• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제2권1호
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• pp.27-34
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• 2013

클라우드 컴퓨팅 서비스에 대한 관심이 높아지고 있다. 하지만 많은 관심에도 불구하고 클라우드 컴퓨팅 서비스에 대한 기존 연구는 한계점이 있다. 선행연구들은 이 서비스가 제공하는 많은 혜택에 대한 연구와 이 서비스를 선택할 경우 발생할 수 있는 문제점에 대해 독립적으로 연구하고 있다. 하지만 실제 생활에서 소비자는 클라우드 컴퓨팅 서비스를 선택할 경우 혜택과 비용에 대해 동시에 고려한다. 따라서 본 연구에서는 클라우드 컴퓨팅 서비스 선택 시 혜택과 비용에 대한 상호작용 효과를 탐색적으로 분석하였다. 분석 결과 독립변수로써 유용성, 사회적영향, 그리고 혁신성은 인지된 가치에 모두 정(+)의 유의한 영향을 주었다. 하지만 혜택과 비용과의 상호작용 효과 분석 결과 유용성과 혁신성만이 비용과의 인지된 가치에 대해 통계학적으로 유의한 것으로 나타났다. 유용성은 비용과의 인지된 가치에 대해 상호작용 효과에 대해 음(-)의 결과가 나타났으며, 혁신성은 비용과의 인지된 가치에 대해 상호작용 효과 검정 결과 정(+)의 상호작용 효과가 있는 것으로 나타났다. 결국 본 연구는 클라우드 컴퓨팅 서비스를 선택할 경우 소비자가 느끼는 혜택의 경우 비용을 고려할 때 인지된 가치에 서로 다른 영향을 줄 수 있음을 실증했다는 점에서 의의가 있다고 하겠다.

• Journal of Mechanical Science and Technology
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• 제15권1호
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• pp.125-138
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• 2001

An efficient correction storage scheme on a structured grid is applied to a sequence of approximate Jacobian systems arising at each time step from a linearization of the discrete nonlenear system of equations, obtained by the implicit time discretization of the conservation laws for unsteady fluid flows. The contribution of freezing the Jacobian matrix to computing costs is investigated within the correction storage scheme. The performance of the procedure is exhibited by measuring CPU time required to obtain a fully developed laminar vortex shedding flow past a circular cylinder, and is compared with that of a collective iterative method on a single grid. In addition, some computed results of the flow are presented in terms of some functionals along with measured data. The computational test shows that the computing costs may be saved in favor of the correction storage scheme with the frozen Jacobian matrix, to a great extent.

• 산업경영시스템학회지
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• 제19권40호
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• pp.169-178
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• 1996

Geographically dispersed computing system is made of computers interconnected by a telecommunications network. To make the system operated efficiently, system designer must determine the allocation of data files to each node. In designing such distributed computing system, the most important issue is the determination of the numbers and the locations where database files are allocated. This is commonly referred to as the file allocation problem (FAP)[3]. The proposed model is a 0/l integer programming problem minimizing the sum of file storage costs and communication(query and update) costs. File allocation problem belongs to the class of NP-Complete problems. Because of the complexity, it is hard to solve. So, this paper presents an efficient heuristic algorithm to solve the file allocation problem using Tabu Search Technique. By comparing the optimal solutions with the heuristic solutions, it is believed that the proposed heuristic algorithm gives good solutions. Through the experimentation of various starting points and tabu restrictions, this paper presents fast and efficient method to solve the file allocation problem in the distributed computing system.

• International journal of advanced smart convergence
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• 제1권2호
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• pp.12-15
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• 2012

Energy costs for operating and cooling computing resources in Cloud infrastructure have increased significantly up to the point where they would surpass the hardware purchasing costs. Thus, reducing the energy consumption can save a significant amount of management cost. One of major approach is removing hardware over-provisioning. In this paper, we propose a technique that facilitates power saving through reducing resource over provisioning based on virtualization technology. To this end, we use dynamic workload shaping to reschedule and redistribute job requests considering overall power consumption. In this paper, we present our approach to shape workloads dynamically and distribute them on virtual machines and physical machines through virtualization technology. We generated synthetic workload data and evaluated it in simulating and real implementation. Our simulated results demonstrate our approach outperforms to when not using no workload shaping methodology.

• 한국정보과학회논문지:시스템및이론
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• 제26권10호
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• pp.1206-1216
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• 1999

이동 호스트란 시간과 공간의 제약 없이 필요한 기능을 수행하고, 또한 원하는 정보에 접근할 수 있는 휴대용 컴퓨터를 일컫는다. 이동 컴퓨팅 환경이란 이러한 이동 호스트들을 지원할 수 있도록 구성된 분산 환경이다. 따라서 이동 컴퓨팅 환경에서의 분산 알고리즘은 정적 호스트만을 고려한 기존의 분산 환경에서와는 다르게 이동 호스트의 여러 가지 특성들을 고려하여 제안되어야 한다. 즉, 이동 컴퓨팅 환경의 도래로 인하여 이동성과 휴대성, 그리고 무선 통신과 같은 특성들을 고려한 새로운 분산 상호 배제 알고리즘이 필요하다. 이제까지 이동 컴퓨팅 환경에서의 상호 배제 알고리즘은 토큰 링 구조에 기반을 두고 설계되었다. 토큰 링 구조는 이동 호스트들의 위치를 유지하기 위하여 높은 비용을 필요로 하는 단점을 가지고 있다. 본 논문에서는 균형 높이 트리(height-balanced tree)라는 새로운 모형을 제안함으로써 정적 분산 환경과 이동 분산 환경이 혼합된 환경에서 상호 배제 비용을 감소시킬 수 있는 새로운 알고리즘을 제안하며, 각 경우에 있어서의 비용을 산출하고 평가한다.Abstract The mobile host is a potable computer that carries out necessary functions and has the ability to access desirable informations without any constraints in time and space. Mobile computing environment is a distributed environment that is organized to support such mobile hosts. In that environment, distributed algorithms of which environment not only with static hosts but with mobile host's several properties should be proposed. With the emergence of mobile computing environments, a new distributed mutual exclusion method should be required to consider properties mobile computing system such as mobility, portability, and wireless communication. Until now, distributed mutual exclusion methods for mobile computing environments are designed based on a token ring structure, which have the drawbacks of requiring high costs in order to locate mobile hosts. In this paper, we propose a distributed mutual exclusion method that can reduce such costs by structuring the entire system as a height-balanced tree for static distributed networks and for networks with mobile hosts. We evaluated the operation costs in each case.

• 한국컴퓨터정보학회논문지
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• 제16권7호
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• pp.13-23
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• 2011

그리드 컴퓨팅은 지리적으로 분산된 이기종의 컴퓨팅 자원들을 상호 연결하고 공유하여 가상의 고성능 컴퓨팅시스템을 구성함으로서 대용량의 컴퓨팅 연산 등을 수행하는 차세대 컴퓨팅 기술이다. 이러한 그리드 컴퓨팅의 성능을 극대화하기 위해서는 효율적으로 작업을 자원에 할당하는 작업 스케줄링 기법이 필요하다. 따라서 작업 총 완료시간 등을 고려한 작업 스케줄링 기법에 대한 많은 연구가 진행되었다. 그러나 작업 스케줄링에 있어서 자원의 사용에 따른 자원 비용을 고려하는 것 역시 매우 중요하며, 자원 비용의 최소화를 통해 그리드 컴퓨팅의 전체적인 성능 및 경제적 효율성을 높일 수 있다. 따라서 본 논문에서는 시간과 비용을 모두 고려한 다목적 작업 스케줄링 모델을 제안한다. 제안하는 모델은 다목적 유전 알고리즘 기법의 하나인 NSGA-II를 적용하여 최적 해를 도출하였고, 모델의 효율성을 증명하기 위해 시뮬레이션 환경을 구성하여 기존의 스케줄링 모델인 Min-Min, Max-Min 알고리즘과의 비교 실험을 수행하였다. 이를 통해 제안한 스케줄링 모델이 기존 스케줄링 모델에 비해 작업 총 완료시간과 자원 비용을 더욱 효율적으로 최소화함을 증명하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권4호
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• pp.1520-1542
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• 2020

Traditional software testing typically uses many physical resources to manually build various test environments, resulting in high resource costs and long test time due to limited resources, especially for small enterprises. Cloud computing can provide sufficient low-cost virtual resources to alleviate these problems through the virtualization of physical resources. However, the provision of various test environments and services for implementing software testing rapidly and conveniently based on cloud computing is challenging. This paper proposes a multilayer cloud testing model based on cloud computing and implements a hybrid cloud testing system based on virtual machines (VMs) and networks. This system realizes the automatic and rapid creation of test environments and the remote use of test tools and test services. We conduct experiments on this system and evaluate its applicability in terms of the VM provision time, VM performance and virtual network performance. The experimental results demonstrate that the performance of the VMs and virtual networks is satisfactory and that this system can improve the test efficiency and reduce test costs through rapid virtual resource provision and convenient test services.

• 한국멀티미디어학회논문지
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• 제17권3호
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• pp.353-363
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• 2014

Cloud computing is an internet-based technology, providing services to the virtualized IT environment, and allowing users to add or remove resources of hardware or software at their discretion. Since Cloud computing can construct virtually integrated environments out of multiple local computing environments, various information services can be provided by it. In addition, state organizations also strive to build the cloud computing environments due to the benefits of reduced costs to introduce the system and of reduced time to build and provide the IT services. This study suggests a web-based cloud computing system for the computing environments, to be applied for the Korean National Health and Nutrition Examination Survey (KNHANES) by the Ministry of Health and Welfare, Republic of Korea.

• 한국BIM학회 논문집
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• 제6권3호
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• pp.49-56
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• 2016

As project opportunities for the Architecture, Engineering and Construction (AEC) industry have grown more complex and larger, the utilization of Building Information Modeling (BIM) technologies for three-dimensional (3D) design and simulation practices has been increasing significantly; the typical applications of the BIM technologies include clash detection and design alternative based on 3D planning, which have been expanded over to the technology of construction management in the AEC industry for virtual design and construction. As for now, commercial BIM software has been operated under a single-user environment, which is why initial costs for its introduction are very high. Cloud computing, one of the most promising next-generation Internet technologies, enables simple Internet devices to use services and resources provided with BIM software. Recently in Korea, studies to link between BIM and cloud computing technologies have been directed toward saving costs to build BIM-related infrastructure, and providing various BIM services for small- and medium-sized enterprises (SMEs). This study addressed development of the usage metering functions of BIM software under cloud computing architecture in order to archive and use BIM data and create an optimal revenue structure so that the BIM services may grow spontaneously, considering a demand for cloud resources. For the reason, we surveyed relevant cases, and then analyzed needs and requirements from AEC industry. Based on the relevant cases, customizing for cloud BIM and design for the development was performed. We also surveyed any related-law to support cloud computing-based BIM service. Finally, we proposed herein how to optimally design and develop the usage metering functions of cloud BIM software.

• 산업경영시스템학회지
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• 제18권35호
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• pp.17-24
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• 1995

The classification of quality costs by item is essencial to sum up the entire quality cost but the reality of classifying the quality cost by the firm is facing with difficulty in terms of grouping the concerned items. Meanwhile, the classification of items and calculating method of quality costs should be prepared in adcance with a certain standards and or regulations to figure out the accurate quality costs successfuly. This case study provides the contents of quality costs calulated by item and the method of calculation in detail which is applicable to automobile component industry md, also introduce how to set up the computing system of quality costs.