A system has been developed to reduce fluctuation of the indoor temperature in a radiant floor heating system. The system we developed and implemented is called BoilerMan. With the BoilerMan system the hot water circulation pump is controlled by computer software which implements a unique strategy. To minimize the system development time a user-friendly development environment was used. This development environment was useful in the implementation and testing of the efficiency of our strategy. The environment also serves as an easy means for system maintenance. The BoilerMan went through a few test runs against a real apartment house and the result showed significant reductions in the initial temperature overshoots against the target values. It also reduced the operatingtime of the hot water circulation pump. Such positive results were possible due to our unique strategy that exploits heating efficiency information collected from the past run of the very same system. Since the strategy was implemented with embedded software, it makes the BoilerMan flexible, too.

동남아시아는 섬과 강이 많은 지리적 특성과 경제 규모의 급격한 성장으로 새로운 국가시설물이 꾸준히 계획·건설되고 있으나, 국가시설물 안전진단 및 유지관리에 대한 경험과 인식이 부족하여 국가시설물(교량, 댐 등)의 붕괴사고가 지속적으로 발생하고 있다. 이에 따라 국민들의 시설물 안전성에 대한 신뢰도가 저하되고, 사회·경제적 손실 문제에 지속적으로 노출되고 있는 실정이다. 해결방안으로 동남아시아 각국은 주요 국가시설물(도로, 교량, 댐, 항만 등)에 대한 시설물 안전관리체계의 도입을 추구하여 시설물 안전진단 및 유지관리에 필요한 예산 확보의 근거를 마련하고 있으며, 유지관리사업의 일정을 제시하는 시설물 유지 관리 정책개발을 추진해오고 있다. 또한, 시설물 유지관리 정책을 몇 해 전부터 개발하여 시행하고 있는 국가들은 개별로 관리되고 있는 국가시설물의 유지관리에 대한 업무효율성을 증대시키고 기존시설물의 수명연장 및 붕괴사고 감소를 위한 효율적인 시설물 유지관리체계 도입을 추진하고 있다. 본 논문을 통해 동남아시아 각국의 시설물 안전관리 정책개발 및 시설물 유지관리 기술의 현 주소를 소개하고 향후, 이들 시장에 대한 진출방안을 제시하고자 한다.

Recently, due to record breaking temperature and other factors, bridge expansion joint closing, damage of shoe, narrow distance between abutment and deck is occurred frequently. Therefore, traffic flow was interrupted and vehicle damage was occurred because of expansion joint stick out. In this study, in order to reduce damage of expansion joint and other bridge facilities and to ensure safety of infrastructure, field survey and consulting works are performed for 91 bridges that distance between expansion joint is closed. Based on this study, cause of expansion joint closing are analyzed and maintenance strategy is suggested.

In this paper, we developed a predictive model of maintenance and repair cost based on the element-level condition state by using information collected through the inspection/diagnosis of individual bridges for use in maintenance strategy analysis. The reliability of the prediction model can be improved through of big data analysis using various factors and additional data.

The maintenance costs will be increased due to the aging of the bridge. Most of maintenance activity is generally known for preventing and repairing the deterioration by de-icing salts. The objective of this research is to investigate the minimizing strategy of maintenance costs for the deterioration by de-icing slats of highway bridges.

The maintenance costs will be increased due to the aging of the bridge. Thus, the maintenance strategy considering the damage characteristic of elements is needed for the efficient maintenance of the bridge. The objective of this research is to investigate the minimizing strategy of maintenance costs for highway bridges.

A strategy is needed for a regional survey of geosynchronous orbits (GSOs) to monitor known space objects and detect uncataloged space objects. On the basis of the Inter-Agency Debris Committee’s recommendation regarding the protected region of geosynchronous Earth orbit (GEO), target satellites with perigee and apogee of GEO ± 200 km and various inclinations are selected for analysis. The status of the GSO region was analyzed using the satellite distribution based on the orbital characteristics in publicly available two-line element data. Natural perturbation effects cause inactive satellites to drift to two stable longitudinal points. Active satellites usually maintain the designed positions as a result of regular or irregular maneuver operations against their natural drift. To analyze the detection rate of a single optical telescope, 152 out of 412 active satellites and 135 out of 288 inactive satellites in the GSO region were selected on the basis of their visibility at the observation site in Daejeon, Korea. By using various vertical view ranges and various numbers of observations of the GSO region, the detection efficiencies were analyzed for a single night, and the numbers of follow-up observations were determined. The orbital estimation accuracies were also checked using the arc length and number of observed data points to maintain the GSO satellite catalog.

The maintenance costs will be increased due to the aging of the bridge. Thus, the maintenance strategy considering the damage characteristic of elements is needed for the efficient maintenance of the bridge. The objective of this research is that damage characteristic were estimated by analyzing the change in the presence or absence of damage to a structural member of the bridge for the detailed safety inspection conducted two or more times.

The highway bridges required the maintenance have been consistently increased over 8,000. For long term maintenance strategy, it should be focused on utilizing the systemic information from in-depth inspection data. From now, record-based inspection for highway bridges has been usually performed so that it is needed to investigate the in-depth inspection data for identifying the damage characteristics in detail. In this study, with respective to the performance measure of damage characteristic, damage normalization of highway bridges is researched by using the suggested bridge scales such as area, length, vertical distance, number of members. Based on this process, the standard cost for various damages for highway bridges can be estimated and utilized for long-term maintenance strategy.

The in-depth inspection and maintenance process is based on the ‘Special Act on the Safety Control of Public Structures’ and accompanied specific guide. They prescribe the evaluation standard for physical condition and safety on structures. Recently we are faced with the threat coming from the aging of structures and external condition such as climate change. In this study, sustainable and long-term maintenance strategy is derived.

Maintenance cost of bridges is calculated by the scenario that represented reactive maintenance and preventive maintenance strategy. Preventive maintenance strategy is more life cycle cost-effective than reactive maintenance strategy because bridge life is extended through preventive maintenance work.

Infrastructure safety and maintenance management(ISMM) is one of the most important parts for improving level of people's welfare. The government needs to set up their own improvement strategy for ISMM system. This study was initiated to suggest the strategy to improve ISMM system with long term perspective. In order to investigate the current status and problems of ISMM system, this study reviewed various literature related to the issues of the foreign ISMM systems and conducted the interview with ISMM experts. The strategy would be expected greatly to improve the safety and maintenance management system for domestic infrastructure.

생애주기비용을 고려한 교량의 설계 및 유지관리에 있어서, 점검진단, 보수보강 등에 소요되는 직접적인 비용뿐만 아니라 간접적인 비용인 도로이용자비용은 중요한 비용항목으로 고려되고 있다. 직접비용과 비교하여 상대적으로 추정이 곤란한 도로이용자비용의 추정을 위하여 우회도로의 효과를 고려한 이용자지연비용과 차량운행비용의 정식화를 수행하고, 시간지체에 따른 도로이용자비용의 추정을 위한 회귀모델 개발을 위하여 교통해석과 회귀분석을 수행하였다. 개발된 회귀모델을 생애주기 비용 및 성능 기반 유지관리 전략 수립에 적용하여 도로이용자비용이 생애주기분석에 미치는 영향을 분석하고, 개발된 모델의 적용성에 대해서 고찰하였다. 도로이용자비용은 생애주기분석에 기초한 유지관리전략수립에 큰 영향을 미치며, 개발된 회귀모델은 교량의 도로이용자비용의 추정에 실용적으로 활용될 수 있을 것으로 판단된다.

본 연구에서는 생애주기비용을 고려한 성능기반 최적 유지관리 전략 수립 시스템을 개발하였다. 교량 수명동안 비용과 성능이라는 상반되는 목적을 균형있게 만족시킬 수 있는 유지관리 시나리오의 생성을 다중목적 조합최적화 문제로 정식화하고 유전자알고리즘을 적용하였다. 개발된 프로그램을 이용하여 국도 상 강거더 교량의 최적 유지관리 시나리오를 제공하는 과정을 제시하였다. 개발된 시스템은 현재의 교량 유지관리 전략 수립의 방법을 개선하여 교량 관리주체에게 다양한 제약 및 요구조건에 부합하는 최적의 교량 유지관리 시나리오를 제공할 수 있는 효율적인 도구로 활용될 수 있을 것으로 판단된다.