• Journal of Advanced Navigation Technology
• /
• v.18 no.4
• /
• pp.364-370
• /
• 2014

In this paper, high reliable trench formation technique and a novel fabrication techniques for trench gate MOSFET is proposed which is a key to expend application of power MOSFET in the future. Trench structure has been employed device to improve Ron characteristics by shrinkage cell pitch size in DMOSFET and to isolate power device part from another CMOS device part in some power integrated circuit. A new process method for fabricating very high density trench MOSFETs using mask layers with oxide spacers and self-align technique is realized. This technique reduces the process steps, trench width and source and p=body region with a resulting increase in cell density and current driving capability and decrease in on resistance.

• Proceedings of the KOSOMBE Conference
• /
• v.1996 no.11
• /
• pp.161-164
• /
• 1996

An actively-shielded $r^{2}$-gradient coil has been developed for brain localized MRI or MRS. Spatial localization is very useful for spatial volume selection in MRI or MR Spectroscopy(MRS). The radial(or $R^{2}-$) gradient coil is useful in reducing the artifact or in improving the SNR by selecting the volume with less number of RF pulses. It is, however, difficult to implement the coil with a gradient intensity strong enough to use it for practical whole-body MRI system. For example, the smallest volume size for selection is just 6 cm in diameter with a 250 Ampere of current driving for a whole-body system (in case of 70-cm-diameter). In this study, an asymetric $r^{2}$-coil with a small diameter of 35 cm has been designed and implemented for brain localized MRI or MRS. An 8-rod high-pass-type birdcage RF coil has also been implemented. The coil set has been developed for 1.0 Tesla Medison MRI system and its performance has been verified experimentally.

• Journal of Korean Vacuum Science & Technology
• /
• v.4 no.4
• /
• pp.93-96
• /
• 2000

Microchannel plates (MCPs) have been developed by introducing new materials and process technologies. Main body was made of alumina by programmable punching, laminating, and firing. The channel walls of pore arrays of an MCP were deposited with thin films by electroless copper plating and sol-gel process. Our MCP has advantages such as easy fabrication, durability, high temperature endurance, and applicability to the large size comparing with the conventional MCPs. Experiments on the brightness of an MCP incorporated FED revealed that the FED with a MCP is three to four times brighter than a conventional FED. Moreover, the focusing in a FED is improved. Incorporating an MCP into a FED is one of promising methods to enhance the characteristics of the FED. In addition, amplification yield of the MCP is measured for varying the aspect ratio and the input current.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.27 no.2
• /
• pp.270-276
• /
• 2003

Methodology was suggested to analyze breast volume, base area of breast bulk. and surface area of breast using the 3D measurement system. Thirty-seven middle-aged (30s-40s) women wearing 80A brassiere were participated in this study. Image of the upper body was captured by Phase-shifting moire. The posture of the subject was adjusted to get the full image of the right breast. Rapidform 2001 was used for the analysis of the images. The mean breast volume was 547.0㎤ and mean base area of breast bulk was 235. I$\textrm{cm}^2$ It was also found that the volume(r=0.169) and surface area of breast(r=10.242) were loosely correlated with the circumference difference between top and under breast. Therefore, it is noted that current selection criterion of cup size based on the difference in the two kinds of breast circumference is inadequate. The result of this study is expected to contribute to the design of ergonomic brassiere as well as surgical operations in the medical field.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.22 no.12
• /
• pp.1220-1226
• /
• 2012

This paper proposes a novel type of tactile device utilizing magnetorheological(MR) fluid which can be applicable for haptic master of minimally invasive surgery(MIS) robotic system. The salient feature of the controllability of rheological properties by the intensity of the magnetic field(or current) makes this potential candidate of the tactile device. As a first step, an appropriate size of the tactile device is designed and manufactured via magnetic analysis. Secondly, in order to determine proper input magnetic field the repulsive forces of the real body parts such as hand and neck are measured. Subsequently, the repulsive forces of the tactile device are measured by dividing 5 areas. The final step of this work is to obtain desired force in real implementation. Thus, in order to demonstrate this goal a neuro-fuzzy logic is applied to get the desired repulsive force and the error between the desired and actual force is evaluated.

• Environmental Analysis Health and Toxicology
• /
• v.19 no.2
• /
• pp.161-167
• /
• 2004

Air quality monitoring is a primary activity for industrial and social environment. The government identifies the pollutants that each industry must monitor. Especially, the VOCs (Volatile Organic Compounds), which are very harmful to human body and environment atmosphere, should be controlled under the government policy. However, the VOCs, which have not been confirmed in emission sources are very difficult to monitor. It is needed to develop the monitoring system that allow the continuous and in situ measurement of VOCs mixture in different environmental matrices. Gas chromatography and mass spectrometry are the most prevalent current techniques among those available for the analysis of VOCs. But, they need a large size analytical instrument, which costs a great deal for purchase and operation. In addition, it has some limitations for realtime environmental monitoring such as location problems and slow processing time. Recently, several companies have commercialized a portable VOCs measurement systems, which cannot classify various kinds of VOCs but total quantities. We have developed a VOCs measurement system, which recognizes various kinds and quantities of VOCs, such as benzene, toluene, and xylene (BTX). Also, it can be used as a stand- alone type and/or fixed type in the vehicle with rack for real -time environmental monitoring.

• Journal of the Korean Society of Costume
• /
• v.60 no.5
• /
• pp.88-105
• /
• 2010

The purpose of this study is to grasp the actual wearing conditions, inconvenience and problems with cycle wear. To attain this purpose, a questionnaire was completed by direct observation and by interviewing bicyclists. The questionnaire was given to 273 bicyclists. The questionnaire consisted of items that are related to concerns with dressing appropriately and enhancement of physical performance through dress. Following are the results of this study. According to the survey, many of them purchased imported cycle wear rather than national cycle wear, and the satisfaction according with purchase rate was low. Bicyclists were uneasy with finding right size cycle wear especially for women. It turned out that the area of the knee and elbow are mostly the areas that they get hurt while riding. Even though the knee and elbow are the mostly hurt area, bicyclists do not prefer to wear appropriate protector for the knee and elbow to excel in their performance in cycling. In material related questions, lower dissatisfaction was indicated for the lints caused by fraction. Average satisfaction was indicated for the distortion after washing, changes in color, touch of the fabric, matters with static and sweat. With regard to the areas where the bicyclists felt discomfort was highly indicated with lower-body clothing. Discomfort was highly indicated with crotch area when riding long period of time. Also when riding a cycle, discomfort was indicated with the leggings cuffs when it comes upward with riding motion. Most of the bicyclists felt the tight fitting leggings were embarrassing.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2012.10a
• /
• pp.415-420
• /
• 2012

This paper proposes a novel type of tactile device utilizing magnetorheological (MR) fluid which can be applicable for haptic master of minimally invasive surgery (MIS) robotic system. The salient feature of the controllability of rheological properties by the intensity of the magnetic field (or current) makes this potential candidate of the tactile device. As a first step, an appropriate size of the tactile device is designed and manufactured via magnetic analysis. Secondly, in order to determine proper input magnetic field the repulsive forces of the real body parts such as hand and neck are measured. Subsequently, the repulsive forces of the tactile device are measured by dividing 5 areas. The final step of this work is to obtain desired force in real implementation. Thus, in order to demonstrate this goal a neuro-fuzzy logic is applied to get the desired repulsive force and the error between the desired and actual force is evaluated.

• Journal of the Korean Society of Costume
• /
• v.63 no.5
• /
• pp.102-114
• /
• 2013

This study performed the evaluation of skin temperature, heart rate, humidity and temperature inside clothing, and subjective sensation to estimate the physiological responses of the human body and its feeling of comfort for developing value-added dox fabric. Experiments were performed on five healthy adult women whose average age was 21, at climate chamber in which temperature, relative humidity and air current were set up below $28{\pm}5^{\circ}C$, $50{\pm}10%$, 0.2m/s, respectively. Two kinds of clothes were used for the experiments: 100% cotton and dox clothes. The clothes were identical in size and form, and the attire consisted of long-sleeved shirts, long trousers, and socks. The experiment was performed for 30 minutes using ergometer. The results are as follows. 1) It showed low skin temperature of forearm, breast, back, forehead and lower leg in exercise, but high skin temperature of them in recovery. However skin temperature of thigh and foot increased from rest to recovery. 2) It showed significant difference (p<0.001, p<0.01) in average skin temperature between cotton and dox clothes. Cotton clothes had a higher average skin temperature compared to dox. Not only was there a significant difference in temperature inside clothing (p<0.001), this was also the case with humidity inside the clothing (p<0.001).

• Transactions of the Korean Society of Automotive Engineers
• /
• v.23 no.1
• /
• pp.105-111
• /
• 2015

Since 2007, Insurance Institute of Highway Safety(IIHS) has conducted the new bumper test using bumper barrier to estimate the repair cost of impacted vehicle. In this study, for the front body FE model of a medium size passenger car analyzes were carried out to optimize the shape of backbeam center reinforcement bracket. First, overlap effect was examined with changing the overlap magnitude and spot welds were added along the backbeam center line for reducing the section shear deformation. Next, for an overlap model design parameter study was performed for the bracket. Thickness effect was examined and an inner reinforcement was added to the bracket. Also, the lower part of bracket was deleted and additionally the bracket length was extended. The results were discussed in terms of backbeam backward deflection, barrier backstop intrusion and weight. Compared with the current design, the final model showed 44.1% bracket weight reduction with 30.0% decrease of backbeam deflection.