Algorithm + strategy = parallelism

1998 ◽  
Vol 8 (1) ◽  
pp. 23-60 ◽  
Author(s):  
P. W. TRINDER ◽  
K. HAMMOND ◽  
H.-W. LOIDL ◽  
S. L. PEYTON JONES
Keyword(s):  
Large Scale ◽  
Higher Order ◽  
Parallel Programs ◽  
Divide And Conquer ◽  
Parallel Applications ◽  
Engineering System ◽  
Evaluation Strategies ◽  
Wide Range ◽  
Higher Order Functions ◽  
Parallel Behaviour

The process of writing large parallel programs is complicated by the need to specify both the parallel behaviour of the program and the algorithm that is to be used to compute its result. This paper introduces evaluation strategies: lazy higher-order functions that control the parallel evaluation of non-strict functional languages. Using evaluation strategies, it is possible to achieve a clean separation between algorithmic and behavioural code. The result is enhanced clarity and shorter parallel programs. Evaluation strategies are a very general concept: this paper shows how they can be used to model a wide range of commonly used programming paradigms, including divide-and-conquer parallelism, pipeline parallelism, producer/consumer parallelism, and data-oriented parallelism. Because they are based on unrestricted higher-order functions, they can also capture irregular parallel structures. Evaluation strategies are not just of theoretical interest: they have evolved out of our experience in parallelising several large-scale parallel applications, where they have proved invaluable in helping to manage the complexities of parallel behaviour. Some of these applications are described in detail here. The largest application we have studied to date, Lolita, is a 40,000 line natural language engineering system. Initial results show that for these programs we can achieve acceptable parallel performance, for relatively little programming effort.

GENERATING MESSAGE-PASSING PROGRAMS FROM ABSTRACT SPECIFICATIONS BY PARTIAL EVALUATION

2005 ◽  
Vol 15 (03) ◽  
pp. 305-320 ◽  
Author(s):  
CHRISTOPH A. HERRMANN
Keyword(s):  
Message Passing ◽  
Cost Model ◽  
Partial Evaluation ◽  
Evaluation Process ◽  
Parallel Programs ◽  
Divide And Conquer ◽  
Parallel Applications ◽  
Communication Structure ◽  
Data Objects ◽  
High Degree

This paper demonstrates how parallel programs with message-passing can be generated from abstract specifications embedded in the functional language MetaOCaml. The functional style permits to design parallel programs with a high degree of parameterization, so-called skeletons. Programmers who are unexperienced in parallelism can take such skeletons for a simple and safe generation of parallel applications. Since MetaOCaml also has efficient imperative features and an MPI interface, the entire program can be written in one language, without the need to use a language interface restricting the set of data objects which could be exchanged. The semantics of abstract specifications is expressed by an interpreter written in MetaOCaml. A cost model is defined by abstract interpretation of the specification. Partial evaluation of the interpreter with a specification, a feature which MetaOCaml provides, yields a parallel program. The partial evaluation process takes time on each MPI process directly before the execution of the application program, exploiting knowledge of the number of processes, the current process identifier and the communication structure. Our example is the specification of a divide-and-conquer skeleton which is used to compute the multiplication of multi-digit numbers using Karatsuba's algorithm.

Structural Outlooks for the OTIS-Arrangement Network

2013 ◽  
pp. 221-231
Author(s):  
Ahmad Awwad ◽  
Jehad Al-Sadi ◽  
Bassam Haddad ◽  
Ahmad Kayed
Keyword(s):  
Linear Algebra ◽  
Wide Class ◽  
High Performance ◽  
Large Scale ◽  
Parallel Computers ◽  
Parallel Architectures ◽  
Divide And Conquer ◽  
Parallel Applications ◽  
Attractive Alternative ◽  
General Method

Recent studies have revealed that the Optical Transpose Interconnection Systems (OTIS) are promising candidates for future high-performance parallel computers. This paper presents and evaluates a general method for algorithm development on the OTIS-Arrangement network (OTIS-AN) as an example of OTIS network. The proposed method can be used and customized for any other OTIS network. Furthermore, it allows efficient mapping of a wide class of algorithms into the OTIS-AN. This method is based on grids and pipelines as popular structures that support a vast body of parallel applications including linear algebra, divide-and-conquer types of algorithms, sorting, and FFT computation. This study confirms the viability of the OTIS-AN as an attractive alternative for large-scale parallel architectures.

A polymorphic library for constructive solid geometry

1995 ◽  
Vol 5 (3) ◽  
pp. 415-442
Author(s):  
J. R. Davy ◽  
P. M. Dew
Keyword(s):  
Higher Order ◽  
Divide And Conquer ◽  
Functional Language ◽  
Constructive Solid Geometry ◽  
Solid Modelling ◽  
General Applicability ◽  
Solid Geometry ◽  
Recurrent Patterns ◽  
Higher Order Functions

AbstractSolid modelling using constructive solid geometry (CSG) includes many examples of stylised divide-and-conquer algorithms. We identify the sources of these recurrent patterns and describe a Geometric Evaluation Library (GEL) which captures them as higher-order functions. This library then becomes the basis of developing CSG applications quickly and concisely. GEL is currently implemented as a set of separately compiled modules in the pure functional language Hope+. We evaluate our work in terms of performance and general applicability. We also assess the benefits of the functional paradigm in this domain and the merits of programming with a set of higher-order functions.

Structural Outlooks for the OTIS-Arrangement Network

2011 ◽  
Vol 3 (2) ◽  
pp. 59-68 ◽  
Author(s):  
Ahmad Awwad ◽  
Jehad Al-Sadi ◽  
Bassam Haddad ◽  
Ahmad Kayed
Keyword(s):  
Linear Algebra ◽  
Wide Class ◽  
High Performance ◽  
Large Scale ◽  
Parallel Computers ◽  
Parallel Architectures ◽  
Divide And Conquer ◽  
Parallel Applications ◽  
Attractive Alternative ◽  
General Method

Recent studies have revealed that the Optical Transpose Interconnection Systems (OTIS) are promising candidates for future high-performance parallel computers. This paper presents and evaluates a general method for algorithm development on the OTIS-Arrangement network (OTIS-AN) as an example of OTIS network. The proposed method can be used and customized for any other OTIS network. Furthermore, it allows efficient mapping of a wide class of algorithms into the OTIS-AN. This method is based on grids and pipelines as popular structures that support a vast body of parallel applications including linear algebra, divide-and-conquer types of algorithms, sorting, and FFT computation. This study confirms the viability of the OTIS-AN as an attractive alternative for large-scale parallel architectures.

Electron microscopy study of reactively sputter-deposited Ti/N films on silicon

1992 ◽  
Vol 50 (2) ◽  
pp. 1362-1363
Author(s):  
V. C. Kannan ◽  
A. K. Singh ◽  
R. B. Irwin ◽  
S. Chittipeddi ◽  
F. D. Nkansah ◽  
...  
Keyword(s):  
Integrated Circuits ◽  
Large Scale ◽  
Hexagonal Phase ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Process Conditions ◽  
Tin Films ◽  
Wide Range ◽  
Fcc Phase ◽  
Circuits Vlsi

Titanium nitride (TiN) films have historically been used as diffusion barrier between silicon and aluminum, as an adhesion layer for tungsten deposition and as an interconnect material etc. Recently, the role of TiN films as contact barriers in very large scale silicon integrated circuits (VLSI) has been extensively studied. TiN films have resistivities on the order of 20μ Ω-cm which is much lower than that of titanium (nearly 66μ Ω-cm). Deposited TiN films show resistivities which vary from 20 to 100μ Ω-cm depending upon the type of deposition and process conditions. TiNx is known to have a NaCl type crystal structure for a wide range of compositions. Change in color from metallic luster to gold reflects the stabilization of the TiNx (FCC) phase over the close packed Ti(N) hexagonal phase. It was found that TiN (1:1) ideal composition with the FCC (NaCl-type) structure gives the best electrical property.

THE SOME QUESTIONS OF AUTONOMOUS MOTION AND MANAGEMENT OF LAND-MOBILE ROBOTIC COMPLEXES FOR UKRAINIAN GROUND FORCESE

2019 ◽  
pp. 53-58
Author(s):  
О. Кravchuk ◽  
V. Symonenkov ◽  
I. Symonenkova ◽  
O. Hryhorev
Keyword(s):  
Large Scale ◽  
Armed Forces ◽  
Distributed Information ◽  
Wide Range ◽  
Highly Effective ◽  
Information Management Systems ◽  
Robotic Devices ◽  
Principles And Standards ◽  
And Control ◽  
The Eu

Today, more than forty countries of the world are engaged in the development of military-purpose robots. A number of unique mobile robots with a wide range of capabilities are already being used by combat and intelligence units of the Armed forces of the developed world countries to conduct battlefield intelligence and support tactical groups. At present, the issue of using the latest information technology in the field of military robotics is thoroughly investigated, and the creation of highly effective information management systems in the land-mobile robotic complexes has acquired a new phase associated with the use of distributed information and sensory systems and consists in the transition from application of separate sensors and devices to the construction of modular information subsystems, which provide the availability of various data sources and complex methods of information processing. The purpose of the article is to investigate the ways to increase the autonomy of the land-mobile robotic complexes using in a non-deterministic conditions of modern combat. Relevance of researches is connected with the necessity of creation of highly effective information and control systems in the perspective robotic means for the needs of Land Forces of Ukraine. The development of the Armed Forces of Ukraine management system based on the criteria adopted by the EU and NATO member states is one of the main directions of increasing the effectiveness of the use of forces (forces), which involves achieving the principles and standards necessary for Ukraine to become a member of the EU and NATO. The inherent features of achieving these criteria will be the transition to a reduction of tasks of the combined-arms units and the large-scale use of high-precision weapons and land remote-controlled robotic devices. According to the views of the leading specialists in the field of robotics, the automation of information subsystems and components of the land-mobile robotic complexes can increase safety, reliability, error-tolerance and the effectiveness of the use of robotic means by standardizing the necessary actions with minimal human intervention, that is, a significant increase in the autonomy of the land-mobile robotic complexes for the needs of Land Forces of Ukraine.

Stirring and aeration system for the upgrading of small waste water treatment plants

1994 ◽  
Vol 29 (12) ◽  
pp. 149-156 ◽  
Author(s):  
Marcus Höfken ◽  
Katharina Zähringer ◽  
Franz Bischof
Keyword(s):  
Waste Water ◽  
Water Treatment ◽  
Large Scale ◽  
Waste Water Treatment ◽  
Water Treatment Plants ◽  
Waste Water Treatment Plants ◽  
Basic Fluid ◽  
Aeration System ◽  
Technical Realization ◽  
Wide Range

A novel agitating system has been developed which allows for individual or combined operation of stirring and aeration processes. Basic fluid mechanical considerations led to the innovative hyperboloid design of the stirrer body, which ensures high efficiencies in the stirring and the aeration mode, gentle circulation with low shear forces, excellent controllability, and a wide range of applications. This paper presents the basic considerations which led to the operating principle, the technical realization of the system and experimental results in a large-scale plant. The characteristics of the system and the differences to other stirring and aeration systems are illustrated. Details of the technical realization are shown, which conform to the specific demands of applications in the biological treatment of waste water. Special regard is given to applications in the upgrading of small compact waste water treatment plants.

Thin structure of heterogeneous and multiphase fluid flows

2012 ◽  
Vol 9 (1) ◽  
pp. 175-180
Author(s):  
Yu.D. Chashechkin
Keyword(s):  
Large Scale ◽  
Fundamental System ◽  
Fluid Flows ◽  
Regular Solutions ◽  
Flow Models ◽  
Group Methods ◽  
Wide Range ◽  
Thin Structure ◽  
Multiphase Fluid ◽  
Complete Solutions

According to the results of visualization of streams, the existence of structures in a wide range of scales is noted: from galactic to micron. The use of a fundamental system of equations is substantiated based on the results of comparing symmetries of various flow models with the usage of theoretical group methods. Complete solutions of the system are found by the methods of the singular perturbations theory with a condition of compatibility, which determines the characteristic equation. A comparison of complete solutions with experimental data shows that regular solutions characterize large-scale components of the flow, a rich family of singular solutions describes formation of the thin media structure. Examples of calculations and observations of stratified, rotating and multiphase media are given. The requirements for the technique of an adequate experiment are discussed.

Current Trends in Biotherapeutic Higher Order Structure Characterization by Irreversible Covalent Footprinting Mass Spectrometry

2019 ◽  
Vol 26 (1) ◽  
pp. 35-43 ◽  
Author(s):  
Natalie K. Garcia ◽  
Galahad Deperalta ◽  
Aaron T. Wecksler
Keyword(s):  
Mass Spectrometry ◽  
Protein Structure ◽  
Protein Interactions ◽  
Quaternary Structure ◽  
Solvent Accessibility ◽  
Higher Order ◽  
Structure Characterization ◽  
Order Structure ◽  
Protein Footprinting ◽  
Wide Range

Background: Biotherapeutics, particularly monoclonal antibodies (mAbs), are a maturing class of drugs capable of treating a wide range of diseases. Therapeutic function and solutionstability are linked to the proper three-dimensional organization of the primary sequence into Higher Order Structure (HOS) as well as the timescales of protein motions (dynamics). Methods that directly monitor protein HOS and dynamics are important for mapping therapeutically relevant protein-protein interactions and assessing properly folded structures. Irreversible covalent protein footprinting Mass Spectrometry (MS) tools, such as site-specific amino acid labeling and hydroxyl radical footprinting are analytical techniques capable of monitoring the side chain solvent accessibility influenced by tertiary and quaternary structure. Here we discuss the methodology, examples of biotherapeutic applications, and the future directions of irreversible covalent protein footprinting MS in biotherapeutic research and development. Conclusion: Bottom-up mass spectrometry using irreversible labeling techniques provide valuable information for characterizing solution-phase protein structure. Examples range from epitope mapping and protein-ligand interactions, to probing challenging structures of membrane proteins. By paring these techniques with hydrogen-deuterium exchange, spectroscopic analysis, or static-phase structural data such as crystallography or electron microscopy, a comprehensive understanding of protein structure can be obtained.

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