Data Flow Program Graphs

Data flow languages form a subclass of the languages which are based primarily upon function application (i.e., applicative languages). By data flow language we mean any applicative language based entirely upon the notion of data flowing from one function entity to another or any language that directly supports such flowing. This flow concept gives data flow languages the advantage of allowing program definitions to be represented exclusively by graphs. Graphical representations and their applications are the subject of this article

Techniques for the realization of ultrareliable spaceborne computers Interim scientific report

Error-free ultrareliable spaceborne computer

Пособие по развитию основных видов речевой деятельности на английском языке для студентов специальностей ФЭИС дневной и вечерней форм обучения

Prokopyuk Olga Vasilievna; Shpudeyko Lyudmila Nikolaevna. English 4 IT. Manual on the development of the main types of speech activity in English for students of the specialties of FEIS full-time and evening forms of educationПособие предназначено для студентов первого курса специальностей: "Вычислительные машины, системы и сети" (1-40 02 01), "Автоматизированные системы обработки информации" (1-53 01 02), "Искусственный интеллект" (1-40 03 01), "Промышленная электроника" (1-36 04 02) (дневное и вечернее сокращенное обучение), "Программируемые мобильные системы" (1-39 03 02), "Программное обеспечение информационных технологий" (1-40 01 01). Данное пособие составлено в соответствии с требованиями учебной программы «Иностранный язык / английский» для студентов указанных специальностей дневной и вечерней форм обучения. Целью данного пособия является изучение профессиональной лексики, повторение и систематизация грамматического минимума, формирование навыков и умений чтения англоязычной документации по компьютерным программам и другой оригинальной литературы по специальности, совершенствование навыков перевода, а также развитие профессиональной устной речи в пределах проработанной тематики. Текстовый материал заимствован из зарубежных источников, его тематика определена программой подготовки специалистов технического профиля

Standardized development of computer software. Part 1: Methods

This work is a two-volume set on standards for modern software engineering methodology. This volume presents a tutorial and practical guide to the efficient development of reliable computer software, a unified and coordinated discipline for design, coding, testing, documentation, and project organization and management. The aim of the monograph is to provide formal disciplines for increasing the probability of securing software that is characterized by high degrees of initial correctness, readability, and maintainability, and to promote practices which aid in the consistent and orderly development of a total software system within schedule and budgetary constraints. These disciplines are set forth as a set of rules to be applied during software development to drastically reduce the time traditionally spent in debugging, to increase documentation quality, to foster understandability among those who must come in contact with it, and to facilitate operations and alterations of the program as requirements on the program environment change

Parallélisation massive des algorithmes de branchement

Les problèmes d'optimisation et de recherche sont souvent NP-complets et des techniques de force brute doivent généralement être mises en œuvre pour trouver des solutions exactes. Des problèmes tels que le regroupement de gènes en bio-informatique ou la recherche de routes optimales dans les réseaux de distribution peuvent être résolus en temps exponentiel à l'aide de stratégies de branchement récursif. Néanmoins, ces algorithmes deviennent peu pratiques au-delà de certaines tailles d'instances en raison du grand nombre de scénarios à explorer, pour lesquels des techniques de parallélisation sont nécessaires pour améliorer les performances. Dans des travaux antérieurs, des techniques centralisées et décentralisées ont été mises en œuvre afin d'augmenter le parallélisme des algorithmes de branchement tout en essayant de réduire les coûts de communication, qui jouent un rôle important dans les implémentations massivement parallèles en raison des messages passant entre les processus. Ainsi, notre travail consiste à développer une bibliothèque entièrement générique en C++, nommée GemPBA, pour accélérer presque tous les algorithmes de branchement avec une parallélisation massive, ainsi que le développement d'un outil novateur et simpliste d'équilibrage de charge dynamique pour réduire le nombre de messages transmis en envoyant les tâches prioritaires en premier. Notre approche utilise une stratégie hybride centralisée-décentralisée, qui fait appel à un processus central chargé d'attribuer les rôles des travailleurs par des messages de quelques bits, telles que les tâches n'ont pas besoin de passer par un processeur central. De plus, un processeur en fonctionnement génère de nouvelles tâches si et seulement s'il y a des processeurs disponibles pour les recevoir, garantissant ainsi leur transfert, ce qui réduit considérablement les coûts de communication. Nous avons réalisé nos expériences sur le problème de la couverture minimale de sommets, qui a montré des résultats remarquables, étant capable de résoudre même les graphes DIMACS les plus difficiles avec un simple algorithme MVC.Abstract: Optimization and search problems are often NP-complete, and brute-force techniques must typically be implemented to find exact solutions. Problems such as clustering genes in bioinformatics or finding optimal routes in delivery networks can be solved in exponential-time using recursive branching strategies. Nevertheless, these algorithms become impractical above certain instance sizes due to the large number of scenarios that need to be explored, for which parallelization techniques are necessary to improve the performance. In previous works, centralized and decentralized techniques have been implemented aiming to scale up parallelism on branching algorithms whilst attempting to reduce communication overhead, which plays a significant role in massively parallel implementations due to the messages passing across processes. Thus, our work consists of the development of a fully generic library in C++, named GemPBA, to speed up almost any branching algorithms with massive parallelization, along with the development of a novel and simplistic Dynamic Load Balancing tool to reduce the number of passed messages by sending high priority tasks first. Our approach uses a hybrid centralized-decentralized strategy, which makes use of a center process in charge of assigning worker roles by messages of a few bits of size, such that tasks do not need to pass through a center processor. Also, a working processor will spawn new tasks if and only if there are available processors to receive them, thus, guaranteeing its transfer, and thereby the communication overhead is notably decreased. We performed our experiments on the Minimum Vertex Cover problem, which showed remarkable results, being capable of solving even the toughest DIMACS graphs with a simple MVC algorithm

Introduction to CAP : A language extension for the specification of pipelined parallel applications

Programming parallel shared- and distributed-memory architectures remains a difficult task. This contribution proposes a methodology for the hierarchical specification of pipelined parallel applications running on shared- as well as distributed-memory architecture. The methodology targets coarse to medium grain parallelism. The CAP methodology (Computer-Aided Parallelization) assumes that parallel hardware works as a factory producing cars. The important part of the analogy is the support for pipelining. Another important feature of the CAP methodology is its hierarchical and compositional nature. The methodology is supported by the CAP language extension to C++. The CAP extension translates to sequential C++ programs for application validation using conventional debuggers, to shared-memory parallel programs based on threads, and to distributed-memory parallel programs communicating using the PVM message-passing library. This contribution presents the CAP methodology, the CAP language extension, as well as an application of the CAP methodology to medical imaging. It also presents the current status of the CAP project

Concurrent program schemes and their logics

AbstractWe define and investigate several classes of concurrent program schemes, including goto schemes and two versions of structured schemes, based on extensions of the regular expressions to trees. The schemes are studied on the first-order, Boolean-variable and propositional levels. We also define and study the dynamic logics based on these classes of schemes, including issues of decidability and axiomatization

A High Performance Parallel Classifier for Large-Scale Arabic Text

Text classification has become one of the most important techniques in text mining. It is the process of classifying documents into predefined categories or classes based on their content. A number of machine learning algorithms have been introduced to deal with automatic text classification. One of the common classification algorithms is the k-Nearest Neighbor (k-NN) which is known to be one of the best classifiers applied for different languages including Arabic language and it is included in numerous experiments as a basis for comparison. Furthermore, it is a simple classification algorithm and very easy to implement since it does not require a training phase that most classification algorithms must have. However, the k-NN algorithm is of low efficiency because it requires a large amount of computational power for evaluating a measure of the similarity between a test document and every training document and for sorting the similarities. Such a drawback makes it unsuitable to handle a large volume of text documents with high dimensionality and in particular in the Arabic language. In our research, we propose to develop a parallel classifier for large-scale Arabic text that achieves the enhanced level of speedup, scalability, and accuracy. The proposed parallel classifier is based on the sequential k-NN algorithm. We test the parallel classifier using the Open Source Arabic Corpus (OSAC) which is the largest freely public Arabic corpus of text documents. We study the performance of the parallel classifier on a multicomputer cluster that consists of 14 computers. We report both timing and classification results. These results indicate that the proposed parallel classifier has very good speedup and scalability and is capable of handling large documents collections. Also, classification results show that the proposed classifier has achieved accuracy, precision, recall, and F-measure with higher than 95%

Selection of a new hardware and software platform for railway interlocking

The interlocking system is one of the main actors for safe railway transportation. In most cases, the whole system is supplied by a single vendor. The recent regulations from the European Union direct for an “open” architecture to invite new game changers and reduce life-cycle costs. The objective of the thesis is to propose an alternative platform that could replace a legacy interlocking system. In the thesis, various commercial off-the-shelf hardware and software products are studied which could be assembled to compose an alternative interlocking platform. The platform must be open enough to adapt to any changes in the constituent elements and abide by the proposed baselines of new standardization initiatives, such as ERTMS, EULYNX, and RCA. In this thesis, a comparative study is performed between these products based on hardware capacity, architecture, communication protocols, programming tools, security, railway certifications, life-cycle issues, etc