Abstract:By using mixed triangle series,this paper discusses the calculation of rectangular stiffened plates with simply supported edge along direction of stiffeners under several local loads,such as uniform load on local rectangular area,concentrated force,concentrated moment of couple,line loads,line moments of equal and some equivalent concentrated forces acting on a line with equaldistance among them.All analytical solutions of both displacements and internal forces are derived.A numerical example to treat an engineering problem is given.

Abstract:This paper analyses in detail the dynamic stability of thedual-excited synchronous generators with non-damping windings,and sets up theundamental equations and the linearized mathematical model for small distur- bance analysis.By an example with computer results,the paper also compareshe difference of the dynamic stabilities between the single-and dual-excited synchronous machines,which explains that the dual-excited synchronous gene- rators can increase the dynamic stability of machines under certain conditions.

Abstract:This paper applies the covering method to the isoparametrictransitional elements of movable boundary nodes.The general shape functionormulas for quadrilateral elements and a convenient method to calculate the local node coordinate parameters are also introduced.The general formulas can be extended to space hexahedron elements.

Abstract:函数迭代法,对p类定解条件的常系数线性发展方程柯西问题,推出了算子级数解的公式.本文在此基础上首先改进了原问题的求解公武,然后将p类解条件推广到C类解条件,并得到相应的求解公式.

Abstract:本文介绍了用Bernstein多项式来逼近函数f(x),它们具有同样的单调性及凹凸性,所以十分便于几何外形设计.Bézier利用Bernstein多项式良好的几何逼近性质,定义了Bézier曲线的两种形式:即用特征多边形的顶点表示的和用特征多边形的边表示的.本文推出用矩阵形式表示的Bézir曲线,并推导几个低次的Bézier曲线.

Abstract:This paper introduces how to compile the mathematic model ofeighth and sixteenth order magic square and how to change twofold magic squ-are problem into onefold magic square problem.The twofold magic square is made by solving liner equations and thus the difficulty of making the twofoldmagic square is reduced.

Abstract:This paper presents the structure and main function of a methanealarm and power-off control device controlled by a single-chip microcomputer,which is first used in China.This paper mainly discusses the circuitry and work-ing principle of a computer and how to solve some special problems when the single chip microcomputer is used in a coal mine where methane exists.

Abstract:This paper studies the performance of a gas-Iiquid-solid fluidizedbed bioreactor(FBB)for the slaughter treatment.The results show that the COD removal rate is higher than 80% when COD concentration in the influent waste-water is about 1000mg/1 and the hydrauIic residence time(HRT)is 124.5 minutes.n the experiments,the crushed granular shale used as media in FBB has advan-tages of slight weight,easy fluidization,ease of attaching by microbes and cheap-ness.

Abstract:This paper studies the optimization on the position of bearing-points in space trusses supported by four columns,taking the cross-sectionalareas of members,the positions of bearing-points and heights of space trusses as the design variables,and the weight of structures as the objective function.After a lot of calculation,the parameters of optimal cantilever lengths and heights of space trusses supported by four columns are presented.

Abstract:By introducing the span-to-height ratio,this paper deduces wo evaluating equations of shear strength of simple reinforced concrete beamwith stirrups and under uniform loads.This makes the shear stressing concept consistent with the evaluating equations,thus improves the evaluating equationsof shear strength of the New Code.Two equations are provided with auto-regulating function on shear strength for a cross section of beam.They aresimple and convenient in evaluation.The working time used for design is not increased and 10% of stirrups is economized in frequent conditions of span-to-height ratio.

Abstract:本文主要讨论了Hilbert空间上带不等式约束的非凸规划的解与Lagrange式鞍点之间的关系.利用闭包函数作为工具,在此条件,存在(x_0,μ_0)conv(epif))且在x_0∈domf条件下,证明了Lagrange式存在鞍点是该非凸规划有解的必要条件.

Abstract:目前结构设计中使用的无粘结顶应力筋极限应力计算式均为经验公式.由于这些经验公式所依据的统计数据系来自试验条件单一的对称加荷简支构件,所以就不适用于悬臂类一梁非对称变形构件中无粘结筋极限应力的计算.本文推导出了悬臂构件中无粘结筋极限应力的计算公式,井对单跨构件中非对称变形对无粘结筋极限应力的影响从理论上进行了分析,为无粘结预应力非对称变形构件的抗弯强度设计提供了关键变量——无粘结筋极限应力的实用计算方法.