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31.
城市自生群落具有重要的生态服务功能与潜力,但因其外貌不被公众所接受而难以在城市公共空间中应用。将群落生态学和设计学相结合,探索一种介入栽培植物对城市自生群落进行改良,最终形成具有一定美学价值的植物群落的途径。实验以植物群落设计美学原理和种间竞争原理为依据,向已经演替1年的城市自生群落中引入63种栽培植物,按照分层的方式对群落进行改良。3年的观测结果表明,有61.9%的栽培植物可以在城市自生群落中定居并建立优势,能对76.7%的自生植物起到抑制作用,使55.8%的自生植物消失。相比城市自生群落,改良后的群落美观度提高29.4%,公众接受度提高24%,群落的物种丰富度提高至2.29倍。相比一般的人工植物群落,改良后的群落可以节约58.2%的建植成本,降低83.9%的浇水成本和67.8%的除草成本。实验证明改良设计是一种可行的群落设计途径,能有效提高群落的物种丰富度和美学价值,同时让自然参与群落设计过程,实现人与自然的合作。  相似文献   
32.
Using a sample of countries that require timely disclosures of insider trades, I investigate the effect of country‐level institutions that promote transparency on the extent to which aggregate insider trades predict market returns. I find that financial information transparency mitigates the predictive content of aggregate insider trades when markets are more likely to deviate from fundamentals (i.e., during market fads), and when there is greater co‐movement in stock prices. In contrast, there is some evidence that governance and investor protection mitigate the association between aggregate insider trades and future earnings surprises. Hence, holding constant the timely disclosures of insider trades, other capital market institutions play complementary roles in mitigating the informational frictions that give rise to the predictive content of aggregate insider trades.  相似文献   
33.
In state owned enterprises (SOEs), taxes are a dividend to the controlling shareholder, the state, but a cost to other shareholders. We examine publicly traded firms in China and find significantly lower tax avoidance by SOEs relative to non-SOEs. The differences are pronounced for locally versus centrally-owned SOEs and during the year of SOE term performance evaluations. We link our results to managerial incentives through promotion tests, finding that higher SOE tax rates are associated with higher promotion frequencies of SOE managers. Our results suggest managerial incentives and tax reporting are conditional on the ownership structure of the firm.  相似文献   
34.
This paper studies the impact of economic policy uncertainty on stock price crash risk using data from China. We develop a new index to measure Chinese economic policy uncertainty and find that economic policy uncertainty has a remarkable positive effect on stock price crash risk. However, the effect reverses later. The results also indicate that the positive effect of economic policy uncertainty on stock price crash risk is more prominent for state‐owned enterprises. Moreover, this effect is more prominent for firms with higher information asymmetry and firms with greater disagreement among investors, indicating that economic policy uncertainty affects crash risk through two mechanisms: managers’ concealment of bad news and investors’ heterogeneous beliefs.  相似文献   
35.
Theory predicts that market‐timing activities bias Jensen's alpha (JA). However, empirical studies have failed to find consistent evidence of this bias. We tackle this puzzle in a nested model analysis and show that the bias contains an exogenous market component that is unrelated to market‐timing skill. In a comprehensive empirical analysis of US mutual funds, we find that the timing‐induced bias in JA is mainly driven by this market component, which is uncorrelated with measured timing activities. Measures of total performance that allow for timing activities are virtually identical to JA, even if timing activities are present in the evaluated fund. Hence, we conclude that JA is a sufficient measure of total performance.  相似文献   
36.
应用双指耦合结构和枝节加载谐振器(Stub-loaded Resonator,SLR)实现了一款基于阶梯阻抗谐振器(Stepped Impedance Resonator,SIR)的滤波器。该滤波器具有3个通带,带外抑制较好,工作频段提高。通过调整阻抗比可调节第二、三通带的谐振频率;SLR结构能够增加通带数量;SLR结构和双指耦合结构均能改善滤波器的S参数。HFSS软件仿真表明,3个通带的中心频率分别为3.5 GHz、6.6 GHz、9.2 GHz,对应的分数带宽分别为5.7%、3%、2%,S11分别为-18 dB、-22 dB、-24 dB,通带内的S21分别为-1.8 dB、-1 dB、-1 dB。电路的测量结果与仿真结果较为吻合。该滤波器在5G通信的低频段具有应用前景。  相似文献   
37.
This paper contributes to the home (market) bias literature where administrative or political borders limit trade across borders. Home bias is well documented at the national and subnational level. To sort out macro (e.g., location characteristics) and micro (e.g., enterprise characteristics) factors behind home bias, we use small and medium‐sized enterprise (SME) data from Vietnam. Using the fractional multinomial logit model, we find that the proportion of SME sales outside of their home markets is positively associated with enterprise size, age, number of business association memberships and the distance of SMEs' most important supplier. In contrast, the proportion of SME sales to neighbouring provinces is negatively associated with the share of SME production for final consumption. Besides enterprise‐level frictions, market characteristics matter too. The proportion of SME sales to customers in their home markets is negatively associated with home or neighbouring provinces' governance quality, while the proportion of sales to customers in neighbouring provinces is positively associated with these areas' governance quality. These suggest that good governance frees SME resources for use in selling to less familiar markets.  相似文献   
38.
While the extant literature has examined the influence of controlling and non-controlling principals on the internationalization decisions of emerging market firms, heterogeneity among non-controlling principals is largely ignored. The risk characteristics of different groups of owners, shaped by their institutional environments, could contribute to the differences in their preferences for firm internationalization. In this paper, we draw insights from institutional theory and behavioral risk perspective to examine the risk propensities and risk perceptions of various non-controlling principals, such as pressure-resistant (FIIs and mutual funds) and pressure-sensitive (banks, insurance companies and lending institutions) institutional investors. Empirical results from a sample of 2364 unique Indian firms during the 2005–2014 time-period show that, after controlling for firm-level resources and capabilities identified in prior literature, the ownership share of different types of institutional investors is associated with firms’ international investments differently. While pressure-sensitive institutional investors, such as banks and insurance companies, are not supportive of foreign investments by firms, pressure-resistant institutional investors, such as FIIs and mutual funds, are supportive of this strategic decision. Furthermore, our results show that the family ownership in a firm (measured in terms of family shareholding) further lowers the preference of pressure sensitive institutional investors for internationalization, whereas family ownership positively moderates the pressure resistant investors towards internationalization.  相似文献   
39.
Family firms bear two types of agency costs, including type I and type II agency problems, in corporate environmental practices: (1) Outside executives at family firms hesitate to engage in environmental strategies, which can lead to drops in profits; (2) Controlling families employ opportunistically environmental management to achieve their interests. We argue that a primary cause for the agency problems lies on ineffective internal corporate governance at family firms, which can cause loss of managerial (or power) balance between outside executives and family executives. Our findings show that family firms with ownership and strategic control (FSC), which family executives and outside executives monitor and constrain each other, can achieve the highest environmental performance. Moreover, external controls, including product market competition and provincial environmental regulations, substitute effective internal control of FSC. The environmental performance premium of FSC is more prevalent when the production market competition is lower. Family firms with ownership, operational, and strategic control (FOSC) can achieve higher environmental performance within a province with more stringent environmental regulations.  相似文献   
40.
This article examines the impact of small and medium-sized enterprises' (SMEs) proactive environmental strategy on market performance through the mediating mechanism of environmental reputation. In addition, we investigate the potential moderating role of competitive strategies on the environmental reputation-market performance nexus. Data were collected from 223 SMEs. Using the hierarchical multiple regression analysis, the results show that a proactive environmental strategy positively enhances environmental reputation. Also, the influence of proactively environmental strategy on market performance is mediated by environmental reputation. In addition, our findings show the relationship between environmental reputation and market performance is greater for firms that adopt the differentiation strategy but not significant for firms adopting the low-cost and integrated strategies. Our study offers several theoretical and practical implications.  相似文献   
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