• 한국자동차공학회논문집
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• 제17권3호
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• pp.68-73
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• 2009

The purpose of this study is to assess key competencies, especially mathematical skills and communications skills, in order to find disaccord between industry and college in the field of automotive electricity on technical engineering education. For this study, an assessment sheet is consisted of nine questions items. Four questions items of them are to assess mathematical skills and five questions items of them are to assess communications skills. 134 copies returned assessment sheets are analyzed after data cleaning and it is concluded that disaccord between industry and college in the field of automotive electricity on technical engineering education is found.

• 공학교육연구
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• 제11권3호
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• pp.63-69
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• 2008

본 연구에서는 공학기술교육에서 자동차전장 분야의 프로젝트 수업에 준비 단계, 계획 단계, 실행 단계, 정리 단계로 프로젝트 학습을 진행하였다. 본 연구의 목적은 학습자 관점에서 프로젝트 과목을 이수한 학습자의 인식에 대해 알아보고 이를 통해 보다 나은 프로젝트 수업 방법을 모색하는데 있다. 자동차 전장의 하드웨어와 소프트웨어 분야 28명의 재학생을 대상으로 사전검사와 사후검사를 실시하고 이를 유의도 .05 수준에서 통계처리한 결과 다음과 같은 결론을 얻었다. 프로젝트 수업을 통해 팀활동과 협동심이 고취되고 발표와 관련된 의사소통이 증가하였다. 프로젝트 준비를 제대로 하여 현장을 충실히 반영하였고 프로젝트의 개념을 잘 알게 하여 학습자 관점의 프로젝트를 수행한 결과 많은 효과와 경험을 얻을 수 있었다. 그러나 성취감과 자신감은 기대한 만큼 증가하지 않아 프로젝트 수행의 어려움을 알 수 있었다.

• 환경정책연구
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• 제11권3호
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• pp.97-122
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• 2012

이 논문은 온실가스저감정책으로 인해 에너지가격이 상승될 때, 자동차산업의 생산, 고용, 수출 및 소비에 어떠한 영향이 있는지를 실증적으로 분석하고자 한다. 자동차산업의 경우 생산액과 부가가치는 에너지가격 상승에 따른 충격이 유의적이지 않았다. 자동차산업에서 많이 사용하는 전력가격의 상승도 생산과 부가가치에 부정적 영향을 주지만 유의적이지는 않았다. 고용에 대해서는 전력가격이 유의적으로 부정적 영향을 미치는 것으로 나타났다. 수출 역시 에너지가격이 부정적인 영향을 미치는 것으로 나타나지만 유의적이지는 않았다. 소비의 경우에는 석유가격의 상승이 부정적인 영향을 미치기는 하나 유의적이지는 않았다. 이는 탄소세나 배출권거래제도와 같이 전력가격을 상승시키는 온실가스저감정책은 자동차산업의 고용에 미치는 영향이 부정적임을 시사한다. 특히 자동차산업의 고용 측면에서는 온실가스저감정책에 따른 충격을 완화시키는 정책수단이 추가적으로 요구된다고 할 수 있다.

• 기술사
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• 제34권4호
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• pp.69-73
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• 2001

Due to the rapid increase of automobiles and daily driving distances, air pollution by automobiles is still dominant problem of large city in spite of strict emission refutation and development of reduction technologies. Among the air pollution resources of automobile , industry. electricity generation and heating. automobile keeps 51% of total nationwide air pollution in 1998 and this proportion Is increasing in large cities from 65% to 85%. To reduce these air pollution. catalytic converter and electronic engine control, exhaust gas re-circulation and evaporative emission control system have continuously developed and applied to automobiles since 1987. Also strong emission standards and emission durability warranty have enforced and monitored annually by sampling several vehicle models. But technologies and regulations are incomplete, driver should participate in reducing air pollution for himself by planning driving, avoiding unnecessary idle and air conditioning, keeping periodic maintenance and using mass transportation.

• Advances in Energy Research
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• 제3권3호
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• pp.167-179
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• 2015

This paper presents a techno-economic analysis of a partial repowering scheme for an existing 210 MW coal fired power plant by integrating a gas turbine and by employing waste heat recovery. In this repowering scheme, one of the four operating coal mills is taken out and a new natural gas fired gas turbine (GT) block is considered to be integrated, whose exhaust is fed to the furnace of the existing boiler. Feedwater heating is proposed through the utilization of waste heat of the boiler exhaust gas. From the thermodynamic analysis it is seen that the proposed repowering scheme helps to increase the plant capacity by about 28% and the overall efficiency by 27%. It also results in 21% reduction in the plant heat rate and 29% reduction in the specific $CO_2$ emissions. The economic analysis reveals that the partial repowering scheme is cost effective resulting in a reduction of the unit cost of electricity (UCOE) by 8.4%. The economic analysis further shows that the UCOE of the repowered plant is lower than that of a new green-field power plant of similar capacity.

• 동력기계공학회지
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• 제2권1호
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• pp.80-85
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• 1998

Engineering plastics have been magnified its usability due to its outstanding mechanic al, electrical and chemical properties, for example, in the area of computer, electricity, electronics, automobile, camera industry. In recent, automobile speedometer system is changing from manual operation to motor operation. All plastic gears inserted by metal shaft are used In motor operated speedometer system. Therefore, in this research, experimental investigation of the shrinkage phenomenon was executed according to various inserted depth and injection conditions. In experiments, the inserted depth was controlled as 30% and 90% of the total thickness of the plastic gear. The main parameters of injection process were selected as injection pressure, holding pressure, melt temperature, injection rate. As main results, free shrinkage rate of the test part is increased about 4 times to restricted shrinkage rate and shrinkage phenomenon against all injection conditions have a trivial effect on the test parts as conventional parts.

• International journal of advanced smart convergence
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• 제11권3호
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• pp.206-214
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• 2022

Automobile manufacturers in each country are spurring the development of electric vehicles that use electric energy, an eco-friendly energy, as a futuristic vehicle. Electric vehicles have the advantage of no harmful gas or environmental pollution and low noise. Unlike automobiles using existing internal combustion engines using fossil fuels, electric vehicles use the electricity of batteries to cause rotational motion of motors. In the electric vehicle driven by the motor, it is indispensable to develop a controller for controlling the motor. One of the areas where automobile manufacturers are concentrating is the development of small electric vehicles as a personal transportation means. Small electric vehicles such as electric motorcycles, one-seat electric vehicles and two-seat electric vehicles are expanding the market as a means of operating throughout the city. In the domestic road conditions with many hills, it is effective to have a separate transmission system for small electric vehicles to drive smoothly. In this study, we propose a new type of continuously variable transmission(CVT) system to ensure that small electric vehicles can be driven smoothly in hilly domestic terrain. The proposed CVT system is equipped with a basic disk and a rotational disk in the driving pulley and the driven pulley, respectively, and is applied with a sloping spline to rotate the rotational disk. To commercialize the proposed CVT system, an experimental device was developed to examine the power transmission efficiency and the configuration of the CVT system was proposed.

• 전자공학회논문지 IE
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• 제43권3호
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• pp.22-27
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• 2006

본 논문에서는 새로운 제어방식과 평면 변압기(planar transformer)를 이용한 자동차용 35W급 메탈헬라이드 램프용 고효율 전자식 안정기의 제어시스템을 제안하였다. 본 논문에서는 밝기, 연색성, 광효율, 수명 등에서 기존의 할로겐 램프에 비해 우수한 특성을 가지고 있지만 복잡한 과도특성을 가지고 있는 메탈헬라이드 램프를 자동차에 적용하기 위해 마이크로컨트롤러에 의한 디지털 제어방식을 전자식 안정기에 적용하여 램프 요구조건 및 주변 환경에 최적으로 적용할 수 있도록 전자식 안정기를 설계하였다. 또한, 자동차의 밧데리 입력전압에 따라 안정기 컨버터(Flyback Converter)의 스위칭 주파수를 가변하여 안정기의 효율증대를 도모하였고, 컨버터의 고주파 스위칭 변압기를 평면 형태로 설계하여, 기존의 고주파 변압기에 비해 손실, 무게 등의 절감과 전체적인 크기를 축소하여, 밧데리라는 한정된 에너지와 한정된 공간을 갖는 자동차에서 효율적인 전력제어를 실현하였다. 개발된 안정기에 대한 동작특성을 실험을 통해 확인하였다.

• International journal of advanced smart convergence
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• 제11권3호
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• pp.222-228
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• 2022

As a means to cope with the climate change crisis caused by global warming, automobile manufacturers continue to make efforts to use the driving energy of vehicles as electricity. As a result, parts industry such as battery, motor, and controller are attracting attention. China is often seen in large cities, with electric vehicles such as electric bicycles, electric motorcycles, and small electric vehicles popularized and commercialized, mainly in large cities. However, small electric vehicles are not popular in Korea, which is why the country's topography is high in hills. In order to drive the hilly domestic roads, power performance including vehicle climbing ability should be improved. In order to improve the power performance and the climbing capacity of small electric vehicles, the capacity of the motor should be increased. However, when the performance of the motor is improved, the weight of the motor becomes heavy and the price competitiveness is likely to decrease. In addition, in order to operate a high-performance motor, the power consumption of the battery is rapidly increased, so various problems must be solved. In order to commercialize a small electric vehicle for one or two people who do not emit harmful exhaust gas to the human body in a hilly domestic terrain, it is effective to have a separate transmission system. In this study, we were conducted dynamometer test to produce a continuously variable transmission(CVT) system prototype using a spring that can be applied to a small electric vehicle and to install a CVT system prototype manufactured in a small electric vehicle. The dynamometer test results showed that the maximum speed performance, acceleration performance, and climbing performance were improved.

• 한국전자거래학회지
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• 제6권1호
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• pp.35-53
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• 2001

Electronic catalog is a kind of electronic document to exchange product and service data for B2B or B2C EC(electronic commerce). Up to date a lot of selution/service providers which develop EC systems such as shopping malls, have constructed electronic catalogs. However, they use different contents, formats, and exchange methods without a standardized concept and consistent definition of components. This causes problems that time and cost to develop catalogs are duplicated and data exchange across e-marketplaces is difficult. In order to resolve these problems, standardization works for electronic catalog are carried out inside and outside the country. In this paper, we introduce types of standards concerned with electronic catalog, trends of standardization activities, and domestic standardization activities by industry such as electronics, automobile, shipbuilding, heavy industry, steel, electricity, construction, distribution, biomedical, and textile.