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

  • Lee, Yong-Bum;Kook, Yoon-Bum;Choi, Sung-Mo
    • Journal of Korean Medical classics
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    • v.19 no.1 s.32
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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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    • v.2B no.3
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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.

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

  • Choi, Seul-Bi;Ryu, Jae-Kyun
    • Korean Journal of Applied Biomechanics
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    • v.22 no.1
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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).

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

  • Kang, Sun-Tae;Kim, Jeong-Mog
    • Journal of Korean Society of Water and Wastewater
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    • v.10 no.4
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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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Research about Thermal Stratification Effect on HCCI Combustion Fueled with Primary Reference Fuel (예혼합기의 열적성층화가 PRF연료의 예혼합압축자기착화에 미치는 영향)

  • Lim, Ock-Taeck
    • Transactions of the Korean Society of Automotive Engineers
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    • v.16 no.5
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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.

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

  • Shin, Choon-Sik;Kim, Heuy-Dong
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.11a
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    • pp.363-366
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    • 2010
  • Among the many different types of wind tunnels, Ludwieg Tube(LT) is the most suitable facility for high Reynolds number testing. Depending on the location of diaphragm, there are two types of LTs. In the present study, a computational work has been carried out to compare the operation characteristics of upstream- and downstream-diaphragm LTs. Two-dimensional, axisymmetric, unsteady, compressible Navier-Stokes equations were solved using a fully implicit finite volume scheme. Based on the present results, the flow mechanism of the starting process was discussed in detail using wave diagrams and characteristics of starting time and working time were investigated.

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

  • Oh, Jae-Eung;Yim, Tong-Kyu;Park, Kil-Su
    • The Journal of the Acoustical Society of Korea
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    • v.9 no.3
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    • pp.5-10
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    • 1990
  • This study was examined for traffic noise by platoon dispersion in relation to traffic flow till platoon reach steady driving condition after starting from stopline. Platoon dispersion factor was calculated and evaluated by the following input data : traffic volume, travel time, pass time.

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

  • Choi, I.K.;Woo, J.H.
    • Proceedings of the KIEE Conference
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    • 1999.07b
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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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A mathematical approach to motion planning for time-varying obstacle avoidance (시변 장애물 회피 동작 계획을 위한 수학적 접근 방법)

  • 고낙용;이범희;고명삼
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10a
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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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