• Genomics & Informatics
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• v.8 no.3
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• pp.122-130
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• 2010

Abnormal hematological values are associated with various disorders including cancer and cardiovascular, metabolic, infectious, and immune diseases. We report the copy number variations (CNVs) in clinically relevant hematological parameters, including hemoglobin level, red and white blood cell counts, platelet counts, and red blood cell (RBC) volume. We describe CNVs in several loci associated with these hematological parameters in 8,842 samples from Korean population-based studies. The data that we evaluated included four RBC parameters, one platelet parameter, and one associated with total white blood cell (WBC) count, exceeding the genome-wide significance. We show that CNVs in hematological parameters are associated with some loci, different from previously associated loci reported in single nucleotide polymorphism (SNP) association studies.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.86-89
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• 2004

To estimate a electrical performance of the extra high voltage XLPE cable the discharge properties due to shift of void position were investigated. The ${\phi}-q-n$ properties have been measured at room temperature by rising voltage ratio of 0.5[kV]. An obtained data was stored to personal computer through A/D converter. The period of applied wave form and discharge values were divided into 64 parts and discharge values generated during 10 seconds were accumulated by phases. As a result, it was confirmed that the charge, phase angle and counts of discharge changed due to void position.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.256-257
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• 2005

To estimate a electrical performance of the extra high voltage XLPE cable the discharge properties due to shift of void position were investigated. The $\Phi-q-n$ properties have been measured at room temperature by rising voltage ratio of 0.5[kV]. An obtained data was stored to personal computer through A/D converter. The period of applied wave form and discharge values were divided into 64 parts and discharge values generated during 10 seconds were accumulated by phases. As a result, it was confirmed that the charge, phase angle and counts of discharge changed due to void position.

• The Korean Journal of Applied Statistics
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• v.30 no.1
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• pp.181-193
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• 2017

The paper introduces bottom-up and optimal combination methods that can analyze and forecast hierarchical time series. These methods allow forecasts at lower levels to be summed consistently to upper levels without any ad-hoc adjustment. They can also potentially improve forecast performance in comparison to independent forecasts. We forecast regional traffic accident counts as time series data in order to identify efficiency gains from hierarchical forecasting. We observe that bottom-up or optimal combination methods are superior to independent methods in terms of forecast accuracy.

• Mass Spectrometry Letters
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• v.12 no.2
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• pp.47-52
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• 2021

Evaluating the impurity concentrations in semiconductor thin films using time of flight secondary ion mass spectrometry (ToF-SIMS) is an effective technique. The mass interference between isotopes and matrix element in data interpretation makes the process complex. In this study, we have investigated the doping concentration of phosphorus in, phosphorus doped silicon thin film on glass using ToF-SIMS in the dynamic mode of operation. To overcome the mass interference between phosphorus and silicon isotopes, the quantitative analysis of counts to concentration conversion was done following two routes, standard relative sensitivity factor (RSF) and SIMetric software estimation. Phosphorus doped silicon thin film of 180 nm was grown on glass substrate using hot wire chemical vapor deposition technique for possible applications in optoelectronic devices. Using ToF-SIMS, the phosphorus-31 isotopes were detected in the range of 10¹~10⁴ counts. The silicon isotopes matrix element was measured from p-type silicon wafer from a separate measurement to avoid mass interference. For the both procedures, the phosphorus concentration versus depth profiles were plotted which agree with a percent difference of about 3% at 100 nm depth. The concentration of phosphorus in silicon was determined in the range of 10¹⁹~10²¹ atoms/cm³. The technique will be useful for estimating distributions of various dopants in the silicon thin film grown on glass using ToF-SIMS overcoming the mass interference between isotopes.

• Journal of muscle and joint health
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• v.29 no.2
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• pp.91-99
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• 2022

Purpose: The purpose of this study was to examine the level of agreement between smartphone apps and self-reported physical activity questionnaires. Methods: Quantitative methods were used to assess the correlation and agreement between the number of steps counted by a smartphone app and the amount of walking reported in a survey. A total of 29 adults who used smartphones were recruited from a university, and their step counts from their smartphone pedometers and responses to the international physical activity questionnaire (IPAQ) were collected over a 10-week period. Results: An analysis of 170 data pairs with Spearman's rho correlation and a Bland-Altman plot revealed a positive correlation between step counts from the smartphone app and walking activity from the IPAQ. The Bland-Altman plot also demonstrated the agreement to be improved among female participants. Conclusion: In assessing walking activity, smartphone pedometer apps showed good correlation with the IPAQ and improved agreement with the IPAQ among women. Therefore, it is suggested that the participants' gender and activity intensity, as well as the accuracy of measurement tools, should be considered in an evaluation of the delivery of physical activity promotion programs through smartphone apps.

• Clinical and Experimental Reproductive Medicine
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• v.51 no.2
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• pp.120-124
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• 2024

Objective: Seasonal variations in semen quality are known to occur in temperate regions, but results regarding tropical areas remain inconclusive. The aim of this study was to determine whether monthly variations in semen parameters are present among men in a tropical region. Methods: Data were retrospectively collected from semen analyses of 3,000 men over a 10-year period, from 2012 to 2022. Analysis of variance and the independent-samples t-test were employed to observe variations in semen parameters throughout the entire period and between months, respectively. Results: The mean±standard deviation sperm concentration was significantly lower in June, at 42.5±31.4 million/mL, compared to other months. The highest sperm concentration was found in March, at 57.8±42.6 million/mL, constituting a mean difference of 15.3 million/mL between the lowest and highest concentrations. The total sperm count displayed a similar pattern of monthly variation, with a difference of 47.2 million between the highest and lowest months. No significant monthly differences were observed in other parameters, such as sperm motility, morphology, and semen volume. Conclusion: Significant monthly variations in sperm concentration and total sperm count were evident in this Sri Lankan population. March, which displayed the highest sperm counts, is in the spring in temperate regions, while the month with the lowest counts, July, is part of the summer. Fluctuations in photoperiod appear to most strongly influence these variations.

• Communications for Statistical Applications and Methods
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• v.23 no.5
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• pp.433-444
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• 2016

When we observe binary responses in a cluster (such as rat lab-subjects), they are usually correlated to each other. In clustered binomial counts, the independence assumption is violated and we encounter an extra-variation. In the presence of extra-variation, the ordinary statistical analyses of binomial data are inappropriate to apply. In testing the homogeneity of proportions between several treatment groups, the classical Pearson chi-squared test has a severe flaw in the control of Type I error rates. We focus on modifying the chi-squared statistic by incorporating variance inflation factors. We suggest a method to adjust data in terms of dispersion estimate based on a quasi-likelihood model. We explain the testing procedure via an illustrative example as well as compare the performance of a modified chi-squared test with competitive statistics through a Monte Carlo study.

• Journal of the Korean Data and Information Science Society
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• v.27 no.5
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• pp.1225-1239
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• 2016

We investigate pediatric tumor incidence data collected by the Florida Association for Pediatric Tumor program using various models commonly used in disease mapping analysis. Particularly, we consider Poisson normal models with various conditional autoregressive structure for spatial dependence, a zero-in ated component to capture excess zero counts and a spatio-temporal model to capture spatial and temporal dependence, together. We found that intrinsic conditional autoregressive model provides the smallest Deviance Information Criterion (DIC) among the models when only spatial dependence is considered. On the other hand, adding an autoregressive structure over time decreases DIC over the model without time dependence component. We adopt weighted ranks squared error loss to identify high risk regions which provides similar results with other researchers who have worked on the same data set (e.g. Zhang et al., 2014; Wang and Rodriguez, 2014). Our results, thus, provide additional statistical support on those identied high risk regions discovered by the other researchers.

• The Korean Journal of Nuclear Medicine
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• v.29 no.4
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• pp.478-483
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• 1995

We compared the influences of reconstruction methods using $180^{\circ}$ or $360^{\circ}$ data upon contrasts and discriminating capability and diagnostic accuracy in $^{99m}Tc-MIBI$ stress/rest myocardial SPECT. We reviewed SPECT images reconstructed only with $180^{\circ}$ projection data or with $360^{\circ}$ data in 18 patients and in 11 normal subjects. To compare counts of surface structures and deep structures, we measured ape# posterior wall ratios in 11 normal subjects. To compare the contrasts of images, we measured apex/ventricle ratios. To compare contrasts between normal and diseased myocardial segments, we measured count ratios of defect and normal segments in 4 patients who had single coronary artery diseases. To compare diagnostic accuracy, we scored SPECT images made with $180^{\circ}$ and $360^{\circ}$ data segmentally. Sensitivity and specificity for the diagnosis of coronary artery disease and for the revelation of diseased arteries with both $180^{\circ}$ and $360^{\circ}$ SPECT images. If involved coronary arteries had more narrowing than 50% In coronary angiogram, we considered them as diseased arteries Apex/posterior wall ratios were not different significantly in normal subjects. Apex/ ventricle ratios in normal subjects were different significantly between $180^{\circ}$ and $360^{\circ}$ SPECT images. Defect/normal ratios were different significantly between $180^{\circ}$ and $360^{\circ}$ SPECT images in single vessel disease patients. The overall diagnostic accurracy was the same between $180^{\circ}$ and $360^{\circ}$ data collection. Sensitivity was 94% and specificity was 91% for both types of data collection in this sample population. Sensitivity and specificity of each coronary artery territory were not significantly different between the images made with $180^{\circ}$ and $360^{\circ}$ data. The images made with $180^{\circ}$ data had better contrast between ventricle and myocardium and between hypoperfused and normal myocardium, though no difference was found between the ratios of the myocardial counts of surface and deep structures. However, diagnostic sensitivities of diseased artery territories were not different significantly and so were overall diagnostic accuracy between both methods of making images with $180^{\circ}$ and $360^{\circ}$ data.