• Title/Summary/Keyword: Precise measurement

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The Development of In-Plane Displacement Measurement System on Laser Speckle Interferometry (레이저 스페클 간섭법을 이용한 면내변위 측정시스템 개발)

  • Yoon H.S.;Kim K.S.;Park C.J.;Choi T.H.;Choi J.S.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.556-560
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    • 2005
  • The measurement method by Laser Speckle Interferometry which uses the interference law which will grow precedes and with it explains a resolution measurement ability and together the change of place arrowhead and general measurement, at real-time measurement sensitivity it has application boat song from candle precise measurement field it is increasing. But, currently the domestic application technique to sleeps and optical science military merit by optical science interferometer and directness it composes purchases to the level which it applies the expensive commercial business equipment the outside and in spite of the technical ripple effect is deficient even in many strong point. The hazard which complements like this problem point form technical development it leads from the research which it sees and an application degree and to sleep as the measurement equipment which tries to develop the small-sized optical science interference sensor and an interpretation program it raises it does.

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A Study on A Spacecraft Alignment Measurement System (위성체 얼라인먼트 측정 시스템에 관한 연구)

  • Park, Hong-Chul;Son, Young-Seon;Choi, Jong-Yeon;Yoon, Yong-Sik
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.32 no.7
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    • pp.98-104
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    • 2004
  • A spacecraft alignment measurement requires highly precise measurement accuracy which is less than ${\pm}0.5^{\circ}$. In general, such an alignment measurement has been performed by using three or more theodolites. However, it contains the latent accuracy error because of a position stability of spacecraft, etc. The new alignment measurement system which consists of a theodoilte, a rotating table and a digital inclinometer has been developed to possibly to possibly reduce the error. This paper describes the concept and methodology of methodology of measurement system. It was found that new measurement system can provide more accurate results than the conventional system.

A Study on the Improvement of Member Evaluation Method in the Condition Evaluation of Reinforced Concrete Buildings (철근콘크리트 건축물의 상태평가 중 부재평가방법 개선에 관한 연구)

  • Woo, Hye-Sung;Yi, Waon-Ho;Hwang, Kyung-Ran;Lee, Kwan-Hyeong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.3
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    • pp.85-91
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    • 2021
  • Type 1 and type 2 buildings must regularly conduct precise safety inspections and precise safety diagnosis for the safety and maintenance of facilities, and the safety grade of the building is determined according to the results of the implementation. In addition, the cycle of inspection and diagnosis is determined according to the safety grade of the building. In order to determine the safety grade of the building, a precise safety inspection conducts condition evaluation, and a precise safety diagnosis conducts condition evaluation and safety evaluation. Therefore, since the inspection and diagnosis cycle is determined according to the safety grade of the building, the condition evaluation and safety evaluation must be precise. However, in the case of member unit evaluation, which is the first step in evaluating the current condition, the evaluation grade is determined by using the representative value of the measurement result, and this may result in an error in the evaluation grade. To solve this problem, this study analyzed evaluation criteria for each evaluation item and presented evaluation criteria using inequalities to respond to measurement results and evaluation scores. In addition, we present a functional formula that can reflect performance scores for each evaluation item.

An Effective Real-Time Integer Ambiguity Resolution Method Using GPS Dual Frequency (GPS 이중주파수 측정치를 이용한 효율적인 실시간 미지정수 결정방법)

  • Son, Seok-Bo;Park, Chansik;Lee, Sang-Jeong
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.8
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    • pp.719-726
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    • 2000
  • A real-time precise positioning is possible with GPS carrier phase measurements with efficient integer ambiguity resolution techniques. It is known that more reliable and fast integer ambiguity resolution is possi-ble as the number of measurements increases. Most precise positioning systems use dual frequency measurements and the wide-lnae technique to resolve integer ambiguity. The wide-lane technique magnifies the measurement noise while it reduces the number of candidates to be examined. In this paper a new integer ambiguity resolution method using dual frequency is proposed The proposed method utilizes the relationship between the wide-lane single frequency and the narrow-lane ambiguities to resolve narrow-lane integer ambiguity after fixing the wide-lane integer ambiguity. Experiments with real data show that the proposed method gives fast and reliable results.

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A Study of the Opacity Correlation Factor between the Filtration Type and Light Extinction Type Diesel Smoke Meters (여지반사식과 광투과식 매연측정기의 매연도 상관계수에 관한 연구)

  • Kim, Young-Ju;Park, Kyoung-Seok
    • Transactions of the Korean Society of Automotive Engineers
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    • v.15 no.5
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    • pp.146-152
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    • 2007
  • Recently, The air pollution problems become hot issues as the production of the diesel automotive increases. The ministry of environment has enforced a precise inspection law to decrease the vehicle emission. In this circumstances, the smoke measurement is somewhat complicated by the use of the different type smoke meters. Although the paper filtration type opacimeter has been used for measuring smoke widely but currently the light extinction type is being used for precise inspection law. These two type opacimeters are different in their measuring principles on each other. So, for the time being the regulation standards can be confused by these two type opacimeters. In this article, The correlation factor between these two type opacimeters is studied by using engine dynamometer and vehicle test. The result of the dynamometer test shows the light extinction type is more sensitive than the filtration type by 1.47 times. But the relation factor by the vehicle test achieved 1.37 value, which is lower than that of the dynamometer test. In the future study the more precise research is needed to estimate the relation factor on vehicle test.

Design and Implementation for Motion Control System with Precise Driving Mechanism (정밀구동메커니즘 적용 모션제어시스템 설계 및 구현)

  • Lee, Sang-Kyung;Lee, Jun-Yeong;Choi, Yun-Seok;Park, Hong Bea
    • IEMEK Journal of Embedded Systems and Applications
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    • v.8 no.3
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    • pp.129-136
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    • 2013
  • In this paper, a motion control system based on 2-axis gimbal system is designed and implemented to drive a high speed and precision. The proposed system consists of the RS-422 interface, 2-axis gimbal platform, servo control unit integrated with a high speed DSP chip-set, servo amplifier unit, potentiometer sensor unit, and resolver sensor unit. The servo control unit using the high speed DSP firmware is designed to get a fast response without an overshoot with step input and a RMS error of low probability with ramp input. The servo amplifier unit using a voltage control is designed to resolve the zero-crossing distortion for precise motion. To verify the performance and stability of the implemented system, experiments are performed through a measurement of the time and frequency domain response in a laboratory environment by using a PXI(PCI eXtentions for Instrumentation).

The Comparison of the Accuracy upon the Manual Torque Generating Devices for the Implant (임플란트에 사용되는 수동 토크발생장치의 정확성 비교)

  • Kim, Dong-Hwan;Kim, Han-Su;Oh, Sang-Ho;Chung, Chae-Heon
    • Journal of Dental Rehabilitation and Applied Science
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    • v.23 no.3
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    • pp.227-237
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    • 2007
  • Various methods and torque generating devices are developed and employed to apply proper torque clinically. In this study, clinically used torque control devices are measured whether uniformed and precise torque are generated. Digital torque gauge are employed for measurement and torque driver, torque limiting device, torque indicating device are used for torque generating devices. ${\chi}^2$ distribution was formed and One-way ANOVA(Turkey test) was performed to measure torque values generated by each torque generating device. In the results, all companies have been shown slight errors and deviations. This indicates a difficulty of applying precise torque. Therefore, it would be recommended torque generating device should be checked whether uniformed and precise torque can be generated and an error should be corrected.

Application on the New Technology of Construction Structures Disaster Protection Management based on Spatial Information

  • Yeon, Sangho
    • International Journal of Internet, Broadcasting and Communication
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    • v.10 no.3
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    • pp.136-145
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    • 2018
  • The disaster monitoring technique by combination of the measurement method and the fine precision of the sensor collecting the satellite-based information that can determine the displacement space is available in a variety of diagnostic information and the GIS/GNSS by first sensor it is being requested from them. Be large and that the facility is operated nationally distributed torsional displacement of the terrain and facilities caused by such natural disasters progress of various environmental factors and the surroundings. To diagnose this spatial information, which contains the various sensors and instruments tracks the precise fine displacement of the main construction structures and the first reference in the Geospatial or more three-dimensional detailed available map and location information using the installed or the like bridges and tunnels produced to a USN/IoT change at any time, by combining the various positioning analysis of mm-class for the facility main area observed is required to constantly in the real time information of the USN/IoT environment sensor, and to utilize this as a precise fine positioning information by UAV/Drone to the precise fine displacement of the semi-permanent infrastructures. It managed to be efficient management by use of new technologies, analyzing the results presented to a method capable of real-time monitoring for a large structure or facility to construction disaster prevention.

Safety Assessment and Behavior Control System using Monitoring of Segmental PSC Box Girder Bridges during Construction (세그멘탈 PSC박스거더교량의 시공간 계측모니터링을 통한 확률적 구조안정성 평가 및 제어 시스템)

  • Shin, Jae-Chul;Cho, Hyo-Nam;Park, Kyung-Hoon;Bae, Yong-Il
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.5 no.3
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    • pp.191-201
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    • 2001
  • In spite of the increasing construction of segmental PSC box girder bridges, the techniques associated with real-time monitoring, construction control and safety assessment during construction have been less developed compared with the construction techniques. Thus, the development of an integrated system including real-time measurement and monitoring, control and safety assessment system during construction is necessary fur more safe and precise construction of the bridges. This study presents a prototype integrated monitoring system for preventing abnormal behavior and accidents under construction stages, that consist of behavior control system for precise construction, reliability-based safety assessment system, and structural analysis. Also, a prototype software system is developed on the basis of the proposed model. It is successfully applied to the Sea-Hae Grand Bridge built by FCM. The integrated system model and software system can be utilized for the safe and precise construction of segmental PSC bridges during construction.

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PRECISE OR81T DETERMINATION OF GPS-36 SATELLITE USING SATELLITE LASER RANGING (SLR을 이용한 GPS-36 위성의 정밀 궤도 결정)

  • 임형철;박관동;박필호;박종욱;조정호
    • Journal of Astronomy and Space Sciences
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    • v.19 no.4
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    • pp.385-394
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    • 2002
  • Satellite laser ranging is a technique for precisely measuring the range between a laser station and a satellite that is equipped with retro-reflectors. SLR technique was first used for Beacon-B satellite in 1964 with the ranging accuracy of meter level. Now the single shot have centimeter level accuracy and the normal point have mm level in ranging. In this study we developed the algorithm for precise orbit determination using SLR data and performed the orbit determination of GPS-36 satellite using the algorithm. RMS of the estimated orbit was 74cm when compared with IGS precise orbit. It is known that RMS of SLR measurement residual is below 55mm. But we were able to achieve 44mm RMS of residual throughout this study.