严寒地区高速铁路混凝土基床聚氨酯保温特性试验研究

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.     

The heterogeneous relationship between board social ties and corporate environmental responsibility in an emerging economy

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.     

Measuring Inflation Anchoring and Uncertainty: A U.S. and Euro Area Comparison

We use several U.S. and euro‐area surveys of professional forecasters to estimate a dynamic factor model of inflation featuring time‐varying uncertainty. We obtain survey‐consistent distributions of future inflation at any horizon, both in the U.S. and the euro area. Equipped with this model, we propose a novel measure of the anchoring of inflation expectations that accounts for inflation uncertainty. Our results suggest that following the Great Recession, inflation anchoring improved in the United States, while mild de‐anchoring occurred in the euro area. As of our sample end, both areas appear to be almost equally anchored.     

Unfolding the impact of leadership and management on sustainability performance: Green and lean practices and guanxi as the dual mediators

This study aims to empirically evaluate the predictors that influence sustainability performance among manufacturing firms. Leadership and management, green and lean practices, and guanxi were examined to determine whether these predictors are directly and/or indirectly affecting sustainability performance; 160 valid responses were collected and partial-least-squares-structural-equation-modeling (PLS-SEM) was used to analyze the data. The results showed that leadership and management positively influenced green and lean practices and green and lean practices positively influenced sustainability performance. Leadership and management also positively influenced guanxi. Interestingly, leadership and management and guanxi do not exert a significant direct influence on sustainability performance. The findings contributed to the development of the resource-based-view theory further by empirically exploring the significance of leadership and management coupled with green and lean practices as competencies and capability to drive sustainability performance. The testing of the dual mediators' effects further added value to this study.     

城镇群空间结构与要素集聚

依据城镇化发展过程中要素空间集聚理论，展开区域经济发展的空间经济结构研究。通过城市引力、克鲁格曼指数计算，比较分析城镇群内部城市吸引力和城市产业分布的差异性，通过人口与生产空间分布集中度指标和不一致系数的测算，分析了山西省城镇群空间要素集聚效应。研究表明，山西省的城镇群规划与要素空间集聚趋势整体一致，城市间产业分工体系基本形成，城镇群的要素集聚效应明显，但人口与生产分布仍存在不一致性。研究认为，山西省城镇群发展应该继续明确各城市的产业分工和特色，引导劳动力和资本要素的合理流动，实现人口与生产空间分布的一致。     

Farm size and productivity growth in the United States Corn Belt

In recent decades, agricultural production in the U.S. has continued to shift to large-scale operations, raising concerns about the economic viability of small and midsized farms. To understand whether economies of size provided an incentive for the consolidation of production, the study estimates the total factor productivity (TFP) of five size classes of grain-producing farms in the U.S. Heartland (Corn Belt) region. Using quinquennial Agricultural Census data from 1982 to 2012 the study also compares TFP growth rates across farm sizes to gain insight into whether observed productivity differences are likely to persist. The finding of a strong positive relationship between farm size and TFP suggests that consolidation of production has contributed to recent aggregate productivity growth in the crop sector. The study estimates the extent to which sectoral productivity growth can be attributed to structural change versus other factors including technological change. The study also explores some tradeoffs associated with policies that raise the productivity of small versus large farms.     

Network structure,portfolio diversification and systemic risk

We investigate the effect of portfolio diversification on banking systemic risk, where the network effect is incorporated. We analyze three kinds of interbank networks, namely, random networks, small-world networks and scale-free networks. We show that the effect of portfolio diversification on banking systemic risk depends on interbank network structures and shock types. First, systemic risk increases first and then reduces with the increase of the level of portfolio diversification in the case of the individual shock. Second, in the case of the systemic shock, systemic risk reduces with the increases of the level of portfolio diversification. Third, banking systems with scale-free network structures are the most stable, and those with small-world network structures are the most vulnerable.     

Crisis leadership in economic recession: A three-barrier approach to offset external constraints

An economic recession is a type of crisis originated from external factors that may imperil an organization’s survival depending on the intensity and duration of the crisis. In peripheral European countries, such as Portugal, the recent financial crisis had devastating effects on various business activities. As a result, Portugal represents an important case study in examining how some corporate leaders have handled the economic recession successfully. I interviewed 20 corporate managers to capture their perceptions of the leadership traits and behaviors exhibited by their CEOs in guiding their companies through the recession. In economic recessions, negative constraints do not affect the most effective leaders, who instead erect barriers against the high-pressure conditions to create a supportive, positive work environment. In order to achieve maximum effectiveness, leaders must act as blocking agents against the negative social impacts of the economic crisis, including the fragility of trust in organizational life (i.e., a barrier against distrust), uncertainty of the future (i.e., a barrier against uncertainty), and toxic emotions (i.e., a barrier against toxic emotions).