• Journal of Biosystems Engineering
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• 제18권4호
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• pp.305-316
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• 1993

Fuel efficiency in tractor operations dep6nds on the selection of transmission gears and upon the engine being operated at or near maximum torque much of time. The objective of this study was to develop automatic control systems for tractor transmission ratio and governor setting so that the engine is operated at or near maximum torque as much of time as possible. An indoor test unit, which can be used to simulate tractor operation, was built in order to investigate the system design parameters and test the performance of the control system designed. The test-unit consists of engine, gear-type transmission, dynamometer, and control systems for transmission ratio and engine speed. Governor setting lever was controlled by a step motor, and the clutch and transmission levers were controlled by hydraulic cylinders and solenoid valves. The control systems showed good time responses which are assumed to be suitable for optimal tractor operation. The time required for shifting gears from clutch disengagement to engagement was about 1 second, which is almost the same as that for manual shift. And the settling time for engine speed control system was about 5 to 6 seconds.

• 한국지능시스템학회논문지
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• 제11권8호
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• pp.709-714
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• 2001

최근 차량의 경우 미리 설정된 쉬프트 패턴에 의해 변속되도록 고안된 자동변속기가 장착되어 있다. 자동변속기는 기존에 운전자가 수동으로 조작하는 방식과 달리, 자동으로 변속되므로 편안하고 편리하지만, 고정된 패턴을 이용해 변속하기 때문에 운전자의 의지를 반영하지 못한다. 운전자의 의지를 반영하기 위해서는 운전자의 성향뿐만 아니라, 차량의 상태도 같이고려해야한다. 이에, 차량의 상태와 운전자의 조작상태를 모듈 화시켜 학습하여 종합적인 운전성향을 판단하고, 반영하여 변속을 결정하고자 한다. 본 논문에서는 모듈화된 신경망을 이용한 운전의지 판단 알고리즘을 자동차의 자동변속기에 적용하여, 기존에 운전자마다 동일하게 적용되던 고정된 패턴에 의해 변속되던 결과와 비교해 봄으로서, 운전자마다 다른 유동적인 운전의지를 반영한 결과가 우수함을 보이고자 한다.

• 한국자동차공학회논문집
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• 제9권5호
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• pp.105-114
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• 2001

In this study, a shift control algorithm far improving the shift quality of a parallel hybrid drivetrain with an automated manual transmission (AM) is proposed. The general AMT requires the sophisticated control of clutch in the clutch engagement to improve its shift characteristics, and that is generally known to be difficult. But in this hybrid drivetrain, we can control the speeds of clutch plates by engine and motor control, and it provides the easier clutch control in shift process than general AMT. Additionally, it permits the much-reduced shift shock. The motor control during the shift period is also to achieve reduced velocity drop of the vehicle in comparison with that of a general AMT. Furthermore various dynamometer-based experiments are carried out to prove the validity of the proposed shift control algorithm.

• 한국자동차공학회논문집
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• 제21권5호
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• pp.34-39
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• 2013

The gear shifting timing of a manual transmission vehicle is influencing fuel economy. This paper focuses on an gear shifting indicator of an city bus with manual transmission, which can improve fuel economy. The shift indicator is supposed to collect the vehicle data during driving, calculate and compare fuel economy with and without gear shifting, and indicate the proper gear shifting timing. The H/W and S/W of the shift indicator are developed and tested on city bus in this research. The experiments are carried out on real road by 3 different drivers and the results show the improvement of fuel economy from 6.0% to 21.4%. The average engine torque and speed are reduced due to early gear shifting and the usage of highest gear is increased. The results of chassis test are also performed and show 7.5% improvement of fuel economy.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 추계학술대회
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• pp.670-671
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• 2016

자동화 수동변속기는 수동변속기에 액츄에이터를 설치하여 자동으로 수동변속기를 변속할 수 있게 한 변속기로써, 자동화 수동변속기의 조작 편의성과 수동변속기 수준의 높은 연비로 인해 대형 상용차에 많이 적용되고 있다. 대형 상용차에 적용되는 12단 자동화 수동변속기는 다른 자동 변속기와 마찬가지로 자동변속로직과 변속맵에 의해 변속시점을 결정하지만 기존의 방식으로는 변속충격, 클러치 마모, 연비저하 등의 문제점이 발생할 수 있다. 본 논문은 12단 자동화 수동변속기에 알맞은 변속로직 및 변속맵의 설계와 성능확인시험에 대한 내용을 다루고 있다.

• 한국자동차공학회논문집
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• 제12권4호
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• pp.119-128
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• 2004

With the growing traffic density and increasing comfort requirements, the automation of the drive train will gain importance in vehicles. The automatic clutch actuation relieves the drivers especially in urban driving and stop-and-go traffic conditions. This paper describes the dynamic modeling of a clutch actuator and clutch spring. The dynamic model of the clutch system is developed using MATLAB/Simulink, and evaluated by experimental data using a test rig. This performance simulator is useful to develop the clutch-by-wire (CBW) system for an automated manual transmission (AMT). The electro-mechanical type CBW system is also implemented as an automatic clutch for AMT. The prototype of CBW system is designed and implemented systematically, which is composed of an electric motor, worm gear and slider-crank mechanism. The test rig is developed to perform the basic function test of the automatic clutch, and the developed prototype is validated by the experimental data on the test rig.

• 한국정보통신학회논문지
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• 제7권4호
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• pp.623-629
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• 2003

본 논문은 CATV 망 관련 장치 구현에 관한 것으로 기존의 수동형 장치의 비효율성을 제거하기 위해 자동화된 집중식 Headend 시스템 및 분배장치를 구현하였다. 이를 위해 기존의 주파수대역 중에서 비디오 신호의 송신에 사용되지 않은 대역을 확보하고 이를 제어신호의 송ㆍ수신이 이루어지는 제어대역으로 사용하는 송수신 시스템 및 자동화 분배기를 설계하였으며, 상ㆍ하향통신 및 하향통신방식이 공유된 형태로 RS-232를 이용한 9600bps의 CATV 망을 위한 통합관리 시스템을 구현하였다.

• 한국정밀공학회지
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• 제27권3호
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• pp.118-126
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• 2010

The automated mechanical transmission(AMT) is composed of electronic control management(ECM) and automatic shift gear(ASG). The AMT has advantages which are high efficiency of manual transmissions(MT) and offer operation convenience similar to automatic transmissions(AT). However, it has defects that are the torque gap during gear shift transients and shift time is long. To reduce such defects, it is necessary practically to evaluate error and characteristics as developing simulation model before the control algorithm is applied. In this paper, models are composed of vehicle model and AMT shift control model. Particularly AMT shift control model consists of main clutch management model (MCM) and shift control management model(SCM). The developed models were verified by comparing the simulated and experimental results under the same operational conditions. It can also be used to evaluate shift algorithm.

• 드라이브 ㆍ 컨트롤
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• 제10권4호
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• pp.7-13
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• 2013

A tractor is a farm vehicle that is designed to provide a high tractive effort at low speed. It is used for versatile agricultural tasks such as hauling a trailer, tillage, mowing and construction work. As the intensity of work increases, tractors equipped with automatic transmission become popular due to the work convenience. Though manual and power shuttle transmissions are produced by domestic corporations, development for full-automatic power shift transmissions has never been challenged, and so related technology level is quite low. This paper gives a survey of the automatic transmissions from advanced foreign company, which includes layout of gear train, the way hydraulics controls clutches and brakes, electronic control system. The results are expected to be utilized as a basis in the development of original power train design for tractor.

• 감성과학
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• 제4권1호
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• pp.53-60
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• 2001

As a part of HMS(Human-Machine System), the car is very important thing in common life. It is also a significant part to study on the controllers of car that is intentively related with all sensibilities during driving. There are lots of controllers on seating buck of the car. However, there are few study on the sensibility analysis of them. Most of all, the foot controller could be easily overlooked because it could be invisible. This study was based on relationship that the controllers fitted to the driving posture in the drivers' sensibility difference of two transmission modes, automatic and manual transmission. The results show the driver's preference driving posture and sensibility in two kinds of transmission cars. Consequently, it should be designed the seating buck for two different types respectively to be taken comfort driving posture and improve the safety for drivers. Also, it could reduce the fatigue and discomfort in the task of driving. The design of the controllers strongly effects on the drivers' response time. hereby this study was accessed to the sensibility of Korean with analyzing the relationship, quantitative data, and sensibility difference between two kinds of transmission cars.