• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.263-266
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• 2001

The performance of the powertrain can be analyzed using dynamic models including transient characteristics, and the equations of motion can also be derived from the dynamic models of the powertrain. In this study, the shift transient characteristics of the vehicle equipped with Ravigneaux type planetary gears automatic transmission has been investigated.

• Journal of Technologic Dentistry
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• v.14 no.1
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• pp.133-138
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• 1992

The base of a metal base denture that is made of acrylic resin base and metal in lined by soft liner named silicon rubber and its merits are as follows. 1. It has a good retention and fastness. 2. It has a good comfort and stability. 3. It is easy to mix various kinds of base materials. 4. It is easy to repair. 5. The pressure of bone and mucosal tissue is decreased and bite force is dispersed.

• Journal of computational fluids engineering
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• v.17 no.1
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• pp.36-43
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• 2012

When a high-speed train passes an underground station, large pressure waves are generated due to the piston effect. These pressure waves can cause the problems of vibration and noise as well as the ear discomfort of passengers at the underground station. This work numerically analyzed the pressure wave generation and propagation in an high-speed railway underground station, and the optimal location for vent shafts was studied to improve the passenger comfort by reducing the magnitude of the pressure wave and its rate of change. The evolution of pressure field in the underground station was calculated using a CFD(Computational Fluid Dynamics) software(Fluent), where the axis-symmetric two-dimensional model verified by Wu was used. And this study is applied to modelling of the underground station and the tunnel from Daegok station A-line of GTX(Great Train Express). From the result, we can have a conclusion that the role of vent shafts respectively were different according to the position in and out the underground station. Also Vent shaft in the underground station widely reduced pressure magnitude. And vent shaft out underground station reduced initial pressure peak value. Double vent shafts installed at tunnel toward station entrance and inside of the tunnel are the most efficient to reduce pressure. and pressure reduction increases according to the number of vent shaft.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.222-228
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• 2007

In order to solve the problem of traffic holdups and environmental pollution(contamination), several metropolises are operating the subway and many local government plans hereafter the light rail vehicle operation and it is in the process of preparing. This point of time, it need to evaluate the comfortable characteristic of the seat which is closely connected with passenger and it should be reflected to the product design through the data analysis. The methods of the comfortable characteristic evaluation should be considered to various methods from physical factor to psychological factor. Among these, the most universal and possible quantitative measurement estimate through 'Body pressure measurement system'. From this paper, it was measured the body pressure of the subway seat which is in the process of operating in a domestic and it will be compared and analyzed the material & seat shape, so we evaluated the comfortable characteristic of the short-distance transportation railway vehicle. It was operated the man and woman who belongs in standard shape of Korean, we compared and analyzed the Peak position where the body pressure is visible and body pressure spread out.

• Fashion & Textile Research Journal
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• v.21 no.1
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• pp.67-74
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• 2019

This study aims to investigate the relation between pressure, 3D length change, and subjective pressure sensation in sports brassieres. Seven Korean women in their 20s and 30s were chosen as subjects. In the experiment, the subjects evaluated four types of sports brassieres wherein the lower band was changed. The results of the study were as follows. The pressure according to the measurement position was lower at the front part than at the side and back parts (p<.05), and there was no difference in the pressure according to the brassiere type. It was observed that brassiere C, which had the higher extension band, was elongated more than the other brassieres when worn. In the case of brassiere B, which had a slit in the front center, it was observed that the 3D length of the front part changed very little as the slit spreads, and the back part stretched in a manner similar to those of the other brassieres. Subjective pressure sensation was statistically different only at the front and the side of the lower band. Brassiere B(with a silt) demonstrated the least subjective pressure sensation; the pressure sensation was high when wearing brassieres A and D (p<.05). Brassieres B and C were also preferred for overall comfort. In conclusion, it was observed that the substitution of material and morphological transformation affect subjective sensation.

• Journal of Fashion Business
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• v.3 no.1
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• pp.125-137
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• 1999

The present study aims to reveal the sweating reaction of male adults, focused on athletes. With six subjects (3 athletes and 3 non-athletes) in two different conditions of ambient temperature (I : $25\pm1.0^{\circ}C$, II : $29.5\pm1.0^{\circ}C$), their total sweat rate, local sweat rate, skin temperature, physiological reaction (rectal temperature, blood pressure, and pulse rate), and psychological reaction (thermal, moisture, comfort, and perceptive sweat sensations) were measured. The comparison gave the following results: Total sweating rate was greater in non-athletes, while the two groups had more perspiration in ambience II. Local sweating rate in both ambiences was the greatest in the central breast area (athletes) and the infrascapular area (non-athletes). The mean skin temperature had more changes of increase and decrease in athletes. As to physiological reaction, non-athletes had lower rectal temperature and blood pressure as well as higher pulse rate. As for psychological reaction in Ambience II, the 4 sensations were mostly 'hot', 'humid', 'uncomfortable', and 'sweaty'.

• Tribology and Lubricants
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• v.23 no.5
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• pp.228-233
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• 2007

This paper presents the case studies on the friction related wears of an automotive tire, which is strongly connected to the safety and comfort of a driver during a running of a car. Wear scars of a tire tread are affected by various causes such as an air pressure, a wheel alignment, a driving speed, road conditions, starting and braking habits of a driver. The data were collected from used tires for a replacement at the car service center. Most of the wear problems came from the improper repair and adjustment of revolving components, which cause an unbalanced wear of a tread part of a tire. Thus, the regular checking of a tire radically reduces the wear scars of a tire and may increase a driving safety and a fuel economy of a car and a wear life of a tire.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.10 s.253
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• pp.1276-1283
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• 2006

This study proposes two ESP systems which are designed to enhance the lateral stability of a vehicle. A BESP uses an inner rear wheel braking pressure controller, while a EBESP employs an inner rear wheel and front outer wheel braking pressure controller. The performances of the BESP and EBESP are evaluated for various road conditions and steering inputs. They reduce the slip angle and eliminate variation in the lateral acceleration, which increase the controllability and stability of the vehicle. However EBESP enhances the lateral stability and comfort. A driver model is also developed to control the steer angle input. It shows good performances because the vehicle tracks the desired lane very well.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.5
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• pp.22-27
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• 2022

An integrated front steering system and front brake system (FSFB) is developed to improve the stability and controllability of an SUV. The FSFB simultaneously controls the additional steering angle and front brake pressure. An active front steering system (AFS) and an active front brake system (AFB) are designed for comparison. The results show that the FSFB enhances the lateral stability and controllability regardless of road and running conditions compared to the AFS and AFB. As a result, the yaw rate of the SUV tracks the reference yaw rate, and the side slip angle decreases. In addition, brake pressure control is more effective than steering angle control in improving the stability and steerability of the SUV on a slippery road. However, this deteriorates comfort on dry or wet asphalt.

• Journal of the Korean Society of Clothing and Textiles
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• v.11 no.3 s.25
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• pp.41-55
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• 1987

The purpose of this study is to investigate the effects of napping of knitted fabric on wear sensation and physiological responses. Experimental garments were four types of warm-ups made of either $100\%$ PET or $65/35\%$ P /C and either napped or unnapped respectively. Two healthy young female adults were chosen as subjects for the experiment. Experimental room conditions were as follows: Temp., $22\pm0.5^{\circ}C$ R.H., $54\pm3\%$ and Air Velocity, 0.25m/ sec or 2. 86m/sec. The subjects exercised on bicycle ergometer and rested alternatively for totally 45-min. The results are summarized as follows. 1) With napped Warm-up, chest, back, mean skin temp. and microclimates, i.e., temp., relative humidity and water vapor pressure inside the clothing, were higher than with unnapped warm-up. And there was no difference in pulse rate between napped and unnapped warm-ups. 2) Wear sensations of thermal, humidity, tactile and comfort were 'more hot' and 'more uncomfortable' in 0.25m/sec air velocity. but in 2.86m/sec condition the tactile sensation was 'better' and 'more comfortable' with napped warm-ups. According to Pearson's Correlation, among various kinds of wear sensations, tactile is most related with comfort. From these results, it can be concluded that napped fabric decreases the rate of heat trans? mission and moisture diffusion through the clothing. Therefore skin and body temp. and temp., R.H., Vapor Pressure inside the clothing are increased.