Abstract:The quality of architectural environment in cities is one of important appraisale standards of material and spiritual civilization. Architectural environment is always regarded as an organic part of architecture and it is thought as a whole in planing and design. Owing to the nature, human communication, sense of overall and nature protection etc., the change of age has emerged in cities. Because we didn't pay attention to it, cities have shown pollution of architectural environment. This paper analyses following problems: cities have undergone historical change during extention, reconstruction and development; cultural inheritance shows the individual character of cities; with the aid of environment of nature and afforestation, the sentiment of architectural environment in cities is improved; architectural environment has limited the scale and visual angle; architectural environment faces the surmountable period.

Abstract:本文给出了钢筋混凝土框架非线性二阶效应电算分析的基本思路及步骤,并以最基本的门式单元框架及封闭式单元框架为对象,系统分析了竖向及水平荷载、梁-柱线刚度比以及柱的细长度等因素对柱控制截面二阶弯矩的影响规律。并以修订后的《混凝土结构设计规范》中的偏心距增大系数η的计算公式为基点,给出了能较准确反映上述两类框架柱控制截面二阶弯矩的当量标准柱长度(计算长度)l_0,以及该当量长度随各影响因素变化的规律及其拟合公式。

Abstract:In this paper, on condition that the production processes in water plant are related with each other, a new coordinative algorithm is presented, using a hierarchical control structure and taking the equivalent efficiency of the pump station as coordinative variable. In this way, the problem of optimal control of the complex delay system is solved. Simulation shows that great energy-saving efficiency may be obtained by the above method.

Abstract:This paper presents a new numerical solution for Neumann problem of Helmholtz equation in R~3. The expression of the solution for this problem is obtained by use of a double layer potential and it leads to a Fredholm boundary integral equation of the first kind. Then, the existence and unicity of the integral equation which is equivalent to the boundary value problem are obtained in a suitable Sobolev space. Finally, a variational form which is equivalent to the integral equation is applied to the construction of a finite element method and the error estimate is given.

Abstract:The lateral structures of frame-shear wall system are simplified into bending beams and shear beams which stiffness can vary in different stages along the building height. The three-dimension stiffness matrix and mass matrix are deduced, and the characteristic equation is established to calculate the tortuous free vibration of the asymmetric system. The method is simple and has satisfactory precision, and it is easily fulfilled in micro-computers.

Abstract:The minimum sizes of specimens that can get effective K_(10) values by 3-point bending, 4-point bending and CT methods are derived on the basis of their notch sensitivity laws and size effect equation of concrete. The results show that the minimum heights of 3-point bending and 4-point bending specimens are very similar to those from Modeer's results, and the minimum height of CT specimen increases as the relative crack length increases.

Abstract:This paper studies the uniqueness of flat solutions on some Fuchsian equations. First, Carleman's estimate for a first order P_sDO is proved, then the uniqueness of the solution of first and second order Fuchsian equations are proved by classic method. Finaly, the uniqueness of t-involutive equations is obtained.

Abstract:Based on analysis of pool boiling characteristics outside low finned tube, this paper describes a simple method, using enhancing shroud to improve the performance of boiling heat transfer outside the low finned tube. The experiment results show that the boiling heat transfer coefficient can be 7-up to 10-fold enhanced by using shroud. The efficiency of a shroud is related to the size of two windows, heat flux and physical characteristics of test fluids.

Abstract:In this paper, a large number of tests are made for studying the model test technique of socketed piles in soft rock, consisting of methods measuring peoperties of model materials, preparing model piles and pressure cells, forming different roughness of model pile, measuring initial lateral pressure,and testing of different types of model piles. According to the regularity and the comparison of the test results, the test method is feasible, from which the behavior of socketed piles in soft rock can be further understood.

Abstract:This paper studies several kinds of motion equations of nonlinear nonholonomic constraint systems. On the basis of the motion equations of the first order nonholonomic system and the theory of the zero factor of matrix multiplying from the left, the general equations of the system without undetermined multipliers is derived. By applying the method to arbitrary order nonholonomic systems, the motion equations of the systems are gained.

Abstract:In this paper, the concept of set-valued maps is introduced. By use of this concept and the superior-inferior structure, the stability of nondominated solutions is discussed in the objection space and decision space.

Abstract:This paper discusses the optimalty condition of a class of nonlinear integer programming and the algorithm to solve this problem.

Abstract:This paper uses simple and clear mathematical proving to expound the fundamental principle,usage and prospect of Monte Carlo method. This paper also gives an example which explains how Monte Carlo method is used for analysing structural reliabilty of engineering.