• International Journal of Aeronautical and Space Sciences
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• 제14권3호
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• pp.264-271
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• 2013

A method of multiple transport-aircraft mission modeling is proposed in order to improve the efficiency of evaluating and optimizing pre-mission plans. To deal with the challenge of multiple transport-aircraft missions, the object-oriented modeling method is utilized. The elements of the mission are decomposed into objects and businesses, And the major mission objects and their important properties are summarized. A complex mission can be broken down into basic business modules such as the ground section and flight section. The business models of loading and fueling services in the ground section are described. The business model of the flight section is composed of an air route and flight profile with the flight equation and the fuel consumption model. The logical relationship of objects and business modules is introduced. The architecture of the simulation system, which includes a database, computation module, graphical user interface (GUI) module, and a result analysis module, is established. A sample case that includes two different plans is provided to verify the model's ability to achieve multi-aircraft composite mission simulation.

• 한국환경과학회지
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• 제19권10호
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• pp.1219-1227
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• 2010

In this study, the sensitivity analysis of bed changes due to the various sediment transport equations have been conducted for 80 km reach of the Lower Nakdong River using the HEC-6 which is one dimensional numerical model. The bed elevation changes according to the different sediment transport formulas were compared and analyzed quantitatively. As a result of the numerical simulation, the final bed elevation calculated by Engelund and Hansen(1967), Ackers and White(1973), and Yang(1979) formulas was similar to one another in configuration. The bed change simulated by Engelund and Hansen(1967) were greatest among them, for example, 5.5 m deposition and 2.9 m erosion for 100 years. Also, in the case of Toffaleti (1969) equation, the maximum bed deposition of 8.04 m after 100 years was induced at the 73 km location upstream of the Nakdong River Estuary Barrage. Meyer-Peter-M$\ddot{u}$ller(1948) and Wilcock(2001) formulas produced the deposition only at the upstream end and there was little bed change in the downstream area. The unreal bed configuration of continuously up and down pattern was simulated by Laursen(1958) transport equation.

• Nuclear Engineering and Technology
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• 제54권9호
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• pp.3347-3352
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• 2022

In 2013, the International Atomic Energy Agency (IAEA) changed the recommended maximum range of the Emergency Planning Zone (EPZ) to 30 km, and the Kori Nuclear Power Plant in Republic of Korea has also expanded the EPZ to 30 km, following the recommendation. As a result, metropolitan cities with a high population density are contained within the EPZ, and evacuating millions of people should be considered if the 30 km range of evacuation is to take place. This study proposes an evacuation plan using buses (public transportation) to transport people outside of the EPZ, quickly and efficiently. To verify the appropriate mode share ratio of buses that can guarantee the right of vulnerable road users and reduce traffic congestion, a model was built simulating the Kori Nuclear Power Plant in Ulsan Metropolitan City. The scenarios were established by changing the mode share ratio of buses and passenger cars by 10%. Considering a large-scale network analysis at the city level, a cell transmission model was applied to calculate the evacuation time in each scenario. The result shows that the optimal mode share ratio of buses is 40%, with a total evacuation time of 132 min, considering feasible bus fleets in Ulsan Metropolitan City.

• 한국항해항만학회지
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• 제31권8호
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• pp.733-739
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• 2007

현재 중국의 경우 산업발전은 매우 빠르게 이루어지고 있으나 아직까지 인프라 시설이 구비되어 있지 않아 수요와 공급의 불균형을 이루고 있다. 그러므로 중국자체로는 매년 넘쳐나는 미주 또는 구주 발 총국동북부 지역의 항공물동량을 모두 처리하기 어려운 실정이며 이는 우리나라가 해공복합운송 거점으로서 위상을 확립할 수 있는 좋은 기회가 될 것이다. 이에 본 연구에서는 해공복합운송과 항공운송의 노선별 시뮬레이션 평가를 통해 경쟁력 수준을 평가하고 향후 화물유치를 위한 나아가야 할 방향 등을 제시하였다. 첫째 향후 해공복합운송의 물량을 확보하기 위해서는 지리적으로 유리할 뿐만 아니라 본 연구의 시뮬레이션 분석에서도 도출되었듯이 중국발 미주착 부분에 더욱 집중적으로 관심을 가지고 비즈니스 모델을 창출하여야 할 것이다. 둘째, 해공복합운송의 주요 요인은 비용보다도 서비스에 의한 인지도 부분이나 전체적으로 걸리는 시간에 의하여 결정되는 것으로 나타났으므로 고객의 니즈에 맞는 서비스를 개발하고 이를 지속적으로 제공하여 해공복합운송에 대한 인지도 향상과 아울러 현재 추진 중인 청도와의 RFS(Road Feeder Service)시스템을 주요 해공복합운송의 출발항인 상해, 위해, 연태지역으로 확대하여 추진할 필요가 있을 것이다.

• 한국압력기기공학회 논문집
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• 제16권1호
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• pp.110-116
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• 2020

As the management plan for domestic spent nuclear fuel is delayed, the storage of the operating nuclear power plant is approaching saturation, and the Kori 1 Unit that has reached its end of operation life is preparing for the dismantling plan. The first stage of dismantling is the transfer of spent nuclear fuel stored in storage at plants. The spent fuel management process leads to temporary storage, interim storage, reprocessing and permanent disposal. In this paper, the technical issues to be considered when transporting spent fuel in this process are summarized. The spent fuels are treated as high-level radioactive waste and strictly managed according to international regulations. A series of integrity tests are performed to demonstrate that spent fuel can be safely stored for decades in a dry environment before being transferred to an intermediate storage facility. The safety of spent fuel transport container must be demonstrated under normal transport conditions and virtual accident conditions. IAEA international standards are commonly applied to the design of transport containers, licensing regulations and transport regulations worldwide. In addition, each country operates a physical protection system to reduce and respond to the threat of radioactive terrorism.

• 한국지반환경공학회 논문집
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• 제15권4호
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• pp.13-27
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• 2014

Catchments soil erosion, one of the most serious problems in the mountainous environment of the world, consists of a complex phenomenon involving the detachment of individual soil particles from the soil mass and their transport, storage and overland flow of rainfall, and infiltration. Sediment size distribution during erosion processes appear to depend on many factors such as rainfall characteristics, vegetation cover, hydraulic flow, soil properties and slope. This study involved laboratory flume experiments carried out under simulated rainfall in a 3.0 m long ${\times}$ 0.8 m wide ${\times}$ 0.7 m deep flume, set at $17^{\circ}$ slope. Five experimental cases, consisting of twelve experiments using three different sediments with two different rainfall conditions, are reported. The experiments consisted of detailed observations of particle size distribution of the out-flow sediment. Sediment water mixture out-flow hydrograph and sediment mass out-flow rate over time, moisture profiles at different points within the soil domain, and seepage outflow were also reported. Moisture profiles, seepage outflow, and movement of overland flow were clearly found to be controlled by water retention function and hydraulic function of the soil. The difference of grain size distribution of original soil bed and the out-flow sediment was found to be insignificant in the cases of uniform sediment used experiments. However, in the cases of non-uniform sediment used experiments the outflow sediment was found to be coarser than the original soil domain. The results indicated that the sediment transport mechanism is the combination of particle segregation, suspension/saltation and rolling along the travel distance.

• International Journal of Railway
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• 제6권2호
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• pp.33-44
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• 2013

In recent years, energy consumption in the transportation sector by expanding motorization continues to increase in almost every country in the world. Moreover, the growth rate of the transportation energy consumption is significantly higher than those of the civilian and industrial sectors. Therefore, every country strives to reduce its dependence on private transport, which is the main contributor to the transportation energy consumption. In many countries, concepts such as Transit Oriented Development (TOD) or New Urbanism, which controls road traffic by increasing the proportion of the public transportation significantly, have been implemented to encourage a modal shift to public transport. However, the level of change required for eliminating environmental problems is a challenging task. Minimizing transportation energy consumption by controlling the increase of the traffic demand and maintaining the level of urban mobility simultaneously is a pressing dilemma for each city. Grasping the impact of the diversity of the urban transport and infrastructure is very important to improve transportation energy efficiency. However, the potential for reducing urban transportation energy consumption has often been ineffectively demonstrated by the diversity of cities. Therefore, the accuracy of evaluating the current efficiency rate of the urban energy consumption is necessary. Nevertheless, quantitative analyses related to the efficiency of transportation energy consumption are scarce, and the research on the current condition of consumption efficiency based on international quantitative analysis is almost nonexistent. On the basis of this background problem definitions, this research first built a database of the transportation energy consumption of private modes in 119 cities, with an attempt to reflect individual travel behaviors calculated by Person Trip data. Subsequently, Data Envelopment Analysis (DEA) was used as an assessment method to evaluate the efficiency of transportation energy consumption by considering the diversity of the urban traffic features in the world cities. Finally, we clarified the current condition of consumption efficiency by attempting to propose a target values for improving transportation energy consumption.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2005년도 춘계학술발표회
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• pp.23-29
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• 2005

우리나라 해운기업은 국제적인 경쟁력 속에서 해운강국으로 발전하기 위해서 정부 및 해운선사가 안전관리의 활성화로 해상에서의 인명보호 및 해양환경의 보호를 위해 가일층 노력하고 있는데 아직까지도 내항선에서의 안전관리에 관한 활성화방안이 미흡하여 내항선에 맞는 체계적이고 현실적인 안전관리 활성화방안이 절실하다. 따라서 본 연구에서는 오늘날 해운기업에서 국제적으로 중요시하는 안전 및 해양환경보호에 중점을 두고서 내항선 안전관리의 성과분석 및 활성화 방안의 개발 방향을 제시하였다.

• 통상정보연구
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• 제15권2호
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• pp.207-232
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• 2013

FTA상의 특혜관세 혜택을 누리기 위해서는 무엇보다도 수출입기업 스스로가 해당 FTA협정상의 원산지 규정 등에 대한 내용을 정확히 이해하고 올바로 활용할 수 있는 능력을 배양하는 것이 중요하다. 또한 FTA는 본질적으로 기업들에게 혜택을 주는 제도이지만 그에 따른 의무와 엄격한 충족을 전제로 하는 것이기 때문에 협정상 선결요건의 정확한 이해와 적용도 중요하다. 본 연구는 한 EU FTA 원산지의정서 제13조에 규정되어 있는 직접운송 요건을 충족하는지의 여부와 관련하여, 최근 관세청에 접수되어 결정이 내려진 심사청구사례를 분석하는 것이다. 이를 위하여 우선 한 EU FTA하에서 원산지규정과 협정관세적용을 위한 직접운송 요건의 적용 법리를 분석을 토대로, 본 사례의 사실관계와 대상결정 및 본건 관련법령과 결정내용을 상세하게 분석한 후, 본 사례가 수출입기업들에게 주는 시사점과 실무상의 대응책 및 제도적 보완방안을 구체적으로 제시하고자 한다. 한편 본 연구는 국내외 학술문헌을 분석도구로 활용하는 문헌분석적 연구방법과 한 EU FTA 협정문의 주요내용을 법리적으로 분석하는 법리적 연구방법을 주로 채택하였다. 이외에 문헌연구의 한계를 극복하고 객관성을 향상시키기 위하여 심사청구되어 관세청이 결정한 최근의 사례를 분석하여 관련분야에 인용하는 사례분석적 연구방법도 병행하였다.

• 방사성폐기물학회지
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• 제17권2호
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• pp.167-181
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• 2019

최근 국내에서 육상 및 해상을 통한 소외 정상운반 시 진동 및 충격하중에 대한 사용후핵연료의 건전성 평가 기술 개발이 수행되고 있다. 이와 관련된 국내 연구사례는 전무하여 기존에 진행된 또는 현재 수행중인 해외연구사례를 조사하여 국내 연구에 참고하고자 한다. 2000년 이전 과거 미국의 사용후핵연료의 정상운반 시 진동 및 충격하중 측정 관련 연구현황을 조사하였고 2009년부터 미국국립연구소 주관으로 실시한 단축가진시험, 콘크리트블럭 트럭운반시험, 다축가진시험에 대해서 조사하였으며 2017년 미국 SNL, 스페인의 ENSA, 한국이 공동으로 수행한 복합운반시험을 상세히 조사하였다. 시험 준비과정, 절차, 가속도 및 변형률 측정결과, 유한요소 및 다물체동역학 해석과정 등이 조사되었다. 각 시험 별로 측정된 변형률 자료를 바탕으로 사용후핵연료 피로곡선과 비교한 결과 손상을 일으키기에는 매우 미미한 정도의 변형률이 발생한다는 초기 결론을 얻었음을 확인하였다. 하지만 현재 결론은 일부 결과만을 검토한 예비 결론으로 상세한 검토가 현재 미국에서 진행 중이다. 미국에서 지금까지 수행한 사용후핵연료의 정상운반조건에서의 진동 및 충격하중 측정과 관련하여 조사된 내용은, 국내 운반환경에서 사용후핵연료의 정상운반시험을 수행할 때 참고할만한 유용한 자료라 판단된다.