• 한국구조물진단유지관리공학회 논문집
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• 제19권2호
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• pp.52-59
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• 2015

본 논문에서는 효과적인 제진설계를 구현하기 위한 설계기술 개발의 일환으로 20층 라멘조 형식의 공동주택을 대상으로 최근 개발된 등 방성감쇠장치 (일명 카고메감쇠장치)를 적용하여 대상구조물-카고메감쇠장치-지지구조물로 구성된 새로운 형식의 시스템 (Kagome Damper System : KGDS)을 제안하고, 대상구조물과 지지구조물의 강성차, 감쇠장치의 크기 및 지지구조물의 적용 층수 등을 변수로 수치해석을 수행하여 제진효과를 검토해 보았다. 해석결과, 밑면전단력과 최상층 최대응답변위 감소라는 관점에서 유효한 제진효과를 얻기 위해서는 지지구조물을 3개층 높이로 설치할 경우, 대상구조물과 지지구조물 간의 강성비는 약 6.4배 이상, 감쇠장치의 사이즈는 $700{\times}700mm$ 이상을 확보할 필요가 있으며, 지지구조물을 5개층 높이로 설치할 경우에는 대상구조물과 지지구조물 간의 강성비는 약 7.0배 이상, 감쇠장치의 사이즈는 $500{\times}500mm$ 이상을 확보할 필요가 있는 것으로 판단된다.

• 조명전기설비학회논문지
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• 제29권4호
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• pp.18-29
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• 2015

The purposes of this research and development are as follows: first, to provide pleasant driving environments inside tunnels; second, to improve the current illumination environments lacking in diffusion luminance meters to meet tunnel lighting standards; and, third, to reduce the consumption of tunnel lighting energy accounting for approximately 65% of tunnel maintenance costs because of inadequate visual environments and tunnel operations. Further details are listed below. Firstly, an image luminance meter for tunnels that can implement the L20-method which is a tunnel luminance method that follows the international standards of CIE88, which was developed in order to improve and change the existing illumination-based tunnel lighting operation system to a luminance-based system. (The margin of error of below 5% according to the results of a test by an authorized agency and field test). Secondly, early illumination control is possible since the lighting control system that can be operated based on luminance enables interlocking control of the inside and outside of a tunnel using ethernet communication. Thirdly, guidelines for field application of the system are proposed. In addition, the luminance inducers of tunnels are found and the reflexibility of each facility that may reduce luminance of the boundaries is also proposed. Fourthly, as a result of a test bed, power consumption of luminance-based lighting operations decreased by 15.6% compared to illumination-based operations. Applying the feedback controls and maintenance factors of internal/external luminance meters, it reduced by 36.4%. Therefore, we became able to provide a luminance-based lighting operation system that complies with tunnel lighting design standards and provides a visual environment for drivers.

• 한국주거학회논문집
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• 제23권2호
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• pp.89-98
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• 2012

As the construction of multi-family housings, especially apartments, has been increased since 1970s, the multi-family housing becomes one of the main housing types in Korea. With the increase of multi-family housings, managing them becomes an important issue. Since 2010, the government has made a lowest price award system by a competitive bid compulsory to promote the development of housing management systems. Although competitive bids were implemented, the maintenance company was finally selected by the price without any other consideration. Consequently, the quality of management service was not enhanced. The purpose of this study is to suggest the improvement scheme of multi-family housing management system. In this study, the bidding data of "K-apt", the bidding method and the successful tendered price are analyzed. The results of analyzing bidding materials, the proportion of applying a lowest price system was 67.7%. Also many diverse ways to select the best management company were used, but most of these ways were violate the law and guidelines of Ministry of Land, Transport and Maritime Affairs. It meant that the lowest price award system was not implemented by strict standards and didn't correspond with the needs of residents of apartment. This condition made the housing maintenance quality low and deteriorated the management industry development. To enhance this condition, a new standard to select the management company, which are included contents of quality of managing quality, management expenses and companies' soundness, is necessary.

• 한국농공학회논문집
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• 제60권2호
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• pp.103-110
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• 2018

Most of the intake facilities of small agricultural reservoirs are conduits and they are regarded as serious defects due to the structural weakness that penetrates the body of the dam, and countermeasures are needed. This study suggests the application method of siphon type water intake facility by hydraulic model test and physical scale model test of siphon type water intake facility which has high safety and easy maintenance. Experimental results show that sufficient flow rate can be secured for the purpose of intaking water according to the differential head between the reservoir and the discharge part, and the flow rate can be controlled by the valve. The negative pressure was -31.5 kPa, and vibration and noise did not occur during the operation of the siphon. The maximum flow velocity in the discharge outlet was 1.11 m/s which meets the criterion for irrigation canals. Therefore, scour risk would be very low. As a result of the inflow distribution experiment, even if the inflow part is separated by only about 0.8 m, the flow velocity is remarkably decreased, so that the clogging by debris would not appear. When the pump was operated only once for the first time and the inside of the siphon was filled with water, continuous operation was possible by only valve operation. The results of this study are expected to be used for the design guidelines of the water intake facilities and improve safety and maintenance convenience of agricultural reservoirs.

• 한국철도학회논문집
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• 제17권1호
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• pp.52-58
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• 2014

노반 성토체에서 발생하는 소성 변형은 콘크리트 궤도의 안정성과 유지보수에 영향을 미친다. 철도 노반에서의 장기적인 소성 변형은 주로 반복적인 열차 통과로 발생하는 누적된 비탄성적 변형률에 의해 발생한다. 누적 소성 변형의 예측은 궤도의 유지보수와 열차의 안전한 운영을 위해서 중요하다. 본 연구에서는 서로 다른 강화노반 두께를 가진 철도노반에서 발생하는 연직 변위를 계산하였다. 누적 소성 변형률을 계산하기 위한 멱함수의 상수는 삼축 실험과 실대형 재하 실험의 결과로부터 구하였다. 표준 노반 단면에 대한 3차원 유한요소해석 결과로부터 강화노반의 두께를 선정하는 가이드라인을 제시하였다.

• 대한치과보철학회지
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• 제58권4호
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• pp.385-391
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• 2020

의치 접착제는 의치의 유지와 안정을 향상시키기 위해 사용하는 재료로, 용해성과 비용해성으로 구분된다. 의치 접착제는 의치의 유지와 안정, 환자의 저작 기능 향상에 도움을 준다. 세정 등 위생관리가 잘 이루어져야 하며, 지지 조직 상태 및 의치의 적합을 평가하기 위한 주기적인 검진이 필수적이다. 수많은 치과의사들은 의치 접착제의 효과에 대해 막연히 알고만 있을 뿐, 사용 시 주의사항이나 관리 방법에 관해서는 제조사의 지시에 의존하는 경우가 많다. 본 논문에서는 의치 접착제의 성질, 효과, 사용 시 주의사항을 살펴보고, 환자와 전문가를 위한 임상적 지침을 제시하고자 하였다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제23권4호
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• pp.356-365
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• 2020

Purpose: There have been many efforts to develop generalizable severity markers in children with acute pancreatitis (AP). Expert opinion panels have developed consensus guidelines on management but it is unclear if these are sufficient or valid. Our study aims to assess the effect of clinical and laboratory variables, in addition to treatment modality on hospital length of stay (LOS) as a proxy variable for severity in pediatric patients admitted with AP. Methods: We conducted a retrospective chart review of patients between ages of 0-18 years, who were admitted with AP at 2 institutions between 2013-2018, John R. Oishei Children's Hospital (Buffalo, NY, USA) and Medical University of South Carolina Children's Hospital (Charleston, SC, USA). We constructed three linear regression models to analyze the effect of clinical signs of organ dysfunction, laboratory markers and fluid intake on hospital LOS. Results: Ninety-two patients were included in the study. The mean age was 12 years (range, 7.6-17.4 years), 55% were females, and median LOS was 3 days. The most frequent cause of AP was idiopathic. Our study showed that elevated blood urea nitrogen (BUN) on admission (p<0.005), tachycardia that lasted for ≥48 hours (p<0.001) and need for fluid resuscitation were associated with increase LOS. Total daily fluid intake above maintenance did not have a significant effect on the primary outcome (p=0.49). Conclusion: Elevated serum BUN on admission, persistent tachycardia and need for fluid resuscitation were associated with increase LOS in pediatric AP. Daily total fluid intake above recommended maintenance did not reduce LOS.

• 토지주택연구
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• 제3권1호
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• pp.97-109
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• 2012

현재 지하차도 설계 지하수위는 철도, 지하철 및 공동구의 설계기준과 기존사례를 준용하여 지표면 이하 1.0m를 기준으로 설계하고 있으며, 대부분 과다설계 요인과 친환경적이지 못하다는 지적받고 있는 부력방지 앵커공법이 모든 현장에 획일적으로 적용되고 있다. 본 연구에서는 영종하늘도시 사업지구에 시공중인 지하차도 구조물과 관련하여 국내외 지하차도 설계, 유지관리 현황을 조사하고 지하수 유도배수계획의 현장 적용성을 검토하여 지하차도 유도배수공법의최적 설계방안 및 유지관리 가이드라인을 제시하고자 하였다. 특히, 본 연구유역을 중심으로한 유출지하수에 대한 대체수자원 활용방안 등은 향후 지하차도 부력방지공법의 가이드라인으로 매우 유용하게 활용될 수 있을 것으로 판단된다.

• 한국구조물진단유지관리공학회 논문집
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• 제18권6호
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• pp.21-29
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• 2014

본 연구에서는 모노파일지지구조의 고성능 그라우트연결부의 부착거동을 다루고 있다. 강관파일 연결부의 일체화를 위하여 섬유보강 고성능 그라우트를 개발하였으며, 재령 7일 압축강도 125MPa와 직인장강도 7.5MPa를 나타내었다. 축하중을 받는 상태에서의 그라우트의 부착거동을 평가하기 위하여 강관파일에 그라우트를 충진하여 부착실험을 수행하였으며, 그 결과를 기존의 설계기준과 분석하였다. 실험변수는 섬유혼입율 (0%, 0.5% and 0.9%), 섬유의 형상비 (60 and 80)와 전단키의 높이와 간격의 비 (0.013 and 0.056)로 선정하였다. 실험결과 최대부착강도는 30.8MPa로 관찰되었으며, 섬유 혼입율보다는 전단키의 높이와 간격의 비가 부착강도에 영향을 미치는 것으로 분석되었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.117-129
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• 2009

This paper studied the safety management network system of infrastructure which constructed smart sensors, closed-circuit television(CCTV) and monitoring system. This safety management of infrastructure applied to bridge, cut slop and tunnel, embankment etc. The system applied to technologies of standardization guidelines, data acquirement technologies, data analysis and judgment technologies, system integration setup technology, and IT technologies. It was constructed safety management network system of various infrastructure to improve efficient management and operation for many infrastructure. Integrated safety management network system of infrastructure consisted of the real-time structural health monitoring system of each infrastructure, integrated control center, measured data transmission using i of tet web-based, collecting data using sf ver, early alarm system which the dangerous event of infrastructure occurred. Integrated control center consisted of conference room, control room to manage and analysis the data, server room to present the measured data and to collect the raw data. Early alarm system proposed realization of warning and response within 5 minute or less through development of sensor-based progress report and propagation automation system using the media such as MMS, VMS, EMS, FMS, SMS and web services of report and propagation. Based on this, the most effective u-Infrastructure Safety Management System is expected to be stably established at a less cost, thus making people's life more comfortable. Information obtained from such systems could be useful for maintenance or structural safety evaluation of existing structures, rapid evaluation of conditions of damaged structures after an earthquake, estimation of residual life of structures, repair and retrofitting of structures, maintenance, management or rehabilitation of historical structures.