企业投资影响所呈现出的区域、层级及所有制特征,利用2003-2012年沪深两市上市企业面板数据进行了实证研究。结果表明：（1）官员变更对企业投资的影响呈现区域性、层级性特征。省委书记变更省委书记变更不会对全省的企业投资产生显著影响,但导致省会城市的企业投资明显减少,对省会城市影响高于非省会城市影响;市委书记变更对市区企业投资影响显著高于对县区企业影响。（2）省委书记与国有企业建立的紧密联盟会突破本地性特征,延伸到外地,而省委书记与民营企业建立的默契联盟则具有明显的本地性。文章研究丰富了官员变更对企业投资影响的相关文献。     

“一带一路”倡议与企业国际化程度——基于制造业上市公司的证据北大核心

本文将“一带一路”倡议视为一项准自然实验,基于2007~2020年A股制造业上市公司数据,运用双重差分模型探究“一带一路”倡议对企业国际化程度的影响。研究发现,“一带一路”倡议能够显著提升企业国际化程度。作用机制研究发现,“一带一路”倡议可以通过缓解融资约束和提升研发强度提升企业国际化程度。异质性检验发现,“一带一路”倡议能够提升大规模企业和中小规模企业国际化程度,且对中小规模企业国际化程度的提升效应更加明显;相对于内向型城市节点,“一带一路”倡议显著提升了外向型节点城市企业国际化程度。进一步地,“一带一路”倡议能够显著促进企业国际化范围的扩张。