• Journal of Biosystems Engineering
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• 제32권4호
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• pp.223-229
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• 2007

This study was conducted to develop a 2 row type band furrow tiller for a walking cultivator. The tillage and weeding operations in the furrow of dry fields has been done manually or chemical herbicide has been applied. The application of herbicide induces soil pollution and manual operation requires heavy labor. This 2-row type implement was developed to substitute this manual operation and to minimize soil pollution. The developed implement was composed of power transmitting device, tilling device, frame and tail wheel. The max. plowing width and depth were 300mm and 180mm, respectively. The revolutions of the hexagonal shaft and the tillage shaft were $227{\sim}376rpm$ and $355{\sim}590rpm$, respectively. The adequate working speed was $0.50{\sim}0.83m/s$ and the field capacity was $0.17{\sim}0.28hr/10a$.

• 대한의생명과학회지
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• 제15권3호
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• pp.241-247
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• 2009

Wound healing is a complex and highly organized biological response to injury that results in the loss of tissue integrity. Our particular interest was propolis, traditional used as an antimicrobial and an anti-inflammatory agent. The purpose of this study was to see the effects of propolis on healing of the laser induced wounds and the level of collagen formation. 808 nm laser (20 J) was irradiated on the back of rats. Irradiated wounds were divided into gel control and 6 experimental groups (3 and 5% of different three kinds of propolis). Gel type of propolis (supplied by Seoul Propolis Co., Daejeon, Korea) in water based were applied on the laser wound once daily for 14 days. One fourth of rats were sacrificed on $3^{rd}$, $7^{th}$, $10^{th}$, and $14^{th}$ day and each wound was evaluated for degree of wound healing and the level of collagen formation. Healing of wound was evaluated by measuring and comparing the width and depth of the wounds. The levels of collagen were increased in 3 and 5% gel groups comparing to control on $3^{rd}$ day and the collagen level were increased more on $7^{th}$ day. Wounds of the experimental groups showed better healing in width comparing to the healing of the control. The results of this study demonstrated that propolis accelerated healing of wounds induced by laser irradiation and good collagen formation.

• JSTS:Journal of Semiconductor Technology and Science
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• 제17권2호
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• pp.192-198
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• 2017

In this paper, we propose a novel double gate vertical channel tunneling field effect transistor (DVTFET) with a dielectric sidewall and optimization characteristics. The dielectric sidewall is applied to the gate region to reduced ambipolar voltage ($V_{amb}$) and double gate structure is applied to improve on-current ($I_{ON}$) and subthreshold swing (SS). We discussed the fin width ($W_S$), body doping concentration, sidewall width ($W_{side}$), drain and gate underlap distance ($X_d$), source doping distance ($X_S$) and pocket doping length ($X_P$) of DVTFET. Each of device performance is investigated with various device parameter variations. To maximize device performance, we apply the optimum values obtained in the above discussion of a optimization simulation. The optimum results are steep SS of 32.6 mV/dec, high $I_{ON}$ of $1.2{\times}10^{-3}A/{\mu}m$ and low $V_{amb}$ of -2.0 V.

• 대한물리치료과학회지
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• 제15권3호
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• pp.55-63
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• 2008

Background : The Purposes of this study were to understand difference between free walking and obstacle over walking through the naked eye and motion analysis device, and to review merits of obstacle walking training as item of functional assessment in clinical situations. Methods : All participants were male and performed 3 types of walking methods: free walking, obstacle over walking with low block(height=10cm, width=8cm), and obstacle over walking with high block(height=20cm, width=8cm). All walking were performed 3 trials respectively. Results : In the naked eye, initial contact with toes occurred more than heel strike in obstacle over walking, and the flexion angle of hip and knee were increased in obstacle over walking. On interpretations though motion analysis device, cadence, gait speed and weight accept were significant statistically(p<.05). Cadence and gait speed were decreased, and weight accept duration was increased in obstacle over walking. Rotation among three pelvic motions was significant statistically(p<.05), flexion among three hip motions was significant statistically(p<.05) and flexion among three ankle motions was significant statistically(p<.05). Rotation and flexion among three ankle motions was significant statistically(p<.05). Conclusion : Both the naked eye and interpretations of the device presented many difference between free walking and obstacle over walking. In overcrossing obstacles, many participants appeared walking strategy by perform initial contact with toes. Knee flexion was most significant statistically(p<.05) in obstacle over walking with 20cm block.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2001년도 추계 기술심포지움
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• pp.129-133
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• 2001

In this paper, hermetic sealing was studied fur wafer level packaging of the MEMS devices. With the flip-chip bonding method, this B-stage epoxy sealing will be profit to MEMS device sealing and further more RF-MEMS device sealing. B-stage epoxy can be cured 2-step and hermetic sealing can be obtained. After defining $500{\mu}{\textrm}{m}$-width seal-lines on the glass cap substrate by screen printing, it was pre-baked at $90^{\circ}C$ for about 30 minutes. It was then aligned and bonded with device substrate followed by post-baked at $175^{\circ}C$ for about 30 minutes. By using this 2-step baking characteristic, the width and the height of the seal-line were maintained during the sealing process. The height of the seal-line was controlled within $\pm0.6${\mu}{\textrm}{m}$ and the strength was measured to about 20MPa by pull test. The leak rate of the epoxy was about $10^7$ cc/sec from the leak test.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2000년도 학술대회논문집
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• pp.30-34
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• 2000

This study minimized the address pulse width for plasma display by analysis of address discharge condition for high speed driving using the ADS driving scheme. As a result, addressing pulse width of 1$mutextrm{s}$ has been realized and luminance of 560cd/$m^2$ can be obtained from the area of 256X160 pixels. And a new AWD scheme is proposed. We accomplished 9.1-inch-diagonal color image with the scan timing of HDTV class PDP, display duty 96.8%.

• 전자공학회논문지A
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• 제33A권4호
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• pp.121-128
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• 1996

The impact ionization rate of thethighly-doped AlGaAs/GaAs quantum well structure is calculated, which is an important parameter ot design theinfrared detector APD and the novel neural device. In conjunction with ensemble monte carlo method and quantum mechanical treatment, we analyze the effects of the parameters of quantum well structure on the impact ionization rate. Since the number of the occupied subbands increases while the energy of the subbands decreases as the width of quantum well increases, the impact ionization rate increases in the range of th esmall well width but gradually the increament slows down and is finally saturated. Due to the effect of the energy of the injected electrons into the quantum well and the tunneling through the barrier, the impact ionization rate increases for the range of the small barrier width and decreases for the range of the large barrier width. Thus, there exists a barrier width to maximize the impact ionzation rate for a mole fraction x, and the barrier width moves to the larger vaue as the mole fraction x increases. The impact ionization rate is much more sensitive to the variation of the doping density than that of the other quantum well parameters. We found that there is a limit of the doping density to confine the electronics in the quantum well effectively.

• 전자공학회논문지A
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• 제32A권9호
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• pp.128-134
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• 1995

A fiber-optic temperature sensor utilizing an optical absorption device (InP) was fabricated. The spectrum of transmitted light through an InP device was obtained at the three temperatures(249 K, 369 K). A stabilized LED(light emmiting diode) driver, photoreceiver, and signal proocessing electronics were designed. An intensity referencing technique was adopted in order to minimize the fluctuation of output signal due to external pertubation of the transmitting optical fiber. The optical absorption edge of the InP device moves to longer wavelength at a rate of 0.42 nm / K, and energy gap of InP is 1.35 eV at room temperature. From these results, it is concluded that the InP device has temperature dynamic range of 300 K with LED of center wavelength of 940nm and spectral width of 50nm. The designed fiber-optic temperature sensor system showed good linearity within the temperature range from -30$^{\circ}C$ to + 150$^{\circ}C$.

• 한국의류산업학회지
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• 제13권6호
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• pp.926-933
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• 2011

The purpose of this research was to develop a smart wear equipped with wearable technologies for women in the age of 50's and 60's and confirm its acceptability. For this, we constructed a casual jacket that has the integration of heating and lighting function, and evaluated the user's satisfaction. The size of the heating device attached at the back of the jacket was 300 mm in width and 120 mm in length and the size of the one attached at the front abdomen was 180 mm in width and 120 mm in length. The power supplier was the unification of the battery and controller which have been waterproofed. The lighting device connected with LED was 26mm in width, 20 mm in length and 1.5 mm in thickness. It has been designed in a waterproofed rectangular shape and was attachable to the jacket. The satisfaction survey of a smart jacket has been conducted with three standards, which were convenience, appearance and practicality. Free physical movement among the standard of convenience had very high scores with the average of 4.7 on a five point-scale. The acceptability of the jacket was 4.6, which proved that it didn't have unique feelings compared to ordinary ones. The evaluation score of the appearance of the jacket was 4.5. Especially inside finishing of the jacket received the highest scores from all ages. According to the evaluation of practicality, there has been no change in the appearance of the jacket and the function of heating device after laundry.

• 대한조선학회 특별논문집
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• 대한조선학회 2013년도 특별논문집
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• pp.73-80
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• 2013

From broad point of view, seam tracking has been one of main issues with respect to welding automation. Several attempts have been successful for seam tracking of fixed weaving width. As a solution of the seam tracking methods for varying groove width, the visual sensors such as CCD cameras have been adopted. Although the vision sensing techniques can achieve high accuracy, the weak point is that well-prepared vision sensor environment should be required to obtain high-quality visual measurements which can be easily affected by significant noises in industrial areas. This paper proposed an alternative seam tracking algorithm for narrow groove. A special measurement device for arc voltage, in this study, is developed to enhance the reliability of the measured welding signals. Based on the developed arc sensor algorithm, an automatic weld-width tracking algorithm is also proposed, which is able to predict the weld-position more accurately. The usefulness of the automatic weld-width tracking algorithm was well verified by applying it to gas tungsten arc welding (GTAW).