• 제목/요약/키워드: a probe

검색결과 4,487건 처리시간 0.039초

생체내의 혈중이온농도 예측을 위한 마이크로 pH-ISFET프로브의 개발 (Development of a Micro pH-ISFET Probe for in vivo Measurements of the Ion Concentration in Blood)

  • 손병기;이종현;이광만
    • 대한전자공학회논문지
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    • 제23권1호
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    • pp.83-90
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    • 1986
  • A micro pH-ISFET probe, which can be applied to the in vivo measurements of the hydrogen ion concentration in blood, has been developed, and a measuring system equiped with this probe also developed. The pH-ISFET has been fatricated by employing the techniques of integrated circuit fabrication. Two kinds of micro electrode formed around the sensing gate during the wafer process, and the other is a capillary type of Ag/AfCl/sat. KCI reduced in size. This capillary electrode has shown its good performance characteristics so far in the application with ISFET as well as a commercial one. In order to form a micro pH-ISFET probe, this pH-ISFET and well as a commercial one. In order to form a micro pH-ISFET probe, this pH-ISFET and the capillary electrode were built together into a needle tip having 1 mm inner diameter. The chip size of a twin pH-ISFET is 0.8 mmx1.4 mm, the material of the sensing gate membrane is Si3N4, and the sensitivity of the developed probe is about 52mV/pH.

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인홀 시험을 이용한 터널 막장의 암반강성 측정에 대한 적용성 연구 (A Pilot Study of Stiffness Mesurements for Tunnel-Face Materials Using In-hole Seismic Method)

  • 목영진;김영수
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
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    • pp.445-456
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    • 2005
  • The research concentrates on improving the in-hole seismic probe, which has been developed in past five years, to be used in stiffness measurements of tunnel-face materials. The probe was down-sized to be fit in 45-mm diameter holes(or BX) drilled by a jumbo-drill, which is used to drill holes to install explosives for tunneling. Also trigger system was improved by using a down-speeding motor for operating convenience and air packing system was replaced with a set of plate-springs to eliminate supply of compressed air. These modifications are to adjust the probe for the unfavourable environment inside of tunnels and to test without any further drilling cost. The probe and testing procedure were successfully adopted with horizontal holes drilled by a jumbo-drill at a tunnel-face to evaluate the stiffness of rock mass. The measured shear wave velocities can be used to estimate deformation properties of rock mass for tunnel analyses.

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전자파 비흡수율(SAR) 측정용 전기장 프로브의 검파 전압 특성 (Characteristics of the Detection Voltages of an E-field Sensing Probe in SAR Measurement System)

  • 김윤명;이승배;김기회
    • 한국전자파학회논문지
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    • 제16권2호
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    • pp.217-221
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    • 2005
  • 이동통신 기기로부터 복사되는 전자파가 인체에 흡수되는 에너지의 양은 모의 인체 내에서 전자파 비흡수율 [SAR(Specific Absorption Rate)]로 평가된다. RF 센싱 프로브의 Schottky 다이오드에 검출된 DC 전압은 높은 레벨에서 자승법칙(Square Law) 영역을 벗어나 선형성을 나타낸다. Square Law Region을 벗어난 직선 영역의 검파는 적절한 DCP(Diode Compression Point) 값으로 검 파된 전압을 보상하여야 한다. 적절한 보상에 의한 한 점에서의 SAR 값은 200 W/kg까지 측정할 수 있다.

Spatial Information Transfer with a Stationary Coupling Wave in Rb Atoms

  • Bae, In-Ho;Moon, Han-Seb
    • Journal of the Optical Society of Korea
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    • 제12권3호
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    • pp.192-195
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    • 2008
  • We report on the spatial information of a coupling laser transfer into a reflected probe laser; the transfer is achieved by means of electromagnetically induced transparency through a common excited state connected with $5S_{1/2}-5P_{1/2}(F=1{\rightarrow}F'=2)$ in the $^{87}Rb\;D_1$ line. When the coupling laser was spatially modulated as a stationary wave, the absorption of the probe laser was enhanced and the reflection of the probe laser was generated. When the coupling laser was spatially modulated by a mask, we observed that the reflection light of the probe laser was modulated as the shape of the mask. The Bragg reflection transferred the spatial information of the coupling laser. The reflection was approximately 7% of the incident power of the probe laser.

Salmonella species 검출용 DNA Probe 분석시스템 고안

  • 이웅희;백세환
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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    • pp.711-712
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    • 2000
  • DNA probe assay comprising a microwell as' solid matrix for the immobilization of streptavidin (SA) and an oligonucleotide with covalently bound fluorecein as detection probe was developed. The insolubilized SA captured the biotinylated DNA product of polymerase chain reaction (PCR), and the product was denatured under a basic condition. The remaining single-stranded DNA on the solid surface was hybridized with the probe for signal generation that was performed based on enzyme-linked immuno -reactions.

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Atom Probe Tomography: A Characterization Method for Three-dimensional Elemental Mapping at the Atomic Scale

  • Choi, Pyuck-Pa;Povstugar, Ivan
    • 한국분말재료학회지
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    • 제19권1호
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    • pp.67-71
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    • 2012
  • The present paper gives an overview about the Atom Probe Tomography technique and its application to powder materials. The preparation of needle-shaped Atom Probe specimens from a single powder particle using focused-ion-beam milling is described. Selected experimental data on mechanically alloyed (and sintered) powder materials are presented, giving insight into the atomic-scale elemental redistribution occurring under powder metallurgical processing.

직류전위차법을 이용한 결함검출에 관한 연구 (A Study on Detecting Flaws Using DC Potential Drop Method)

  • 배봉국;석창성
    • 대한기계학회논문집A
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    • 제24권4호
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    • pp.874-880
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    • 2000
  • In this paper, a DC potential drop measurement system was used to find the position of the flaw on a simple thin plate. Four-point probe test was evaluated and used for this study. In the four-point probe test, the more distance between current pins provides the more measurable scope, the less voltage difference, and the more voltage difference rate. In the other hand, the more distance between voltage pins provides the less voltage difference and the less voltage difference rate. An optimized four-point probe was applied to measure the relation between voltage and the relative position of flaw to the probe. The Maxwell 21) simulator was used to analyze the electromagnetic field, and it showed that the analytical result was similar to the experimental result within 11.4% maximum error.

Neural Interface with a Silicon Neural Probe in the Advancement of Microtechnology

  • Oh, Seung-Jae;Song, Jong-Keun;Kim, Sung-June
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제8권4호
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    • pp.252-256
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    • 2003
  • In this paper we describe the status of a silicon-based microelectrode for neural recording and an advanced neural interface. We have developed a silicon neural probe, using a combination of plasma and wet etching techniques. This process enables the probe thickness to be controlled precisely. To enhance the CMOS compatibility in the fabrication process, we investigated the feasibility of the site material of the doped polycrystalline silicon with small grains of around 50 nm in size. This silicon electrode demonstrated a favorable performance with respect to impedance spectra, surface topography and acute neural recording. These results showed that the silicon neural probe can be used as an advanced microelectrode for neurological applications.

A Brief Comment on Atom Probe Tomography Applications

  • Seol, Jae-Bok;Kim, Young-Tae;Park, Chan-Gyung
    • Applied Microscopy
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    • 제46권3호
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    • pp.127-133
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    • 2016
  • Atom probe tomography is a time-of-flight mass spectrometry-based microanalysis technique based on the field evaporation of surface atoms of a tip-shaped specimen under an extremely high surface electric field. It enables three-dimensional characterization for deeper understanding of chemical nature in conductive materials at nanometer/atomic level, because of its high depth and spatial resolutions and ppm-level sensitivity. Indeed, the technique has been widely used to investigate the elemental partitioning in the complex microstructures, the segregation of solute atoms to the boundaries, interfaces, and dislocations as well as following of the evolution of precipitation staring from the early stage of cluster formation to the final stage of the equilibrium precipitates. The current review article aims at giving a comment to first atom probe users regarding the limitation of the techniques, providing a brief perspective on how we correctly interprets atom probe data for targeted applications.

Measurement of plasma potential by a biased cut off probe

  • 김대웅;김정형;성대진;유신재;장홍영
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
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    • pp.465-465
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    • 2010
  • Cut off probe, the efficient method, can measure the plasma parameters like the plasma electron density and the electron temperature. Plasma potential is also one of the important parameters in plasma processing but cannot be measured by cut off probe yet. Thus we developed method to measure plasma potential by focusing on relation between bias on a tip and sheath around tip. The system consist of a ICP(Inductive Coupled Plasma) source, a Network analyzer and a bias tee that can be bridge apply DC voltage on the cut off probe tip. Plasma potential is identified by using this system. The results corresponded well with the measured results by single langmuir probe(SLP).

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