空气锤能量计算理论的研究与实践

本文概括了作者近年来对空气锤打击能量计算理论的研究。并通过了国内外检测的验证。着重阐述理论研究用于实践后对传统结构设计的改革,部分设计改革已在工厂实施,经受了生产实践的考验。     

基于BP神经网络的建筑工程投标价格是否低于成本的评判

将BP神经网络理论应用于建筑工程评标中投标价格是否低于成本的评判，分析了建筑工程成本的构成及影响因素，讨论了评判网络结构的设计，学习算法等问题。     

无标底招标实施的风险及对策研究

无标底招标是我国建筑市场发展的必然趋势，也是加入WTO后我国建设工程交易的主要方式。文章分析了无标底招标的内涵，并通过对无标底招标实施的风险的剖析，提出了应对风险的对策和建议。     

17-4PH马氏体沉淀硬化不锈钢锻造开裂问题的解决措施

17-4PH马氏体沉淀硬化不锈钢材料的用途越来越广,不过其产品在锻造过程中表层开裂特别严重。钢锭是通过电渣重熔冶炼出来的,无重熔时暂留缺陷。钢锭通过机床加工两端和车光外径,在鐓粗过程、拔长过程、压下过程都会产生严重开裂事故,导致生产不能正常进行。为了解决这种情况,在本文的分析研究中,对其原因进行深入分析,并提出相关解决措施。     

基于组合赋权与TOPSIS法的政府工程采购评标研究

考虑到政府工程采购评标是一个有限方案的多目标多层次决策问题,提出组合赋权与TOPSIS(逼近理想解排序)法。首先,构建了政府工程采购评价指标体系;然后,针对现有政府工程采购评标方法的不足,提出AHP(层次分析法)组合熵法确定各评价指标的组合权重,再结合TOPSIS法对政府工程采购各方案进行评标;最后,以某政府工程采购评标为实例,验证了组合赋权与TOPSIS法在政府工程采购评标中的应用是可行的。     

价值工程在核电建设过程中的应用初探

核电站建设时间长,过程复杂,接口众多,专业涉及面广,价值工程的应用前景十分广阔。文章基于核电建设工程实践,着重探讨了价值工程在方案比选、招评标及方案优化等方面的运用。     

市民收入不均与城市住宅价格空间分布——理论模型与数值模拟

文章通过对市民收入分布特征和市民购房能力与意愿的假设,将市民收入和住宅价格结合起来,从理论上探讨了市民收入不均对城市住宅价格空间分布的影响,并进行了数值模拟。分析表明,商业聚集导致城市从中心到外围房价呈逐渐下降的外在空间规律,是由市民收入差异及其购房竞价这个"内因"实现的。收入不均程度的变化会引起城市不同区位的房价变化,市民总收入一定时,基尼系数增大会导致城市中心房价上升和边缘房价下跌;高基尼系数下出现多次购房的可能较大,这将抬高相关区位的房价。     

Post‐Earnings Announcement Drift: Bounds on Profitability for the Marginal Investor

The persistence of the post‐earnings announcement drift (PEAD) leads many to believe that trading barriers prevent investors from eliminating it. We examine two factors that have not been adequately addressed by the literature: the exact timing of earnings announcements and liquidity costs. Under a wide range of timing and cost assumptions, our results leave little doubt that over our sample period the PEAD was highly profitable after trading costs. An additional incremental investor could have earned hedged‐portfolio returns of at least 14% per year after trading costs. Over our sample period, investors did indeed leave money on the table.     

The Determinants of Outcome in UK Take–over Bids

In this paper we have investigated the determinants of the outcome of 238 friendly and hostile take–over bids that occurred in the UK during the 1980s. We also use our model for prediction purposes and in order to map the effects of a variety of independent variables on the probability of the bid being successful. Our main results can be summarised as follows. First, target management resistance and the wealth effect of a bid are key determinants of the outcome of a bid. Second, we find limited evidence to suggest that share ownership by the bidding company and by target directors also contributes significantly to bid outcome. In the latter case we find a non–linear relationship consistent with the argument that when director holdings are low the bid is discouraged but when they are high the bid is encouraged. Third, our model is good at predicting outcome for all bids but weak at predicting the outcome of hostile bids on their own.     

Equilibrium uniqueness with perfect complements

The present note analyzes the simultaneous ascending-bid auction with arbitrarily many asymmetric bidders with decreasing marginal valuations under complete information. We show that the game is solvable by iterated elimination of weakly dominated strategies if the efficient allocation assigns at least one unit to every player and if bid increments are sufficiently small. In that unique equilibrium, bidders immediately reduce their demand to the efficient allocation, and the auction ends in the first round of bidding.We would like to thank seminar participants at UC Davis, in particular Klaus Nehring and Louis Makowski for comments. Financial support by the Alexander–von–Humboldt Foundation through a Feodor–Lynen grant and by the Deutsche Forschungsgemeinschaft, SFB Transregio 15, “Governance and Efficiency of Economic Systems” is gratefully acknowledged.