• Journal of KIISE:Computer Systems and Theory
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• v.33 no.7
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• pp.429-439
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• 2006

A desktop grid, which is a computing grid composed of idle computing resources in a large network of desktop computers, is a promising platform for compute-intensive distributed computing applications. However, due to reliability and unpredictability of computing resources, effective scheduling of parallel computing applications on such a platform is a difficult problem. This paper proposes a new scheduling method aimed at reducing the total execution time of a parallel application on a desktop grid. The proposed method is based on utilizing the histories of execution behavior of individual computing nodes in the scheduling algorithm. In order to test out the feasibility of this idea, execution trace data were collected from a set of 40 desktop workstations over a period of seven weeks. Then, based on this data, the execution of several representative parallel applications were simulated using trace-driven simulation. The simulation results showed that the proposed method improves the execution time of the target applications significantly when compared to previous desktop grid scheduling methods. In addition, there were fewer instances of application suspension and failure.

• Journal of KIISE:Computer Systems and Theory
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• v.37 no.3
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• pp.147-160
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• 2010

The system virtualization shows interest in the consolidation of servers for the efficient utilization of system resources. There are many various researches to utilize a server machine more efficiently through the system virtualization technique, and improve performance of the virtualization software. These researches have studied with the activity to control the resource allocation of virtual machines dynamically focused on CPU, or to manage resources in the cross-machine using the migration. However, the researches of the memory management have been wholly lacking. In this respect, the use of memory is limited to allocate the memory statically to virtual machine in server consolidation. Unfortunately, the static allocation of the memory causes a great quantity of the idle memory and decreases the memory utilization. The underutilization of the memory makes other side effects such as the load of other system resources or the performance degradation of services in virtual machines. In this paper, we suggest the dynamic allocation of the memory in Xen to control the memory allocation of virtual machines for the utilization without the performance degradation. Using AR model for the prediction of the memory usage and ACO (Ant Colony Optimization) algorithm for optimizing the memory utilization, the system operates more virtual machines without the performance degradation of servers. Accordingly, we have obtained 1.4 times better utilization than the static allocation.

• Journal of Digital Contents Society
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• v.17 no.1
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• pp.51-57
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• 2016

Distributed Computing attempts to harness a massive computing power using a great numbers of idle PCs resource distributed linked to the internet and processes a variety of applications parallel way such as bio, climate, cryptology, and astronomy. In this paper, we develop internet-distributed computing environment, so that we can analyze High Resolution Rainfall Prediction application in meteorological field. For analyze the rainfall forecast in Korea peninsula, we used QPM(Quantitative Precipitation Model) that is a mesoscale forecasting model. It needs to a lot of time to construct model which consisted of 27KM grid spacing, also the efficiency is degraded. On the other hand, based on this model it is easy to understand the distribution of rainfall calculated in accordance with the detailed topography of the area represented by a small terrain model reflecting the effects 3km radius of detail and terrain can improve the computational efficiency. The model is broken down into detailed area greater the required parallelism and increases the number of compute nodes that efficiency is increased linearly.. This model is distributed divided in two sub-grid distributed units of work to be done in the domain of $20{\times}20$ is networked computing resources.

• Journal of Convergence for Information Technology
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• v.10 no.11
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• pp.302-312
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• 2020

This study examined whether there is a difference in cost asymmetry between a corporate listed on KOSDAQ and a corporate listed on KOSPI, and whether there is a difference in cost asymmetry depending on the size of the listed corporate. In the previous study, cost asymmetry was examined only for listed corporate, but the difference in size between KOSDAQ-listed corporate and KOSPI-listed corporate was not examined. However, according to many studies, since the characteristics of corporate and firm risks are different between corporate listed on KOSPI and corporate listed on KOSDAQ, or even for listed corporate, such an impact may affect the decision-making of internal resource allocation. The analysis was conducted that there would be a difference in the impact. For this study, the results of analyzing the KOSPI and KOSDAQ markets from 2011 to 2019 using the cost behavior model of Anderson et al. (2003), There was a difference in cost behavior in the KOSPI and KOSDAQ markets. Overall, as in previous studies, Cost Stickiness was appeared. but in the case of the KOSPI market, Cost Stickiness was mitigated.It was found that corporate with large corporate size made the decision to dispose of idle resources more clearly when sales decreased. In addition, it was observed that the higher the foreign investor's ownership ratio, the KOSPI market, and the larger the corporate size, the more clearly the Stickiness of cost was mitigated. This study expands research on cost asymmetry and reveals that there is a difference between the KOSPI market and the KOSDAQ market, and between the size of the corporate, and has a differentiation from previous studies.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.455-458
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• 2013

The conventional design of the information system architecture based on the personal experience of information systems has been acted as a limit in progress utilizing appropriate resource allocation and performance improvements. Architecture design depending on personal experience makes differences in variance of a designer's experience, intellectual level in related tasks and surroundings, and architecture quality according to individual's propensity. After all these problems cause a waste of expensive hardware resources. At working place, post-monitoring tools are diversely developed and are running to find the bottleneck and the process problems in the information operation. However, there are no simulation tools or models that are used for expecting and counteracting the problems at early period of designing architecture. To solve these problems we will first develop a simulation model for designing information system architecture in a pilot form, and will verify validity. If an error rate is found in the permissible range, then it can be said that the simulation reflects the characteristic of information system architecture. After the model is developed in a level that can be used in various ways, more accurate performance computation will be able to do, getting out of the old way relying on calculations, and prevent the existence of idle resources and expense waste that comes from the wrong design of architecture.