Yoshikazu Hayase

A problem-solving environment (PSE) for distributed computing

A problem-solving environment (PSE) for a distributed high-performance computing (HPC) is proposed to help users to work on distributed computer environment. When users access and use distributed computers for scientific computations, the PSE tells users which computers are available and appropriate for their specific application software by using hardware and software informations specified. Then, the users deploy their software on the distributed computer systems. The software, which can be used later or available for other users, is plugged and pooled in the PSE application pool in order to enhance their reusability. The problem-solving process work flow (WF) is also stored in a case-based database (DB) in the PSE and then the case DB can be used to suggest a WF for users to solve their problems. The PSE may open a new flexible HPC environment.

Visual Steering of the Simulation Process in a Scientific Numerical Simulation Environment NCAS

NCAS, an interactive problem solving environment (PSE), visualizes and steers the simulation process. Via the interactive PSE, scientists and engineers can perform a discretization of basic equations, design and generate a simulation program, perform and steer computations, and visualize the simulation results in real time. NCAS also generates a domain-decomposition parallel program using MPI functions from a mathematical model. The steering and visualization capabilities are accomplished via a tree-type data structure for equations, symbols and processes. Utilizing the NCAS system, quick responses to the user’s steering are realized and potential errors are avoided.

A distributed problem solving environment (PSE) for scientific computing

A distributed problem solving environment (PSE) is proposed to help users solve partial differential equation (PDE) based problems in scientific computing. The system inputs a problem description and outputs a program flow, a C-language source code for the problem and also a document for the program. Each module is distributed on distributed computers. The PSE contains all the information of the problem, PDEs, discretization scheme, mesh information, equation manipulation results, designed program structure, variable and constant definitions and program itself. Therefore the documentation support module generates a document for the generated program and the problem itself in the PSE. The module liaison module generates an adapter module among the distributed PSE modules. The job execution service module deploys programs generated or prepared on distributed computer resources and helps users run the programs on the distributed computers. The concept of the distributed PSE extends the potential of conventional PSE systems

Mathematical Modeling Support in a Distributed Problem Solving Environment for Scientific Computing

In computing sciences (e-Sciences) we need computer power, excellent algorithms and programming power in order to solve scientific problems leading to discoveries and development of innovative new products. So far, the computer power and the computing algorithms have been developed incredibly, and have provided enormous contributions to e-Sciences and e-Productions. Problem solving environments (PSE) support the programming power in e-Sciences and e-Productions, and have been studied actively for a few decades. In this paper a distributed PSE, named D-NCAS is presented, and a computer-assisted mathematical modeling support is also discussed in D-NCAS, which helps users solve partial differential equation (PDE) based problems in scientific computing. The D-NCAS PSE inputs a problem description and outputs a program flow, a C-language source code for the problem and also a document for the program. Each PSE module is distributed on networklinked distributed computers. The PSE holds all the information of the problem: PDEs, discretization scheme, mesh information, equation manipulation results, designed program structure, variable and constant definitions and program itself. The PSE concept has been opening a new direction for the computer-assisted programming or development of scientific simulation programs or CAEs.

Scientific Simulation Execution Support on a Closed Distributed Computer Environment

It is difficult for users to submit jobs to distributed computers and to retrieve calculation data from them in scientific computings. In this paper, we discuss and develop a robust job execution service system in a closed distributed computer system. The job execution service system consists of a dynamic system management servers, execution servers and data servers. The dynamic system management server is duplicated in order to keep the system robust, and has an assistant management server. The dynamic system management server has a function of the job execution system management, including software deployment, program compilation, job execution, job status retrieval and computing data retrieval. This system does not require special middleware such as Globus or UNICORE or GLite or so. Users access the web page on the dynamic system management server, and the clients submit jobs. After the submitted job finishes, the dynamic system management server collects the information from other distributed computers. The dynamic management server and its assistant server move dynamically to new servers, if the present servers become busy. The dynamic system management server also demands the execution server to transfer the result data to the optimal data server. The dynamic system management server copies the computing data and sends the compressed computing data to another optimal data server in order for a robust data storage system. The clients can deploy their programs, execute jobs and retrieve the result data by accessing only the web page in the job execution service system. This job execution management server also has a function of automatic system construction, so that the users can manage the setup of the job execution management system easily on their closed distributed computers.

Design and Implementation of NAREGI Problem Solving Environment for Large-Scale Science Grid

NAREGI is a Japanese National Grid Project started in 2003, whose chief aim is to develop a set of Grid middleware to serve as a basis for future e- Science. In this paper, we describe a software tool called NAREGI-PSE (Problem Solving Environment), which aims to supports the scientists¿ works for scientific computer simulations on widely-distributed heterogeneous grid computing environment. Its core component is implemented as WSRF services based on some grid standards, such as Application Contents Service specification. NAREGI-PSE achieves functions sharing peculiar applications in each research community, which is implemented as Virtual Organization. The shared application program is easily compiled and deployed to grid environment using NAREGI-PSE.