• 한국군사과학기술학회지
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• 제3권1호
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• pp.66-75
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• 2000

The purpose of this study is to develop and illustrate methods of applying trade-off techniques to landing craft air cushion design evaluation. The problem areas of concern are the application of quantitative analytical methods to conceptual design. The interrelationships between composite system measures and selected performance requirements(speed, cruising range, cargo etc.) are analyzed and the expressions for gross weight are developed as functions of performance parameters. Trade-offs of performance parameters in terms of weight are then calculated. The application of these results to evaluation of Require Operational Capabilities are illustrated.

• 항공우주정책ㆍ법학회지
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• 제25권2호
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• pp.43-77
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• 2010

항공 산업의 발달은 승객과 화물 등의 운송량을 기하급수적으로 증가시켰으며 운송 도중 발생하는 각종 사고에 대한 피해의 규모역시 점차 확대되는 추세이다. 따라서 항공보험의 필요성은 나날이 커져가는 실정이며 대다수의 국가에서 입법으로 강제가입 하도록 하는 경향이 크다. 그러나 우리나라도 가입하였으며, 현재 국제민간항공사회에서 가장 넓게 효력을 발휘하고 있는 1999년 몬트리올 조약과 우리나라의 항공운송사업진흥법 역시 가입하여야 하는 항공보험의 담보범위에 대하여 구체적으로 어느 범위까지를 일컫는지에 대하여 명확한 설명이 없어 논의의 문제를 남겼다. 1999년 몬트리올 조약상 항공보험의 담보범위에 있어 '보험의 형태'는 조약의 목적과 전체적인 맥락에서 볼 때 제3자를 제외한 승객, 수하물, 화물 그리고 지연에 한하는 것이 합당하나, '보상한도액'의 경우는 그 판단이 각국에게 남겨졌다고 할 수 있다. 그러나 1999년 몬트리올 조약과는 달리 이미 EU, 미국, 캐나다와 같은 항공운송사업의 선진국들은 항공보험의 담보범위에 대하여 명확하게 규정하고 있다. 이 국가들은 모두 승객과 제3자에 대하여 항공보험에 가입하여야 함과 그 보상한도액을 법률상으로 규정하고 있다. 또한 EU는 화물과 수하물까지 가입대상에 포함하고 있으며 미국과 캐나다의 경우 화물에 대하여는 보험의 존부여부에 대한 서면고지를 화주에게 제공하도록 함으로 인해 보험가입을 권고하고 있다. 항공보험의 담보범위를 법률상 명확히 하는 것은 항공운송인의 위험분산과 피해자의 충분한 보호 외에도 항공운송에서 요구되는 국제적의무의 준수와 더 나아가 생산적이고 유지 가능한 항공 산업의 발전을 도모하는데 그 이익이 있다. 따라서 우리나라 항공보험에 대한 문제점을 해결하기 위해서는 항공운송의 선진국의 입법례 등을 참작하여 우리나라의 항공운송 실정에 적합한 항공보험의 담보범위를 명시해야함은 물론이거니와 더 나아가 항공보험에 대하여 전체적으로 규율할 수 있는 국내 입법화가 촉진되어야 할 것이다.

• 항공우주시스템공학회지
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• 제15권5호
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• pp.24-32
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• 2021

도심 항공 모빌리티(Urban Air Mobility, UAM)의 핵심 이동수단인 개인 항공기(PAV) 및 화물 운송용 무인항공기(Cargo UAS)는 항공기 시스템의 설계 적합성과 안전성을 동시에 확보해야 한다. 이를 입증하여 형식 증명(인증)을 받으려면 안전성 분석 및 평가를 항공기 개발과정 초기부터 전체 주기에 걸쳐서 체계적으로 수행해야한다. 그러나 안전 필수 항공시스템의 복잡도가 증가하고 최첨단 시스템이 적용됨에 따라 기존의 경험기반, 절차기반의 안전성평가만으로는 항공기 시스템의 안전성을 객관적으로 평하기 어려워졌다. 이러한 문제를 해결하기 위해 국내외적으로 모델링 및 시뮬레이션 기술을 이용한 모델기반 안전성평가(Model-based Safety Assessment, MBSA)가 활발히 연구되고 있다. 본 논문에서는 비행 시뮬레이터와 타겟의 시뮬레이션 모델을 연동한 통합 비행 시뮬레이터를 활용한 모델기반 안전성평가 프레임워크를 제안하였다. 공중충돌방지시스템(Traffic Collision Avoidance System, TCAS) 과 휠 제동 시스템 (Wheel Brake System, WBS) 사례연구를 통해 제안된 프레임워크를 UAM 안전성평가에 적용 가능함을 확인하였다.

• Journal of Radiation Protection and Research
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• 제48권4호
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• pp.167-174
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• 2023

Background: A nondestructive test is commonly used to inspect the surface defects and internal structure of an object without any physical damage. X-rays generated from an electron accelerator or a tube are one of the methods used for nondestructive testing. The high penetration of X-rays through materials with low atomic numbers makes it difficult to discriminate between these materials using X-ray imaging. The interaction characteristics of neutrons with materials can supplement the limitations of X-ray imaging in material discrimination. Materials and Methods: The radiation image acquisition process for air-cargo security inspection equipment using X-rays and neutrons was simulated using a GEometry ANd Tracking (Geant4) simulation toolkit. Radiation images of phantoms composed of 13 materials were obtained, and the R-value, representing the attenuation ratio of neutrons and gamma rays in a material, was calculated from these images. Results and Discussion: The R-values were calculated from the simulated X-ray and neutron images for each phantom and compared with those obtained in the experiments. The R-values obtained from the experiments were higher than those obtained from the simulations. The difference can be due to the following two causes. The first reason is that there are various facilities or equipment in the experimental environment that scatter neutrons, unlike the simulation. The other is the difference in the neutron signal processing. In the simulation, the neutron signal is the sum of the number of neutrons entering the detector. However, in the experiment, the neutron signal was obtained by superimposing the intensities of the neutron signals. Neutron detectors also detect gamma rays, and the neutron signal cannot be clearly distinguished in the process of separating the two types of radiation. Despite these differences, the two results showed similar trends and the viability of using simulation-based radiation images, particularly in the field of security screening. With further research, the simulation-based radiation images can replace ones from experiments and be used in the related fields. Conclusion: The Korea Atomic Energy Research Institute has developed air-cargo security inspection equipment using neutrons and X-rays. Using this equipment, radiation images and R-values for various materials were obtained. The equipment was reconstructed, and the R-values were obtained for 13 materials using the Geant4 simulation toolkit. The R-values calculated by experiment and simulation show similar trends. Therefore, we confirmed the feasibility of using the simulation-based radiation image.

• 한국군사과학기술학회지
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• 제20권3호
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• pp.345-351
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• 2017

A wind tunnel test for the scaled parachute models was performed to verify aerodynamic characteristics for practical usage of Korean low cost low altitude aerial delivery system. The cruciform shaped cargo parachute models for heavy and light weight were ejected into wind tunnel test section; and the drag forces acting on the models in steady condition were measured in accordance with velocity. Also, the maximum opening forces during inflation were obtained and captured by a high speed camera to analyze the inflation characteristics and evaluate the design of the low cost aerial delivery system. The results showed a reliable stability and met the design requirement of delivery operation system for R.O.K Air Force.

• 지역연구
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• 제15권2호
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• pp.39-73
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• 1999

An examination is made of container movements, air cargo/passengers and telecommunications traffic in Northeast Asia during 1995. A drawback to studying flows between major cities is that information on telecommunications traffic is only available between countries. Also container traffic data are restricted to individual ports. Consequently, most attention is paid to movements of passenger aircraft between major cities derived from analysing timetables, particularly as they can be related to regional development concepts applied in Europe such as the 'blue banana' and 'bunches of grapes' concepts. A 'peas in a pod' may be a more appropriate movements are examined again in 1998 to gauge the impact of the Asian crisis.

• Journal of Korea Trade
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• 제26권3호
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• pp.117-136
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• 2022

Purpose - Port is vital for international trade accounting for approximately 80% of world cargo transportation in the global trade sector. Air pollutants emitted owing to the related industry interfaces developed around the port spread throughout the dense population region can have harmful effects on the nearby residents. This study aims to analyze high-concentration diffusion pattern by air pollutants, considering the main management periods by air pollutants. Design/methodology - Employing the concentration criteria per main air pollutant, the analyses of concentration change patterns per air pollutant, wind characteristics that directly affected the air pollutant diffusion, distribution types per air pollutant, and high-concentration diffusion patterns by season according to time changes were conducted. Findings - The substances that caused harmful levels of air pollution in the hinterland living zone of the Busan New Port were PM_10, PM_2.5, and NO_2. Furthermore, the intensive management periods were as follows: For PM_10, 24-h (spring), 12:00-16:00 (summer), 12:00-16:00 (summer), 20:00-12:00 (fall), and 24:00-20:00 (winter), and for PM_2.5, 24-h (all four seasons), and for NO_2, 23:00-04:00 (spring), 23:00-08:00 (summer), and 20:00-08:00 (fall), and 23:00-04:00 (winter). Originality/value - Research finding indicates that regular monitoring and countermeasures to reduce air pollution for each air pollutant makes it possible to achieve effective air quality control in the port and hinterland living zones.

• 한국전산구조공학회논문집
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• 제24권2호
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• pp.193-200
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• 2011

본 연구를 통해 superlite라 불리는 단열 파우더를 채용한 NO96 멤브레인 타입 LNG선 단열 화물창의 만선항해 시 LNG의 BOR(Boil-Off Rate) 예측모델을 제시하였다. LNGCC(LNG Cargo Containment)의 비정상상태 열전달 FEM모델은 만선항해 시 대기 및 해수 조건을 반영하고 복잡한 화물창 단열구조에 균질화 기법을 적용하여 구축하였다. BOR은 만선항해중 LNGCC 내부로 침입하는 총 열량을 이용하여 평가되었으며, 주요 변수에 따른 BOR의 변화는 파라메트릭 열전달해석을 통하여 분석하였다. 그리고 파라메트릭 BOR 특성해석 결과를 토대로 LNG선의 탱크 크기, 단열층의 두께 그리고 superlite의 열전도율을 함수로 하는 BOR 예측모델을 유도하였다. 비선형 과도 열전달해석을 통해 직접 구한 BOR과의 비교를 통해 유도한 예측모델은 최대 1% 이내의 상대오차를 나타내었다.

• 무역상무연구
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• 제28권
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• pp.63-88
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• 2005

Korean government is planning to develop the airport and its surrounding area into a Northeast Hub of Asia. In accordance with the Free Trade Zones Act, Incheon International Airport Corporation is in charge of developing the free trade zone which will be located adjacent to the airport cargo terminals. The free trade zone plays an important part for the promotion of international logistics. So the purpose of this paper is to make research on the activation measures of the airport free trade zone for the building of a hub of international logistics. As for the research, this paper reviews the current regulations of the Free Trade Zones Act. Also this paper analyzes recent plans and reports on the free trade zone by Incheon International Airport Corporation and Korean government authorities. As the results of this paper, it will contribute to the activation of the airport free trade zone, and to building Incheon International Airport into the logistics hub of Northeast Asia, and to the inducement of foreigner's investment in the free trade zone.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.148-153
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• 2008

As the oil price is dramatically jumping up, the consumption of LNG is rapidly expanding and the size of LNG carriers becomes bigger. For LNG ships, the application of DF (Dual-Fuel) engines gradually increases because of high efficiency, which alternatively use diesel or BOG (Boil-Off Gas) from cargo tank as a fuel. The surplus BOG from LNG cargo tank should be exhausted by GCU or liquefied through the BOG reliquefaction system and returned back. This study focused into its operational characteristics through the process simulation using HYSYS and discussed details on the influence of the variations of some operational parameters such as a distribution ratio by the change of fuel mass flow into the DF engine.