A universal compiler system based on production rules

This paper describes a compiler system which makes use of production rules for the translation. The source language syntax is defined in terms of a phrase structure grammar. Semantic rules are provided by an extension of the production rules, and special symbols are introduced for this purpose. Recognition of symbol strings is facilitated by a special syntactic filter routine. An example of a simple macro compiler is given to illustrate the basic concepts of the system.     

一种计算工作时间参数新方法

为了编制和优化施工进度计划,计算构成施工项目的各项工作最早开始时间、最迟开始时间、最早完成时间、最迟完成时间、总时差和自由时差等时间参数十分重要.提出了一种计算工作时间参数新方法.该方法以工作完成时间为决策变量,通过建立和求解线性规划模型来得到各种工作时间参数.其建模思路清晰,不需绘制网络图,能用通用办公软件EXCEL求解.模拟计算表明,用该方法与用标准网络计划技术计算出的工作时间参数完全一致.     

Activity graphs: A language for flexible consultation systems

An intelligent decision system (IDS) uses artificial intelligence principles to deliver automated, interactive decision analysis (DA) consultations. Network methods adapted from operations research underlie two key IDS components: influence diagrams and activity graphs. Influence diagrams, which are familiar to DA researchers and practitioners, represent decision problems inevent space. Activity graphs, which are introduced in this paper, represent processes inaction space. While activity graphs can represent any process, we use them as a knowledge-engineering and programming language to represent the process knowledge of skilled decision analysts in the context of a specific class of decisions. This paper defines activity graphs as an extension of directed AND-OR graphs. Anactivity tree is a directed AND-OR tree consisting of nodes, which may contain activities (small computer programs) and connectors that establish logical relationships among nodes and define logical resolution agendas. Anactivity graph is a directed, multiply connected network of activity trees. Activity graphs may involve recursion. Development of the activity graph language is motivated by our desire to enable professional decision analysts — or other experts — with limited advanced programming experience to design and build consultation systems that combine the guidance offered by protocol systems with the flexibility and generality of transaction systems. This paper defines the activity graph language in detail. A simple example illustrates key concepts. The paper also discusses our experience using a computer system that implements activity graphs for developing commercial IDSs.     

A theoretical comparison between the simplex method and the basic line search algorithm

A theoretical comparison between the simplex method (SM) and the basic line search method (BLSA) is presented. The explicit formulae for the upper and lower bounds in the BLSA are provided using SM. Further, it is shown that both methods are operationally equivalent.     

A summary of OR/MS software on microcomputers

This paper provides a summary of some OR/MS software for microcomputers. Lists of packages in many management science techniques are included. A bibliography of other papers is also included. We also summarize the general features of packages in each category. Finally, we mention a few sources to help the reader keep up with the developments in this area.     

A summary of OR/MS software on microcomputers

This paper provides a summary of some OR/MS software for microcomputers. Lists of packages in many management science techniques are included. A bibliography of other papers is also included. We also summarize the general features of packages in each category. Finally, we mention a few sources to help the reader keep up with the developments in this area.     

Optimization using spreadsheets on a microcomputer

This paper discusses the advantages of using spreadsheets for problem specification and report generation in optimization projects. It summarizes some of the mathematical programming software which is compatible with popular spreadsheets. A small production planning problem is used to illustrate the steps in input and processing of the results. Two programs are compared in detail.     

Designing Modular Software: A Case Study in Introductory Statistics

Modular programming is a development paradigm that emphasizes self-contained, flexible, and independent pieces of functionality. This practice allows new features to be seamlessly added when desired, and unwanted features to be removed, thus simplifying the software's user interface. The recent rise of web-based software applications has presented new challenges for designing an extensible, modular software system. In this article, we outline a framework for designing such a system, with a focus on reproducibility of the results. We present as a case study a Shiny-based web application called intRo, that allows the user to perform basic data analyses and statistical routines. Finally, we highlight some challenges we encountered, and how to address them, when combining modular programming concepts with reactive programming as used by Shiny. Supplementary material for this article is available online.     

A note on vector network equilibrium principles

An example is given to show that the necessary conditions of Theorem 4.5 [in Chen et al. Math Methods Oper Res 49:239–253, 1999] and Theorem 2.1 (i) [in Goh and Yang Eur J Oper Res 116:615–628, 1999] for (weak) vector equilibrium flows may not hold. New ξ-equilibrium and parametric equilibrium flows are introduced. As a result, necessary and sufficient conditions between a weak vector equilibrium flow and an ξ-equilibrium flow and between a vector equilibrium flow and a parametric equilibrium flow are established.     

A note on article “A tolerance approach to the fuzzy goal programming problems with unbalanced triangular membership function”

Kim and Whang use a tolerance approach for solving fuzzy goal programming problems with unbalanced membership functions [J.S. Kim, K. Whang, A tolerance approach to the fuzzy goal programming problems with unbalanced triangular membership function, European Journal of Operational Research 107 (1998) 614–624]. In this note it is shown that some results in that article are incorrect. The necessary corrections are proposed.     

A note on functions whose local minima are global

In this note, a simple proof of a theorem concerning functions whose local minima are global is presented and some closedness properties of this class of functions are discussed.The authors would like to thank Dr. Tatsuro Ichiishi of CORE for outlining the new proof of Theorem 2.1.This research was done while the author was a research fellow at the Center for Operations Research and Econometrics, University of Louvain, Heverlee, Belgium.     

基于部分基变量的LP问题矩阵算法

基于部分基变量提出了LP问题的矩阵算法. 该算法以最优基矩阵的一个充分必要条件为基础,首先将一个初始矩阵转化为右端项和检验数均满足要求的矩阵,再转为检验数满足要求的基矩阵,最后转化为最优基矩阵.该算法具有使用范围广、计算规模小、计算过程简化、计算机易于实现的优势.矩阵算法的核心运算是求逆矩阵的运算,提出了矩阵算法的求逆问题,讨论并给出了求逆快速算法,该算法充分利用了矩阵算法迭代过程中提供的原来的逆矩阵的信息经过简单的变换得到新的逆矩阵,该算法比直接求逆法计算效率更高.     

A method for solving fuzzy goal programming problems based on MINMAX approach

Narasimhan incorporated fuzzy set theory within goal programming formulation in 1980. Since then numerous research has been carried out in this field. One of the well-known models for solving fuzzy goal programming problems was proposed by Hannan in 1981. In this paper the conventional MINMAX approach in goal programming is applied to solve fuzzy goal programming problems. It is proved that the proposed model is an extension to Hannan model that deals with unbalanced triangular linear membership functions. In addition, it is shown that the new model is equivalent to a model proposed in 1991 by Yang et al. Moreover, a weighted model of the new approach is introduced and is compared with Kim and Whang’s model presented in 1998. A numerical example is given to demonstrate the validity and strengths of the new models.     

A note on duality in disjunctive programming

We state a duality theorem for disjunctive programming, which generalizes to this class of problems the corresponding result for linear programming.This work was supported by the National Science Foundation under Grant No. MPS73-08534 A02 and by the US Office of Naval Research under Contract No. N00014-75-C-0621-NR047-048.     

A method for determining the equilibrium states of dynamic systems

A heuristic method is presented for determining the equilibrium states of motion of dynamic systems, in particular, spacecraft. The method can also be applied to the solution of sets of linear or nonlinear algebraic equations. A positive-semidefinite functional is formed to convert the problem to that of finding those minimum points where the functional vanishes. The process is initiated within a selecteddomain of interest by random search; convergence to a minimum is obtained by a modified Davidon's deflected gradient technique. To render this approach feasible in the presence of constraints, the functional is modified to include penalty terms which cause the functional to approach infinity at the constraint boundaries. Close approximations to solutions near the constraint boundaries are found by applying Carroll's approach in successively reducing the weighting factors of the penalty terms. After finding a minimum, the local domain around this point is eliminated by adding to the functional an interior constraint term, representing the surface under a hypersphere centered at the minimum point. The domain of consideration now becomes the subdomain formed by subtracting the space contained within this hypersphere from the previous domain of interest. Minima are now sought within the remaining space, as before.This paper is derived from research performed by the author while employed by TRW Systems Group, Redondo Beach, California.The author acknowledges the helpful suggestions of Dr. G. Bekey, University of Southern California, and those of Mr. E. A. Quast, Dr. M. P. Scher, and Dr. R. J. Wiley, Dynamics Department, TRW Systems Group, Redondo Beach, California.     

概率约束最优化问题

概率约束最优化问题是随机规划的一类重要问题,在金融、管理和工程计划等领域有广泛的应用. 概率约束优化问题近年来受到了广泛的关注和重视,在应用建模、理论和方法等方面取得了不少重要的进展. 这里主要概述和总结处理概率约束的主要方法和思想,包括凸内逼近方法、情景逼近方法、DC方法和整数规划方法等,并对概率约束最优化的研究前景进行讨论.