• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.423-429
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• 2018

Objective: This study was conducted to investigate the effects of WBVE on biomechanical factor analysis of drop landing jumps before and after a four week training program. Methods: Participants were divided into two group: VEG (n=5, age: $25.7{\pm}2.3yrs$, height: $170{\pm}7.6cm$, weight: $69.3{\pm}8.3kg$) and OEG (n=5, age: $24.6{\pm}3.4yrs$, height: $164{\pm}4.9cm$, weight: $58.8{\pm}9.2kg$). Ten infrared cameras (Vicon, UK) with a sampling rate of 100 Hz were used in two GRF measurement systems (AMTI, USA). Results: The variability of the center of mass was largest at the falling phase, and there was a great risk of injury when landing after the jump. Second, the jumping heights of the VEG (vibration exercise group) were higher than those of the OEG (only exercise group), regardless of training period. Third, there were significant differences in the hip joint P1 (flexion) and knee joint P2 (extension) between the exercise groups after 4 weeks of training. However, there were no significant differences among training periods or phases. Conclusion: regardless of training periods, the VEG showed increased jump height compared with the OEG, but the consistency between the jump height and the lower joint power could not be determined.

• Journal of the Korean earth science society
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• v.31 no.4
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• pp.301-312
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• 2010

Geochemical data have been regarded as one of the important environmental variables in the environmental management. Since they are often sampled at sparse locations, it is important not only to predict attribute values at unsampled locations, but also to assess the uncertainty attached to the prediction for further analysis. The main objective of this paper is to exemplify how indicator geostatistics can be effectively applied to geochemical data processing for providing decision-supporting information as well as spatial distribution of the geochemical data. A whole geostatistical analysis framework, which includes probabilistic uncertainty modeling, classification and risk analysis, was illustrated through a case study of cadmium mapping. A conditional cumulative distribution function (ccdf) was first modeled by indicator kriging, and then e-type estimates and conditional variance were computed for spatial distribution of cadmium and quantitative uncertainty measures, respectively. Two different classification criteria such as a probability thresholding and an attribute thresholding were applied to delineate contaminated and safe areas. Finally, additional sampling locations were extracted from the coefficient of variation that accounts for both the conditional variance and the difference between attribute values and thresholding values. It is suggested that the indicator geostatistical framework illustrated in this study be a useful tool for analyzing any environmental variables including geochemical data for decision-making in the presence of uncertainty.

• Analytical Science and Technology
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• v.30 no.6
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• pp.348-354
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• 2017

In this study, patterns of proteome expression were monitored and specifically expressed proteins in human milk were detected in collected human milk after 1 week, 3 weeks, and 6 weeks from delivery. A quantitative shotgun proteomic approach was used to identify human milk proteins and reveal their relative expression amounts. For each sample, two independent human milk samples from two mothers were pooled, and then three replicated shotgun proteomic analyses were carried out. Casein, which is a highly abundant protein in human milk, was removed, and then trypsin was treated to produce a digested peptide mixture. The peptides were loaded in the home-made reversed-phase C18 fused-silica capillary column, and then the eluted peptides were analyzed by using a linear ion-trap mass spectrometer. The relative quantitation of proteins was performed by the normalized spectral count method. For each sample, 81-109 non-redundant proteins were identified. The identified proteins consisted of glycoproteins, metabolic enzyme, and chaperon enzymes such as lactoferrin, carboxylic ester hydrolase, and clusterin. The comparative analysis for the 63 proteins, which were reproducibly identified in all three replications, revealed that 25 proteins were statically significant differentially expressed. Among the differentially expressed proteins, Ig lambda-7 chain C region and tenascin drastically decreased with the delivery time.

• Food Science of Animal Resources
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• v.28 no.5
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• pp.616-622
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• 2008

Listeria monocytogenes is a foodborne pathogen inducing listeriosis in human. We compared two different culture methods for detection of L. monocytogenes and validated two commercial kits, $VIDAS^{(R)}$ and $REVEAL^{(R)}$ for Listeria. L. monocytogenes was inoculated into various food samples to generate partial positive samples. The inoculated samples were enriched in half-Fraser broth for 48 hr at $30^{\circ}C$. The enriched samples were streaked onto Oxford agar at 24 and 48 hr postincubation followed by biochemical confirmation and concurrently analyzed by using the two commercial kits for comparison. When the enrichment period was extended from 24 to 48 hr, the numbers of positive samples were dramatically increased from 6 to 52 out of 80 samples tested using the culture method. With the commercial kits, the numbers of positive samples were also significantly increased from 10 to 18 and 1 to 18, respectively, when the enrichment period was extended from 48 to 72 hr. There was no statistical difference between the 24 hr culture method and $VIDAS^{(R)}$ or $Reveal^{(R)}$ with 48 hr enrichment. In conclusion, the 24 hr for the culture method was insufficient to detect L. monocytogenes in various foods. The commercial kits could be adequate means for presumptive screening of L. monocytogenes in food.

• Journal of Wetlands Research
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• v.20 no.4
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• pp.314-321
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• 2018

In order to quantify nonpoint source pollution, it was proposed to sample at regular intervals of 1 hour for the first 24 hours of storm runoff process by National Institute of Environmental Research for the mixed landuse watershed. However, high frequency sampling requires intensive laboratory analysis and labor costs. In order to investigate the effect of longer sampling interval on the load estimation compared to the 1 hour sampling method, analysis was conducted using monitoring data from rural subwatershed, urban subwatershed, and outlet of the Pungyeongjeongcheon watershed. Statistical analysis revealed that mean of load estimation was not significantly different up to 4 hour sampling frequency. However, 3 hour sampling interval was found to be appropriate for the BOD and TP when it is judged that 10% or less of the difference in loading amount between the 1 hour and other sampling interval is reasonable. The results of this study can be used to conduct an effective monitoring system.

• Journal of Soil and Groundwater Environment
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• v.10 no.5
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• pp.52-60
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• 2005

The conceptual model of under-sampled study area will include a great amount of uncertainty. In this study, we investigate the applicability of Markov chain model in a spatial domain as a tool for minimizing the uncertainty arose from the lack of data. A new formulation is developed to generalize the previous two-dimensional coupled Markov chain model, which has more versatility to fit any computational sequence. Furthermore, the computational algorithm is improved to utilize more conditioning information and reduce the artifacts, such as the artificial parcel inclination, caused by sequential computation. A generalized 20 coupled Markov chain (GCMC) is tested through applying a hypothetical soil map to evaluate the appropriateness as a substituting model for conventional geostatistical models. Comparing to sequential indicator model (SIS), the simulation results from GCMC shows lower entropy at the boundaries of indicators which is closer to real soil maps. For under-sampled indicators, however, GCMC under-estimates the presence of the indicators, which is a common aspect of all other geostatistical models. To improve this under-estimation, further study on data fusion (or assimilation) inclusion in the GCMC is required.

• The Korean Journal of Applied Statistics
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• v.33 no.4
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• pp.511-526
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• 2020

Single-cell RNA-sequencing (scRNA-seq) data consists of each cell's RNA expression extracted from large populations of cells. One main purpose of using scRNA-seq data is to identify inter-cellular heterogeneity. However, scRNA-seq data pose statistical challenges when applying traditional clustering methods because they have many missing values and high level of noise due to technical and sampling issues. In this paper, motivated by analyzing scRNA-seq data, we propose a novel spectral-based clustering method by imposing different weights on genes when computing a similarity between cells. Assigning weights on genes and clustering cells are performed simultaneously in the proposed clustering framework. We solve the proposed non-convex optimization using an iterative algorithm. Both real data application and simulation study suggest that the proposed clustering method better identifies underlying clusters compared with existing clustering methods.

• The Journal of the Korea Contents Association
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• v.18 no.2
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• pp.370-377
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• 2018

Focus level has been important mental state in user study. Cardiac response has been related to focus and less clarified. The study was to determine cardiac parameters for recognizing focus level. The sixty participants were asked to play shooting game designed to control two focus levels. Electrocardiogram was measured during task. The parameters of time domain and frequency domain were determined from ECG. As a result of independent t-test, RRI, SDNN, rMSSD and pNN50 of time domain indicator were statistically significant in recognizing focus level. LF, HF, lnLF and lnHF of frequency domain were observed to be significant indicator. The rule base for recognition has been developed by the combination of RRI, rMSSD and lnHF. The rule base has been verified from another sixty data samples. The recognition accuracy were 95%. This study proposed significant cardiac indicators for recognizing focus level. The results provides objective measurement of focus in user interaction design in the fields of contents industry and service design.

• Convergence Security Journal
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• v.6 no.3
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• pp.117-126
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• 2006

Bayesian inference and model selection method for software reliability growth models are studied. Software reliability growth models are used in testing stages of software development to model the error content and time intervals between software failures. In this paper, could avoid multiple integration using Gibbs sampling, which is a kind of Markov Chain Monte Carlo method to compute the posterior distribution. Bayesian inference for general order statistics models in software reliability with diffuse prior information and model selection method are studied. For model determination and selection, explored goodness of fit (the error sum of squares), trend tests. The methodology developed in this paper is exemplified with a software reliability random data set introduced by of Weibull distribution(shape 2 & scale 5) of Minitab (version 14) statistical package.

• Journal of Periodontal and Implant Science
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• v.36 no.2
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• pp.397-408
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• 2006

치주질환은 치아 지지조직의 파괴로 튿정 지어지는 감염성 질환으로서 이것은 주로 조직의 교원질 성분을 분해시키는 MMP(matrix metalloproteinase)에 의해 이루어진다. 한편, 여러 연구에서 당뇨병과 치주질환의 심도와의 관계에 대한 논의가 있어왔으며 당뇨병이 치주염을 포함한 구강 감염에 대한 감수성을 증가시키며 역으로 만성 치주염의 염증성 매개물질에 의해 인슐린 작용이 방해받을 수 있음을 보고하였다. 본 연구의 목적은 만성 치주염 환자와 제 2형 당뇨병을 동반한 만성 치주염 환자의 치은조직에서 MMP-13과 elastase의 발현 양상을 비교하여 병리 기전의 차이점을 규명하고, 두 단백질간의 상호관계를 알아보기 위한 것이다. 경북대 병원 치주과에 내원한 환자의 비당뇨 환자의 정상 치은 부위, 비당뇨 환자의 만성 치주염 부위, 제 2형 당뇨병 환자의 만성 치주염 부위에서 각각 8개의 변연 치은을 채득하여 액화 질소에 급속 동결시켰다. 모든 조직 샘플에서 동량의 단백질을 western blotting을 통해 분석하여였고, densitometer를 이용하여 정량한 후 ANOVA 분석으로 통계처리 하였다. 결과분석에서 MMP-13은 제 2형 당뇨를 가진 환자의 염증성 조직에서 가장 높게 발현되었고 전신적으로 건강한 환자의 염증성 조직과 정상 조직에서는 유사한 양상을 보였으며 그 차이는 통계적으로 유의하였다. 또한 elastas는 그룹간에 유의한 차이 없이 유사한 양상으로 발현되었고, 염증성 조직에서도 당뇨병의 유무에 관계없이 유사하게 나타났다. 한편 조직내 MMP-13과 elastase의 발현 양상간에 유의한 상관관계는 보이지 않았다. 결론적으로 MMP-13은 당뇨병을 동반한 환자의 치은 염증초직에서 유의하게 증가되어 나타났으며, 전신적으로 건강한 환자의 염증조직과 당뇨를 동반한 환자의 염증조직에서 MMP-13과 elastase의 발현양상은 큰 상관관계가 발견되지 않았다.