• Title/Summary/Keyword: Precise measurement

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A Methodology of Radiation Measurement of MOSFET Dosimeter (MOSFET 검출기의 방사선 측정 기법)

  • Lho, Young-Hwan;Lee, Sang-Yong;Kang, Phil-Hyun
    • Proceedings of the IEEK Conference
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    • 2009.05a
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    • pp.159-162
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    • 2009
  • The necessity of radiation dosimeter with precise measurement of radiation dose is increased and required in the field of spacecraft, radiotheraphy hospital, atomic plant facility, etc. where radiation exists. Until now, a low power commercial metal-oxide semiconductor(MOS) transistor has been tested as a gamma radiation dosimeter. The measurement error between the actual value and the measurement one can occur since the MOSFET(MOS field-effect transistor) dosimeter, which is now being used, has two gates with same width. The measurement value of dosimeter depends on the variation of threshold voltage, which can be affected by the environment such as temperature. In this paper, a radiation dosimeter having a pair of MOSFET is designed in the same silicon substrate, in which each of the MOSFETs is operable in a bias mode and a test mode. It can measure the radiation dose by the difference between the threshold voltages regardless of the variation of temperature.

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The OMM system for machined form and surface roughness measurement concerned with volumetric error (기계 체적오차가 고려된 가공형상-거칠기 측정 OMM 시스템)

  • 이상준;김선호;김옥현
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.05a
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    • pp.681-686
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    • 2000
  • Machining information such as machined form and surface roughness accuracy is an important factor for manufacturing precise parts. To this regard, OMM(On the Machine Measurement) has been issued for last several decades to alternate with CMM. In this research, measuring system consisting of a laser probe is developed for machined form and surface roughness measurement on the machine tool. The obtained machined form accuracy is compared with reference one defined in CAD model. The measured surface roughness data is compared with measured master surface beforehand. Furthermore, using the pre-defined volumetric error map approach compensates the geometric accuracy of the machine tool. The overall performance is compared with CMM, and verified the feasibility of the measurement system.

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The OMM System for Machined Form and Surface Roughness Measurement Concerned with Volumetric Error (기계 체적오차가 고려된 가공형상-거칠기 측정 OMM 시스템)

  • 이상준;김선호;김옥현
    • Journal of the Korean Society for Precision Engineering
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    • v.17 no.7
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    • pp.232-240
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    • 2000
  • Machining information such as machined form and surface roughness accuracy is an important factor for manufacturing precise parts. To this regard, OMM(On the Machine Measurement) has been issued for last several decades to alternate with CMM. In this research, measuring system consisting of a laser probe is developed for machined form and surface roughness measurement on the machine tool. The obtained machined form accuracy is compared with reference one defined in CAD model. The measured surface roughness data is compared with measured master surface beforehand. Furthermore, using the pre-defined volumetric error map approach compensates the geometric accuracy of the machine tool. The overall performance is compared with CMM, and verified the feasibility of the measurement system.

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Parallelism Measurement of Rolls by Using a Laser Interferometer (레이저 간섭계를 이용한 롤 평행도 측정 기술)

  • Choi, Jong Geun;Kim, Seongeun
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.23 no.6
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    • pp.642-646
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    • 2014
  • This research describes the measurement of roll parallelism by a laser interferometer. Parallelism among rolls is an important factor for improving the precision of printing devices. A laser interferometer, which is a device for the precise measurement of distance, can be utilized to measure parallelisms between rolls. To measure distance between two rolls by using a laser interferometer, the laser must not be severed during measurement. To achieve this condition, a linear motion guide was installed to each roll being measured, and continuous measurement of distance between two rolls was implemented by the simultaneous control of two mirrors installed on the guides. The method to measure parallelism between two rolls presented in this research can be utilized to improve printing precision by enhancing parallelism between rolls in printing devices.

Complete Simultaneous Analysis of Uranium Isotopes in NUSIMEP-7 Microparticles Using SEM-TIMS

  • Park, Jong-Ho;Jeong, Kahee
    • Mass Spectrometry Letters
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    • v.7 no.3
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    • pp.64-68
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    • 2016
  • Scanning electron microscopy combined with thermal ionization mass spectrometry (SEM-TIMS) was used to determine the precise isotope ratios of ultra-trace levels of uranium contained in individual microparticles. An advanced multiple ion counter system consisting of three secondary ion multipliers and two compact discrete dynodes was used for complete simultaneous ion detection. For verification purposes, using TIMS with complete simultaneous measurement, isotopes were analyzed in 5 pg of uranium of a certified reference material. A microprobe in the SEM was used to transfer individual particles from a NUSIMEP-7 sample to TIMS filaments, which were then subjected to SEM-TIMS and complete simultaneous measurement. The excellent agreement in the resulting uranium isotope ratios with the certified NUSIMEP-7 values shows the validity of SEM-TIMS with complete simultaneous measurement for the analysis of uranium isotopes in individual particles. Further experimental study required for investigation of simultaneous measurement using the advanced multiple ion counter system is presented.

In-line Critical Dimension Measurement System Development of LCD Pattern Proposed by Newly Developed Edge Detection Algorithm

  • Park, Sung-Hoon;Lee, Jeong-Ho;Pahk, Heui-Jae
    • Journal of the Optical Society of Korea
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    • v.17 no.5
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    • pp.392-398
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    • 2013
  • As the essential techniques for the CD (Critical Dimension) measurement of the LCD pattern, there are various modules such as an optics design, auto-focus [1-4], and precise edge detection. Since the operation of image enhancement to improve the CD measurement repeatability, a ring type of the reflected lighting optics is devised. It has a simpler structure than the transmission light optics, but it delivers the same output. The edge detection is the most essential function of the CD measurements. The CD measurement is a vital inspection for LCDs [5-6] and semiconductors [7-8] to improve the production yield rate, there are numbers of techniques to measure the CD. So in this study, a new subpixel algorithm is developed through facet modeling, which complements the previous sub-pixel edge detection algorithm. Currently this CD measurement system is being used in LCD manufacturing systems for repeatability of less than 30 nm.

Suggestion of assessment height for noise measurement according to the vertical radiation characteristics of railway noise (철도소음의 높이별 방사특성을 고려한 수음 평가 위치 제안)

  • Cho, Jun-Ho;Jang, Kang-Seok
    • Journal of Environmental Impact Assessment
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    • v.23 no.1
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    • pp.29-37
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    • 2014
  • Exact and precise noise measurement is the basis for the reduction measure R&D, impact assessment and prediction modeling for railway noise. In this study, research trend as well as national and international noise measurement standard are investigated. For the estimation of vertical radiation characteristics of railway noise, specially devised zig was used. From the noise measurement and analysis, exact noise height radiated from the railway was characterized. The obtained results will be used for the suggestion of the height of microphone position of railway noise measurements.

Network System Design for Measurement of Bridges (교량의 계측을 위한 네트워크 시스템 설계기법)

  • Cho, Hyo-Nam;Hong, Seung-Ho;Park, Kyung-Hoon;Kim, Wook-Heon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.3 no.2
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    • pp.221-232
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    • 1999
  • This study investigates the applicability and design scheme of fieldbus network in the measurement system used for precise and safe construction as well as efficient maintenance of bridges. In order to maximize the function and performance of bridge monitoring system, this study introduces the CAN(Controller Area Network), one of the fieldbus protocols, in the measurement system of bridges. This study presents the implementation method of CAN on the monitoring system of bridge, and also proposes a bandwidth allocation scheme for the design of network. The validity of the proposed CAN design method is verified through a simulation experiment. It is shown that the CAN can be readily applicable to the measurement system of bridges.

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A Statistical Program for Measurement Process Capability Analysis based on KS Q ISO 22514-7 Using R (R을 이용한 KS Q ISO 22514-7 측정 프로세스 능력 분석용 프로그램)

  • Lee, Seung-Hoon;Lim, Keun
    • Journal of Korean Society for Quality Management
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    • v.47 no.4
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    • pp.713-723
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    • 2019
  • Purpose: The purpose of this study is to develop a statistical program for capability analysis of measuring system and measurement process based upon KS Q ISO 22514-7. Methods: R is a powerful open source functional programming language that provides high level graphics and interfaces to other languages. Therefore, in this study, we will develop the statistical program using R language. Results: The R program developed in this study consists of the following five modules. ① Measuring system capability analysis with Type 1 study data: MSCA_Type1.R ② Measuring system capability analysis with Linearity study(Type 4 study) data: MSCA_Type4.R ③ Measurement process capability analysis with Type 1 study & Gage R&R study data: MPCA_T1GRR.R ④ Measurement process capability analysis with Type 4 study & Gage R&R study data: MPCA_T4GRR.R ⑤ Attribute measurement processes capability analysis : AttributeMP.R Conclusion: KS Q ISO 22514-7 evaluates measuring systems and measurement processes on the basis of the measurement uncertainty that was determined according to the GUM(KS Q ISO/IEC Guide 98-3). KS Q ISO 22514-7 offers precise procedures, however, computations are more intensive. The R program of this study will help to evaluate the measurement process.