• Genomics & Informatics
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• v.17 no.4
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• pp.47.1-47.12
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• 2019

The achievements of genome-wide association studies have suggested ways to predict diseases, such as type 2 diabetes (T2D), using single-nucleotide polymorphisms (SNPs). Most T2D risk prediction models have used SNPs in combination with demographic variables. However, it is difficult to evaluate the pure additive contribution of genetic variants to classically used demographic models. Since prediction models include some heritable traits, such as body mass index, the contribution of SNPs using unmatched case-control samples may be underestimated. In this article, we propose a method that uses propensity score matching to avoid underestimation by matching case and control samples, thereby determining the pure additive contribution of SNPs. To illustrate the proposed propensity score matching method, we used SNP data from the Korea Association Resources project and reported SNPs from the genome-wide association study catalog. We selected various SNP sets via stepwise logistic regression (SLR), least absolute shrinkage and selection operator (LASSO), and the elastic-net (EN) algorithm. Using these SNP sets, we made predictions using SLR, LASSO, and EN as logistic regression modeling techniques. The accuracy of the predictions was compared in terms of area under the receiver operating characteristic curve (AUC). The contribution of SNPs to T2D was evaluated by the difference in the AUC between models using only demographic variables and models that included the SNPs. The largest difference among our models showed that the AUC of the model using genetic variants with demographic variables could be 0.107 higher than that of the corresponding model using only demographic variables.

• Journal of the Korean Dietetic Association
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• v.20 no.4
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• pp.247-256
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• 2014

This study compared the perception, necessity, and satisfaction of free school foodservice among parents of students with and without access to free school foodservice. The sample included parents of students with access to free school foodservice (FSF group, 250 parents) or paid school foodservice (PSF group, 250 parents) in Taean, Chungnam. With regard to perception of school foodservice, 30% of PSF parents responded that it is a necessary part of school education, whereas 52% of FSF parents considered it as a part of national welfare service; this difference was significant (P<0.001). In terms of positive remarks, most parents in the PSF group highlighted convenience whereas the FSF group answered that their children were penalized; this difference was significant (P<0.001). In addition, 94% of PSF parents and 96.8% of FSF parents indicated that school foodservice is necessary. In terms of the perception of the free school foodservice, more FSF parents (96.4%) than PSF parents (84.4%) answered that they knew free school foodservice well; this difference was significant (P<0.001). With regard to target recipients of the free school foodservice, most parents in the PSF group said that needy students should be selected, whereas the FSF group said that all students should be eligible; this difference was significant (P<0.001). Acceptance of free school foodservice in the FSF group (34.4%) was significantly higher than that in the PSF group (23.2%). Satisfaction with free school foodservice was 3.5 points in the FSF group, which was significantly higher than the 2.9 points in the PSF group (P<0.001). In summary, parents of students with access to free school foodservice showed more positive perception and higher satisfaction than parents of students with paid school foodservice. This study recommends that parents' suggestions be considered and further perception and responses on free school foodservice be investigated.

• Journal of forensic and investigative science
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• v.1 no.1
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• pp.54-71
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• 2006

The definition of Crime Indictable Upon Complaint (CIC) is crimes which can be prosecuted only with complaints from the victim or his/her direct parents. Sex crimes are the representative examples, rapes and indecent assaults. According to the research referenced in this paper, 74% of sex crimes which had been penalized based on Republic of Korea (ROK) Criminal Code amounts rape and indecent assault are CIC. However, only 20% of perpetrators were confined, and the rest received non-confinement or non-prosecution determination. The review of criminal history checks reveals that 67% of the perpetrators had criminal histories and 39% of them had more than three documented offenses. The CIC was established in order to protect the victim's rights and dignity, respecting the victim's opinion regarding the incident. All kinds of sex crimes then should have been the CIC, but those crimes such as Injury Resulting from Rape, Special Rape, Rape by Special Modus Operandi, Sexual Assault among Relatives and Domestic Violence which have to guarantee the opinion of the victims are prescribed as non-CIC. We therefore conclude that the CIC should be abolished. The abolition of CIC will play an important role in crime prevention because severe penalties for sex crimes will be imposed on the perpetrators. In addition, it will help the sex crime victims retrieve their dignity by spreading recognition widely through the community that sexual assault is not only a social assault but an infringement against human rights.

• Journal of Arbitration Studies
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• v.21 no.1
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• pp.87-107
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• 2011

There are two methods to resolve conflicts related to constructions which are through lawsuits and ADR (Alternative Dispute Resolution) just like any other conflicts. Along with the special characteristics pertaining to the conflicts related to constructions, the advantages that ADR is in possession of such as its cost, duration and professionalism, resolving conflicts through ADR has been considered to be more logical than any other options recently. In Korea's case at present, the resolution of conflicts regarding constructions through ADR is mostly dependent on administrative mediation or through arbitration. However, in the case of the administrative mediation, its usage rate is very low due to problems caused by problems in its running and effectiveness. In the case of arbitration, the services of the Korean Commercial Arbitration Board is comparatively used more but because of the fact that arbitration relies on a single trial system and the fact that its executive powers while having the same effectiveness as the final ruling does not get acknowledged leads to the phenomena of avoiding its usage. In addition, in relation to the selective arbitration clause, the problem of effectiveness of the arbitrative agreement is becoming a hindrance to the activation and promotion of the arbitration process. Furthermore, in the case where the ordering body is the government, the public servant involved in the case avoiding the arbitration process because of concerns of being penalized by the internal and external audit within the institution is becoming a problem as well. These problems are not only limited to conflicts regarding constructions and there needs to be actions taken to promote the activation of ADR by enacting a basic law. The more important issue at hand however is offering a resolution measure that would be the most appropriate for users and this could probably be done only through actions such as implementing the American partnering system or the dispute adjudication board system so that they can supervise the resolution of conflicts through mediation, arbitration, and assistance as well as offering consultations regarding conflicts related to constructions.

• Journal of the Korea Institute of Building Construction
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• v.20 no.2
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• pp.163-169
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• 2020

Construction is a typical labor-dependent industry. However, problems related to wage payment, which directly affects the livelihood of workers, have caused other problems in maintaining skilled workers, such as increasing the turnover rate of skilled workers, resulting in a shortage of skilled workers. Against this backdrop, this study was conducted to develop measures to improve the conventional wage payment systems in order to prevent skilled workers from leaving their jobs and to maintain them as workers. It is necessary to make the registration of non-registered small-sized construction companies in Korea mandatory, and to introduce means by which construction companies that hire workers through non-registered agents can be penalized. In addition, the project bank account (PBA) system used in the domestic banking sector can be benchmarked in operating payment systems, an approach that is expected to effectively prevent delayed wage payments in the construction industry.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.73.2-73.2
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• 2011

We present a new database of absorption and emission-line measurements based on the entire spectral atlas from the Sloan Digital Sky Survey (SDSS) 7th data release of galaxies within a redshift of 0.2. Our work makes use of the publicly available penalized pixel-fitting(pPXF) and gas and absorption line fitting (gandalf) IDL codes, aiming to improve the existing measurements for stellar kinematics, the strength of various absorption-line features, and the flux and width of the emissions from different species of ionized gas. Our fit to the stellar continuum uses both standard stellar population models and empirical templates obtained by combining a large number of stellar spectra in order to fit a subsample of high-quality SDSS spectra for quiescent galaxies. Furthermore, our fit to the nebular spectrum includes an exhaustive list of both recombination and forbidden lines. Foreground Galactic extinction is implicitly treated in our models, whereas reddening in the SDSS galaxies is included in the form of a simple dust screen component affecting the entire spectrum that is accompanied by a second reddening component affecting only the ionised gas emission. Most notable of our work is that, we provide quality of the fit to assess reliability of the measurements. The quality assessment can be highly effective for finding new classes of objects. For example, based on the quality assessment around the Ha and [NII] nebular lines, we found approximately 1% of the SDSS spectra which classified as "galaxies" by the SDSS pipeline are in fact type I Seyfert AGN.

• Journal of Environmental Health Sciences
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• v.40 no.5
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• pp.346-354
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• 2014

Objectives: Although a number of epidemiologic studies have examined the association between air pollution and mortality, data limitations have resulted in fewer studies of particulate matter with an aerodynamic diameter of ${\leq}2.5{\mu}m$ ($PM_{2.5}$). We conducted a time-series study of the acute effects of particulate matter with an aerodynamic diameter of ${\leq}10{\mu}m$($PM_{10}$) and $PM_{2.5}$ on the increased risk of death for all causes and cardiovascular mortality in Seoul, Korea from 2006 to 2010. Methods: We applied the generalized additive model (GAM) with penalized splines, adjusting for time, day of week, holiday, temperature, and relative humidity in order to investigate the association between risk of mortality and particulate matter. Results: We found that $PM_{10}$ and $PM_{2.5}$ were associated with an increased risk of mortality for all causes and of cardiovascular mortality in Seoul. A $10{\mu}g/m^3$ increase in the concentration of $PM_{10}$ corresponded to 0.44% (95% Confidence Interval [CI]: 0.25-0.63%), and 0.95% (95% CI: 0.16-1.73%) increase of all causes and of cardiovascular mortality. A $10{\mu}g/m^3$ increase in the concentration of $PM_{2.5}$ corresponded to 0.76% (95% CI: 0.40-1.12%), and 1.63% (95% CI: 0.89-2.37%) increase of all causes and cardiovascular mortality. Conclusion: We conclude that $PM_{10}$ and $PM_{2.5}$ have an adverse effect on population health and that this strengthens the rationale for further limiting levels of $PM_{10}$ and $PM_{2.5}$ in Seoul.

• The Korean Journal of Applied Statistics
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• v.30 no.1
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• pp.135-145
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• 2017

Principal component analysis (PCA) describes the variation of multivariate data in terms of a set of uncorrelated variables. Since each principal component is a linear combination of all variables and the loadings are typically non-zero, it is difficult to interpret the derived principal components. Sparse principal component analysis (SPCA) is a specialized technique using the elastic net penalty function to produce sparse loadings in principal component analysis. When data are structured by groups of variables, it is desirable to select variables in a grouped manner. In this paper, we propose a new PCA method to improve variable selection performance when variables are grouped, which not only selects important groups but also removes unimportant variables within identified groups. To incorporate group information into model fitting, we consider a hierarchical lasso penalty instead of the elastic net penalty in SPCA. Real data analyses demonstrate the performance and usefulness of the proposed method.

• The Korean Journal of Applied Statistics
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• v.32 no.2
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• pp.199-211
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• 2019

This paper is concerned with issues in the finite mixture of regression modeling as well as the simultaneous selection of the number of mixing components and relevant predictors. We propose a penalized likelihood method for both mixture components and regression coefficients that enable the simultaneous identification of significant variables and the determination of important mixture components in mixture of regression models. To avoid over-fitting and bias problems, we applied smoothly clipped absolute deviation (SCAD) penalties on the logarithm of component probabilities suggested by Huang et al. (Statistical Sinica, 27, 147-169, 2013) as well as several well-known penalty functions for coefficients in regression models. Simulation studies reveal that our method is satisfactory with well-known penalties such as SCAD, MCP, and adaptive lasso.

• Korean Journal of Remote Sensing
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• v.37 no.4
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• pp.777-788
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• 2021

Since aerosol has a relatively short duration and significant spatial variation, satellite observations become more important for the spatially and temporally continuous quantification of aerosol. However, optical remote sensing has the disadvantage that it cannot detect AOD (Aerosol Optical Depth) for the regions covered by clouds or the regions with extremely high concentrations. Such missing values can increase the data uncertainty in the analyses of the Earth's environment. This paper presents a spatial gap-filling framework using a univariate statistical method such as DCT-PLS (Discrete Cosine Transform-based Penalized Least Square Regression) and FMM (Fast Matching Method) inpainting. We conducted a feasibility test for the hourly AOD product from AHI (Advanced Himawari Imager) between January 1 and December 31, 2019, and compared the accuracy statistics of the two spatial gap-filling methods. When the null-pixel area is not very large (null-pixel ratio < 0.6), the validation statistics of DCT-PLS and FMM techniques showed high accuracy of CC=0.988 (MAE=0.020) and CC=0.980 (MAE=0.028), respectively. Together with the AI-based gap-filling method using extra explanatory variables, the DCT-PLS and FMM techniques can be tested for the low-resolution images from the AMI (Advanced Meteorological Imager) of GK2A (Geostationary Korea Multi-purpose Satellite 2A), GEMS (Geostationary Environment Monitoring Spectrometer) and GOCI2 (Geostationary Ocean Color Imager) of GK2B (Geostationary Korea Multi-purpose Satellite 2B) and the high-resolution images from the CAS500 (Compact Advanced Satellite) series soon.