• Culinary science and hospitality research
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• v.13 no.4
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• pp.107-118
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• 2007

This research aimed to understand the relationship between comparative superiority elements of the supply chain activities for food supplies in the hotel industry. The samples are obtained from exclusive hotels located in the Seoul area. A statistic package program called SPSS was employed to conduct reliability analysis, factor analysis, t-test, correlation analysis, and multiple regression analysis. Results of a multiple regression analysis between supply chain management and food production strategies were as follows; company's characters and cooperative relations with suppliers had a significant impact on cost while quality was significantly affected by company's characters, information system, cooperative relations with suppliers, and supply chain activities. It was revealed that all factors had a significant impact on flexibility and delivery date.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.439-449
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• 2002

This paper reviews our recent research works on the interconnection technologies in electronic packaging and assembly. At the aspect of advanced joining methods, laser-ultrasonic fluxless soldering technology was proposed. The characteristic of this technology is that the oxide film was removed through the vibration excitated by high frequency laser change in the molten solder droplet. Application researches of laser soldering technology on solder bumping of BGA packages were carried out. Furthermore, interfacial reaction between SnPb eutectic solder and Au/Ni/Cu pad during laser reflow was analyzed. At the aspect of soldered joints' reliability, the system for predicting and analyzing SMT solder joint shape and reliability(PSAR) has been designed. Optimization design method of soldered joints' structure was brought forward after the investigation of fatigue failure of RC chip devices and BGA packages under temperature cyclic conditions with FEM analysis and experimental study. At the aspect of solder alloy design, alloy design method based on quantum was proposed. The macroproperties such as melting point, wettability and strength were described by the electron parameters. In this way, a great deal of the experimental investigations was replaced, so as to realize the design and research of any kinds of solder alloys with low cost and high efficiency.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.40 no.2
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• pp.26-37
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• 2003

An optimal software release, which is related to the development cost, error detection and correction under the various operation systems, is a critical factor for managing project. This paper described optimal software release issues to predict the release time of large switching system with the system stability point of view and evaluated a timely supply of target system, proper utilization of resources under the software reliability valuation basis. Finally, Using initial failure data, based on the exponential reliability growth model methodology, optimal release time, and analysis of failure data during the system testing and managing methodologies were presented.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.6
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• pp.290-295
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• 2002

The present assignment in installing the number of switches for distribution line was made on the basis of a normal feeder capacity 7,000kVA in KEPCO(Korea Electric Power Corporation), Korea. But the normal capacity is revised to 10000kVA in 1998. Even increasing limit of the operating capacity of the distribution lines enables us to give some benefit for the operation flexibility and investment cost of the distribution system. It is disadvantageous in the viewpoint of supply reliability. In distribution systems, switches are equipped to improve the reliability of distribution systems by minimizing the outage section due to fault and maintenance. Utility generally improves the reliability by minimizing the length of outage section, which is caused by fault and maintenance, through switch equipment on distribution system. In order to cope with the changes such as operation capacity, it is necessary to study whether the present criteria is reasonable or not, also to confirm whether the present criteria of installing switches in line is improved or not. In this study, we proposes the number of switch per feeder on the basis of present operation capacity in distribution system.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.7
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• pp.18-27
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• 2006

The conventional reliability based design optimization(RBDO) methods require high computational cost compared with the deterministic design optimization(DO) methods, therefore it is hard to apply directly to large-scaled problems such as an aerodynamic shape design optimization. In this study, to overcome this computational limitation the efficient RBDO procedure with the two-point approximation(TPA) and adjoint sensitivity analysis is proposed, that the computational requirement is nearly the same as DO and the reliability accuracy is good compared with that of RBDO. Using this, the 3-D aerodynamic shape design optimization is performed very efficiently.

• The Korean Journal of Health Service Management
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• v.7 no.4
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• pp.273-288
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• 2013

This paper is a general review contextualizing the state of the domestic health technology assessment. The aim of the paper is to present an overview of health technology assessment in Korea based on examining clinical efficacy as well as cost-benefit analysis, and to suggest the issue of appraisal based on social value. We have included a discussion of a major case study of the technology appraisal process of NICE (the National Institute for Clinical Excellence) in the UK. The review of the existing process of NICE shows that the appraisal both gives interest in health technology a sense of value perspective and raises methodological issues in terms of reliability. Details of the appraisal process and several guidelines for best practice have emerged. Suggestions are listed and their role in assessing is explained as a conclusion.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.1
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• pp.58-65
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• 2008

Reliability-Centered Maintenance plan for maintenance schedule of generating unit is being assessed in this paper. Maintenance schedule is a key index that can be used to determine stability and cost. In this paper, stochastic FMECA is described for the life assessment by using probability distribution, and combustion-turbine generations in Korean power systems have been assessed for maintenance schedule. Such an assessment can be a useful guide for maintenance plans in restructured power industry.

• The Transactions of the Korea Information Processing Society
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• v.6 no.12
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• pp.3662-3674
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• 1999

This paper addresses some design issues for establishing the optimal number of spare units in array systems manufactured using fault-tolerant multichip modules(MCM's) for massively parallel computing(MPC). We propose a new quantitative approach to an optimal cost-effective MCM system design under yield and reliability constraints. In the proposed approach, we analyze the effect of residual redundancy on operational reliability of fault-tolerant MCM's. In particular, the issues of imperfect support circuitry, chip assembly yield and array topology are investigated. Extensive parametric results for the analysis are provided to show that our scheme can be applied to design ways using MCM's for MPC applications more efficiently, subject to yield and reliability constraints.

• Journal of Korea Society of Digital Industry and Information Management
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• v.17 no.1
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• pp.25-34
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• 2021

Availability is one of the important factor for developing weapon system, because it indicates the mission capability and sustainable life cycle management of weapon system. Recently, as weapon system becomes more advanced and more complex, availability estimation becomes more important to reduce the life cycle cost of weapon system. Modeling and simulation(M&S) is useful method to describe the availability of complex weapon system applying operational environment and maintenance plan. Especially agent based model(ABM) has the strength to describe interactions between agents and environments in complex system. Therefore, this paper presents the availability estimation of weapon system using agent based model. The sample data of part list and reliability analysis is applied to build availability estimation model. User agent and mechanic agent are developed to illustrate the behavior of operation and maintenance using formal specification. Storage reliability is applied to describe failure of each parts. The experimental result shows that this model is quite useful to estimate availability of weapon system. This model may estimate more reasonable availability, if full scale data of weapon system and real field data of operation is provided.

• Convergence Security Journal
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• v.15 no.5
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• pp.9-15
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• 2015

Cloud computing has emerged with promise to decrease the cost of server additional cost and expanding the data storage and ease for computer resource sharing and apply the new technologies. However, Cloud computing also raises many new security concerns due to the new structure of the cloud service models. Therefore, several cloud service certification system were performed in the world in order to meet customers need which is the safe and reliable cloud service. This paper we propose the new risk analysis method different compare with existing method for secure the reliability of certification considering public IaaS(Infrastructure as a Service) cloud service properties.