• Title/Summary/Keyword: Real time measurement

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Development of the Soil Thermal Property and Temperature Measurement System for the Real-time Ampacity Estimation of Underground Power Cables (실시간 지중 전력케이블 용량 평가를 위한 토양 열 특성 및 온도 측정 시스템 개발)

  • Jeong, Seong-Hwan;Kim, Dae-Kyeong;Choi, Sang-Bong
    • Proceedings of the KIEE Conference
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    • 2002.07a
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    • pp.22-24
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    • 2002
  • This paper introduces the real-time soil thermal property analyzer and temperature measuring system which is combined with radio telecommunication technique. To measure the thermal parameters in real-time, the radio telecommunication technique are used the personal communication service (PCS) which is in the world-wide serviced commercially firstly by CDMA. The thermal property analyzer has an ability of measuring thermal resistivity, thermal diffusivity and thermal stability. To estimate the soil thermal properties, the curve fitting algorithm by means of the least square method are used. TCP/IP protocol and MTM are used to install the real-time soil thermal property and temperature measurement system at multiple locations along routes of the underground power cables and to reduce the cost of telecommunication.

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Real-time Compensation of Motion Errors Using Extended Twyman-Green Interferometry (확장 트와이만-그린 간섭계를 이용한 운동 오차의 실시간 보상)

  • 배은덕;오정석;김승우
    • Journal of the Korean Society for Precision Engineering
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    • v.20 no.10
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    • pp.112-119
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    • 2003
  • This paper presents an extended Twyman-Green interferometry that enables simultaneous and real-time measurement of 5-DOF motion errors of the translational moving stage. This method uses a null balancing technique in which two plane mirrors are used as target mirrors to generate an interferometric fringe utilizing the optical principles of Twyman-Green interferometry. Fringe is detected by 2D photodiode array for high-speed measurement. Errors are then independently suppressed by activation of piezoelectric actuators through real-time feedback control while the machine axis is moving. Experimental results demonstrate that a machine axis can be controlled with motion errors about 10 nm in linear displacement, 0.15 arcsec in angular displacement.

Real-time Risk Measurement of Business Process Using Decision Tree (의사결정나무를 이용한 비즈니스 프로세스의 실시간 위험 수준 측정)

  • Kang, Bok-Young;Cho, Nam-Wook;Kim, Hoon-Tae;Kang, Suk-Ho
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.31 no.4
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    • pp.49-58
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    • 2008
  • This paper proposes a methodology to measure the risk level in real-time for Business Activity Monitoring (BAM). A decision-tree methodology was employed to analyze the effect of process attributes on the result of the process execution. In the course of process execution, the level of risk is monitored in real-time, and an early warning can be issued depending on the change of the risk level. An algorithm for estimating the risk of ongoing processes in real-time was formulated. Comparison experiments were conducted to demonstrate the effectiveness of our method. The proposed method detects the risks of business processes more precisely and even earlier than existing approaches.

An Analysis on Treeing in XLPE by means of Image Processing (화상처리에 의한 XLPE의 트리잉 해석)

  • 이재봉;임장섭;정우성;김태성
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1994.11a
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    • pp.122-128
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    • 1994
  • Studies on treeing phenomena have depended on the visual measurement using optical microscope. In the visual measurement, it is difficult to analyze the treeing in real time because voltages are applied discontinuously and impossible to calculate the deterioated area by treeing. Only tree type and length are studied. In this paper, image processing is introduced and voltages are applied continuously. The tree length and area are calculated in real time from tree inception to breakdown. Growing characteristics about tree types are compared for the normalized breakdown time.

Basic Study on Monitoring System of Reservoir and Leeve Using Wireless Sensor Network (무선센서 네트워크 계측을 이용한 저수지 및 제방 계측시스템 구축에 관한 기초연구)

  • Yoo, Chanho;Kim, IkHoon;Lee, Seungjoo;Hwang, Jungsoon;Baek, Seungcheol
    • Journal of the Korean GEO-environmental Society
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    • v.19 no.1
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    • pp.25-30
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    • 2018
  • Conventional monitoring method is used for evaluation of the reservoir and levee at the highest height sections. In recent years, automated measurement technology has been developed, and the measurement results are transmitted, collected and stored in real time into management office. Despite the development of real time monitoring technology, the measurement results are not used directly or indirectly with facility management at real time. Recently, as wireless sensor network measurement technology has been developed based on internet of things, this study proposed a real - time measurement and evaluation system based on wireless sensor network technology in the reservoir structure. As a result of the seepage analysis for the application, it was confirmed that the volumetric water content changes together with the change of the seepage line inside the embankment body according to the change of the water level of the embankment. In other words, the applicability of the measurement system with the volumetric water ratio set as the sensor node was verified.

The Accuracy Analysis of RTK-GPS by Field Calibration in Plane Surveying (국지측량에서의 현장 Calibration에 의한 RTK-GPS 정확도 분석)

  • Park, Woon-Yong;Shin, Dong-Soo
    • Journal of Korean Society for Geospatial Information Science
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    • v.10 no.2 s.20
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    • pp.87-95
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    • 2002
  • Real-time Kinematic GPS enables high accuracy Positioning by real time. If ambiguity use an integer solution, can obtain accuracy of several 'mm', and can obtain accuracy of tens 'em' if use real solution. In this study, We accomplish surveying by existent traditional surveying techniques (Total Station), Static GPS techniques and RTK-GPS techniques by Field Calibration about uniformity measuring point and then compared and ana1yzed each techniques positioning accuracy etc.. Result that achieve by Static-GPS in Plane area, about all measuring points, expressed error fewer than 3cm. Result that achieve RTK-GPS Surveying by Field Calibration in Plane area, could know that RTK-GPS techniques by Field Calibration is available in Plane area because expressing errors fewer than all 6cm, except case that do not get fixed solution of ambiguity Field Calibration RTK-GPS could know economically than existent conventional type measurement and existent GPS's measurement techniques that efficiency is very high.

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Development of a Real-time 3D Intraoral Scanner Based on Fringe-Projection Technique (프린지 투영법을 이용한 실시간 3D 구강 내 스캐너의 개발)

  • Ullah, Furqan;Lee, Gunn-Soo;Park, Kang
    • Korean Journal of Computational Design and Engineering
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    • v.17 no.3
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    • pp.156-163
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    • 2012
  • Real-time three-dimensional shape measurement is becoming increasingly important in various fields, including medical sciences, high-technology industry, and microscale measurements. However, there are not so many 3D profile tools specially designed for specifically narrow space, for example, to scan the tooth shape of a human jaw. In this paper, a real-time 3D intraoral scanner is proposed for the measurement of tooth profile in the mouth cavity. The proposed system comprises a laser diode beam, a micro charge-coupled device, a graticule, a piezoelectric transducer, a set of optical lenses, and a polhemus device sensor. The phase-shifting technique is used along with an accurate calibration method for the measurement of the tooth profile. Experimental and theoretical inspection of the phase-to-coordinate relation is presented. In addition, a nonlinear system model is developed for collimating illumination that gives the more accurate mathematical representation of the system, thus improves the shape measurement accuracy. Experiment results are presented to verify the feasibility and performance of the developed system. The experimental results indicate that overall measurement error accuracy can be controlled within 0.4 mm with a variability of ${\pm}0.01$.

Real-Time Power Electronics Remote Wiring and Measurement Laboratory (PermLAB) Using 3-D Matrix Switching Algorithms

  • Asumadu, Johnson A.;Tanner, Ralph;Ogunley, Hakeem
    • Journal of Power Electronics
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    • v.10 no.6
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    • pp.611-620
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    • 2010
  • This paper presents a new architecture, called "Power Electronics Remote Wiring and Measurement Laboratory (PermLAB)", that translates a common gateway interface (CGI) string from a remote web user to a web server connected to a 3-dimension switching matrix board, can be used to switch on and off, and to control a cluster of instruments and components. PermLAB addresses real-time connection, switching, and data acquisition over the Internet instead of using simulated data. A software procedure uses a signature system to identify each instrument and component in a complex system. The Web-server application is developed in HTML, JavaScript and Java, and in C language for the CGI interface, which resides in a controller portion of LabVIEW. The LabVIEW software fully integrates the Web sever, LabVIEW data acquisition boards and controllers, and the 3-dimensional switching matrix board. The paper will analyze a half-wave rectifier (AC - DC converter) circuit connected over the Internet using the PermLAB. PermLAB allows students to obtain real data by real-time wiring of real circuits in the laboratory using a "virtual breadboard" on the Web. The software for the Web-based 3-dimensional system is flexible, portable, can be integrated into many laboratory applications or expanded, and easily accessible worldwide.

A Design of Real-time Automatic Focusing System for Digital Still Camera Using the Passive Sensor Error Minimization (수동 센서의 오차 최소화를 이용한 실시간 DSC 자동초점 시스템 설계)

  • Kim, Geun-Seop;Kim, Deok-Yeong;Kim, Seong-Hwan
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.51 no.5
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    • pp.203-211
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    • 2002
  • In this paper, the implementation of a new AF(Automatic Focusing) system for a digital still camera is introduced. The proposed system operates in real-time while adjusting focus after the measurement of distance to an object using a passive sensor, which is different from a typical method. In audition, measurement errors were minimized by using the data acquired empirically, and the optimal measuring time was obtained using EV(Exposure Value) which is calculated from CCD luminance signal. Moreover, this system adopted an auxiliary light source for focusing in absolute dark conditions, which is very hard for CCD image Processing. Since this is an open-loop system adjusting focus immediately after the distance measurement, it guarantees real-time operation. The performance of this new AF system was verified by comparing the focusing value curve obtained from AF experiment with the one from the measurement by MF(Manual-Focusing). In both case, edge detector was used for various objects and backgrounds.