• 제목/요약/키워드: Measuring technique

검색결과 1,773건 처리시간 0.041초

TLS 변위계측모델을 이용한 장스팬 철골 박스형 거더의 변위 계측 (Displacement Measurement of an Existing Long Span Steel Box-Girder using TLS(Terrestrial Laser Scanning) Displacement measurement Model)

  • 이홍민;박효선;이임평;권윤한
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2007년도 정기총회 및 학술발표대회
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    • pp.53-56
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    • 2007
  • It was previously introduced a new displacement measuring technique using terrestrial laser scanning (TLS) that remotely samples the surface of an object using laser pulses and generates the three-dimensional (3D) coordinates of numerous points on the surface. In this paper, for an assessment of the capabilities of the measuring technique about existing structures, the field tests for vertical displacement measurement of an existing long span steel box-girder are experimentally carried out. The performance of the technique is evaluated by comparing the displacements obtained from TLS system and displacements directly measured from linear variable displacement transducer (LVDT).

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스테레오 영상인식을 이용한 신관폭발고도 계측기술 (Measuring Technique for Height of Burst using Stereo-vision Recognition)

  • 강규창;최주호;박원우;황의성;홍성수;유준
    • 한국군사과학기술학회지
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    • 제2권1호
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    • pp.194-203
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    • 1999
  • This paper presents a measuring technique for bursting height of proximity fuses. This technique uses camera calibration to obtain the perspective transformation matrix describing the projection of the world coordinates to image coordinates, and calculates the world coordinates of bursting points from their image coordinates. The surface approximation algorithm by polynomial functions are also implemented.

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Hot strip 위치측정을 위한 Vision 기술 적용 (Applied machine vision technique in measuring the position of the hot steel strip)

  • 노경숙;이동원
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.1072-1075
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    • 1996
  • In hot rolling process at steel plant, cooling of the rolled strip at the exit of the rolling mill is one of the most important processes that would decide the quality of products. To guarantee the thermal equity over the strip, the device called an edge-masking unit is being used. That is installed between the strip and the sprayers to cover the side edge of the strip from spraying water. The accuracy of positioning the bracket is the key to this operation. A machine vision technique can be applied to measure the position of the side edges before an as-rolled strip enters into the cooling facility to rectify the error of preset position of the bracket. This paper shows the simulation result of applying the machine vision technique to measuring the position of a strip and suggests the solution for the target.

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2.75인치 로켓트 모터의 연소완료지표 계측기법 (Measuring Technique of Burn-out Indices for 2.75″ Rocket Motor)

  • 강규창;최주호;유준
    • 한국군사과학기술학회지
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    • 제3권1호
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    • pp.106-115
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    • 2000
  • This paper presents the measuring technique of time and velocity when rocket motor is burnt out for 2.751" rocket. This technique use doppler effect, frequency spectrum analysis and curve fitting. In this study, we use muzzle velocity radar for doppler signal acquisition, short-time fourier transform for spectrum analysis and curve fitting for smoothing.

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정밀가공면의 소성스트레인 측정을 위한 새로운 기법의 개발 (A New Technique Development for Measuring Plastic Strain of Precision Machined Surface)

  • 김태영;반야풍;문상돈
    • 한국정밀공학회지
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    • 제15권4호
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    • pp.141-147
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    • 1998
  • A plastically deformed layer in the precision machined surface affects in various forms the physical properties of machined components such as the fatigue strength, the dimensional instability, microcracks and the stress corrosion cracking. These physical properties, so called surface integrity, are very important for designing highly stressed and critically loaded components. Typical plastic strains in the precision machined surface are very difficult to measure, since they are located within a very short distance from the surface and they change very rapidly. A new way is suggested to determine the residual strain in plastically deformed materials by analyzing the plastically deformed layer after a subsequent recrystallization process. This investigation is to explore a new technique for measuring plastic strain in machining applications, and in particular, to and the effect of cutting parameters(rake angle, depth of cut, specific cutting energy), on the plastic strains and strain energy.

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교류전류를 이용한 결함탐상에 관한 연구 - 주파수와 Lift-off 효과 - (A Study on the Detection of Defects Using AC Current -The Effect of Frequency and Lift-off-)

  • 김훈;김정엽;문봉호
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집A
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    • pp.529-533
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    • 2001
  • NDI technique system using AC current is newly developed for inspection of defects. This technique is non-contact measurement system and can be applied for locating and sizing of surface defects in components. In this paper, the technique was applied for evaluating the location and size for 2-dimensional surface cracks and we had investigated the influence of frequency and lift-off. The results show that defects are able to detect with the variety of voltage, and the measuring voltage for the depth of defects are under the influence of the measuring frequency and the lift-off.

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적응기법을 이용한 전력계통의 주파수 측정 (An Adaptive Scheme for Frequency Measurement in Power System)

  • 박철원;남시복;신명철
    • 대한전기학회논문지:전력기술부문A
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    • 제51권3호
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    • pp.143-152
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    • 2002
  • Frequency is regarded as one of most important indices for the operating power systems. Several digital techniques for measuring frequency have been presented in the last decades. This paper proposes a design and implementation an adaptive scheme using phase angle difference calculation fort frequency measuring in power system. The advantages of the proposed technique are demonstrated by fault signals from EMTP simulation and user defined arbitrary signals by Excel program. The proposed technique is compared with the conventional methods. Performance teat results indicate that the proposed technique provides accurate measures in pretence of noise and harmonics and in case faults and is suitable for measurement near-nominal, nominal. and off-nominal frequencies. We can see that It will be useful in microprocessor based relays and digital metiers that need to measure power system frequency.

Mobile Application based on Image Processing and a Proportion for Food Intake Measuring

  • Kim, Do-Hyeon;Kim, Yoon;Han, Yu-Ri
    • 한국컴퓨터정보학회논문지
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    • 제22권5호
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    • pp.57-63
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    • 2017
  • In the paper, we propose a new reliable technique for measuring food intake based on image automatically without user intervention. First, food and bowl image before and after meal is obtained by user. The food and the bowl are divided into each region by the K-means clustering, Otsu algorithm, Morphology, etc. And the volume of food is measured by a proportional expression based on the information of the container such as it's entrance diameter, depth, and bottom diameter. Finally, our method calculates the volume of the consumed food by the difference between before and after meal. The proposed technique has higher accuracy than existing method for measuring food intake automatically. The experiment result shows that the average error rate is up to 7% for three types of containers. Computer simulation results indicate that the proposed algorithm is a convenient and accurate method of measuring the food intake.

수압 측정에 기반하는 요류검사의 정확도 검증 (Accuracy Validation of Urinary Flowmetry Technique Based on Pressure Measurement)

  • 최성수;이인광;김군진;강승범;박경순;이태수;차은종;김경아
    • 대한의용생체공학회:의공학회지
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    • 제29권3호
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    • pp.198-204
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    • 2008
  • Uroflowmetry is a non-invasive clinical test useful for screening benign prostatic hyperplasia(BPH) common in the aged men. The current standard way to obtain the urinary flow rate is to continuously acquire the urine weight signal proportional to volume over time. The present study proposed an alternative technique measuring pressure to overcome noise problems present in the standard weight measuring technique. Experiments were performed to simultaneously acquire both weight and pressure changes during urination of 9 normal men. Noise components were separated from volume signals converted from both weight and pressure signals based on the polynomial signal model. Signal-to-noise ratio was defined as the ratio of the energies between signal and noise components of the measured volume changes, which was 8.5 times larger in the pressure measuring technique, implying that cleaner signal could be obtained, more immune to noisy environments. When four important diagnostic parameters were estimated, excellent correlation coefficients higher than 0.99 were resulted with mean relative errors less than 5%. Therefore, the present pressure measurement seemed valid as an alternative technique for uroflowmetry.

Horn과 Anandan기법을 이용한 Optical flow 측정 (Measurement of optical flow using horn and anandan techniques)

  • 송석진;남기곤;이장명
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 하계종합학술대회논문집
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    • pp.685-688
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    • 1998
  • Measurement of optical flow is a core problem of matching through the analysis of image sequences. In this paper, horn's and anandan's techniques are analyzed to derive a better technique for matching. Experimental results show that Horn's technique has low accuracy in measuring the velocity of optical flow while anandan's technique has poor performaance for diverging images. Based upon this observation, a new technique for the measurement of optical flow is proposed.

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