THEORETICAL ASPECTS OF VERIFICATION OF BLOCK-SYNCHRONOUS PARALLEL PROGRAMS FOR COMPUTING SYSTEMS BUILT USING BIGDATA TECHNOLOGY

Functional dataflow programming languages are designed to create parallel portable programs. The source code of such programs is translated into a set of graphs that reflect information and control dependencies. The main way of their execution is interpretation, which does not allow to perform calculations efficiently on real parallel computing systems and leads to poor performance. To run programs directly on existing computing systems, you need to use specific optimization and transformation methods that take into account the features of both the programming language and the architecture of the system. Currently, the most common is the Von Neumann architecture, however, parallel programming for it in most cases is carried out using imperative languages with a static type system. For different architectures of parallel computing systems, there are various approaches to writing parallel programs. The transformation of dataflow parallel programs into imperative programs allows to form a framework of imperative code fragments that directly display sequential calculations. In the future, this framework can be adapted to a specific parallel architecture. The paper considers an approach to performing this type of transformation, which consists in allocating fragments of dataflow parallel programs as templates, which are subsequently replaced by equivalent fragments of imperative languages. The proposed transformation methods allow generating program code, to which various optimizing transformations can be applied in the future, including parallelization taking into account the target architecture.

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Evolution of Visualization Methods for Research Publication Collections

Russian Digital Libraries Journal ◽

10.26907/1562-5419-2020-23-4-788-807 ◽

2020 ◽

Vol 23 (4) ◽

pp. 788-807

Author(s):

Alexander Ivanovich Legalov ◽

Igor Alexandrovich Legalov ◽

Ivan Vasilievich Matkovsky

Keyword(s):

Parallel Computing ◽

Parallel Programming ◽

Programming Language ◽

Functional Model ◽

Parallel Programs ◽

Instrumental Support ◽

Static System ◽

Research Publication ◽

Computing Systems ◽

Static Typing

It is proposed to add a static system of types to the dataflow functional model of parallel computing and the dataflow functional parallel programming language developed on its basis. The use of static typing increases the possibility of transforming dataflow functional parallel programs into programs running on modern parallel computing systems. Language constructions are proposed. Their syntax and semantics are described. It is noted that the need to use the single assignment principle in the formation of data storages of a particular type. The features of instrumental support of the proposed approach are considered.

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An open AlgoWiki encyclopedia of algorithmic features: from mobile to extreme scale

Numerical Methods and Programming (Vychislitel'nye Metody i Programmirovanie) ◽

10.26089/nummet.v16r111 ◽

2015 ◽

pp. 99-111

Author(s):

Вл.В. Воеводин

Keyword(s):

Computer Architecture ◽

High Performance ◽

Parallel Programs ◽

Computing Systems ◽

Dependent Part ◽

Software Platforms ◽

Computing Platforms ◽

Extreme Scale ◽

Algorithmic Structure ◽

Performance Computing

Фундаментальная проблема высокопроизводительных вычислений - это необходимость аккуратного согласования структуры алгоритмов и программ с особенностями архитектуры компьютеров. Возможности современных компьютеров велики, но если хотя бы на одном из этапов процесса решения задачи согласования не будет, то и эффективность работы компьютера будет близка к нулю. Основная идея данного проекта состоит в том, что свойства самих алгоритмов никак не зависят от вычислительных систем, существующих сейчас или будущих. Иными словами, детальное описание машинно-независимых свойств алгоритма нужно сделать лишь один раз, после чего оно может быть многократно использовано при реализации данного алгоритма в различных программно-аппаратных средах. Не менее важна и вторая, машинно-зависимая часть данного исследования, которая посвящена описанию особенностей программной реализации алгоритмов с учетом конкретных программно-аппаратных компьютерных платформ. Результатом проекта, которому посвящена данная статья, является открытая энциклопедия AlgoWiki по свойствам алгоритмов и особенностям их реализации для различных компьютерных систем. Умение эффективно работать со свойствами алгоритмов (выделять, описывать, анализировать, интерпретировать) станет широко востребованным уже через несколько лет, что будет верно как для экзафлопсных суперкомпьютерных систем высшего диапазона производительности, так и для всех других компьютерных платформ: от серверных до мобильных. One of the fundamental problems of high performance computing consists in the necessity of a careful matching between the algorithmic structure of parallel programs and the features of a particular computer architecture. The performance capabilities of modern computers are significant; however, the computer's efficiency drastically decreases if such a matching is not achieved even in one of the stages during the process of solving a problem. The AlgoWiki project is based on the fact that the features of algorithms by themselves are not dependent on computing systems. In other words, a detailed description of machine-independent properties of an algorithm should be done only once; after that, this description can be used many times when implementing this algorithm on various hardware/software environments. Also of importance of this project is its machine-dependent part devoted to the description of algorithmic implementation peculiarities with consideration of particular hardware/software platforms. The main result of this project is an open AlgoWiki encyclopedia covering the properties of algorithms and the peculiarities of their implementation on various computing systems. The knowledge of how to reveal, describe, analyze, and interpret the properties of algorithms will become of significant importance in a few years. This conclusion is valid for future exaflop supercomputers and for other computing platforms: from server to mobile devices.

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Software complex for modeling and optimization of program implementation on parallel calculation systems

Open Computer Science ◽

10.1515/comp-2018-0019 ◽

2018 ◽

Vol 8 (1) ◽

pp. 228-234

Author(s):

Valery Bakanov

Keyword(s):

Parallel Computing ◽

Programming Language ◽

Program Implementation ◽

Parallel Programs ◽

Software Environment ◽

Computing Systems ◽

Plan Execution ◽

Modeling And Optimization ◽

Software Complex

Abstract The paper considers the problem of developing rational methods for the creation of a framework (a plan, execution timetable) of parallel programs for real parallel computing systems. To solve this problem, a software environment (software stand) has been developed that allows implementing different strategies for building a framework for parallel programs and assessing the quality of these strategies. The built-in script Lua programming language is used to increase the flexibility of modeling and optimization capabilities. Results of applying some of the proposed strategies for constructing rational plans for parallel programming are outlined.

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Artefact in 20Å-Resolution Electron Images of Negatively Stained Twodimensional Membrane Protein Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053231 ◽

1982 ◽

Vol 40 ◽

pp. 92-93

Author(s):

Douglas L. Dorset ◽

Barbara Moss

Keyword(s):

Electron Scattering ◽

Cross Correlation ◽

Transmission Function ◽

Group Symmetry ◽

Asymmetric Structure ◽

Object Model ◽

Phase Object ◽

Computing Systems ◽

Resolution Electron ◽

Plane Group

A number of computing systems devoted to the averaging of electron images of two-dimensional macromolecular crystalline arrays have facilitated the visualization of negatively-stained biological structures. Either by simulation of optical filtering techniques or, in more refined treatments, by cross-correlation averaging, an idealized representation of the repeating asymmetric structure unit is constructed, eliminating image distortions due to radiation damage, stain irregularities and, in the latter approach, imperfections and distortions in the unit cell repeat. In these analyses it is generally assumed that the electron scattering from the thin negativelystained object is well-approximated by a phase object model. Even when absorption effects are considered (i.e. “amplitude contrast“), the expansion of the transmission function, q(x,y)=exp (iσɸ (x,y)), does not exceed the first (kinematical) term. Furthermore, in reconstruction of electron images, kinematical phases are applied to diffraction amplitudes and obey the constraints of the plane group symmetry.

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Cross-Layer Reliability of Computing Systems

10.1049/pbcs057e ◽

2020 ◽

Keyword(s):

Cross Layer ◽

Computing Systems

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Recovery boiler sootblowers: History and technological advances

TAPPI Journal ◽

10.32964/tj14.1.51 ◽

2015 ◽

Vol 14 (1) ◽

pp. 51-60

Author(s):

HONGHI TRAN ◽

DANNY TANDRA

Keyword(s):

Cfd Modeling ◽

Computing Systems ◽

The Past ◽

Technological Advances ◽

Recovery Boilers ◽

Computational Fluid Dynamics Cfd ◽

Recovery Boiler ◽

Steam Parameters ◽

Insight Into ◽

Deposit Removal

Sootblowing technology used in recovery boilers originated from that used in coal-fired boilers. It started with manual cleaning with hand lancing and hand blowing, and evolved slowly into online sootblowing using retractable sootblowers. Since 1991, intensive research and development has focused on sootblowing jet fundamentals and deposit removal in recovery boilers. The results have provided much insight into sootblower jet hydrodynamics, how a sootblower jet interacts with tubes and deposits, and factors influencing its deposit removal efficiency, and have led to two important innovations: fully-expanded sootblower nozzles that are used in virtually all recovery boilers today, and the low pressure sootblowing technology that has been implemented in several new recovery boilers. The availability of powerful computing systems, superfast microprocessors and data acquisition systems, and versatile computational fluid dynamics (CFD) modeling capability in the past two decades has also contributed greatly to the advancement of sootblowing technology. High quality infrared inspection cameras have enabled mills to inspect the deposit buildup conditions in the boiler during operation, and helped identify problems with sootblower lance swinging and superheater platens and boiler bank tube vibrations. As the recovery boiler firing capacity and steam parameters have increased markedly in recent years, sootblowers have become larger and longer, and this can present a challenge in terms of both sootblower design and operation.

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