• 제목/요약/키워드: Techique

검색결과 64건 처리시간 0.02초

Digital변별기를 이용한 고속A/D변환기 (A Fast A/D Converter using Digital Discriminators)

  • 이병수;이종악
    • 한국통신학회논문지
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    • 제7권3호
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    • pp.125-129
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    • 1982
  • 數MHz의 대역폭을 갖는 표준 주파수 대역폭의 애널로그(analogue) 신호를 8it) 정도의 디지틀(digital)신호로 정확하게 변환할 수 있는 대부분의 A/D변환기는 구성이 복잡하고 값도 고가이다. 따라서 본 논문에서는 전압제어 발진기(voltage-controlld oscillator)와 디지틀 판별기를 사용하여 간단한 고속 디지틀 變換機를 구성함으로써 종래의 고속 A/D 변환기에서 사용되어 오던 복잡한 論理回路를 제거하여 속도를 개선함과 동시에 회로의 단순화에 따른 경제적인 실리를 기하였다. 이 방법은 음성이나 영상신호를 8비트의 정도의 2진 부호로 변환 전송하는데 적합할 것이다.

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임피던스 심장기록법을 이용한 심장기능의 측정 (Measurement of Cardiac Function using Impedance Cardiography)

  • 김덕원;김정열
    • 대한의용생체공학회:의공학회지
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    • 제9권1호
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    • pp.109-116
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    • 1988
  • In this paper, principles of impedance tenchinque and relationship between stroke volume and impedance change were theoretically explained. An impedance cardiograph was designed and constructed. Its reproducibility was verified by experiment. Until now, the peak point of dZ/dt waveform, first derivative of impedance change(${\Delta}$Z) , has been detected by software technique requiring considerable time to process. However in this paper its peak point was found using hardware for saving processing time. Useful cardiac parameters such as stroke volume and contractility of cardiac muscle were measured noninvasively. The reproducibility of the instrument was measured to be better(less than 10%) than that of clinical standard method such as thermodilution (more than 30%). Hence impedance cardiography was found to be better techique for monitoring stroke volume and myocardial contractility for pre and post operation, and pharmacological studies.

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고체상 미량분석법(SPME)을 이용한 GC/FID에서의 BTEX 및 TCE 동시 분석

  • 이재선;장순웅;이시진
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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    • pp.405-408
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    • 2003
  • The soild phase microextraction(SPME)fiber which contains 100${\mu}{\textrm}{m}$ polydimethyl siloxane of a stationary phase was used for the analysis of volatile organic compounds contained in aqueous solution. volatile organic compounds, which were spiked in blank water and extracted by the headspace SPME techique, were analyzed by gas chromatography/flame ionization detector(GC/FID). The optimu condition of SPME fiber is determined that the analytes were extracted for 40min from extracts by using PDAfS100${\mu}{\textrm}{m}$ fiber. This new method could have wide application for the analysis of VOCs in aqueous solution.

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전압안전도해석을 위한 상정사고스크린닝에 관한 연구 (A Study of Contingency Screening Method for Voltage Security Analysis.)

  • 송길영;김영한;최상규
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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    • pp.879-882
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    • 1988
  • This paper describes a fast security analysis techique for voltage security assessment. The new method identifies the location of buses with potential voltage problems and thereby defines a voltage-sensitive subnetwork for contingency screening. The efficieny of this method is derived from the use of a voltage subnetwork to drastically reduce the number of bus voltages to be solved; and subsequently from the use of compensation techniques and sparse-vectors methods for screening. Results demonstrating the effectiveness of the method on the IEEE-14 bus model system are presented.

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기존 철근콘크리트 골조의 리모델링을 위한 내진보강 기술의 구조성능 평가 및 개선 (Improvement and Evaluation of Earthquake Resistant Retrofit Techiques for Remodeling of Structural Performance in Existing Reinforced Concrete Frames)

  • 하기주;신종학;이상목
    • 한국구조물진단유지관리공학회 논문집
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    • 제5권2호
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    • pp.175-182
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    • 2001
  • Five reinforced concrete frames were constructed and tested to study the structural performance of retrofitting effect reinforced concrete frame during and load revesals simultaneously. All specimens were modeling in one-third scale size. Experimental research was carried out to develop and evaluate the hysteretic behavior of reinforced concrete frame designed by high performance techniques, using carbon fiber plate, ALC panel, steel plate system with or without stiffener. Experimental programs wore carried to evaluate the structural performance of such test specimens, such as the hysteretic behavior, the maximum horizontal strength, crack propagation, and ductility etc. Specimens(RFCP, RFAR, RFSR, RFSR-S), designed by the improvement of earthquake-resistant performance, were attained more load-carrying capacity, energy dissipation capacity, and stable hysteretic behavior.

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CONTRIBUTION OF DIFFERENT TYPES OF $Ca^{2+}$ CHANNELS TO CATECHOLAMINE SECRETION IN RAT CHROMAFFIN CELLS

  • Goo, Yong-Sook;Jina Roh;Lee, Jung-Hwa;Cha, Eun-Jong
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 1996년도 정기총회 및 학술발표회
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    • pp.42-42
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    • 1996
  • Adrenal chromaffin cells secrete catecholamine in response to acetylcholine. The secretory response has absolute requirement for extracellular calcium, indicating that $Ca^{2+}$ influx through voltage operated $Ca^{2+}$ channels (VOCC) is the primary trigger of the secretion cascade. Although the existence of various types of $Ca^{2+}$ channels has been explore using patch clamp techique in adrenal chromaffin cells, the contribution of different types of $Ca^{2+}$ channels to catecholamine secretion remains to be establised. (omitted)omitted)

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인지질막의 유전완화 특성 (Dielectric Relaxation Characteristics of Phospholipid Membrane)

  • 이경섭;조수영;박석순;정헌상;최영일
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.173-176
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    • 1998
  • We experimentally investigated the dielectric relaxation phenomena of a liquid crystal monolayers by the Displacement current techique and displacement current flowing across monolayers is analyzed using rod-like molecular model. It is revealed that the dielectric reaxation time $\tau$ of monolaters in the isotropic polar orientational phase is determined using a linear relashionship between the monolayers compression speed $\alpha$ and the molecular area. The dielectric relaxation time of phospholipid monolayers was examined on the basis of the analysis developed here.

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집합주거단지에서 건강환경 조성을 위한 주거동의 배치유형이 통풍계획에 미치는 영향 분석 (The Effect of Layout Type of the Housing on Wind Flow Planning for Healthy Environment in Multi-Family Housing)

  • 조철희;이특구
    • 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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    • 제10권2호
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    • pp.71-82
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    • 2004
  • The purpose of this study is to analyze the wind velocity ratio in respect of layout types of housing in multi-family housing. The wind velocity ratio is a difference of wind velocity between on the leeward and on the windward side of multi-family housing. The layout types of housing are grid layout pattern of linear type, mixture pattern of Linear type + tower type and layout pattern of tower type. The planning of wind flow is an induced technique to increase in wind velocity in the city and multi-family housing. This study investigates wind velocity ratio into layout types of housing. consequently, analysis were basic design data for the planning techique of wind flow suggested.

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강유전성 고분자 P(VDF-TrFE) LB박막의 전기광학 특성 (The Electro-Optic Properties of Ferroelectric P(VDF-TrFE) LB Films)

  • 곽은휘;정치섭
    • 한국전기전자재료학회논문지
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    • 제23권7호
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    • pp.566-570
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    • 2010
  • Electro-optic modulators based on 25 monolayer langmuir-blodgett films of vinylidene fluoride and trifluoroethylene, P(VDF-TrFE), were fabricated. The LB films were prepared by transferring the monolayers on to an ITO coated glass with a surface pressure of 5 dyne/cm by use of the langmuir-schaefer deposition method. Measurement of the electro-optic coefficient has been carried out using a simple reflection techique. The E/O coefficient was found to be 154.9 pm/V and that value remained stable for at least 50 days.

A quantitative analysis about microleakage of all-in-one adhesive

  • Kang, Yong-Hee;Shin, Dong-Hoon
    • 대한치과보존학회:학술대회논문집
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    • 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
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    • pp.574-574
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    • 2003
  • I. Objectives Newly all-in-one adhesives were developed for reducing the techique sensitivity and chair time, but lots of concerns were made on bondability, longevity, and microleakage. The object of this study was to measure micro leakage and marginal quality of all-in-one adhesives using electrochemical method and SEM analysis quantitatively. II. Materials and Methods After making Class V cavities, they were bulk filled with Heliomolar(#A1) after surface treatment with three adhesives:Adper Prompt (Group 1), One up bond F (Group 2), Xeno III(Group 3).(omitted)

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