• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.1
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• pp.52-58
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• 2014

To improve the performance of clutch actuator of clutch-by-wire system for commercial vehicles, it is necessary to understand the driving characteristics of the system. To explain and predict the effects of driving characteristics on clutch characteristics, AMESim software is used. The simulation model of clutch-by-wire system is developed in the AMESim environments under the geometrical dimensions and driving mechanisms of the clutch-by-wire system, such as the rotation speed of the DC motor, the gear ratio of the reducer, the design parameters of the release fork, the coefficient of the clutch diaphragm spring, and so on. The results show that the theoretical analysis of the clutch-by-wire system for commercial vehicles using the AMESim software find out the driving characteristics of the clutch actuator, and predict the performance characteristics of the clutch-by-wire system.

• Journal of ILASS-Korea
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• v.19 no.4
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• pp.182-187
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• 2014

As the regulations for Particulate Matter (PM) and Particle Number (PN) emissions from Gasoline Direct Injection (GDI) Vehicle stringent recently, a lot of studies have been made on the emission characteristics of PM and PN. In this study, PM and PN emission characteristics were compared to GDI and Multi Port Injection (MPI) Vehicles using the Condensation Particle Counter (CPC) measurement equipment. And driving mode is divided into normal driving mode (CVS-75, NEDC, NIER 6, NIER 9) and a constant speed driving mode (10 km/h, 35 km/h, 80 km/h, 110 km/h) to evaluate the characteristics in the various operating conditions. In the results, most of the driving mode, PM and PN were emitted from GDI Vehicle more than MPI Vehicle. However, in the constant speed mode of 110 km/h, PM and PN from MPI Vehicle were also a lot of emission. It is determined to cause a difficulty in the fuel injection control of the MPI Vehicle.

• Journal of Korean Society of Transportation
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• v.25 no.2 s.95
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• pp.39-50
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• 2007

This study investigated how drivers' cognitive characteristics, such as perception-motor skills and safety-seeking motivation; personal characteristics, such as sensation-seeking disposition coping with physical and social dangers; their self-perceived driving ability; and their normal driving behaviors influence the number of driving violations. 352 drivers participated in the study. MANOVA was performed in order to test the differences in their driving behaviors according to their level of sensation-seeking disposition and driving ability, and Structural Equation Modeling was used to examine the causal relationships among their demographic characteristics, sensation-seeking dispositions, driving ability, driving behaviors and the number of violations. The results indicated that drivers who had higher perception-motor skills seemed to be careful with pedestrians. From the results, drivers who had somewhat higher safety-seeking motivation tended to violate fewer traffic regulations intentionally or accidentally and showed more positive driving behaviors. Furthermore, drivers who had higher perception-motor skills, higher sensation-seeking disposition, and lower safety-seeking motivation had a tendency to violate intentionally more traffic regulations. The older drivers showed driving behaviors that were careful of pedestrians. The drivers who had higher sensation-seeking disposition and longer driving careers violated more traffic regulations, both intentionally and accidentally. Results from LISREL indicated that the predictive variables directly or indirectly influenced on drivers' violation numbers ($x^2$=341.62(p=.00), GFI=.94. RMR=.10).

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.9
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• pp.1415-1421
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• 2004

In this study, a position synchronous control algorithm applied to two-axes pneumatic cylinder driving apparatus is proposed. The position synchronous control algorithm is composed of position controller and synchronous controller. The position controller is designed to minimize the effect of several nonlinear characteristics peculiar to the pneumatic cylinder driving apparatus on position control performance. The synchronous controller is designed to reduce the synchronous error. The effectiveness of the proposed control algorithm is proved by experimental results.

• Journal of Power System Engineering
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• v.8 no.4
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• pp.24-30
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• 2004

In this study, a position synchronous control algorithm applied to two-axes pneumatic cylinder driving apparatus is proposed. The position synchronous control algorithm is composed of position controller and synchronous controller. The position controller is designed to minimize the effect of several nonlinear characteristics peculiar to the pneumatic cylinder driving apparatus on position control performance. The synchronous controller is designed to reduce the synchronous error. The effectiveness of the proposed controller is proved by simulation results.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.762-767
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• 2004

In this study, a position synchronous control algorithm being applied to two-axes pneumatic cylinder driving apparatus is proposed. The position synchronous control algorithm is composed of position controller and synchronous controller. The position controller is designed to minimize the effect of several nonlinear characteristics of the driving apparatus. The synchronous controller is designed to reduce the synchronous error. The effectiveness of the proposed controller is proved by simulation results.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.1
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• pp.26-33
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• 2009

The directions of the road are divided into two, the right-hand side and left-hand side of the road, by the convention and specific native method in the world. This paper deals with the characteristics and behaviors of drivers who are accustomed to driving on right-hand side of the road, drive with a handle on the left-hand side, and comparing with left-hand side drivers. The driver's eye movements were measured by eye camera and questionnaires were used for measuring subjective evaluation such as driving mental workload. The experimental results indicated even if the experts who had much experience on right-hand side driving, they had lower driving skill than novice driver, accustomed to driving on left-hand side. In terms of mental workload, MCH rating scale and MNASA-TLX, the right-hand side drivers were in lower stress condition than the left-hand side drivers because of having much driving experience. However, they conducted a few mistakes by confusing the position of turn signal and windshield wiper because of their driving habit or traits and it lead to operation mistakes. These results can be applied effectively to develop the driving support information with changed environments.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.9
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• pp.15-22
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• 2013

A new LED lamp driving technology with a charge pump instead of a conventional DC-DC converter is proposed. The proposed driving technology is used to control the LED lamp with digital dimming. The power loss in the zener diodes is reduced because the charging process of the capacitors is selectively controlled according to the digital control signal. From the experimental results, when dimming four LED lamps simultaneously, the average driving circuit efficiency of 89% is obtained, regardless of the dimming level. White light with color temperature over a range of 2800~7200K was produced by dimming control of red, green, blue and amber LED lamps with the proposed driving circuit. The characteristics of the driving circuits can be changed depending on the characteristics of the R, G, B, and A LED lamps. The efficiency of the driving circuits up to a maximum 89% can also be obtained depending on the combination of LED lamps. The driving technology with digital dimming control for LED lamps proposed in this paper would be effective for obtaining high efficiency in LED driving circuits and remote control of LED lamps using digital communications.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.11
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• pp.915-919
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• 2011

We analyzed various forces affective to the charged particles in closed space, to explain the image degradation and lifetime-shortening phenomena because of particle lumping which is one of the serious problems in reflective displays. It is possible to predict the quantity of q/m which is the most important parameter in determining the optical and electrical characteristics, by calculating the image force and kinetic energy. For stable driving, the quantity of q/m must be in the defined range but it changes during the fabrication process, so we added the filtering process to solve this problem and obtained the well-defined nonlinear driving voltage coinciding with the threshold voltage. And we obtained the fully-driving property which prevents the particle lumping and decides the image quality and lifetime of panel from the optical characteristics and occupation surface of moving particles.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.1
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• pp.93-97
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• 2009

We analyzed voltage characteristics of toner particle type display according to particle layers and cell gap between two electrodes and ascertained the aging effects by measuring the response time of particles with and without aging process. The threshold/driving/breakdown voltage is proportional to layers of toner particles and cell gap and the response time at driving voltage is faster than that of threshold and breakdown voltage because of different q/m of color and black particles. The analysis of response time is a method of estimation of optical characteristics, driving voltage and particle lumping and these results are promoted by aging process. We use the laser and photodiode to measure response time and optical properties. It has not been studied and reported to analyze the relationship of response time, threshold/driving/breakdown voltage, lumping phenomena, cell gap, and aging process for toner particle type display.