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991.
We analysed a county‐level data set of single‐season rice yield and daily weather outcomes in China to examine the effects of temperature on China's rice sector. We found that rice yield exhibited highly nonlinear responses to temperature changes: rice yield increased with temperature up to 28°C and decreased sharply with higher temperatures. Holding current growing seasons and regions constant, average rice yield in China is projected to decrease by 10–19 per cent by 2050 and 11–33 per cent by 2070 due to future warming under the global climate models HadGEM2‐ES and NorESM1‐M. These results imply that future warming poses a major challenge for Chinese rice farmers and that the effectiveness of adaptations will depend on how well they reduce the negative temperature impacts on rice yield because of very hot days.  相似文献   
992.
山区超短波无线电通信链路的设计   总被引:1,自引:0,他引:1  
叙述了山区超短波无线电通信电路设计的有关技术问题,给出了山峰绕射模式的传输损耗计算方法、绕射位置判断的方法及计算程序流程图,最后通过实例说明此方法的计算精度。  相似文献   
993.
We analyze the contents of print ads in the motion picture industry (e.g., number of reviews quoted in the ad, the presence of a top reviewer, size of the ad, star, director, etc.). We find that external validation (a recommendation by a top reviewer) is more important to revenues than the informative content of the ad.  相似文献   
994.
为了考察改进苯酚-硫酸法测定保健品口服液中粗多糖提取方法的可行性,以某保健品口服液为样品,对采用苯酚-硫酸法测定粗多糖含量时的多糖的不同提取条件与测定进行一个较为详细、系统的研究。结果表明:样品经改进提取条件后测定,试验结果表明有良好的线性关系,精密度RSD值为0.69%,稳定性良好,平均加标回收率为101.0%。该方法改进后提高了该实验的精密度和准确度,重现性高,并使结果更加可靠和稳定。  相似文献   
995.
随着环境恶化和生活方式改变,高血脂、冠心病和癌症等发病率不断上升。我国2/3人口以稻米为主食,功能性稻米的"食疗""食补"已成为研究热点。黑米素有"世界米中之王"的美誉,其活性成分花色苷具有抗氧化、降血脂、抑癌抗癌和抑菌抗炎抗过敏等生理功能。本文对黑米花色苷的功效进行了简述。  相似文献   
996.
This article explores the impact of service quality on idiosyncratic returns, idiosyncratic risk (nonsystematic risk), and beta (systematic risk). Service quality was derived from the airline quality rating, and three dependent variables were calculated by the Fama–French four-factor model. The data includes 1,512 monthly records from 1997 to 2006, across 21 airlines. Multiple regression and vector autoregressive models were applied to test relationships among all, low-cost, and non-low-cost airlines. The study found that service quality has a positive impact on idiosyncratic returns in non-low-cost airlines; non-low-cost airlines are less affected by changes in the external environment.  相似文献   
997.
We investigate when organizational justice matters to employees’ commitment in the postacquisition process after a company is taken over in a cross‐border acquisition. Overwhelming evidence from the literature suggests that employees who are treated fairly during acquisitions are more committed to their new firms. We extend this finding by dividing organizational justice into three subdimensions: informational justice, interpersonal justice, and procedural justice. We find evidence that procedural justice is an important antecedent of affective merger commitment at an early stage of the integration period, while informational justice becomes important at a later stage. Further analysis on heterogeneity between the target firm's employees and the bidder firm's employees reveals that, immediately after the acquisition, target firm's employees value knowing where they will be at the new firm (procedural justice), while bidder firm employees are more concerned about communication and transparency (informational justice). Our results point to the importance of organizational justice in a cross‐border merger and acquisition (M&A) setting and the need for a separate study of issues related to bidder firms and target firms. © 2016 Wiley Periodicals, Inc.  相似文献   
998.
In the literature on Olympic legacies and impacts, there is a dearth of materials that specifically address the issue of Olympic impact for non-hosting regions. The literature tends to deal with impacts at a national level, or at a hosting-city region level, neglecting in large part the degree to which benefits can be leveraged by non-hosting regions. A further limitation identified in the literature is a failure to engage in detailed formal evaluation of policy implementation where assertions of potential policy impact are based on untested assumptions. This study is intended to address both of these concerns. It presents an empirical, ‘bottom-up’ application of a Realist Evaluation framework to assess the impact of a policy initiative – Workplace Challenge – aimed at leveraging enhanced sports participation in a non-hosting region – Leicestershire – in the period leading up to the 2012 Games. In doing so, it seeks to identify which causal mechanisms worked within this particular context to produce the observed outcomes. The evaluation results demonstrate that the programme represented a positive approach to fostering regular engagement with sport and physical activities for some groups in some types of organisations, and that awareness and motivational factors associated with the London 2012 Games are, in this case, linked (albeit weakly) to an increase in sport and physical activity participation for specific groups taking part in the programme in particular organisational contexts.  相似文献   
999.
碳排放权市场价格发现功能的实证分析   总被引:2,自引:0,他引:2  
碳期货市场在碳市场扮演着极为重要的角色,通常具有价格发现的功能。本文分析了国际碳排放权交易市场两种主要商品EUA、CER的期货价格关系.通过向量误差修正模型和公共因子模型对欧盟碳期货EUA与CER期货进行了实证研究。结果显示:EUA、CER这两种主要碳排价格指标之间具有很高的相关性,存在长期均衡的协整关系,均扮演着重要的价格发现角色,同时EUA期货价格引导CER期货价格变化。  相似文献   
1000.
大数定律与小微企业授信模式研究   总被引:4,自引:0,他引:4  
贷款难一直是小微企业面临的最大问题。商业银行从自身盈利角度出发,面对日渐突出的金融脱媒现象,经营思路亟需转型,开发小微企业贷款业务以开辟新的业务增长点。本文基于大数定律,从商业银行角度出发,分析了小微企业授信模式。授信模式的选择和贷款利率确定是本文研究的两个重要方面,风险管拄贯穿整个授信过程。  相似文献   
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