线性方程组在工作流相关问题中的应用

为解决工作流中的模型正确性验证、资源分配、活动实例选择等相关问题,提出一种采用建立方程组的求解算法。该算法通过建立方程组描述工作流中的活动结构、资源分配、时间限制等约束条件,建立目标函数用于描述流程的最优目标,求解方程组得到资源分配的最优方案。通过建立等价关系对流程中的活动集合进行划分,再根据约束方程和目标函数求解得出流程的路径选择最佳方案。该算法确保了整个流程的正确性和完整性,实现了流程结构上和性能上的优化。     

A higher order method for multiple zeros of nonlinear functions

A method of order three for finding multiple zeros of nonlinear functions is developed. The method requires two evaluations of the function and one evaluation of the derivative per step.     

Book reviews

THE BRAIN AND BEHAVIORAL SCIENCES (ISSN 0140-525x).Published quarterly by Cambridge University Press (£35.00).

COMPUTATIONAL PROBABILITY AND SIMULATION by Sidney J.Yakowitz pub. Addison-Wesley Pub. Co. Inc., 1977, pp. 240, £10.00 paperbound £18.00 hardnbound.

THE WORLD FERTILITY SURVEY JAN-DEC 1977-ANNUAL REPORT.

COMPSTAT LECTURES I. LECTURES IN COMPUTATIONAL STATISTICS, Ed. by Horst Skarabis and Peter Sint 1978. 132 pages. Bound, pub. Physica-Verlag, Wurzburg, Germany (DM30).

COMPSTAT 1978. PROCEEDINGS OF 3RD SYMPOSIUM IN COMPUTATIONAL STATISTICS LEIDEN 1978, Ed. by L. C. A.

Corsten and J. Hermans, 1978, 538 pages, Bound, pub. Physica-Verlag, Germany (DM59).     

A third-order convergent iterative method for solving non-linear equations

In this paper, we present and analyse a new predictor-corrector iterative method for solving non-linear single variable equations. The convergence analysis establishes that the new method is cubically convergent. Numerical tests show that the method is comparable with the well-known existing methods and in many cases gives better results.     

Parameters of the Mass-Transfer Through the Reverse Osmosis Polysulphonamid Membrane of the Binary Aquatic Solutions of Salts

Abstract

Experimental data of mass transfer through the reverse osmosis polysulfonmide membrane of binary aqueous solutions of salts are compared with the predictions of phenomenological equations of mass transfer.     

Simulations of four independent groups of hamiltonian circuited unknowns in the numerical solutions of elliptic partial differential equations

Past experiments on Hamiltonian circuited simulations of the partial differential equation of the Poisson type have indicated the influences of the Hamiltonian circuits on algebraic structures of coefficients matrices. The need to tend to the usage of finite difference schemes is also observed. A certain Hamiltonian circuit is found to enable the decomposition of the space of simulated points into two subspaces. This paper reports that the space can in fact be separated into four subspaces. Numerical simulations are carried out using a 7-point finite difference star. The results are compared with those obtained when the simulated points are divided into only two disjoint sets.     

边坡稳定性分析最小二乘法

利用经典土压力理论设定合理土条推力线位置,对土条底滑面采用摩尔-库伦破坏准则,根据静力平衡及力矩平衡条件建立线性超定方程组,应用MATLAB软件基于最小二乘法原理对此方程组求解,得到比较精确的安全系数。该法从设定合理土条推力线位置出发,避免了对条间力函数的不合理设定,采用MATLAB求解线性超定方程组得解,克服了求解非线性方程组不能迭代收敛得解的缺点,经算例验证其在精度方面比较可靠,对于评价边坡的稳定性具有参考意义。     

Analytic heat and mass transfer of the mixed hydrodynamic/thermal slip MHD viscous flow over a stretching sheet

In this paper, the heat and mass transfer characteristics of the magnetohydrodynamic (MHD) viscous flow over a permeable stretching surface is solved analytically. The flow considered is under both the hydrodynamic and thermal slip conditions. The magnetohydrodynamic flow and heat transfer of an electrically conducting fluid, taking into account the effects of Joule and viscous dissipation, internal heat generation/absorption, work done due to deformation and thermal radiation is studied. The solution is expressed in a closed form equation and is an exact solution of the full governing Navier-Stokes and energy equations. Thermal transport is analyzed for two types of non-isothermal boundary conditions, i.e. prescribed surface temperature (PST) and prescribed surface heat flux (PHF) varying as a power of the distance from the origin. Results for some special cases of the present analysis are in excellent agreement with those existing in the literature. The effects of various physical parameters, such as magnetic parameter, thermal radiation parameter, heat source/sink parameter, Prandtl number, Eckert number and suction/injection parameter on the velocity and temperature profiles, skin friction coefficient and Nusselt number are examined and discussed in detail. Results show that there is only one physical solution for any combination of the slip together with all the parameters. The velocity/shear stress profiles and the temperature/heat transfer profiles are greatly influenced by these parameters.     

机构综合的混沌搜索自适应入侵遗传算法研究

将生物系统中"入侵"的概念引入遗传算法,提出机构综合排斥二周期点优化求解的一种基于混沌搜索自适应入侵遗传算法.该算法动态地引入入侵种群,并利用混沌搜索产生入侵个体.入侵种群的扩散使优良基因得以在个体中传播,优化了种群的基因构成,能够促使种群跳出局部最小,并向全局优化方向进化,从而有效避免了遗传算法的早熟现象.将该算法应用排斥二周期点优化求解,实例表明该算法具有较快的收敛速度和较强的寻优能力,能够快速求出机构综合问题非线性方程组全部解.     

飞机蒙皮修理补片对气动特性的影响分析

利用欧拉方程计算了飞机机翼特殊部位蒙皮受损修补后,修理补片对气动特性的影响,并进行了粘性修正,从而为优化飞机蒙皮的实际修理工作提供了参考指标,具有较大的实际意义。