• 제목/요약/키워드: Short Pulse

검색결과 551건 처리시간 0.03초

효과적인 단열 펄스 압축을 위한 분산감소 광섬유의 분산 특성 및 입력 펄스 진폭 결정 (Determination of the dispersion profile of a dispersion decreasing fiber and the input pulse amplitude for efficient adiabatic pulse compression)

  • 최봉수;서동선
    • 전자공학회논문지D
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    • 제34D권3호
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    • pp.123-130
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    • 1997
  • We determine the dispersion profile of a dispersion decreasing fiber(DDF) for optimum pulse compression from a trade-off between high pulse compression and low pedestal power/short DDF length. We find that the optimum vlaue of the exponential dispersion decreasing factor .alpha. is 0.95 and that the corresponding optimum fiber length is 1.5 times of the initial soliton period. Passing through the dDF, ~10 times of pulse comparession ratio can be achieved without significant increase in pedestal power. To compress relatively broad pulses using a given DDF optimized at a specific pulse width, we also detemrine the optimum input pulse amplitude, as a function of input pulse width.

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말초신경계 치료를 위한 미니 Loop - 코일 삽입형 자기치료기 (Mini loop coil magnetic curer for peripheral nervous system treatment)

  • 김휘영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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    • pp.49-51
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    • 2007
  • It is as result that study to apply mini magnet nerve curer in peripheral nervous system disease treatment. Design and embodied action power and Control Unit in cylinder form of magnet roof object firstly. Yielded service area about special quality of probe of roof object cylinder style and treatment area dimension and distance of treatment pulse secondly. Embody pulse forming course energy value by Probe's form by third, could embody treatment pulse by disease. Specially, through a special quality experiment, saved Damping pulse torn and treatment pulse form etc. variously. Lately, embodied this to aid a little in disease treatment that follow that there is no invasion that there is no stimulation by medicine development. Go amplitude treatment pulse (traditional magneto-therapy of greatly great that strong) does curative effect greatest at short time and becomes thought that demand is magnified greatly at the future in this research.

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소형트랜스의 Cascading 방식을 적용한 임펄스 출력특성 (The Impulse Output Characteristics using Cascading Method of Compact Transformer)

  • 정종한;김휘영;홍정환;박구렬;김희제;조정수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 C
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    • pp.1865-1867
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    • 2000
  • The pulse power system has been widely used to many applications. such as E/P(Electrostatic Precipitator), DeNOx/DeSOx power system, ozon generator. etc. A pulse energy efficiency for load depend on the rising time, peak value, pulse duration, impedance matching. etc. The pulse generator generally required for short pulse duration, high peak value was forced to consider its size and economy. In this study, developing a compact pulse generator that applied for Cascading method to be made of two pulse transformer, we compared cascading voltage with no cascading one by applying the pulse energy to load.

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후방 충돌 펄스와 NCAP 펄스 차이로 인한 목상해 특성 비교 (Compare Characteristics of Neck Injuries between Rear Impact Pulse and NCAP Pulse)

  • 김종곤;박종호
    • 자동차안전학회지
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    • 제9권3호
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    • pp.7-12
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    • 2017
  • The whiplash is the most important issue of low speed rear-impact. So auto makers are committed to developing a seat to improve whiplash injury. Most NCAP tests have been used by same pulse (Mid Velocity 16kph). Only Euro NCAP uses different pulse that consists of Low, Mid, High velocity. But Euro NCAP also uses same pulse in Mid velocity as other NCAP test. That Mid velocity NCAP pulse was made by rear impact that has 90's vehicle structure properties. That pulse was used until now days. However these days, auto maker use more high tensile steel than 90's as customer and society demand more fuel efficiency and light vehicle with good safety structure. So modern vehicles have different pulse patterns of rear impact than NCAP pulse and 90's vehicle crash properties. In this paper, the test was conducted by following condition. Target car was impacted by the rigid barrier with certain velocity. Finally target vehicle gained delta V 16kph which was same velocity as NCAP Mid Velocity pulse. It is critical velocity which occur long period neck injury. It is very different pulse that was gained by real car impact from NCAP pulse. And it has higher peak G with high fluctuation and short duration than NCAP pulse.

극초단파 레이저를 이용한 PI 필름 가공 기술개발 (Ultrashort pulse laser induced PI film scribing)

  • 김태동;이호
    • 한국산업융합학회 논문집
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    • 제20권4호
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    • pp.307-311
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    • 2017
  • Ultra short pulse laser processing with the PI (polyimide) substrate is conducted to increase flexibility and radius of curvatures. A femtosecond laser is used to perform micro machining by minimizing the heat effect in PI substrate. The laser processing according to the parameters, such as fabricated line width, depth, laser power, distance between lines, is carried out to understand the characteristics of fabricated lines. A bending test is carried out to evaluate bending shapes and the radius of curvature after bending and spreading it 1000 times. The results demonstrates that the radius of curvature decreases in deepen lines and increases with the augment of the number of the fabricated lines, and distance between lines.

Analysis of an AC/DC Resonant Pulse Power Converter for Energy Harvesting Using a Micro Piezoelectric Device

  • Chung Gyo-Bum;Ngo Khai D.T.
    • Journal of Power Electronics
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    • 제5권4호
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    • pp.247-256
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    • 2005
  • In order to harvest power in an efficient manner from a micro piezoelectric (PZT) device for charging the battery of a remote system, a new AC/DC resonant pulse power converter is proposed. The proposed power converter has two stages in the power conversion process. The first stage includes N-type MOSFET full bridge rectifier. The second stage includes a boost converter having an N-type MOSFET and a P-type MOSFET. MOSFETs work in the $1^{st}$ or $3^{rd}$ quadrant region. A small inductor for the boost converter is assigned in order to make the size of the power converter as small as possible, which makes the on-interval of the MOSFET switch of the boost converter ultimately short. Due to this short on-interval, the parasitic junction capacitances of MOSFETs affect the performance of the power converter system. In this paper, the performance of the new converter is analytically and experimentally evaluated with consideration of the parasitic capacitance of switching devices.

여성 불임환자의 맥진특성 연구 (A Study on Characteristics of Pulse Diagnosis in Infertile Women)

  • 유정은;장새별;유동열
    • 혜화의학회지
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    • 제23권2호
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    • pp.15-21
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    • 2015
  • Objective : The purpose of this study is to demonstrate the characteristics of pulse diagnosis in infertile women. Methods : We have studied 38 women infertility patients in the Dunsan oriental hospital by using pulse diagnostic device. Pulsation and pulse types have been analyzed with variables of infertility factors. Statistical analysis was performed by adopting descriptive and inferential tests. Results : Both right and left chi parts were shown different from other parts. In small intestine and gall bladder showed significantly different pulsation according to the infertility factor. Short pulse, fine pulse, skipping pulse, shallow pulse and deep pulse were often representative pulse types for the main organs of woman infertility. In Triple energizers showed significantly different shallow pulse type according to the infertility factor. Conclusion : The results corresponded closely with previous literature on pulse diagnosis about infertile women.

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IR-UWB 시스템을 위한 채널 추정 기법 (An overview of channel estimation for IR-UWB System)

  • 신창택;최진규
    • 한국인터넷방송통신학회논문지
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    • 제10권3호
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    • pp.1-10
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    • 2010
  • IR (impulse radio)를 사용하는 IR-UWB 방식은 짧은 펄스를 전송하기 때문에 송수신기를 간단히 구현할 수 있고, 저 전력으로 구현 가능하며, 다중 경로 지연과 같은 외부 환경에 강한 특성을 가진다. 더불어, 짧은 펄스를 사용하므로 데이터 수신시 채널의 특징을 파악하기 위해 정확한 채널 추정 방법이 요구 된다. 채널 추정한 후 추정된 채널 이득과 지연 값은 레이크 수신기의 경로 선택에 이용되고, 데이터 수신시 파라메타를 정확히 찾는 정도에 따라서 성능이 좌우된다. 본 문서에서는 수신된 프리엠블 등의 신호를 이용하여 채널의 특성을 파악하여 관련 파라메터를 추출하는 채널 추정 알고리즘 및 다양한 관련 기술에 대하여 소개한다.

Nd:YAG 레이저의 펄스 제어에 의한 마그네슘 합금 용접부의 결함 방지에 관한 연구 (Study of Defect Prevention on Weld Zone of Magnesium Alloy by Pulse Control of Nd:YAG Laser)

  • 김종도;이정한;김장수
    • 한국정밀공학회지
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    • 제27권1호
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    • pp.99-104
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    • 2010
  • Magnesium and magnesium alloys, the lightest structural materials, have been received plenty of global attention recently. These alloys could be applied in various fields, especially the electronics industry, because of their excellent electromagnetic interference shielding. However, the welding technique of magnesium alloys has not been established. This study is related to the welding of AZ31B magnesium alloy by a short-pulsed a Nd:YAG laser. Two types of pulse waves, square pulse and variable pulse, were used to control weld defects. Results show that the crack and porosity, generated in the weld, had not been controlled by general square pulse. But through the application of variable pulse, the defects could be prevented and the good weld zone was obtained.

일정 전기자극하의 근력 상승 - 전기 자극 파형의 펄스 진폭과 펄스폭에 대한 의존성 (Muscle force potentiation during constant electrical stimulation - Dependence on pulse-amplitude and pulse-duration of electrical stimulation)

  • 김지원;강민영;공세진;엄광문
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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    • pp.2155-2156
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    • 2006
  • The purpose of this work is to investigate the fundamental properties of the gradual muscle force potentiation for the prediction of muscle force and body movement from the stimulation input with musculo-skeletal model. We investigated the dependence of force potentiation on both the pulse-amplitude and the pulse-duration. The experimental result showed that the force increment ratio during electrical stimulation decreased with pulse-amplitude. The force increment ratio decreased with short pulse-duration and was maintained to be constant with pulse-duration longer than $500{\mu}s$. A new model of the muscle potentiation based on these results is desired in the future.

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