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Gas-Chromatography를 이용한 은교산 전탕시간에 대한 연구 (Study on the most effective Yinqiao San by the GC(Gas Chromatography))

  • 이용범;국윤범;최성모
    • 대한한의학원전학회지
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    • 제19권1호통권32호
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    • pp.202-206
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    • 2006
  • Yinqiao San is the medicine for the outer part disease of the human body. In ${\ulcorner}$Wenbingtiobian${\lrcorner}$, this medicine is the most useful when it is used within short time after the starting boiling it. In this study, the volatile ingredients of the Yinqiao San were observed by GC and compared with each other in time scale. Most of the ingredients were observed about 5 min after the starting boiling it, after10 min., the GC peaks were smaller and smaller, and after 2 hours and 30 min. the GC peaks were almost gone. It is confirmed that was written about the Yinqiao San in ${\ulcorner}$Wenbingtiobian${\lrcorner}$.

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A Novel Position Sensorless Speed Control Scheme for Permanent Magnet Synchronous Motor Drives

  • Won, Tae-Hyun;Lee, Man-Hyung
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • 제2B권3호
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    • pp.125-132
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    • 2002
  • PMSMS (permanent magnet synchronous motors) are widely used in industrial applications and home appliances because of their high torque to inertia ratio, superior power density, and high efficiency. For high performance control, accurate informations about the rotor position is essential. Sensorless algorithms have lately been studied extensively due to the high cost of position sensors and their low reliability in harsh environments. A novel position sensorless speed control for PMSMs uses indirect flux estimation and is presented in this paper. Rotor position and angular velocity are estimated by the proposed indirect flux estimation. Linkage flux and magnetic field flux are calculated by the voltage equations and the measured phase current without any integration. Instead of linkage flux calculation with integral operation, indirect flux and differential magnetic field are used for the estimation of rotor position. A proper rejection technique fur current noise effect in the calculation of differential linkage flux is introduced. The proposed indirect flux detecting method is free from the integral rounding error and linkage flux drift problem, because differential linkage flux can be calculated without any integral operation. Furthermore, electrical parameters of the PMSM can be measured by the proposed TCM (time compression method) for soft starting and precise estimation of rotor position. The position estimator uses accurate electrical parameters that are obtained from the proposed TCM at starting strategy. In the operating region, a proper compensation method fur temperature effect can compensate fir the estimation error from the variation of electrical parameters. The proposed novel position sensorless speed control scheme is verified by the experimental results.

국가대표 크로스컨트리 스키 선수들의 Start & Finish 구간에 대한 Double poling 기술의 운동학적 분석 (The Kinematic Analysis about Double Poling Technique of National Cross-Country Skiers at Start & Finish Phases)

  • 최슬비;류재균
    • 한국운동역학회지
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    • 제22권1호
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    • pp.95-104
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    • 2012
  • The purpose of this study targeted to national cross-country skiers representatives was to implement hypothetical experiment on their patterns of the movements and analysis on kinematic variables occurred while double polling was conducted between starting and finishing phase of 56 meters. Furthermore, it aimed to provide a set of quantitative data to illustrate how to improve one's skill and performance of sprint. In our experiments, we conducted 3-dimension analysis of cycle characteristics, joint angle(hip, knee and elbow), and pole angle. The results showed that at the starting phase, the players did not show a significant difference in attributes of time and distance. In heat 1 where elbow angle and polling starts, the pole angle was noticeably high in heat 1. At the finishing phase, there was a considerable distinction with a high frequency in performing a short polling time and high speed in heat 3. The players showed large extension between the flexion and of the hip angle which indicates high contribution given from the movement of lower body(hip, knee).

Phenol 함유폐수의 처리를 위한 영향인자와 성능특성 (Influence factors and Efficiencies Characteristics for Treatment of Wastewater Containing Phenol)

  • 강선태;김정목
    • 상하수도학회지
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    • 제10권4호
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    • pp.119-126
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    • 1996
  • Influence factors and efficiency characteristics for treatment of wastewater containing phenol were studied with using Pseudomonas sp. B3. It took 130 hours to remove phenol, when only activated sludge of terminal disposal palnt of sewage was innoculated in batch culture, but it was required just 36 hours, when bacteria degrading phenol and activated sludge were simultaneously innoculated. If only phenol an carbon source was used, it necessary 36 hours for biodegradation of phenol, while glucose was added to medium, it took 73 hours. It was revealed as excellent effluent and SVI, when the F/M ratio, COD and phenol concentration were 53mg/l and 1.2mg/l, respectively, and optimum F/M ratio was revealed 0.31. The reactor were seriously shocked as reducing hydraulic retention time at constant phenol concentration more than increasing phenol concentration at constant hydraulic retention time, when volumetric loading rate was increased to $0.8kg\;phenol/m^3{\codt}d$ from $1.6kg\;phenol/m^3{\codt}d$. And also the effluent phenol concentration was 34mg/l after starting 12 hours of shocking and reactor was recovered as steady state after 65 hours of changing in the former test. Although the effluent phenol concentration was maximum value with 12mg/l after starting 20 hours of shocking and reactor was recovered as steady state after 54 hours of changing in the later test.

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예혼합기의 열적성층화가 PRF연료의 예혼합압축자기착화에 미치는 영향 (Research about Thermal Stratification Effect on HCCI Combustion Fueled with Primary Reference Fuel)

  • 임옥택
    • 한국자동차공학회논문집
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    • 제16권5호
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    • pp.157-163
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    • 2008
  • The HCCI combustion mode poses its own set of narrow engine operating by knocking. In order to solve this, inhomogeneity method of mixture and temperature is suggested. The purpose of this research is to get fundamental knowledge about the effect of thermal stratification on HCCI combustion of PRF -Air mixture. The temperature stratification is made by buoyancy effect in combustion chamber of RCM. The analysis items are pressure, temperature of in-cylinder gas and combustion duration. In addition, the structure of flames using the two dimensional chemiluminescence's images by a framing camera are analyzed. Under stratification, the LTR starting time and the HTR starting time are advanced than that of homogeneous. Further, the LTR period of homogeneous conditions became shorter than that of the stratified conditions. With the case of homogeneous condition, the luminosity duration becomes shorter than the case of stratified condition. Additionally, under stratified condition, the brightest luminosity intensity is delayed longer than at homogeneous condition.

상류막 방식과 하류막 방식의 Ludwieg Tube에서 발생하는 유동특성에 관한 연구 (A Study on the Flow Characteristics in the Upstream- and Downstream-Diaphragm Ludwieg Tubes)

  • 신춘식;김희동
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2010년도 제35회 추계학술대회논문집
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    • pp.363-366
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    • 2010
  • 여러 형태의 풍동장치 중에서 Ludwieg Tube(LT)는 높은 레이놀즈수 유동을 실현할 수 있는 가장 적합한 장치로 알려져 있다. 일반적으로 LT는 격막의 위치에 따라 두 종류로 구분된다. 본 연구에서는 상류막 방식과 하류막 방식 LT의 작동특성을 조사하기 위하여, 수치해석적인 방법을 적용하였다. 수치해석에서는 2차원 축대칭, 비정상, 압축성 Navier-Stokes 방정식에 유한체적법을 적용하였다. 그 결과, 본 수치해석은 시동과정의 유동 메커니즘을 파동선도를 이용하여 상세하게 설명하였으며, 시동 시간과 작동시간의 특성을 조사하였다.

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차량군의 분산에 따른 교통소음 변화에 관한 연구 (A study on traffic Noise by Platoon Dispersion)

  • 오재응;임동규;박길수
    • 한국음향학회지
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    • 제9권3호
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    • pp.5-10
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    • 1990
  • 출발정지선에서 대열을 이룬 차량군이 녹생신호에 의해 출발하면서부터 발생되는 소음을 차량군의 동적특성과 관련지어 차량군의 분산과 소음과의 관련성을 밝히고저 하였다. 차량군의 분산은 분산펙터(P.D.F.) 개념을 이용하였으며 분산펙터는 교통량, 주행시간, 대얼통과시간으로부터 산출되었다.

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양수발전소 속도조정율 향상 및 수력적 부도시간에 관한 연구 (A study on the speed regulation improvement and water starting time of pumped storaged power plant)

  • 최인규;우주희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 B
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    • pp.743-745
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    • 1999
  • In these days, pumped storaged power plants are under operations mainly for load regulation in power system. After we investigated the governor related electrical circuit of a pumped storaged power plant, we measured speed regulation and dead time of both the governor and the hydraulic system according to the change of variables of the governor during generation. After that the measured speed regulation improved much.

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시변 장애물 회피 동작 계획을 위한 수학적 접근 방법 (A mathematical approach to motion planning for time-varying obstacle avoidance)

  • 고낙용;이범희;고명삼
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 26-27 Oct. 1990
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    • pp.388-393
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    • 1990
  • A robot manipulator and an obstacle are described mathematically in joint space, with the mathematical representation for the collision between the robot manipulator and the obstacle. Using these descriptions, the robot motion planning problem is formulated which can be used to avoide a time varying obstacle. To solve the problem, the constraints on motion planning are discretized in joint space. An analytical method is proposed for planning the motion in joint space from a given starting point to the goal point. It is found that solving the inverse kinematics problem is not necessary to get the control input to the joint motion controller for collision avoidance.

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