• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.331-334
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• 1998

p형 실리콘 기판위에 100.angs.의 초기 산화막을 성장시킨 후 붕소(B)와 인(P)을 1MeV 이온주입 에너지로 4.dec. tilting하여 붕소의 도즈량은 1*10/녀ㅔ 13/[cm/sup -2/]까지, 인은 1*10/sup 13/[cm/sup -2]로부터 1*10/sup 14/[cm/sup -2/] 까지 변화시키며 이온 주입하였다. 이온주입 후 RTA 로서 열처리 하였으며, 열처리 시간은 10초에서 40초까지,열처리 온도를 1000.deg.C에서 1100.deg.C까지 변화하였다. 이후 기파낸의 불순물의 프로파일 및 미세 결함의 분포를 분석하기 위하여, SIMS, SRP, XTEM 분석을 실시하였고, 이를 monte-carlo 모ㅓ델로서 시뮬레이션하여 비교하였다. SIMS 분석 결과 열처리 온도와 시간이 증가할수록 접합깊이가 증가하였고, 프로파일이 넓어짐을 볼수 있다. SRP 측정에서 붕소는 주해거리 (Rp)값은 1.8.mu.m~1.9.mu.m, 인의 경우는 1.1.mu.m~1.2.mu.m의 주행거리 (Rp) 값이 나타났다. XTEM 분석결과 붕소의 경우 열처리에 전후에도 결함을 볼수 없었고, 인의 경우 열처리 이후에 실리콘 결정내부에 있던 산소(O)와 인(P)우너자의 pinning효과에 의해 전위다이폴을 형성하여 표면근처로 성장함을 볼수 있었다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.3
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• pp.83-88
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• 2020

With developing vehicle and communication technologies, cars can communicate with road-side infrastructures and among other cars. As autonomous driving cars have been developed, the cars are equipped with many sensors and powerful processing units. There are many studies related to provide cloud services to users by using available resources of connected cars. In this paper, we proposed a dynamic task size decision scheme that considers communication environment between a vehicle and a base station as well as available resources while allocating a proper task to each vehicle. Simulation results based on the proposed model show that a vehicle can complete its allocated task when we considers available resources and communication environments.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.4
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• pp.9-16
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• 2015

Quick and safe message transmission is an important research topic of vehicular ad hoc networks (VANET). Most studies assume that the periodic broadcast of beacon-frames between vehicles increases the safety of the driver. In this paper, we propose a medium access control (MAC) protocol and location-based clustering for the VANET to support reliable data transfer. In our proposal, the cluster heade (CH) manage the access and allocate the resources of the node. Our proposal uses simulation to confirm the reduction of the transmission delay and the collision rate of the signal.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.3 s.174
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• pp.718-727
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• 2000

Nowadays, most passenger cars equipped with automatic transmissions use torque converter clutches to reduce fuel consumption, and recently the slip control scheme of torque converter clutches is widely studied for the expansion of the operating region of torque converter clutches and thus for the further improvement of the fuel economy of vehicles. In this study, the analysis of the torque converter clutch system including the line pressure control unit of the automatic transmission and the actuating hydraulic control unit of the torque converter clutch is performed, and a feedforward controller and a fuzzy logic controller for its slip control are proposed. Also, for the slip controller to use the grade resistance information during control, an observer-based grade resistance estimator is designed. The performance of the designed grade resistance estimator and the slip controller is verified by dynamic simulations, and the effect of the torque converter clutch slip control on the fuel economy is examined using a driving cycle simulation.

• Fire Science and Engineering
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• v.25 no.5
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• pp.32-38
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• 2011

Amphibious possible, and good fuel economy, so as leisure and transport has increased the use of hovercraft. Fire started in Korea, the prevalence is increasing in demand as the trend has been increasing steadily. In this paper, the hovercraft's forward and backward direction can be controlled in order to free the reverse bucket control system was developed. Control due to development by promoting the flow of air and turn right, turn left and easy to reverse the life-saving and stable at high speed, etc. has made possible the operation of hovercraft. The controller for the stability and fast response Fuzzy-PID method was used. To prove the validity of the proposed controller in Matlab simulation and the actual delivery at the firehouse, built into a model for the demonstration test was performed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.1B
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• pp.62-70
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• 2000

Intelligent vehicles are equipped with radar sensors for collision avoidance. We present a method of suppressing mutual interference among pulse-type radars, where all the radars are standardized. We developed a method of separating the true self-reflection from the false one by controlling the pulse emission of a radar in anorhogonal ON, OFF pattern. Interference signal identified in OFF-intervals is recorded to indicate the positions of the expected ghosts in ON-intervals. PFA and PM are derived for a radar system with I-Q demodulation scheme, where Gaussian noise alone is Rayleigh-distributed and Gaussian noise plus reflected radar pulse are Rician-distributed. The value of the threshold adaptively updated in order to prevent the deterioration of PM. In the experimental result, PFA decreases by an order of 10,000, when compared with the conventional M of N majority voting method.

• Journal of Energy Engineering
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• v.20 no.4
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• pp.286-291
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• 2011

The hybrid vehicle has a good fuel economy with a electric type braking energy regeneration system. This paper introduced a novel pneumatic type braking energy regeneration system. The novel system use a scroll mechanism which have both compression function and expansion function. While vehicle is decelerating, the scroll machinery, being operated as a scroll compressor, compress a atmospheric air to save the vehicle's kinetic energy and reuse a compressed air which is reserved in a air tank while vehicle is accelerating. In order to analyze fuel improvements by applying braking energy regeneration system to a vehicle, we simulated the rate of braking energy regeneration through CVS-75 mode driving patterns.

• Journal of Sensor Science and Technology
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• v.9 no.5
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• pp.373-379
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• 2000

In this paper, an estimation system of vehicle position and orientation on magnetic lane, which is a parameter of the steering controller for automated lane following is described. To verify that the magnetic dipole model could be applied to a magnetic unit paved in roadway, the analysis of the model is compared with the data of 3-axis magnetic field measured experimentally. The sensor location could be estimated by analysis of the model based on experimental data. For the magnetic lane model merged magnetic unit, the relation of sensor location and magnetic field is acquired experimentally. The proposed estimation of vehicle position and orientation is adopted to automated lane following by computer simulation.

• Proceedings of the KAIS Fall Conference
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• 2011.05a
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• pp.182-185
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• 2011

본 논문에서는 국내 고속철도 차량 즉, 경부고속철도를 운행하는 KTX, KTX산천 그리고 현재 개발중인 HEMU400x을 대상으로 운행속도 및 운행패턴에 따른 열차 소비전력을 분석하였다. 이를 위해, 선로조건을 고려한 차량의 운전속도 조건과 운행시간,소비전력 등을 예측하기 위한 TPS(Train Performance Simulation)프로그램을 이용하였다. 열차운행 시뮬레이션을 수행하기 위해선 차량, 선로, 속도의 기본 데이터를 필요로 한다. 차량에 대한 데이터는 차량의 최고속도, 제동성능, 견인력 등의 기본 성능과 열차편성에 따른 중량, 길이, 동력차량형식, 열차주행저항등에 대한 제원을 요한다. 선로데이터는 운행시간 예측을 대상으로 하는 선로에 대한 거리별 구배 및 선형, 정거장 위치 및 정차시간에 대한 데이터이다. 속도조건은 구배 및 곡선에 대한 선로제한속도로, 선로데이터와 연계하여 각 선로위치별 차량의 제한속도로 이용된다. 본 논문에서는 경부고속철도 구간에서 운행하는 고속차량 3가지를 대상으로 증속에 따른 전력소모량을 비교하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.70.1-70.1
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• 2018

자동차를 포함한 수송기기, 전기 및 전자산업에 있어 경량화, 소형화, 고성능화와 함께 에너지 및 원가절감을 위한 노력이 활발하게 이루어지고 있다. 알루미늄은 신소재 및 고효율 제조공정 개발을 위한 합금설계기술, 용해/주조 기술, 가공기술, 열처리 기술, 시험평가 기술, 시뮬레이션 기술에 대한 전방위적인 연구가 진행되고 있다. 최근 프리미엄 자동차 시장에 고강도 알루미늄을 이용한 휠 시장이 폭발적으로 증가하고 있다. 2010년 전세계 자동차 휠 시장 규모는 56조원으로 알루미늄 휠 시장 규모는 약 19조원으로 점차 증가하고 있으며, CO2 배출 및 연비 증가에 대한 시대적 요구에 의해 수송기기의 경량화 및 주행 성능 향상으로 알루미늄 휠 시장 규모는 해마다 증가하고 있다. 7xxx 계열의 알루미늄 합금을 이용해 PEO (Plasma Electrolytic Oxidation) 혹은 MAO (Micro Arc Oxidation)를 이용해 표면처리를 수행하였다. 표면처리는 Silicate, Vanadate 및 Phosphate 등의 전해액을 선택적으로 사용하였으며, AC 200 ~ 500 V의 전압 조건 범위에서 CV 모드로 전류를 인가하였다. 형성된 표면 산화층은 산화막 두께 분석, 내마모 특성 평가, 염수분무 평가, 전기화학 평가(Potentiodynamic Polarization) 등을 통해 표면 산화층 분석을 진행하였다.