• Title/Summary/Keyword: Center-point error

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Vision Inspection and Correction for DDI Protective Film Attachment

  • Kang, Jin-Su;Kim, Sung-Soo;Lee, Yong-Hwan;Kim, Young-Hyung
    • Journal of Advanced Information Technology and Convergence
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    • v.10 no.2
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    • pp.153-166
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    • 2020
  • DDI(Display Driver IC) are used to drive numerous pixels that make up display. For stable driving of DDI, it is necessary to attach a protective film to shield electromagnetic waves. When the protective film is attached, defects often occur if the film is inclined or the center point is not aligned. In order to minimize such defects, an algorithm for correcting the center point and the inclined angle using camera image information is required. This technology detects the corner coordinates of the protective film by image processing in order to correct the positional defects where the protective film is attached. Corner point coordinates are detected using an algorithm, and center point position finds and correction values are calculated using the detected coordinates. LUT (Lookup Table) is used to quickly find out whether the angle is inclined or not. These algorithms were described by Verilog HDL. The method using the existing software requires a memory to store the entire image after processing one image. Since the method proposed in this paper is a method of scanning by adding a line buffer in one scan, it is possible to scan even if only a part of the image is saved after processing one image. Compared to those written in software language, the execution time is shortened, the speed is very fast, and the error is relatively small.

Contouring Error of a Machine Tool at Inflection Points (변곡점에서 공작기계의 윤곽오차)

  • 안일혁;김성수;민경석;최우천;홍대희
    • Journal of the Korean Society for Precision Engineering
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    • v.20 no.11
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    • pp.166-170
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    • 2003
  • Contouring errors are important especially for high speed and precision machining. In this study, contouring errors along contours having inflection points are studied. When a table of a machine tool moves along a circular path, acceleration acts toward the center of the circle. Thus, at inflection points, acceleration as well as inertia force changes its direction abruptly. The effect of inertia force on the contouring error is investigated in this study. It is found that the contouring error at an inflection point is proportional to the acceleration. This result can be useful in determining contouring errors along general paths.

An Analysis of Human Factor and Error for Human Error of the Semiconductor Industry (반도체 산업에서의 인적오류에 대한 인적요인과 과오에 대한 분석)

  • Yun, Yong-Gu;Park, Beom
    • Proceedings of the Safety Management and Science Conference
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    • 2007.04a
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    • pp.113-123
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    • 2007
  • Through so that accident of semiconductor industry deduces unsafe factor of the person center on unsafe behaviour that incident history and questionnaire and I made starting point that extract very important factor. It served as a momentum that make up base that analyzes factors that happen based on factor that extract factor cause classification for the first factor, the second factor and the third factor and presents model of human error. Factor for whole defines factor component for human factor and to cause analysis 1 stage in human factor and step that wish to do access of problem and it do analysis cause of data of 1 step. Also, see significant difference that analyzes interrelation between leading persons about human mistake in semiconductor industry and connect interrelation of mistake by this. Continuously, dictionary road map to human error theoretical background to basis traditional accidental cause model and modern accident cause model and leading persons. I wish to present model and new model in semiconductor industry by backbone that leading persons of existing scholars who present model of existent human error deduce relation. Finally, I wish to deduce backbone of model of pre-suppression about accident leading person of the person center.

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The Error Analysis of measuring wind speed on Met Mast Shading Effect (기상탑 차폐 영향에 따른 측정 풍속의 오차 분석)

  • Ko, Suk-Whan;Jang, Moon-Seok;Lee, Yoon-Sub
    • Journal of the Korean Solar Energy Society
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    • v.31 no.3
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    • pp.1-7
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    • 2011
  • In the performance test for wind turbines of medium and large, The reference met-mast should be installed for measurement reference wind speed as IEC 61400-12-1 standards and design of booms for mounted an anemometer must be considered exactly. Boom-mounted cup anemometer are influenced by flow distortion of the mast and the boom. Therefore design of booms must be important so that flow distortion due to booms should be kept below 0.5%. But, in some cases at size of met-mast structure, the distance of boom from mast is longer then measurement of wind speed is impossible because of oscillation of boom-mounted anemometer. In this paper, We measured a wind speed at several point from mast and boom and we analyzed the error of wind speed at each point of measurement. Also, we will suggest a correction method using the data curve fitting about errors of wind speed between each point of mounted anemometer.

Development and Positioning Accuracy Assessment of Precise Point Positioning Algorithms Based on GLONASS Code-Pseudorange Measurements

  • Kim, Mi-So;Park, Kwan-Dong;Won, Jihye
    • Journal of Positioning, Navigation, and Timing
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    • v.3 no.4
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    • pp.155-161
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    • 2014
  • The purpose of this study is to develop precise point positioning (PPP) algorithms based on GLONASS code-pseudorange, verify their performance and present their utility. As the basic correction models of PPP, we applied Inter Frequency Bias (IFB), relativistic effect, satellite antenna phase center offset, and satellite orbit and satellite clock errors, ionospheric errors, and tropospheric errors that must be provided on a real-time basis. The satellite orbit and satellite clock errors provided by Information-Analytical Centre (IAC) are interpolated at each observation epoch by applying the Lagrange polynomial method and linear interpolation method. We applied Global Ionosphere Maps (GIM) provided by International GNSS Service (IGS) for ionospheric errors, and increased the positioning accuracy by applying the true value calculated with GIPSY for tropospheric errors. As a result of testing the developed GLONASS PPP algorithms for four days, the horizontal error was approximately 1.4 ~ 1.5 m and the vertical error was approximately 2.5 ~ 2.8 m, showing that the accuracy is similar to that of GPS PPP.

Comparison of Repositioning Error According to Eccentric and Concentric Contraction of the Ankle Dorsiflexor Muscle in the Ankle Joint

  • Jin-Hee Oh;Ju-Sang Kim;Chang-Jae Oh;Mi-Young Lee
    • The Journal of Korean Physical Therapy
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    • v.35 no.2
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    • pp.43-47
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    • 2023
  • Purpose: This study compared the movement control ability of the ankle joint according to the type of muscle contraction, namely, eccentric or concentric contractions. Methods: Thirty-four healthy adult subjects participated in this study. As a single group, before the experiment, the subjects were trained on achieving the required position of the ankle around the target point by manually controlling the ankle dorsiflexion by 10°. Concentric contraction starts at 0° and continues until the target point of 10° is reached. During an eccentric contraction, the ankle joint starts at 20° ankle dorsiflexion and continues till the target point is reached. Movements using eccentric contraction and concentric contraction were randomly performed 3 times each. Results: The results of comparing the difference in the movement control ability of each type of muscle contraction of ankle dorsiflexion showed that the measurement-remeasurement error was significant in eccentric contraction. Conclusion: In this study, we found a difference in the ability to control movement according to whether the contraction is eccentric or concentric. Therefore, we propose that the ability to control movement is affected by the type of muscle contraction.

Development of API module program for automatic tool compensation on machining center (머시닝센터의 자동공구보정을 위한 API모듈용 프로그램개발)

  • 정상화;신현성;김현욱
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.04a
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    • pp.100-105
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    • 2002
  • In general, manufacturing error originated in bad material, machine tool defection, tool defection, and tool breakage. When the manufacturing process is stable, the error is come from the tool wear. In common on-machine measurement, teaching probe and touch sensor are widely used, however in this thesis the automatic tool compensation system using electric touch point measuring system is developed and evaluated, and effective operating is proposed.

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NUMBER OF CYCLES IN EVOLUTIONARY OPERATION

  • Lim, Yong-B.;Park, Sung-H.
    • Journal of the Korean Statistical Society
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    • v.36 no.2
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    • pp.201-208
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    • 2007
  • Evolutionary operation (EVOP) proposed by Box (1957) is a method for continuous monitoring and improvement of a full-scale manufacturing process with the objective of moving the operating conditions toward the better ones. EVOP consists of systematically making small changes in the levels of the two or three process variables under consideration. Data are collected on the response variable at each point of two level factorial design with the center point and a cycle is said to have been completed. The cycles are replicated sequentially until the decision is made on whether further cycle of experiments is needed to conclude the significance of any of main effects or interaction effects or the curvature. In this paper, an improved flow chart of EVOP is proposed and how to determine the number of cycles is studied based on the size of type II error. In order to reject the alternative hypothesis of interests with more confidence and conclude that we believe in the null hypothesis of no effects, we propose a counter measure $p^*-value$ corresponding to the p-value. The relationship of $p^*-value$ to the probability of type II error ${\beta}$ under the alternative hypothesis of interests is analogous to that of p-value to the probability of type I error ${\alpha}$. Also the implementation of EVOP with a mixture experiment is discussed.

A Study on Superficial Dose of 6MV-FFF in HalcyonTM LINAC: Phantom Study (HalcyonTM 선형가속기 6MV-FFF 에너지의 표재 선량에 대한 고찰: Phantom Study)

  • Choi, Seong Hoon;Um, Ki Cheon;Yoo, Soon Mi;Park, Je Wan;Song, Heung Kwon;Yoon, In Ha
    • The Journal of Korean Society for Radiation Therapy
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    • v.32
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    • pp.31-39
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    • 2020
  • Purpose: The aims of this study were to compare the superficial dose with Optically Stimulated Luminescence Dosimeter(OSLD) measurement and Treatment Planning System(TPS) calculation for 6MV-Flattening Filter Free(FFF) energy using HalcyonTM and TrueBeamTM. Materials and methods: Phantom study was performed using the CT images of human phantom. In the treatment planning system, the Planning Target Volume(PTV) was contoured which is similar to Glottic cancer. Furthermore, Point(M), Point(R), and Point(L) were contoured at the iso-center of head and neck region and 5mm bolus was applied to the body contour. Each treatment plans using 6MV-FFF energy from HalcyonTM and TrueBeamTM with static Intensity Modulated Radiation Therapy(IMRT) and Volumetric Modulated Arc Therapy(VMAT) were established with eclipse. To reproduce the same position as the TPS, OSLDs were placed at the iso-center point and 5mm bolus was applied to compare the error rate after the dose delivery. Result: The results of the study using human phantom are as follows. In case of HalcyonTM, the mean absolute error rates of the point dose using the treatment planning system and the dose measured by OSLD were 1.7%±1.2% for VMAT and 4.0±2.8% for IMRT. Also TrueBeamTM was identified as 2.4±0.4% and 8.6±1.8% respectively for VMAT and IMRT. Conclusion: Through the results of this study, TrueBeamTM confirmed that the average error rate was 2.4 times higher for VMAT and 3.6 times higher for IMRT than HalcyonTM. Therefore, based on the results of this study, If we need a more accurate dose assessment for the superficial dose, It is expected that using HalcyonTM would be better than TrueBeamTM.

A Study on the Error Detection of Attached Cadastral Maps using GIS (GIS를 이용한 연속지적도 오류검증 방안)

  • Jung, Gu-Ha;Jun, Chul-Min;Koh, Jun-Hwan;Park, Yu-Ri
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2007.04a
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    • pp.243-248
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    • 2007
  • This study proposed a procedure to improve the error defection of attached cadastral maps using digital map data. In addition, this study also provided the direction for the accuracy improvement of attached cadastral maps by comparing analysis methods. - such as centroid, Lee Sallee shape index, and area index. The analysis is performed as follows. First, by using centroid measurement, the center point of cadastral maps and attached cadastral maps are compared. Secondly by using Lee Sallee shape measurement, the location accuracy of range area is investigated. Thirdly, by using area measurement, the range area within allowable error scope is verified. Based on analysis, the discrepancy between cadastral maps and the attacked cadastral maps are detected as follows; 98.2% from Lee Sallee shape index, 41.8% from centroid, 15.4% from area index in the whole error.

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