• 제목/요약/키워드: position measurement

검색결과 2,303건 처리시간 0.035초

One Idea on a Three Dimensional Measuring System Using Light Intensity Modulation

  • Fujimoto Ikumatsu;Cho In-Ho;Pak Jeong-Hyeon;Pyoun Young-Sik
    • International Journal of Control, Automation, and Systems
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    • 제3권1호
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    • pp.130-136
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    • 2005
  • A new optical digitizing system for determining the position of a cursor in three dimensions(3D) and an experimental device for its measurement are presented. A semi-passive system using light intensity modulation, a technology that is well known in radar ranging, is employed in order to overcome precision limitations imposed by background light. This system consists of a charge-coupled device camera placed before a rotating mirror and a light-emitting diode whose intensity is modulated. Using a Fresnel pattern for light modulation, it is verified that a substantial improvement of the signal to noise ratio is realized for the background noise and that a resolution of less than a single pixel can be achieved. This opens the doorway to the realization of high precision 3D digitized measurement. We further propose that a 3D position measurement with a monocular optical system can be realized by a numerical experiment if a linear-period modulated waveform is adopted as the light-modulating one.

Pelvic AP X-ray 촬영 자세에 따른 골반변위 변화의 비교 연구 (A Comparative Study on the Changes of Pelvic Alignment between AP View of the Pelvis in Standing and Supine Position)

  • 이경무;박동수;김순중;정수현
    • 한방재활의학과학회지
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    • 제18권4호
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    • pp.161-169
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    • 2008
  • Objectives : This study was carried out to investigate the relationship of pelvic alignment between AP view of the pelvis in standing and supine position. Methods : Sixteen healthy peoples who get $51.59{\pm}4.14$ as average in SF-36 were evaluated by X-ray findings. After measuring innomiate measurement, off centering measurement, sacral ala measurement, illium shadow measurement, the area of obturator foramen, those were analyzed statistically. Results : It was not all to be corresponded to distort pelvic alignment of AP view of the pelvis in standing and in supine. Sometimes it was the opposite result. Conclusions : These results suggest that the diagnosis of pelvic alignment to go through on each position is brought about disagreement with each other.

커프크기와 측정부위에 따른 혈압측정치 비교 연구 (A Comparative Study of Blood Pressure According to Cuff Size and Measurement Site)

  • 송미령;김은경
    • 기본간호학회지
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    • 제16권1호
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    • pp.6-13
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    • 2009
  • Purpose: The purpose of this study was to identify differences in blood pressure according to cuff size and measurement sites of the participants. Method: The participants consisted of 50 women and 50 men whose upper arm circumference was $26\sim30cm$. They had no chronic illness and gave consent to participate. Blood pressure of the wrist was measured in the sitting position, the upper arm with a standard cuff, large and small cuffs were used for measurement in supine position and the thigh in prone position. The data were analyzed with paired t-test using SPSS 12.0 program. Result: The data for the upper arm showed a difference in systolic and diastolic blood pressure depending on the site of measurement. There was a significant difference between measurements with a standard cuff and measurements with large and small cuffs. The systolic blood pressure of the wrist and the thigh were significantly lower than that of the upper arm. Conclusion: These results suggest that the selection of an appropriate cuff is an essential element in ensuring accuracy when measuring blood pressure and differences in systolic blood pressure for the upper arm, wrist and thigh indicate the need to record the measuring site when measuring blood pressure.

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IMU-바로미터 기반의 수직변위 추정용 이단계 칼만/상보 필터 (A Two-step Kalman/Complementary Filter for Estimation of Vertical Position Using an IMU-Barometer System)

  • 이정근
    • 센서학회지
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    • 제25권3호
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    • pp.202-207
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    • 2016
  • Estimation of vertical position is critical in applications of sports science and fall detection and also controls of unmanned aerial vehicles and motor boats. Due to low accuracy of GPS(global positioning system) in the vertical direction, the integration of IMU(inertial measurement unit) with the GPS is not suitable for the vertical position estimation. This paper investigates an IMU-barometer integration for estimation of vertical position (as well as vertical velocity). In particular, a new two-step Kalman/complementary filter is proposed for accurate and efficient estimation using 6-axis IMU and barometer signals. The two-step filter is composed of (i) a Kalman filter that estimates vertical acceleration via tilt orientation of the sensor using the IMU signals and (ii) a complementary filter that estimates vertical position using the barometer signal and the vertical acceleration from the first step. The estimation performance was evaluated against a reference optical motion capture system. In the experimental results, the averaged estimation error of the proposed method was 19.7 cm while that of the raw barometer signal was 43.4 cm.

레이저 빔 궤적을 이용한 자동 랜딩 시스템 (Automatic Landing System using a Trajectory of Laser Beam)

  • 황진아;남기군;이장명
    • 제어로봇시스템학회논문지
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    • 제13권1호
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    • pp.39-45
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    • 2007
  • This paper proposes a method of container position measurement using automatic landing system that is estimated by a laser range finder. In the most of container position measurement methods, CCD cameras or laser scanners have been used to get the source data. However those sensors are not only weak for disturbances, for examples, the light, fog, and rain, but also the system cost is high. When the spreader arrives at the goal position, it is still swung by inertia or by wind effect. In this paper, the spreader swung data have been used to find the container position. The laser range finder is equipped in the front side of spreader. It can measure distance and relative position between spreader and container. This laser range finder can be rotated as desired by a motor. And a tilt sensor is equipped on the spreader to measure spreader sway. The relative position information between the spreader and a container using the laser range finder and tilt sensor is estimated through the geometrical analysis.

Reliability of Navicular Drop Measurements in Standing and Sitting Positions

  • Park, Ji-Won;Chang, Jong-Sung;Nam, Ki-Seok
    • The Journal of Korean Physical Therapy
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    • 제22권6호
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    • pp.29-33
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    • 2010
  • Purpose: This study was designed to investigate inter-rater and intra-rater reliability of navicular drop measurements by clinicians in sitting and standing positions. Methods: Fourteen subjects with pronated foot were recruited. Two physical therapists randomly assessed the same patients on different occasions but on the same day. Almost all patients were assessed on more than one day. The intra-rater and inter-rater reliability of navicular dropwas estimated by calculation of the intraclass correlation coefficient (ICC). Results: The intra-rater reliability of navicular drop measurements ranged from 0.93 to 0.87, the inter-rater reliability from 0.98 to 0.70 with the patient in standing and sitting positions. These results showed good reliability for calculated variables. Intra-rater and inter-rater reliability of navicular drop in standing position was higher than those of sitting position. Conclusion: Although inter-rater and intra-rater reliability of navicular drop in the sitting position was lower than in the standing position, measurement of navicular drop in the sitting position showed good reliability and was acceptable for patients who could not stand alone without assistance. We recommend that having the patient in the standing position is appropriate in navicular drop measurement.

Measurements of low dose rates of gamma-rays using position-sensitive plastic scintillation optical fiber detector

  • Song, Siwon;Kim, Jinhong;Park, Jae Hyung;Kim, Seunghyeon;Lim, Taeseob;Kim, Jin Ho;Kim, Sin;Lee, Bongsoo
    • Nuclear Engineering and Technology
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    • 제54권9호
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    • pp.3398-3402
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    • 2022
  • We fabricated a 15 m long position-sensitive plastic scintillation optical fiber (PSOF) detector consisting of a PSOF, two photomultiplier tubes, four fast amplifiers, and a digitizer. A single PSOF was used as a sensing part to estimate the gamma-ray source position, and 137Cs, an uncollimated solid-disk-type radioactive isotope, was used as a gamma-ray emitter. To improve the sensitivity, accuracy, and measurement time of a PSOF detector compared to those of previous studies, the performance of the amplifier was optimized, and the digital signal processing (DSP) was newly designed in this study. Moreover, we could measure very low dose rates of gamma-rays with high sensitivity and accuracy in a very short time using our proposed PSOF detector. The results of this study indicate that it is possible to accurately and quickly locate the position of a very low dose rate gamma-ray source in a wide range of contaminated areas using the proposed position-sensitive PSOF detector.

PSD센서를 사용한 로보트 추적 오차의 실시간 측정에 관한 연구 (An on-line measurement of robot tracking error via an optical PSD sensor)

  • 김완수;박용길;조형석;곽윤근
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국내학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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    • pp.433-437
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    • 1988
  • Direct measurement of the relative position between the end effector of robot and moving objects reduces difficulties caused by the joint encoder reading and transformation. For those purpose, the on-line sensing method using PSD sensor was developed in this paper. The sensor was calibrated on the precision table. Then, the relative position of a moving objects on the conveyor was measured while the robot was tracking the one.

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cds 광전소자(光電素子)를 이용한 인공태양(人工太陽) 일사강도(日射强度)의 동시측정(同時測定) (One-time measurement of irradiation intensity of Solar Simulator using cds photo-sensors)

  • 배강;조서현;이보호;오정무
    • 태양에너지
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    • 제5권2호
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    • pp.28-34
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    • 1985
  • There are two kinds of irradiation intensity deviation, depending on time and position, on illuminated plane when thermal performance of solar collector is tested by using solar simulator. In this study we measured only position deviation of irradiation intensity using 45-cds photosensors and data acqusition system and found the point of average value. By this result we can improve the accuracy of irradiation measurement in indoor test of solar collector.

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