Verification of Procedural Programs via Building their Generalized Nets Models

Магдалина Василева Тодорова - В статията е описан подход за верификация на процедурни програми чрез изграждане на техни модели, дефинирани чрез обобщени мрежи. Подходът интегрира концепцията “design by contract” с подходи за верификация от тип доказателство на теореми и проверка на съгласуваност на модели. За целта разделно се верифицират функциите, които изграждат програмата относно спецификации според предназначението им. Изгражда се обобщен мрежов модел, специфициащ връзките между функциите във вид на коректни редици от извиквания. За главната функция на програмата се построява обобщен мрежов модел и се проверява дали той съответства на мрежовия модел на връзките между функциите на програмата. Всяка от функциите на програмата, която използва други функции се верифицира и относно спецификацията, зададена чрез мрежовия модел на връзките между функциите на програмата.

Teaching Subroutines: As Early as Possible

Students on introductory courses in programming languages often experience difficulty understanding the basic principles of procedural programming. In this paper we discuss the importance of early understanding of the subroutine mechanism. Two approaches for self-training – static and dynamic - are presented and compared. The static approach is appropriate for written text in paper textbook. The dynamic approach is suitable for interactive training using a computer. An interactive module was developed for teaching subroutines.

Review and Outlooks of the Means for Visualization of Syntax Semantics and Source Code. Procedural and Object Oriented Paradigm – Differences

In the article, we have reviewed the means for visualization of syntax, semantics and source code for programming languages which support procedural and/or object-oriented paradigm. It is examined how the structure of the source code of the structural and object-oriented programming styles has influenced different approaches for their teaching. We maintain a thesis valid for the object-oriented programming paradigm, which claims that the activities for design and programming of classes are done by the same specialist, and the training of this specialist should include design as well as programming skills and knowledge for modeling of abstract data structures. We put the question how a high level of abstraction in the object-oriented paradigm should be presented in simple model in the design stage, so the complexity in the programming stage stay low and be easily learnable. We give answer to this question, by building models using the UML notation, as we take a concrete example from the teaching practice including programming techniques for inheritance and polymorphism.

The Technology of Programming for a Cluster Computer by the Remote Terminal with OS Windows

The problem of preparation of a program to perform it on multiprocessor system of a cluster type is considered. When developing programs for a cluster computer the technology based on use of the remote terminal is applied. The situation when such remote terminal is the computer with operational system Windows is considered. The set of the tool means, allowing carrying out of editing program texts, compiling and starting programs on a cluster computer, is suggested. Advantage of an offered way of preparation of programs to execution is that it allows as much as possible to use practical experience of programmers used to working in OS Windows environment.

Data Flow Analysis and the Linear Programming Model

* The research is supported partly by INTAS: 04-77-7173 project, http://www.intas.be

Development of Educational Ontology for C-Programming

Development of educational ontologies is a step towards creation of sharable and reusable adaptive educational systems. Ontology as a conceptual courseware structure may work as a mind tool for effective teaching and as a visual navigation interface to the learning objects. The paper discusses an approach to the practical ontology development and presents the designed ontology for teaching/learning C programming.

Programming Paradigms in Computer Science Education

Main styles, or paradigms of programming – imperative, functional, logic, and object-oriented – are shortly described and compared, and corresponding programming techniques are outlined. Programming languages are classified in accordance with the main style and techniques supported. It is argued that profound education in computer science should include learning base programming techniques of all main programming paradigms.

Quality Assurance in Extreme Programming

Our previous research about possible quality improvements in Extreme Programming (XP) led us to a conclusion that XP supports many good engineering practices but there is still place for refinements. Our proposal was to add dedicated Quality Assurance (QA) measures, which should be sufficiently effective and at the same time simpler enough in the context of XP. This paper intends to analyze the possibilities for an effective way for applying approved quality assurance practices to XP. The last should not affect negatively to the process and in the meantime must lead to better quality assurance. We aim to make changes to XP that even if would slow down a bit the development process, will make it more suitable for widest range of projects including large and very large projects as well as life critical and highly reliable systems.

Virtual Instruments – Functional Model, Organization and Programming Architecture

∗ Thematic Harmonisation in Electrical and Information EngineeRing in Europe,Project Nr. 10063-CP-1-2000-1-PT-ERASMUS-ETNE.

Educational Games for Learning Programming Languages

A concept of educational game for learning programming languages is presented. The idea of learning programming languages and improving programming skills through programming game characters’ behavior is described. The learning course description rules for using in games are suggested. The concept is implemented in a game for learning C# programming language. A common game architecture is modified for using in the educational game. The game engine is built on the base of the graphical engine Ogre3D and extended with game logic. The game has been developed as an industry level commercial product and is planned for sale to educational institutions.

Development of Variational Thinking Skills in Programming Teaching

The paper presents an example of methodological approach to the development of variational thinking skills in teaching programming. Various ways in solving a given task are implemented for the purpose. One of the forms, through which the variational thinking is manifested, is related to trail practical actions. In the process of comprehension of the properties thus acquired, students are doing their own (correct or incorrect) conclusions for other, hidden properties and at the same time they discover possibilities for new ways of action and acquiring of new effects. The variability and the generalizing function of thinking are in a close interrelation, and their interaction to a great extend determines the dynamics of the cognitive activity of the student.

Integer Programming Approach to HP Folding

One of the most widely studied protein structure prediction models is the hydrophobic-hydrophilic (HP) model, which explains the hydrophobic interaction and tries to maximize the number of contacts among hydrophobic amino-acids. In order to find a lower bound for the number of contacts, a number of heuristics have been proposed, but finding the optimal solution is still a challenge. In this research, we focus on creating a new integer programming model which is capable to provide tractable input for mixed-integer programming solvers, is general enough and allows relaxation with provable good upper bounds. Computational experiments using benchmark problems show that our formulation achieves these goals.

Method of Linear Programming as an Idea for High School Curriculum

2010 Mathematics Subject Classification: 97D40, 97M10, 97M40, 97N60, 97N80, 97R80

A Language for Compositional Programming: A Rationale and Design

Бойко Бл. Банчев - Представена е обосновка и описание на език за програмиране в композиционен стил за опитни и учебни цели. Под “композиционен” имаме предвид функционален стил на програмиране, при който пресмятането е йерархия от композиции и прилагания на функции. Един от данновите типове на езика е този на геометричните фигури, които могат да бъдат получавани чрез прости правила за съотнасяне и така също образуват йерархични композиции. Езикът е силно повлиян от GeomLab, но по редица свойства се различава от него значително. Статията разглежда основните черти на езика; подробното му описание и фигурноконструктивните му възможности ще бъдат представени в съпътстваща публикация.

A Software Platform for Teaching Programming with Grading Systems

Красимир Манев, Милослав Средков, Петър Армянов - Състезателните системи (СС) са незаменимо средство за организация на състезания по програмиране. Напоследък СС се използват и в обучението по програмиране. В статията е предложена платформа, която да интегрира възможностите на СС, създадени или използвани от авторите. Целта е изграждането на проста и ефективна среда за обучение по програмиране, подпомагаща учебния процес. Специфицирани са основните елементи на платформата, като резултат от предходно изследване, и една нейна възможна архитектура.