基于PLC的路灯控制系统设计

基于PLC控制的路灯控制系统在灯具节能上把握了节能的新方向,采用节流降功率,克服了隔灯点亮的光照不均匀性和降压节能的灯具寿命缩短、不能点亮等问题。该系统具有运行可靠、可操作行强、可连续扩展、节能效果明显、成本和维护费用低等优点,可通过编程来改变控制方案,适用于有不同时差的地区,是路灯节能的发展趋势。     

内燃机代用燃料的废气排放探讨

机动车尾气污染已更甚于煤烟型污染 ,成为城市大气环境的主要污染源 ,分析了燃用 7种不同的代用燃料的 CO,NOx,HC,CO2 的排放量及烟度值 ,并与燃用传统燃料(汽油或柴油 )作了比较 ,其中着重分析了燃用压缩天然气及压缩天然气 -柴油双燃料的废气排放情况 ,指出燃用代用燃料将减轻对大气环境的危害 ,改善大气环境质量。     

“声音”与“眼光”的结合与分离——谈《牧师的黑面纱》中的叙事视角

本文从结构主义叙事学关于叙事视角的理论出发,分析了霍桑的短篇小说《牧师的黑面纱》中出现的叙事声音和叙事眼光的结合与分离。在该故事中出现的叙事声音或与叙事眼光相结合,为读者提供背景信息,做出评论,或与叙事眼光部分结合,制造悬念,引人入胜,或与叙事眼光相分离,从故事中人物的角度向读者交代信息,凸现反差,深化主题。     

人民币升值不宜激进——对人民币汇率的认识及政策建议

文章认为:尽管人民币升值趋势已经形成,也很难逆转,但对汇率政策我们应该有更加客观的分析,不能把解决矛盾的重任统统压在某一项政策特别是汇率政策上,目前情况下,人民币升值不宜"疾风暴雨",采取"润物细无声"式的稳步升值也许更为合适。     

控制权转让、产权性质与公司绩效

本文以2003—2011年A股发生终极控制人变动的上市公司为样本,考察了四类控制权变动对公司绩效的影响。结果发现:(1)国有转民营和民营转国有都能显著提高公司绩效,而国有转国有和民营转民营对公司绩效的提高并不显著;(2)民营转国有对公司绩效的提高源于隧道效应的减弱,而国有转民营对公司绩效的提高则是隧道效应的减弱和经理人代理问题的降低两方面共同作用的结果。以上结论说明,产权性质的改变在控制权转让过程中起到了积极的作用,不同所有制结构在治理问题上各有优缺点:国有企业往往面临更为严重的经理人代理问题,而民营企业的大股东隧道效应更为严重。所有权性质的转变导致治理形式的转换,新的治理形式克服了原先治理形式的缺点,从而提高了效率。本文结论有利于缓解"国进民退"的争论,同时为进一步推进混合所有制改革提供了经验证据。     

依托“校企合作”探索商务英语人才培养新思路

在“一带一路”战略背景下,区域外向型企业迎来了前所未有的重大历史发展机遇,对国际化复合型商务英语人才提出了更高的要求.商务英语专业人才培养与地方外向型经济发展可形成优势互补,良性互动,成为驱动区域经济转型升级的重要着力点.高校商务英语专业应以校企合作为切入点,充分利用校企双方的互补优势,打造双师型师资队伍,构建特色课程模块,创建开放性、系统性和综合性的人才培养平台,为区域经济发展输送急需的高级国际化人才.     

Consumer Preference for Meat in China: A Case Study of Beijing

We analyze Chinese consumer preferences for pork shoulder-cut attributes during the recent period of fluctuating food prices caused by production and market anomalies. Consumers were randomly sampled in Beijing, China. Results indicate that consumers place great importance on where they purchase pork products as well as on whether the animals are raised with organic feed. Whether pork is fresh or previously frozen does not appear to matter much to consumers. This may provide partial support for the Chinese government's policy of using frozen pork reserves to stabilize pork prices.     

Portfolio Distortions Among Institutional Investors: Evidence from China

The behavior of institutional investors often deviates from established personal or social norms; this deviation may reflect either an informational advantage or a psychological bias. In this paper, we investigate the reasons Chinese mutual funds hold lottery-type stocks, which are characterized by low average returns and high risk. We find that funds at the aggregate level do not exhibit a propensity to gamble, but when they do gamble, they earn abnormal returns on lottery-type investments. Gambling-related outperformance is greater among held firms with characteristics that enable fund managers to obtain more informational advantages. Our results suggest that portfolio distortion is driven by the ability of managers to capitalize private information rather than by behavioral bias.     

Does option trading convey stock price information?

After executing option orders, options market makers turn to the stock market to hedge away the underlying stock exposure. As a result, the stock exposure imbalance in option transactions translates into an imbalance in stock transactions. This paper decomposes the total stock order imbalance into an imbalance induced by option transactions and an imbalance independent of options. The analysis shows that the option-induced imbalance significantly predicts future stock returns in the cross section controlling for the past stock and options returns, but the imbalance independent of options has only a transitory price impact. Further investigation suggests that options order flow contains important information about the underlying stock value.