• Title/Summary/Keyword: PULSE

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A Study for Performance Improvements in the Coaxial Type Stirling Pulse Tube Cryocooler (동축형 스털링 맥동관 냉동기의 성능개선에 관한 연구)

  • Park, S.J.;Hong, Y.J.;Kim, H.B.;Kim, Y.H.
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.1329-1334
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    • 2004
  • The most compact and convenient pulse tube cryocooler for practical applications is the coaxial type. It can replace Stirling cryocooler without any change to the Dewar or the connection to the cooled devices. The experimental results of the coaxial inertance tube pulse tube cryocooler for cooling superconductor RF filter are presented in this paper. To find optimal conditions of inertance tube pulse tube cryocooler, no load temperature according to the variations of inertance tube volume, reservoir volume are measured, and the cool down characteristics at the particular conditions are presented. In case of the coaxial type inertance tube pulse tube refrigerator, cool down time is the lowest in the inertance tube diameter of 1.3 mm and inertance tube length of 1900 mm and lowest temperature is 112K. This results are not satisfactory for practical applications. So, We propose vacuum insulation between regenerator and pulse tube in the Stirling type coaxial pulse tube cryocooler. Stirling type coaxial pulse tube cryocooler with the vacuum insulation between regenerator and pulse tube was designed and manufactured by KIMM(Korea Institute of Machinery and Materials). The optimal conditions will be tested for Stirling type coaxial pulse tube cryocooler with the vacuum insulation between regenerator and pulse tube.

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A Case Study of Six Sigma Project for Improving method of measuring pulse wave (6시그마 기법을 통한 안정된 맥파측정 프로세스 설계)

  • Lee, Jeon;Lee, Yu-Jung;Lee, Hae-Jung;Choi, Eun-Ji;Kim, Jong-Yeol
    • Korean Journal of Oriental Medicine
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    • v.12 no.2 s.17
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    • pp.85-92
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    • 2006
  • Pulse is one of the basic diagnostic information of TKM(Traditional Korean Medicine). To quantify and standardize pulse diagnosis, we had collected an amount of clinical data from May 2005 by using newly developed pulse analyzer. But there were many noises in pulse wave according to measuring method, environment, operator and condition of patient. So some data can’t be included for analyzing diagnosis. To reduce noises from measuring pulse and to collect reliable pulse wave data, we made the process map of measuring method and applied six sigma project. With this we can improved the method of measuring pulse wave in collecting clinical data. The project follows a disciplined process of five macro phases: define, measure, analyze, improve and control (DMAIC). A process map and C-E diagram are used to identify process input and output variables. The major input variables are selected by using C&E matrix, and process map is developed by analyzing input variables. And the optimum process conditions are going to be controled to avoid in increasing loss of collecting pulse wave data.

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AIx Change According to Pressing Angle and Pressing Force of the Radial Artery Pulse by Tonometry (토노메트리 방식 맥파 측정의 가압 각도와 가압력에 따른 AIx 변화)

  • Cho, JungHee;Jeon, Young Ju;Jun, Min-Ho;Kim, Young-Min
    • Journal of Sensor Science and Technology
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    • v.27 no.4
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    • pp.259-263
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    • 2018
  • A radial artery pulse wave is measured while pressing an artery with constant force. However, pulse waveform measurements vary depending on pressing force and direction. Accurate pulse waveform measurements are important for analysis. Thus, it is necessary to define the measurement range of the permissible force and direction from which a correct pulse waveform is derived. In this study, pulse waves were generated by a pulse wave generator for accurate control. The pulse waves generated for different angles and pressing forces were analyzed. The augmentation index (AIx), which is the most commonly used index for evaluating vascular stiffness, was analyzed. The AIx was measured within ${\pm}6^{\circ}$ of the vessel direction and within ${\pm}8^{\circ}$ perpendicular to the vessel direction with a force that was 25% or more of the pressing force at which the maximum pressure wave was generated. We identified the applicable pressing force and angle range by analyzing the effect of pressing angle on the pulse wave. The AIx analysis performed using the pulse wave measurement device is reliable and reproducible.

Modern Medical Scientific Study on the String Pulse (현맥의 특징에 대한 현대 의학적 고찰)

  • Ryu, Hyun-Hee;Lee, Jeon;Jeon, Young-Ju;Lee, Yu-Jung;Lee, Si-Woo;Kim, Jong-Yeol
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.3
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    • pp.535-539
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    • 2008
  • Pulse diagnosis is one of the typical examination methods in traditional oriental medicine. Pulse type classification is a major element of this diagnosis. There are more than 20 pulse types which have each clinical significance. However, pulse type's indications are implicative and obscure. In this study, we reviewed string pulse which is often diagnosed in Traditional Korean Medicine by analysis of Traditional Oriental Medical Literatures and modern medical papers. String pulse is taut and stiff pulse with high tension and low softness. It appears in 'blood vessel endothelial dysfunction', 'autonomic imbalance', 'arteriosclerosis'. Persistent string pulse can bring about cardiovascular or central nervous disease.

A Pilot Study on Pulse Energy Measured by 3D Blood Pressure Pulse Analyzer in Women with Mild Hyperemesis Gravidarum (임신오조 환자의 맥파 분석 예비 연구)

  • Bae, Ju-Eun;Yoon, Young-Jin
    • The Journal of Korean Obstetrics and Gynecology
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    • v.28 no.4
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    • pp.21-30
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    • 2015
  • Objectives : The purpose of this study was to analyze the characteristics of the pulse energy in women who complained mild hyperemesis gravidarum. Methods : We analyzed the values of pulse energy on 14 patients who suffered mild hyperemesis gravidarum. The patients’ symptoms were assessed by PUQE (Pregnancy-Unique Quantification of Emesis scale). Statistical analysis was performed using SPSS 18.0 for window program, one way ANOVA, pearson correlation coefficient. Results : The results were as follows. 1. There were no statistically significant pulse energy differences. 2. The Chon pulse energy showed negative correlations with each Kwan and Cheok. 3. PUQE score showed positive correlations with right Chon pulse energy and negative correlations with right Kwan pulse energy. Conclusions : The result suggested that PUQE score changes be positive related with spleen pulse energy and negative related with lung pulse energy.

A EMTP Simulation of High-Voltage Pulse Transformer for Pulsed Power System (펄스파워 시스템용 고전압 펄스변압기의 EMTP 시뮬레이션)

  • Kim, Min-Soo;Lee, Hyong-Gu;Ju, Heung-Jin;Ko, Kwang-Cheol;Kan, Hyong-Bu
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.1984-1986
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    • 2000
  • In pulsed-power techniques. Marx generator is generally used for the high-power device. but this generator has insulation and spatial problems. So we will suggest a pulse transformer that has a small size to generate the high voltage pulse instead of Marx generator. In this paper, Pulse duration is 4 [${\mu}s$] and the ratio of input and output voltage is 40[kV]/200[kV](step-up ratio=5). The output voltage and the process of pulse compression for pulse circuit are simulated by EMTP (Electro-Magnetic Transient Program). The secondary voltage of pulse transformer is about 200[kV] and pulse width is 4[t/s]. When the secondary winding of the pulse transformer is saturated. the pulse width is 1.25[${\mu}s$]. We selected dummy load 50[$\Omega$] for impedance matching. The pulse voltage of dummy load is 100[kV] and pulse width is 500[ns].

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Generation of Ultrawide Band Electromagnetic Pulse from Blumlein Pulse Forming Line

  • Jin, Yun Sik;Kim, Jong Soo;Cho, Chuhyun;Roh, Young Su
    • Journal of Electrical Engineering and Technology
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    • v.9 no.2
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    • pp.677-681
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    • 2014
  • A high voltage pulse generator was fabricated to radiate ultrawide band electromagnetic pulse. A coaxial type of Blumlein pulse forming line is employed to produce a pulse of high voltage (>300 kV) and short pulse duration (~5 ns). A helical strip/wire type of air-cored pulse transformer was used to charge the Blumlein pulse forming line up to more than 300 kV. A peaking switch is essential to make the pulse rise time as fast as possible. Typically, the rise time is ~500 ps. The output pulse of the generator is radiated into air through an exponentially tapered TEM horn antenna. The electric field intensity of a radiated pulse was measured as a function of the distance from the transmitting horn as well as the output voltage of the peaking switch. The peak-to-peak value of the electric field intensity at 10 m from the TEM antenna was~100 kV/m.

Suggestion for Objective Evaluation of Comparative Pulse Diagnosis

  • Jun-Sang Yu
    • Journal of Pharmacopuncture
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    • v.27 no.1
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    • pp.21-26
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    • 2024
  • Objectives: Pulse is a method of Korean medicine diagnosis and is an important clue to detect the organs, nature, and progress of the disease. Pulse examination is included in the basic examination of Korean medicine doctors, but there is no standardized method for diagnosing pulse although the types and methods of the pulse taking are briefly described in the literature, making it difficult to spread the examination method. In this regard, I would like to propose an objective evaluation method. Methods: Although the importance of pulse examination and the method of pulse examination are known in the literature, it is difficult for undergraduate students or inexperienced Korean medicine doctors to access it, so in this paper a method of marking the size of the pulse power in the blank space for objective evaluation was devised and presented. Results: The size of the pulse power should be indicated using the 1-cell, 3-cell, or 5-cell method according to the left and right wrists and the cun, guan and chi on both sides. Conclusion: The method of pulse diagnosis is an important diagnostic method as a verification process for making a Korean medical diagnosis. The remaining Korean medicine diagnostic methods, including pulse diagnosis, also need to undergo objectification. It is believed that the objectification of these diagnostic methods will lead to an improvement in the treatment rate of Korean medicine.

Signal Change and Compensation of Pulse Pressure Sensor Array Due to Wrist Surface Temperature (손목 피부 온도에 의한 맥센서 어레이(array)의 신호 변동 및 보정)

  • Jun, Min-Ho;Jeon, Young Ju;Kim, Young-Min
    • Journal of Sensor Science and Technology
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    • v.26 no.2
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    • pp.141-147
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    • 2017
  • A pressure sensor in pulse measurement system is a core component for precisely measuring the pulse waveform of radial artery. A pulse sensor signal that measures the pulse wave in contact with the skin is affected by the temperature difference between the ambient temperature and skin surface. In this study, we found experimentally that the signal changes of the pressure sensors and a temperature sensor were caused by the temperature of the wrist surface while the pressure sensor was contacted on the skin surface for measuring pulse wave. To observe the signal change of the pulse sensor caused by temperature increase on sensor surface, Peltier device that can be kept at a set temperature was used. As the temperature of Peltier device was kept at $35^{\circ}C$ (the maximum wrist temperature), the device was put on the pulse sensor surface. The temperature and pressure signals were obtained simultaneously from a temperature sensor and six pressure sensors embedded in the pulse sensor. As a result of signal analysis, the sensor pressure was decreased during temperature increase of pulse sensor surface. In addition, the signal difference ratio of pressure and temperature sensors with respect to thickness of cover layer in pulse sensor was increased exponentially. Therefore, the signal of pressure sensor was modified by the compensation equation derived by the temperature sensor signal. We suggested that the thickness of cover layer in pulse sensor should be designed considering the skin surface temperature.

Development of the pulse analyzing system using FBG (FBG를 이용한 맥진 시스템 개발)

  • Jeon, Young-Ju;Lee, Jeon;Ryu, Hyun-Hee;Lee, Jae-Hoon;Lee, Si-Woo;Kim, Jong-Yeol
    • Korean Journal of Oriental Medicine
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    • v.13 no.3
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    • pp.105-110
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    • 2007
  • This work reports the pulse diagnosis system using FBG sensors which can display pulse signals detected while oriental medical doctors are conducting pulse diagnoses and simultaneously pressing the sensors by three fingers. Each optical fiber has five FBG sensing units fabricated in 2 mm width and 2 mm inter-sensor spacing. Three optical fibers with the FBG units in the parallel line configuration are then placed on each finger-pressing region and thus overall 9 fibers are used for the pulse measurements on the so-called "chon", "gwan", and "ch대k". A fixture holding the optical fiber arrays is able to adjust the height of the FBG sensing units while placing the fibers on the wrist. The pulse signals detected by the FBG sensors from chon, kwan, and chuk have been analyzed using 4 channel spectrum analyzer connected to the optical fibers. The measured pulse signals exhibit variations due to the nonuniform pressure distributions applied. resulting in the differences in the detected pulse signals between fiber lines. However. this work is the first step towards objective and quantitative analyses of the pulse diagnosis in oriental medicine which has traditionally been performed on subjective basis. Future works will be devoted to improving sensor stability, developing the way applying pressure and algorithms reporting the objective classification of the pulse status from systemic measurements using the sensors instead of relying on the clinicians' diagnoses subjectively performed. A successful pulse diagnosis system emerging in the future is expected to contribute to education as well as promoting pulse diagnosis in oriental medicine to the scientific research area.

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