The Use of Microsoft Excel as a User Interface for Biological Simulations

We used Microsoft Excel 4.0 for Windows running on a PC-486 to develop a user interface for two biological simulation models: a lung fluid balance model and a fractal model of the pulmonary circulation. The simulation programs were written in the C programming language, while the user interface was written in the macro language of Excel. The interface builds input data files for the simulation programs and provides a mechanism for displaying relevant information from output files produced from the simulations. Input fields arc partially protected so that the user cannot modify certain portions of the spreadsheet. The Excel interface is used to build models from different available components and to select appropriate parameters for these models. The developed interface was also useful for running models in the batch mode. After selecting changes in lung fluid balance parameters, the interface allows users to find new steady state values by automatically running the model and adjusting initial conditions. Several different graphical options allow users to easily investigate the effects of selecting particular models and parameters. Techniques used in developing our user interface can be extended to most biological simulation programs which manipulate input and output data files.     

Note sul PL/1

PL/1 (Programming Language/1) was drawn up in 1964 to answer the need for a programming language which is independent, not only of the computer, but also of the type of problem handled: it can thus be used for both commercial and scientific problems. Moreover, the language is superior for scientific computations to Fortran IV; it provides also for commercial users logical operations, methods of input, output and data handling which are more prowerful than thoso made available by Cohol. A program written in PL/1, having a modular structure, satisfactorily answers modern programming cotepts; the program can be divided into relocable sections which allow a dynamic utilisation of core storage. Thanks to this characteristic the PL/1 can satisfy the demands of non-sequential operation as, for example, Tele-Processing and Multitask operations. Another interesting possibility of the language is represented by a category of statements designed to give commands to the compiler in order to optimize compilation itself.      

Adding graphics to a high-level programming language

When graphics input/output capabilities are added to a programming language originally designed with a text stream input/output model, various design decisions affect the ease with which the graphics facilities are learned and used by applications programmers. In adding window system facilities to the Icon programming language, some design decisions were made very differently from the conventional wisdom, resulting in substantial benefits for programmers. In addition, some pre-existing Icon language features have proved to be useful in graphics programming.     

A laboratory study of user characteristics and decision-making performance in end-user computing

A laboratory study using a simulated business setting was conducted to examine relationships among user characteristics, DSS usage patterns, and decision-making performance. MBA-student subjects self-selected into one of two categories: (1) “end-user programmers” who chose to use the DSS modeling language to develop personalized decision models, or (2) “command level users” who used only “canned” models and query language retrievals. The results show that early development of personalized decision models was positively related to the end-user's previous computer experience. The findings also support the contention that end-user programming improves decision-making performance. End-user programmers consistently outperformed the command level users in terms of their firm's stock price, market share, and return on assets.     

Constrained predictive control for multivariable systems with application to power systems

Generalized predictive control (GPC) and dynamic performance predictive control (DPC) algorithms are introduced for industrial applications. Constraints on plant input rate, plant absolute input and plant absolute output can be implemented and are demonstrated on an application of these algorithms. A standard quadratic programming algorithm performs the calculation of the optimal control. A MATLAB/Simulink toolbox environment has been developed where controllers can be designed, linear and non-linear plant models can be embedded, discrete- and continuous-time loop parts can be mixed and simulation results can be managed and evaluated by graphical and statistical tools. This package utilises a graphical user interface. Finally, a case study design example is presented where a linear gas turbine model for power generation is examined with constrained GPC and DPC, and the advantages and drawbacks of the approach are the discussed. Copyright © 1999 John Wiley & Sons, Ltd.     

Hierarchical control model for automated manufacturing systems

A mathematical model is presented to determine the hierarchical computer control requirements for a completely automated flexible manufacturing systems. This model can estimate the number and capacity of hierarchical computers needed to control a specified automated manufacturing system. The hierarchical control system is described by the major operating components common to all controlling computers and computer numerical controlled (CNC) machines: central processing unit, memory, input/output and communications. Each of these components is evaluated with respect to its operating speed and capacity. Costs are then determined as a function of the component's processing speed and capacity.A three-tier control system is examined. Starting with the CNC machines' speeds and capacities, each level of the computer hierarchical control system is modeled and related to the next tier by communication and data requirements. The physical machine layout required for a hierarchical control system is discussed. Part scheduling and process information requirements are also addressed. The model's utility is illustrated by an example using a typical manufacturing system.Optimization of this model is readily obtained using standard dynamic programming techniques. Being totally independent of any specific computer hardware technology, the model can be applied to present and future automated manufacturing systems.     

基于EFDC模型的乌东德水库水质模拟推演系统

为实现对乌东德水库蓄水后水质演变过程的定量预测,研发乌东德水库水质模拟推演系统。采用半紧密式集成方式集成功能强大、源代码开放的EFDC模型,通过Java编程语言编制模型和推演系统之间的接口,将水质模拟推演核心计算模型和信息系统串连起来,实现乌东德水库水质模型的联机在线运算。模拟推演系统对EFDC模型输入参数进行抽象,简化输入条件,用户通过修改输入边界条件,可模拟平水、丰水、枯水期,乌东德水库化学需氧量、总磷、总氮等水质因子的沿程变化,在水质模拟推演结果的表达上以地图为主,采用地图加图表的方式展示,形象直观。研发成果实现专业模型软件的业务化运行,方便管理人员和决策者使用。     

Leogo: An Equal Opportunity User Interface for Programming

Leogo is a novel programming environment supporting an ‘equal opportunity’ user interface which allows users to express their programming tasks through any mixture of three concurrently active programming paradigms: by direct-manipulation using ‘programming by demonstration’, by clicking buttons and dragging sliders in an iconic language and by typing commands in a normal text-based language. Equal opportunity ensures that the effects of any interface action are simultaneously displayed across each of the three paradigms—input expressions in one paradigm cause output of equivalent expressions in the other two paradigms. Leogo is designed to promote programming skills in primary and junior schools, but the interface properties it demonstrates are applicable to a wide range of novel programming environments. Leogo's motivation, design, development and preliminary usability study are described.     

A zero-base budgeting process with goal programming feedback

This paper describes the decision process used to establish the annual budget for allocating general fund revenues to non-revenue generating service activities of a city. This process combines zero-base budgeting (ZBB) and goal programming. The goal programming model formalizes the relationship between the ZBB decision packages specified by city departmental needs and the planning issue goals identified by either the city council, the city administrative staff or a citizens' survey. A budget committee reviews input data, forms the model and uses its output to revise budget inputs. The goal programming model provides a format for (1) effectively evaluating budget assumptions, (2) consistently representing the relationships between the ZBB decision packages and the city planning issues, and (3) quantifying and evaluating the contribution made by the decision packages toward satisfying the planning issue goals.     

基于PL/SQL的批量处理应用的性能优化策略

Oracle数据库系统是目前企业应用最广泛的大型关系数据库管理系统.PL/SQL是Oracle对结构化查询语言SQL扩展的过程性语言,利用其设计和开发触发器、视图、存储过称、包以及函数等实现对数据库的数据处理.在很多企业应用架构设计中,会采取Oracle端存储过程实现一些用户交互少、逻辑复杂和涉及数据量大的批量处理,使得数据库具备了数据存储和业务处理的双重角色.但是在这种应用中,随着数据量的不断增加,如何保证存储过程的性能非常关键.本文结合中国民航国际客运收入管理系统海外版性能优化的成功实践,简要介绍了Oracle的OEM工具和AWR报告两个发现性能问题的工具,并从代码结构调整降I/O、临时表和模拟多线程三方面总结了基于PL/SQL的批量处理应用的性能优化策略,为采用此类架构设计的开发人员和运维人员提供持续优化的思路.     

Book Reviews

This book is a first student text for a course that might be titled "Introduction to Data Processing Systems." As such, the book attempts to cover a broad range of topics. The following summary gives an idea of this coverage. Chapters 1 and 2 provide an historical introduction to stored-program computers with examples of first-, second-, and third-generation machines. The distinctions among hardware, software, and firmware are also introduced. Chapter 2 continues with the functional organization of an EDP system and a discussion of the CPU, main memory, secondary memory, and input/output devices. Chapter 3 covers data representation and coded character sets for various media. Chapter 4 deals with input/output media, and Chapter 5 gives the characteristics of magnetic core storage, semiconductor storage, magnetic drums, and magnetic disks. Chapter 6 considers the CPU and floating-point representation of numbers. Chapters 7 and 8 discuss input/output operations and devices. Chapter 9 mentions minicomputers and microcomputers and introduces the notion of a flowchart. Chapters 10 and 11 introduce techniques for program construction. Structured programming, instruction modification, and address modification are considered as programming techniques. Programming languages including machine language, symbolic language, and such high-level programming languages as Fortran, WATTIV, Cobol, PL/I, PL/C, Basic, APL, and RPG are discussed. Data bases are covered in Chapter 13. Operating systems and Job Control Language are covered in Chapter 14. In Chapter 15, the author considers system concepts such as multiprogramming, multiprocessing, real-time operation, timesharing operation, and virtual storage concepts.     

Modeling of storage properties of higher-level languages

The role of storage in the characterization of higher-level programming languages is discussed. Assignment, in particular, has significantly different meaning in different languages, which can hardly be understood without reference to an underlying model of storage. A general storage model is sketched which can be specialized to a model of ALGOL 68 or of PL/I storage. The same model is used to discuss language features allowing highly flexible data structures.Revised version of a paper presented at the ACM Symposium on Data Structures in Programming Languages, University of Florida, Gainesville, February 25–27, 1971.     

Composition of Constraint,Hypothesis and Error Models to improve interaction in Human–Machine Interfaces

Although there are many tasks where output strings are automatically generated from a set of evidence, they are not perfect and human intervention is often required to correct the result. In this paper we present a generic Symbol Input Interaction Method for Human–Machine Interfaces that combines multi-source information: an input Hypothesis Model, an Error Model, a Constraint Model and a user interaction scheme.We use Weighted Finite-State Transducers (WFSTs) to represent the different sources of information available: the initial hypotheses, the possible errors, the constraints imposed by the task (interaction language) and the user input. The fusion of these models to find the most probable output string can be performed efficiently by using carefully selected transducer operations. The proposed system initially suggests an output based on the set of hypotheses, possible errors and Constraint Models. Then, if human intervention is needed, a multimodal approach, where the user input is combined with the aforementioned models, is applied to produce, with a minimum user effort, the desired output. This approach offers the practical advantages of a de-coupled model (e.g. input-system + parameterized rules + post-processor), keeping at the same time the error-recovery power of an integrated approach, where all the steps of the process are performed in the same formal machine (as in a typical HMM in speech recognition) to avoid that an error at a given step remains unrecoverable in the subsequent steps. After a presentation of the theoretical basis of the proposed multi-source information system, its application to two real world problems, as an example of the possibilities of this architecture, is addressed. The experimental results obtained demonstrate that a significant user effort can be saved when using the proposed procedure. A simple demonstration, to better understand and evaluate the proposed system, is available on the web https://demos.iti.upv.es/hi/.     

Three simulation approaches to queueing studies using GASP IV

Simulation modeling can be constrained by the simulation language with which you are familiar. GASP IV eliminates many constraints by combining discrete and continuous concepts into one language.This paper discusses the simulation modeling philosophy as implied by the GASP IV simulation language. Three models representing different conceptualizations of queueing situations will be developed and the GASP IV code required to obtain a simulation program for each of the models will be described. No attempt will be made to present GASP IV, as it is fully documented [1] and is currently running on a wide variety of computers that have FORTRAN IV compilers.^† Also, no attempt will be made to discuss the advantages of simulation in studying queueing situations or a comparison of simulation languages. These topics are covered extensively in texts on applied operations research and simulation techniques. This paper provides a comparison of approaches to modeling and demonstrates the implementation of queueing models using GASP IV.The inherent capability of GASP IV to provide a structure in which diverse modeling approaches to queueing situations can be used illustrates the broad modeling persepective offered to the GASP IV user. GASP IV is the only well-documented simulation language available for obtaining discrete, continuous or combined models of systems.^†     

cxterm: A Chinese terminal emulator for the X window system

Computing involving data in a logo-syllabic oriental language like Chinese is more difficult than in English. Many attempts have been made to develop bilingual or multilingual processing systems.^1–3 Most of them are based on microcomputers like the IBM-PC. With the widespread use of workstations and window systems, much better multi-lingual processing environments can be provided. This paper describes the design and implementation of the program cxterm, a Chinese terminal emulator for the X Window System. We discuss the representation of multi-byte international characters, the problems of Chinese character input and output, the pros and cons of various approaches, and the design decisions for cxterm. A feature of cxterm is its independence of input methods. A user can incorporate new input methods into cxterm at run-time, without changing the program code. We also compare our approach with related work in multi-lingual input/output in X, and describe how cxterm performs better in terms of efficiency, flexibility, and user-friendliness.     

三维视景仿真系统中仿真过程管理的研究

三维视景仿真系统的仿真过程管理一直是计算机图形学领域的热点之一。三维视景仿真系统的研究主要集中在虚拟环境的真实性方面,仿真过程管理的研究还没有被很好地解决。文中按照功能将三维虚拟视景仿真系统分为七个模块：数据输入、键盘输入、配置文件、消息映射、场景控制、仿真环境显示、数据记录;又从用户角度划分出三个模块：输入模块、处理模块和输出模块。同时,文中提出了配置文件和三维模型XML描述两种关键方法,分别用来存储仿真环境相关数据和简化模型调用方式,提高了虚拟仿真系统的通用性。此方法在三维视景仿真系统的开发过程中成功地进行了应用。     

X-Base PL/SQL异常处理的设计与实现

X-Base PL/SQL是一种过程式数据库编程语言,常用于数据库服务器端应用程序的开发。该文讨论了X-Base PL/SQL引擎中异常处理模块的设计思想和实现技术。鉴于Oracle数据库管理系统是数据库产品事实上的标准,还有其在全球的广泛应用,X-Base PL/SQL需要兼容Oracle PL/SQL 8i的异常处理机制。     

CHEMCAD中二次开发工具UAM的应用

UAM(user added modules)是CHEMCAD强大的二次开发工具,以C 为编程语言,制成USBADD.DLL.本文拓展UAM对混合编程语言的应用,开发了SO2转化反应器平推流模型,并根据混合语言调用约定,用现成的Fortran语言编制的微分方程求解程序Dlsode.for,制作了Dlsode.dll,以供UAM调用.本文的SO2转化反应器模拟结果与设计结果一致.应用混合编程语言使得开发UAM更灵活方便,进一步增强CHEMCAD对复杂、特殊流程的模拟、设计、优化的能力.