坩埚热导率对晶体生长温度场的影响

本文通过有限元数值方法计算了坩埚热导率对晶体生长温度场的影响,指出当坩埚热导率大于晶体材料的热导率时,生长区域的纵向温梯会有大幅度减小,反之,温梯变化较小。并且认为当坩埚侧面与环境的热交换系数很大时,坩埚热导率的影响作用变小。并指出坩埚热导率可以通过热处理及其他手段予以调节。     

完全经济效益的研究——兼论提高经济效益的途径

在文献[1]的基础上提出了完全经济效益系数的概念,建立了计算公式,分析了影响完全经济效益系数的因素,讨论了提高完全经济效益的一些途径,建立了完全经济效益系数变动的基本方程,讨论了生产要素系数变动的影响力。     

互连网络拓扑优化设计

论述了互连网络拓扑优化设计问题,建立了必要的数学模型,该数学模型是一个非线性组合优化问题,它属于NP—完备类问题。采取拉格朗日松弛法、次梯度迭代算法和启发式算法,得出最优下确界和结论。     

具体应用中的矛盾分析法之种种

矛盾分析法在科学认识中的具体应用,可作多侧面的展开,形成多方面的更为具体的科学方法。这些具体科学方法可概括为,矛盾的定性分析法、矛盾的定位分析法、矛盾的定点分析法、矛盾的定量分析法、矛盾的定势分析法、矛盾的历史过程分析法、矛盾的逻辑过程分析法、矛盾的系统分析法、矛盾的对立面互补分析法等等.它们均体现哲学方法与具体科学方法的一致性。     

论统计理论研究方法体系

一、统计理论研究方法体系的提出　　在相当长的一段时间里,我国统计界在进行统计理论研究时虽有意无意地采用了一些研究方法,但是,这些研究方法基本上分散零乱的,没使之系统化,这也许是造成我国统计理论研究还比较落后的一个重要原因。随着市场经济的不断完善,统计理论研究的不断深入,人们发现我国统计理论研究在向新领域、新高度跨越时,现有的方法难以适应研究的需要,客观实际方面要求我们应不断地总结过去的研究方法,创建新的研究方法。因此,对统计理论研究方法本身的研究被提到议事日程。实际上,当今科学技术的飞跃进步,科…     

Moment‐Independent Sensitivity Analysis Using Copula

In risk assessment, the moment‐independent sensitivity analysis (SA) technique for reducing the model uncertainty has attracted a great deal of attention from analysts and practitioners. It aims at measuring the relative importance of an individual input, or a set of inputs, in determining the uncertainty of model output by looking at the entire distribution range of model output. In this article, along the lines of Plischke et al., we point out that the original moment‐independent SA index (also called delta index) can also be interpreted as the dependence measure between model output and input variables, and introduce another moment‐independent SA index (called extended delta index) based on copula. Then, nonparametric methods for estimating the delta and extended delta indices are proposed. Both methods need only a set of samples to compute all the indices; thus, they conquer the problem of the “curse of dimensionality.” At last, an analytical test example, a risk assessment model, and the levelE model are employed for comparing the delta and the extended delta indices and testing the two calculation methods. Results show that the delta and the extended delta indices produce the same importance ranking in these three test examples. It is also shown that these two proposed calculation methods dramatically reduce the computational burden.     

关于三分Cantor集的结构的一些新结论

旨在采用代数的方法来研究三分Cantor集的结构特点。主要结果除了给出三分Cantor集的代数构造外还定义了仿四进位；结合代数构造、拓扑构造以及仿四进位分别给出并证明了三分Cantor集及其余集的结构公式，从而改进了已有的结论。     

李土司先世辨正

本文主要对土族李土司家谱中关于其先世为李晋王的传说加以考证,认为李土司家族传说的晋王即是曾五次出征河湟的西夏晋王察哥,李土司初祖赏哥为晋王察哥子孙,所任之职为西夏齐王遵顼大都督府,出镇鄯州,夏封鄯善王,后世遂误传为元代之事。     

Distribution of the two‐sample t‐test statistic following blinded sample size re‐estimation

We consider the blinded sample size re‐estimation based on the simple one‐sample variance estimator at an interim analysis. We characterize the exact distribution of the standard two‐sample t‐test statistic at the final analysis. We describe a simulation algorithm for the evaluation of the probability of rejecting the null hypothesis at given treatment effect. We compare the blinded sample size re‐estimation method with two unblinded methods with respect to the empirical type I error, the empirical power, and the empirical distribution of the standard deviation estimator and final sample size. We characterize the type I error inflation across the range of standardized non‐inferiority margin for non‐inferiority trials, and derive the adjusted significance level to ensure type I error control for given sample size of the internal pilot study. We show that the adjusted significance level increases as the sample size of the internal pilot study increases. Copyright © 2016 John Wiley & Sons, Ltd.     

天津城市风貌塑造中的非物质要素传承

天津建卫六百年以来．社会文化的演变经历了数个重要过程．每个过程对天津城市风貌的塑造都起到了不同的作用。纵观这六百多年的城市建设历史不难发现．天津城市文化及核心价值观体现在如下几方面：