• 한국항공운항학회지
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• 제24권1호
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• pp.33-40
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• 2016

ROK issued its first type certificate to the KC-100 airplane, Part 23 normal category, and become the State of Design (SoD) in 2013. Before this, ROK aviation regulations were focused on the operation and continued airworthiness of aircraft registered and operated in ROK that were designed and manufactured in another contracting state. Therefore the implementation of reporting system were restricted to gather the failure and service difficulty reports from the owners or operators and transmit the information to the State of Design and/or the manufacture relating to the type certificated aircraft. However, ROK, to fulfill the accountability of the State of Design, has to ensure there is a system to address the information received from the State of Registry on failure, malfunctions, defects and other occurrences that might cause adverse effects on the continuing airworthiness of the korean type certificated aircraft. This paper presents an overview of ICAO requirements for the State of Design, and current implementation of reporting system of USA and Japan and discusses the current status and further considerations on the rule-making for the malfunction, defect and failure reporting system applicable to the korean indigenous aircraft.

• 품질경영학회지
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• 제43권3호
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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.

• 한국산학기술학회논문지
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• 제17권8호
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• pp.379-388
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• 2016

현대 무기체계 제조를 위해 적용되는 수많은 생산 기술과 다양한 공정 환경으로 인해 다양한 결함이 무기체계 제조공정에 유입되고 있다. 이렇게 제조공정에 유입되는 결함 중 육안 검사, 기능 시험 등 기존 품질 관리 절차를 통해 검출할 수 있는 "명백결함(Patent Defect)"과 무기체계 복잡성과 제조공정의 복잡도로 기존 품질 관리 방식으로 검출이 제한되는 "잠재결함(Latent Defect)" 2가지 종류가 있다. 이러한 초기 결함 문제를 최소화하기 위해 무기체계 생산공정 중 유입된 결함요소를 환경부하(온도, 진동)를 활용하여 결함검출/제거/개선하기 위해 환경 부하 선별(ESS : Environmental Stress Screening) 시험을 수행해야 한다. 본 논문은 국내 무기체계 제조업체에서 정량적 환경 부하 선별 시험 설계의 어려움을 최소화하기 위해 MIL-HDBK-344(Environmental Stress Screening of Electronic Equipment)의 수학적 모델을 기반으로 정량적 환경 부하 선별시험 효과도 분석 및 프로파일 자동화 도구를 구현하였으며, 6가지(온도부하변수 3가지(온도범위/온도변화율/허용 잔류결함밀도), 진동부하변수 2가지(부하크기/허용 잔류결함밀도), 시험설계변수 1가지(허용 시험시간)) 시나리오를 통해 구현된 도구 유효성을 확인했다.

• 대한기관식도과학회지
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• 제11권1호
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• pp.32-36
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• 2005

This study aimed to report a case of infant who presented with a prenatal ultrasound diagnosis of agnathia, polyhydramnios followed by a review of previous studies. As widely acknowledge, agnathia is a complex lethal malformation characterized by absent mandible, microstomia, microglossia and ear anomaly which are secondary results to a defect of the first branchial auh. Newborn infants with agnathia often suffer from airway obstruction, causing fatal respiratory failure. The most difficult part of treating those newborns is to keep the airway patent. Therefore, as early airway management planning as possible is the most important part. Airway management was achieved with tracheotomy through an ex utero intrapartum treatment procedure(EXIT). The case of this infant, reporting here, was underwent tracheotomy with preservation of uteroplacental blood flow and gas exchange.

• Journal of Chest Surgery
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• 제29권4호
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• pp.440-443
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• 1996

삼첨 판막 심내막염은 감수성이 있는 항생제에 효과적으로 치료될 수 있다. 그러나 패혈증이 지속되거 나, 중증의 심부전, 다발성 폐 색전증 그리고 실 초음파상 증식증 (vegetation)이 있는 경우는 수술이 필요 하다. . 19세횝 남자환자가 감염성심내막염으로 입원하였다. 환자는 9년전에 perimembranous type의 VSD로 수술받은 병 력 이 있다. 심초음파상 삼첨판의 전엽부에 커다란 증식증의 소견이 보였고,과거에 VSD를 봉합했던 부위에 누 출 (leakage)을 통한 좌우단락이 관찰되었다. 항생제치료와 함께 인공판막치 환술을 시행하였다. St. Jude Medical 양엽판막 (size 33 mm으로 삼첨 판막 대 치술을 시 행하였고 잔여 VSD는 단순봉합으 로 폐쇄하였다. 술후 시행한 심초음파검사에서 치환된 삼첨 판막의 기능은 좋았고, 증식증과 좌우단락의 소견은 보이지 않았다. 환자는 합병증없이 술후 25일째에 퇴원하였다. 저자들이 경험한 본 증례는 잔여 VSD로 인해 생긴 감염성심내막염을 초기에 적극적인 수술을 시행 하여 좋은결과를 얻었음을 보여준다. 이 에 문헌고찰과 더불어 보고하는 바이다.

• Archives of Plastic Surgery
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• 제49권5호
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• pp.617-632
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• 2022

Tracheoesophageal puncture (TEP) and voice prosthesis insertion following laryngectomy may fail to form an adequate seal. When spontaneous closure of the fistula tract does not occur after conservative measures, surgical closure is required. The purpose of this study was to summarize the available evidence on surgical methods for TEP site closure. A comprehensive search across PubMed, Web of Science, SCOPUS, and Cochrane was performed to identify studies describing surgical techniques, outcomes, and complications for TEP closure. We evaluated the rate of unsuccessful TEP closure after surgical management. A meta-analysis with a random-effect method was performed. Thirty-four studies reporting on 144 patients satisfied inclusion criteria. The overall incidence of an unsuccessful TEP surgical closure was 6% (95% confidence interval [CI] 1-13%). Subgroup analysis showed an unsuccessful TEP closure rate for silicone button of 8% (95% CI < 1-43%), 7% (95% CI < 1-34%) for dermal graft interposition, < 1% (95% CI < 1-37%) for radial forearm free flap, < 1% (95% CI < 1-52%) for ligation of the fistula, 17% (95% CI < 1-64%) for interposition of a deltopectoral flap, 9% (95% CI < 1-28%) for primary closure, and 2% (95% CI < 1-20%) for interposition of a sternocleidomastoid muscle flap. Critical assessment of the reconstructive modality should take into consideration previous history of surgery or radiotherapy. Nonirradiated fields and small defects may benefit from fistula excision and tracheal and esophageal multilayer closure. In cases of previous radiotherapy, local flaps or free tissue transfer yield high successful TEP closure rates. Depending on the defect size, sternocleidomastoid muscle flap or fasciocutaneous free flaps are optimal alternatives.