• Title/Summary/Keyword: Automatic measurement

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Automatic measurement of a Isolux diagram (등조도 곡선의 자동화 측정)

  • 권영혜;장우진
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 1989.10a
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    • pp.31-36
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    • 1989
  • Low-cost and automated isolux diagram measurement system are investigated. The system is constructed with illuminance measurement array, analog multiplexer, A/D converter and 16-bit microcomputer. The experimental results show good agreement with the measured illuminance values. Decreasing the measure-spacing, the more accurate diagram can be obtained.

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The Verification of Accuracy of 3D Body Scan Data - Focused on the Cyberware WB4 Whole Body Scanner - (3차원 인체 스캔 데이터의 정확도 검증에 관한 연구 - Cyberware의 WB4 스캐너를 중심으로 -)

  • Park, Sun-Mi;Nam, Yun-Ja
    • Journal of the Korea Fashion and Costume Design Association
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    • v.14 no.1
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    • pp.81-96
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    • 2012
  • The purpose of this study is to provide fundamental information for standardization of 3D body measurement. This research analyzes errors occurring in the process of extracting body size from 3D body scan data. First, as a result of analyzing basic state of the 3D body scanner's calibration, the point number of each section was almost the same, while the right and left as well as the front and back coordinates of the center of gravity are not, showing unstable data. Nevertheless, the latter does not influence on the size of cylinder such as width and circumference. Next, we analyzed point coordinates variations of scan data on a mannequin nude by life casting. The result was great deflection in case of complicated or horizontal sections including the reference point beyond proper distance from centers of four cameras. In case of the mannequin's size, accuracy proves comparatively high in that measurement errors in height, width, depth, and length dimension occurred all within allowable errors, only except chest depth, while there were a lot of measurement errors in a circumference dimension. Secondly, analysis of accuracy of automatic extraction identification program algorithm presented that a semi-automatic measurement program is better than an automatic measurement program. While both of them ate very acute in parts related to crotch, they are not in armpit related parts. Therefore, in extracting of human body size from 3D scan data, what really matters seems to parts related to armpits.

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Image Procession Algorithm For Antenna Extraction And Correction (안테나 추출및 보정을 위한 영상처리 알고리즘)

  • Kwak, Nae-Joung;Ryu, Sung-Pil;Song, Teuk-Seob;Kim, Sung-Min
    • The Journal of the Korea Contents Association
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    • v.9 no.12
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    • pp.546-555
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    • 2009
  • There is increasingly interested in the measurement of antenna's characteristics for one's manufacture according to one's various application. Due to this, the antenna measurement system need be made with more and more great precision. On measuring of the antenna's characteristic, the conventional system handled by human generates the error due to controlling the position of the system by user. Therefore there need be introduced the automatic measurement system of antenna's characteristic. In this paper, we propose antenna extraction algorithm for the Antenna automatic measurement system of antenna's characteristic. The proposed algorithm gets the antenna image from antenna measurement system, extracts an antenna object from the image, and extracts the parameters for antenna's slant and antenna's location. The extracted parameters is used to correct location and distortions of the antenna and automatic measurement. The proposed algorithm is applied to the patch antenna. The results show that antenna's object is efficiently extracted and the angle for correcting the error is calculated well.

An Automatic Focusing Method Using Establishment of Step Size from Optical Axis Interval (광학축 간격의 스텝크기 설정을 통한 오토포커싱 방법)

  • Kim, Gyung Bum;Moon, Soon Hwan
    • Journal of the Semiconductor & Display Technology
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    • v.14 no.1
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    • pp.7-11
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    • 2015
  • In this paper, an automatic focusing method has been proposed for speedy and reliable measurement and inspection in industry. It is very difficult to determine focusing step size and moving direction in one camera autofocusing. The proposed method can improve speed and accuracy of focusing by using the optical axis interval of two cameras, which is automatically set up as focusing step size. Also, it can determine moving direction from focus value comparisons of two cameras, and then solve ambiguity of one camera focusing. Its performance is verified by experiments. It is expected that it can apply to optical system for measurement and inspection in industry fields.

Automatic Contrast Enhancement by Transfer Function Modification

  • Bae, Tae Wuk;Ahn, Sang Ho;Altunbasak, Yucel
    • ETRI Journal
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    • v.39 no.1
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    • pp.76-86
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    • 2017
  • In this study, we propose an automatic contrast enhancement method based on transfer function modification (TFM) by histogram equalization. Previous histogram-based global contrast enhancement techniques employ histogram modification, whereas we propose a direct TFM technique that considers the mean brightness of an image during contrast enhancement. The mean point shifting method using a transfer function is proposed to preserve the mean brightness of an image. In addition, the linearization of transfer function technique, which has a histogram flattening effect, is designed to reduce visual artifacts. An attenuation factor is automatically determined using the maximum value of the probability density function in an image to control its rate of contrast. A new quantitative measurement method called sparsity of a histogram is proposed to obtain a better objective comparison relative to previous global contrast enhancement methods. According to our experimental results, we demonstrated the performance of our proposed method based on generalized measures and the newly proposed measurement.

A Hybrid Automatic Focusing Method with Gaussian Interpolation and Adaptive Step Size (가우시안보간과 적응스텝크기를 적용한 하이브리드 오토포커싱)

  • Moon, Soon Hwan;Kim, Gyung Bum
    • Journal of the Semiconductor & Display Technology
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    • v.13 no.1
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    • pp.51-55
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    • 2014
  • In this paper, an hybrid automatic focusing method has been proposed for speedy and reliable measurement and inspection in industry. It can improve reliability of focusing position by using not a focusing measure but the hybrid one that is incorporated with sobel operator and auto-correlation. Also, it can not only reduce control time of focusing position using adaptive step size, but also improve accuracy of focusing position by gaussian interpolation. Its performance is verified by experiments. It is expected that it can apply to optical system for measurement and inspection in industry fields.

Development of Rain Gauge and Observation Error (우량계 개발과 측정 오차)

  • 김대원;이부용
    • Journal of Environmental Science International
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    • v.11 no.10
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    • pp.1055-1060
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    • 2002
  • A new method of automatic recording raingauge is developed to measure rainfall 1200mm full scale with high accuracy and resolution. The principle of new instrument is to detect a weight change of a buoyant weight according to a change in water level of raingauge measured by the use of a strain gauge load cell. This method has the advantage of increasing measurement accuracy, since no moving equipment is used. Laboratory test of the instrument was recorded 0.4% error of 190mm rainfall amount. The validity of new instrument was examined by comparing its measured values with values recorded by automatic weather station on June 24 to 25 2001 at Daegu Meteorological Station, when there is 148.3mm rainfall amount. In spite of much rainfall there is only 0.77mm difference of total rainfall amount. This instrument was accomplished high accuracy and resolution at field test in much rainy day.

Inverse Boundary Temperature Estimation in a Two-Dimensional Cylindrical Enclosure Using Automatic Differentiation and Broyden Combined Method (자동미분법과 Broyden 혼합법을 이용한 2차원 원통형상에서의 경계온도 역추정)

  • Kim Ki-Wan;Kim Dong-Min;Baek Seung-Wook
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.3 s.246
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    • pp.270-277
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    • 2006
  • Inverse radiation problems were solved for estimating boundary temperature distribution in a way of function estimation approach in an axisymmetric absorbing, emitting and scattering medium, given the measured radiative data. In order to reduce the computational time fur the calculation of sensitivity matrix, automatic differentiation and Broyden combined method were adopted, and their computational precision and efficiency were compared with the result obtained by finite difference approximation.. In inverse analysis, the effects of the precision of sensitivity matrix, the number of measurement points and measurement error on the estimation accuracy had been inspected using quasi-Newton method as an inverse method. Inverse solutions were validated with the result acquired by additional inverse methods of conjugate-gradient method or Levenberg-Marquardt method.

Automatic modal identification and variability in measured modal vectors of a cable-stayed bridge

  • Ni, Y.Q.;Fan, K.Q.;Zheng, G.;Ko, J.M.
    • Structural Engineering and Mechanics
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    • v.19 no.2
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    • pp.123-139
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    • 2005
  • An automatic modal identification program is developed for continuous extraction of modal parameters of three cable-supported bridges in Hong Kong which are instrumented with a long-term monitoring system. The program employs the Complex Modal Indication Function (CMIF) algorithm for identifying modal properties from continuous ambient vibration measurements in an on-line manner. By using the LabVIEW graphical programming language, the software realizes the algorithm in Virtual Instrument (VI) style. The applicability and implementation issues of the developed software are demonstrated by using one-year measurement data acquired from 67 channels of accelerometers permanently installed on the cable-stayed Ting Kau Bridge. With the continuously identified results, variability in modal vectors due to varying environmental conditions and measurement errors is observed. Such an observation is very helpful for selection of appropriate measured modal vectors for structural health monitoring use.

A Study on the Classification of Neck-Base Circumference by Three-Dimensional Automatic Measurements of the Human Body - With the Focus on Women in their 20's - (3차원 인제 형상 데이터를 이용만 목밑둘레 유형화 연구 - 20대 여성을 중심으로 -)

  • Cho, Shin-Hyun;Seok, Hye-Jung
    • Journal of the Korean Society of Costume
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    • v.58 no.6
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    • pp.35-41
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    • 2008
  • The purposes of this study lied in the analysis and classification of neck-base circumference shapes of the women in their twenties, by the application of three-dimensional automatic measurement data of human body, and thereby in the understanding of neck-base circumference shapes by the classified type. The findings are as follows: 1. The comparison of three-dimensional human body measurement items relating to the neck-base circumference part of the women in their twenties indicated that the largest individual difference was found in cervicale-center-anterior neck radius than in other items. 2. The factor analysis, which was conducted to extract the factors constituting the neck-base circumference, showed the shape of cervicale(factor 1), the shape of section neck(factor 2), the thickness of neck(factor 3), the shape of anterior neck(factor 4), and the shape of side neck(factor 5). 3. The classification of the neck-base circumference shapes resulted in three types. Type 1 was the shape of a reverse triangle hanging forward, Type 2 was that of a circle, and Type 3 was that of an oval open to the sides.