• Title/Summary/Keyword: Measurement of association

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Development of Light Transmission Fluctuation for Particle Measurement in Solid-Gas Two Phase Flows

  • YANG, Bin;WANG, Zhan-ping;HE, Yuan;CAI, Xiao-Shu
    • Particle and aerosol research
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    • v.12 no.1
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    • pp.21-26
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    • 2016
  • In order to realize In-line and convenient measurement for solid-gas two phase flows, Light Transmission Fluctuation (LTF) based on the random variation of transmitted light intensity, light scattering theory and cross-correlation method was presented for online measurement of particle size, concentration and velocity. The statistical relationship among transmitted light intensity, particle size and particle number in measurement zone was described by Beer-Lambert Law. Accordingly, the particle size and concentration were determined from the fluctuation signal of transmitted light intensity. Simultaneously, the particle velocity was calculated by cross-correlation analysis of two neighboring light beams. By considering the influence of concentration variation in industrial applications, the improved algorithm based on spectral analysis of transmitted light intensity was proposed to improve measurement accuracy and stability. Therefore, the online measurement system based on LTF was developed and applied to measure pulverized coal in power station and raw material in cement plant. The particle size, concentration and velocity of powder were monitored in real-time. It can provide important references for optimal control, energy saving and emission reduction of energy-intensive industries.

A Study on the Accuracy of GNSS Height Measurement Using Public Control Points (공공기준점을 이용한 GNSS 높이측량 정밀도 분석 연구)

  • WON, Doo-Kyeon;CHOI, Yun-Soo;YOON, Ha-Su;LEE, Won-Jong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.24 no.2
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    • pp.78-90
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    • 2021
  • In order to construct a precision geoid, it has been diversified into land, sea, aviation, and satellite gravity measurement methods, and measurement technology has developed, making it possible to secure high-resolution, high-precision gravity data. The construction of precision geoids can be fast and conveniently decided through GNSS surveys without separate leveling, and since 2014, the National Geographic Information Institute has been developing a hybrid geoid model to improve the accuracy of height surveying based on GNSS. In this study, the results of the GNSS height measurement were compared and analyzed choosing existing public reference points to verify the GNSS height measurement of public surveys. Experiments are conducted with GNSS height measurements and analyzed precision for public reference points on coastal, border, and mountainous terrain presented as low-precision areas or expected-to-be low-precision in research reports. To verify the GNSS height measurement, the GNSS ellipsoid height of the surrounding integrated datum to be used as a base point for the GNSS height measurement at the public datum. Based on the checked integrated datum, the GNSS ellipsoid of the public datum was calculated, and the elevation was calculated using the KNGeoid18 model and compared with the results of the direct level measurement elevation. The analysis showed that the results of GNSS height measurement at public reference points in the coastal, border, and mountainous areas were satisfied with the accuracy of public level measurement in grades 3 and 4. Through this study, GNSS level measurement can be used more efficiently than existing direct level measurements depending on the height accuracy required by users, and KNGeoids 18 can also be used in various fields such as autonomous vehicles and unmanned aerial vehicles.

The Vibration measurement which occurs from the Elevator Cage of the Building (건축물(建築物) Elevator Cage의 진동(振動) 측정(測定))

  • Jeon, Euy-Sik;Cho, Byoung-Hoo
    • Journal of The Korean Digital Architecture Interior Association
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    • v.4 no.2
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    • pp.52-59
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    • 2004
  • The interest about noise and vibration which occurs in buildings is increasing by a living level elevation recently. Particularly, the vibration which occurs from the elevator cage of the building is possibility of damage to the users of the building continuously. So, the purpose of this study is to suggest of measuring results to the vibration that occurs from the elevator cage and propose the countermeasure of it.

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tudy on the Improvement of Reliability Assessment of Work Environment Measurement in Korea (작업환경측정 신뢰성평가제도 개선방안에 관한 연구)

  • Hwang, Gyuseok
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.29 no.1
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    • pp.50-56
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    • 2019
  • Objective: The aim of this study is to analyze the reliability assessment of work environment measurement, and to propose ways of improving the system. Methods: We have reviewed reports and articles on the reliability assessment written by KOSHA and academia in order to analyze problems related with the system and propose the alternatives. Results: There are three ways to improve the system of the reliability assessment. First of all, it is necessary to perform the reliability assessment by measuring the work environment when workers raise questions about the results so we can make workers trust these results of the reliability assessment. Secondly, we should inspect the workplace at first, not the work environment service provider, so we can increase the employer's recognition of his duty to practice the work environment measurement. Thirdly, the technical committee is needed for technical issues related with the work environment measurement. Conclusions: Above all, it is crucial to get the workers' interest and trust to improve the work environment measurement. The reliability assessment should support the meaning and value of the work environment measurement by practicing the reliability assessment whenever workers have a demand for this and operating the technical committee.

A Study on the Human Sensibility Measurement Technology of Texture Coordination (Texture Coordination의 감성공학적 연구)

  • 김미지자
    • Journal of the Korea Fashion and Costume Design Association
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    • v.3 no.1
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    • pp.47-55
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    • 2001
  • The Human Sensibility Measurement Technology, the engineering discipline that translate the imagination and good impression of human being into a physical factor for relevant product, is important to improve the quality of industrial products. This dissertation is aimed at measuring and evaluating the human sensibility for texture I presented the image scale in expectation of applying it to the production and choice of goods fitting into one's sensibility and to the coordination of goods which have similar images.

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A Study on Improvement through Analysis of Problem on Physical Activity Promotion System(PAPS) (학생건강체력시스템(PAPS)의 문제점 분석과 개선방안에 대한 연구)

  • Park, Hyoung-Kil
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.7
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    • pp.87-96
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    • 2021
  • The purpose of this study is to analyze the problems of the Physical Activity Promotion System(PAPS) implemented in elementary, middle, and high schools in Korea and to prepare improvement measures. The data of the study was obtained through in-depth interviews, related papers, and press releases. The research participants of this study were 5 incumbent physical education teachers who directly instruct and measure PAPS at school and 5 college students who directly experienced PAPS. The results of the study are as follows. First, the problems that occurred in the educational environment of PAPS were students' indifference, teachers' passive guidance, and decreased physical education hours replaced by PAPS measurement days. Second, the problems occurring in the measurement environment of PAPS were errors due to measurement equipment, deviations due to different measurement locations, and differences in grades according to measurement items. Third, the problems that occur in the measurement process of PAPS are the lack of measurement personnel, the expedient physical fitness measurement, and the non-standardized measurement method. In order to improve these problems and successfully apply PAPS, the following improvement measures should be attempted. Details on this are as follows. First, teachers should inspire students' interest and interest in PAPS. Second, it is necessary to secure the reliability of the measurement result value of PAPS. Third, it is necessary to systematically supplement the school education system for PAPS measurement.

A Theoretical Review for developing a Korean Type Marital Satisfaction Scale (한국형 결혼만족도 척도 개발을 위한 이론적 고찰)

  • 정현숙
    • Journal of the Korean Home Economics Association
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    • v.39 no.11
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    • pp.89-106
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    • 2001
  • The purpose of this study is to critically review the related issues of marital satisfaction scale in order to develop a Korean Type Marital Satisfaction Scale. Especially definitional ambiguity, unit of analysis theory of marital satisfaction and issues about measurement and cultural implication are reviewed. Also a section deals with suggestions that could be considered to develop Korean Type Marital Satisfaction Scale.

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Real-time High Resolution PM Monitoring in Seoul (서울지역 미세먼지의 실시간 고해상도 모니터링 방안)

  • Kang, Doo Soo;Bong, Choon Keun;Kim, Dae Seong
    • Particle and aerosol research
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    • v.15 no.2
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    • pp.67-78
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    • 2019
  • Since existing measurement sites are required to construct a high-cost PM measuring device and a measuring site of a large area, there is a limit to the construction of a high-resolution measurement network. Therefore, it is necessary to develop a low-cost, high-performance PM measuring device (as an alternative technology) that can increase the resolution of PM measurement, and it is necessary to establish a base to provide real-time PM information for whole people. Therefore, in this study, the alternative technique (light scattering method) for achieving the above object was examined, performance evaluation was carried out, and it was verified that the light scattering method was usable. Various PM measurement results were compared and analyzed to find PM monitoring points and resolutions we would like to propose.