基于概率积分法的顶管施工地表变形预测

为了预测顶管地表变形,分析顶管施工地层损失的原因,将概率积分法应用于顶管地表变形预测,在VC6.0下开发了相应的计算程序,可以给出顶管地表沉降、倾斜、曲率、水平变形、水平移动5种变形,以及绘制顶管地表变形的横断面图、平面等值线图和三维立体图。将该程序应用于广州某顶管工程地表变形预测,与实测数据对比,验证了本文方法和程序的正确性,从而为顶管地表变形预测提供了一种新方法。     

Least squares fitting of an affine function and strength of association for interval-valued data

The ultimate goal of this paper is to determine a measure of the degree of dependence between two interval-valued random sets, when the dependence is intended in the sense of an affine function relating these random elements. For this purpose, a general study on the least squares fitting of an affine function for interval-valued data is first carried out, where the least squares method we will present considers that squared residuals are based on a generalized metric on the space of nonempty compact intervals, and output and input random mechanisms are modelled by means of convex compact random sets. For the general case of nondegenerate convex compact random sets, solutions are presented in an algorithmic way, and the few cases leading to nonunique solutions are characterized. On the basis of this regression study we later introduce and analyze a well-defined determination coefficient of two interval-valued random sets, which will allow us to quantify the strength of association between them, and an algorithm for the computation of the coefficient has been also designed. Finally, a real-life example illustrates the study developed in the paper.  The research in this paper has been partially supported by DGESIC Grants DGE-99-PB98-1534 and DGE-98-PB97-1282 of the Spanish MEC. Their financial support is gratefully acknowledged. Acknowledgements. The authors are deeply grateful to Professor Wolfgang N?ther from the University of Freiberg and their colleagues Professors Norberto Corral, Miguel López-Dı′az and Ignacio MartVnez for their valuable comments and suggestions in connection with this paper. The real-life data which illustrate the study in this paper have been supplied by Aurora Fonseca, Head of the Servicio de Nefrologı′a, and Miguel de Zárraga, General Medical Manager, from the Hospital Valle del Nalón de Langreo in Asturias; we want to thank them sincerely for their collaboration and support.     

Updating Choquet beliefs

We apply Pires’s coherence property between unconditional and conditional preferences that admit a CEU representation. In conjunction with consequentialism (only those outcomes on states which are still possible can matter for conditional preference) this implies that the conditional preference may be obtained from the unconditional preference by taking the Full Bayesian Update of the capacity.     

基于Gauss求积公式的Newton迭代法

利用Gauss数值积分公式构造牛顿迭代法的变形格式,得到牛顿迭代方法的三个新格式,并证明了它们的收敛阶都为3。通过matlab编程进行数值试验,结果表明三个新格式具有较好的收敛速度。它们丰富了非线性方程求根的方法,在理论上和应用上都有一定的价值。     

Reexamination on updating Choquet beliefs

Eichberger et al. (2007)  characterize the full Bayesian update rule for capacities. This paper shows that a conditional preference relation represented by the Choquet expected utility with respect to the updated capacity through the rule does not satisfy the axiom of Conditional Certainty Equivalence Consistency. A counterexample is provided and it is proved that a relaxation of the axiom maintains their results.     

复变函数与积分变换课程教学方法改革与实践

在复变函数与积分变换课程教学中,运用类比式教学方法、探究式教学方法和归纳总结方法,能提高学生的学习兴趣,提高学习效果。     

预应力混凝土简支梁设计与分析

结合某一办公楼屋面预应力钢筋混凝土梁的设计,介绍了预应力梁的工作机理,进行了该梁的截面和材料的选取及配筋计算,采用ANSYS有限元软件进行了预应力钢筋混凝土梁的挠度验算,最后验算了简支梁的裂缝,可为初级设计人员的设计提供参考和借鉴。     

RELAXED UTILITY MAXIMIZATION IN COMPLETE MARKETS

For a relaxed investor—one whose relative risk aversion vanishes as wealth becomes large—the utility maximization problem may not have a solution in the classical sense of an optimal payoff represented by a random variable. This nonexistence puzzle was discovered by Kramkov and Schachermayer (1999) , who introduced the reasonable asymptotic elasticity condition to exclude such situations. Utility maximization becomes well posed again representing payoffs as measures on the sample space, including those allocations singular with respect to the physical probability. The expected utility of such allocations is understood as the maximal utility of its approximations with classical payoffs—the relaxed expected utility. This paper decomposes relaxed expected utility into its classical and singular parts, represents the singular part in integral form, and proves the existence of optimal solutions for the utility maximization problem, without conditions on the asymptotic elasticity. Key to this result is the Polish space structure assumed on the sample space.     

市场经济下科技进步与经济发展互动综合评价研究

基于模糊积分法,对我国市场经济运行机制下科技进步与经济互动机制进行了综合评价,测算结果表明:市场经济下科技进步对经济的作用机制、经济对科技进步的作用机制以及二者协同机制的运行绩效分别为0.70408949、0.69610579和0.75404855,科技进步与经济互动机制运行总绩效值为0.715478,处于良好水平。     

On the path-dependence of economic growth

The cumulated growth of an economy during a period of time depends on the whole economical history during this period and not only of the situation at the beginning and at the end of the interval. However, if some constraint is made on the set of possible economies, this phenomenon of history-dependence may disappear. We give a simple necessary and sufficient condition on the constraint for this to happen, generalizing results of Samuelson–Swamy and Hulten. Our approach is different, based on differential and symplectic geometry. We also solve the same question for a subsector of the economy.