• 제목/요약/키워드: Automobile engineering

검색결과 2,172건 처리시간 0.036초

전기화학적 방법으로 수소장입시킨 자동차 강판재의 수소 영향 (The Effect of Hydrogen in Automobile High Strength Steel Sheets Charged with Hydrogen by Using Electrochemical Method)

  • 박재우;강계명
    • 한국표면공학회지
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    • 제45권5호
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    • pp.212-217
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    • 2012
  • High strength steel sheets used for automobile outer-panels have been intensively studied for developing a lightweight automobile under a strong pressure of the requirements for enhancing the mileage and energy saving in production of automobile parts. It is known that high strength steels are susceptible to hydrogen embrittlement, The susceptibility to hydrogen embrittlement increases with increasing its strength. However, the effect of hydrogen on the fracture behavior of high strength steels, though investigated extensively, has not been fully understood. In this paper, hydrogen was charged with 590DP steels by electrochemical method and its content was measured by hydrogen determinator with the different charging conditions. It was shown that the SP energy and maximum load decreased with increasing charging time. The results of SEM-fractography investigation for the hydrogen contained samples showed that a small portion of dimples on cleavage-fractured surface were observed and the size of the dimples were decreased with increasing hydrogen charging time.

중국 자동차 산업의 기술혁신, 성장전략 및 산업정책의 시사점 (Implication from Technology Innovation, Growth Strategy and Industrial Policy of Chinese Automobile Industry)

  • 백서인;이성민;장현준
    • 지식경영연구
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    • 제17권2호
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    • pp.75-101
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    • 2016
  • Since 2009, China has become biggest automobile supplier and consumer all over the world. Chinese government and automobile firms have been executed strategic and aggressive industry policy and business strategy for nurturing automobile industry as a core manufacturing industry. However, can we assure that all of these policy and strategy have positive effect on Chinese automobile industry? For fulfilling this gab, our research examined the government policy and firm's strategy in different development stage of Chinese automobile industry. According to research result, at initial stage(1983-1996), Chinese automobile industry has grown by technological learning and reverse engineering from Soviet Union, Japan and Germany. In rapid growing stage(1996-2009), Chinese automobile firms have succeed to develop and produce own brand product with 100% own technology. And this kind of quantum jump in technology development was conducted by joint venture policy and M&A strategy. However, at the fourth stage(2010-), Chinese government and firms have over invested and focused on Electric Vehicle manufacturing without developing core technology or SW. Overall, the old-fashioned policy and strategy module in manufacturing industry of China could have negative effect on its industry development.

하중모델을 이용한 자동차 운동 분석과 자율 예측 시스템 알고리즘 (Predictive Algorithm of Self-Control System using Load Control Model applied to Automobile Dynamic)

  • 왕현민;우광준
    • 전자공학회논문지SC
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    • 제47권4호
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    • pp.61-68
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    • 2010
  • 최첨단 항공 기술을 3차원 공간이 아닌 평면에서 움직이는 자동차에 적용하므로써, 미래자동차의 가장 큰 목표인 "안전성"을 크게 향상시킬 수 있으며, 무인 자율 자동차 개발에 한발 더 다가갈 수 있다. 이것은 디지털 비행제어시스템에서 항공기의 운동 역학 모델이 구현되어, 자율 비행이 가능하도록 제어값이 찾아지므로 이루어진다. 이러한 첨단 항공 기술을 평면상에서 운동하는 자동차에 적용한다면, 무인 항공기와 같이 자율 운행할 수 있도록 제어 될 수 있을 것이다. 본 논문에서는 첨단 항공기의 비행 제어 시스템 모델로 사용되는 하중 제어 모델을 자동차에 적용하여 자동차의 운동 역학을 재해석하고, 하중제어 모델에서 자동차 움직임에 따른 승차감 분석을 한다. 또한 승차감 상향을 위한 해결 방법을 제시한다. 그리고 자동차의 자율 주행, 차선 변경 및 지능형 제동 시스템을 구현하기 위한 하중 제어 모델의 사용 예를 제시한다.

USING LOW-VOLTAGE-HIGH-FREQUENCY ELECTRIC FIELD TO MITIGATE MINERAL FOULING IN A HEAT EXCHANGER

  • ;;;;조영이
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회B
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    • pp.2315-2320
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    • 2007
  • This paper presents an investigative study on the efficacy of a new physical water treatment (PWT) technology using an oscillating electric field to mitigate mineral fouling in heat exchangers. Parallel graphite electrode plates immersed in water were used to generate the electric field directly in water. Artificial hard water at 500 ppm hardness was used in all fouling tests. The inlet temperatures were maintained at 23.5${\pm}$0.5$^{\circ}C$ and 85${\pm}$0.5$^{\circ}C$ for cold and hot water sides, respectively. The results at a cold water-side velocity of 0.3 m/s showed a 16-60% drop in fouling resistances from the baseline test depending on the frequency of the electric field for the PWT-treated cases.

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THICKNESS OPTIMIZATION OF AN AUTOMOBILE BODY FOR NATURAL FREQUENCY MAXIMIZATION

  • Panganiban, Henry;Jang, Gang-Won;Chung, Tae-Jin;Choi, Young-Min
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회A
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    • pp.572-577
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    • 2007
  • The paper presents design optimization of an automobile body for dynamic stiffness improvement. The thicknesses of plates making-up the monocoque body of an automobile were employed as design variables for optimization and the objective was to increase the first torsional and bending natural frequencies. By allotting one design variable to each plate of the body, compared to previous works based on element-wise design variables, design space of optimization was reduced to a large extent and numerical instabilities such as checkerboard pattern was efficiently evaded. The method resulted to a considerable amount of increase in the automobile body's torsional and bending natural frequencies. Considering manufacturability of the optimized result, the converged values of plate thicknesses were approximated to commercially-available values by appropriately reflecting their design sensitivities.

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Binary CDMA 기반 차량용 카메라 시스템의 무선 영상전송기 개발 (Development of a Wireless Video Transmitter for Automobile Camera System based on the Binary-CDMA Technology)

  • 최재원
    • 한국정보통신학회논문지
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    • 제18권7호
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    • pp.1571-1578
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    • 2014
  • Binary CDMA는 음성 영상 등의 멀티미디어 데이터를 초고속으로 우수한 전송품질로 통신할 수 있는 우리나라가 개발한 새로운 표준 무선통신 기술이다. 본 논문에서는 유선의 제약 없이 자유롭게 설치 가능한 차량용 무선 카메라 시스템의 개발을 위해 이의 핵심 장치인 Binary CDMA 무선 영상전송기와 중계기의 설계와 구현에 관해 연구하였다.

한국형 고유모델 승용차 정책의 기적 -천부신조의 우리나라 자동차 산업- (Successful implimentation of the new automobile industry policy for korean model cars.)

  • Kim, Z.Q.
    • 한국정밀공학회지
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    • 제13권3호
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    • pp.26-30
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    • 1996
  • The successful development of the automobile industry in Korea is the firstfruit of the epochmaking automobile policy in 1973: Top-Down mass production of Korean model cars. In Top-Down system, indigenous model, which is the most important and difficult part of the automobile industry, is devised first, followed by the mass production of the major parts, such as bodies, engines, etc. This system is in contrast to the prevailing Bottom-up system in the third-world, which assembles automobiles by gradually adding up simple domestic parts. The Government, faced with a vicious circle of depen- dence on assembly of foreign cars, high prices, small demand and low production, decided it was time to move to the mass production of the indigenous models. It was hoped that the efficiencies of low cost Korean models would be epochally improved by overcoming the sway of foreign models and by strengthening the production capabilities of the main parts. In contrast to these develop- ment planning, assembled vehicles numbered only 26,300 units in 1973. In the year of 1995, the total number of automobile production have already passed 2,534,000. As steady growth in worldwide demand is forecast, Korea will able to play a major role as an important automobile maker of the next century.

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한.중.일 자동차 산업의 현황 및 경제협력 (The Present Condition of Korea, China and Japan in Automobile Industry & the Economic Cooperation)

  • 김동기;신용하
    • 산업경영시스템학회지
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    • 제26권3호
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    • pp.10-17
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    • 2003
  • Under the sudden change of competitive environment, the economic cooperation as a part of survival strategy is being a big issue among countries. There was much discussion based on the geological adjacency as well as cultural homogeneity regarding the economic cooperation of three countries, Korea, China, Japan. It has been also known that major trade countries of the world concluded the treaty of region trade, then extended the number of export, and drew a success in foreign direct investment. It can be considered that Korea will play a major role in the three countries' automobile industry based on Japanese demonstrated technology, Chinese resources, market and experience with their economic cooperation. Therefore it is expected that a big result will be achieved throughout such a role play of each country. This paper has a purpose to light up the distinctive quality and the present condition of each country in automobile industry, and to promote the foundation of three countries' economic cooperation. It is convinced that the economic cooperation of three countries, Korea, China and Japan in automobile industry, will play a great role in the world automobile market.

다단계 신경 회로망을 이용한 블랙박스 영상용 차량 번호판 인식 알고리즘 (A License Plate Recognition Algorithm using Multi-Stage Neural Network for Automobile Black-Box Image)

  • 김진영;허서원;임종태
    • 한국정보통신학회논문지
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    • 제22권1호
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    • pp.40-48
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    • 2018
  • 본 논문은 차량과 함께 카메라의 위치가 이동하는 블랙박스 영상을 위한 차량 번호판 인식 알고리즘을 제안한다. 카메라의 흔들림이나 빛의 변화가 많은 블랙박스 영상에서 다단계 신경 회로망을 사용하여 한글 문자의 인식률을 높여 전체적인 차량 번호판의 인식률을 높이고자 한다. 제안한 알고리즘은 차량 번호판의 한글 문자의 모음과 자음을 분리하여 인식한다. 먼저, 1차 신경 회로망으로 모음을 인식하고, 종모음('ㅏ','ㅓ')과 횡모음('ㅗ','ㅜ')로 구분한 뒤 각각의 모음군에 2차 신경 신경회로망을 이용하여 자음을 구분한다. 실제 블랙박스 영상을 획득하여 차량 번호판 인식 시뮬레이션을 수행하였으며, 그 결과 제안한 인식 시스템이 기존의 신경 회로망 기법을 사용한 차량 번호판 인식 시스템보다 높은 인식률을 보임을 확인하였다.