• 대한기계학회논문집B
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• 제33권12호
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• pp.961-967
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• 2009

A 3-dimensional numerical investigation of a WIG effect vehicle with DUP (direct underside pressurization) is performed to predict aerodynamic characteristics and the static height stability. DUP can considerably reduce take-off speed and minimize the hump drag while the vehicle accelerates on the water to take off. The DUP of the model vehicle, Aircat, consists of a propeller in the middle of the fuselage and an air chamber under the fuselage. The air accelerated by the propeller comes into the camber through the channel in the middle of fuselage and augments lift by changing its dynamic pressure to static pressure dramatically. However, the air accelerated by a propeller produces excessive drag and reduces static height stability.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2000년도 추계학술대회 논문집
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• pp.63-67
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• 2000

Up to this day, Most studies of hydroelasticity are inclined to frequency domain atnlysis. Thos amlysis Q the landing, take-4, and dropping of airaqft on a structure. So, the concern of this prrper is a tra a VLFS subjected to dymmic lazd induced by airplane larndirrg and take-off. To predict added mass, dampr exciting force, the source-dipole distribution method were used The responses are accomplished by Fdoimain analysis method is based on Newmark $\beta$ method to pursuit time step pnzcedure taking advantage function for hvdrodvnumic effects.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.202-205
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• 2011

A rotating propeller of turboprop aircraft gives much effect on the aerodynamic characteristics of wing such as lift, moment and stall. Specially, a rotating propeller changes the lift and moment characteristics when aircrafts are in landing or take-off condition. In the present paper, 3-dimensional Navier-Stokes simulations for the interaction of propeller and wing were carried out. For rotating propeller, unsteady sliding mesh method was used to simulate a relative motion. For the power effect analysis in landing and take off configurations, double slotted flap was also considered and the aerodynamic characteristics were investigated. It was shown that the propeller slipstream enhanced the lift slope including maximum lift and this enhancement was more dominant with high lift device.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2007년도 정기 학술대회 논문집
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• pp.341-345
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• 2007

The objective of this paper is to introduce a project on developing construction method based estimation system. It means a 3D product model based estimation system to effectively and efficiently manage estimation process during the project life-cycle. This paper describes a outline and method for 3D based estimation system. Normally, it is not easy to take-off the quantity from 3D CAD model, because of all different depths of the quantity take off in each design development stage and nation. This study shows how to keep the balance of its depths in each design development stage such as schematic design, detail design, shop drawing, and so forth.

• Journal of Magnetics
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• 제15권1호
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• pp.21-24
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• 2010

A new synthetic method for the formation of uniform $\alpha-Fe_2O_3$ nanoparticles was reported and their magnetic properties were investigated. The sonochemical synthesis and the subsequent take-off technique resulted in spherical shaped $\alpha-Fe_2O_3$ nanoparticles with an average diameter of 60 nm. The temperature- and applied magnetic field-dependent magnetization of the $\alpha-Fe_2O_3$ nanoparticles was explained by the sum of two contributions, i.e., the Morin transition and superparamagnetism, because the critical size for superparamagnetism was within the size variation of the nanoparticles.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2018년도 제58차 하계학술대회논문집 26권2호
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• pp.283-284
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• 2018

최근 4차 산업 혁명의 시대가 시작되면서 IT, 사물 인터넷(IOT), 자율 주행 자동차, 드론 등 많은 분야에 있어서 일상생활의 편리함이 증가 하고 있는 추세이다. 하지만 긴박한 상황 시 사고 현장에 대한 빠른 출동 등과 같은 응급 상황에 필요한 분야의 개발은 제한적이다. 본 과제는 이러한 문제점들을 해결하기 위해 드론과 구급차를 결합하여 수직이착륙이 가능한 구급차를 제작할 것이다. 수직 이착륙이 가능한 구급차를 도입함으로써 도로 위 교통에 대한 문제점과 차로 이동이 어려운 환경에서 보다 빠르게 사고현장에 투입하여 인명 구조와 사고 현장을 수습하여 피해를 감소시키고자 한다.

• 드라이브 ㆍ 컨트롤
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• 제14권1호
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• pp.29-34
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• 2017

This study analyzed a life test method for a power take-off (PTO) gearbox. An engine transfers mechanical power (rotation and torque) to a hydraulic pump through a PTO Gearbox with one input shaft and three output shafts. PTO gear box durability under high loads over long time periods was tested using dynamometers. In order to reflect the rated operating conditions, power must be distributed to each output shaft, and experiments were conducted under various conditions to verify the characteristics of the distributed power. An accelerated life test was designed using speed and torque as acceleration factors. Also, efficiency tests were conducted under various load conditions. Also, a lubrication oil composition analysis was performed to analyze gearbox wear status.

• 전자통신동향분석
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• 제38권3호
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• pp.1-10
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• 2023

In this study, the status of global advanced air mobility (AAM) was investigated to derive information and communications technologies (ICTs) that should be prepared according to directions of domestic AAM development. AAM is an urban air traffic system for moving from city to city by electric vertical take-off and landing or personal aircraft. It is expected to establish a three-dimensional air traffic system that can solve ground traffic congestion caused by the rapid global urbanization. With the full-scale commercialization of AAM solutions, high-density air traffic is expected, and with the advent of the personal air vehicle (PAV), the flight space usage is expected to expand. Therefore, it is necessary to develop a safe AAM service through early research on core ICTs for autonomous flight.

• 항공우주시스템공학회지
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• 제17권5호
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• pp.11-18
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• 2023

The architecture of the Fuel Thermal Management System (FTMS) in a commercial aircraft engine was built to model and simulate the fuel system. The study shows the thermal interactions between the fuel and engine lubrication oil through the mission profile of a high bypass ratio, two-spool turbofan engine. Fuel temperature was monitored as it flowed through each sub-component of the fuel system during the mission. The heat load in the fuel system strongly depended on the fuel flow rate, and was significantly increased for the periods of cruise and descent with decrease of fuel flow rate, rather than for the periods of take-off. Due to the thermal interaction in the pump housing, the fuel temperature at the outlet of the low-pressure pump was increased (4.0, 9.2, and 30.0) % over the case without thermal interaction for take-off, cruise, and descent, respectively.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 추계학술대회
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• pp.198-201
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• 2015

아두이노와 압력센서를 이용하여 현대인의 관심사인 건강관리 프로그램을 만드는 것이 목적이다. 현재 한국에는 총 420만명의 요실금 환자가 있을 것으로 추정된다. Information Technology와 Bio Technology의 융합을 통해 이러한 환자들이 쉽고 간단하며 가장 효과적인 골반저근운동(이하 케겔운동) 을 할 수 있도록 유도하여 요실금, 발기부전 등을 치료, 예방한다. 현재 시중에 판매되는 케겔 의료기기는 전기적 자극을 강제로 주어 운동을 해야 하는 시스템으로 하의를 탈의하고 폐쇄된 공간에서 Femcon Therapy를 주로 사용 하였으며 이는 시간제약, 공간제약, 위생적인 제약 등의 문제가 있다. 본 연구는 이러한 제약에서 벗어나 하의를 탈의하지 않고 공간과 위생의 제약에서 벗어나 BT와 IT를 융합한 케겔(Kegel) 의료기를 설계 하였다.