• Analytical Science and Technology
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• v.34 no.6
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• pp.267-274
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• 2021

Acid-base titration experiments were carried out using the same sample to obtain a direct comparison of analysis results between a new titrator and conventional Spectrator (SPT) titrators. This allowed the confirmation of an endpoint both by spectroscopic detection and by conventional titrators (automatic burette (ABT) and autotitrator (ATT)). Statistical analysis was performed on the measured values (endpoints) obtained using different titrators, to assess their differences by comparison of straightness, equivalence, ANOVA, F-test, and t-test results. The coefficients of determination, confirmed by straightness, were all >0.999. Thus, the null hypothesis that there was no statistical difference could not be rejected. The Bland-Altman analysis method was used to confirm agreement with the new experimental method. No discrepancy was found in the measured values obtained using different titrators used in this study.

• International journal of advanced smart convergence
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• v.12 no.1
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• pp.18-30
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• 2023

We compared empirically the forecast accuracies of the LSTM model, and the ARIMA model. ARIMA model used auto.arima function. Data used in the model is 100 days. We compared with the forecast results for 50 days. We collected the stock closing prices of the top 4 companies by market capitalization in Korea such as "Samsung Electronics", and "LG Energy", "SK Hynix", "Samsung Bio". The collection period is from June 17, 2022, to January 20, 2023. The paired t-test is used to compare the accuracy of forecasts by the two methods because conditions are same. The null hypothesis that the accuracy of the two methods for the four stock closing prices were the same were rejected at the significance level of 5%. Graphs and boxplots confirmed the results of the hypothesis tests. The accuracies of ARIMA are higher than those of LSTM for four cases. For closing stock price of Samsung Electronics, the mean difference of error between ARIMA and LSTM is -370.11, which is 0.618% of the average of the closing stock price. For closing stock price of LG Energy, the mean difference is -4143.298 which is 0.809% of the average of the closing stock price. For closing stock price of SK Hynix, the mean difference is -830.7269 which is 1.00% of the average of the closing stock price. For closing stock price of Samsung Bio, the mean difference is -4143.298 which is 0.809% of the average of the closing stock price. The auto.arima function was used to find the ARIMA model, but other methods are worth considering in future studies. And more efforts are needed to find parameters that provide an optimal model in LSTM.

• Tuberculosis and Respiratory Diseases
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• v.65 no.6
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• pp.476-486
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• 2008

Background: TRAIL (TNF-related apoptosis inducing ligand) is a newly identified member of the TNF gene family which appears to have tumor-selective cytotoxicity due to the distinct decoy receptor system. TRAIL has direct access to caspase machinery and induces apoptosis regardless of p53 phenotype. Therefore, TRAIL has a therapeutic potential in lung cancer which frequently harbors p53 mutation in more than 50% of cases. However, it was shown that TRAIL also could activates $NF-{\kappa}B$ in some cell lines which might inhibit TRAIL-induced apoptosis. This study was designed to investigate whether TRAIL can activate $NF-{\kappa}B$ in lung cancer cell lines relatively resistant to TRAIL-induced apoptosis and inhibition of $NF-{\kappa}B$ activation using proteasome inhibitor MG132 which blocks $I{\kappa}B{\alpha}$ degradation can sensitize lung cancer cells to TRAIL-induced apoptosis. Methods: A549 (wt p53) and NCI-H1299 (null p53) lung cancer cells were used and cell viability test was done by MTT assay. Apoptosis was confirmed with Annexin V assay followed by FACS analysis. To study $NF-{\kappa}B$-dependent transcriptional activation, a luciferase reporter gene assay was used after making A549 and NCI-H1299 cells stably transfected with IgG ${\kappa}-NF-{\kappa}B$ luciferase construct. To investigate DNA binding of $NF-{\kappa}B$ activated by TRAIL, electromobility shift assay was used and supershift assay was done using anti-p65 antibody. Western blot was done for the study of $I{\kappa}B{\alpha}$ degradation. Results: A549 and NCI-H1299 cells were relatively resistant to TRAIL-induced apoptosis showing only 20~30% cell death even at the concentration 100 ng/ml, but MG132 ($3{\mu}M$) pre-treatment 1 hour prior to TRAIL addition greatly increased cell death more than 80%. Luciferase assay showed TRAIL-induced $NF-{\kappa}B$ transcriptional activity in both cell lines. Electromobility shift assay demonstrated DNA binding complex of $NF-{\kappa}B$ activated by TRAIL and supershift with p65 antibody. $I{\kappa}B{\alpha}$ degradation was proven by western blot. MG132 completely blocked both TRAIL-induced $NF-{\kappa}B$ dependent luciferase activity and DNA binding of $NF-{\kappa}B$. Conclusion: This results suggest that inhibition of $NF-{\kappa}B$ can be a potentially useful strategy to enhance TRAIL-induced tumor cell killing in lung cancer.

• Environmental and Resource Economics Review
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• v.23 no.2
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• pp.187-224
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• 2014

We present key issues to consider in estimating damages from price-fixing cases and then apply the procedure addressing those issues to a transportation fuel market. Among the five methods of overcharge calculation, the regression analysis incorporating the yardstick method is the best. If the price equation relates the domestic price to the foreign price and the exchange rate as in the transportation fuel market, the functional form satisfying both logical consistency and modeling flexibility is the log-log functional form. If the data under analysis is of time series in nature, then the ARDL model should be the base model for each market and the regression analysis incorporating the yardstick method combines these ARDL equations to account for inter-market correlation and arrange constant terms and collusion-period dummies across component equations appropriately so as to identify the overcharge parameter. We propose a two-step test for the benchmarked market: (a) conduct market-by-market Spearman or Kendall test for randomness of the individual market price series first and (b) then conduct across-market Friedman test for homogeneity of the market price series. Statistical significance is the minimal requirement to establish the alleged proposition in the world of uncertainty. Between the sensitivity analysis and the model selection process for the best fitting model, the latter is far more important in the economic analysis of damage in price-fixing litigation. We applied our framework to a transportation fuel market and could not reject the null hypothesis of no overcharge.

• Journal of Korea Water Resources Association
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• v.39 no.12 s.173
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• pp.997-1012
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• 2006

We have presented a nonparametric stochastic approach for the SOI(Southern Oscillation Index) series that used nonlinear methodology called Nonlinear AutoRegressive(NAR) based on conditional kernel density function and CAFPE(Corrected Asymptotic Final Prediction Error) lag selection. The fitted linear AR model represents heteroscedasticity, and besides, a BDS(Brock - Dechert - Sheinkman) statistics is rejected. Hence, we applied NAR model to the SOI series. We can identify the lags 1, 2 and 4 are appropriate one, and estimated conditional mean function. There is no autocorrelation of residuals in the Portmanteau Test. However, the null hypothesis of normality and no heteroscedasticity is rejected in the Jarque-Bera Test and ARCH-LM Test, respectively. Moreover, the lag selection for conditional standard deviation function with CAFPE provides lags 3, 8 and 9. As the results of conditional standard deviation analysis, all I.I.D assumptions of the residuals are accepted. Particularly, the BDS statistics is accepted at the 95% and 99% significance level. Finally, we split the SOI set into a sample for estimating themodel and a sample for out-of-sample prediction, that is, we conduct the one-step ahead forecasts for the last 97 values (15%). The NAR model shows a MSEP of 0.5464 that is 7% lower than those of the linear model. Hence, the relevance of the NAR model may be proved in these results, and the nonparametric NAR model is encouraging rather than a linear one to reflect the nonlinearity of SOI series.

• Journal of Korean Society for Geospatial Information Science
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• v.22 no.2
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• pp.33-40
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• 2014

At present, Cadastral map of 2 dimensional is in the stream of changing it to 3 dimensional type supported by GPS and laser techniques. In addition, this steam can be explained at the same time with improvement of equipment of storing much information, support of equipment for imaginative 3D spatial information, and support of equipment of expressing land in 3D Cadastral. This study suggest to apply airborne lidar survey technique on cadastral map to acquire comparably and quickly detailed height of ground. For doing this, this study checked out credibility regarding accuracy of airborne lider survey. After choosing research area, this study has done the airborne lidar survey and acquire the result after surveying Cadastral Comparison Point to check out the accuracy of acquired results. In addition, this study check out the result of Cadastral Comparison Point and airborne lidar survey applied by paired sample t-test based on actual results. The result is that test statistics is 0.322 which is 5 % similar level and null hypothesis cannot be rejected, so this study found out that result of both survey ways are the same. Therefore, the result of airborne lidar survey can be utilized to build up 3D Cadastral information hereafter.

• Journal of The Korean Astronomical Society
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• v.51 no.4
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• pp.89-110
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• 2018

Active Galactic Nucleus (AGN) variability can be used to study the physics of the region in the vicinity of the central black hole. In this paper, we investigated intra-night optical variability of AGN in the COSMOS field in order to understand the AGN instability at the smallest scale. Observations were performed using the KMTNet on three separate nights for 2.5 to 5 hours at a cadence of 20 to 30 min. We find that the observation enables the detection of short-term variability as small as ~ 0.02 and 0.1 mag for R ~ 18 and 20 mag sources, respectively. Using four selection methods (X-rays, mid-infrared, radio, and matching with SDSS quasars), 394 AGN are detected in the $4deg^2$ field of view. After differential photometry and ${\chi}^2$-test, we classify intra-night variable AGN. The fraction of variable AGN (0-8%) is statistically consistent with a null result. Eight out of 394 AGN are found to be intra-night variable in two filters or two nights with a variability level of 0.1 mag, suggesting that they are strong candidates for intra-night variable AGN. Still they represent a small population (2%). There is no sub-category of AGN that shows a statistically significant intra-night variability.

• Journal of Biomedical Engineering Research
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• v.3 no.1
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• pp.23-30
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• 1982

The regimen of physical activity of the patient with coronary artery disease requires that he should not overshoot the prescribed heart rate based on his age, health and fuctional status of the heart during his exercise. The step input of work load, however, involves a great danger of overshooting. The purpose of this study was to desigil a system that makes it passible for a subject to check the overshooting. This system shows on tile H.R-meter, the amplified and filtered heart-rate signal of the subject received by the photosensor on his earlobe, puts it in the lead coinpensational circuit where it is conpared with the reference input signal(=the presfribed heart rate). The output of the lead compensational circuit works the aull meter. By means of this null meter, the subject knows whether he is overshooting the prescribed heart rate or not. He can continue the natl meter needle at the'Zero'position through the control of the speed of pedaling of the bicycle ergometer, An experimental test, made on eight men and four women in healthy condition, showed that 91. 7% of them vlaintained the stable heart rate and that the overshooting of the desired heart rate did not exceed $\pm$2BPM. According to the result of this experiment, since the heart rate feedback controller makes it possible for the subject to take the prescribed exercise based not on the work load but on the heart rate which incidentally is inexpensive, it can be made use of as the instrument for the regimen of pflysical activity by the patient with coronary artery disease.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.4
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• pp.194-202
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• 2019

Reliability analysis of the components frequently starts with the data that manufacturer provides. If enough failure data are collected from the field operations, the reliability should be recomputed and updated on the basis of the field failure data. However, when the failure time record for a component contains only a few observations, all statistical methodologies are limited. In this case, where the failure records for multiple number of identical components are available, a valid alternative is combining all the data from each component into one data set with enough sample size and utilizing the useful information in the censored data. The ROK Navy has been operating multiple Patrol Killer Guided missiles (PKGs) for several years. The Korea Multi-Function Control Console (KMFCC) is one of key components in PKG combat system. The maintenance record for the KMFCC contains less than ten failure observations and a censored datum. This paper proposes a Bayesian approach with a Dirichlet mixture model to estimate failure time density for KMFCC. Trends test for each component record indicated that null hypothesis, that failure occurrence is renewal process, is not rejected. Since the KMFCCs have been functioning under different operating environment, the failure time distribution may be a composition of a number of unknown distributions, i.e. a mixture distribution, rather than a single distribution. The Dirichlet mixture model was coded as probabilistic programming in Python using PyMC3. Then Markov Chain Monte Carlo (MCMC) sampling technique employed in PyMC3 probabilistically estimated the parameters' posterior distribution through the Dirichlet mixture model. The simulation results revealed that the mixture models provide superior fits to the combined data set over single models.

• IMMUNE NETWORK
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• v.5 no.3
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• pp.157-162
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• 2005

Background: 1-8D gene is a member of human 1-8 interferon inducible gene family and was shown to be overexpressed in fresh colon cancer tissues. Three peptides 1-6, 3-5 and 3-7 derived from human 1-8D gene were shown to have immunogenicity against colon cancer. Methods: To study tumor immunotherapy, of three peptides we established an active immunization model using HHD mice. $D^{b-/-}{\times}{\beta}2$ microglobulin $({\beta}2m)$ null mice transgenic for a chimeric HLA-$A2.1/D^{b-}\;{\beta}2m$ single chain (HHD mice) were challenged with B16/HHD/1-8D tumor cells and were immunized with irradiated peptide-loaded RMA- S/HHD/B7.1 transfectants. In therapy model tumor growth was retarded in HHD mice that were injected with 3-5 peptide-loaded RMA-S/HHD/B7.1. In survival test vaccination with 1-8D-derived peptide protects HHD mice from tumor progression after tumor challenge. Results: These studies show that peptide 3-5 derived from 1-8D gene can be the most effective candidate for the vaccine of immunotherapy against colon cancer and highlight 1-8D gene as putative colon carcinoma associated antigens. Conclusion: We demonstrated that RMA-S/HHD/ B7.1 loaded with 1-8D peptides, especially 3-5, immunization generates potent antitumor immunity against tumor cells in HHD mice and designed active immunization as proper immunotherapeutic protocols.