• Title/Summary/Keyword: Measurement instrument

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A Study on Mechanism Stated Number of Electro-Optical Distance Measuring Instrument (광파측거의의 기계정수에 관한 연구)

  • Lee, Y.H.;Mun, D.Y.
    • Journal of Korean Port Research
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    • v.5 no.2
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    • pp.77-84
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    • 1991
  • This paper is compared with fourier series and least square polynomial fit and interpolation to mechanism stated number in electro-optical distance measuring instrument. Systematic instrumental errors occurring in electro-optical systems include uncertainties in the position of the electrical center of the transmitter, uncertainties in the effective center of the reflectors. frequency drift and instrument nonlinearity. Microwave systems are affected by uncertainties in the electrical centers of the master and remote units and by a phenomenon called group swing or reflection. As the result of this study, mechanism stated number will be used as verification of electro0optical measuring instrument to distance measurement.

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A NEW METHOD - REAL TIME MEASUREMENT OF THE INITIAL DYNAMIC VOLUMETRIC SHRINKAGE OF COMPOSITE RESINS DURING POLYMERIZATION (복합레진의 초기 동적 체적 중합수축의 실시간 측정 -새로운 측정장치의 개발에 대한 소고-)

  • 이인복
    • Restorative Dentistry and Endodontics
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    • v.26 no.2
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    • pp.134-140
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    • 2001
  • The polymerization shrinkage of composite resins is an important drawback although the composites have many advantages-more esthetic and conservative than metallic restoratives etc. The purposes of this research were to develop a new measurement method and to manufacture an instrument that can measure the initial dynamic volumetric shrinkage of composite resins during polymerization. The instrument was basically an electromagnetic balance that constructed with a force transducer using position sensitive photo detector(PSPD) and a negative feedback servo amplifier of proportional-derivative(PD) controller. The volumetric change of composites during polymerization was detected continuously as buoyancy change in distilled water by means of Archimedes's principle. It was converted to continuous electrical voltage signal in real time. The signal was properly conditioned and filtered and then it was stored in computer by a data acquisition(DAQ) board. By using this electronic instrument. the dynamic patterns of the polymerization shrinkage of eight commercial(Z-100, DenFil, AeliteFil, Z-250, P-60, SureFil, Synergy compact, and Tetric ceram) composite resins were measured and compared. The results were as follows. 1. From this project of developing instrument, the ability has been achieved that can acquire and process data of electrical signal transformed from various physical phenomenon by using temperature, displacement. photo. and force transducer. As a consequence, the instrumentation and measurement system used to analyze the physical characteristics of various dental materials in dental research field can be designed, manufactured and implemented in lab. 2. This instrument has some advantages. It was insensible to temperature change and could measure true dynamic volumetric shrinkage in real time without complicated process. It showed accuracy and high precision results with small standard deviation. 3. The polymerization shrinkage of composites was significantly different between brands and ranged from 2.47% to 3.89%, The order of polymerization shrinkage was as follows, in order of increasing shrinkage, SureFil, P60, Z250, Z100, Synergy compact. DenFil, Tetric ceram, and AeliteFil. 4. The polymerization shrinkage rate per unit time, dVol%/dt, showed that the instrument can provide an indirect research method for polymerization reaction kinetics.

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A Study on the Field Application of particulate matter Measurement Instruments in Light Scattering Method (광산란법 미세먼지 계측기의 현장 적용성 평가에 관한 연구 )

  • Liu, Bao-lin;Lee, Chung-Won;Lim, Hyo-Jin;Tae, Sung-Ho
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.11a
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    • pp.201-202
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    • 2023
  • Now, there are many cases where materials are maintained at construction sites or standard construction prices are not in accordance with the applicable regulations, resulting in a lot of fine dust. Therefore, a particulate matter measurement system is applied not only to manage particulate matter at construction sites but also to reduce particulate matter .This study aims to evaluate the applicability of this particulate matter measurement system to the construction site through long-term measurement experiments using a light scattering method particulate matter measurement instrument at the construction site.

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Convergence review of self-care measurement instrument in diabetic nephropathy (당뇨병성 신증의 자가 관리 측정도구 고찰에 대한 융합연구)

  • Jun, Young-Hee;Song, Young-Shin
    • Journal of the Korea Convergence Society
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    • v.9 no.10
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    • pp.467-475
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    • 2018
  • The purpose of this study was to describe self-management related to diabetic nephropathy(DN) patients and analyze instrument for measurement of self-management. Literature search was conducted using computerized databases such as Pubmed, CINAHL, Embase, and Cochrane. The search term of this study were "Diabetes Mellitus", "Self-care", "Kidney Disease". A total of 8 articles were collected and 8 measurement instruments used in the study. But, included studies were assessing the self-management for DN using non-DN specific instruments. Thus, DN specific instrument for measuring the self-care should be developed in future study.

Audiometric Calibration of Aural Acoustic Immittance Instrument: A Review of Acoustic Immittance Instrument's Calibration

  • Kim, Jin-Dong
    • Biomedical Science Letters
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    • v.22 no.4
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    • pp.115-126
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    • 2016
  • Audiometric calibration is a prerequisite for securing the reliability of audiometric test results by checking the internal consistency of the relevant instrument. The purpose of this review is to help instrument operators understand the calibration procedure of aural acoustic immittance instrument which is frequently used for objective assessment. By referring to the latest international standards and the national standards relevant to the aural acoustic immittance instrument, the following parameters will be reviewed: 1) introduction of performance characteristics, 2) detailed procedure of the calibration method. According to the newest international and national standards [IEC 60645-5 (2004), ANSI S3.39-1987 (R2012)], the aural acoustic immittance instrument basically includes six components: 1) calibration cavity, 2) acoustic immittance analysis system, 3) probe assembly/unit and signal, 4) pneumatic air-pressure pump system, 5) acoustic reflex activator system and 6) tympanogram and acoustic reflex plotting system, each of these components should meet set standards. The result of behavioral hearing tests is influenced by various complex factors including the examinee's cooperation, background noise of the examination room, measurement method, skill level of the audiologist and calibration status, but the objective hearing tests is more influenced by the calibration status of the instrument than any other factors. The audiologist should take full responsibility for the reliability of the hearing test result, so he/she should carry out the calibration check and adjustments of aural acoustic immittance instrument periodically and maintain the instrument continuously by referring to the newest standards and the manufacturer's instruction manual.

A Study on the Development of Hourly Evaporation Recording Instrument for Class A Pan (대형증발계용 매시간 증발 기록계 개발에 관한 연구)

  • Bu-Yong Lee
    • Journal of Environmental Science International
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    • v.10 no.5
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    • pp.323-327
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    • 2001
  • A new method is developed to estimate the evaporation of water from a surface with high accuracy and resolution. The principle of new method is to detect a weight change of buoyant weight according to a change in water level of Class A Pan mesured by the use of a strain-gauge load cell. Field test of evaporation recording new instrument was carried out at Suwon for 10 days July 1999. It is possible in field observation to measure hourly evaporation amount by newly developed evaporation recording instrument in Class A Pan against strong solar radiation. Present study provide a possibility of domestic high accuracy instrument development below than 0.1mm water level measurement accuracy. If there is low humidity and high wind speed conditions which is possible to evaporate from water surface during night time. And it needs continuous study to understand between meteorological elements and latent heat effect at ground level by field observation study using high accuracy evaporation recording instrument.

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Temperature Measurement of Photovoltaic Modules Using Non-Contact Infrared System

  • Jovanovic, Ugljesa;Mancic, Dragan;Jovanovic, Igor;Petrusic, Zoran
    • Journal of Electrical Engineering and Technology
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    • v.12 no.2
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    • pp.904-910
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    • 2017
  • This paper presents temperature measurement of solar photovoltaic modules using the custom-made system composed of an infrared temperature sensor and a microcontroller. The obtained measurement results are processed, displayed and stored on a PC using the custom-made virtual instrument. The proposed system overcomes some of the problems related to the contact sensor application, and at the same time offers accurate readings and better flexibility. The proposed system is especially suitable for applications where the cost is a limiting factor in the choice of measuring system. The conducted analysis and the obtained results have shown an excellent accuracy of the proposed system in comparison to a high quality thermal imaging camera used as the reference instrument.

NDIR Multi-Gas Measurement System for Air Quality based on Wireless Sensor Network (무선센서네트워크 기반 공기질 측정을 위한 비분산적외선 복합가스측정시스템)

  • Paik, Seung Hyun;Lee, Jun Yeong;Jung, Sang Woo;Park, Hong Bae
    • IEMEK Journal of Embedded Systems and Applications
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    • v.11 no.5
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    • pp.299-304
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    • 2016
  • As public interest in air quality and environment problem is increasing, many researches are being carried out the gas measurement system. Especially, Non-dispersive infrared (NDIR) measurements using Beer-Lambert gas sensing principle with very high selectivity and long life time are noted for reliable method. It is possible to detect various gases such as carbon dioxide (CO2), carbon monoxide (CO), and nitrogen dioxide (NO2), but many researches are mostly concentrated on CO2 sensor. The multi-gas measuring instrument is high price and unwieldy, therefore it is not suitable for wide area required numerous instrument. So we study the NDIR multi-gas measurement system for air quality based on wireless sensor network, and experiment the realized measurement system.

Multi-function Wattmeter for Voltage, Current, and Power Measurement (정밀전압, 전류, 전력측정 다기능전력계)

  • Park, Yeong-Tae;Yu, Gwon-Sang;Jang, Seok-Myeong
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.51 no.10
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    • pp.568-572
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    • 2002
  • High precision voltages, currents, and electrical power measurements in wide range of frequency can be achieved by using the thermo-elements(thermal converters). This paper describes a development wattmeter, based on a thermal principle. The instrument has been performed measurement in the range of currents from 0 to 50 A, voltages up to 480 V, power factor 0.5 (lag, lead), 1 and frequencies from 60 Hz to 3 KHz. It is intended to be used by electric utilities, standard laboratories, testing laboratories, and applications where high measurement accuracy are attractive consideration.

Radiometric performance characterization for breadboard AMON-RA energy channel instrument for deep space albedo measurement

  • Jung, Kil-Jae;Ryu, Dong-Ok;Ahn, Ki-Beom;Oh, Eun-Song;Lee, Jae-Min;Kim, Yun-Jong;Yu, Jin-Hee;Yi, Hyun-Su;Ham, Sun-Jung;Yoon, Ji-Yeon;Yoon, Ho-Seop;Hong, Jin-Seok;Yang, Ho-Soon;Chon, Byong-Hyok;Hwang, Hae-Sook;Lee, Han-Shin;Kim, Sug-Whan;Lockwood, Mike
    • Bulletin of the Korean Space Science Society
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    • 2008.10a
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    • pp.35.2-35.2
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    • 2008
  • The Albedo MONitor and RAdiometer (AMON-RA) instrument system is designed to measure Earth global albedo anomaly over the wavelength range of 0.3um to 4um. The instrument consists of two interconnecting optical subsystems i.e. a visible channel and an energy channel. The energy channel instrument consists of a modified Winston cone, a couple of relay mirrors and a pyro-electric detector. First, we report the integration and alignment process, leading to the prototype bolometer instrument. We then discuss the radiometric performance characterization including laboratory measurement results and the future plan for further incorporation of the bolometer instrument into the prototype AMON-RA instrument.

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