• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2015년도 추계학술대회
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• pp.241-242
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• 2015

According to globalization of world economy on distribution and sales, logistics and transportation parts are play important role. Especially, it important to know and study how to choose right transport route and which is the key factor of route choice model in multimodal transport system. Thus this study aims to consider 4 main factors: cost, delivery time, freight, and logistics service factors additionally dividing into 13 sub factors and object is forwarders between Mongolia and Korean freight transport. The survey is based on AHP through interview with company officials. The paper provides empirical insights about current status of Mongolian forwarders and difference of the important factors between transportation modes. Result shows that time factor is role factor to choose transport route and then cost factors. Additionally, this study shows 2 different route choose factors between air transport and shipping transport forwarders.

• 대한기계학회논문집B
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• 제32권8호
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• pp.604-611
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• 2008

Detailed analysis of NO formation routes and its contributions with strain rate in hydrogen/air flames were numerically investigated. LiG detailed reaction mechanism has been used for calculation, which is compared with experimental data in literature. It shows good agreement with experiment for both temperature and NO mole fraction. Three routes have been found important for NO formation in hydrogen flames. These are the Thermal route, NNH route and $N_2O$ route. Strain rate were varied to discuss the $EI_{NO}$ reduction trend in hydrogen nonpremixed flames, which are analyzed by each NO formation routes. As a result, as the strain rate increase, $EI_{NO}$ decrease sharply until strain rate $100s^{-1}$ and decrease slowly until strain rate $310s^{-1}$ again, after that $EI_{NO}$ keeps nearly constant. It can be identified that $EI_{NO}$ trend with the strain rate is well explained by a combination of variation of production rate of above Thermal, NNH and $N_2O$ route. Also result of Thermal-Mech. that includes only thermal NO reaction is compared with those of Full-Mech. As a result, It can be identified that there was difference between the two results of calculation. It is attributed to result that Thermal-mech did not consider contributions of NNH and $N_2O$ route. From these result, we can conclude that NOx emission characteristics of hydrogen nonpremixed flames should consider contributions of above three routes simultaneously.

• 수산해양교육연구
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• 제26권2호
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• pp.401-420
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• 2014

This study aims to analyze middle school students' systemic thinking to express organic relations between different organ systems about the movement of food and air and teachers' reflective thinking about science teaching through their reflective journals after the lesson of digestion, circulation, respiration and excretion. Firstly, when investigating the moving route of hamburger eaten inside the body, students expressed the names, locations and forms of organs in the digestive system more than those in the circulatory system or the excretory system. When investigating the moving route of a painkiller taken inside the body, students seemed to have more difficulty in expressing the related organ systems than when investigating the moving route of other things, and they mostly drew pictures of organs in the digestive system as done for the moving route of hamburger. However, when investigating the moving route of water drunk inside the body, students mostly described organs in the digestive system but drew more pictures of organs in the excretory system, than when investigating the moving route of other things. When investigating the moving route of air inhaled inside the body, students mostly drew pictures of organs in the respiratory system, but the rate of their drawing pictures of circulatory organs was low. Secondly, this study analyzed one of the teachers' reflective journals, named Mr. Park. According to his journal, students showed different levels of understanding of organ names, depending on their degrees of familiarity with each organ, and in regard to the locations of organs, science teachers mostly aim to achieve learning objectives so much that they often forget to instruct the locations of organs in fact. As for the forms of organs, science teachers mostly spend so much time explaining the functions of organs that they often forget to describe the exact form of each organ.

• Journal of Preventive Medicine and Public Health
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• 제39권1호
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• pp.53-58
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• 2006

Objectives: We wanted to evaluate the main route of exposure to lead and cadmium for the general population in Korea by using multi-route and multi-media exposure assessment Methods: Samples of air at the homes, samples of the food and water and peripheral blood samples were collected from thirty volunteers living in Seoul (the metropolitan area), Yong-in (the suburban area) and Ansan (the industrial area) in 2001. Graphite furnace atomic absorption spectrometric methods were used for the determination of the Pb and Cd levels in the air, food, water and blood samples. Results: The average intake of lead through the air, drinking water and food were $5.06{\mu}g/day\;(26.3%)\;0.002{\mu}g/day\;(0.1%),\;and\;16.4{\mu}g/day\;(73.6%)$, respectively. The average intake of cadmium through the air, drinking water and food were $0.082{\mu}g/day\;(0.9%),\;0.001{\mu}g/day\;(0.007%),\;and\;12.61 {\mu}g/day\;(99.0%)$, respectively. The blood lead level was statistically higher in the male subjects than in the female subjects (3.39 and $2.22{\mu}g/dl$, respectively), and only gender was a significant variable on the multiple regression analysis for blood lead. Conclusions: This study showed that the intake of lead and cadmium through food was the major route of exposure. A policy to reduce the pollutants according to the exposure routes should be established. However, more studies will be needed to support these data for the general population.

• Journal of Information Processing Systems
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• 제6권3호
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• pp.375-384
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• 2010

Trajectory modeling is foundational for 4D-Route modeling, conflict detection and air traffic flow management. This paper proposes a novel algorithm based Vincenty's fomulas for trajectory calculation, combined with the Dijkstra algorithm and Vincenty's formulas. Using flight plan simulations our experimental results show that our method of En-route trajectory calculation exhibits much improved performance in accuracy.

• 한국항해항만학회지
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• 제39권5호
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• pp.409-415
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• 2015

According to the globalization of world economy on distribution and sales, logistics and transportation parts are playing an important role. Especially, they have to decide what is the key factor of route choice model and how to choose the right transport route in multimodal transport system. By considering the key factors in rote choice model for freight forwarders between Mongolia and Korea, this paper propose 4 main factors: Cost, Delivery time, Freight and Logistics service with 13 sub factors. The importance of factors is surveyed base on AHP through interview with freight forwarders. In results, the empirical insights about current status of Mongolian forwarders are provided with different factors between transportation modes. Expecially, the Time factor is a role factor to choose transport route for air transportation forwarders.

• 대한지리학회지
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• 제43권4호
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• pp.544-560
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• 2008

인천국제공항 버스 노선망의 형성과 그 요인을 밝히기 위하여 사회 경제적 관점에서 분석한 결과는 다음과 같다. 수도권과 충청도, 전주 익산을 배후지로 한 김포국제공항의 노선버스는 인천국제공항이 개항되면서 강원도와 광주, 나아가 영남지방의 주요 도시와도 노선이 개설되고 수도권도 노선망이 더욱 확충되었다. 인천국제공항 버스운행은 단독 또는 복수의 사업체가 노선을 개설했는데, 공동운행을 하는 경우는 수익성이 불확실하거나 지역연고의 노선을 확보하기 위함이다. 항공기여객밀도와 버스 편도 운행회수와의 분석에서 강서구를 제외한 서울시와 서울시의 위성도시인 수원 성남 안양 군포 구리 오산시는 운행회수를 감소시키고, 나머지 시 군 구는 운행회수를 증가시켜야 할 것이다. 수도권의 경우 노선버스와 지하철(전철)과의 운임과 최단소요시간을 비교해 보면 노선버스의 운임은 비싸지만 소요시간이 짧고, 또 환승의 불편이 없기 때문에 이용객이 지하철(전철)보다 많이 이용한다고 할 수 있다. 한편 비수도권에서는 남동부 주변지역에 공항이 분포한 지역은 국내항공기가 노선버스보다 우위에 있으나 대구와 공항이 입지하지 않는 지역은 노선버스가 우위를 나타내고 있다는 점이 밝혀졌다.

• 대한임베디드공학회논문지
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• 제9권4호
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• pp.229-235
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• 2014

This paper presents an environmental navigation system which provides a guidance to the users of smart bicycle for a pollution-free route during their travel. The smart bicycle operates as a sensor node being composed of a distributed wireless sensor network over the whole urban area. Several environmental sensors measuring the amount of dust, CO, $CO_2$, $NO_2$ in the air are built into the smart bicycle to estimate the level of air pollution in the located area. Each smart bicycle sends/receives the measured sensor data and the city pollution map to/from the centralized server, which leads the bike-riders to a healthy route by providing the environmental navigation information. The proposed idea and its implementation give a useful insight on various application services with the distributed smart bicycles.

• 한국항행학회논문지
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• 제24권5호
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• pp.348-357
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• 2020

eVTOL PAV의 상용화에 있어 해결해야할 중요한 과제들 중 하나는 도심항공 모빌리티 운용에 따른 소음을 감소시키는 것이다. 따라서 본 논문에서는 우리나라 수도권 행정구역별 인구 분포 데이터를 분석하여 소음에 영향을 받는 인구수가 최소화될 수 있도록 AEDT (aviation environmental design tool) 소프트웨어를 사용하여 소음 우선 경로를 생성하고, 운용 시의 소음 분석을 수행하였다. 또한, 최단 거리 경로 운영 시 소음에 영향을 받는 인구수와 비교하여 소음 우선 경로가 소음 노출을 얼마만큼 감소시킬 수 있는지 분석하였다. eVTOL PAV 개발 회사에서 소음 데이터를 제공하지 않는다는 점을 감안하여 헬리콥터 모델을 사용하여 분석을 진행하였다. 결과적으로 소음 노출량을 최소화한 소음 우선 경로가 타 경로들에 비해 더 효율적임을 증명하였다.

• 한국항행학회논문지
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• 제27권5호
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• pp.561-567
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• 2023

본 연구에서는 유인기 회랑에 적용되는 충돌 위험 모델을 활용하여 UAM (Urban Air Mobility) 회랑의 충돌 위험을 분석하였다. K-UAM 로드맵과 운용개념서에 따르면 UAM은 기존 유인기 운항과 유사하게 지정된 항로를 비행하는 형태를 가지며 출발지와 도착지를 왕복하는 두 가지의 노선으로 운행될 것으로 예상된다. 국내 유인기 노선 중 김포공항-제주공항 간 유인기 운행이 이와 유사하며 두 개의 노선 간 횡 방향 분리간격을 가진 평행항로 형태를 띤다. 본 연구에서는 이와 유사한 형태의 UAM 회랑에 대해 유인기 평행 항로 충돌 위험 분석에 활용되는 충돌 위험 모델을 활용하여 횡 방향 분리간격에 따른 UAM 회랑의 충돌 위험을 분석하였다. 이를 바탕으로 최종적으로 K-UAM 실증 노선을 고려하여 한강 폭 내에 몇 개의 평행 항로가 설치될 수 있는지 분석하였다.