• Title/Summary/Keyword: Pulse time

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Studies on the Mathematical Modelling of the Pulse-CVI for the Infiltration of Siliconcarbide from Methyltrichlorosilane (메틸삼염화규소로부터 탄화규소 침착의 Pulse-CVI에 대한 수치모사 연구)

  • Kim, In-Goo;Kim, Min-Ki;Chung, Gui-Yung
    • Composites Research
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    • v.18 no.5
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    • pp.27-33
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    • 2005
  • In this research, the mathematical modelling of the pulse-CVI (Chemical Vapor Infiltration) for the preparation of siliconcarbide/carbon composite. Each pulse consists with the gas injection time, the reaction time and the evacuation time. Effects of the reaction time and the evacuation time were studied. Additionally, the effects of the reactant concentration and the pressure were observed. The benefits of the pulse-CVI such as the uniform infiltration of siliconcarbide into the carbon preform and the short reaction time were certified.

A Study on the Dependency of Pulsed-DC Sputtered Aluminum-doped Zinc Oxide Thin Films on the Reverse Pulse Time (Pulsed-DC 스퍼터링에서 Reverse Pulse Time에 따른 AZO 박막의 특성 변화에 관한 연구)

  • Ryu, Hyungseok;Zhao, Zhenqian;Kwon, Sang Jik;Cho, Eou Sik
    • Journal of the Semiconductor & Display Technology
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    • v.17 no.4
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    • pp.32-36
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    • 2018
  • For various oxygen($O_2$) to argon(Ar) gas ratio, aluminum-doped zinc oxide(AZO) films were deposited for 3 min at different duty ratio by changing reverse pulse times. As the duty ratio increased, the thickness of the AZO film decreased and the sheet resistance increased. It can be concluded that When sputtering AZO Thin film, oxygen interfered with sputtering. When the reverse time was increased, the thickness of AZO was proportional to the real sputtering time and decreased. From the optical transmittance and sheet resistance, it was possible to obtain a higher figure of merits of AZO at a lower reverse pulse time. Even at the short reversed pulse time, it can be concluded that the accumulated charges on the AZO target are completely cleared. At a lower reverse pulse time, pulsed-DC sputtering of AZO is expected to be used instead of DC sputtering in the deposition of transparent conductive oxide(TCO) films without any degradation in thickness and structural/electrical characteristics.

Analysis of Linear Time-invariant System by Using a New Block Pulse Operational Matrices (새로운 일반형 블럭 펄스 적분 연산 행렬을 이용한 선형 시불변 시스템 해석)

  • Lee, Hae-Ki;Kim, Tai-Hoon
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.53 no.4
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    • pp.175-182
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    • 2004
  • This paper presents a new method for finding the Block Pulse series coefficients, deriving the Block Pulse integration operational matrices and generalizing the integration operational matrices which are necessary for the control fields using the Block Pulse functions. In order to apply the Block Pulse function technique to the problems of state estimation or parameter identification more efficiently, it is necessary to find the more exact value of the Block Pulse series coefficients and integral operational matrices. This paper presents the method for improving the accuracy of the Block Pulse series coefficients and derives generalized integration operational matrix and applied the matrix to the analysis of linear time-invariant system.

Parameter Estimation of The Distributed System via Improved Block Pulse Coefficients Estimation

  • Kim, Tai-hoon;Shim, Jae-sun
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.61.6-61
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    • 2002
  • In these days, Block Pulse functions are used in a variety of fields such as the analysis and controller design of the systems. In applying the Block Pulse function technique to control and systems science, the integral operation of the Block Pulse series plays important roles. This is because differential equations are always involved in the representations of continuous-time models of dynamic systems, and differential operations are always approximated by the corresponding Block Pulse series through integration operational matrices. In order to apply the Block Pulse function technique to the problems of continuous-time dynamic systems more efficiently, it is necessary to find th...

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Variable Pulse Generation Technology of Pusle ND:YAG Laser Using Real Time Multi-Discharge

  • Kim, Whi-Young
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.102.2-102
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    • 2001
  • In this study, a solid-state laser system adopting a new real time multi-discharge (RTMD) method in which three flashlamps are turned on consecutively was designed and fabricated to examine the pulse width and the pulse shape of the laser beams depending upon the changes in the lamp turn-on time. That is, this study shows a technology that makes it possible to make various pulse shapes by turning on three flashlamps consecutively on a real-time basis with the aid of a PIC one-chip microprocessor, With this technique, the lamp turn-on delay time can be varied more diversely from 0 to 10 ms and the real-time control is possible with an external keyboard, enabling various pulse shapes. In addition, longer pulses can be more widely used for industrial processing and lots of medical purposes.

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The Effects of Sa-Am Spleen-tonifying Acupuncture on Radial Pulse in Healthy Human Subjects (비정격(脾正格) 자침이 정상 성인 맥파(脈波) 변화에 미치는 영향)

  • Yoon, Kwang Sik;Lee, Hyun
    • Journal of Acupuncture Research
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    • v.30 no.4
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    • pp.1-14
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    • 2013
  • Objectives : The purpose of this study is to investigate the effects of Sa-Am spleen-tonifying acupuncture on radial pulse in healthy human subjects. Methods : Forty healthy human subjects participated in this study, divided into acupuncture group and control group. Radial pulse was measured by 3 dimensional pulse imaging system(DMP-3000) before, right after, 30 minutes after and 60 minutes after acupuncture in the acupuncture group. The subjects in the control group didn't received acupuncture but took a rest and then the radial pulse was measured at the same time points as the acupuncture group. The parameters were analyzed by gender, measuring location, and measuring time point. However the time related parameters exceptionally were analyzed without distinction of measuring location. Results : 1. T, variance of period, T2/T, T4/T, (T-T4)/T, T4/(T-T4), and W significantly changed after acupuncture. 2. Pressure, amplitude of H1, amplitude of H2, Amplitude of H4 and pulse energy significantly changed after acupuncture. 3. Pulse area, systolic pulse area and diastolic pulse area significantly changed after acupuncture. 4. Elasticity, AIx and AIx/HR significantly changed after acupuncture. Conclusions : The effect of Sa-Am spleen-tonifying acupuncture in healthy human may be observed on time, amplitude, pulse area and augmentation index. Further studies on the effects of Sa-Am acupuncture using radial pulse are needed.

Peripheral Blood Flow Velocity and Peripheral Pulse Wave Velocity Measured Using a Clip-type Pulsimeter Equipped with a Permanent Magnet and a Hall Device

  • Kim, Keun-Ho;Lee, Sang-Suk
    • Journal of Magnetics
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    • v.20 no.1
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    • pp.47-51
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    • 2015
  • We measured radial arterial pulse signals using a prototype of a clip-type pulsimeter equipped with a permanent magnet and a Hall device, which produced signals through a voltage-detecting circuit. The systolic peak time and the reflective peak time for a temporally pulsed signal were analyzed for an arbitrary pulse wave at one position of a small permanent magnet. The measured value of the peripheral pulse wave velocity was about 1.25-1.52 m/s, demonstrating the accuracy of this new method. To measure the peripheral blood flow velocity, we simultaneously connected the radial artery pulsimeter to a photoplethysmography meter. The average value of the peripheral blood flow velocity was about 0.27-0.50 m/s.

Mobile PULSE : A Routing Protocol Considering the Power and the Route Recovery Time in Sensor Networks with A Mobile Sink Node (모바일 PULSE : 모바일 싱크 노드를 가진 센서 네트워크에서의 경로 복구 시간과 전력 소모량을 고려한 라우팅 프로토콜)

  • Lee, Chi-Young;Lee, Shin-Hyoung;Yoo, Chuck
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.2B
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    • pp.151-161
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    • 2009
  • The PULSE protocol can greatly reduce power consumption using a node's sleep state. But this protocol does not consider movement of a sink node in a sensor network. In the mobile sensor network a routing protocol must recover path error by movement of a sink node as quickly as possible. Therefore we have to achieve fast path recovery and power saving to support movement of a sink node in a sensor network. This paper proposes the Mobile PULSE protocol which is a improved routing protocol for a mobile sink node. And we evaluate Mobile PULSE and show that the Mobile PULSE reduces the recovery time about 40% compared with original PULSE protocol. Mobile PULSE increases energy consumption than PULSE as a maximum of 0.8%, which means Mobile PULSE is similar to PULSE in energy consumption. This paper shows mobile PULSE's capability in the mobile sensor network through evaluation of path recovery time and power consumption.

2-dimensional Measurement of Arterial Pulse by Imaging Devices (촬상소자를 이용한 맥동의 2차원 계측)

  • Kim, Ki-Wang
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.12 no.2
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    • pp.8-17
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    • 2008
  • Objectives: For the traditional pulse diagnosis in Oriental Medicine, not only the pulse shape in time domain, but the width, length and depth of arterial pulse also should be measured. However, conventional pulse diagnostic systems have failed to measure the spatial parameters of the arterial pulse e.g. effective length of arterial pulse in the wrist. In fact, there are many ways to measure that kind of spatial features in arterial pulsation, but among them, the method using image sensor provides relatively cheap and simple way, therefore I tested feasibility of measuring 2-dimensional pressure distribution by imaging devices. Methods: Using widely used PC cameras and dotted balloons, the subtle oscillation of skin over the radial artery was recorded continuously, and then the displacement of every dot was calculated. Consequently, the time course of that displacements shows arterial pulse wave. Results: By the proposed method I could get pressure distribution map with 30Hz sampling rate, 21steps quantization resolution, and approximately 1mm spatial resolution. With reduced quantization resolution, $3cm{\times}4cm$ view angle could be achieved. Conclusion: Although this method has some limitations, it would be useful method for detecting 2-dimensional features of arterial pulse, and accordingly, this method provides a novel way to detect 'narrow pulse', 'wide pulse', 'long pulse', 'short pulse', and their derivatives.

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