• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.121-124
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• 2014

Many of research on noise reduction techniques have been progressed for the improvement of noise environment in subway train. There are many way to noise reduction techniques in the tunnel, but it has been reported as an alternative to attach sound absorption material on tunnel wall. For this reason sound absorption material has been studied for application of tunnel. The objective of this study is to investigate design parameters on a Helmholtz resonator with built-in sound absorption panel for the reduction of the tunnel noise in the subway. Sound absorption panel composed of the perforated panel with sub-millimeter holes and the airspace backed a rigid wall or between panels. The experiment is performed through the change of number of perforated panel, cross sectional area and the depth of airspace of the sound absorption panel under the normal incidence sound.

• 한국항공운항학회지
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• 제17권3호
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• pp.22-31
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• 2009

In this study, we surveyed the operating status of the Light Sport Aircraft(LSA) in Korea, and reviewed the flight route design for Light Sport Aircraft in Korea.

• Journal of East-Asian Urban History
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• 제3권1호
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• pp.139-160
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• 2021

The verandah was a common feature of Chinese multi-storeyed houses in Southeast Asia and China. This paper argues that while an earlier version of a narrow walkway might have had its origin in Singapore, the building of an extension on the upper floors encroaching the airspace over the road skirting the building was an arrangement allowed by the colonial Hong Kong government in compensation to landlords for space devoted to ventilation. As the introduction of reinforced concrete allowed buildings to become taller, the more attractive it was to developers to incorporate the verandah design.

• 한국항행학회논문지
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• 제19권2호
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• pp.108-115
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• 2015

항공용 다변측정 감시시스템은 비행 중 또는 활주로에서 항공기 위치를 제공하는데 사용된다. 항공용 다변측정 감시시스템에서, 질문기는 감시공역에서 항공기에게 적절한 시나리오로 질문을 수행하는데 사용되는 중요한 송신기이다. 질문기의 핵심기능 중 하나인 위스퍼-샤웃 시퀀스는 침입 항공기가 감시공역으로 진입하는 경우 트래픽 밀도를 제어할 수 있다. 따라서 항공용 다변측정 감시스템에서 항공기 간 충돌 가능성을 감소시키고 진입 항공기에 대해 매우 정확한 위치를 구할 수 있게 한다. 본 논문에서는 기존의 2차 감시레이더와 동일한 Mode A/C 질문과 Mode S 질문을 송신하는 질문기를 설계하였다. 질문기에서 적절하게 제어되는 위스퍼-샤웃 질문 시퀀스로, 다변측정 감시시스템은 다수의 항공기로부터 다중 응답 수신에 의해 야기된 동기가블 및 FRUIT현상을 방지할 수 있다.

• 한국항공운항학회지
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• 제6권1호
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• pp.111-124
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• 1998

In order to research the propriety of selection of 4 potential airport sites after a field investigation is made in JEONJU area, this paper analyzes those sites comparatively considering major factors required by FAA. There are at least 10 factors that should be considered when analyzing potential airport sites : convenience to users, availability of land and land costs, design and layout of the airport, airspace obstructions, engineering factors, social and environmental factors, availability of utilites, atmospheric conditions, hazards, coordination with other airports.

• 항공우주기술
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• 제13권2호
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• pp.185-193
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• 2014

본 논문에서는 계기비행절차 설계 프로그램 개발 과정을 개괄적으로 살펴보고자 한다. 제품의 시장 경쟁력 강화를 위하여 외산 제품에 대하여 조사하고 분석하였다. 개발 요구조건 도출을 위하여 계기비행절차 설계 기준에 대하여 살펴보고, 소프트웨어 프로그램 개발 및 시험평가 과정에 대하여 설명하였다.

• 한국항공운항학회지
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• 제25권4호
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• pp.83-90
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• 2017

Unmanned Aerial Vehicles(UAVs) require collision avoidance capabilities equivalent to the capabilities of manned aircraft to enter the airspace of manned aircraft. In the case of Visual Flight Rules of manned aircraft, collision avoidance is performed by 'See-and-Avoid' of pilots. To obtain those capabilities of UAVs named as 'Sense-and-Avoid', sensor-system-based intruder tracking and collision avoidance methods are required. In this study, a multi-sensor-based tracking, data fusion, and collision avoidance algorithm is designed by using a model-based design tool MATLAB/SIMULINK, and validations of the designed model and code using numerical simulations and processor-in-the-loop simulations are performed.

• 한국소음진동공학회논문집
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• 제19권9호
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• pp.863-869
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• 2009

Acoustic noises generated during motor operation in mechanical system are from electromagnetic, mechanical, aerodynamic and electrical sources. For identification of mechanical noise origins, misalignment, unbalance, fan shape, resonance, and vibration modes have been extensively considered to describe noise behavior. An experiment-based approach as well as a mathematical approach needs to be adopted for a realistic study into noise and vibration of the motor, because motor noise characteristics differ from type to type due to various noise sources. This paper analyzes noise characteristics of a brushless DC motor for air-conditioner fan, and proves that the test motor noise originates from acoustic modes of airspace in the motor. The motor noise sensitivity analysis by design of experiments reveals that the noise characteristics are closely related to switching frequency and frame thickness.

• 태양에너지
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• 제8권1호
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• pp.22-32
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• 1988

It is known that the energy consumption and indoor thermal comfort in residential buildings are affected by the thermal performance of building envelopes. The thermal performance of building envelopes varies with their design methods. In this study, the thermal performance changes by the insulating construction types of exterior walls were analyzed, 1) by varing the thickness of the insulation 2) by varing the location of the insulation 3) by varing the location of the plane airspace The analyzed results are presented and the thermal performance evaluating factors were compared and discussed.

• 항공우주정책ㆍ법학회지
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• 제5권
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• pp.321-384
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• 1993

The paper is to study and analyze the civil aviation industry of China and to present some cooperative and developing models between Korea and China in the fields of civil aviation on the basis of mutul benefit. In this study, civil aviation includes both the air transport industry and aircraft manufacturing industry. As it is not easy and realistic for us to conduct field survey on the civil aviation of China so far, this study has havily depended upon the literature data gathered from the ICAO and other published materials. This study includes the following major contents. 1. The historical development of China civil aviation 2. The present status and future prospect of Civil Aviation Adminstration of China(CAAC) 3. The present status of Chinese aircraft industry 4. Administration of airport and airspace of China 5. Air transport industry of China 6. The design of Korea-China civil aviation cooperation