• Journal of Korea Water Resources Association
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• v.42 no.12
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• pp.1079-1089
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• 2009

The objective of this study is to develop the accurate, robust and high resolution two-dimensional numerical model that solves the computationally difficult hydraulic problems, including the wave front propagation over dry bed and abrupt change in bathymetry. The developed model in this study solves the conservative form of the two-dimensional shallow water equations using an unsplit finite volume scheme and HLLC approximate Riemann solvers to compute the interface fluxes. Bed-slope term is discretized by the divergence theorem in the framework of FVM for application of unsplit scheme. Accurate and stable SGM, in conjunction with the MUSCL which is second-order-accurate both in space and time, is adopted to balance with fluxes and source terms. The exact C-property is shown to be satisfied for balancing the fluxes and the source terms. Since the spurious oscillations in second-order schemes are inherent, an efficient slope limiting technique is used to supply TVD property. The accuracy, conservation property and application of developed model are verified by comparing numerical solution with analytical solution and experimental data through the simulations of one-dimensional dam break flow without bed slope, steady transcritical flow over a hump and two-dimensional dam break flow with a constriction.

• The Korean Journal of Blood Transfusion
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• v.29 no.3
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• pp.282-290
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• 2018

Background: Anti-E or paired anti-E/-c antibodies can develop in patients with the Rh CDe phenotype. This study examined the differences in transfusion in patients with the CDe phenotype according to formation of anti-E or anti-E/-c antibodies. Methods: Retrospective reviews were carried out on the results of antibody identification tests performed in 2014. The Rh phenotype and antibody specificity were investigated. The transfusion and medical records of patients with the CDe phenotype were examined. Results: In total, 76 patients were included in the review. Of these 76 patients, 38 (50.0%) were of the CDe phenotype. Anti-E antibodies were the most frequent (60.5%), followed by anti-E/-c antibodies (23.7%). The total transfusion units and platelet transfusion units were significantly higher in patients with anti-E/-c antibodies (P=0.028 and P=0.01, respectively). The distribution of categorized diseases was similar in the patients with the anti-E and anti-E/-c antibodies. A frequency of transfusion episodes greater than or equal to four was higher in patients with hepatobiliary diseases (85.7%). Conclusion: In CDe phenotype patients, platelet transfusion was significantly higher in the anti-E/-c positive group than the anti-E positive group, indicating that platelets play a role in red blood cell alloimmunization. Because E is the most immunogenic antigen in Korea, it is important to define the disease group, in which patients with CDe phenotype require a transfusion of E and c-negative blood.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2017.11a
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• pp.77-78
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• 2017

컴퓨터 생성 홀로그램은 방대한 양의 연산이 필요하기 때문에 이를 고속화하기 위한 방법이 필요하다. 본 논문에서는 기존에 본 연구팀에서 ASIC으로 구현했던 홀로그램 생성기의 하드웨어 구조를 보완하여 새로운 하드웨어 구조를 제안한다. 제안하는 하드웨어 구조는 기존의 블록기반의 하드웨어에서 가로축 공통항은 하나만 만들고 세로축 공통항을 확장하고, 블록의 가로축은 시분할을 통하여 계산하도록 제안하고 구현하였다. 제안하는 구조가 더 적은 하드웨어 자원 량으로 같은 성능의 하드웨어를 구현하였고, 입력단의 메모리 접근 량도 줄일 수 있다.

• Annual Conference on Human and Language Technology
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• 2001.10d
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• pp.193-198
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• 2001

본 논문에서는 개정된 국어의 로마자 표기법에 근거한 로마자 표기 변환기를 생성하기 위하여 한글-로마자 표기 변환시스템을 설계하였다. 한글-로마자 표기의 규칙변환을 위하여 로마자 표기법중 표기의 변환에 관련된 항과 그렇지 않은 항으로 분리하여 규칙 변환을 위한 로마자 표기법을 정리하였으며, 로마자 표기법의 근간이 되는 표준 발음법을 페트리넷으로 모델링 후 분석하여 표기-음가 변환표를 생성하고, 표기-음가 변환표에서 로마자 표기법에 해당하지 않는 부분을 제거하여 한글 - 로마자 표기 변환표를 생성하고 이를 바탕으로 한글-로마자 변환 시스템을 구현하였다.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.1
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• pp.85-96
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• 2015

Forsythia fructus has been shown to have antioxidative, anti-inflammatory, antibacterial, anti-aging and whitening effects. This work was carried out to investigate the anti-aging effects of Forsythia viridissima-prescription extracts (Yeongyoseungma-tang, Gamiyeongyoseungma-tang, Hoechunyangkyeok-san) on skin. Skin anti-aging effect of Forsythia viridissima-prescription extracts (Yeongyoseungma-tang, Gamiyeongyoseungma-tang, Hoechunyangkyeok-san) was evaluated by using antioxidant assay, anti-glycation activity, inhibitory effect of tyrosinase activity, expression of type I procollagen and UVA-induced matrix metalloproteinase-1 on HS68 cells, and reduction of ${\alpha}$-MSH-induced melanin on B16F1 cells. Forsythia viridissima-prescription extracts showed anti-oxidative and anti-glycation activity. The pectinex hydrolysed extract from Yeongyoseungma-tang 75% EtOH extract and Gamiyeongyoseungma-tang 75% EtOH extract increased the type I procollagen synthesis, and decreased the UVA-induced MMP-1 expression on HS68 cells. The pectinex hydrolysed extracts of Hoechunyangkyeok-san 75% EtOH extract had the inhibitory effect of melanin synthesis on B16F1 cells. Based on these results, we suggest that Forsythia viridissima-prescription extracts may be useful as a potential source of functional anti-aging cosmetics.

• Korean Journal of Microbiology
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• v.52 no.4
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• pp.482-486
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• 2016

Inonotus obliquus is a medicinal mushroom with a variety of biological activities. It has reported to have strong anti-cancer, antioxidant and anti-inflammatory properties. EBV+ gastric carcinoma is one of the most common EBV-associated cancers that were caused by latent EBV infection. In this study, we investigated the anti-cancer effects of ethanol extract of I. obliquus using in vivo xenograft animal models implanted with EBV+ human gastric carcinoma (SNU719). We also explored the molecular mechanisms responsible for its anti-cancer activity. The result indicated that the extract of I. obliquus had an anti-cancer effect in in vivo xenograft mice with EBV+ gastric carcinoma (SNU719). Extract of I. obliquus also showed a great effect on inducing the expression of p53, p21 and Bax in tumor tissue derived from EBV+ human gastric carcinoma, and these were correlated with increased expressions of the cleaved forms of caspase-9 and Parp. Also, I. obliquus attenuated the expression of viral proteins, BZLF-1 and LMP-2 in tumor tissue from EBV+ human gastric carcinoma.

• Journal of the Society of Naval Architects of Korea
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• v.31 no.3
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• pp.80-86
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• 1994

A numerical method for simulations of inviscid incompressible flow fields around a ship advancing on the free surface is developed. A body fitted coordinate system, generated by numerically solving elliptic type partial differential equations is used to conform the ship and free surface configurations. Three dimensional Euler equations transformed to the non-staggered body fitted coordinate system are discretised by finite difference method. Time and spatial derivatives are discretised by forward and centered differencings, respectively, and artificial dissipations are added to discretised convection terms for improvements of numerical stability. At each time steps, free surface elevations are recomputed to satisfy nonlinear free surface conditions. Poisson equations for pressure field are solved iteratively and the velocity field for next time step is extrapolated. To verify the developed numerical method, flow fields around a Wigley model are simulated(Fn=0.250-0.408) and compared with experimental data to show good agreements.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.06a
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• pp.383-384
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• 2022

Following the development of technologies such as digital twin, IoT, and AI after the 4th industrial revolution, decision-making problems are being solved based on high-dimensional data analysis. This has recently been applied to the port logistics sector, and a number of studies on big data analysis, deep learning predictions, and simulations have been conducted on container terminals to improve port productivity. These high-dimensional data analysis techniques generally require a large number of data. However, the global port environment has changed due to the COVID-19 pandemic in 2020. It is not appropriate to apply data before the COVID-19 outbreak to the current port environment, and the data after the outbreak was not sufficiently collected to apply it to data analysis such as deep learning. Therefore, this study intends to present a port data augmentation method for data analysis as one of these problem-solving methods. To this end, we generate the container stowage situation of the yard through a generative adversarial neural network model in terms of container terminal operation, and verify similarity through statistical distribution verification between real and augmented data.

• Journal of Food Hygiene and Safety
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• v.8 no.1
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• pp.55-61
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• 1993

Soil samples and the intestinal contents of arthropods, mollusca, pisces, aves, and mammals were examined for the presence of Clostridium botulinum. Demonstration of Clostridium botulimun was accomplished by identifying its toxin in liquid cultures inoculated with soil or material from the alimentary tract of tested animals with toxin neutralization tests in addition to morphological, cultural and biochemical tests. Incidences of Clostridium botulinum in tested samples were 5.0% in soil, 6.7% in mammal and 8.7% in fish, respectively. All of the positive cultures were identified as Clostridium botulinum type E and any other type was not demonstrated throughout the survey. Canned foods and solid ham/sausage mixture formulated as can with distilled water were inoculated with Clostridium botulinum type E and checked for toxin production by using the mouse bioassay. Clostridium botulinum type E toxin was produced as a large quantity in canned foods of fish, shell, meat and ham and, however, no significant toxin was detected in sausages and fruit samples.

• Journal of Korea Water Resources Association
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• v.44 no.2
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• pp.145-156
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• 2011

Two dimensional numerical model of high-order accuracy is developed to analyze complex flow including transition flow, discontinuous flow, and wave propagation to dry bed emerging at natural river flow. The bed slope term of two dimensional shallow water equation consisting of integral conservation law is treated efficiently by applying quasi-steady wave propagation scheme. In order to apply Finite Volume Method using Fractional Step Method, MUSCL scheme is applied based on HLL Riemann solver, which is second-order accurate in time and space. The TVD method is applied to prevent numerical oscillations in the second-order accurate scheme. The developed model is verified by comparing observed data of two dimenstional levee breach experiment and dam breach experiment containing structure at lower section of channel. Also effect of the source term is verified by applying to dam breach experiment considering the adverse slope channel.