• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.335-340
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• 2010

In this paper development of an automatic grid generation program for flow field calculation around 3D wing is described and its application is also introduced. The program is developed by using JAVA programming language and a graphic library, JOGL, and it can be usee either as an application program on a local computer or as a applet in the network environment. Currently, The program provides NACA series 4-digit airfoils as the wing cross-section shape and it offers a non-complicated GUI program which can easily generate structured grids for wings based on user's parameter input. Grid generated by the program can be selected as one of two types; O-type and C-type. In this research advancing layer method(ALM) augmented by elliptic smoothing method is used for the FLUENT. It is shown that by using current program high-quality structured grids around 3D wings can be easily generated, and typical grid generation results and flow solutions are demonstrated. Study on effects of geometric parameters on flow field is also tried by changing major wing parameters such as incidence angle type of wing-tip and sweepback angle.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.04a
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• pp.121-124
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• 2015

Recent global and cloud computing render the Internet and Web application to be a paramount field since it is uncomplicated to access and less time and space limitation. On the other hand, a growing number of computations using grid computing techniques indicates the requirements and quantities of large-scale computations are becoming foremost progressively. Therefore, that will be much practicable if there is a Web-based service that could provide Grid computing functions. In this paper, Several similar Web-based cloud and parallel computing systems will be discussed and a model of Web application termed GCaaS which supports grid computing services will be introduced.

• Journal of KIISE:Computer Systems and Theory
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• v.37 no.3
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• pp.127-137
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• 2010

As large-scale computational applications in various scientific domains have been utilized over many integrated sets of grid computing resources, the difficulty of their execution management and control has been increased. It is beneficial to refer job history generated from many application executions, in order to identify application‘s characteristics and to decide selection policies of grid resource meaningfully. In this paper, we apply a statistical technique, Plackett-Burman design with fold-over (PBDF), for analyzing grid environments and execution history of applications. PBDF design identifies main factors in grid environments and applications, ranks based on how much they affect to their execution time. The effective factors are used for selecting reference job profiles and then preferable resource based on the reference profiles is chosen. An application is performed on the selected resource and its execution result is added to job history. Factor's credit is adjusted according to the actual execution time. For a proof-of-concept, we analyzed job history from an aerospace research grid system to get characteristics of grid resource and applications. We built JARS algorithm and simulated the algorithm with the analyzed job history. The simulation result shows good reliability and considerable performance in grid environment with frequently crashed resources.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.240-243
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• 2010

Smart Phone supplies are diffused and substitute the Internet PC with Mobile communications which they are applied. Smart Phone in Smart Grid where electric power watch and the IT of existing amalgamate are used with business. Consequently from Smart Grid network connections which lead Smart Phone in about connection and control in about security vulnerabilities and Smart Grid networks the research is necessary in about vulnerability. It uses Smart Phone from the present paper and when approaching electric power watch systems which lead Smart Grid networks, it researches in about connection vulnerability. Also it uses Smart Phone and after connecting in Smart Grid networks a vulnerability in seizure possibility and, electric power information and control information, about private data etc. access authority it analyzes with the problem point which occurs it confronts it researches. And the research direction for a security reinforcement under presenting boil in about Smart Grid network security vulnerabilities which lead Smart Phone.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.12
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• pp.881-890
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• 2009

To solve big problem in high energy physics or bioinformatics, it needs a large number of computing resources. But it hard to be provided by one grid environment. While user can submit each job by using it's own user interface in each grid environment, it may need many cost and efforts to manage several hundred jobs conserved in each grid environment separately. In this paper, to solve this problem we develop Ganga's Gridway backend and InterGrid backend. Therefore as we provide the same grid user interface between different grid environments. We developed a Gridway backend module that provide users with access to globus-based grid resources as well. We have also developed an InterGrid backend that allows users to submit jobs that have access to both glite-based resources and globus-based resources. In order to demonstrate the practicality of the new backend plugin modules, we have integrated the AutoDock application used by WISDOM project into Ganga as a new built-in application plugin for Ganga. And we preformed interoperability experiment between PRAGMA grid based on Globus and EGEE grid based on gLite.

• Journal of Information Processing Systems
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• v.10 no.4
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• pp.491-502
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• 2014

In this paper we present some research results on computing intensive applications using modern high performance architectures and from the perspective of high computational needs. Computing intensive applications are an important family of applications in distributed computing domain. They have been object of study using different distributed computing paradigms and infrastructures. Such applications distinguish for their demanding needs for CPU computing, independently of the amount of data associated with the problem instance. Among computing intensive applications, there are applications based on simulations, aiming to maximize system resources for processing large computations for simulation. In this research work, we consider an application that simulates scheduling and resource allocation in a Grid computing system using Genetic Algorithms. In such application, a rather large number of simulations is needed to extract meaningful statistical results about the behavior of the simulation results. We study the performance of Oracle Grid Engine for such application running in a Cluster of high computing capacities. Several scenarios were generated to measure the response time and queuing time under different workloads and number of nodes in the cluster.

• Journal of Internet Computing and Services
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• v.13 no.6
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• pp.55-62
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• 2012

Grid web applications by standard Web technology are increasingly used to provide grid service to users as normal Web user interface and service. It is however difficult to integrate a grid security system such as Grid Security Infrastructure (GSI) into Web applications because the delegation way of standard Web security is not the same as the one of Grid security. This can be solved by allowing Web applications to get a Grid credential by using an online credential repository system such as MyProxy. In this paper, we investigate the problem that occurs when MyProxy, which assumes mutual trust between a user and Grid web application, is adapted for achieving security integration between Web and Grid, and we propose a new Grid proxy delegation service to delegate a Grid credential to the Web without assuming mutual trust. In the service, the X.509 proxy delegation process is added to OAuth protocol for credential exchange, and authentication can be done by an external service such as OpenID. So, users can login onto the Grid web application in a single sign-on manner, and are allowed to securely delegate and retrieve multiple credentials for one or more Virtual Organizations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.4
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• pp.785-794
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• 2009

We studied on a technic to improve and implement the virtual environment grid information in the war-game model. The virtual environment data are categorized into ground, sea, and air, and separatedly managed and operated. The data are implemented and managed in the geographical information and topography type information. The geographical information, including grid location coordinate and sea level, are managed in computer files as a grid type. We improved the representation of the sea level by mapping the sea level value of the grid information file into GCV and suggested the dynamic virtual environment implementation technic for the region with the large range of tide. In the experiments, we could know that it is possible to adopt the dynamic virtual environment to the war-game model.

• Journal of Information Processing Systems
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• v.7 no.2
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• pp.299-320
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• 2011

The overhead of processing fine-grain tasks on a grid induces the need for batch processing or task group deployment in order to minimise overall application turnaround time. When deciding the granularity of a batch, the processing requirements of each task should be considered as well as the utilisation constraints of the interconnecting network and the designated resources. However, the dynamic nature of a grid requires the batch size to be adaptable to the latest grid status. In this paper, we describe the policies and the specific techniques involved in the batch resizing process. We explain the nuts and bolts of these techniques in order to maximise the resulting benefits of batch processing. We conduct experiments to determine the nature of the policies and techniques in response to a real grid environment. The techniques are further investigated to highlight the important parameters for obtaining the appropriate task granularity for a grid resource.

• 한국전산유체공학회:학술대회논문집
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• 2005.04a
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• pp.47-50
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• 2005

The Grid'[1] means the collaboration of computing and experimental resources in dispersed organizations by high-speed network. It has been paid much attention for an unlimited number of potential resources available and the easiness to build collaborative environments among multiple disciplines. However, the difficulty in establishing the environments and accessing and utilizing the resources has prevented application scientists from conducting Grid computing. Thus, the present study focuses on building PSE(Problem Solving Environment) which assists application researchers to easily access and utilize the Grid. The Cactus toolkit, originally developed by astrophysicists, is used as a base frame for Grid PSE. Some modules are newly developed and modified for CFD(Computational Fluid Dynamics) analysis. Simultaneously, a web portal, Grid-One portal, is built for remote monitoring/control and job migration. Cactus frame through the web portal service has been applied to various CFD problems, demonstrating that the developed PSE is valuable for large-scaled applications on the Grid.