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71.
为了提高电力系统的经济性与安全性,评估接入分布式发电(DG)后电网企业的综合效益成为指导企业决策的主要依据,为日后电网整体规划挑选最优方案提供理论依据。在研究含分布式发电的配电网的综合效益的基础上,从DG接入对系统网损、扩容投资、售电损失、生态环境等综合社会效益方面产生影响出发,分析各个部分相应模型,完善整体综合效益量化模型。以电网企业的整体效益最大化为目标,考虑经济性约束条件,保证DG的合理运行。由算例分析可知,电网企业整体社会收益增加,可实现经济接入并带来利润。既验证了模型的合理性,又为电网企业应季规划电力分配的决策提供数据支持与依据。  相似文献   
72.
通过对新疆油田市场化钻井队伍监督管理现状的分析,查找原因,采取以井控安全为中心,突出重点工序、关键环节的监督检查,探索出适合新疆油田市场化钻井队伍的监督管理方式。通过推广应用,充分发挥了工程监督的作用,促进了市场化钻井队伍的良性发展。  相似文献   
73.
为了提高潮汐交通道路的安全度,基于南京市虎踞路调查的交通数据,分析其潮汐交通特性,针对潮汐路段提出优化设计方案,在可变车道内,分析车辆的速度、道路宽度以及汽车转弯半径对分流带长度的影响,利用切函数与约束函数,设计一定长度的自动可移动式分流带。利用交通微观仿真平台vissim对实施协调控制后的结果进行仿真实验,结果表明控制后的车头间距增大,通行效率得到提高,安全度提高。  相似文献   
74.
Net neutrality rules have been implemented in many developed countries, often in response to concerns over network operator market power and potential blocking or throttling of content. However, developing countries typically have significantly lower levels of internet penetration and usage. Market power in respect of internet access looks quite different given that mobile is the predominant means of connection and there are often three or more mobile operators. In South Africa, there is a quasi-monopoly in the paid satellite broadcasting market and broadband providers zero-rating content from third parties (such as Netflix) may bring about more competition. We test the main theories of harm arising in the net neutrality debate, including network operator market power and exclusion among content providers using data on the number of announced prefixes and peers and IP addresses and considering examples of bundling and zero-rating conduct by operators. We find that net neutrality rules are less likely to be required in South Africa and other developing countries and that strict enforcement of such rules could in fact hinder competition in markets for content, telecommunications networks and other related markets.  相似文献   
75.
Many food regulations focus on test/measurement indicators, such as hazard analysis and critical control points (HACCP) and traceability, etc. Other than these indicators, the food industry uses various cues such as product origin as indicators of product quality. However, in an environment where consumers’ confidence in food safety is low due to frequent food safety scandals, little is known about the efficiency of these test/measurement indicators and cues. This paper used the primary data collected in Zhengzhou (China) to estimate consumers’ preferences for test/measurement indicators and a new cue of “own farm” for milk powder. Our results show that country of origin is the most important cue attribute, followed by price and own farm. The importance of test/measurement indicators such as organic, traceability, and HACCP certification is relatively low. Also, the individual parameter estimates show that consumers’ preferences for test/measurement indicators currently in the market are weak and fragile. Interestingly, price has an inverse-U-shaped relationship with consumer utility, implying that Chinese consumers may perceive low-price milk powder as low quality. The results of this study provide important insight for regulatory authorities and the food industry to develop more effective policies and programs to improve consumer preferences for milk powder.  相似文献   
76.
针对国内外储罐事故的经验教训,系统梳理了国内外储罐设计标准。为了提高国内储罐标准的先进性,分别从储罐附件设计、储罐消防设计和储罐安全设计3个方面,深入研究了国内外标准差异。国外储罐标准技术先进性包括储罐安全距离、浮顶储罐浮盘状态监视、储罐泄漏检测和防渗设计等方面。最后借鉴国外标准先进理念,就完善国内储罐设计标准提出了建议。  相似文献   
77.
分析了通信专网企业在安全管理方面存在的主要问题,结合企业自身安全管理的重要举措及所取得的成效,探讨了服务于煤炭企业的通信专网企业安全管理的发展之路。  相似文献   
78.
This article draws on fieldwork conducted in the back‐office of a major retail UK bank and explores how, when introducing change, management drew on contradictory normative and rational discourses. Its primary concern is to explore how, in this context, employees engaged in contradictory acts that combined elements of both resistance (‘making out’) and consent (‘making do’) that are difficult to disentangle. It is argued that although both are moves within the game, they can be distinguished from each other because the former works against the grain of corporate intentions, whereas the latter works with them.  相似文献   
79.
This study analyzed the interaction between message frames and recipients’ prior knowledge. The hypothesis is that less prior consumer knowledge will result in a larger framing effect. That is, if the subjective knowledge of the public is low, then the controversy created by mass media regarding a specific food-related event will be larger. Empirical results show that message frame has an influence on college students’ purchasing intentions. College students showed distinct responses in purchasing intention based on different headlines and different amounts of information within articles. The results further suggest that the framing effect depends not only on message frames, but also on the prior knowledge of the message recipient. Those who have less knowledge have larger variation in their purchase intention when responding to different message frames. This suggests that people with less knowledge are more likely to panic due to mass media reports regarding a food hazard issue. More informed consumers have less dramatic responses to food safety issues compared to less informed people.  相似文献   
80.
E. coli O157:H7 is an important source of foodborne disease. The E. coli pathogen occurs naturally within the rumen of livestock (including cattle) and does not affect the health of the cattle, however, can be a source of cross-contamination during food processing or environmental contamination of drinking and irrigation water supplies. A vaccine to reduce the risk of cattle shedding E. coli is licensed for use in Canada and the US, however, adoption of the vaccine by cattle producers has been extremely low. Using data from a survey of cow–calf producers in western Canada, the influence of a set of thirteen incentives to encourage adoption of the vaccine is examined using Best–Worst Scaling. Incentives include policy interventions, market/supply chain incentives, production protocol incentives, and producer reputation incentives. Heterogeneity in producer responses to the incentives is evident and is further explored with a Latent Class Cluster analysis. Results suggest that a ‘one size fits all’ policy to encourage adoption of an E. coli vaccine by cattle producers may be challenging.  相似文献   
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