• Proceedings of the Korean Society of Computer Information Conference
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• 2023.07a
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• pp.283-285
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• 2023

이상 탐지는 데이터에서 일반적인 범주에서 크게 벗어나는 인스턴스 또는 패턴을 식별하는 중요한 작업이다. 본 연구에서는 시계열 데이터의 특징 추출을 위한 비지도 학습 기반 방법과 정규화 흐름의 결합을 통한 이상 탐지 프레임워크를 제안한다. 특징 추출기는 1차원 합성곱 신경망 기반의 오토인코더로 구성되며, 정상적인 시퀀스로만 구성된 훈련 데이터를 압축하고 복원하는 과정을 통해 최적화된다. 추출된 시계열 데이터의 특징 맵은 가능도를 최대화하도록 훈련된 정규화 흐름의 입력으로 사용된다. 이와 같은 방식으로 훈련된 이상 탐지 시스템은 테스트 샘플에 대한 이상치를 계산하며, 최종적으로 임계값과의 비교를 통해 이상 여부를 예측한다. 성능 평가를 위해 시계열 이상 탐지를 위한 공개 데이터셋을 이용하여 공정하게 이상 탐지 성능을 비교하였으며, 실험 결과는 제안하는 정규화 흐름 기법이 시계열 이상 탐지 시스템에 활용될수 있는 잠재성을 시사한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.6
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• pp.1516-1529
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• 2023

In this paper, a motor gearbox fault-detection system based on a hierarchical flow-based model is proposed. The proposed system is used for the anomaly detection of a motion sound-based actuator module. The proposed flow-based model, which is a generative model, learns by directly modeling a data distribution function. As the objective function is the maximum likelihood value of the input data, the training is stable and simple to use for anomaly detection. The operation sound of a car's side-view mirror motor is converted into a Mel-spectrogram image, consisting of a folding signal and an unfolding signal, and used as training data in this experiment. The proposed system is composed of an encoder and a decoder. The data extracted from the layer of the pretrained feature extractor are used as the decoder input data in the encoder. This information is used in the decoder by performing an interlayer cross-scale convolution operation. The experimental results indicate that the context information of various dimensions extracted from the interlayer hierarchical data improves the defect detection accuracy. This paper is notable because it uses acoustic data and a normalizing flow model to detect outliers based on the features of experimental data.

• Journal of Advanced Research in Ocean Engineering
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• v.2 no.4
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• pp.169-178
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• 2016

Recently, artificial reefs (ARs) have been frequently used primarily owing to the development in AR materials and projects for relatively complicated, large ARs. Among several engineering issues of ARs, wake region of an AR has been characterized because these regions have a high probability of recruiting seaweed spores, providing an energy saving zone, and facilitating deposition of sediments, nutrients, and bio-deposits. To characterize an efficiency index of an AR wake region and its dependency on the prevailing water flow directions, this study proposes a so-called efficiency index diagram. This characterization is done by normalizing the wake volumes with respect to the real AR volume and illustrating how efficiency indices vary with respect to the inlet flow directions. As a result, according to the diagram characteristics such as an averaged efficiency index, fundamental symmetric angle, secure angles, and principal directions, we can easily figure out how a target AR should be aligned along the main water flows to maximize the wake region around the AR. In addition, six ARs are considered and their efficiency index diagrams are illustrated to pinpoint the physical characteristics.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.4
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• pp.283-289
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• 2013

This study was designed to evaluate the protective effect of Korean red ginseng (KRG) against ischemia/reperfusion (I/R) injury in isolated guinea pig heart. KRG has been shown to possess various ginsenosides, which are the major components of Panax ginseng. These components are known naturally occurring compounds with beneficial effects and free radical scavenging activity. The heart was induced to ischemia for 60 min, followed by 120 min reperfusion. The hearts were randomly allocated into five groups (n=8 for each group): normal control (N/C), KRG control, I/R control, 250 mg/kg KRG group and 500 mg/kg KRG group. KRG significantly increased hemodynamics parameters such as aortic flow, coronary flow and cardiac output. Moreover, KRG significantly increased left ventricular systolic pressure (LVSP), the maximal rate of contraction (+dP/$dt_{max}$) and maximal rate of relaxation (-dP/$dt_{max}$). Also, treatment of KRG ameliorated electrocardiographic index such as the QRS, QT and RR intervals. Moreover, KRG significantly suppressed the lactate dehydrogenase, creatine kinase-MB fraction and cardiac troponin I and ameliorated the oxidative stress markers such as malondialdehyde and glutathione. KRG was standardized through ultra performance liquid chromatograph analysis for its major ginsenosides. Taken together, KRG has been shown to prevent cardiac injury by normalizing the biochemical and oxidative stress.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2447-2451
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• 2013

Objective: To study changes of tumor associated carbohydrate antigen (TACAs) expression and mRNA levels for tumor associated glycosyltransferases, and assess subcellular localizations of N-acetyl galactosyltransferases (GalNAc-Ts) in the K562 leukemia cell line after imatinib treatment. Methods: RT-PCR was performed to analyze the expression of glycosyltransferases which synthesize O-glycan in tumor-associated carbohydrate antigens (TCTAs). The expression of Tn antigen, T antigen and sialyl T antigen on K562 cell membranes was measured by flow cytometry after treatment with different concentrations of imatinib. Co-localization of GalNAc-Ts and ER (endoplasmic reticulum) was determined by confocal laser scanning microcopy. Results: Transcript expression levels of several glycosyltransferases related to TCTAs were decreased after imatinib ($0-0.3{\mu}M$) treatment. Expression of Tn antigen and T antigen was increased while that of sialyl T antigen was decreased. Co-localization of GalNAc-Ts and ER was reduced by $0.2{\mu}M$ of imatinib. Conclusion: Imatinib inhibited the expression of O-glycan related TACAs and several related glycosyltransferases, while decreasing the co-localization of GalNAc-Ts and ER and normalizing O-glycosylation in the K562 human leukemia cell.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.5
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• pp.71-78
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• 2002

Experiments have been performed using two-color PIV in hydrogen non-premixed flames with various conditions of coaxial air, which was classified into three cases with/without reaction. Mean velocity, turbulence intensity and Reynolds stress were analyzed using flow fields from PIV measurement First, the similarity of pure jet had a good agreement with previous results of other researchers. It was found that the decay of centerline velocity was proportional to $x^{-1}$ in coaxial air conditions. By normalizing axial distance with effective jet diameter defined by effective density, the data of centerline velocity collapsed a single line. And the radial profiles of mean velocity showed that they didn't become self-similar because the curves differed from each other as coaxial air velocity increased at fixed fuel velocity. Also, turbulence intensity became self-similar further downstream than mean velocity.

• Journal of Ginseng Research
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• v.48 no.2
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• pp.190-201
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• 2024

Background: Deposition of immune complexes drives podocyte injury acting in the initial phase of lupus nephritis (LN), a process mediated by B cell involvement. Accordingly, targeting B cell subsets represents a potential therapeutic approach for LN. Ginsenoside compound K (CK), a bioavailable component of ginseng, possesses nephritis benefits in lupus-prone mice; however, the underlying mechanisms involving B cell subpopulations remain elusive. Methods: Female MRL/lpr mice were administered CK (40 mg/kg) intragastrically for 10 weeks, followed by measurements of anti-dsDNA antibodies, inflammatory chemokines, and metabolite profiles on renal samples. Podocyte function and ultrastructure were detected. Publicly available single-cell RNA sequencing data and flow cytometry analysis were employed to investigate B cell subpopulations. Metabolomics analysis was adopted. SIRT1 and AMPK expression were analyzed by immunoblotting and immunofluorescence assays. Results: CK reduced proteinuria and protected podocyte ultrastructure in MRL/lpr mice by suppressing circulating anti-dsDNA antibodies and mitigating systemic inflammation. It activated B cell-specific SIRT1 and AMPK with Rhamnose accumulation, hindering the conversion of renal B cells into plasma cells. This cascade facilitated the resolution of local renal inflammation. CK facilitated the clearance of deposited immune complexes, thus reinstating podocyte morphology and mobility by normalizing the expression of nephrin and SYNPO. Conclusions: Our study reveals the synergistic interplay between SIRT1 and AMPK, orchestrating the restoration of renal B cell subsets. This process effectively mitigates immune complex deposition and preserves podocyte function. Accordingly, CK emerges as a promising therapeutic agent, potentially alleviating the hyperactivity of renal B cell subsets during LN.

• Journal of Korean Medical classics
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• v.37 no.2
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• pp.11-30
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• 2024

Objectives : Not many studies have been done on the mechanism of the Gangeum or Gangpyoeum method which treats the Soyang Exterior Pattern, nor on which collective or individual roles the Gangeum medicinals play. Therefore in this study, four medicinals categorized as Gangpyoeum which are Jingjie, Fangfeng, Qianghuo, Duhuo, were analyzed in terms of their individual and collective effects. Methods : Content analysis based on the verses in the Donguisusebowon, and medicinal analysis on contents from the Donguibogam, Bencaogangmu, and Benjingshuzheng were carried out followed by a medicinal combination analysis using the InSAm 1.1 program. Results : The four medicinals Jingjie, Fangfeng, Qianghuo, Duhuo had the common effect of normalizing the Wei qi, allowing for unobstructed Qi flow to prevent production of dampness and phlegm, which ultimately lowers Yin[降陰, gangeum] and helps to preserve the Kidney Yin Qi. Jingjie works at the highest position of the upper body; Fangfeng, the most basic medicinal of the Soyangin pattern, works mostly at the upper body although it defends the entire body from wind-dampness. Qianghuo and Duhuo are more or less similar. The difference is that Qianghuo mostly pulls Yang qi upwards while eliminating pathological byproducts, and Duhuo stabilizes the lower body that pulls Wei qi upwards. Conclusions : Analysis on the relationship between Gangpyoeum of the Soyangin pattern and Wei qi, the individual and collective effects of the four Gangpyoeum medicinals were carried out. Further research on other major Soyangin medicinals, along with those of other constitution patterns is anticipated.

• Journal of Korea Water Resources Association
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• v.54 no.8
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• pp.629-641
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• 2021

In this study, a two-dimensional numerical model (Nays2DH) was applied to analyze the process of morphological changes in the river channel bed depending on the changes in the amount of flooding after fully opening the Sejong weir, which was constructed upstream of the Geum River. For this, numerical simulations were performed by assuming the flow conditions, such as a non-uniform flow (NF), unsteady flows (single flood event, SF), and a continuous flood event (CF). Here, in the cases of the SF and CF, the normalized hydrograph was calculated from real flood events, and then the hydrograph was reconfigured by the peak flow discharge according to the scenario, and then it was employed as the flow discharge at the upstream boundary condition. In this study, to quantitatively evaluate the morphological changes, we analyzed the time changes in the bed deformation the bed relief index (BRI), and we compared the aerial photographs of the study area and the numerical simulation results. As simulation results of the NF, when the steady flow discharge increases, the ratio of lower width to depth decreases and the speed of bar migration increases. The BRI initially increases, but the amount of change decreased with time. In addition, when the steady flow discharge increases, the BRI increased. In the case of SF, the speed of bar migration decreased with the change of the flow discharge. In terms of the morphological response to the peak flood discharge, the time lag also indicated. In other words, in the SF, the change of channel bed indicates a phase lag with respect to the hydraulic condition. In the result of numerical simulation of CF, the speed of bar migration depending on the peak flood discharges decreased exponentially despite the repeated flood occurrences. In addition, as in the result of SF, the phase lag indicated, and the speed of bar migration decreased exponentially. The BRI increased with time changes, but the rate of increase in the BRI was modest despite the continuous peak flooding. Through this study, the morphological changes based on the hydrological characteristics of the river were analyzed numerically, and the methodology suggested that a quantitative prediction for the river bed change according to the flow characteristic can be applied to the field.

• Journal of Embryo Transfer
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• v.24 no.3
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• pp.225-230
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• 2009

Sex-sorting of sperm is an assisted reproductive technology (ART) used by the livestock industry for the mass production of animals of a desired sex. The standard method for sorting sperm is the detection of DNA content differences between X and Y chromosome-bearing sperm by flow cytometry. However, this method has variable efficiency and therefore requires verification by a second method. We have developed a sex determination method based on quantitative real-time polymerase chain reaction (qPCR) of the porcine amelogenin (AMEL) gene. The AMEL gene is present on both the X and the Y chromosome, but the length and sequence of its noncoding regions differ between the X and Y chromosomes. By measuring the threshold cycle (Ct) of qPCR, we were able to calculate the relative frequency of X chromosome. Two sets of AMEL primers were used in these studies. One set (AME) targeted AMEL gene sequences present in both X and Y chromosome, but produced PCR products of different lengths for each chromosome. The other set (AXR) bound to AMEL gene sequences present on the X chromosome but absent esholthe Y-chromosome. Relative product levels were calculated by normalizing the AXR fluorescence to the AME fluorescence. The AMEL method accurately predicted the sex ratios of boar sperm, demonstrating that it has potential value as a sex determination method.