• 제목/요약/키워드: Park Se-Mu

검색결과 416건 처리시간 0.026초

FES 보행을 위한 휴대용 보행 이벤트 검출 시스템 (Portable Gait-Event Detection System for FES Locomotion)

  • 공세진;김철승;박관용;엄광문
    • 대한전기학회논문지:시스템및제어부문D
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    • 제55권5호
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    • pp.248-253
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    • 2006
  • The purpose of this study is to develop a portable gait-event detection system which is necessary for the cycle-to-cycle FES(functional electrical stimulation) control of locomotion. To make the system portable, we made following modifications in the gait signal measurement system. That is, 1) to make the system wireless using Bluetooth communication, 2) to make the system small-sized and battery-powered by using low power consumption ${\mu}$ P(ATmega8535L). The gait-events were analyzed in off-line at the main computer using ANN(Artificial Neural Network). The Proposed system showed no mis-detection of the gait-events of normal subject and hemiplegia subjects. The performance of the system was better than the previous wired-system.

CFC 대체물질을 이용한 GaAs의 레이저 유도 에칭 (Laser-induced etching of GaAs with CFC alternatives)

  • 박세기;이천;김무성
    • E2M - 전기 전자와 첨단 소재
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    • 제9권3호
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    • pp.240-245
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    • 1996
  • Non-ozone layer destructive Chlorofluorocarbon(CFC) altematives(CHCIF$_{2}$ and $C_{2}$H$_{2}$F$_{4}$) have been initially used for laser-induced thenrmochemical etching of GaAs. High etching rate up to 188.mu.m/sec and an aspect ratio of 2.7 have been achieved by a single scan of laser beam, respectively. The etching rate at constant ambient gas pressure was found to saturate for beam power. The chemical compositions of the reaction products deposited on the etched groove were measured by Auger electron microscopy(AES). Etched profile, depth and width were observed by scanning electron microscope(SEM).

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Capsaicin Inhibits Phospholipase C-coupled Signaling via the Capacitative $Ca^{2+}$ Entry in PC12 Cells

  • Park, Se-Young;Kim, Kyong-Tai
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 1998년도 학술발표회
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    • pp.30-30
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    • 1998
  • The effects of capsaicin on phospholipase (PLC)-induced capacitative $Ca^{2+}$ entry (CCE) were investigated in PC12 cells. Capsaicin inhibited one of PLC-linked signal, extracellular ATP-induced norepinephrine secretion with a concentration range, 10-100 $\mu$M. Capsaicin did not inhibit the peak portion of extracellular ATP-mediated [Ca$^{2+}$]i rise, but it recovered more rapidly to the normal level of [Ca$^{2+}$]i from the sustained [Ca$^{2+}$]i level.(omitted)ted)

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UV-laser 조사에 따른 폴리머 상부 클래드 광도파로 브래그 격자의 파장 변화 (The wavelength shift of waveguide Bragg grating with its polymer overclad irradiated by UV-laser)

  • 박동영;최기선;윤재순;백세종;문형명;김진봉;김광택;임기건
    • 한국광학회:학술대회논문집
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    • 한국광학회 2007년도 동계학술발표회 논문집
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    • pp.221-222
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    • 2007
  • The UV laser trimming can be useful to have an accurate performance specification of the passive waveguide devices. In order to measure the change of the refractive index of polymer overclad layer under the irradiation of uv light in a high precision Bragg grating is fabricated on the silica core of planar waveguide and the corresponding transmittance spectrum was analyzed. An effective refractive index change of $4.7x10^{-5}$ was obtained for a straight waveguide when its $60{\mu}m$-thick overclad was irradiated by UV laser pulses of its total fluence 24 $J/cm^2$.

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금속 슬릿 주변에 유전체 chirped grating을 배열함으로써 구현한 beam focusing (Beam focusing by a single subwavelength metal slit surrounded by chirped dielectric surface gratings)

  • 김세윤;박정현;임용준;김휘;이병호
    • 한국광학회:학술대회논문집
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    • 한국광학회 2007년도 하계학술발표회 논문집
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    • pp.255-256
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    • 2007
  • We propose a novel method for the beam focusing by a single subwavelength metal slit surrounded by chirped dielectric surface gratings. In the proposed method, the period of each grating is chirped to make a focused beam at the desired position. Design of the grating structures for optimal beam focusing and the analysis of the field distribution are conducted based on the rigorous coupled wave analysis (RCWA). It is shown that the focused beam is formed at 1.5${\mu}m$ from the metal substrate and its full width at half maximum (FWHM) is 411nm.

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Gas 이송용 Utility Materials의 전해연마 특성에 관한 연구 (A Study on the Characteristics of Electro-Polishing and Utility Materials for Gas Transitting)

  • 안세원;이종형;박무수
    • 한국기계가공학회지
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    • 제3권3호
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    • pp.52-57
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    • 2004
  • Many kinds of gases, such as erosion gas, dilution gas, and toxic gas have been used in manufacturing process of LCD at semiconductor. In order to increase accumulation rate of manufacturing process, high degree of purity in these gases and minimized metalllic dust are required. All wetted stainless steel surface must be 316L electro-polished with $0254{\mu}m$ in average. Based on the AES analysis, Cr/Fe 11 and $Cr_2O_3$ thickness $25{\AA}$ are measured Molybdenum and silicon contaminants which is characteristic of stainless steel and oxygen were found on the surface.

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전자빔 리소그래피와 열처리를 이용한 탄소 나노구조물의 제작 및 바이오센싱 응용연구 (Fabrication of carbon nanostructures using electron beam lithography and pyrolysis for biosensing applications)

  • 이정아;이광철;박세일;이승섭
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1727-1732
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    • 2008
  • We present a facile, yet versatile carbon nanofabrication method using electron beam lithography and resist pyrolysis. Various resist nanopatterns were fabricated using a negative electron beam resist, SAL-601, and were then subjected to heat treatment in an inert atmosphere to obtain carbon nanopatterns. Suspended carbon nanostructures were fabricated by wet-etching of an underlying sacrificial oxide layer. Free-standing carbon nanostructures, which contain 122 nm-wide, 15 nm-thick, and 2 ${\mu}m$-long nanobridges, were fabricated by resist pyrolysis and nanomachining processes. Electron beam exposure dose effects on resist thickness and pattern widening were studied. The thickness of the carbon nanostructures was thinned down by etching with oxygen plasma. An electrical biosensor utilizing carbon nanostructures as a conducting channel was studied. Conductance modulations of the carbon device due to streptavidin-biotin binding and pH variations were observed.

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정저항형 유속/유량 센서의 구조 및 회로 개선 연구 (Development of Sensor Structure and Operating Circuit for Constant Resistive Type Flow Velocity/Mass Sensor)

  • 강윤석;박세광
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1994년도 하계학술대회 논문집 C
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    • pp.1339-1341
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    • 1994
  • In this paper, the flow velocity/mass sensor which is based on the principle of CCT(Constant Chip Temperature) and its digital operating circuit and system have been developed and tested. The experimental result for flow velocity shows that the sensitivity is $644.01{\mu}W^2/[m/sec]$ for air, and there is nearly no hysteresis for full measured range of velocity. Response tine is between 1 second and 8 seconds for low and large velocity variation, respectively.

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