• 제목/요약/키워드: length measurement

검색결과 2,195건 처리시간 0.034초

오리피스 유량계와 터빈 유량계의 직관부길이와 유동안정기에 관한 연구 (A Study of Straight Pipe Length and Straightener in Orifice Meter Turbine Meter)

  • 허재영;안승희;이강진;이승준
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2000년도 유체기계 연구개발 발표회 논문집
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    • pp.265-271
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    • 2000
  • Orifice meters and turbine meters are frequently used for measuring gas flow in gas industry. However, to insure the accuracy of the measurement, a certain length of the meter run at the upstream of the flow meter is required. The objective of this study is to analyze flow measurement errors of the orifice meter quantitatively for shorter lengths of the meter runs than those suggested in the standard manuals with variation of diameter ratio( $\beta$ ratio) and flow rate and also to analyze flow measurement errors of the turbine meter with and without straightener. The test results showed that the flow measurement errors of the orifice meter were inversely proportional to the diameter ratio. In other words, when the diameter ratio is 0.3 and 0.7, the measurement error is $-7.3\%$ and $-3.5\%$, respectively. the main reason of the measurement error is due to the swirl effect from the configuration of the meter run at the upstream of the flow meter. In case the length of the meter run is shorter than that suggested In the standard, the swirl effect is not removed completely and it affects the flow meter's performance. As mentioned above, the less the pipe diameter ratio, the mon the flow measurement error. It means that the swirl effect on the orifice meter increases as the $\beta$ ratio decreases.

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중년 여성의 자켓패턴 설계 (Jacket Pattern for Middle-Aged Women)

  • 류영숙;이정란
    • 한국의류산업학회지
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    • 제2권4호
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    • pp.353-359
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    • 2000
  • The purpose of this study was to develop the jacket pattern drafting method for Korean middle-aged women. The study was composed as follows : 1. Body measurement and statistical analysis : Two hundreds and forty four middle-aged women between the ages of forty five and fifty nine were measured on 52 items. 2. Development of new jacket pattern drafting method : Measurement items necessary to draft new jacket pattern were back waist length, bust girth, waist girth, hip girth, back interscye breadth, front interscye breadth, neck base girth, nipple length, nipple to nipple breadth, 1/2 posterior shoulder length and sleeve length. Basic jackets constructed from the experimental patterns were examined through the fitting test. 3. Evaluation of the new pattern drafting method : The sensory evaluations for appearance and comfort were applied to evaluate the new jacket pattern by comparing it with one of the conventional jacket patterns (Lee Hyung-Suk's). According to the result of sensory evaluation, the new jacket pattern was more positive.

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스크린 망사의 견장과 오프닝의 변화 (The Opening Size Change for Screen Tension)

  • 정기영;강영립
    • 한국인쇄학회지
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    • 제28권1호
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    • pp.43-50
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    • 2010
  • The 200mesh screen was tensioned and fixed on a frame. When applied tension to 5N and 10N per unit area, a side length of opening of the screen was 163.223${\mu}m$ and 168.224${\mu}m$, respective. But side length not tensioned was 158.879${\mu}m$. We knew that a side length of opening of the screen rarely changes with tension applied to the screen. The appearances that a side length of opening of the screen expand little are due to a decreasing diameter of thread by means of tension. In a thickness measurement of screen, While the high density mesh screen that had a lot of knots that crossed a line of latitude and longitude per unit area appeared a higher numerical value, the low density mesh screen that had a few knots appeared a low numerical value.

실배관 시험편의 균열 길이 측정에 관한 연구 (A Study on the Measurement of the Crack Length for the Real Scale Pipe Specimen)

  • 박재실;석창성
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.397-402
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    • 2003
  • Fracture resistance curves for concerned materials are required in order to perform elastic-plastic fracture mechanical analyses. Fracture resistance curve is built with J-integral values and crack extension values. The objective of this paper is to apply the load ratio method to the measurement of the crack length for the real scale pipe specimen. For these, the fracture test using the real scale pipe specimen and finite element analyses were performed. A 4-point bending jig was manufactured for the pipe test and the direct current potential drop method and the load ratio method was used to measure the crack extension and the length for the real scale pipe test. Finite element analyses about the compliance of the pipe specimen were executed for applying the load ratio method according to the crack length.

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MTF 방법에 의한 카메라 렌즈 초점 자동 측정 시스템 개발 (Focal Length Measurement System for Camera Lens using the MTF)

  • 이석원;이동성;박희재;문호균;김영식
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 춘계학술대회 논문집
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    • pp.264-270
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    • 1996
  • In this paper, a computer automated system has been developed for measuring the focal length of camera lens using the MTF(Modurar Transfer Function) based on the signal processing around a line CCD and autocollimator. An optical Path for the focal length measurement system has been designed around thelight sourec, collimator, camera, mirror and the line CCD. The eyepiece of the collimator is replaced byline CCD, and the mirror is moved along the focal axis by a PC driven step motor. An efficient method has been designed for finding the optimum MTF value for the focal length based on the least squares approach. The developed system is fullycomputer automated: signal transmission to and from the camera, MTF evaluation based on the line CCD, step motor contorl, etc. The developed system has been applied to a practical camera manufacturing process and demonstrated its performance

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시각적 판단에 의한 얼굴유형 분류와 계측 특성 연구 (A Study on Women′s Face Types Classification by Visual Distinction and Difference from the Measurement)

  • Namwon Moon
    • 복식문화연구
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    • 제8권1호
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    • pp.133-144
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    • 2000
  • The purpose of this study was to classify women's face types by visual distinction and to analyze the measurement of face types. A survey was conducted by subjects of 167 women's college students in Kwangju City and Chonnam area. Data were analyzed by Frequencies, Mean, one way ANOVA and Ducan's Multiple Range Test. The major results were as followed ; ·Women's face types were classified by 7 types and there were oblong shape(28.3%), egg shape(25.7%), round shape(23.9%), square shape(12.4%), inverted triangle shape(5.3%), diamond shape(3.5%), triangle shape(0.8%) in the subjects. ·From the measurements of the women's face, index of face length to face breadth was 1.38, it means that the index was different from the other refferences. And the lower face length was longer than the upper and the middle face lengths. ·Differences From those measurements like forehead breadth, face length/bizigion breath(p〈.001), bizigion breadth, bignathion slopper, stature(p〈.01) and trichion breadth, tragion-menton length(p〈.05) were significant in the classified face types.

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초음파 감쇠계수에 의한 균열길이의 측정 (Measurement of Crack Length by Ultrasonic Attenuation Coefficient)

  • 정남용;박성일
    • 대한기계학회논문집A
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    • 제28권4호
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    • pp.386-393
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    • 2004
  • In this paper, the ultrasonic attenuation coefficient was measured by variation of crack length for double-cantilever beam(DCB) specimen. The energy release rate, G, was obtained by the experimental measurement of compliance. The experimental results represents that the crack length for the ultrasonic attenuation coefficient and energy release rate is increases proportionally From the experimental results, we proposed a detecting method of the crack length by the ultrasonic attenuation coefficient and discussed it.

유방확대 수술환자 사진의 비율 측정치를 이용한 유방유형 분류 (Breast Type Classification of Breast Augmented Patients Using Photogrammetric Ratio Measurements(PRM))

  • 이경화;손부현
    • 패션비즈니스
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    • 제21권2호
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    • pp.61-77
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    • 2017
  • Although three-dimensional measurement systems for the human body have been studied, there is still an error between the measurements by the two-dimensional measurement method and the three-dimensional scanning method. Especially, in the case of the breast, the outline is not clear. The breast is made up of subcutaneous fat and mammary gland tissue, and it is easy to deform, making it difficult to grasp the exact shape. It is also more difficult to measure photogrammetry or three-dimensional measurement because it is difficult to obtain subjects because of the shame they are reluctant to expose. In this study, the angle and length of the line connecting the measurement points of the breast detail measurement items were compared with the unchanged measurement items such as breast width and center front length using the frontal and lateral photographs taken before and after breast enlargement surgery. The results of the study are as follows. The types of breast before and after surgery were classified into two groups and showed high accuracy rate. Therefore, it was possible to classify the breast type using the frontal and lateral views of the breast, and it was found that The PRM method can distinguish the characteristics of the breast type. Therefore, it can be useful for classifying and discriminating breast types.

Sliding-DFT에 기반한 전력선 위상 측정 기법 (Power-line phase measurement algorithm based on the sliding-DFT)

  • 안병선;김병일;장태규
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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    • pp.2192-2195
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    • 2003
  • This parer proposes a power-line phase measurement algorithm which is based on the recursive implementation of sliding-DFT. Usage of the single DFT coefficient in the conventional sliding-DFT based power-line phase measurement brings a significant error propagation when implemented in hardware with finite word-length arithmetic operations. The proposed algorithm utilizes all the N-point DFT coefficients in the recursion. Performance degradation caused by the finite word- length implementation of the algorithm is analyzed and verified with computer simulations. The robustness of the proposed phase measurement algorithm against the erroneous implementation is also confirmed by the performance analysis and simulation.

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Next Generation Fiber Length Measurement

  • Tiikkaja, Esa;Sopenlehto, Taina
    • 펄프종이기술
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    • 제32권5호
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    • pp.54-59
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    • 2000
  • The next generation fibre size analyser has been developed in Kajaani based on over 15 years experience in fibre measurement. This new FiberLab-analyser can measure fibre length both along the fibre centre line and as projected. The cross-sectional measurements of fibre are in principle similar to the earlier version FiberLab. Measured data are generally displayed in distributions. Some new calculations have been added, for example the fibres cross sectional area and fibre volume index both available as distributions as well. The performance of the FiberLab measurement is verified against the manual microscopic testing. These tests show that the new image analysis-based measurement well matches with the manual methods.

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