• Proceedings of the Membrane Society of Korea Conference
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• 1996.10a
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• pp.82-83
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• 1996

키토산 막을 이용한 유기혼합물 중의 물을 효율적으로 분리해내는 투과증발공정은 많은 발전을 거듭해 왔으며, 특히 에탄올중의 물을 효율적으로 탈수하는 것에는 탁월한 성능을 보고한 바 있다. 키토산은 주로 게등의 갑각류의 외피에서 얻을 수 있는 키닌을 주원료로 하는 물질로서 친수성이 뛰어난 막재료뿐만 아니라 생체적 합성이 요구되는 생체재료로도 널리 사용이 되고 있는 물질이다. 에틸렌즐리콜은 석유화학공정에서 생성되는 에틸렌 옥시이드를 원료로 하여 제조가 되고 있는 물질이다. 에틸렌글리콜은 PET의 원료로서 사용이 많이 되고 있으며, 겨울철에는 자동차등의 부동액이나 눈이 많이 내리는 지역에서 효율적으로 눈을 제거하기 위하여 공항의 활주로등에서 주로 사용이 되고 있는 물질이다. 에틸렌글리콜의 제조공정중에서 물을 효과적으로 제거하는 방법으로는 증류법이 있을 수 있으나 에틸렌글리콜의 비점이 물보다 현저히 높기 때문에, 공비혼합물을 생성하지 않는 이 혼합물의 특성과는 무관하게, 투과증발법을 이용할 경우 에너지의 절감이 이루어지게 되기 때문에 매우 효용적이고 추천할만할 공정이다. 또한 활주로의 부동액등으로 사용되는 경우 에틸렌글리콜의 재활용이 이루어질 경우 경비의 절감이나 환경적인 문제의 해결등의 장점이 있어서 물의 분리가 요구되고 있다. 이 경우에는 마찬가지로 에틸렌글리콜과 물의 분리는 일반적인 분리에 비해서 투과증발법이 유용하다고 할 수 있다. 본 실험에서는 키토산 막의 효율적인 응용예로서 기존의 알콜의 탈수와 더불어서 에틸렌글리콜의 탈수를 고찰해보고자 하였다.관리가 간편하며, 용존산소량을 줄일수 있다는 점에서 장점이 있으나, 전 ultra pure water의 system이 열적으로 안정해야 하고 경제적인 문제가 수반하는 단점을 가지고 있다. 후자의 경우, 미량의 과산화수소수 (1~10,000 ppm)를 이용해 처리 해주는 방법의 경우 경제적으로 큰 장점이 있고, 처리가 단순하다는 장점이 있으나 과산화수소수 자체에 포함하고 있는 높은 impurit level, 그리고 처리후 장시간의 flushing time을 가져야 한다는 단점등이 존재 하고 있다.요구된다. 몰입이 가능하여 임계치가 저하된 것으로 여겨진다. 또한 광학적 이득의 존재는 이 구조에 의한 극단파장 반도체 레이저다이오드의 실현 가능성을 나타내는 것이다.548 mL에 비해 통계학적으로 의의 있게 적었다(p<0.05). 결론: 관상동맥우회로 조성수술에서 전방온혈심정지액을 사용할 때 희석되지 많은 고농도 포타슘은 fliud overload와 수혈을 피하고 delivery kit를 사용하지 않음으로써 효과적이고 만족할 만한 심근보호 효과를 보였다.를 보였다.4주까지에서는 비교적 폐포는 정상적 구조를 유지하면서 부분적으로 소폐동맥 중막의 비후와 간질에 호산구 침윤의 소견이 특징적으로 관찰되었다. 결론: 분리 폐 관류는 정맥주입 방법에 비해 고농도의 cisplatin 투여로 인한 다른 장기에서의 농도 증가 없이 폐 조직에 약 50배 정도의 고농도 cisplatin을 투여할 수 있었으며, 또한 분리 폐 관류 시 cisplatin에 의한 직접적 폐 독성은 발견되지 않았

• Journal of Korean Tunnelling and Underground Space Association
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• v.15 no.5
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• pp.483-496
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• 2013

This paper presents the shield TBM technology in soft ground tunnelling. In order to perform this study, a scale model test was carried out using the developed small scaled shield TBM machine. The various instrumentations were conducted during the simulation of tunnelling. In addition, the ground behavior due to the shield TBM operation parameters was measured during the simulation. Based on the simulation results, the stability of the ground was evaluated and the fundamental shield TBM tunnelling technique in the soft ground was suggested. In conclusion, design's reliability through laboratory small scale model test about Shield-TBM section was obtained, and both the improvement plan for safety during construction and the construction plan for securing airport runway's safety during tunnel passing by Shield-TBM propulsion were suggested.

• Journal of Advanced Navigation Technology
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• v.26 no.6
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• pp.393-403
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• 2022

Various studies suggest that the initial operating form of UAM, which is being presented as a solution to the urban traffic problem, will be similar to VTOL aircraft among current aircraft. In a form similar to determining the direction of the runway where fixed-wing aircraft take off and land, the vertiport where take-off and landing of VTOL aircraft takes place determines the flight direction of departure and arrival in consideration of the direction of the wind. Unlike areas where airports are generally built, in the case of downtown areas, it is expected that the characteristics of wind may continuously change depending on the environment of changing terrain or obstacles such as the construction of new buildings. In this study, long-term actual observation data for reviewing the take-off and landing directions at the city center where the location of the vertiport is expected are compared using a wind speed map, and the characteristics of the ground wind and the possibility of change in the direction of the predominant wind depending on the observation period and observation location confirmed.

• The Korean Journal of Air & Space Law and Policy
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• v.34 no.1
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• pp.159-201
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• 2019

Along with Annex 14 Volume I establishment in 1951 and the set-up of restriction surface around the runway, aeronautical technique and navigation performance achieved dazzling growth, and the safety and precision of navigation greatly improved. However, restrictions on surrounding obstacles are still valid for safe operation of an aircraft. Standards and criteria for securing safety of aircraft operating around and on airport is stated in Annex 11 Air Traffic Services and Annex 14 Aerodrome etc. In particular, Annex 14 Volume I presents the criteria for limiting obstacles around an airport, such as natural obstacles such as trees, mountains and hills to prevent collisions between aircraft and ground obstacles, and artificial obstacles such as buildings and structures. On the other hand, Annex 14 Volume I, in the application of the obstacles limitation surfaces, apply the exception criteria, as it may not be possible to remove obstacles that violate the criteria if the aeronautical study determines that they do not impair the safety and regularity of aircraft operation. Aeronautical study has been applied and implemented in various countries including United States, Canada and Europe etc. accordingly, Korea established and amended some provisions of the Enforcement rules of the Aviation Act and established the Aeronautical study guidelines to approve exceptions. However, because ICAO does not provide specific guidelines on procedures and methods of Aeronautical study, countries conducting aeronautical study have established and applied their own procedures and methods. Reflecting this realistic situation, at the 12th World Navigation Conference and at the 38th General Assembly, the contracting States demanded a reexamination of the criteria for current obstacle limitation surfaces and methods of aeronautical study, and the ICAO dedicated a team of experts to prepare new standard. This study, in line with the movement of international change in obstacle limitation surface and aeronautical study, aims to compare and analyze current domestic and external standards on obstacle limitation and height limits, while looking at methods, procedure and systems for aeronautical study. In addition, expecting that aeronautical study will be used realistically and universally in assessing the impact of obstacles, we would recommend the institutional improvement of the aeronautical study along with the development of quantitative analysis methods using the navigation data in the current aeronautical study.

• The Korean Journal of Air & Space Law and Policy
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• v.31 no.2
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• pp.3-35
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• 2016

The United States Constitution gives power to the federal district courts to hear admiralty cases. 28 U.S.C. §.133, which states that "The district courts shall have original jurisdiction, exclusive of the Courts of the States, of any civil case of admiralty or maritime jurisdiction." However, the determination of whether a case is about admiralty or maritime so that triggers admiralty jurisdiction was not a simple question. Through numerous legal precedents, the courts have drawn a line to clarify the boundary of admiralty cases. This unique jurisdiction is not determined by the mere involvement of a vessel in the case or even by the occurrence of an event on a waterway. As a general rule, a case is within admiralty jurisdiction if it arises from an accident on the navigable waters of the United States (locus test) and involves some aspect of maritime commerce (nexus test). With regarding to the maritime nexus requirement, the US Supreme Court case, Executive Jet Aviation, Inc. v. City of Cleveland, held that federal courts lacked admiralty jurisdiction over an aviation tort claim where a plane during a flight wholly within the US crashed in Lake Erie. Although maritime locus was present, the Court excluded admiralty jurisdiction because the incident was "only fortuitously and incidentally connected to navigable waters" and bore "no relationship to traditional maritime activity." However, this historical case left a milestone question: whether an aircraft disaster occurred on navigable water triggers the admiralty jurisdiction, only for the reason that it was for international transportation? This article is to explore the meaning of admiralty jurisdiction over aviation accidents at US courts. Given that the aircraft engaged in transportation of passenger and goods as the vessels did in the past, the aviation has been linked closely with the traditional maritime activities. From this view, this article reviews a decision delivered by the Seventh Circuit regarding the aviation accident occurred on July 6, 2013 at San Francisco International Airport.

• Journal of Korean Society of Transportation
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• v.24 no.1 s.87
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• pp.19-28
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• 2006

To develop a crisis management for aviation safety, this study has defined crisis management includes risk management which is eliminates or lowers risks prior to accidents and emergency response after the accidents. This study takes a look at different kinds of crisis managements, risk managements and statistical methods of other nations and fields in order to develop a risk management model. Through surveys which have 102 risk factors that include air traffic control, maintenance and airport sectors, the weight of each risk factor was calculated and the probability was divided to develop a model for risk management. The risk management model of this study is conducted using four steps (risk management plan, risk factor identification, weight and probability analysis, decision making) and 4 standards of weight along with 5 standards of probability This study takes a look at Predictions through a quantitative method using a risk index for the risk management model An effective risk management model should have a wide and continuous collection of data and adopt various methods using this model. The crisis management could not be very effective only using a pre-active risk management. So it should also be conducted by using a pro-active response system to protect additional damage and to prevent accidents of the same nature. From the results, the most important points were the establishment of command and control accountabilities, and cooperation of related organizations.