粘贴技术在桥梁加固工程中的应用

本文根据实例介绍采用环氧混凝土粘贴钢筋加固桥梁的主梁下缘和采用建筑结构胶粘贴钢板加固桥梁的横梁及桥面板的实施方案和粘贴工艺。该法操作方便，质量可靠，不仅适用于桥梁加固工程．还可用于其它市政、工矿企业厂房等设施的维修。     

关于我国海底隧道建设若干工程技术问题的思考

结合国内外海底及水下隧道建设的实例,从海底隧道的工程准备、技术方法、方案比选、风险管理、工程理念等方面进行论述。提出海底隧道项目应从长计议、及早打算、周密安排,才能少走弯路,不失时机;对沉埋法、暗挖法、盾构法修筑海底隧道的优缺点进行分析,提出采用建议及应当注意和研究的问题;从线位和线形、线数和断面、附属及运营设施、建造方式等方面对海底隧道工程方案进行比选,提出建议;提出我国海底隧道采用风险管理的建议;进一步强调要树立正确的工程建设理念。     

Transit technology investment and selection under urban population volatility: A real option perspective

This paper addresses transit technology investment issues under urban population volatility using a real option approach. Two important problems are investigated: which transit technology should be selected and when should it be introduced. A real option model is proposed to incorporate explicitly the effects of transit technology investment on urban spatial structure in terms of households’ residential location choices and housing market. The trigger population thresholds for investing in a transit technology project and for shifting from a transit technology to another are explored analytically. Comparative static analyses of the urban system and transit technology investment are also carried out. It was found that (i) transit technology investment can induce urban sprawl; (ii) ignoring the effects of transit technology investment on urban spatial equilibrium can lead to a late investment; and (iii) there is a significant difference in the trigger population thresholds for transit technology shift estimated by the net present value approach and the real option approach.     

Network-based real option models

Building on earlier work to incorporate real option methodologies into network modeling, two models are proposed. The first is the network option design problem, which maximizes the expanded net present value of a network investment as a function of network design variables with the option to defer the committed design investment. The problem is shown to be a generalized version of the network design problem and the multi-period network design problem. A heuristic based on radial basis functions is used to solve the problem for continuous link expansion with congestion effects. The second model is a link investment deferral option set, which decomposes the network investment deferral option into individual, interacting link or project investments. This model is a project selection problem under uncertainty, where each link or project can be deferred such that the expanded net present value is maximized. The option is defined in such a way that a lower bound can be solved using an exact method based on multi-option least squares Monte Carlo simulation. Numerical tests are conducted with the classical Sioux Falls network and compared to earlier published results.     

水运建设项目经济评价净现值法的缺陷及对策

从净现值法的基本假设出发，首先分析净现值法在水运建设项目经济评价中存在的问题，指出用净现值法无法预估项目的不确定性价值。然后提出引入实物期权对净现值法进行修正的基本方法，为水运建设项目的投资决策提供了一个崭新的决策思路。     

一个基于B-S期权定价理论的人力资本定价模型

基于现有应用B-S期权定价理论的人力资本定价模型的不足,本文考虑人力资本投入率因素,并在计算定性变量时综合运用模糊数学与精确数学的方法。在此基础上本文构造了一个人力资本定价模型,试图对现有应用了B-S期权定价理论的人力资本定价的思路作出部分改进。     

网络技术在道路施工管理中的应用

结合道路工程施工管理中的体会和施工组织方案优化过程分析 ,介绍在道路施工管理中如何运用网络技术     

上海东海大桥桩基础防腐蚀方案比选

上海东海大桥工程全长32.5km,是国内第一座特大型跨外海桥梁。大桥设计使用寿命100a。大桥桩基础采用PHC管桩、钢管桩、钻孔灌注桩三种形式,为了达到受海洋环境的腐蚀下的设计使用寿命,减少后期维修费用,对各种桩型分别进行防腐蚀方案的论述与比选,以确定较合适的防腐蚀措施。     

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船舶作为航运企业最重要的生产资料,其前期的投资决策分析至关重要.一直以来,船舶投资风险价值的计算是困扰人们的问题之一,实物期权理论与B-S定价模型的发展为其提供了一个解决办法.但B-S定价模型中最重要的假设条件是资产价格波动符合正态分布,这与现实差距较大.本文以分形分布条件代替B-S定价模型中正态分布的假设,建立起分形期权定价模型,并利用BDI价格指数进行实证分析.结果证明BDI对数收益率序列的H指数大于0.5,说明BDI收益具有较强记忆性,呈现尖峰胖尾特征.在此条件下,以传统B-S定价模型计算出的船舶投资实物期权价值大于分形期权价值,说明其高估了船舶投资的管理柔性价值,这会使投资者产生盲目乐观心理,进而增大投资决策风险.     

某排水工程施工方案优选中的价值工程应用

本文首先简要阐述了价值工程的基本工作原理 ,其次从工程实践出发 ,应用价值工程对某排水工程施工方案进行优选 ,合理降低造价、缩短工期。