• Mycobiology
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• v.35 no.2
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• pp.97-99
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• 2007

Specimens collected from sweet potato plants with slime mold symptoms in fields in Daejeon, Korea were examined. Two species of Myxomycetes, Fuligo septica and Stemonitis herbatica were identified based on their morphological characteristics. This is the first report that the two species of Myxomycetes cause slime mold of sweet potato in Korea.

• Mycobiology
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• v.37 no.3
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• pp.238-239
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• 2009

Recently, a severe slime mold infestation affected oriental melon plants in fields in Chilgok county, Gyeongbuk province, Korea. Specimens were collected from the fields and examined for identification. A species of Myxomycetes, Fuligo gyrosa, was identified based on its morphological characteristics. This is the first report that F. gyrosa causes slime mold of oriental melon.

• Asian Journal of Turfgrass Science
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• v.10 no.3
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• pp.187-194
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• 1996

Dictyostelid cellular slime molds were isolated from soils and harks of the subtropical forest of Torreya nucifera in Cheju island. The results were as follows: Polysphondylium pallidum,Dictyostelium purpureum, D. mucoroides, D. aureo-stipes var. aureo-stipes, D. flavidum, D. miniutum, P.violaceu m, D. monocrhasioides. D. brefeldianum, D. polvcephalum. D. areum var. areum, P. tenuissimum, D. fasciculatum. In this forest, P. pallidum and D. purpureum were occurred dominantly, and D. mucoroides and D. aureo-stipes var, aureo-stipes were the second dominant. It was distinguished that D. purpureum was much more cornmonly found than the other forests. Cellular slime molds from the barks of the tree heights of 1,3 and 5m were occured 7, 3 and 2 species respectively. Torreya fruit extract affected on the growth of D. aureo-stipes var. aureo-stipes and D. flavidum but not on D. purpureum and D. mucoroides. Key words: Cellular slime mold, Torreya forest, Torreya fruit extract.

• Asian Journal of Turfgrass Science
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• v.10 no.3
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• pp.247-262
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• 1996

In this study, the distribution of dictyostelid cellular slime molds was investigated from F, H and $A_1$ horizon of pinus, oak forests in Mt. Puk'an, Mt. Nam and Mt. Kwanak. The relationship of cellular slime molds with other soil microorganisms and abiotic factors were analyzed. The six species were isolated as follows: Polysphondlium pallidurn, Dictyostelium purpureum, D. mucoroides, D. crassicaule, D. capitatum, D. implicatum. The dominant species in pinus forests was P. pallidum, and in oak forests it was D. macro ides. In Mt. Nam, D. mucoroides and P. pallidum were isolated at only oak forest. The Correlations of slime mold abundance with bacteria were significant. Even though positive correlations of cellular slime molds with actinomycetes or fungi were not significant, correlations between soil microorganisms were analyzed. Correlation coefficients were high in Mt. Kwanak(r=0.5921) and Mt. Nam(r=0.7243) at significant level P<0.01. There were significant correlations between total slime molds and abiotic factors. It supports that cellular slime molds are limited by foods in nature. In low level of pH, water content and organic matter, that community diversity is more affected by bacteria whose organic degradation capacity is regulated by interactions of soil microorgaisms. Key words: Cellular slime molds, Soil microorganisms, Correlations, Abiotic factors.

• Asian Journal of Turfgrass Science
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• v.11 no.2
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• pp.125-137
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• 1997

Five dictyostelid cellular slime molds were isolated from the littoral grassland ecoystems of the lake Paldangho, safeguard of waterworks, Kyounggi-do, South Korea. They were Poiysphoadylium violceum, Dictyosielium aureo-stipes var. aureo-stipes D crassicaule, D macrocephalum and D gigauteum. P. violaceum was dominant species. It live on the low nutrient and barren soils as the littoral zone destabilized in surface soils, litters and chemicals by inundation an rain precipitation. Key words: Cellular slime mold, Littoral grassland ecosystem.

• The Korean Journal of Mycology
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• v.44 no.4
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• pp.342-345
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• 2016

Chaenomeles sinensis, called as Chinese quince, belongs to the family Rosaceae and is widely distributed in Korea, China, and Japan. A microorganism was isolated from part of a twig of C. sinensis that showed an abnormal appearance. The microorganism was identified as the slime mold Stemonaria longa of the division Myxomycota, which was previously unrecorded in Korea. The present study reports the morphological characteristics of the isolated fungus and a phylogenetic relationship based on the ${\beta}$-tubulin gene sequences.

• ETRI Journal
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• v.46 no.3
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• pp.461-472
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• 2024

We propose a network traffic prediction model based on linear and nonlinear model combination. Network traffic is modeled by an autoregressive moving average model, and the error between the measured and predicted network traffic values is obtained. Then, an echo state network is used to fit the prediction error with nonlinear components. In addition, an improved slime mold algorithm is proposed for reservoir parameter optimization of the echo state network, further improving the regression performance. The predictions of the linear (autoregressive moving average) and nonlinear (echo state network) models are added to obtain the final prediction. Compared with other prediction models, test results on two network traffic datasets from mobile and fixed networks show that the proposed prediction model has a smaller error and difference measures. In addition, the coefficient of determination and index of agreement is close to 1, indicating a better data fitting performance. Although the proposed prediction model has a slight increase in time complexity for training and prediction compared with some models, it shows practical applicability.

• The Korean Journal of Ecology
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• v.23 no.4
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• pp.315-321
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• 2000

The occurrence and distribution of Dictyostelid cellular slime molds on Mt. Mukak soils with two different vegetation types were investigated. Two plating methods were used for the isolation of dictyostelids following Dr. Hagiwara's method. Dictyostelium and Polysphondylium were isolated in these soils. D. purpureum (subtropical form ) and D. giganteum were observed in both Quercus variabilis and Pinus thunbergii communities soils. D. delicatum, B. sp-1 (D. brefeldianum complex). D. sp-2 (D. brefeldianum complex), D. minutum and P. pallidum complex occurred only in Q. variabilis soil. D. macrocephalum, D. purpureum (temperate form ), D. robustum, D. polycephalum, P. violaceum, and P. pallidium occurred only in P. thunbergii soil. P. pallidium complex is being identified.

• Smart Structures and Systems
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• v.33 no.1
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• pp.65-91
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• 2024

The use of five optimization techniques for the prediction of a strength-based concrete mixture's best-fit model is examined in this work. Five optimization techniques are utilized for this purpose: Slime Mold Algorithm (SMA), Black Hole Algorithm (BHA), Multi-Verse Optimizer (MVO), Vortex Search (VS), and Whale Optimization Algorithm (WOA). MATLAB employs a hybrid learning strategy to train an artificial neural network that combines least square estimation with backpropagation. Thus, 72 samples are utilized as training datasets and 31 as testing datasets, totaling 103. The multi-layer perceptron (MLP) is used to analyze all data, and results are verified by comparison. For training datasets in the best-fit models of SMA-MLP, BHA-MLP, MVO-MLP, VS-MLP, and WOA-MLP, the statistical indices of coefficient of determination (R²) in training phase are 0.9603, 0.9679, 0.9827, 0.9841 and 0.9770, and in testing phase are 0.9567, 0.9552, 0.9594, 0.9888 and 0.9695 respectively. In addition, the best-fit structures for training for SMA, BHA, MVO, VS, and WOA (all combined with multilayer perceptron, MLP) are achieved when the term population size was modified to 450, 500, 250, 150, and 500, respectively. Among all the suggested options, VS could offer a stronger prediction network for training MLP.

• Mycobiology
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• v.36 no.3
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• pp.143-147
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• 2008

We have detected the slime mold, Diachea leucopodia (GNU06-10) in a strawberry greenhouse located in Sancheong-gun, Gyeongnam. Typical fruiting bodies had developed gregariously on the strawberry leaves, petioles, and plant debris on ground soil habitat, and also surprisingly on plastic pipes and a vinyl covering. Field samples were examined via stereomicroscopy, light microscopy, and SEM for the determination of morphological characteristics. Dark-brown to black spores formed gregariously within the stipitate cylindrical sporangium, and were covered by an iridescent peridium, which may be intact at maturity, or may have disintegrated. The upper portion of the peridium generally breaks up to expose the spores, whereas the lower portion was usually persistent. The results of energy dispersive X-ray spectrometer (EDS) analysis showed that lime was present in the stalk and columella but absent from the spores, capillitium, and peridium. The above characteristics confirm its taxonomic position in the genus Diachea. However, this genus is intermediate in character between the Physarales and Stemonitales of the Myxogastromycetidae. Hence, this genus had been classified as a member of the Stemonitales until the mid-1970's, on the basis of its iridescent peridium and noncalcareous capillitial system, similar to Comatricha of the Stemonitaceae. By way of contrast, emphasis on morphological characteristics, most notably the calcareous stalk and typical columella, places Diachea within the order Physarales. The presence of a phaneroplasmodium during the trophic stage and lime deposition in its sporophores, as was confirmed in this work, supported the inclusion of Diachea in the Physarales, and the noncalcareous capillitial system verified its identification as a member of the Didymiaceae. Further characteristics of the species D. leucopodia include the following: phaneroplasmodium, spore globose 7.5 ${\mu}m$ in diameter, very minutely roughened; sporangia $500{\mu}m\times1mm$, more or less cylindrical, gregarious, stalked 1.2mm; stalk and columella white.