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        검색결과 29

        23.
        2008.11 KCI 등재 서비스 종료(열람 제한)
        This study aims at the analyze of unsteady downstream flow due to dam failure along dam failure scenario and applied to Yeoncheon Dam which was collapsed August 1st 1999, using HEC-RAS simulation model. The boundary conditions of this unsteady flow simulation are that dam failure arrival time could be at 02:45 a.m. August 1st 1999 and failure duration time could be also 30 minutes. Downstream 19.5 km from dam site was simulated for unsteady flow analysis in terms of dam failure and non-failure cases. For the parameter calibration, observed data of Jeonkok station were used and roughness coefficient was applied to simulation model. The result of the peak discharge difference was 2,696 to 1,745 m³/sec along the downstream between dam failure and non-failure and also peak elevation of water level showed meanly 0.6m difference. Those results of these studies show that dam failure scenarios for the unknown failure time and duration were rational because most results were coincident with observed records. And also those results and procedure could suggest how and when dam failure occurs and downstream unsteady flow analyzes.
        24.
        2008.11 KCI 등재 서비스 종료(열람 제한)
        This study aims at the estimation of dam failure time and dam failure scenario analysis of and applied to Yeoncheon Dam which was collapsed August 1st 1999, using HEC-HMS, DAMBRK-FLDWAV simulation model. As the result of the rainfall-runoff simulation, the lancet flood amount of the Yeoncheon Dam site was 10,324 m3/sec and the total outflow was 1,263.90 million m3. For the dam failure time estimation, 13 scenarios were assumed including dam failure duration time and starting time, which reviewed to the runoff results. The simulation time was established with 30 minutes intervals between one o'clock to 4 o'clock in the morning on August 1, 1999 for the setup standard for each case of the dam failure time estimation, considering the arrival time of the flood, when the actually measured water level was sharply raising at Jeongok station area of the Yeoncheon Dam downstream, As results, dam failure arrival time could be estimated at 02:45 a.m., August 1st 1999 and duration time could be also 30 minutes. Those results and procedure could suggest how and when dam failure occurs and analyzes.
        25.
        2008.04 KCI 등재 서비스 종료(열람 제한)
        Until comparatively lately, the annual time series of the SO2 concentration had been shown in a decreasing trend in Ulsan as well as other Korean cities. However, the high concentration of SO2 was frequently found in the specific countermeasure region including the national industrial complex such as Mipo and Onsan in the Ulsan city for the period of 2001∼2004. There are many conditions that can influence the high concentration of SO2 at monitoring sites in Ulsan, such as: First, annual usage of the fuel including sulfur increased in comparison with the year before in spite of the fuel conversion policy which wants to use low sulfur oil less than 3% and LNG. Second, point source, such as the power plants and the petroleum and chemistry stacks, was the biggest contributor in SO2 emission, as a analyzed result of both the air quality modeling and the stack tele-monitoring system (TMS) data. And third, the air pollutants that occurred in processes of burning and manufacturing of the fuel including sulfur were transported slow into a special monitoring site by accumulating along the frontal area of see-breeze. It was concluded that Ulsan's current environmental policy together with control methods should be changed into the regulation on total amount of emission, including a market-based emission trading with calculating of atmospheric environmental critical loads, for the SO2 reduction like the specific countermeasure for the O3 and PM10 reduction in the Seoul metropolitan area. And this change should be started in the big point sources of 1∼3 species because they are big contributors of Ulsan's SO2 pollution. Especially it is necessary to revitalize of the self-regulation environmental management. Other control methods for sustaining the SO2 reduction are as follows: maintenance of the fuel conversion policy, reinforcement of the regional stationary source emission standard, and enlargement of the stack TMS.
        26.
        2006.08 KCI 등재 서비스 종료(열람 제한)
        부산신항만의 개장과 함께 상하이항의 급속한 성장과 센젠항의 서비스와 생산성 신장뿐만 아니라 더욱 활동적인 광양항 등 한국의 항만은 국내외적으로 많은 변화에 직면하고 있다. 새로운 항만에 비교해서 부산항의 컨테이너 터미널들은 오래된 장비와 시설물을 보유하고 있으므로 서비스 수준과 경쟁력을 유지하기 위해 생산성 향상을 위한 리모델링에 착수할 필요성이 있다. 리모델링 활동은 게이트, 안벽, 야드, IT시스템 등에 대한 새로운 기술의 개발과 적용에 의해 지속적으로 시도되어야 한다. 영역별 대안들에 대한 기술적 검토를 위하여 설문조사와 면담조사를 하였으며, 리모델링 우선순위, 기술적용 기간, 적용 방향 등을 통해서 컨테이너터미널의 리모델링 활용계획을 설정하였다.
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