In this study, we analyzed how the revenue water ratio(RWR) is affected by changes in conditions of the water supply area, such as the ratio of aging pipes, maintenance conditions, and revenue water. As a result of analyzing the impact of pipe aging and maintenance conditions on the RWR, it was confirmed that the RWR could be decreased if the pipe replacement project to improve the aging pipe ratio was not carried out and proper maintenance costs were not secured. It was also confirmed that an increase in the revenue water could be operated to facilitate the achievement of the project’s target RWR. In contrast, a decrease in the revenue water due to a population reduction could affect the failure of the target RWR. In addition to analyzing the causes of variation in the RWR, the calculation of estimated project costs was considered by using leakage reduction instead of RWR from recent RWR improvement project cost data. From this analysis, it was reviewed whether the project costs planned to achieve the target RWR of the RWR improvement project in A city were appropriate. In conclusion, the RWR could be affected by variations in the ratio of aging pipes, maintenance conditions, and revenue water, and it was reasonable to consider not only the construction input but also the input related to RWR improvement, such as leakage reduction, when calculating the project cost.

of hazardous risk factors, risk estimation and determination steps by reflecting the trend of overseas risk assessment. METHODS : In deriving, estimating and determining risk factors, comparing the procedures presented by the ILO with the domestic guidline to find out the differences in procedural. and, According to the domestic manual, after setting the criteria for determining a deterministic perspective, analyze the risk assessment data of a specific domestic company and three overseas risk assessment research data to analyze the differences in methodology domestic and abroad. RESULTS : Within the country, there is a possibility that a deterministic view may be applied to all stages of procedure, and certain corporate data to the risk estimation and determination stage. In the case of overseas, the trend of applying deterministic perspectives to the risk determination stage was confirmed. CONCLUSIONS : Present the need for a standard model for improving deterministic methods in the other two stages, excluding risk determination in the domestic evaluation procedure.

As the environmental impacts of fossil fuel energy sources increase, the South Korean government has tried to change non-environmental- friendly enery sources to environmental-friendly energy sources in order to mitigate environmental effects, which lead to global warming and air pollution. With both a limited budget and limited time, it is essential to accurately evaluate the economic and environmental effects of renewable energy projects for the efficient and effective operation of renewable energy plants. Although the traditional economic evaluation methods are not ideal for evaluating the economic impacts of renewable energy projects, they can still be used for this purpose. Renewable energy projects involve many risks due to various uncertainties. For this reason, this study utilizes a real option method, the Geske compound model, to evaluate the renewable energy projects on Jeju Island in terms of economic and environmental values. This study has developed an economic evaluation model based on the Geske compound model to investigate the influences of flexibility and uncertainty factors on the evaluation process. This study further conducts a sensitivity analysis to examine how two uncertainty factors (namely, investment cost and wind energy production) influence the economic and environmental value of renewable energy projects.

DEA(data envelopment analysis) is a technique for evaluation of relative efficiency of decision making units (DMUs) that have multiple input and output. A DEA model measures the efficiency of a DMU by the relative position of the DMU’s input and output in the production possibility set defined by the input and output of the DMUs being compared. In this paper, we proposed several DEA models measuring the multi-period efficiency of a DMU. First, we defined the input and output data that make a production possibility set as the spanning set. We proposed several spanning sets containing input and output of entire periods for measuring the multi-period efficiency of a DMU. We defined the production possibility sets with the proposed spanning sets and gave DEA models under the production possibility sets. Some models measure the efficiency score of each period of a DMU and others measure the integrated efficiency score of the DMU over the entire period. For the test, we applied the models to the sample data set from a long term university student training project. The results show that the suggested models may have the better discrimination power than CCR based results while the ranking of DMUs is not different.

우리나라의 조선해양플랜트 산업은 2011~2015년 기간에 우리나라 품목별 수출기여도에서 1~4위를 차지할 정도로 대한민국 경제성장을 견인하는 중요한 산업이다. 이 연구는 과거 건조에만 치중했던 우리나라 해양플랜트 시추설비의 산업구조에서 통합시운전의 서비스 공급이 가능한 비즈니스 모델을 검토함으로써 시추설비 시장에서 우리나라 조선소의 국가경쟁력을 향상시킬 수 있는 방안을 제안 하고자 하였다. 2014년에 시도된 주작-1 폐공을 활용한 시운전 서비스 모델과 이의 한계 사항을 극복하고 사업을 활성화하기 위한 새로운 제안 비즈니스모델인 수심 150미터급 시운전 전용 모델의 경제성을 검토하였다. 경제성 평가 결과, 수심 150미터급 모델이 경제적으로 더 효과적인 것으로 나타났다. 그리고 통합시추설비의 시운전이 연간 2회에서 3,4,5회로 늘어남에 따라 NPV와 IRR 및 B/C 비율이 모두 증가 하였으며, 1회당 사용료는 감소하는 것으로 나타났다. 따라서 해양시추설비의 통합시운전 사업은 우리나라에서 건조되어 인도되는 설비를 대상으로 시추 시운전을 적극적으로 유치하는 노력이 필요하다.

해양경찰은 바다라는 극한 환경에서 임무수행 중 빈번히 사망·실종의 위험에 맞닥뜨린다. 사고 발생 시 신속한 신원확인을 위해 해양경찰연구센터는 해양경찰을 대상으로 DNA를 이용한 신원확인 시스템을 구축하였으며 사체가 발견되지 않을 경우를 대비해 국립 묘지 안장이 가능한 장치 또한 마련하였다. 순직· 실종 등 대비 신원확인용 인체유래물 보관사업 운영규칙에 따라 인체유래물의 관리, 보 관, 폐기, 품질검사가 진행되며 이는 관리위원회의 감시하에 행해진다. 한반도 해역에서는 매년 700여건의 해양 변사자가 발생하는데 사체가 늦게 발견되어 부패가 심하거나, 일부분만 발견되어 지문 또는 치아로 개인 식별이 불가능할 경우 해양 변사자의 신원확인을 위한 방법이 필요하다. 해양경찰연구센터가 운영중인 ‘인체유래물 보관사업’을 해양·수산 종사자, 관련 연구자, 해양 레저인에게까지 확대 실행 한다면 해양 변사자 신원확인에 큰 도움이 될 것이다.

It is considered necessary to renewal a considerable number of water supply facilities in Korea because they began to be intensively buried in the period of rapid economic growth. Accordingly, local water providers are required to take measures against this situation, but they have currently been caught in a vicious circle of the lack of budget spent in renewing water supply facilities because county-based small-scale local water supply cannot afford to cover annual expenditures with their revenues from water rates. Therefore, this study developed an optimal renewal planning model capable of achieving a balance of financial revenue and expenditure in local water supply using nonlinear programming and furthermore of minimizing the total cost incurred during the analysis. To this end, this study selected the water supply area located in County Y as a research area to build the financial revenue and expenditure and used Solver function provided by Microsoft Excel to use nonlinear programming. As a result, this study developed an optimal renewal planning model minimizing incurred costs in consideration of 6 items in the financial revenue and expenditure. The optimal renewal plan was modeled according to the available annual budget. As a result, this study proposed SICD, a scenario to minimize total costs from the perspective of water suppliers, and SITS, a scenario to minimize the increase in water rates from the perspective of consumers. It can be said that the method proposed in this study is the core of the optimal financial and renewal plans as a final stage of asset management for water supply facilities. Therefore, it is considered possible for local water providers to use the method proposed in this study according to circumstances for the asset management of water supply facilities.

For the asset management of a water pipe network, it would be necessary to understand the extent of the maintenance cost required for the water pipe network for the future. This study would develop a method to draw the optimum cost required for the maintenance of the water pipe network in waterworks facilities to maintain the aim revenue water ratio and to achieve the target revenue water ratio, considering the water service providers’ waterworks condition and revenue water ratio comprehensively. This study conducted a survey with 96 water service providers as of the early 2015 and developed models to estimate the optimum maintenance cost of the water pipe network, considering the characteristics of the water service providers. Since the correlation coefficient of all the developed models was higher than 0.95, it turned out that it had significant reliability, which was statistically significant. As a result of applying the developed models to the actual water service providers, it was drawn that increasing revenue water ratio to more than a certain level can reduce the maintenance cost of the water pipe network by a great deal. In other words, it is judged that it would be the most efficient to secure the reliability of waterworks management by increasing the short-term revenue water ratio to more than a certain level and gradually increase the revenue water ratio from the long-term perspective. It is expected that the proposed methodology proposed in this study and the results of the study will be used as a basic research for planning the maintenance of water pipe network or establishing a plan for waterworks facilities asset management.

Bridge construction cost estimates have generally been conducted by using historial unit-price(per meter or square meter). The traditional estimating method based on unit-price references can never completely reflect the specialty of cable supported bridge. In this paper, we have developed the system for supporting the approximate construction cost and the quantity estimation based on 3D model information in the pre-project planning phase of 3-span continuous suspension bridge with 2-pylons. First of all, we’d analyzed the design information (such as structural design report, blueprint and quantity) and the real cost data from the existing suspension bridges and derived the design variables of the bridges. We developed the BIM wizard that generates a suspension bridge model parametrically based on derived design variables. The principle material quantities of suspension bridge are calculated directly from 3-dimensional bridge model built by using the BIM wizard. We have established the system that the construction cost can be estimated more specific than the traditional estimating method.

This research carried out an analysis on input cost and leakage reduction effect by leakage reduction method, focusing on the project for establishing an optimal water pipe network management system in the Taebaek region, which has been executed annually since 2009. Based on the result, optimal cost-benefit analysis models for water distribution network rehabilitation project were developed using DEA(data envelopment analysis) and multiple regression analysis, which have been widely utilized for efficiency analysis in public and other projects. DEA and multiple regression analysis were carried out by applying 4 analytical methods involving different ratios and costs. The result showed that the models involving the analytical methods 2 and 4 were of low significance (which therefore were excluded), and only the models involving the analytical methods 1 and 3 were suitable. From the result it was judged that the leakage management method to be executed with the highest priority for the improvement of revenue water ratio was installation of pressure reduction valve, followed by replacement of water distribution pipe, replacement of water supply pipe, and then leakage detection and repair; and that the execution of leakage management methods in this order would be most economical. In addition, replacement of water meter was also shown to be necessary in case there were a large number of defective water meters.

This study suggests a safety management model for construction management (CM) suitable to domestic conditions so that inefficiency resulted from the operation of construction projects by public and private institutes according to different systems can be eliminated for the securing of systematic and efficient safety management. Based on the suggested safety management model, this study also develops a safety management information system that can efficiently and consistently manage and maintain a large quantity of information, and give necessary supports in a speedy way in the managing of construction projects.

Construction Management(CM) system, which was introduced some years ago to large national construction projects, such as the construction of Incheon New Airport, construction of high-speed railroad and World Cup stadiums, is considered to be still in its early stage and safety at each step of CM is very poorly controlled. In an attempt to improve such inferior safety management of domestic CM, this study made comparative analysis about operation system of safety management with CM system in domestic and abroad. Also suggested the model under consideration with CM, which is suitable for the situation of Korea.