• Title/Summary/Keyword: correction of analysis

Search Result 2,515, Processing Time 0.034 seconds

A Study on the Shape Correction of Stamped Parts by the Irradiation of Laser (레이저를 이용한 스탬핑 제품의 스프링백 형상교정에 관한 연구)

  • Shim, H.B.;Kim, D.W.
    • Transactions of Materials Processing
    • /
    • v.18 no.7
    • /
    • pp.519-530
    • /
    • 2009
  • The study is concerned with shape correction of stamped product using the laser irradiation. As a fundamental study, laser irradiation process has been analyzed through the thermo-mechanical FE analysis. For the purpose of validation, laser scanning experiment has been carried out also. Since the deformation mechanism involved in the laser scanning is extremely complicated due to the highly temperature dependent material properties, the determination of laser scanning pattern is not easy for the application of real stamped parts. A simplified method for the application of springback correction has been suggested with the thermo-mechanical FE analysis.

Establishment of Correction Equation for Filling Volumn according to Moisture Content (수분 함량별 부풀성 보정식 설정)

  • Chung Han-Joo;Kim Yong-Ok
    • Journal of the Korean Society of Tobacco Science
    • /
    • v.27 no.1 s.53
    • /
    • pp.94-99
    • /
    • 2005
  • To correct the difference of filling volumn for various cut tobacco and puffed stem according to moisture contents, correction equation was estamated by a simple regression analysis. The $R^2$(coefficient of determination) of correction equation was above 0.95. To verify the precision of correction equation, we predicted correction equation of other samples. The filling volumns by the difference of $1\%$ moisture content were $0.018\;~\;0.022cc/g$ (cut tobacco) and 0.060cc/g (puffed stem). The precision of correction equation for various cut tobacco was very high, but that of puffed stem was low due to quality deviation of row stem according to a season.

Physical Artifact Correction in Nuclear Medicine Imaging: Normalization and Attenuation Correction (핵의학 영상의 물리적 인공산물보정: 정규화보정 및 감쇠보정)

  • Kim, Jin-Su;Lee, Jae-Sung;Cheon, Gi-Jeong
    • Nuclear Medicine and Molecular Imaging
    • /
    • v.42 no.2
    • /
    • pp.112-117
    • /
    • 2008
  • Artifact corrections including normalization and attenuation correction were important for quantitative analysis in Nuclear Medicine Imaging. Normalization is the process of ensuring that all lines of response joining detectors in coincidence have the same effective sensitivity. Failure to account for variations in LOR sensitivity leads to bias and high-frequency artifacts in the reconstructed images. Attenuation correction is the process of the correction of attenuation phenomenon lies in the natural property that photons emitted by the radiopharmaceutical will interact with tissue and other materials as they pass through the body. In this paper, we will review the several approaches for normalization and attenuation correction strategies.

A Comparative Study of Blood Lead Measurement by Polarized Zeman Effect Correction AAS and D2 Correction AAS Method (편광 Zeeman 보정 및 D2 보정 방법에 의한 혈중연 측정치의 비교 연구)

  • Lee, Seok Ki;Ahn, Kyu Dong;Lee, Byung Kook
    • Journal of Korean Society of Occupational and Environmental Hygiene
    • /
    • v.5 no.1
    • /
    • pp.59-67
    • /
    • 1995
  • Blood lead assay by $D_2$ lamp background correction method of atomic absorption spectrophotometer(AAS) with wavelength of 283.3 nm is most popular in occupational health practice in Korea. On the other hand, $D_2$ lamp background correction method with wavelength of 217.0 nm is also often used in general chemical analysis for lead assay in general purpose. But both methods have some weakness of background correction which brought direct effect on the results of analysis. Recently blood lead assay with polarized Zeeman effect of AAS was introduced and is now preferred in many laboratory than $D_2$ correction method in blood lead analysis. But still AAS with $D_2$ lamp are widely used in the field of occupational health in Korea. This study compared blood lead assay data with $D_2$ correction methods(283.3 and 217.0 nm) and with that of polarized Zeeman effect correction method to evaluate the validity of 02 correction methods. The results obtained were as follows; 1. Taking the value of polarized Zeeman effect method as reference value of 1.00, the mean relative value of $D_2$ correction method with wavelength of 217.0 nm was 0.92 and that with wavelength of 283.3 nm was 0.90 respectively in the analysis of blood lead whose value were below $20.0{\mu}g/dl$(p<0.001). Both mean values were statistically smaller than polarized Zeeman effect correction method. But in the analysis of blood whose value were between 20.0 to $20.0{\mu}g/dl$, the mean relative value of $D_2$ correction method was 0.96 in both wavelength and did not differ from polarized Zeeman effect method(p<0.001). There was no difference of blood lead between $D_2$ correction method and polarized Zeeman effect method in the analysis of blood lead whose value were over $40.0{\mu}g/dl$. 2. The variations of background correction value in polarized Zeeman effect method were not changed by increase of blood lead, but those in $D_2$ correction methods were increased by the increase of blood lead. While then relative standard deviation(RSD) of data measured by Zeeman effect method were decreased by the increase of blood lead, those by $D_2$ methods were nol differed by the increase of blood lead.

  • PDF

Performance Analysis of GNSS Residual Error Bounding for QZSS CLAS

  • Yebin Lee;Cheolsoon Lim;Yunho Cha;Byungwoon Park;Sul Gee Park;Sang Hyun Park
    • Journal of Positioning, Navigation, and Timing
    • /
    • v.12 no.3
    • /
    • pp.215-228
    • /
    • 2023
  • The State Space Representation (SSR) method provides individual corrections for each Global Navigation Satellite System (GNSS) error components. This method can lead to less bandwidth for transmission and allows selective use of each correction. Precise Point Positioning (PPP) - Real-Time Kinematic (RTK) is one of the carrier-based precise positioning techniques using SSR correction. This technique enables high-precision positioning with a fast convergence time by providing atmospheric correction as well as satellite orbit and clock correction. Currently, the positioning service that supports PPP-RTK technology is the Quazi-Zenith Satellite System Centimeter Level Augmentation System (QZSS CLAS) in Japan. A system that provides correction for each GNSS error component, such as QZSS CLAS, requires monitoring of each error component to provide reliable correction and integrity information to the user. In this study, we conducted an analysis of the performance of residual error bounding for each error component. To assess this performance, we utilized the correction and quality indicators provided by QZSS CLAS. Performance analyses included the range domain, dispersive part, non-dispersive part, and satellite orbit/clock part. The residual root mean square (RMS) of CLAS correction for the range domain approximated 0.0369 m, and the residual RMS for both dispersive and non-dispersive components is around 0.0363 m. It has also been confirmed that the residual errors are properly bounded by the integrity parameters. However, the satellite orbit and clock part have a larger residual of about 0.6508 m, and it was confirmed that this residual was not bounded by the integrity parameters. Users who rely solely on satellite orbit and clock correction, particularly maritime users, thus should exercise caution when utilizing QZSS CLAS.

A Study on the Posture Maintenance Performance and Self-Efficacy in accordance with Posture Correction Program (자세교정프로그램에 따른 자세유지 수행과 자기효능감에 관한 연구)

  • Jang, Su-Gyeong
    • Journal of Korean Physical Therapy Science
    • /
    • v.7 no.2
    • /
    • pp.459-474
    • /
    • 2000
  • The purpose of this study is to identify the posture correction program as the development of the posture maintenance performance, and search for the more efficient posture correction program. The data analysis was processed by SPSS. The data was analysed with $x^2$-test, t-test, pearson product moment correlation, and stepwise regression analysis. The finding of this study is as follows: There are the homogeneity between two groups was verified on the know ledges CF=.697, df=2, P>.05), self-efficacy(F=.098, df=2, P>.05) about the posture. The developed posture correction program has proved to enhance the posture maintenance performance(knowledge t=1.60, P<.05 ; posture manintenance t=7.69, P<.01). The type of posture correction program showed some significant differences (t=5.62, P<.01) in the accuracy of movement way among the factors of the posture maintenance performance. The posture maintenance performance affected self-efficacy. Therefore, the major conclusion is as follows: The posture correction program was meaningfully effective on developing the posture maintenance, and with practice created accuracy much more on the posture maintenance movement way. The development of the posture maintenance performance affected the increase of self-efficacy about the posture. The self-efficacy has proved so powerful factor to influence on the posture maintenance performance development. So, the posture correction program should be done systematically and continually, and developing the posture maintenance performance should be done with practice. After the education, it should be reinforced through practice, midterm identification and reeducation and motivated with recognizing the accurate posture measurement. And it should be created the correction program to develop the high self-efficacy about the posture. It needs the strategy to educate the correct posture individually, and to spread to the society for healthy life style.

  • PDF

Calibration Technology for Precise Alignment of Large Flat Panel Displays (대형 평판 디스플레이의 정밀 정렬을 위한 캘리브레이션 기술)

  • Hong, Jun-Ho;Shin, Dongwon
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.21 no.3
    • /
    • pp.100-109
    • /
    • 2022
  • In this study, calibration technology that increases the alignment accuracy in large flexible flat panels was studied. For precise of calibration, a systematization of the calibration algorithm was established, and a calibration correction technique was studied to revise calibration errors. A coordinate systems of camera and UVW stage was established to get the global position of the mark, and equations for translational and rotational calibration were systematically derived based on geometrical analysis. Correction process for the calibration data was carried, and alignment experiments were performed sequentially in cases of the presence or absence of calibration-correction. Alignment results of both calibration correction and non-calibration correction showed accuracy performance less than 1㎛. On the other hand, the standard deviation in calibration-correction is smaller than non-calibration correction. Therefore, calibration correction showed improvement of the alignment repeatability.

Development of MATLAB GUI-based Software for Performance Analysis of RNSS Navigation Message and WAD-RNSS Correction (지역 위성항법시스템 항법메시지 및 광역 보정정보 성능 분석을 위한 MATLAB GUI 기반 소프트웨어 개발)

  • Jaeuk Park;Bu-Gyeom Kim;Changdon Kee;Donguk Kim
    • Journal of Advanced Navigation Technology
    • /
    • v.27 no.5
    • /
    • pp.510-518
    • /
    • 2023
  • This paper introduces a MATLAB graphical user interface (GUI) based software for performance analysis of navigation message and wide area differential correction of regional navigation satellite system (RNSS). This software was developed to analyze satellite orbit/clock-related performance of navigation message and wide area differential correction simulating RNSS for regions near Korea based on different distributions of monitor and reference stations. As a result of software operation, navigation message and wide area differential correction are given as output in MATLAB file format. From the analysis of output, it was confirmed that valid navigation message and wide area differential correction could be generated from the results about statistical feature of orbit and clock prediction errors, cm-level fitting errors for navigation message parameters, and 81.9% enhancement in range error for wide area differential correction.