• 제목/요약/키워드: measure of an angle

검색결과 483건 처리시간 0.024초

Manipulability Analysis of a New Parallel Rolling Mill Based upon Two Stewart Platforms

  • Lee, Jun-Ho;Hong, Keum-Shik
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.107.5-107
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    • 2002
  • In this paper, a kinematic optimal design of a new paralleltype rolling mill based upon two Stewart platforms manipulator is investigated. The objective of this new parallel-type rolling mill is to permit an integrated control of the strip thickness, strip shape, pair crossing angle, uniform wear of the rolls, and tension of the strip. A manipulability measure, as the ratio of the manipulability ellipsoid volume and the condition number of a split Jacobian matrix, is defined. Two kinematic parameters, the radius of the base and the angle between two neighboring joints, are optimally designed by maximizing the global manipulability measure in the entire workspace.

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PMSM Angle Detection Based on the Edge Field Measurements by Hall Sensors

  • Kim, Jae-Uk;Jung, Sung-Yoon;Nam, Kwang-Hee
    • Journal of Power Electronics
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    • 제10권3호
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    • pp.300-305
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    • 2010
  • This paper presents a two Hall sensor method for rotor angle detection in permanent magnet synchronous motors (PMSM). To minimize the implementation complexity, the system is designed to measure the edge field of permanent magnet pieces. However, there are nonlinearities in the measured values of the edge field. In this work, an angle correction algorithm is proposed, and the improvements in accuracy are verified through experiments. Finally, a field orientation controller is constructed with the proposed angle detection algorithm.

Development of an Automatic Measuring Program for the Pennation Angle Using Ultrasonography Image (초음파 영상 깃각 자동 측정 프로그램 개발)

  • Kim, Jongsoon
    • Journal of The Korean Society of Integrative Medicine
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    • 제5권1호
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    • pp.75-83
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    • 2017
  • Purpose : The parameters used in architectural analysis are muscle thickness, fascicle length, pennation angle, etc. Pennation angle is an important muscle characteristic that plays a significant role in determining a fascicle's force contribution to movement. Ultrasonography has been widely used to obtain the image for measurement of a pennation angle since it is non-invasive and real-time. However, manual assessment in ultrasonographic images is time-consuming and subjective, making it difficult for using in muscle function analysis. Thus, in this study, I proposed an automatic method to extract the pennation angle from the ultrasonographic images of gastrocnemius muscle. Method : The ultrasonographic image obtained from 10 healthy participants's gastrocnemius muscle using for developed automatic measuring program. Automatic measuring program algorithm consists with preprocessing, line detection, line classification, and angle calculation. The resulting image was then used to detect the fascicles and aponeuroses for calculating the pennation angle with the consideration of their distribution in ultrasonographic image. Result : The proposed automatic measurement program showed the stable repeatability of pennation angle calculation. Conclusion : This study demonstrated that the proposed method was able to automatically measure the pennation angle of gastrocnemius, which made it possible to easily and reliably investigate pennation angle more.

Reliability and Validity of Measurement Using Smart Phone-Based Goniometer on Pelvic Tilting Angle in Standing and Sitting Position

  • Ha, Sung-Min;Jeon, In-Cheol
    • The Journal of Korean Physical Therapy
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    • 제31권1호
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    • pp.35-39
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    • 2019
  • Purpose: The purpose of this study was to assess the intra-rater and inter-rater reliability and validity of pelvic tilting angle measurements using a smart phone-based inclinometer (Clino) compared to a palpation meter (PALM) in the standing and sitting position. This study used an interchangeable method with Clino to measure the pelvic tilting angle in the standing and sitting positions. Methods: Twenty healthy subjects were recruited. Measurements of the pelvic tilting angle in the standing and sitting positions were obtained by two examiners using the Clino and PALM. A resting session was conducted 10 minutes later to assess the intra and inter rater reliability. To assess validity of the measurement using Clino, a PALM was used as the gold standard. The intra-class correlation coefficient (ICC) was used to determine the intra and inter rater reliability of Clino and a PALM. To assess the validity, the Pearson correlation coefficients were used for two measurement techniques to measure the pelvic tilting angle in the standing and sitting positions. The statistical significance was set to ${\alpha}=0.05$. Results: Measurements of the pelvic tilt had high inter-rater reliability in the standing (ICC=0.82) and sitting (ICC=0.88) positions using Clino and intra-rater reliability in the standing (ICC=0.87) and sitting (ICC=0.91) positions using Clino. Measurements of the pelvic tilt had high validity by a comparison of PALM and Clino in the standing (r=0.83) and sitting (r=0.89) positions (p<0.05). Conclusion: The use of Clino can be recommended as a tool to replace the PALM and measure the pelvic tilt angle in the standing and sitting positions while maintaining the clinical reliability and validity.

A Study on Digital Image Processing Algorithm for Area Measurement of an Object Image by the Hierarchical Angle-Distance Graphs (계층적 각-거리 그래프를 이용한 물체 면적 측정을 위한 디지털 영상처리 알고리즘에 관한 연구)

  • Kim Woong-Ki;Ra Sung-Woong;Lee Jung-Won
    • The KIPS Transactions:PartB
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    • 제13B권2호
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    • pp.83-88
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    • 2006
  • Digital image processing algorithm was proposed to measure the area inside of an object image using angle-distance graph used to analyze the pattern of an object in the digital image processing techniques. The first angle-distance graph is generated from a point inside of an object area. The second angle-distance graphs are generated for the areas missed in the first graph by extracting the positions with large gradient in the first angle-distance graph. The order of the graph increases according to the complexity of an object pattern. Size of the area inside of an object boundary is measured by integrating square of distance multiplied by angle for each area from the hierarchical angie-distance graphs.

Comparison of Femoral Anteversion Angle and Determination of Reliability Measured at Three Different Anatomical References of the Tibial Crest During the Trochanteric Prominence Angle Test

  • Lee, Ji-Hyun;Yoon, Tae-Lim;Choi, Sil-Ah;Cynn, Heon-Seock
    • Physical Therapy Korea
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    • 제19권4호
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    • pp.55-60
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    • 2012
  • The trochanteric prominence angle test (TPAT) has been used to measure the femoral anteversion angle between the tibial crest and the vertical line. However, the exact anatomical reference of the tibial crest has not yet been identified in the literature. Thus, the purposes of this research were twofold: first, to compare the femoral anteversion angle measured at three different anatomical references of the tibial crest (the proximal tibial crest, the proximal third of tibial crest, and the proximal half of tibial crest) and, second, to determine inter-and intra-rater reliabilities of the femoral anteversion angle measured at these three different anatomical references of the tibial crest during the TPAT. We recruited 14 healthy subjects, and a total of 28 legs were examined. The TPAT was measured using a digital inclinometer. A 1-way repeated-measure analysis of variance was used to compare the femoral anteversion angle measured at three different anatomical references of the tibial crest, and intraclass correlation coefficients (ICCs) were calculated to determine reliability. The femoral anteversion angle measured at the proximal tibial crest was significantly higher than that at the proximal third of the tibial crest and the proximal half of the tibial crest. The inter-and intra-rater reliabilities of femoral anteversion angle were measured at three anatomic references of the tibial crest were all found to be high during the TPAT (ICC=.9 0~.98). In conclusion, clinicians should recognize that the different degrees of the femoral anteversion angle could be measured when different anatomical references of the tibial crest were used, and that reliabilities were high when an exact anatomical reference of the tibial crest was used during the TPAT.

A Study on the Algorithm Development of End-point Position Tracking for Aerial Work Platform with Bend-linked Boom (굴절링크 붐을 갖는 장비의 끝점 좌표 추적 알고리즘 개발에 대한 연구)

  • Oh, Seok-Hyung;Hong, Yong
    • Journal of Power System Engineering
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    • 제20권3호
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    • pp.64-73
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    • 2016
  • In this research work, an algorithm development on tracking end-point of aerial work platform with jib profile and bend-linked boom was carried out to find the X, Y and Z direction value using coordinate transformation matrix. This matrix consists of device status value(length and angle) based on camera position axis, which are sent from device controller PLUS+1 by CAN protocol. These values are used to measure the distance and angle from the camera to the end-point. Using these distance and angle value, monitoring system controls FAN/TILT/ZOOM status of camera to get an adequate scene of workplace. This program was written in Java, C# and C for mobile device. These results provide the information to the aerial work device for secure operation.

Measurement of Refractive Index of Solid Medium by Critical Angle Method When Air Gap is Present

  • Lim, Hwan-Hong;Kwon, Moon-Soo;Choi, Hee-Joo;Kim, Byoung-Joo;Cha, Myoung-Sik
    • Journal of the Optical Society of Korea
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    • 제12권3호
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    • pp.210-214
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    • 2008
  • A critical angle method was used to measure the index of refraction of a solid medium when an air gap between the prism and the medium is present. The gap effect was analyzed both numerically and experimentally. Since the total internal reflection is severely disturbed by the large gap, determination of the critical angle and the resulting refractive index becomes ambiguous and inaccurate. By using an index matching fluid, we could determine the index of refraction with an uncertainty of ${\pm}2{\times}1^{-3}$ even when the gap is as large as 1 ${\mu}m$.

The Effcts of Temperature and Ni Addition on the Wetting Behaviour of Cu on W (텅스텐판상에서 구리액상의 습윤거동에 미치는 온도 및 니켈 첨가의 효과)

  • 이재성
    • Journal of the Korean institute of surface engineering
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    • 제16권2호
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    • pp.41-47
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    • 1983
  • An investigation has been performed on the effects of temperature and Ni addition on the wetting behaviour of Cu on W substrate in hydrogen atmosphere. An sessile drop method was used to measure a wetting angle. The concentration profiles of W, Cu and Ni elements in W/Cu - 5 Ni specimen were made by EPMA. With increasing temperature, the wetting angle of Cu droplet on W plate decreases and the time to reach an equilibrium wetting angle is shortened in hydrogen atmosphere. The addition of Ni improves appreciably the wettability of Cu on W. With increasing Ni content in Cu liquid droplet(0, 1, 3, 5%), the wetting angle is decreased from 21$^{\circ}$to 0$^{\circ}$.

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An Experimental Study on Flow Angle with Swirl in a Horizontal Circular Tube (수평 원통 관에서 선회를 동반한 유동각에 대한 실험적 연구)

  • Chang, Tae-Hyun
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • 제2권4호
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    • pp.82-87
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    • 2003
  • Flow angle with Swirl in a horizontal circular tube and a cylindrical annuli were experimentally studied for its visualization. This present investigation deals with flow angle, flow visualization studies and vortex core by using oil smoke and a hot wire anemometer for Re = 40,000 and 50000 at X/D = 41, 59 and 71 in a horizontal circular tube. In the swirl air flow, a vortex core was formed at high swirl intensity along the test tube. The flow angle and the vortex core depended on the swirl intensity along the test tube. The results of flow angles with swirl measured by flow visualization and hot wire reasonably agree with those of Sparrow One of the primary objectives of this research was to measure the flow angle with swirl in a cylindrical annuli along the test tube for different Reynolds numbers. The Reynolds number for these measurements ranged from 60,000 to 100,000 with L/D = a to 4.

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