• Korean Journal of Applied Biomechanics
• /
• v.12 no.2
• /
• pp.381-392
• /
• 2002

This study attempted to indentify changeability of the factorial structure of kinematic analysis in bowling. Subjects of group composed of three groups : Higher bowers who are national representative bowers with 200 average point and one pro-bowler. Middle bowlers who are three common persons with 170 average points. Lower bowler who are three common persons with 150 average points. Motion analysis on throw motion in three groups respectively has been made through three-dimension cinematography using DLT method. Two high-speed video camera at operating 180 and 60 frame per secondary. T-test factorial structure analysis has been used to define variable relations. It was concluded that : 1. The difference of x1, x2, x4, x8, x9, x11, x12, x13 where significant between two group. 2. The difference of number of spin and angle of the back-hand where statistically significant between two group(p<.001, p<.05) 3. The correlation over r=.5 between the kinematic data x1, x2, x3, x9, x10, x11. In the rotation loading matrix Factor 1 was x1, x2, x9, x10 and Factor 2 relates to x3, x11. 4. In order to obtain the factor score as follow as ; Factor 1 = (0.248)X1 + (0.265)X2 + (-0.074)X3 + (0.259)X9 + (0.259)X10 + (-0.025)X11 Factor 2=(-0.016)X1 + (-0.055)X2 + (0.84)X3 + (-0.013)X9 + (-0.007)X10 + (0.553)X11.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2002.02a
• /
• pp.289-296
• /
• 2002

배아부착률이 높은 배아미를 생산하기 위한 기초 연구로서, 현미의 함수율과 입형정미기 축회전속도가 쌀 배아부착률, 싸래기율, 백도, 동할율 등에 미치는 영향을 구명하고자 하였다. 본 연구에서 분석된 결과를 요약하면 다음과 같다. 1. 축회전속도에 관계없이 현미의 함수율이 배아부착률에 큰 영향을 줌을 알 수 있었다. 쌀의 배아부착률은 함수율 13.2%에서는 약 70%∼76%이었고, 함수율 13.4∼14.5%에서 약 66∼67%, 함수율 15.2%에서 약 38∼46%, 함수율 15.4%에서는 약 9∼10%로서, 함수율이 증가함에 따라 배아부착률은 함수율 15.4%에서 급격히 감소하였다. 또한, 축회전속도 900rpm일 때의 배아부착률이 1100rpm일 때의 배아부착률보다 함수율 13.2%∼15.2% 범위에서 약 2∼8% 높은 것을 알 수 있었다. 식미를 고려하고 높은 배아부착률을 갖기 위해서는 약 함수율 15.2% 이하에서 도정하는 것이 좋은 것으로 사료되었으며, 정미기 축회전속도의 감소로 함수율 15.2% 이하에서는 쌀의 배아부착률을 약 8%까지 높일 수 있었다. 2. 축회전속도에 관계없이 현미의 함수율 증가에 쌀의 백도는 약 23에서 40가지 점차 증가하는 경향을 보였으며, 특히 함수율 약 15.2% 이상에서는 약 40까지 급격히 증가하였다. 함수율 13.2%∼15.4%에서 축회전속도 1100rpm에서의 백도가 900rpm일 때 보다 약 1.3∼4.0정도 약간 놀게 나타났으나, 함수율 약 16.7% 이상에서는 그 차이는 거의 없었다. 즉 쌀의 백도는 함수율에 따라 결정적인 영향을 받음을 알 수 있었다. 3. 함수율이 정백공정중 싸래기율에 커다란 영향을 미침을 알 수 있었다. 현미의 함수율 13.4%에서 16.7% 범위에서는 두 축회전속도에서 같은 경향으로 싸래기율이 약 3.5%에서 약 1%까지 점차로 감소하였다. 그러나 함수율이 16.7% 이상일 때부터 싸래기율이 증가하였다. 또한, 함수율 약 15.2%가지는 축회전속도 1100rpm에서의 싸래기율이 900rpm일 때 보다 약 0.6%∼1.0% 높게 나타났다. 4. 함수율 13.2%부터 16.2%까지는 함수율에 따라 배아미의 동할율은 거의 약 9% 이하로 일정하였다. 또한, 함수율 13.2%∼14.5% 사이와 17%이상에서는 1100rpm에서의 동할율이 900rpm일 때 보다 더 높게 나타났다. 그리고 축회전속도에 관계없이 함수율 16.7%에서는 동할율이 약 10%, 함수율 약 17%에서는 동할율이 약 20%까지 급격히 증가하였다. 결론적으로, 함수율이 쌀의 배아부착률, 백도, 싸래기율, 동할율에 결정적인 영향을 주고 있으며, 다음으로 입형정미기 축회전속도 역시 배아부착률, 백도, 싸래기율, 동할율 등의 물성에 영향을 미침을 알 수 있었다.

• Korean Journal of Crystallography
• /
• v.3 no.1
• /
• pp.37-43
• /
• 1992

KTiOP04 is a nonlinear optical crystal which is most widely used for frequency doubling of the radiation of Nd : YAG laser. In the experiment, sin ale crystals of KTiOP04 were grown by TSSG technique using 3K2W04·P2O5 flux. Low temperature gradient furnace suitable for KTP single crystal growth was used. Seed crystal was placed at the surface of the solution for the purpose of better observation of the growing crystals and the possibility of diameter control. Solution included 66.7mol% KTiOP04 for all experiments and its saturation temperature was 1020℃. The conditions of single crystal growth were as follows: cooling rate 0.2℃/h, crystal rotation rate 50rpm, c -axis seed. Using these conditions, single crystals up to 23 ×25×25mm3 have been groan from about 100cc solution. We have also observed a change in the crystal growth habit which resulted in the formation of large (201) faces and small (100) faces. And some crystals have (101) faces.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.46 no.2
• /
• pp.95-105
• /
• 2018

Increasing cruise speed is an important issue for the development of the next generation rotorcraft. Among several concepts proposed by previous research, the rotorcraft with ducted fan demonstrates its possibility of high-speed flight. In this study, numerical simulations are conducted to investigate the aerodynamic and flow characteristics of multi-ducted fan in forward flight. The aerodynamic efficiency around front ducted fan is determined by interaction between free-stream velocity and the induced velocity. While flow characteristics of rear ducted fan are dominantly influenced by the front ducted fan. Separation in the front ducted fan occurs faster than that of rear ducted fan, and the separation at duct inlet induces an increase of fan thrust. As a result of interaction effect between each ducted fan, relatively aligned inflow enters to the rear ducted fan. Therefore, thrust of the rear fan is decreased steadily before separation, and sudden changes of thrust in fans occur simultaneously. Due to the pressure decrease on lower surface, the normal force of rotorcraft is reduced with forward speed.

• Journal of agriculture & life science
• /
• v.50 no.2
• /
• pp.187-194
• /
• 2016

The purpose of this study was to analyze temperature distribution characteristics using a model swine housing for temperature sensor adjustable positioning and developed a sensor and controller embedded exhaust fans utilizing ICT fusion technology for windowless swine housing. Temperature measured by the sensor attached on the exhaust fan was also determined that there is no problem, the temperature is located in the upper fan given the measured errors shown in the 1℃ temperature difference between the lower temperature than the other positions in the model swine housing. The performance of the exhaust fan at maximum output was found to be 1920rpm, air flow rate 125㎥/min. When the open area ratio of 70% one proper air volume of the exhaust fan was found to be 75㎥/min, 60pa. Maximum efficiency in all of the output of the exhaust fan is exhibited at about 70% open area ratio of the damper. The number of revolution of the exhaust fan was 1920rpm when the output was a maximum of 100%. AC output phase of the pulse duty ratio change of the controller was shown to change without delay. It was determined that the instant fan speed control is possible.

• Korean Journal of Food Science and Technology
• /
• v.12 no.1
• /
• pp.18-23
• /
• 1980

Rheological behaviors of red pepper paste acre investigated with rotational viscometer at $25{\sim}55^{\circ}C$ and the following results were obtained. 1. At shear rate of $0.323{\sim}1.653\;sec^{-1}$, red pepper paste was found to be a thixotropic food product which showed pseudoplastic proper ties and also exhibited a yield stress and time dependent characteristics. 2. At a shear rate of 0.978 $sec^{-1}$, flow behavior index, consistency index and yield stress were 0.597, 192.3 dyne $sec^s/cm^{2}$, and 91 dyne/$cm^{2}$ respectively. 3. Variation of consistency of red pepper paste with time was found to be decayed by a second order kinetic equation and thereafter nearly time independent. 4. Variation of consistency of red pepper paste with temperature was found to follow Andrade's equation and the activation energy as calculated on the basis of this equation was $1.03\;kcal/g{\cdot}mole$.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2003.05a
• /
• pp.173-176
• /
• 2003

지문은 종생불변성, 만인부동성, 그리고 사용상의 편리함 때문에 신원인증을 위한 생체인식에 많이 사용되고 있다. 최근에는 기하학구조에 기반한 특이점 매칭방식이 제안되어 인식성능이 매우 높고 잡음에 강한 특성이 있으나 매칭 회수가 많아 인식속도가 느린 단점이 있다. 따라서 기존의 방식은 소수의 지문에 대한 1:다 매칭이나 1:1매칭에 주로 사용된다. 본 논문에서는 기존의 문제점들을 개선하기 위하여 생체 면역계의 자기-비자기 인식 능력에 주목하였다. 생체 면역계는 자기-비자기의 구별 능력을 바탕으로 바이러스나병원균 등의 낮선 외부침입자로부터 자신을 보호하고 침입자를 식별, 제거하는 시스템이다. 본 논문에서는 생체 면역계를 이루는 면역세포 중의 하나인 세포독성 T세포의 생성과정에서 자기, 비자기를 구별하기 위한 MHC 인식부를 형성하는 과정에 착안한 빠르고 신뢰성 있는 지문 인식 알고리즘을 제안한다. 제안한 방식은 지문에 존재하는 특이점(minutiae)인식을 통해 1단계로 global 패턴을 생성하고 2단계로 기하학적인 구조를 만들며, 인식시 global 패턴을 인식한 MHC 인식부에 대해서만 2차 local 매칭을 수행함으로써 매칭 속도가 매우 빠르며 지문의 비틀림이나 회전 등에 대하여 강인하게 인식된다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.6 no.5
• /
• pp.432-438
• /
• 2005

In this paper, the high precision position control of AC Servo motor for semiconductor equipment is studied. The control system was implemented using TI DSP TMS320F2812 which has 150 MIPS speed for next generation motor control. The controlled 100W PMSM motor has 2,500 ppr optical incremental encoder. The control system has speed controller and current controller to control the motor position. The encoder pulses are divided into 4 times, which has 10,000 ppr and the motor system has the position accuracy of 1/10,000. If the resolution of the encoder is increased, the resolution of the position control will be increased.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
• /
• v.7 no.3
• /
• pp.301-310
• /
• 2017

Quantum-dot cellular automata(QCA) is an alternative technology for implementing various computation, high performance, and low power consumption digital circuits at nano scale. In this paper, we propose a new universal gate in QCA. By using the universal gate, we propose a novel XOR gate which is reduced time/hardware complexity. The universal gate can be used to construct all other basic logic gates. Meanwhile, the proposed universal gate is designed by basic cells and a rotated cell. The rotated cell of the proposed universal gate is located at the central of 3-input majority gate structure. In this paper, we propose an XOR gate using three universal gates, although more than five 3-input majority gates are used to design an XOR gate using the 3-input majority gate. The proposed XOR gate is superior to the conventional XOR gate in terms of the total area and the consumed clock because the number of gates are reduced.

• Proceedings of the KIEE Conference
• /
• 2007.10c
• /
• pp.110-111
• /
• 2007

두개의 유니모프 진동자를 이용한 새로운 형상의 마이크로 초음파 리니어 모터를 제안하였다. 유니모프 진동자는 금속판에 판상의 압전소자가 접착되어 있으며, 두개의 유니모프 진동자가 삼각형상의 진동 커플러에 의해 연결되어 스테이터를 구성한다. 스테이터는 두 가지 진동모드(대칭모드와 비 대칭모드)를 가지고 있으며, 이 두 진동모드가 축퇴되도록 설계하였다. 스테이터의 대칭모드와 비 대칭모드를 위상차 $90^{\circ}$로 여진시킴으로써 이동체의 직선(또는 회전) 운동을 발생시킬 수 있다. 시작기 모터는 놀이 0.9 mm, 폭 1 mm, 길이 7.5 mm이며, 구동전압 $100V_{op}$, 구동주파수 300 kHz로 구동되어, 모터 최대속도 0.3 m/s, 최대 추력 6 mN을 달성하였다.