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941.
旅游专业教学改革应处理好与外部环境的互动关系, 新时期高等教育所进行的市场化、产业化改革为旅游专业的教改工作提供了全新的发展思路。应树立市场观念、竞争观念和品牌观念,通过创立旅游专业特色,培养社会适用人才以及市场化的运作模式,促进旅游高等教育的良性发展。  相似文献   
942.
Overuse of nitrogen fertilizer represents a considerable environmental problem globally, but especially in China. Recently, a recent approach on an experimental scale based on the diffusion of the so-called Three-Control Technology (TCT) successfully alleviated the overuse of nitrogen fertilizer in southern China villages in the Guangdong Province, serving as a reference point for other rice-producing countries tackling similar challenges. Here, we assessed the correlation between rice yields and reduction in the use of nitrogen fertilizer following the introduction of TCT. Our study was based on the collection of primary data from 248 households randomly selected from four rice-growing areas of Guangdong Province, China. Our results show that TCT significantly improved the efficiency in the use of nitrogen. Crucially, participating farmers, including both full adopters and partial adopters, were found to fundamentally change their application practices of nitrogen fertilizer, resulting in major improvements in the local soil and water systems.  相似文献   
943.
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   
944.
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   
945.
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   
946.
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   
947.
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   
948.
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   
949.
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   
950.
论"海尔"的个性化营销   总被引:1,自引:0,他引:1  
随着个性化需求的日益突出,消费个性化时代已经到来。海尔集团顺应市场需求推行个性化营销,从而使“海尔”在激烈的市场竞争中不断地发展壮大。  相似文献   
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