基于熵权理想点的房地产投资环境评价

房地产投资环境是影响房地产投资成功与否的关键因素,因此投资商在选择投资地点之前,应该做好房地产投资环境的评价工作。本文在建立房地产投资环境指标体系基础上,应用熵权理想点法对房地产投资环境进行评价排序,实现了定性分析和定量分析的结合,实例证明了该方法的合理性和实用性。     

Sequential fault diagnosis strategy with imperfect tests considering life cycle cost

The problem of sequential fault diagnosis is to construct a diagnosis tree that can isolate the failure sources with minimal test cost. Pervious sequential fault diagnosis strategy generating algorithms only consider the execution cost at application stage, which may result in a solution with poor quality from the view of life cycle cost. Furthermore, due to the fact that uncertain information exists extensively in the real-world systems, the tests are always imperfect. In order to reduce the cost of fault diagnosis in the realistic systems, the sequential fault diagnosis problem with imperfect tests considering life cycle cost is presented and formulated in this work, which is an intractable NP-hard AND/OR decision tree construction problem. An algorithm based on AND/OR graph search is proposed to solve this problem. Heuristic search based on information theory is applied to generate the sub-tree in the algorithm. Some practical issues such as the method to improve the computational efficiency and the diagnosis strategy with multi-outcome tests are discussed. The algorithm is tested and compared with previous algorithms on the simulated systems with different scales and uncertainty. Application on a wheel momentum system of a spacecraft is studied in detail. Both the simulation and application results suggest that the cost of the diagnosis strategy can be reduced significantly by using the proposed algorithm, especially when the placement cost of the tests constitutes a large part of the total cost.     

基于全寿命周期成本方法的地表水源热泵系统分析

利用空调系统的全寿命周期成本(LCC)的构成以及数学计算模型对重庆某地表水源热泵工程的全寿命周期成本进行了计算。结果表明,系统设置不合理,地表水源热泵的LCC值并非是最低的,会高于其他空调系统;而合理的地表水源热泵方案才能够得到最低的LCC值。对实际测试的数据进行了分析,找到了影响地表水源热泵的LCC值的主要因素有负荷特征、取水能耗和取水水温等。最后指出了取得最低的LCC值应注意的问题.     

二次函数拟合产品寿命周期存贮模型的最优解

本文采用直接法论论了用二次函数近拟合需求率符合产品寿命周期变化规律存贮模型的整体最优解，同时给出了应用实例。     

基于熵权改进的TOPSIS法的教师教学质量评价

为了提升高等学校教学质量,针对高校教师结构及教学特点,基于教师综合能力构建了科学、有效、可操作的教师教学质量评价指标,运用熵权法确定客观权重,提出了以TOPSIS法为基础的教学质量评价方法,并建立了高等学校教师教学评价体系.结果表明,熵权改进的TOPSIS法能弥补指标体系受主观偏好影响过大的缺陷,较好地体现了评价的客观性、公正性和时效性,搭建的教师专业评价系统界面友好,易于推广,为实际操作提供了便捷的软件支撑.     

含局部支承弹性地基板弯曲问题的迭代解法

研究了任意载荷作用下含局部支承弹性地基板在典型边界条件下的弯曲问题。首先利用纳维解和卷积叠加方法给出了任意载荷作用下无局部支承弹性地基板在典型边界条件下的解析解，然后采用未知待定反力来处理局部支承的影响，这些未知反力可以采用迭代格式进行求解。在此基础上建立了一种求解含局部支承弹性地基板弯曲问题的迭代解法。最后给出了数值算例来说明本文方法的具体应用，所得结果和有限元方法结果吻合较好。     

含局部支承弹性地基板弯曲问题的迭代解法

研究了任意载荷作用下含局部支承弹性地基板在典型边界条件下的弯曲问题。首先利用纳维解和卷积叠加方法给出了任意载荷作用下无局部支承弹性地基板在典型边界条件下的解析解,然后采用未知待定反力来处理局部支承的影响,这些未知反力可以采用迭代格式进行求解。在此基础上建立了一种求解含局部支承弹性地基板弯曲问题的迭代解法。最后给出了数值算例来说明本文方法的具体应用,所得结果和有限元方法结果吻合较好。