• Title/Summary/Keyword: Position Accuracy

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A Study of Test Method for Position Reporting Accuracy of Airborne Camera (항공기 탑재용 카메라 위치출력오차 측정방안 연구)

  • Song, Dae-Buem;Yoon, Yong-Eun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.16 no.5
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    • pp.646-652
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    • 2013
  • PRA(Position Reporting Accuracy) for EO/IR(Electro-Optic/Infrared) airborne camera is an important factor in geo-pointing accuracy. Generally, rate table is used to measure PRA of gimbal actuated camera like EO/IR. However, it is not always possible to fix an EUT(Equipment for Under Test) to rate table due to capacity limit of the table on the size and weight of the object(EUT). Our EO/IR is too big and heavy to emplace on it. Therefore, we propose a new verification method of PRA for airborne camera and assess the validity of our proposition. In this method we use collimator, angle measuring instrument, 6 dof motion simulator, optical surface plate, leveling laser, inclinometer and poster(for alignment).

Identification of English labial consonants by Korean EFL learners (한국 EFL 학습자들의 영어 순자음의 인지)

  • Cho, Mi-Hui
    • Proceedings of the Korea Contents Association Conference
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    • 2006.11a
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    • pp.788-791
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    • 2006
  • The perception of English labial consonants was investigated via experiment where 40 Korean EFL learners identified nonwords with the target labial consonants [p, b, f, v] in 4 different prosodic locations. The results showed that there was a strong positional effect since the accuracy rates of the four target consonants differed by position. Specifically, the average accuracy rate for the target consonants was higher in the stressed intervocalic position and initial onset position than in the unstressed intervocalic position and final coda position. Further, the accuracy rate for [f] is was high in all prosodic locations except the unstressed intervocalic position. This is unexpected in markedness theory given that fricatives are assumed to be more difficult to learn than stops.

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ACCURACY OF FOUR ELASTOMERIC INTEROCCLUSAL RECORDING MATERIALS (수종 고무 교합인기 재료의 정확성에 관한 연구)

  • Bae, Jeong-Sik
    • The Journal of Korean Academy of Prosthodontics
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    • v.36 no.2
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    • pp.355-365
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    • 1998
  • The purpose of this study is to evaluate the accuracy of four elastomeric interocclusal recording materials and the weight change according to different storage period (24 hours, 48hours, 7days) and different conditions (dry, wet). The techniques for establishing the intercuspal position were centic occlusion interocclusal record with four elastomeric interocclusal recording materials (Ramitec, Stat-BR, Blu-Mousse, Regisil) (experimental groups) and location of the cast in a position of maximum in-terdigitation using tactile and visual method(control group). To evaluate the accuracy of four elastomeric interocclusal recording materials, the quality of contacts between the mounted casts was compared with the results of an occlusal examination of the same subjects. The results were as follows : 1. The most accurate method of articulating study casts at the intercuspal position was by hand articulation and no significant differences in accuracy were observerd among the experimental groups. 2. In case of interocclusal records storaged in dry sealed plastic box, no significant differences in accuracy were observed among the experimental groups. 3. In case of interocclusal records storaged in water, there was significant inaccuracy in Ramitec group. 4. The biggest weight change was observed in Ramitec group in all storage conditions

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Enhancement of Tracking Performance of Laser Tracking System for Measuring Position Accuracy of Robots

  • Hwang, Sung-Ho;Choi, Gyeong-Rak;Lee, Ho-Gil;Shon, Woong-Hee;Kim, Jin-Young
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.61.5-61
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    • 2001
  • The laser tracking system(LTS) presents the most promising technique for dynamic position measurement of industrial robots. This system combine the advantage of high accuracy with a contactless measurement technique. It is the measurement system of position in three dimensions using distance data obtained by laser interferometer and real time angle by tracking mirror assembly. After measuring the tracking error of the beam projected on the center of retroreflector in robot end effector, this system tracks the end effector continuously by adjusting tracking mirror angle to minimize this error ...

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High accuracy measurement of the position and orientation of SMD VR by Computer Vision (비젼을 이용한 SMD 부품의 위치 및 자세 계측)

  • 김병엽;송재용;한창수;박종현;이영민
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.04b
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    • pp.371-376
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    • 1995
  • Computer vision is applicated to measure the position and orientation of the SMD on 8mm Camcoder PCB and advanced image processing algorithms for high accuracy and real time processing are proposed. Illumination conditions are optimized for the best image formation and a set of LEDs is used as economic illuminator, which is regarded as a summation of many point sources. Conctete optical system is constructed and the performance of the proposed algorithm is verified by several experiments.

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The Impact on the accuracy of the basic CPR according to position and foot-board height of the basic CPR provider (심폐소생술 제공자의 발판 높이와 자세가 기본심폐소생술의 정확도에 미치는 영향)

  • Choi, Eun-Sook;Cho, Keun-Ja
    • The Korean Journal of Emergency Medical Services
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    • v.12 no.3
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    • pp.27-41
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    • 2008
  • Purpose : The purpose of this study was to supply basic data for the impact on the accuracy of basic CPR according to position and foot-board height of basic CPR provider. Methods : Study design was within - group design. Subjects were 25 EMT-P Students in K city. Interventions was basic CPR performed on a resuscitation manikin placed on a hospital bed, kneeling on the bed adjacent to the manikin. Data was analyzed using descriptive statistics and Friedman test. Results : In case of the basic CPR performed on a resuscitation manikin placed on a hospital bed, ventilation accuracy was the highest in less than 160 cm height, foot-board height : $34.2{\pm}1.48cm$, 91.4% and in 161-165 cm height, foot-board height : $26.0{\pm}2.14cm$, 88.4% and in 171-175 cm height, foot-board height : $23.0{\pm}1.41cm$, 91.3% and in the above 176 cm, kneeling on the bed, 95%. Chest compression accuracy was the highest in less than 160 cm height, foot-board height : $30.2{\pm}1.48cm$, 95.6% and in 161-165 cm height, kneeling on the bed, 97.6% and in 171-175 cm height, kneeling on the bed, 98.5% and in the above 176 cm, kneeling on the bed, 98.7% and foot-board height : $20.5{\pm}1.91cm$, 98.7%. Chest compression error was due to too weak : 2.0-35.4 times. There were ststistically significant differences in 191-195 cm group according to chest compression mean depths($x^2=10.824$, p = .013) and chest compression error (p = .040). Conclusion : In contrast to current guidelines, the position and foot-board height of basic CPR provider are very important to the accuracy of the basic CPR. Furthermore, we recommend that a using real time audiovisual feedaback system significantly improve the quality of chest compression and ventilation during resuscitation.

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Design and Manufacture of Laser Tracking System for Measuring Position Accuracy of Robots (로봇의 위치 정밀도 측정을 위한 LTS의 설계 및 제작)

  • Hwang, Sung-Ho;Lee, Ho-Gil;Park, Gyeong-Rak;Kim, Jin-Young
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.6
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    • pp.518-522
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    • 2001
  • The main problem of the calibration of robots is to measure the position and orientation of a robot end effector. The calibration methods can be used as tool to improve the accuracy of robots without change of the arm or control architecture or robots. But such calibration methods require accurate measurements. Dynamic measurement of position and orientation provides a solution for this problem and improves dynamic accuracy by dynamic calibration of robots. This paper describes the development of the laser tracking system capable of determining the static and dynamic performance of industrial robots. The structure and systems components are presented and basic experimental results are included to demonstrated the instrument performance. The system can be applied to the remote controlled mobile robots as well s the calibration of robots.

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Time Difference Characteristics of GPS Carrier Phase (GPS 반송파의 시각차분 특성)

  • You, Ho;Lee, Eun-Sung;Lee, Young-Jea;Jee, Gyu-In;Nam, Gi-Wook;Jun, Hyang-Sig
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.33 no.9
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    • pp.66-72
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    • 2005
  • As one of the methods that determine position using GPS carrier phase without the resolution of integer ambiguity, the characteristics of the time difference is analyzed in this paper. When determining position by the needed accuracy, the difference time gap becomes an important factor. It is said that accuracy is improved as the difference time gap is getting large, and finally the centimeter level accuracy is achieved after a certain difference time gap. In this paper, the characteristics of the time difference is analyzed using real data and a new parameter is proposed to predict the resulting position accuracy. The difference time gap when position error is converged to the centimeter level is estimated with the proposed parameter.

Study on the improvement of GNSS positioning accuracy on Korean railroad lines (위성항법시스템의 국내 철도적용시 측위정확성 개선 방안 연구)

  • Shin, Kyung-Ho;Shin, Duc-Ko;Song, Yong-Soo;Lee, Jae-Ho
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.109-116
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    • 2011
  • In this paper, we investigate the scheme to improve the position accuracy using GNSS(Global Navigation Satellite System). Then we configure the real-time DGPS environment with use of NTRIP currently being in service on the DGNSS central office of MLTM(Ministry of Land and Transportation). And we verify the improvement of position accuracy and the continuity of GPS correction data through the DGPS test in Chungbuk line and Joongang line.

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Development of Computer Program for Solving Astronomical Ship Position Based on Circle of Equal Altitude Equation and SVD-Least Square Algorithm

  • Nguyen, Van-Suong;Im, Namkyun
    • Journal of Navigation and Port Research
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    • v.38 no.2
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    • pp.89-96
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    • 2014
  • This paper presents an improvement for calculating method of astronomical ship position based on circle of equal altitude equation. In addition, to enhance the accuracy of ship position achieved from solving equation system, the authors used singular value decomposition (SVD) in least square method instead of normal decomposition. In maths, the SVD was proved more numerically stable than normal decomposition. Therefore, the solution of equation system will be more efficient and the result would be more accurate than previous methods. By proposal algorithm, a computer program have been developed to help the navigators in calculating directly ship position when the modern equipment has failure. Finally, some of experiments are carried out to verify effectiveness of proposed algorithm, the results show that the accuracy of ship position based on new method is better than the intercept method.