• Journal of Integrative Natural Science
• /
• v.14 no.3
• /
• pp.116-122
• /
• 2021

Properties and comparison of multivariate CUSUM and EWMA charts for monitoring Σ of multivariate normal N(${\underline{\mu}}$, Σ) process has considered. Comparison of the performances of the considered charts, the numerical values are obtained by simulation with 10,000 iteration in terms of ATS, ANSS and ANSW. We found that EWMA chart with small values of smoothing constant more effectively detects the process changes than with large smoothing constant. And we also found that CUSUM chart with small value of reference value is more effectively detecting the process change than with large reference value. If a process engineer has interest in detecting small amount of shift rather than large shift, he/she can be recommended to use small smoothing constant in EWMA chart and small reference value in CUSUM chart.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.17 no.2
• /
• pp.45-58
• /
• 2012

For the development of reference values and evaluation of water quality in various environmental conditions, we divided the coastal region around Korean peninsular into 5 distinctive ecological regions based on the influence of surface current, depth, tidal range, turbidity, and climate condition. We used national marine environment monitoring data collected by National Fisheries Research & Development Institute(NFRDI) from 2000-2009. For the reference values, we used maximum seasonal mean from 2000 to 2007 for DIN, DIP, and chlorophyll-a and minimum seasonal mean for secchi depth measured at stations without the influence of river runoff in each ecological regions. For the reference value of bottom dissolved oxygen saturation, we used minimum mean value of 90% calculated from minimal riverine influence stations of whole regions. We calculated enrichment score for each assessment criteria. The enrichment score of DIN, DIP, and Chlorophyll-a was 1 (=< reference value), 2 (< 110% of reference value), 3 (< 125% of reference value), 4 (< 150% of reference value), and 5 (> 150% of reference value). The enrichment score of DO saturation and Secchi depth was 1 (> reference value), 2 (> 90% of reference value), 3 (>75 % of reference value), 4 (> 50% of reference value), and 5 (< 50% of reference value). We calculated water quality index using weighted linear combination of five enrichment score for the comparison of whole regions. From the water quality index distribution calculated from all stations between 2000 and 2007 period, we classified into 5 grade based on the standard deviation calculated from total water quality index. We assigned grade very good(I), good(II), moderate(III), bad(IV), and very bad(V) when the water quality index was less than 23, minimum + 1 sd, +2 sd, +3 sd, and grater than minium+ 3 sd, respectively.

• Communications for Statistical Applications and Methods
• /
• v.6 no.1
• /
• pp.25-32
• /
• 1999

A single outlier can influence on the least squares estimators and can invalidate analysis based on these estimators. The Cook's statistic has been introduced to measure influence of individual data point on parameter estimation and the quantile of the F distribution is recommended as a reference value. but in practice subjective judgement is applied in the choice of appropriate quantile. A simple reference value is introduced in this paper which is developed by approximating conditional quantities of Cook's measure. The performance of the proposed criterion is evaluated through analysis of real data set.

• Analytical Science and Technology
• /
• v.15 no.6
• /
• pp.580-583
• /
• 2002

New approach is developed employing the overall uncertainty obtained from multiple measurements to evaluate the statistical significance for the difference between a given reference value and its measured value determined in a lab. The overall uncertainty is determined by separate combinations of the uncertainties arising from systematic and random effects. It is shown that the uncertainty term in regular t-test can be underestimated by n measurements.

• Journal of Society of Preventive Korean Medicine
• /
• v.23 no.2
• /
• pp.91-99
• /
• 2019

Objectives : The aim of this study was to examine the reference value of biomarker serum amyloid p (SAP) to diagnose blood stasis objectively. Methods : Pubmed-Medline, Cochrane library, EMBASE were searched using the key words 'SAP' and 'serum amyloid p' in June 2018. Original articles of human adults that published in English, studies that recruited from the clinical research settings or well defined population based cohorts were only included. Results : A total of 12 studies were selected to extract the reference value of SAP. It was between 8.5 ng/mL (0.0085 mg/L) to 57.5 mg/L. Although the disease varied, most of them showed elevated SAP levels in the disease group (1.1-1.5 times). Conclusions : This study is meaningful in that it summarizes the results of previous researches of SAP, which has the potential to be diagnostic index of blood stasis.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.60 no.9
• /
• pp.1651-1655
• /
• 2011

The reference impedances which is about 95% supply impedance value of residential consumers' supply impedances was published by IEC in 1980. The reference impedances are the standard values for use in determining the voltage disturbance characteristics of electrical equipment like the flicker. In IEC 60725, the reference impedances for premises having service current capacities less than 100A per phase and for service current capacities more than 100A per phase are recommended. And these reference impedances are targeted for the countries using 50Hz power frequency. Because of the frequency difference, the reactance values of the reference impedances will be increased in 60Hz power system like Korea, And also the reference impedances are different significantly each other according to declared voltage variation, power consumption and service wire length etc. Therefore It is needed to calculate the reference impedances suitable for domestic low-voltage power system. In this paper, the reference impedances for service current capacities less than 100A in 220/380V, 60Hz single-phase two wire and three-phase four wire low-voltage system are calculated, And the equations for service current capacities more than 100A to calculate the modulus value of maximum supply impedances are suggested base on IEC 60725 and the reference impedances for those are calculated on service current of 100A per phase.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2009.01a
• /
• pp.229-232
• /
• 2009

Shot change detection is an important technique for effective management of video data, so detection scheme requires adaptive detection techniques to be used actually in various video. In this paper, we propose an adaptive shot change detection algorithm using the mean of feature value on variable reference blocks. Our algorithm determines shot change detection by defining adaptive threshold values with the feature value extracted from video frames and comparing the feature value and the threshold value. We obtained better detection ratio than the conventional methods maximally by 15% in the experiment with the same test sequence. We also had good detection ratio for other several methods of feature extraction and could see real-time operation of shot change detection in the hardware platform with low performance was possible by implementing it in TVUS model of HOMECAST Company. Thus, our algorithm in the paper can be useful in PMP or other portable players.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.25 no.2
• /
• pp.25-28
• /
• 2021

Purpose CA 72-4 is a tumor marker that uses two monoclonal antibodies, CC49 and B72.3, to measure tumor-related glycoprotein(TAG72) in the serum. CA 72-4 is used to diagnose stomach, ovarian, and pancreatic cancers, and is known to perform high specificity for stomach cancer. The purpose of this study is to re-evaluate the reference value provided by the manufacturer through revalidation of the reference value in CA 72-4. Furthermore this study was conducted to provide useful help when making a clinical diagnosis at gastric cancer center. Materials and Methods We selected 271 patients who had been to health care center in national cancer center for the month of November 2020. The gender of the subjects was 140 males and 131 females, and the age group was from 30s to 60s. The reagent used in the study was a CA 72-4 IRMA KIT (ISOTOPES, Hungary) and the results were measured using a Dream Gamma-10 gamma counter (Shinjin medics, Korea). Results Statistical analysis of the results of this study used Hoffmann's method and Bayesian's method, which are primarily used in setting reference value. As a result of measuring CA 72-4 of 271 patients, the mean value was 4.54 U/mL and the median value was 3.30 U/mL. 24 people who deviated from 3SD were excluded from the measured value, the mean calculated after that was 3.53 U/mL, median was 3.00 U/mL and SD was 1.89. The reference value calculated based on this results was set to 7.31 U/mL. Conclusion The reference value provided by the manufacturer is less than 4 U/mL. It is slightly different from the value calculated in this study, 7.31 U/mL, so it seems necessary to reset the reference value according to the laboratory environment. Currently, we are receiving inquiries about the reference value from the center for gastric cancer at National Cancer Center. If additional research is carried out along with this study, it will be possible to set more accurate reference value.

• Korean Journal of Clinical Laboratory Science
• /
• v.45 no.3
• /
• pp.87-90
• /
• 2013

The activated partial thromboplastin time (APTT) is used primarily to evaluate coagulation abnormalities in the intrinsic pathway. The proper specimen is very important factor for precise results of blood coagulation analysis. The objective of this study was to get to the conclusion of whether to analyze again and to collect blood sample over again when APTT result shows below the reference value. We evaluated 126 samples showing a value below 20.0 sec at ATPT result, which consist of 48 males and 78 females candidates during night duty from March 2012 to December 2012. Average comparisons of APTT result between first and retested analysis among study subjects were significantly different in male samples. APTT results comparison of recollected subjects among clotted samples were also significantly different with both sexes (p<0.000). We suggest that we should carefully check the samples to get accurate results and collect samples again in case of only obtaining improper samples; even though the APTT result show below reference value.

• Journal of radiological science and technology
• /
• v.31 no.1
• /
• pp.41-47
• /
• 2008

In order to better understand the effects of absorbed radioiodine upon Korean reference adult male, a mathematical phantom representation was contrived based on composite data of the physiology of Korean reference adult male. Using this, S-values of radioiodine($^{131}I$) per each organ were calculated. The calculated S-values were compared to the existing data described in the TM-8381 report of ORNLcalculated on the basis of an ICRP-23 reference male. The results indicated that S-values were higher for the phantom based on Korean reference adult male. The results of this study illustrate that, while the bio-chemical constitution of each source and target organ of the torso are important, the relative location of the organs and characteristics of the radionuclides also exert important influences.