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891.
This article investigates the short‐term relationship between media coverage, stock prices, and trading volumes of eight listed German companies. A content analysis of news reports about the selected companies and a secondary analysis of the daily changes in closing prices and the trading volumes of these companies were combined in a time‐series design. After ARIMA‐modeling each of them, the results suggest that media coverage rather reflects than shapes the development at stock exchanges from a short‐term perspective (2 months). There were almost no hints for a widespread media effect, that is, an impact on so many investors that it will result in a measurable change in stock prices or trading volumes. Finally, theoretical and methodological consequences for exploring widespread media effects are discussed. 相似文献
892.
893.
In the last 15 years, glass fiber hoop reinforced composite systems emerged as an acceptable, successful method for repairing corroded and mechanically-damaged onshore pipelines where the primary load is internal pressure. The feasibility of extending these repairs to offshore pipes such as risers require a thorough understanding of the complex combined load profiles; overlay of significant tension, bending, internal and external pressure. Herein an innovative design based on integrated computational models and full-scale tests is presented to address the viability of reinstating capacity to offshore pipelines and risers. The experimental program was based on a collaborative test matrix developed with the participation of composite repair manufacturers. The outcome guided and led to an easily deployable carbon–fiber composite repair system which was based on limit analysis methods and strain-based design techniques. It is anticipated that the results of this program will foster future investigations by integrating operator’s insight and in situ data gathering to extend composite repair for offshore needs. 相似文献
894.
正确选择煤粉,其性能要求同时具有低灰分、高挥发分和高膨胀指数,以及具有合适的筛分粒度这一关键因素,以确保所生产的铸件没有机械粘砂缺陷和表面质量问题.通过仔细选择、安全操作和加工处理,煤粉仍然是一个优良的、简易的、经济的有效解决方案.煤粉在储存、加工和运输过程中易于调节,然后经过进一步的安全处理,最终被铸造厂使用.尽管煤粉有诸多不足之处,对于最终用户来说,它仍然是经济合算的.而且现代加工和筛分方法确保它在最佳条件下使用. 相似文献
895.
Ernest R. Alexander Ph.D. AICP 《Journal of the American Planning Association. American Planning Association》2013,79(1):91-92
Progressive planners—those who are involved in radical reform—confront dilemmas in their work that do not apply to traditional social reformers. Because they seek to transform society into something other than what it is, progressive planners must evolve new responses to everyday problems. At the same time, they must change commonly held perceptions of how society defines those problems. Finally, they cannot avoid working with traditional political and economic organizations. The ability of progressive planners to perceive and confront those dilemmas can affect the success of their initiatives. 相似文献
896.
897.
Cara Cocking Stephan Helling Marcus Oswald Peter Rammelsberg Gerhard Reinelt Alexander J. Hassel 《Color research and application》2010,35(3):233-239
A key criterion in the design of dental shade guides used for matching tooth color is that the shade tabs cover the natural tooth color space as completely as possible with a manageable number of tabs. Earlier studies have designed hypothetical shade guides from a given population of tooth colors described in the CIELAB system using the goal of minimizing the mean coverage error. In this study, we investigate this topic using the goal of maximizing coverage, meaning that as many measured colors as possible were within a given color difference from the nearest shade tab of the guide. We use techniques of linear discrete optimization to determine the positions of the shade tabs and consider both color difference formulas, CIELAB and CIEDE2000, in an exemplary tooth color population. We obtain coverage error and coverage figures for hypothetical shade guides of various numbers of tabs designed with the goal of either minimizing coverage error or maximizing coverage. Results show that discrete optimization and the goal of maximizing coverage could be used to improve shade guide development. The described technique could be used not only for dental shade guides development, but also for any purpose requiring coverage of as many colors as possible while keeping the number of reference colors manageable. © 2009 Wiley Periodicals, Inc. Col Res Appl, 2010 相似文献
898.
Large parabolic dish concentrators have been widely employed in solar thermal applications. The supporting structure of a solar dish concentrator consists of a circular frame, a central post, and front and rear cables connecting the frame to the post. The tensions in the cables cause compressive stresses in the circular frame and the central post, and this support structure must be designed for stability. In this paper, the nonlinear buckling behavior of the supporting structure of a cable-stayed circular frame is studied in detail. A three-dimensional finite element model of the supporting structure is developed to predict the critical cable tensions that would cause buckling of the circular frame and to determine the associated buckling mode shapes of the supporting structural system. The results show that the buckling load of a cable-stayed circular frame depends not only upon the cross-section of the frame, but also upon the number of cables and the inclinations of the cables. In all cases, in-plane buckling modes are predominant. The concentrated torques resulting from unbalanced cable tensions tend to induce the out-of-plane buckling modes. 相似文献
899.
Photocatalytic hydrogen production from water solutions of dimethyl methylphosphonate (DMMP), trimethyl phosphate (TMP), triethyl phosphate (TEP), and radiation protective amine WR 2721, that imitate nerve chemical warfare agents was studied for the first time. Platinized titianium dioxide Degussa P25 was used as catalyst. No significant hydrogen evolution was detected without organic electron donors – sacrificial agents. 相似文献
900.
As the economy becomes global and ICT-reliant, approaches practiced in enterprise software product development and enterprise resource planning (ERP) system implementation must cope with increasingly complex situations induced by contemporary supply chain and regulations. Compliance with regulations in the market is one aspect of the requirements that enterprise software must meet. Recent research of KPMG IT Advisory has confirmed that where little attention is being paid to the value-added tax (VAT) issues during large ERP projects, there is a higher VAT-risk exposure. In a design-oriented approach, we first identify the stakeholders and their interests in the VAT compliance of ERP systems. Enterprise architecture (EA) and model driven engineering in a multi-level perspective serve as the source of solution patterns. The efficient solution of compliance problems builds upon stakeholders utilizing a set of interdependent models and methods that are suitably allocated to the public and proprietary domains. 相似文献