• Journal of Industrial Technology
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• v.29 no.A
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• pp.27-36
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• 2009

Reliability plays a pivotal role in products safety and quality. DoD RIAC recently developed a new reliability prediction methodology, $217Plus^{TM}$, for electronic systems. It officially replaces the well-known MIL-HDBK-217 and is expected to be widely used. Although theoretic study about $217Plus^{TM}$ and its application towards field systems seem to be attractive, it is also desirable to understand the general background of its development. In this paper, we performed a historical review of the arenas related to reliability prediction. Due to the vast of materials, our scope was limited to the development of $217Plus^{TM}$. We first reviewed Rome Laboratory and RIAC. We then explained the development course of reliability methods, MIL-HDBK-217, PRISM, and 217-Plus. This review will form not only a good understanding of the methodology but a basis for future study. We conclude this study with provision of future research areas.

• Journal of Industrial Technology
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• v.29 no.A
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• pp.37-46
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• 2009

As the level of technology and the standard of living improve, product reliability plays an increasingly significant role. This study has been performed to build a reliability model of electronic ballasts for the low wattage fluorescent lamp. Telcordia SR-332, one of the most widely used reliability specifications, was selected for the model development. We briefly reviewed the basic concepts of the electronic ballast. We then developed a reliability model for the ballast using SR-332 concepts and the reliability has been examined. We further discussed the significance of the first-year failure effect on the mean life.

• Journal of Industrial Technology
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• v.25 no.A
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• pp.105-113
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• 2005

A business process flow model for an intermediary type shopping mall consisting of multiple sellers has been presented in this study. Specifically, we defined 11 essential business processes of a front office customer's view point and set up detailed process flow models using IDEF3 (Integrated DEFinition). The characteristic of this study lies in providing a dynamic model rather than static models. The results may form a conceptual framework not only for shopping mall processes but for analysis and improvement toward extended electronic business systems.

• Journal of Industrial Technology
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• v.25 no.A
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• pp.115-122
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• 2005

A business process flow model for an intermediary type shopping mall consisting of multiple sellers has been presented in this study. Specifically, we defined 7 essential business processes of the shopping mall administrator and 6 processes of the administrator of a seller. We then performed detailed process flow models using IDEF3 (Integrated DEFinition). The characteristic of this study lies in providing a dynamic model rather than static models. The results may form a conceptual framework not only for shopping mall processes but for analysis and improvement toward extended electronic business systems.

• Journal of Industrial Technology
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• v.25 no.A
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• pp.123-131
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• 2005

Semantic object model has widely been recognized as an alternative data modeling approach to entity-relationship model for database system design. In this study, we have presented a semantic object model for intermediary type shopping mall consisting of multiple buyers and sellers. Essential processes and information with regard to the customer management, product management, price estimation, product order etc. have been considered for this study. Upon careful examination and analysis of them, a detailed semantic objects and attributes have been drawn and structured into semantic object diagrams. The final objects were converted into an entity-relationship diagram so that intuitive comparison could be made for relational database design. The results in this study may form a conceptual framework for both academic concerns and more complicated system applications.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.245-248
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• 2008

In this paper, we are studied on the electrical safety of panel board based on FMEA in dust generation area. For the safely of electrical facilities, the assessments of panel board are very important in dust generation area. Through the assessments of panel board and recommendations of electrical safety, there are expected that will be helped the judgement of electrical facilities.

• Journal of Industrial Technology
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• v.27 no.B
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• pp.245-253
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• 2007

Failure rate serves as a pivotal role in reliability study. Of all, the constant failure rate is the most popularly used in field exercises. In reality, however, the electrical and electronic parts' life is represented by not only the constant failure rate but the decreasing and/or increasing failure rates. Explicit consideration and incorporation of them into the model development may yield more desirable results. In this study, we built a reliability model for failure rates varying over time intervals and derived well known measures such as probability density function, reliability function, mean life, moments, and mission time. We then evaluated mean life with consideration of the first-year multiplier and compared the results those with constant failure rate. The results given in the study may provide a reference applying for practical decision making.

• Journal of Industrial Technology
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• v.27 no.B
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• pp.255-261
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• 2007

Product reliability plays a significantly important role these days. This study has been performed to examine the widely being used specifications, MIL-HDBK-217 and SR-332 for electronic parts. We specifically selected an electronic ballast of the low wattage fluorescent lamp for the study. We briefly reviewed the reliability specifications with the basic concepts of the ballast. We then valuated failure rates of the parts using MIL-HDBK-217 and SR-332 specifications. Since the quality and environment factor values are subjectively determined for failure rate evaluations, we excluded them for comparison.

• Journal of Industrial Technology
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• v.31 no.A
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• pp.3-9
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• 2011

Simulation plays an important role for system analysis. In this study, a manufacturing system has been analyzed through computer simulation. We first briefly explain the considered system with prevailing problems. We then build a simulation model using ARENA simulation language. Based on two selected performance measures, material transporter load and hourly throughput, explicit system analyses have been performed. We addressed four parameters - variation of the processing time, number of raw material transporters, quality failure rate, and machine failures - as the input parameters affecting the output measures selected. We adopted Taguchi's orthogonal array in statistical experimental design and drew meaningful results from the analysis. The results given in the study may provide a good guidance for practical applications.

• Journal of Industrial Technology
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• v.31 no.A
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• pp.11-19
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• 2011

A new PCD (Pitch Circle Diameter) adjustment system has been designed in this study. Traditional system requires repetitive same works in changing automobile tires. The system proposed in this study requires just one simultaneous work to finish the job. We designed the system using Solidworks CAD software. We further investigate the jobs for both cases through work factor method. Based on careful clarification of the job, work factor units were assigned to each work factor. Even if further analysis should be processed for actual field application, the mechanism proposed in this study may provide good reference for practical usage.