• 제목/요약/키워드: Indirect Measurement

검색결과 443건 처리시간 0.029초

An Indirect Method to Monitor Plasma Status in a Transformer Coupled Plasma

  • 유대호;안승규;김지훈;장홍영
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.216-216
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    • 2011
  • There have been various direct or indirect methods to measure the characteristics of plasma. Comparing to direct method like Langmuir probe method, indirect measurements which give information as some external parameters like current, voltage, or phase are easier to obtain. In this research, an indirect method to measure averaged plasma density in a transformer coupled plasma(TCP) has been proposed and evaluated. With a simple analytic model connecting electrical characteristics to plasma impedance, direct measurement via double Langmuir probe has been performed. This result may play a meaningful role to diagnose TCP or similar plasma sources

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간접 매체로 전파된 AE신호 측정을 통한 효과적인 누설 검출기법 제시 (Presentation of the Efficient Leakage Detection by the Measurement of Indirect Media-Propagated AE Signal)

  • 이성재;김전하;강명창;김정석
    • 한국정밀공학회지
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    • 제21권9호
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    • pp.63-68
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    • 2004
  • The high pressure vessels that are constructed by welding process have many welding lines and most of the leakage defects are occurred on these welding lines. The acoustic emission(AE) technique has adopted to detect the defect location and leakage on welding parts, but the AE signal in leakage are incomplete due to the attenuation, reiteration, instability and limit of defect size. To overcome these troubles, the experiments in this study are conducted to measure the indirect media-propagated AE signal perpendicular to the leakage hole. The AE signals that are acquired from the direct and indirect media are analyzed, and the reliability of the indirect media-propagated AE signal are examined experimentally. By AE signal investigation, this method can be adopted to detect efficiently the leakage in welding parts.

석조문화재 풍화도 평가를 위한 초음파 측정의 설정과 직접-간접전달방법의 상관관계 (Establishment of Ultrasonic Measurement and Correlations of Direct-Indirect Method for Weathering Evaluation of Stone Cultural Heritage)

  • 이찬희;조영훈;전유근
    • 보존과학회지
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    • 제25권3호
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    • pp.233-244
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    • 2009
  • 이 연구에서는 석조문화재의 초음파 측정에 적합한 탐촉자 및 접촉매질을 선정하였으며, 과학적이며 정량적인 평가기술을 개발하기 위해 암종별 직접 및 간접전달방법의 상관관계를 분석하였다. 이 결과, 석조문화재에서 초음파 측정은 유형 3의 탐촉자(UTREXTX(RX)54kHz)와 접촉매질(고무찰흙)을 사용하는 것이 가장 적합한 것으로 나타났다. 또한 이 유형 3의 직접 및 간접전달방법의 보정계수는 화강암 1.50, 반려암 1.38, 석영섬록암 1.58로 산출되었다. 이 결과는 초음파탐사의 신뢰도를 높이기 위한 최초의 연구로서 석조문화재의 초음파탐사 방법을 확립하는데 크게 기여할 것으로 판단된다. 또한 암석의 표면요철도와 다양한 접촉매질을 고려한 보완연구가 수행되어야 할 것이며, 암종별 직접-간접전달방법의 상관관계에 대한 데이터베이스도 구축되어야 할 것이다.

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간접접촉 심전도 측정에서의 간접접촉 오른발 구동 접지 성능에 대한 연구 (A Study on Performance of Indirect-contact Driven-right-leg Ground in Indirect-contact ECG Measurement)

  • 임용규;김고근;박광석
    • 융합신호처리학회논문지
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    • 제9권4호
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    • pp.280-287
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    • 2008
  • 간접접촉 심전도(IDC-ECG) 측정에 공통 모드 잡음을 줄이기 위해 오른발 구동(Driven-right-leg) 접지 방법을 적용하고 그 접지의 성능을 조사하였다. 최근에 소개된 간접접촉 심전도 측정 기술은 전극과 인체 피부간의 직접 접촉이 필요하지 않기 때문에, 최근에 필요성이 대두되고 있는 가정에서의 장기간 무구속 심전도 측정에 적합한 측정방법으로서 현재 다양한 응용이 연구되고 있다. 그렇지만 간접접촉 심전도는 전원선에 의한 60Hz 잡음이 기존 측정 방법보다 크게 발생하여, 응용 범위의 확대에 제약 조건이 되고 있다. 본 연구에서는, 기존의 심전도 측정 방법에 사용되는 오른발 구동 접지 방법을 간접접촉 심전도 측정 방법에도 적용하여, 공통모드 잡음 성분을 반전 증폭하여 의자 좌판(seat)에 깔린 전도성 직물을 통해 인체에 feedback하였다. 이로써 피부와 직접 접촉이 없는 간접 접촉 방식의 오른발 구동 접지를 구현하였으며, 이 접지가 안정적으로 동작되고, 오른발 구동 이득이 약 1000정도에서 40dB 수준의 전원 잡음 감소 됨을 확인할 수 있었다. 이 연구의 결과로 간접접촉 심전도의 주파수 대역을 기존의 30Hz이하에서 100Hz 수준까지 높일 수 있게 되었으며, 접지 임피던스를 높일 수 있게 되어 간접접촉 심전도의 응용 분야를 더욱 넓힐 수 있게 되었다.

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청소년의 공격성 측정도구 개발: Ajzen의 계획된 행위 이론을 기반으로 (Development of an Aggression Scale for Adolescents: Based on Ajzen's Theory of Planned Behavior)

  • 장숙;안혜영
    • Child Health Nursing Research
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    • 제24권4호
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    • pp.484-495
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    • 2018
  • Purpose: This study was conducted to develop a scale for measuring aggression in adolescents, based on Ajzen's Theory of Planned Behavior (TPB). Methods: The participants were 38 adolescents in an in-depth study conducted to develop items for indirect measurement, 13 adolescents in a pre-test, and 289 adolescents in the present survey. The collected data were analyzed using content validity, the correlation coefficient, exploratory factor analysis, confirmatory factor analysis, reliability, and the Cronbach's ${\alpha}$. Results: In this study, the most important variable related to aggression was found to be aggression intention. This study included 4 factors of direct measurement and 6 factors of indirect measurement; therefore, 41 questions were developed. Increased levels of aggression were associated with higher scores for attitudes of aggression, subjective norms, perceived behavioral control, and aggression intention. Conclusion: We found that the questionnaire used in this study was valid and reliable as a measurement scale to explain aggression in adolescents based on TPB. Aggression intention should be included in aggression prevention programs because it was linked to aggressive behavior.

동적 지반물성측정장치(SIH, Soil Impact Hammer)의 국내 적용성 평가 (Investigation of Domestic Application for Soil Impact Hammer(SIH))

  • 박재영;석정우;황대진;양구승
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 가을 학술발표회 논문집
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    • pp.411-418
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    • 2002
  • In domestic road construction sites, the compaction control based on strength are widely performed through the direct method with high accuracy, such as Plate Loading Test or Field CBR test. It is impossible to manage all construction sites using the direct method because the direct method requires heavy reaction loads and long measurement time. Therefore, it is necessary to apply the indirect method that could control the relative density of construction sites on the whole. Indirect methods, such as Cone Penetration Test and Fall Cone Test, require extra time for data analyzing and fixed area for test device. In this paper, the field applicability of Soil Impact Hammer (SIH) was investigated comparing with the results of field measurement tests and laboratory compaction tests. SIH developed by Japan Construction Administration and Asanuma Ltd., is a kind of indirect methods for compaction checking. According to the results of SIH performed in domestic road construction site, the subgrade reaction modulus obtained from SIH are similar to that from Plate loading tests in the range of 10 to 40. In comparison with laboratory compaction test, similar compaction line are shown in the dry side of optimum moisture contents.

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3상 인버터의 DC 링크 커패시터 전류의 센서리스 측정 (Sensorless measurement of the DC link capacitor current of three-phase inverter)

  • 수효동;정영국;임영철
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2012년도 추계학술대회 논문집
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    • pp.205-206
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    • 2012
  • A general method to measure the inverter DC bus capacitor current is described. It is an indirect estimated method. By measuring the input and out voltage and current can calculate DC bus capacitor current. This paper will develope the theory that describes the indirect method. It will discuss and verify the feasibility of this approach through the use of the PSIM. Using SPWM control method will be simulated and compared.

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시각적 공간분할로 본 Dart 위치의 조형적 설계 (The plastic design of dart location from the viewpoint of visual-spatial division)

  • 정옥임
    • 대한인간공학회지
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    • 제6권1호
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    • pp.33-40
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    • 1987
  • To study the body trunk basic to Clothing construction, and study the peculiarities of visual spatial division, necessary items are measured indirectly from 216 unmarried women from 19 to 24 years old by a photographic net-work method. In so doing, the problem of Fashion Design in establishing the location of Darts for Basic Dress is not considered. The following results are obtained. 1) Indirect measuring method, is obtained approximate to actual size, with an error of .+-. 2.8cm. 2) In the modeling plan of Dart location viewed from the visual-spatial division in Basic Dress, it is concluded that Darts are to be placed at the point of 1/3k+1/5k form the waist. From the aesthetic point of wiew, it is more appealling for darts to be placed at the point of 6cm .+-. 0.6cm right or left of center. 3) From direct measurement dart location can be set based on bust point width, and from indirect measurement, dart location can be set based on waist width.

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디지털 카메라를 이용한 2D 인체계측법 연구 (A Study on a Measurement Method for 2D Anthropometry using Digital Camera)

  • 손희정;김효숙;최창석;손희순;김창우
    • 복식문화연구
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    • 제11권1호
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    • pp.11-19
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    • 2003
  • This study suggests the new 2D anthropometric method using digital camera. It is used MK2001 program that can convert 2D measurements to 3D measurements. To improve that it is measured 100 college students with direct and indirect anthropometric method. The measurements were processed by the SPSS ver10 Statistical Package. The average, standard deviation, and t-test were calculated for each category. Most measurements by 2D measurements are higher than direct measurements but degree. The difference between direct and indirect measurements is less than 2cm. In the results of t-test, height measurements including other 16 measurements which is easy to measure have no meaningful difference within 1cm. The depth measurements are most high difference. The result of each measurement proves that MK2001 program (2D anthropometry method using digital camera) is available for measuring the human body.

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절삭 공정의 2축 적응제어 (Adaptive Cutting force Control of 2Axes)

  • 조광섭;우중원;김종원
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 추계학술대회 논문집
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    • pp.653-657
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    • 1996
  • This paper presents adaptive cutting force control in milling process using indirect cutting force measurement. The cutting forces in X, Y, and Z axes are measured indirectly from the sensing current of the feed-drive servo motor. After modelling the feed-drive system of a horizontal machining center, the relation between the cutting force and the servo motor current is analyzed. The pulsating milling forces are measured from the sensing current within the bandwidth of the servo. It is shown that indirect cutting farce measurement can be used in adaptive cutting force control. The adaptive control scheme which is globally convergent and stable is attached to a commercial CNC machining center. Cutting experiments on end milling are performed for diagonal cutting.

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