• Construction Engineering and Management
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• v.12 no.5
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• pp.43-54
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• 2011

LCC(Life Cycle Cost) analysis on design process has to be performed for a selection of reasonable and economical design alternatives in highway construction projects. To be performed of LCC analysis, the maintenance data such that are maintenance periods, rate of repair, maintenance cost, and so on are required. Therefore the Hi-Portal System had been developed and the maintenance data has been accumulating in the Korean Expressway Corporation. However, the data are not effectively used because the system have no consideration for LCC concept, and currently, th data are acquired by survey with experts. In the study, it is proposed that the concept of Generally Annual Maintenance are practically and easily used to perform LCC analysis. Some of generally annual maintenance data are suggested through Hi-portal data analysis due to the proposed concept and LCC analysis of a real highway construction project is preformed by comparison with a current approach. From the results, it make sure that the proposed concept are effectively used to preform LCC analysis until during exactly practical data from Hi-Portal system are obtained.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.1
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• pp.113-125
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• 1988

The design flood formulas in Korean river are reviewed from the early historical stage of the river improvement projects to the present situation. The 11 different formulas are selected for the comparative purpose of the each results at the same rainfall and basin characteristics under the same size of the basin. The max. and min. values of the design flood discharge for the same basin deviated almost as large as 400% according to the formula used without respect to the basin size. The remains have big scattering within those deviations. The steps to derive the design flood are very complicated and tedious time consuming process at present applications. However the reaults computed through the steps are quationable in accordance with the lengths of the hydrological historic records and the accuracy of the data observation technique in view of the engineering judgement. The purpose of this review will give the one of the simplest and the reasonable approach to eliminate misleading the determination of the design flood peak.

• Journal of Korean Society of societal Security
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• v.1 no.2
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• pp.53-59
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• 2008

The lack of water resources is becoming a serious issue throughout the world. The water shortage in Korea is expected to increase. Groundwater can be a solution to this matter in some places. Especially, bank filtrations are known to be advantageous over conventional reserviors, even if they have some drawbacks such as their limited location for development and small sizes. The AHP(Analytic Hierarchy Process) is an analytical tool, supported by simple mathematics, which enables one to explicitly rank tangible and intangible factors against each other for the purpose of resolving conflicts or setting priorities. In order to check the applicability of AHP to the evaluation of bank filtration sites, four candidate locations were chosen. They have suffered from problems like water-supply shortage and delayed dam construction. The analysis results are compared with those of the previous study using a conventional method. It is believed that the developed method can a basis for reasonable decision-making regarding bank filtration development.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.884-888
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• 2005

본 연구에서는 국내 적용되고 있는 여러 유출모형의 특성을 분석하여 도시화 전$\cdot$후 유역의 유출특성을 가장 잘 대변할 수 있는 모형을 선정하여 제시하고자 하였다. 국내의 경우 도시화 전$\cdot$후의 유출모의는 개발전을 자연하천유역으로 간주하여 Clark 모형이 사용되고 있으며, 도시화 후에는 도시하천유역에 주로 이용되고 있는 ILLUDAS 모형을 주로 이용하였으나, 최근 들어서는 도시화 전$\cdot$후 모두 Clark 모형을 적용하거나 도시화 후에는 SWMM모형이 사용되고 있다. 그리고, 과거 국내 주로 도시화 후에 적용되어왔던 ILLUDAS 모형은 미국의 Illinois라는 특정지역을 대상으로 개발된 모형이므로 우리나라의 모든 유역에 적용하는 것은 합리적이지 못하고 배수관망이 수리구조물을 포함하고 있는 경우 정확한 유출랑을 산정한다고 보기는 힘들다. 따라서 최근에는 미국에서 전지역적으로 권장되고, 국내에서도 이미 여러 연구를 통해 도시유출모형에서 다른 모형보다 우수함이 검증된 SWMM 모형의 사용이 증가되고 있다. 그러나, 각 모형마다 사용되는 매개변수와 모의과정의 차이가 있으므로 도시화 전$\cdot$후 다른 유출모형을 사용하는 방법은 도시화로 인한 유출특성의 변화뿐만 아니라 다른 모형의 적용으로 인한 모형적인 차이가 발생할 수 있다. 또한, 자연하천유역의 유출분석을 위해 개발된 Clark 모형은 도시화가 된 이후에 적용하기에는 배수관망과 맨홀 등의 분석이 불가하기 때문에 한계점을 내재하고 있다. 따라서, 도시화 전$\cdot$후의 유출특성의 변화를 정확하게 비교 예측하기 위해서는 서로 다른 모형의 적용으로 인해 발생할 수 있는 문제점 검토가 선행되어야 한다. 본 연구를 궁극적인 목적을 위해 도시유출모형의 자연유역에서의 적용성을 검토를 선행하였다. 자연하천 유역인 설마천 유역에 대해 Clark 모형과 SWMM 모형을 적용하여 비교 검토하였다. 연구결과 SWMM 모형의 자연유역 적용 가능성이 입증되었으며 추후 연구과제인 도시화 전$\cdot$후 유출특성 분석시 하나의 모형을 사용하여 유출모형간에 발생할 수 있는 차이를 제거할 수 있는 가능성을 확인할 수 있었다.

• Korean Journal of Construction Engineering and Management
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• v.7 no.6
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• pp.141-150
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• 2006

As the law on the private sector investment in social infrastructure was amended in January of 2005, the government is aggressively promoting BTL projects but many trials and errors and problems are occurring. Especially, the Value-For-Money evaluation conducted by the responsible agencies to judge the appropriateness of the project found there was a conspicuous difference between the computed cost and the final contract sum. Accordingly, this study is aimed to grasp the problems in the current Value-For-Money evaluation and to improve it in order to proceed with BTL projects efficiently. To achieve this, through a relative comparison to the final contract sum, a clear standard for the items of Value-For-Money evaluation was presented and thus, a model that can ensure accuracy in computing the Value-For-Money was established so that a delay in negotiations can be avoided. If the Value-For-Money evaluation established in this study is used in assessing the appropriateness of unit prices for BTL projects for education facilities, a reasonable result can be expected to be drawn in selection and negotiations with contractors, and maintenance and Post-Operation-Evaluation(POE) of education facilities as well.

• Journal of the Korean Institute of Gas
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• v.24 no.5
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• pp.20-28
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• 2020

In this study, the damage impact range in the case of a hydrofluoric acid leak accident was predicted using formula calculation, impact assessment simulations, and CFD simulations, and the results were compared and analyzed with the actual environmental impact report. Formula calculation was performed by using the leak source model and diffusion model. Impact assessment simulation was performed by KORA provided by the Korean Ministry of Environment, ALOHA by the United States Ministry of Environment, and PHAST, which is relatively widely used among commercialization programs, and the STAD-CMM+program for CFD simulation. Was utilized. Considering convenience, speed, acceptability, and economics from the user's perspective, ALOHA and KORA were the most appropriate methods for predicting the impact of hydrofluoric acid leakage. In addition, the results of this study will help to reduce unnecessary regulations in the process of government policy development and optimize the investment in the safety field of the company, effectively utilizing the limited resources of the government and the company.

• Journal of Soil and Groundwater Environment
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• v.8 no.4
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• pp.36-44
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• 2003

The lack of water resources is becoming a serious issue throughout the world. The water shortage in Korea is expected to increase dramatically through 2020. The amount of water shortage could amount to 1.8 and 2.6 billion cubic meters in 2011 and 2020, respectively. Groundwater can be a solution to this matter in some places. Especially, underground dams are known to be advantageous over conventional dams, evert if they have some drawbacks such as their limited location for development and small sizes. The analytic hierarchy process(AHP) is an analytical tool, supported by simple mathematics, which enables one to explicitly rank tangible and intangible factors against each other for the purpose of resolving conflicts or setting priorities. In order to check the applicability of AHP to the evaluation of underground dam sites, lour candidate locations were chosen. They have suffered from problems like water-supply shortage and delayed dam construction. The analysis results are compared with those of the previous study using a conventional method. It is believed that the developed method can provide central or local government with a basis for reasonable decision-making regarding underground dam development.

• Journal of the Korean Society for information Management
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• v.18 no.3
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• pp.285-309
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• 2001

The industry information grows faster than any other information resources in the Internet age. Unfortunately, however, there is no consensus on the standard of the classification among the information providers of the industry fields. This may a problematic issue not only in building a continuous and systematic development of the industry information, but also in the use of the information among the users. This study aims to propose a well-structured and/or an efficient classification scheme for the industry information to help the users with easy to retrieve the Internet resources. To do this, we analyzed the subject classification scheme of the domestic industry information on the web sites, which is largely adopted the \"Korean Standard for the Industry Classification\". In addition, we suggested the principle of the subject classification and their hierarchial structure derived from the analysis of the knowledge and document classification scheme. As a result, it was suggested an optimized industry classification scheme based on the analysis of the validity test of classification item measured by the quantitative analysis of the industry information, which it currently accessible through the Internet. Internet.

• Journal of Korea Water Resources Association
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• v.49 no.11
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• pp.941-949
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• 2016

The flow characteristics of the broad-crested side weir considering the levee's side slope of main channel ($ES_{ch}$) was investigated through hydraulic experiment in order to estimate the discharge coefficient equation. For applicability to actual river, levee's side slope of main channel 1:0.5, 1:1 and 1:2 were selected. Experimental results show that the new estimated equation for the discharge coefficient including $ES_{ch}$ is reasonable and effective in actual applications by comparing estimated and measured discharge over side weirs. Through a multiple linear regression analysis the importance of variabes were ordered as $ES_{ch}$ > $h/y_u$ > $L/y_u$ > $Fr_u$. Especially the discharge coefficient equation without $Fr_u$ was suggested, and the high applicability was reviewed by comparing the measured and calculated overflow of broad-chested side weir.

• Spatial Information Research
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• v.21 no.1
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• pp.37-44
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• 2013

This study sets the boundary of U-City industry based on expert surveys. Based on this U-City industry boundary, an appropriate inter-industry analysis is performed. The result shows production inducement coefficients, value added inducement coefficients, employment & enter employment inducement coefficients, influence coefficients and induction coefficients. Based on these coefficients, overall characteristics and spillover effects of U-City industry are examined. The result of this study shows that U-City industry has bigger value added-induced effects and employee-induced effects than other industry. The result also shows that U-City industry also has a great forward linkage effect. This study has a meaning that could be used to make political decisions as a basic data.