• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.243-243
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• 2017

• Journal of Korean Society for Quality Management
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• v.43 no.3
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• pp.273-288
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• 2015

Purpose: In this study, we apply environmental stress screening (ESS) to battle management system (BMS) of a tank and use the ESS profile based on production process data, guided by MIL-HDBK-781/344/2164. Methods: To optimize ESS Profile of the BMS of a tank, we estimate ESS model parameters (e.g., defect density, screening strength) using primary production failure reporting and corrective action system (FRACAS) data of military supply contract firm. Results: First, we collect the Primary production FRACAS data of military supply contract firm. Second, we compute curve fitting approach to find patent defect density and latent defect density using FRACAS data. Third, we solve the equation of Defect Density(patent defect density + latent defect density)($D_{IN}$) and Screening Strength(SS) Using second step data. As a result of analysis according to the order, we calculate $D_{IN}$(Temperature stress case : 74.02, Vibration stress : 10.252) and : SS(Temperature stress case : 0.4632, Vibration stress : 0.4142) and confirm the Condition II-D based on MIL-HDBK-344. According to Condition II-D, it is necessary to modify existing ESS profile through decreasing the $D_{IN}$ and increasing the SS. Conclusion: Identification of defect causes through ESS approach reduce defect densities for production. It provides feedback to a lessons-learned data base to avoid similar problems on next generation tank BMS.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.379-388
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• 2016

There are various system defects from weapons manufacturing due to the numerous production processes and various production environments. The first kind of defect is patent defects, which can be detected by visual inspection, functional testing, and existing quality control procedures during the manufacturing process. The second kind is latent defects, which cannot be detected though existing quality management approaches because of the complexity of the system and manufacturing process. To minimize the initial defect problems, environmental stress screening (ESS) is needed to detect the defects, remove them, and improve the product conditions based on the environmental stress conditions of temperature and vibration. We implemented a tool for quantitative ESS effectiveness analysis and profile design automation based on MIL-HDBK-344 and verified it using six scenarios with different temperature stress, vibration stress, and test designs.

• Solar Energy
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• v.20 no.3
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• pp.1-9
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• 2000

In these days the hot water circulating Ondol using the fossil fuel boiler is the heating system for the most of the Korean residents. Then it is installed without the heat storage medium in the Ondol heating layer, but the Korean traditional Ondol had been composed with the heat storage medium. The Ondol room without heat storage medium could not be comfortable because the room air temperature is not only changed unstably but also it has a defect too much fuel consumption. Therefore in this study the heat pump-latent heat storage Ondol as the new type of Ondol system was developed to solve these problems mentioned above, and the COP of the heat pump (Coefficient Of Performance), the latent heat storage characteristics in the new type of Ondol system and the temperature variation in the Ondol room with the ambient temperature were analyzed.

• Electronics and Telecommunications Trends
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• v.18 no.2 s.80
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• pp.99-109
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• 2003

검출된 소프트웨어의 결함에 대한 분석은 소프트웨어의 품질을 향상시키기 위한 여러 활동에 많은 도움을 주고 있다. 특히 개발중인 소프트웨어 컴포넌트들에 대한 검출된 결함 분석은 개발기간에 소프트웨어내에 숨어있는 결함(latent defect)에 초점이 맞추어져 시험에 많은 도움을 주고 있다. 본 논문은 대형 교환 소프트웨어로부터 시험에서 검출된 결함 데이터를 이용하여 소프트웨어의 특성을 조사, 분석하여 이를 시험에 활용하고 시험의 효율성과 시험효과에 대한 가이드 라인을 제안한다.

• Journal of the Korea Society of Computer and Information
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• v.17 no.6
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• pp.101-109
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• 2012

To develop high quality software, quality control plan is required about fault correction that is latent within software. We should describe fault correction profile properly for this. The tank and pipe model performs complex processes to calculate fault that is remove and escapes. Also, we have to know in which phase the faults were inserted, removed and escaped and know the fault detection rate at any phases. To simplify such complex process, this paper presented model to fault filtering concept. Presented model has advantage that can describe fault more shortly because need not to consider whether was involved in fault that escaped fault is inserted at any step at free step. Also, presented effort estimating model that do fetters in function of fault removal quality and productivity measure and is required in fault detection.

• Journal of the Korea Furniture Society
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• v.21 no.4
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• pp.314-325
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• 2010

Shake and gnarl in the timber market are considered as a defect of reducing the quality of timber. However, this study expects that shake and gnarl are the optimum design tools to improve aesthetics of furniture if their unique form is properly used as formative expression factors of wooden furniture. This study is conducted to suggest methods in order for consumers and designers to consider shake and gnarl as new formative factors and apply them to wooden furniture designs. The study conducts a preference survey of general people by manufacturing furniture that has or doesn't have shake and gnarl, and measures the level of aesthetics after providing furniture design majors with furniture image that reprocesses shake and gnarl in a new way. According to the findings, shake and gnarl have latent aesthetic values, which verifies that various methods can be used to improve aesthetics of wooden furniture by means of a case study. By applying hidden authentic value of the verified shake and gnarl to furniture design, various improvement methods of aesthetics will have to be actively studied.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.4
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• pp.325-329
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• 2009

Objective : This is to report the effectiveness of intraoral distraction osteogenesis, iliac bone graft for alveolar augmentation in the extremely atrophied alveolar defects after infected allobone grafted area. Subjects and Methods : Anterior segmental osteotomy was performed and the trans-oral alveolar distractors (Martin, Germany) were applied in patient with the severe acquired anterior mandibular and mandibular defect after ameloblastoma enucleation. Iliac bone grafts were performed in defect sites and distraction osteogenesis were treated. After latent period for 1 week, the osteomized alveolar segments were distracted by 0.75 mm a day (0.25 mm/1 turn) for 10 days The consolidation period was about 12 weeks. Thereafter, 2 titanium threaded implants were simultaneously installed with removal of distractor. For oral rehabilitiation, The implants were installed in maxilla, mandible. It was tested with clinically and radiographically. Results : Amounts of acquired alveolar bone were 10 mm with the increased width of the ridge crests and soft tissue expansion. Dental implants installated on the augmented alveolar ridges in 12 weeks after distraction were confirmed as in good osseointegration and in good function without any complications. Conclusion : Intraoral distraction osteogenesis can be a good option for alveolar ridge augmentation of the severely atrophied ridges and soft-tissue defects.

• International Journal of Automotive Technology
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• v.7 no.6
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• pp.741-747
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• 2006

It has been almost impossible to predict the fatigue life in the field of rubber materials by numerical methods. One of the reasons is that there are no obvious fracture criteria and excessively various ways of mixing processes. Tearing energy is considered as a fracture criterion which can be applied to rubber compounds regardless of different types of fillers, relative to other fracture factors. Fatigue life of rubber materials can be approximately predicted based on the assumption that the latent defect caused by contaminants or voids in the matrix, imperfectly dispersed compounding ingredients, mold lubricants and surface flaws always exists. Numerical expression for the prediction of fatigue life was derived from the rate of rough cut growth region and the formulated tearing energy equation. Endurance test data for dumbbell specimens were compared with the predicted fatigue life for verification. Also, fatigue life of industrial rubber components was predicted.

• Proceedings of the Korean Society for Quality Management Conference
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• 2006.04a
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• pp.381-391
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• 2006

When the environmental materials of the raw and sub material to applied in electronic goods removed, the reliability assessment and the forecasting is stand on the low level and in case of neglect, it is acting as latent defect that can be connected to large size disaster. In this research, the study on the management method of environmental restriction substances which is recognized as important element in the reliability assessment about environmental material of electronic goods and the study on reliability assessment method of PWB without environmental material are progressed