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1.
孙英潮 《科技和产业》2021,21(2):238-242
基于严寒区京沈客专朝阳试验段路基基床的温度监测资料分析,研究不同厚度聚氨酯保温板对高速铁路路基混凝土基床温度变化特性影响.测试结果表明:①铺设聚氨酯保温板能够有效阻断严寒区环境与路基基床间的热量传递,保温效果与板厚相关;②地温大多数时间呈阳高阴低现象,同时阴、阳坡路基温差波动幅度随埋深逐渐减小;③基床表层阴、阳面各测点的温度变化起始时间一致,而阴面的冻结时间比阳面晚一个月.由此表明,保温板能够有效降低环境与混凝土道床之间的热交换,但是对路基阴、阳坡的影响存在差异.建议在严寒地区高速铁路路基阳、阴坡可以采取不同厚度的聚氨酯保温板,减小阴阳坡地温差异,保持季冻土路基温度变化稳定.  相似文献   
2.
刘传义 《基建优化》2005,26(2):8-10
本文的目的在于介绍予应力混凝土构件设计采用“索梁分栽法”计算理论根据上的正确性。  相似文献   
3.
商务楼层作为一种特定的楼层,在世界各地兴起和迅速发展。通过阐述商务楼层的意义、起源与发展,揭示商务楼层与其他楼层的不同之处,目的是促使商务楼层进一步完善发展。  相似文献   
4.
Using data from the Frankfurt Stock Exchange we analyze priceformation and liquidity in a non-anonymous environment withsimilarities to the floor of the NYSE. Our main hypothesis isthat the non-anonymity allows the specialist to assess the probabilitythat a trader trades on the basis of private information. Heuses this knowledge to price discriminate. This can be achievedby quoting a large spread and granting price improvement totraders deemed uninformed. Consistent with our hypothesis wefind that price improvement reflects lower adverse selectioncosts but does not lead to a reduction in the specialist's profit.Further, the quote adjustment following transactions at thequoted bid or ask price is more pronounced than the quote adjustmentafter transactions at prices inside the spread. Our resultsindicate that anonymity comes at the cost of higher adverseselection risk. JEL Classification: G10.  相似文献   
5.
Using data from the Frankfurt Stock Exchange we analyze price formationand liquidity in a non-anonymous environment with similarities to thefloor of the NYSE. Our main hypothesis is that the non-anonymity allows the specialist to assess the probability that atrader trades on the basis of private information. He uses this knowledgeto price discriminate. This can be achieved by quoting a large spread and granting price improvement to traders deemed uninformed.Consistent with our hypothesis we find that price improvement reflects loweradverse selection costs but does not lead to a reduction in the specialist's profit. Further, the quote adjustmentfollowing transactions at the quoted bid or ask price is more pronounced than the quote adjustment aftertransactions at prices inside the spread. Our results indicate that anonymity comes at the cost ofhigher adverse selection risk.  相似文献   
6.
水泥混凝土路面是目前我国一种主要的高等级路面。但因为原材料、混凝土配合比、施工等因素的影响,水泥混凝土路面早期易产生裂缝。文章深入分析了水泥混凝土路面出现早期裂缝的主要原因,提出了防治早期裂缝的对策。  相似文献   
7.
文章对某工业厂房现浇楼板产生裂缝进行调查,分析了裂缝的特征和产生的原因,介绍了防治裂缝的措施以及修补裂缝的方法。  相似文献   
8.
李林 《基建优化》2002,23(4):18-19
为了培养一支年轻的项目经理队伍,推动我国建设事业,必须用对立统一的观点认识年轻项目经理,用具体问题具体分析的方法对待年轻项目经理,在实践中选拔培养年轻项目经理。  相似文献   
9.
Abstract:  This study finds evidence of significant long-term underperformance following rights issues made during 1986-95 in the UK. The findings are resilient to a number of methodological controls. In contrast, our results for a smaller sample of open offers made during 1991-95 show strong positive performance over a 5-year post-issue period, implying that firms making open offers had better growth prospects than firms making rights issues. During 1986-90, a period when open offers were rarely used, firms appeared to be making rights issues to exploit overvaluation. However, this was not evident for rights issues made during 1991-95, a period when open offers were more commonly used.  相似文献   
10.
This paper compares different methods used for stock repurchase and examines the role of signaling in the U.S. and China's capital markets. We find that the ways to buyback stocks are very different in the two countries. Most U.S. stocks are repurchased through open market and the signals sent to the market through open market repurchase are getting weaker. Even though stock repurchases are at their early stage in the Chinese stock market and the dominated way to buyback is through a negotiated repurchase agreement for non-floating shares, the power of signaling seems much stronger. Examining stock prices pre- and post-repurchase, we find that stock repurchase records an average abnormal return of 3.42% on the announcement date and 3.24% on the date of actual renurchase.  相似文献   
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