黄河流域水资源空间利用结构的实证分析

以投入产出技术为基础,利用结构分解分析技术构建了水资源空间结构分解分析模型,并对黄河流域水资源利用和消费方式情况做了详实的结构分解分析,揭示了黄河流域水资源利用和消费的不合理结构,提出了合理利用水资源的有效措施.     

奇异值分解在重构模糊决策系统规则库中的应用

利用SVD技术重构PSG模糊规则库,降低规则的数量。根据矩阵奇异值的性质,适当取舍模糊规则库后件矩阵Ω的奇异值,得到Ω的近似表示Ω,利用Ω重新构建规则库,新规则库的输入变量域的维数比原规则库的维数小,从而有效地降低了模糊规则数。仿真结果证明了该方法是有效的。     

The L2 Rate of Convergence for Event History Regression with Time-dependent Covariates

Consider repeated events of multiple kinds that occur according to a right-continuous semi-Markov process whose transition rates are influenced by one or more time-dependent covariates. The logarithms of the intensities of the transitions from one state to another are modelled as members of a linear function space, which may be finite- or infinite-dimensional. Maximum likelihood estimates are used, where the maximizations are taken over suitably chosen finite-dimensional approximating spaces. It is shown that the L ₂ rates of convergence of the maximum likelihood estimates are determined by the approximation power and dimension of the approximating spaces. The theory is applied to a functional ANOVA model, where the logarithms of the intensities are approximated by functions having the form of a specified sum of a constant term, main effects (functions of one variable), and interaction terms (functions of two or more variables). It is shown that the curse of dimensionality can be ameliorated if only main effects and low-order interactions are considered in functional ANOVA models.     

基于电商承诺送达机制的多目标低碳MDVRP优化研究

针对存在多配送站的电商物流配送问题,首先,考虑实际装载量对物流配送过程中车辆燃料消耗量的影响,建立燃料消耗量模型,并结合电商平台的承诺送达机制,构建配送延迟时间函数。随后,提出了以最小化物流成本和延迟收货时间的多目标多配送站车辆路径规划问题,建立该问题的混合整数规划模型。再次,采用基于分解的多目标遗传求解算法对问题进行求解。该算法采用矩阵编码的方式,设计了基于贪婪搜索策略的启发式初始化方法,考虑到贪婪搜索策略容易陷入局部最优的劣势,在算法迭代过程中,允许部分不可行解存在以扩大解空间的搜索范围,并进一步设计了遗传算法的交叉和变异算子。最后,以具体物流配送案例进行数值实验,实验结果表明所设计的算法对求解本文模型是有效的。     

付息可赎回可转换债券定价解析式：完全拆解法

本文利用美式二值买权和上敲出买权等奇异期权,在Black-Scholes期权模型假设框架下,依据风险中性定价原理,将付息可赎回可转换债券“完全拆解”为七种相对简单证券的组合,并且通过这些简单证券的定价解析式推导出其定价解析式。同时,还推导出转息有效价值的解析式。这不仅仅为认知其价值组成提供了一个全新视角,而且相对现有的各种数值定价法,该解析式大大提高了定价效率。     

工资收入差异的解释：基于分位数回归的经验研究

利用CHNS2006年的数据,通过分位数回归方法从教育回报率、性别和工作部门的差异三个方面对中国工资收入差异进行研究,得出与以往研究不同的结论。结果表明：教育回报率在工资收入分布上的变动趋势是不定的。在工资收入分布的两端,大专以上学历对工资收入差距的影响相对较大。对不同性别间工资收入差异的分解表明劳动力市场上存在明显的性别歧视,而对部门间工资差异的分解表明在整个工资分布区间,这种差异呈倒＂U＂型走势。     

Axiomatic Based Decomposition for Conceptual Product Design

This paper describes a structured methodology for decomposing the conceptual design problem in order to facilitate the design process and result in improved conceptual designs that better satisfy the original customer requirements. The axiomatic decomposition for conceptual design method combines Alexander's network partitioning formulation of the design problem with Suh's Independence Axiom. The axiomatic decomposition method uses a cross‐domain approach in a House of Quality context to estimate the interactions among the functional requirements that are derived from a qualitative assessment of customer requirements. These interactions are used in several objective functions that serve as criteria for decomposing the design network. A new network partitioning algorithm is effective in creating partitions that maximize the within‐partition interactions and minimize the between‐partition interactions with appropriate weightings. The viability, usability, and value of the axiomatic decomposition method were examined through analytic comparisons and qualitative assessments of its application. The new method was examined using students in engineering design capstone courses and it was found to be useable and did produce better product designs that met the customer requirements. The student‐based assessment revealed that the process would be more effective with individuals having design experience. In a subsequent assessment with practicing industrial designers, it was found that the new method did facilitate the development of better designs. An important observation was the need for limits on partition size (maximum of four functional requirements.) Another issue identified for future research was the need for a means to identify the appropriate starting partition for initiating the design.     

Statistical data integration using multilevel models to predict employee compensation

This article considers the case where two surveys collect data on a common variable, with one survey being much smaller than the other. The smaller survey collects data on an additional variable of interest, related to the common variable collected in the two surveys, and out-of-scope with respect to the larger survey. Estimation of the two related variables is of interest at domains defined at a granular level. We propose a multilevel model for integrating data from the two surveys, by reconciling survey estimates available for the common variable, accounting for the relationship between the two variables, and expanding estimation for the other variable, for all the domains of interest. The model is specified as a hierarchical Bayes model for domain-level survey data, and posterior distributions are constructed for the two variables of interest. A synthetic estimation approach is considered as an alternative to the hierarchical modelling approach. The methodology is applied to wage and benefits estimation using data from the National Compensation Survey and the Occupational Employment Statistics Survey, available from the Bureau of Labor Statistics, Department of Labor, United States.     

基于稀疏主成分的能源利用效率综合评价及影响因素分析

基于能源消耗水平、能源高效利用水平、污染排放水平和污染治理水平四大准则层构建了评价能源利用效率的指标体系,使用数据包络分析、稀疏主成分方法和熵值法得到了我国各省市自治区2008-2018年的能源利用效率综合评价结果。在此基础上通过构建省际动态面板模型研究了能源利用效率的影响因素,回归结果显示：经济开放性、人均GDP、第三产业占比对能源利用效率有显著的正影响,能源消费结构、政府环境规制对能源利用效率有显著的负影响。最后就如何提高能源利用效率提出了相应的政策建议。     

Economic recession and the nature and pace of social change in Japan

Previous research has found a link between economic development and post-materialist and libertarian values. This research examines social change in values in Japan from the mid-1970s to the beginning of the 21st century. Using Japanese survey data, we investigate the nature and pace of social change during the economic crisis of the early 1990s, as well as in the periods before and after the burst of the bubble economy. We find that social change stalled during the economic crisis and resumed again in the late 1990s, but at a much lower level than in the late 1980s. We argue that economic period effects are largely responsible for the slowdown in social change in values in Japan at the end of the 20th century.