• Journal of Environmental Impact Assessment
• /
• v.27 no.1
• /
• pp.73-82
• /
• 2018

The purpose of this study is the evaluation of the impact of increase in impervious areas due to urbanization on the pollutant discharge using the HSPF model at Musim watershed. Model calibration and validation were performed based on the observed data 2015 and 2014, all simulation items have been successfully simulated such as flow, BOD, and TP. The land cover map used in the model reflected on the land use status of the Musim watershed in 2015 and the application of the development areas and locations. As a result of simulation, during rainfall daily pollutant load with the increased impervious land increased more than that before the development. However, the pollutant load decreased during the non-rainfall time. Annual pollutant load in rainfall time was significantly higher than that in non-rainfall time, BOD and TP increased. The simulation of non-point source pollutant load was applied under two assumptions, such as the increased area of impervious land and the non-change number of point source load before and after development. As the result of a simulation, the non-point source pollutant load after development was bigger than those before development. It was necessary to take measures to control non-point source pollution at the consideration status of development.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2005.04a
• /
• pp.719-726
• /
• 2005

The optimal design was performed for the bridge superstructure composed of steel box girders and concrete deck considering life cycle cost. The service life of the superstructure was estimated, after load carry capacity curves for steel girder and concrete deck were derived on the basis of condition grade curves and maintenance histories. The object function was determined as life cycle cost, including initial cost, total maintenance cost, disposal cost and user cost, for a period of the estimated service life. The optimal design of the superstructure was performed for the various service lifes. The annual costs were used to compare calculated results and to get the most economical design. Also this paper presents reasonable idea for the use of user cost with uncertainty.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2006.05a
• /
• pp.894-898
• /
• 2006

A model, which can analyze the hydrological performance for small hydropower(SHP) plants having no flow duration characteristics has been studied and developed. System performance of existing SHP plant under operating was analyzed by using the developed model. The annual operational rate of SHP plant showed that the data were in good agreement with predicted results from the model. Based on these results, several SHP sites to be exploited were selected and the performance characteristics were analyzed by using the developed model. Also, primary design values such as design flow rate, plant capacity, and operational rate were suggested. As a result, it was found that the methodology used in this study is useful tool to predict the hydrological system performances of SHP sites.

• Proceedings of the KIPE Conference
• /
• 2011.07a
• /
• pp.504-505
• /
• 2011

Decreasing actual greenhouse gas will be difficult if it is not solved addressed in architectural fields. Zero emission building or zero energy building, maximize the efficiency of energy, which means the building can operate by their own renewable energy facility without any other supplying. To be a zero emission building, a building needs realization of high efficiency low energy consumption, construction of building its own energy production facilities and lastly a power grid connection. According to increasing of DC load about TV, LED lighting, computer, IT in building for living and business, it is expected the save of energy when the system of AC power distribution change into the system of DC power distribution. Renewable energy exists a big different rate produced by outside environment. When electrical power overproduce, it can supply for system. Otherwise, if electrical power produce less, it can receive supply from system. Send and receive power can lead to zero to annual standard. This paper shows the simulation about efficient control of power conversion which is related to DC power distribution of architecture and DC output of renewable energy by using L-type converter.

• Journal of Korean Institute of Industrial Engineers
• /
• v.27 no.3
• /
• pp.281-288
• /
• 2001

We consider in this article a multi-objective part-machine grouping problem in which parts have alternative process plans and expected annual demand of each part is known. This problem is characterized as optimally determining part sets and corresponding machine cells such that total sum of distance (or dissimilarity) between parts and total sum of load differences between machines are simultaneously minimized. Two heuristic algorithms are proposed, and examples are given to compare the performance of the algorithms.

• Proceedings of the KIEE Conference
• /
• 2006.07a
• /
• pp.76-77
• /
• 2006

본 연구를 통하여 전력수급계획에 필요한 연간 시간대별 총수요를 예측하는 산법을 개발하였다. 예측과정은 크게 평상일 예측과 특수일 예측으로 구분된다. 평상일의 경우는, 연중 최대수요가 발생하는 하절기 기상으로부터 연중 최대수요를 예측한 다음, 하향식 접근에 의해 주간-일간-시간대별 평상일 수요를 예측하며, 특수일 수요는 예측된 평상일 수요와 평상일 대비 상대계수 모형으로부터 예측한다. 예측의 정확도를 개선하기 위하여 시계열 자료에 가중치를 부여하고, 실적자료가 생길 때마다 자동으로 모형이 갱신되도록 하였으며, 수요예측 결과를 검증, 보정하기 위해 주간수요예측을 재수행할 수 있다. 또한 계획된 월간 전력량 제약에 협조하는 예측산법도 포함하였다.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.48 no.10
• /
• pp.1198-1205
• /
• 1999

This study is focused on the reliability evaluation for distribution system based on deterministic evaluation technique. Average failure rates, average outage time, and average annual outage time of electrical parts and load points are calculated through network reduction method and failure mode & effective analysis method. And reliability indices of distribution system are calculated. Finally, by employing analytic hierarchy process method, unique index which evaluates and improves the distribution system is calculated. As a result, finding weak points and expansion schedule of the system is possible. The usefulness of this method is verified by applying it to the Inchon International Airport.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1996.04a
• /
• pp.470-472
• /
• 1996

POSCO has a plan for facility expansion in plate mill by building No.3 Plate Mill. By No.3 Plate Mill's coming on line, POSCO' current plate production of 2.3 million tons will increase by over 1 million tons to 3.36 million tons (Currently, annual domestic demand for plates is 4.42 million tons). With the plan of facility expansion, POSCO also has the plan of integrating the Plate Warehouse. But, we came to have a question whether the roller table from the mill to the warehouse could carry extended products. Engineers working in the mill wanted to install transfer facility to reduce the load of the roller table, but the engineers in facility purchasing team didn't want to buy the new facility. So, We needed to analyzed the material flow by simulation. The simulation was done on the VAX system by SLAM II. And this project was done by two engineers for 2 months. In the end, we concluded that two transfer facilities are needed for material flow with no bottle neck point.

• Annual Conference on Human and Language Technology
• /
• 1996.10a
• /
• pp.301-307
• /
• 1996

다국어 자동번역이란 2개국어 이상 언어들간의 번역을 말한다. 기존의 다국어 자동번역 시스템은 크게 변환기반 transfer-based 방식과 피봇방식으로 분류될 수 있는데 변환기반 다국어 자동번역 시스템에서는 각 언어의 분석과 생성 규칙이 상이하게 작성됨으로써 언어들간의 공통성이 수용되지 못하였고 그로 인해 전체 번역 메모리의 크기가 증가하는 결과를 초래하였었다. 또한 기존의 피봇방식에서는 다국어에 적용될 수 있는 언어학적 보편성 모델을 구현하는 어려움이 있었다. 이러한 기존의 다국어 자동번역 시스템의 단점들을 극복하기 위해 본 논문에서는 언어들간의 공통성을 수용하며 또한 여러 언어에서 공유될 수 있는 공통 규칙에 의한 다국어 자동번역 시스템을 제안하고자 한다. 공통 규칙의 장점은 전산학적으로는 여러 언어에서 단지 한번 load 되기 때문에 전체 번역 메모리의 크기를 줄일 수 있다는 것과 언어학적으로는 문법 정보의 작성.수정.관리의 일관성을 유지할 수 있다는 것이다.

• Journal of Korean Society on Water Environment
• /
• v.22 no.6
• /
• pp.1088-1093
• /
• 2006

In this study, the method of annual sediment estimation for reservoir long-term operation is proposed. Long-term daily precipitation and evaporation are predicted by Markov Chain. Using these values, reservoir inflow is simulated by NWS-PC model. Reservoir sediment load is estimated by sediment rating relation curve which is observed. From the simulation results, it was found that each simulated value by Markov Chain and NWS-PC was well compared to the observed ones and also estimated reservoir sediment was appropriate to the compared values using empirical equations. It is thought that the proposed method for estimation of reservoir sediment can be useful used to operate the reservoir.