• Title/Summary/Keyword: Measurement data

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A Case Study on the Compatibility Analysis of Measurement Systems in Automobile Body Assembly

  • Lee, Myung-Duk;Lim, Ik-Sung;Sung, Chun-Ja
    • International Journal of Reliability and Applications
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    • v.9 no.1
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    • pp.7-15
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    • 2008
  • The dimensional measurement equipment, such as Coordinate Measurement Machine (CMM), Optical Coordinate Measurement Machine (OCMM), and Checking Fixture (CF), take multiple dimensional measurements for each part in an automobile industry. Measurements are also recorded under different measurement systems to see if the responses differ significantly over these systems. Each measurement system (CMM, OCMM, and CF) will be considered as different treatments. This set-up provides massive amounts of process data which are multivariate in nature. Therefore, the multivariate statistical analysis is required to analyze data that are dependent on each other. This research provides step by step methodology for the evaluation procedure of the compatibility of measurement systems and clarify a systematic analyzation among the different measurement system's compatibility followed by number of case studies for each methodologies provided.

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Development of the Aircraft CO2 Measurement Data Assimilation System to Improve the Estimation of Surface CO2 Fluxes Using an Inverse Modeling System (인버스 모델링을 이용한 지표면 이산화탄소 플럭스 추정 향상을 위한 항공기 관측 이산화탄소 자료동화 체계 개발)

  • Kim, Hyunjung;Kim, Hyun Mee;Cho, Minkwang;Park, Jun;Kim, Dae-Hui
    • Atmosphere
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    • v.28 no.2
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    • pp.113-121
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    • 2018
  • In order to monitor greenhouse gases including $CO_2$, various types of surface-, aircraft-, and satellite-based measurement projects have been conducted. These data help understand the variations of greenhouse gases and are used in atmospheric inverse modeling systems to simulate surface fluxes for greenhouse gases. CarbonTracker is a system for estimating surface $CO_2$ flux, using an atmospheric inverse modeling method, based on only surface observation data. Because of the insufficient surface observation data available for accurate estimation of the surface $CO_2$ flux, additional observations would be required. In this study, a system that assimilates aircraft $CO_2$ measurement data in CarbonTracker (CT2013B) is developed, and the estimated results from this data assimilation system are evaluated. The aircraft $CO_2$ measurement data used are obtained from the Comprehensive Observation Network for Trace gases by the Airliner (CONTRAIL) project. The developed system includes the preprocessor of the raw observation data, the observation operator, and the ensemble Kalman filter (EnKF) data assimilation process. After preprocessing the raw data, the modeled value corresponding spatially and temporally to each observation is calculated using the observation operator. These modeled values and observations are then averaged in space and time, and used in the EnKF data assimilation process. The modeled values are much closer to the observations and show smaller biases and root-mean-square errors, after the assimilation of the aircraft $CO_2$ measurement data. This system could also be used to assimilate other aircraft $CO_2$ measurement data in CarbonTracker.

Measures to Improve the Efficiency of the Portable Air Quality Measurement System

  • CHOI, Jong-Sun;CHO, Dong-Myung;KWON, Woo-Taeg
    • Journal of Wellbeing Management and Applied Psychology
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    • v.5 no.3
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    • pp.27-41
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    • 2022
  • Purpose: In this study, pollutants generated in industrial areas were measured using a Portable Air Quality Measurement System(PAQMS). This study intends to examine in detail improvement measures and operational capabilities to operate a more efficient PAQMS. Research design, data and methodology: This study compares and analyzes the measurement values of the PAQMS and the measurement values of the national air quality measurement network. It is intended to develop a PAQMS corresponding to the data of the national measurement network by minimizing the errors that occur during comparative measurement and analysis and supplementing and improving the problems that occur during the current equipment calibration. Results: A PAQMS is an essential equipment for faster and more accurate measurement and analysis of pollutants in case of untimely measurement and civil complaints due to Micro Climate(local weather and environmental influences). Currently, there are many atmospheric measurement equipment in Korea, but only equipment for each item is produced and sold. Currently, these devices on the market must satisfy various conditions such as stable power, temperature, and humidity to calculate accurate measurement values. Conclusions: Therefore, there is no equipment that satisfies the conditions for performing detailed measurement in the field where accurate measurement is required. In this study, these field work conditions and contents for stable measurement were mentioned in the text.

Consideration of Nano-Measurement Strategy (나노물질의 측정전략의 주요 쟁점)

  • Yoon, Chung-Sik
    • Journal of Environmental Health Sciences
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    • v.37 no.1
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    • pp.73-79
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    • 2011
  • The growing interest in nanotechnology has resulted in increasing concern and a number of published environmental and workplace measurements for assessing occupational exposure to engineered nanomaterials. However, the amount of previous exposure data remains limited. Furthermore the data available was collected with extensive variation in terms of exposure measurement strategy, which limits the ability to pool the data in the future. In response, this paper reviewed several pertinent issues related to exposure measurement strategy to suggest a harmonized measurement strategy which would make exposure data more useful in the future, e.g. correlation between exposure metrics, relationship between activity and exposure, task-based or shift-based assessment, background concentration, limitation of personal exposure monitoring and other determinants of exposure/modeling. An improved sampling strategy for nanomaterial exposure assessment should be considered in order to maximize the use of the data from various real time monitoring instruments.

Reliability Analysis Method for Repeated UT Measurement Data in Nuclear Power Plants (원전 배관의 반복 측정 데이터에 대한 신뢰도 분석 방법)

  • Yun, Hun;Hwang, Kyeong-Mo
    • Corrosion Science and Technology
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    • v.12 no.3
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    • pp.142-148
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    • 2013
  • Safety is a major concern in Nuclear Power Plants (NPPs). Piping systems in NPPs are very complex and composed of many components such as tees, elbows, expanders and straight pipes. The high pressure and high temperature water flows inside piping components. As high speed water flows inside piping, the pipe wall thinning occurs in various reasons such as FAC (Flow Accelerated Corrosion), LDIE (Liquid Droplet Impingement Erosion) and Flashing. To inspect the wall thinning phenomenon and protect the piping from damages, piping components are checked by UT measurement in every overhaul. During every overhaul, approximately 200~300 components (40,000~60,000 UT data) are examined in NPPs. There are some methods from EPRI for evaluating wear rate of components. However, only few studies have been conducted to find out the raw data reliability for the wear rate evaluation. Securing the reliable raw data is the key factor for a reasonable evaluation. This paper suggests the reliability analysis method for the repeatedly measured data for wear rate evaluation.

A Novel Transmission Line Characterization Based on Measurement Data Reconfirmation

  • Eo, Yungseon
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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    • v.27 no.3
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    • pp.17-27
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    • 2016
  • In the high-frequency characterizations of planar circuit components, measurement data may not be physical. It is mainly due to resonance effects concerned with discontinuities which are inevitable for a planar component characterization. In this paper, a novel accurate transmission line characterization method is presented that excludes the resonance effects based on measurement data reconfirmation. For the physically obvious data acquisition near the resonance frequencies of a transmission line, the additional lines with different line lengths are fabricated on the same substrate. The test transmission lines are characterized by using vector network analyzer (VNA) in 100 MHz to 26.5 GHz. It is shown that an accurate transmission line characterization can be achieved with the proposed measurement data reconfirmation technique.

Analysis of the urban flood pattern using rainfall data and measurement flood data (강우사상과 침수 실측자료를 이용한 도시침수 양상 관계분석)

  • Moon, Hye Jin;Cho, Jae Woong;Kang, Ho Seon;Lee, Han Seung;Hwang, Jeong Geun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2020.06a
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    • pp.95-95
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    • 2020
  • Urban flooding occurs in the form of internal-water inundation on roads and lowlands due to heavy rainfall. Unlike in the case of rivers, inundation in urban areas there is lacking in research on predicting and warning through measurement data. In order to analyze urban flood patterns and prevent damage, it is necessary to analyze flooding measurement data for various rainfalls. In this study, the pattern of urban flooding caused by rainfall was analyzed by utilizing the urban flooding measuring sensor, which is being test-run in the flood prone zone for urban flooding management. For analysis, 2019 rainfall data, surface water depth data, and water level data of a street inlet (storm water pipeline) were used. The analysis showed that the amount of rainfall that causes flooding in the target area was identified, and the timing of inundation varies depending on the rainfall pattern. The results of the analysis can be used as verification data for the urban inundation limit rainfall under development. In addition, by using rainfall intensity and rainfall patterns that affect the flooding, it can be used as data for establishing rainfall criteria of urban flooding and predicting that may occur in the future.

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Construction of Spatiotemporal Big Data Using Environmental Impact Assessment Information

  • Cho, Namwook;Kim, Yunjee;Lee, Moung-Jin
    • Korean Journal of Remote Sensing
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    • v.36 no.4
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    • pp.637-643
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    • 2020
  • In this study, the information from environmental impact statements was converted into spatial data because environmental data from development sites are collected during the environmental impact assessment (EIA) process. Spatiotemporal big data were built from environmental spatial data for each environmental medium for 2,235 development sites during 2007-2018, available from public data portals. Comparing air-quality monitoring stations, 33,863 measurement points were constructed, which is approximately 75 times more measurement points than that 452 in Air Korea's real-time measurement network. Here, spatiotemporal big data from 2,677,260 EIAs were constructed. In the future, such data might be used not only for EIAs but also for various spatial plans.

Study on Sound Field Analysis in Near-Field using Boundary Collocation Method; Decision of Optimum Points of Measurement for Line Array Sound Source with Weighting Value (경계배치법에 의한 근거리 음장 해석 기법 연구; 가중치를 갖는 선배열 음원의 최적 측정점 개수의 결정)

  • Kim, Won-Ho
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.1752-1761
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    • 2000
  • This paper describes the far-field estimation using the near-field measurement data. Measurement in far-field region gives us the acoustical characteristics of the source but in general measurement is made in near-field such as acoustic water tank or anechoic chamber, so far-field acoustical characteristics of the source should be predicted from near-field data. In this case, the number of measurement points in the near field which relates to the accuracy of the predicted field and the amount of data processing, should be optimized. Existing papers say that measurement points is proportional to kL and depends on geometry and directivity of the source. But they do not give us any definite criterion for the required number of measurement points. Boundary Collocation Method which is one of the far-field prediction methods, is analyzed based on Helmholtz integral equation and Green function and it has been found that the number of measurement points is optimized as 0.54kL which is about one half of the existing results.

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Anslysis of tool grip tasks using a glove-based hand posture measurement system

  • Yun, Myung Hwan;Freivalds, Andris;Lee, Myun W.
    • Journal of the Ergonomics Society of Korea
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    • v.14 no.1
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    • pp.69-81
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    • 1995
  • Few studies on the biomechanical analysis of hand postures and tool handling tasks exist because of the lack of appropriate measurement techniques for hand force. A measurement system for the finger forces and joint angles for the analysis of manual tool handling tasks was developed in this study. The measurement system consists of a force sensing glove made from twelve Force Sensitive Resistors and an angle-measuring glove (Cyberglove$^{TM}$, Virtual technologies) with eighteem joint angle sensors. A biomechanical model of the hand using the data from the measurement system was also developed. Systems of computerized procedures were implemented inte- grating the hand posture measurement system, biomechanical analysis system, and the task analysis system for manual tool handling tasks. The measurement system was useful in providing the hand force data needed for an existing task analysis system used in CTD risk evaluation. It is expected that the hand posture measurement developed in this study will provide an efficient and cost-effective solution to task analysis of manual tool handling tasks.s.

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