• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2010년도 춘계학술대회 논문집
• /
• pp.2215-2222
• /
• 2010

Advanced EMU have been enhanced in terms of safe transport and maintainability. It is a new urban railway technology that enables an operation institution to cut repair and maintenance costs and customers to use convenient service at lower costs based on IT technology. If a development vehicle of Advanced EMU is completed, it will be used to test the entire advanced EMU system through sufficient performance check and reliability check prior to operation in commercial line. It will also verify efficiency, safety, punctuality and energy efficiency of transport. Accordingly, it is necessary to figure how to repair and maintain vehicles to enhance safety of Advanced EMU system in cooperation with operation during the period of comprehensive evaluation on the operation of a development vehicle in a test line. In this paper, we investigated the maintenance program of Advanced EMU on test operation in Dabul line. The test condition and operation environment of Advanced EMU in Daebul line was analyzed.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2013년도 추계 학술논문 발표대회
• /
• pp.114-115
• /
• 2013

The maintenance and repair period consists the largest part of a construction project life cycle cost. However, it has been analyzed that the repairing plan relies on regulations and the officers' experience mostly that sometimes lead to performing unnecessary work. Moreover, the data occurred during repairing have not been stored in a system that can be used in future plans. Therefore, the purpose of this study is to suggest a repairing cost and time predicting model by applying the properties of the building.

• 대한방사선치료학회지
• /
• 제23권2호
• /
• pp.83-90
• /
• 2011

목 적: 일정한 호흡주기의 유지가 필요한 방사선치료에서 치료 자세와 device의 사용에 따른 호흡주기의 차이를 통계적으로 분석하여, 그 경향과 device의 유용성에 관하여 알아보고자 한다. 대상 및 방법: 피험자 11명을 대상으로 바로 누운 자세와 엎드린 자세에서 각 20분씩 호흡주기를 유지한 호흡신호를 획득 및 분석하였다. 엎드린 자세에서 호흡주기의 유지가 양호하지 못한 7명에게 belly board를 사용한 후 호흡신호를 획득하여 device의 사용전후의 호흡변화와 안정성을 분석하였다(통계 분석에는 PASW 18.0을 이용). 결 과: 피험자의 특성에 따른 차이는 없었으며 자세에 따른 호흡주기유지 안정성은 바로 누운 자세 54.5%, 엎드린 자세 36.4%로 나타났다. Belly board를 사용한 7명 중 4명은 호흡주기유지 안정성이 유의하게 양호한 변화를 보였으며, 허리치수에 따라 바로 누운 자세에서 처음 10분간의 호흡주기유지에는 유의한 차이(P=0.022, Fisher's Exact Test)를 보였다. 시간의 흐름에 따른 호흡의 안정성은 7명(63%)이 엎드린 자세보다 바로 누운 자세에서 보다 안정적이었다. 결 론: 흉부 및 복부 심지어 골반의 방사선치료에서도 호흡에 의한 환자의 움직임은 중요한 고려사항 중 하나이다. 본 연구와 같이 호흡신호의 통계적 분석과 이의 적용을 통해 호흡유지에 최적의 자세, belly board와 같은 device 사용여부를 결정하면 호흡주기의 유지 및 호흡의 안정도 유지에 기여할 수 있을 것으로 사료된다.

• 유통과학연구
• /
• 제11권4호
• /
• pp.23-35
• /
• 2013

Purpose - This paper attempts to identify the problems and limitations of a market maintenance project conducted according to the 「Special Act for the Development of Traditional Markets and Shopping Street」 and to present a revised direction for the special law and lay the groundwork for market maintenance projects to be promoted smoothly. Research design, data, and methodology - The revised direction for the legislation and the proposal were written based on an investigation of the problems and the legal system, and proposed measures for market maintenance operation and system improvements to derive the improvements needed for market maintenance projects. Results - A market maintenance project has been conducted as a means to reinvigorate traditional markets that are economically depressed, and to revive the local economy. It was largely conducted in the form of reconstruction and redevelopment and represents the interests of landowners and merchants. Thus, it is most likely to contribute to the gradual disappearance of traditional markets. First, as part of a market maintenance project, many companies are building multipurpose buildings or high-rise residential buildings to increase profits. In these high-rise buildings, they can raise rents, which may not be affordable for some existing small businesses. To solve such problems, the large-scale store registration requirement needs to be relaxed or abolished once the market maintenance project is completed. If the large-scale store registration requirement is to be abolished, the term 'large retail store' should be changed in the 「Special Act for the Development of Traditional Markets and Shopping Street」. After registration, the Small and Medium Business Administration should train merchants, offer consultations, and support events, to the extent that the existing traditional market management modernization project permits, and further continue to manage and support its ongoing activities. However, unless large-scale store registration is abolished, adding an exception clause in the special law to relax large-scale store registration criteria, and permitting changes to building use is another option. At the end of a market maintenance project, empty stores should be purchased by the Small and Medium Business Administration, and local government, etc., at the actual construction cost, to utilize them as public rental shopping areas, which in turn may be re-utilized as a temporary market for another market maintenance project. The second problem in market maintenance projects is merchant-protection. Currently, the special law prescribes that a temporary market be created for merchants to conduct business during the rental period of a market maintenance project. Conclusions - In reality, a market maintenance project is conducted usually in big metropolitan cities with 500,000 residents or more. The main building type created under these projects is a multipurpose building. For this reason, it is very difficult to secure a location for a temporary market in the surrounding area of such a project. To solve this problem, this study suggests 'public rental shopping areas' as mentioned above.

• 한국재난정보학회 논문집
• /
• 제16권1호
• /
• pp.10-20
• /
• 2020

연구목적: 터널구조물 유지관리계측의 현장점검 결과를 분석하여 개선방안을 제시한다. 연구방법: 도심지에서 건설되고 있는 서울지하철◯호선 14개 공구의 터널구조물을 대상으로 유지관리계측에 대한 다양한 항목의 문제점을 조사하고 분석을 실시하였다. 연구결과: 유지관리 계측 항목과 계측수량 및 설치위치는 개착터널과 굴착터널로 구분하여 개선방안을 제시하였다. 계측기기의 내구연한은 각종 기준을 검토하였고, 내구성 확인방법은 계측센서의 승인 및 검수, 검사 및 시험, 검정 및 교정 등의 개선방안을 제시하였다. 결론: 터널구조물 유지관리계측의 개선방안을 건설현장에 적용하면 유지관리계측의 효율성이 증대되고 건설계측 기술발전에 기여할 것이다.

• 한국산학기술학회논문지
• /
• 제19권10호
• /
• pp.82-88
• /
• 2018

방어용 무기체계 중 하나인 기만체계는 소모성 방식으로, One-shot system에 해당된다. 주기적 점검을 통해 신뢰도를 유지하며, 발사를 해보아야 정상 작동여부를 확인할 수 있어 고신뢰도가 요구된다. 본 논문에서 분석하고자 하는 기만체계는 개발 시 목표 신뢰도 설정 및 신뢰도 예측 없이 정비주기가 설정되었다. 그러나 현재 군에서 운용 중인 수량이 점점 증가하여 정비주기 최적화 필요성이 대두되었다. 이에 따라 수십 년간 지속적으로 운용된 기만체계의 정비 데이터를 통하여 신뢰도를 분석하고 최적 정비주기를 제시하였다. 2장에서 신뢰도 분석에 사용된 데이터 수집 및 분류방법을 제시하였으며, 분석 방법론에 대해 간략하게 소개하였다. 이를 토대로 3장에서 데이터에 대한 분포 분석 및 적합도 검증을 통해 본 기만체계 정비 데이터는 와이블 분포를 적용 하는 것이 가장 적합함을 확인하였으며, 와이블 분포의 형상 및 척도모수를 추정하였다. 4장에서는 도출된 분포를 통해 백분위수, 생존확률, MTBF 분석결과를 제시하였다. 또한 시간별 신뢰도 분석결과를 통해 적정 정비주기를 도출하였다. 5장 결론에서는 향후 본 연구결과에 대한 향후 활용방안을 제시하였다.

• 한국신뢰성학회지:신뢰성응용연구
• /
• 제16권3호
• /
• pp.257-262
• /
• 2016

Recently, the subject of reliability attracts a great deal of domestic and international attentions and the extensive research activities are being conducted as well. Such trend exists mainly due to the fact that the research on the subject of reliability not only contributes to the theoretical developments, but also may find a wide range of applications in practice over several fields. In particular, the research regarding the maintenance policy incorporating certain types of warranty for repairable system and its application is being performed extensively by many researchers, and their efforts seem more concentrated on developing new maintenance policies which minimize the expected operating cost incurred for replacement and repair of the system, while keeping the system at high reliability. Effective maintenance policy may reduce the operating cost and decrease the downtime of the system during its mission period and consequently, increase the productivity of the system. In this article, the major areas of interest in the field of reliability and its historic perspectives are given briefly and the theoretical aspects in several fields of reliability including the maintenance and warranty policies is also discussed. Furthermore, the current domestic situation regarding the education and research on reliability is presented, along with the importance of reliability theory and the difficulty of training reliability personnel. Finally, the author's opinion for effective education system is proposed.

• Safety and Health at Work
• /
• 제7권2호
• /
• pp.120-123
• /
• 2016

Background: To assess in a laboratory setting the ability to stay awake in a sample of workers of an Italian hospital and to investigate the association between that ability and the risk of occupational injury. Methods: Nine workers at the University Hospital of Udine who reported an occupational injury in the study period (cases), and seven noninjured workers (controls) underwent a polysomnography and four 40-minute maintenance of wakefulness tests (MWT). Differences in sleep characteristics and in wakefulness maintenance were assessed using Wilcoxon's rank sums tests and Fisher's exact tests. Results: Controls had greater sleep latency, lower total sleep time, fewer leg movements, and a higher percentage ratio of cycling alternating pattern, were more likely not to fall asleep during the MWT and were less likely to have two or more sleep onsets. Although not all the differences reached statistical significance, cases had lower sleep onset times in Trials 1-3. Conclusion: In the literature, the evidence of an association between MWT results and real life risk of accidents is weak. Our results suggest a relationship between the MWT results and the risk of injury among hospital workers.

• 한국임상약학회지
• /
• 제32권3호
• /
• pp.238-250
• /
• 2022

Objective: The aim of this study was to examine the impact of ATP-binding cassette subfamily B member 1 (ABCB1) C3435T polymorphism on the treatment response of patients to vitamin K antagonists (VKAs). Methods: In this systematic review and meta-analysis, the PubMed/Medline, Embase, and Cochrane Library databases were searched for eligible articles for the period up to November 2020. Articles that reported treatment response to VKAs according to the ABCB1 C3435T polymorphism were included in this study. Results: A total of 13 and 9 articles were included in the systematic review and meta-analysis, respectively. The weekly maintenance dose of warfarin was significantly lower in patients with the ABCB1 3435CT or TT polymorphism type than in those with the ABCB1 3435CC type (weighted mean difference [WMD], -2.53 mg/week; 95% confidence interval [CI], -3.64 to -1.43, p<0.001). However, the weekly maintenance dose of acenocoumarol was not significantly associated with the ABCB1 C3435T polymorphism (WMD, 1.02; 95% CI, -0.61 to 2.65, p=0.22). Conclusion: The ABCB1 C3435T polymorphism was significantly associated with the weekly maintenance dose of warfarin. Further research is needed to confirm the association between the ABCB1 C3435T polymorphism and the incidence rate of bleeding events.

• Journal of Information Technology Applications and Management
• /
• 제22권3호
• /
• pp.143-167
• /
• 2015

This paper addresses the issue how the total life cycle cost may be minimized and how the cost should be allocated to the acquirer and developer. This paper differentiates post life cycle change (PLCC) endeavors from PLCC activities, rigorously classifies PLCC endeavors according to the result of PLCC endeavors, and rigorously defines the life cycle cost of a software product. This paper reviews classical definitions of software 'maintenance' types and proposes a new typology of PLCC activities too. The proposed classification schemes are exhaustive and mutually exclusive, and provide a new paradigm to review existing literatures regarding software cost estimation, software 'maintenance,' software evolution, and software architecture from a new perspective. This paper argues that the long-term interest of the acquirer is not protected properly because warranty period is typically too short and because the main concern of warranty service is given to removing the defects detected easily. Based on the observation that defects are caused solely by errors the developer has committed for software while defects are often induced by using for hardware (so, this paper cautiously proposes not to use the term 'maintenance' at all for software), this paper argues that the cost to remove defects should not be borne by the acquirer for software.