基于AutoCAD平台的数控铣削仿真模块的开发

针对XK714铣削系统，以及AutoCAD二次开发工具ObjectARX，介绍了一种数控铣削过程计算机模拟的实现方法，采用面向对象的程序设计方法，对刀具轨迹动态模拟技术进行了分析，在数控自动编程的基础上，详细介绍了数控铣削仿真模块的实现方法，实现了可视化图形交互式数控铣削的模拟。     

线性规划问题的对比教学

对线性规划问题，一般用单纯形法求解。本文探讨了用矩阵及Gauss消元法来处理单纯形法的思想，使学生易于理解、掌握、应用线性规划问题。     

用广义上界算法解大型供应链问题

信息技术和生产率的发展以及全球经济一体化的发展趋势，使供应链成为全世界管理科学的热点.本文在阐述供应链基本数学模型的基础上，系统论述了用改进的广义上界(GUB)算法求解大型供应链问题的计算方法．     

设计指纹签到系统的思考

介绍了实现指纹签到系统中高级语言Visual Basic对底层二进制数据的读取方法，数据的存放方式。详细讲述了用Visual Basic编程的关键技术和方法。同时给出了指纹签到系统的使用效果和应用前景。     

Simulation Study of Aspects of the Classical Hydrogen Atom Interacting with Electromagnetic Radiation: Elliptical Orbits

The present study examines the behavior of a classical charged point particle in near-elliptic orbits about an infinitely massive and oppositely charged nucleus, while acted upon by applied electromagnetic radiation. As recently shown for near-circular orbits, and now extended here to the elliptical case, rather surprising nonlinear dynamical effects are readily produced for this simple system. A broad range of stability-like conditions can be achieved by applying radiation to this classical atom. A perfect balance condition is examined, which requires an infinite number of plane waves representing harmonics of the orbital motion. By applying a scale factor to this radiation, stability-like conditions are produced where periodic variations in semimajor and semiminor axes occur for extended periods of time, before orbital decay eventually takes over due to the effects of radiation reaction. This work is expected to lead to both practical suggestions on experimental ideas involving controlling ionization and stabilization conditions, as well as hopefully aiding in theoretical explorations of stochastic electrodynamics.     

Reasoning with infinite stable models

This paper illustrates extensively the theoretical properties, the implementation issues, and the programming style underlying finitary programs. They are a class of normal logic programs whose consequences under the stable model semantics can be effectively computed, despite the fact that finitary programs admit function symbols (hence infinite domains) and recursion. From a theoretical point of view, finitary programs are interesting because they enjoy properties that are extremely unusual for a nonmonotonic formalism, such as compactness. From the application point of view, the theory of finitary programs shows how the existing technology for answer set programming can be extended from problem solving below the second level of the polynomial hierarchy to all semidecidable problems. Moreover, finitary programs allow a more natural encoding of recursive data structures and may increase the performance of credulous reasoners.     

A functional correspondence between call-by-need evaluators and lazy abstract machines

We bridge the gap between compositional evaluators and abstract machines for the lambda-calculus, using closure conversion, transformation into continuation-passing style, and defunctionalization of continuations. This article is a followup of our article at PPDP 2003, where we consider call by name and call by value. Here, however, we consider call by need.We derive a lazy abstract machine from an ordinary call-by-need evaluator that threads a heap of updatable cells. In this resulting abstract machine, the continuation fragment for updating a heap cell naturally appears as an ‘update marker’, an implementation technique that was invented for the Three Instruction Machine and subsequently used to construct lazy variants of Krivine's abstract machine. Tuning the evaluator leads to other implementation techniques such as unboxed values. The correctness of the resulting abstract machines is a corollary of the correctness of the original evaluators and of the program transformations used in the derivation.     

Modeling and analysis of workpiece stability based on the linear programming method

After being located on a machine bed, a workpiece will be subject to gravity and cutting forces during the machining operation. In order to keep the locating precision as well as the production safety, it is necessary to maintain the workpiece stability. In this paper, a linear programming method is proposed for stability analysis of the workpiece. Based on the linear approximation of the friction cone, a quantitative criterion is established to verify the workpiece stability in association with the rationality of the clamping sequence, magnitude of clamping forces and clamping placement. This criterion allows designers to plan reasonably the clamping sequence, magnitude of clamping forces as well as clamping placement. Compared with existing methods, the main advantage of this approach lies in that the sophisticated computing of contact forces between fixture elements and the workpiece is avoided. In this work, both friction and frictionless cases can be easily taken into account in stability analysis. Mathematical formulations of the method are given and some numerical tests are finally demonstrated to validate the proposed method.     

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）