• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.6
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• pp.591-597
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• 2013

Because most existing non-Newtonian models are not suitable for application to the lattice Boltzmann method, theoretical and numerical studies in this regard remain challenging. In this study, the hydrokinetic (HK) model was modified and applied to a 3D sudden contraction-expansion channel flow, and the characteristics of the HK model flow were evaluated to generate non-trivial predictions in three-dimensional strong shear flows. The HK model is very efficient for application to the lattice Boltzmann method because it utilizes the shear rate and relaxation time. However, the simulation would be unstable in a high shear flow field because the local relaxation time sharply decreases with an increase in the shear rate in a strong shear flow field. In the HK model, it may become necessary to truncate the relaxation time and non-dimensional parameter to obtain stable numerical results.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.373-380
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• 2013

A severe pink mold rot on matured asian pear (Pyrus serotina Rehder) fruit occurred in the organic farmers' orchard in Jinju, Korea in October, 2012. Decay of pear fruit appeared as a softened water-soaked symptom that was easily punctured by pressure. Later pink mycelium appeared on the surface of pear fruit and produced a mass of powdery pink conidia spores. Optimum temperature for mycelial growth of T. roseum was $25^{\circ}C$. Conidia showed hyaline, smooth, 2-celled, thick-walled with truncate bases, ellipsoidal to pyriform, and characteristically held together zig-zag chains and $10{\sim}22(34){\times}6{\sim}10(12){\mu}m$ in size. Conidiophore was erect, colorless, unbranched type, and 4-5 ${\mu}m$ width. On the basis of mycological characteristics, pathogenicity test, and molecular identification with the ITS region, the causal fungus was identified as Trichothecium roseum (Pers.) Link ex Gray.

• Journal of Internet Computing and Services
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• v.23 no.3
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• pp.67-76
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• 2022

Power and signal transmission using electromagnetic waves are essential in modern times, and a guided structure is needed to transmit electromagnetic waves efficiently through the desired path. This paper performed an electromagnetic simulation using the in-house code for the 2-D/3-D waveguide using the finite element method. The accuracy of the analysis was verified by comparing it with the results of HFSS, a representative electromagnetic wave simulation software. In addition, the performance of the Absorbing Boundary Condition (ABC), which is essential to truncate the infinite computational domain for computational electromagnetics, was analyzed. Finally, the parallelization technique was applied to accelerate the simulation speed, demonstrating performance improvement.

• Fisheries and Aquatic Sciences
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• v.25 no.9
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• pp.463-472
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• 2022

In this study, a microbial risk assessment was performed for the bacteria Vibrio parahaemolyticus, which causes a foodborne illness following the consumption of Jeotgal, a fermented seafood in South Korea. The assessment comprised of six stages: product, market, home, consumption, dose-response, and risk. The initial contamination level (IC) was calculated based on the prevalence of V. parahaemolyticus in 90 Jeotgal samples. The kinetic behavior of V. parahaemolyticus was described using predictive models. The data on transportation conditions from manufacturer to market and home were collected through personal communication and from previous studies. Data for the Jeotgal consumption status were obtained, and an appropriate probability distribution was established. The simulation models responding to the scenario were analyzed using the @RISK program. The IC of V. parahaemolyticus was estimated using beta distribution [Beta (1, 91)]. The cell counts during transportation were estimated using Weibull and polynomial models [δ = 1 / (0.0718 - 0.0097 × T + 0.0005 × T²)], while the probability distributions for time and temperature were estimated using Pert, Weibull, Uniform, and LogLogistic distributions. Daily average consumption amounts were assessed using the Pareto distribution [0.60284,1.32,Risk Truncate(0,155)]. The results indicated that the risk of V. parahaemolyticus infection through Jeotgal consumption is low in South Korea.

• Journal of Internet Computing and Services
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• v.24 no.2
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• pp.27-36
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• 2023

Waveguides are transmission lines that guide electromagnetic waves in the desired direction and are utilized in various fields such as medical devices, radar systems, and satellite communications. Computational electromagnetics (CEM) is essential for designing and optimizing waveguides. The finite element method (FEM), which is one of the numerical analysis techniques, is efficient in solving closed problems such as waveguides. In order to apply FEM for waveguide analysis, boundary conditions that truncate the computational domain are required. This paper performs electromagnetic simulations using absorbing boundary conditions (ABC) and waveguide port boundary conditions (WPBC) in 2/D and 3/D waveguides using the finite element method and compared their performances. The accuracy of the analysis was verified by comparing the results with HFSS, a representative commercial electromagnetic simulation software. Simulation results confirm that applying WPBC allows for smaller analysis domains than ABC.

• Research in Plant Disease
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• v.18 no.3
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• pp.250-254
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• 2012

In July 2011, hundreds of garden cosmos (Cosmos bipinnatus) were found to be infected with a white smut in Namyangju. Further surveys in central Korea showed that the disease occurred in all the nine localities visited, with disease incidence rate of >50%. Symptoms manifested as pale-green to chlorotic areas on the leaves, followed by white mildew development on lesions. The lesions usually coalesced and became necrotic, considerably reducing the aesthetic value. Caespituli were initially hypophyllous but later epiphyllous as well. Conidiophores were 10-40 in moderately dense fascicles, hyaline throughout, mostly guttulate, $20-45{\times}2-4{\mu}m$, obtuse at the apex, and had inconspicuous conidial scars. Conidia were solitary, botuliform, hyaline, aseptate, mostly guttulate, apex rounded, base rounded to truncate, $17-24{\times}3.5-5{\mu}m$, hilum inconspicuous, unthickened, and not darkened. Sori were rounded to elongated, resulting in first white and later brown leaf spots. Teliospores embedded in the leaf tissue were subglobose to ellipsoidal, subhyaline to pale yellowish-brown, $12.5-20{\times}10-15{\mu}m$. These morphological characteristics corresponded with those of Entyloma cosmi V$\acute{a}$nky, Horita & Jage. This is the first report of white smut disease of garden cosmos due to infection of E. cosmi in Korea.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.429-433
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• 2014

In 2012, a pink mold rot was observed on apple (Malus pumila var. dulcissima Koidz.) at the Wholesale Market for Agricultural Products, Jinju, Korea. The first symptom of pink mold rot on apple fruit is a water-soaked appearance of the affected tissue and surface fruit formed pink mold rot, then became brown and produced a mass of powdery pink conidia spores. Colony was fast growing colonies, pinksh, zonate in diurnal rhythm, powdery from conidia. Optimum temperature for mycelial growth was $25^{\circ}C$. Conidia were hyaline, smooth, two-celled, thick-walled conidia with truncate bases, ellipsoidal to pyriform, and characteristically held together zig-zag chains and $12-26{\times}8-12{\mu}m$ in size. Conidiophore was erect, colorless, unbranched, and $4-5{\mu}m$ wide. On the basis of mycological characteristics, pathogenicity test, and molecular identification with the ITS region, the causal fungus was identified as Trichothecium roseum (Pers.) Link ex Gray.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.571-575
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• 2014

'Dream Song' is a cultivar of Gypsophila paniculata developed by the Jeollabuk-do Agricultural Research & Extension Services in 2010 for cut-flower production. This hybrid was bred from 121 seedlings collected from an open-pollinated population of 'Gyp06-11'. It has novel morphological characteristics of upright plant type, lanceolate leaves, double florets with a few bright white-colored petals of obovate shape, truncate petal tips, and cup-shaped calyces. Furthermore 'Dream Song' has desirable cultivation characteristics including narrow branching angle, and moderate resistance to powdery mildew, thrips and leaf miners. Moreover it produces more primary branches, and longer internodes and flower stalks than reference cultivar 'Bristol Fairy' during summer cultivation in a subalpine area (500 m over the sea level). Flowering in 'Dream Song' is delayed by about 17 days as compared to 'Bristol Fairy'. 'Dream Song' produces normal flowers with 2 pistils and an average of 10.4 stamens, with fewer malformed flowers than 'Bristol Fairy'.

• The Korean Journal of Applied Statistics
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• v.32 no.5
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• pp.693-702
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• 2019

Deep learning has gained popularity for the classification and prediction task. Neural network layers become deeper as more data becomes available. Saturation is the phenomenon that the gradient of an activation function gets closer to 0 and can happen when the value of weight is too big. Increased importance has been placed on the issue of saturation which limits the ability of weight to learn. To resolve this problem, Glorot and Bengio (Proceedings of the Thirteenth International Conference on Artificial Intelligence and Statistics, 249-256, 2010) claimed that efficient neural network training is possible when data flows variously between layers. They argued that variance over the output of each layer and variance over input of each layer are equal. They proposed a method of initialization that the variance of the output of each layer and the variance of the input should be the same. In this paper, we propose a new method of establishing initialization by adopting truncated normal distribution and truncated cauchy distribution. We decide where to truncate the distribution while adapting the initialization method by Glorot and Bengio (2010). Variances are made over output and input equal that are then accomplished by setting variances equal to the variance of truncated distribution. It manipulates the distribution so that the initial values of weights would not grow so large and with values that simultaneously get close to zero. To compare the performance of our proposed method with existing methods, we conducted experiments on MNIST and CIFAR-10 data using DNN and CNN. Our proposed method outperformed existing methods in terms of accuracy.

• Research in Plant Disease
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• v.19 no.3
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• pp.226-228
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• 2013

In 2012, a pink mold rot was observed on unishiu orange (Citrus unshiu Mac.) fruits at the Wholesale Market for Agricultural Products, Jinju, Korea. The symptom on unishiu orange was a water-soaked lesion on the surface of fruit, which later on enlarged to form softened brown rot lesions. The diseased fruits were covered with pink-colored mold, consisting of conidia and conidiophores of the pathogen. Optimum temperature for mycelial growth was $25^{\circ}C$. Conidia were hyaline, smooth, 2-celled, and thick-walled conidia with truncate bases, ellipsoidal to pyriform, characteristically held together zig-zag chains and $12-26{\times}8-12{\mu}m$ in size. Conidiophore was erect, colorless, unbranched, and 4-5 ${\mu}m$ wide. On the basis of mycological characteristics, pathogenicity test, and molecular analysis with complete ITS rDNA region, the causal fungus was identified as Trichothecium roseum (Pers.) Link ex Gray. This is the first report of pink mold rot caused by T. roseum on unishiu orange in Korea.