Nonlinear programming approaches for an inverse problem in quasibrittle fracture

Characterization of the parameters describing the cohesive crack model is an important and difficult problem. Based on the availability of load-deflection data, obtained from such standard tests as the three-point bending and wedge splitting experiments, we formulate the required parameter identification as a special type of inverse problem. The formulation is in the form of a constrained optimization problem known as a mathematical program with equilibrium constraints characterized, in the present instance, by complementarity conditions involving the orthogonality of two sign-constrained vectors. Due to the difficulty of solving such a mathematical program directly, we investigate a number of numerical algorithms that are all based on solving a series of standard nonlinear programming problems. Computational results, using actual experimental data, are presented to compare the various schemes proposed.     

一个新的线性规划预校正算法

提出了一种新的线性规划预校正算法,预步是取的Ｅｕｌｅｒ方向,算法复杂度为Ｏ（n~(1/2)Ｌ）     

运用多维画法几何理论解决线性规划问题

本文用计算机与多维画法几何理论相结合的方法，对地线性规划问题，给出了一种新的解法，文中包括理论述，计算方法，程序设计及计算实例等。     

Automation, work organization and skills: The case of numerical control

This paper deals with small and medium sized firms. Since the late seventies small and medium sized mechanical engineering firms in France have resorted increasingly to new technologies, and in particular to numerical control. Numerical control has introduced major changes in work organization. On the one hand it tends to reinforce the role of methods of production engineering whatever the type of numerical control may be. Programming is seldom left to the machine operators, except in the case of straightforward machining operations or in machining shops with a strong tradition of highly skilled or artisan labour. Numerical control, on the other hand, does provide more opportunity for collaboration between the workshop and the production engineers. On a workshop level it introduces a more mobile division of labour between programmers, machine setters and operators, which covers everything from the start-up of programs to the supervision of maching operations. The operator may therefore acquire new skills, but this is only possible if there are open-ended training systems available to facilitate the transmission of know-how from the programmers to the machine setters and from the machine setters to the operators, and vice versa. Small and medium sized firms would appear to have a special role to play in developing skills.     

露天矿生产车辆安排计划优化设计

本文结合露天矿车辆生产安排计划的特点,全面分析了车辆安排问题约束条件,构建了基于整数规划的线路车次安排数学模型。利用线性规划对电铲进行初始布点,实现对模型的合理简化,加速模型的求解。考虑到电铲利用率很难达到1,为提高模型最优解的实际应用的可行性,增加了车辆调度的弹性,设置了电铲的最大利用率。为保证电铲有一定的利用率,设置了电铲最小利用率。计算表明本模型具有较好的实用性和通用性。     

Perinatal Obesity Induces Hepatic Growth Restriction with Increased DNA Damage Response,Senescence, and Dysregulated Igf-1-Akt-Foxo1 Signaling in Male Offspring of Obese Mice

Maternal obesity predisposes for hepato-metabolic disorders early in life. However, the underlying mechanisms causing early onset dysfunction of the liver and metabolism remain elusive. Since obesity is associated with subacute chronic inflammation and accelerated aging, we test the hypothesis whether maternal obesity induces aging processes in the developing liver and determines thereby hepatic growth. To this end, maternal obesity was induced with high-fat diet (HFD) in C57BL/6N mice and male offspring were studied at the end of the lactation [postnatal day 21 (P21)]. Maternal obesity induced an obese body composition with metabolic inflammation and a marked hepatic growth restriction in the male offspring at P21. Proteomic and molecular analyses revealed three interrelated mechanisms that might account for the impaired hepatic growth pattern, indicating prematurely induced aging processes: (1) Increased DNA damage response (γH2AX), (2) significant upregulation of hepatocellular senescence markers (Cdnk1a, Cdkn2a); and (3) inhibition of hepatic insulin/insulin-like growth factor (IGF)-1-AKT-p38-FoxO1 signaling with an insufficient proliferative growth response. In conclusion, our murine data demonstrate that perinatal obesity induces an obese body composition in male offspring with hepatic growth restriction through a possible premature hepatic aging that is indicated by a pathologic sequence of inflammation, DNA damage, senescence, and signs of a possibly insufficient regenerative capacity.     

基于分段求解法的电力生产最优化模型分析

针对发电机使用的非线性最优化问题,通过对用户耗电数据进行初步分析和处理后,应用普遍的分段思想以及最优化思想,建立了二次规划模型。运用最优化算法,使每个时间段使用的发电机数量最少,以达到提高效率、降低成本的目的。     

演播室设备自动控制探究

介绍了硬件接口的通信协议,结合本台实际,介绍了在系统灵活控制方面所做的尝试、设备选型、控制功能设计目标,最后给出了详细的设计方法.     

基于ATR技术的有机聚合物二次电光系数的测量

二次电光效应是有机聚合物材料一种重要的电光特性,利用这种特性可以制备有机聚合物电光调制器等电光器件.有机聚合物材料的二次电光系数是衡量其二次电光效应的一个重要参数,其可以用一个6×6阶的张量来表示.利用该张量的对称特性、各个元素之间的已知关系以及折射率椭球公式,本文提出了一种基于衰减全反射(ATR)技术的测量有机聚合物二次电光系数的方法.在测量中,通过选用TM偏振光以及TE偏振光作为测量光束,可以分别获得二次电光系数张量中S11以及S12元素.利用已知关系,可以计算得到S44以及直流克尔系数.从而得到二电光系数张量中所有元素的值.