• Korean Journal of Plant Tissue Culture
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• v.26 no.2
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• pp.115-119
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• 1999

The single node cuttings of sweet potato (cv. Mokpo #29) plantlets maintained in vitro were cultured with (MF+) or without membrane filter (MF-) under photomixotrophic (PM), hetrotrophic (HT) and autotrophic (AT) conditions. Shoot length was the greatest (11.9cm) in 3$0^{\circ}C$ (HT) treatment and it was the shortest (3.4 cm) in $25^{\circ}C$ (PM) treatment. Nodal explants cultured in 3$0^{\circ}C$ treatment looked more vigorous than those of $25^{\circ}C$ in appearance, and node number was the greatest (10.5 per plantlet) among the treatments. But plantlets grew in 3$0^{\circ}C$ (HT) treatment were observed all overgrown. The size in leaf area was about 2 times greater and shoot length was about 2 times shorter in PM than in HT condition. Percent dry matter of shoots was 5.9% (HT) and 7.4% (PM) in $25^{\circ}C$ treatment and 6.1% (HT) and 7.4% (PM) in 3$0^{\circ}C$ treatment. Plantlets cultured in the MF+ treatments were less succulent than those cultured in the MF- treatment. Vitrified plantlets were examinated 14.8% (both $25^{\circ}C$ and 3$0^{\circ}C$) in PM condition and 22.2% ($25^{\circ}C$) and 31.5% (3$0^{\circ}C$) in HT condition. Sucrose was necessary for the survival of in vitro plantlets. In the sucrose-free medium, explants cultured in the MF- had turned yellow and were dead after 30 days of culture. But explants cultured in the MF+ were alive and produced plantlets with shoot and root (AT). On the other hand, the survival of explants on the MS basal medium (sucrose-free and hormone-free) depended entirely upon the MF attachment.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.879-884
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• 2002

Cold and hot water fractions of Diospyros kaki were screened to determine its anti-complementary activity. Flour of Diospyros kaki leaf (250 g) was boiled at $100^{\circ}C$ for 3 h and passed through a membrane of 10 kDa molecular weight (DK-0). DK-0 was precipitated with ethanol and refluxed with methanol to obtain the crude polysaccharide (DKC). DKC-1 was isolated by ion exchange chromatography on DEAE-Toyopearl 650C, and DKC-1c was purified from DKC-1 by size exclusion chromatography on Bio gel P-60. The anti-complementary activities of DKC-1c at $1000\;{\mu}g/mL$ were 85.4 and 61.1% via whole and alternative pathways, respectively. DKC-1c was determined as a neutral polysaccharide composed of glucose (29.0 mol.%), arabinose (24.3 mol.%), and galactose (16.2 mol.%) with the molecular weight of 66.6 kDa. Results of agarose gel immunoelectrophoresis revealed DKC-1c, as a complement activator, cleaved C3 into C3a and C3b via both pathways.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.1
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• pp.7-11
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• 2010

The reduction of optical losses in mono-crystalline silicon solar cell by surface texturing is a critical step to improve the overall cell efficiency. In this study, we have changed the sub-micrometer structure on the micrometer pyramidal structure by 2-step texturing. The Ag particles were coated on the micrometer pyramid surface in $AgNO_3$ solution, and then the etching with hydrogen fluoride and hydrogen peroxide created even smaller nano-pyramids in these pyramids. As a result, we observed that the changes of size and thickness of nano structure on pyramidal surface were determined by $AgNO_3$ concentration and etching time. Using 2-step texturing, the surface of wafers is etched to resemble the rough surface of a lotus leaf. Lotus surface can reduce average reflectance from 10% to below 3%. This reflectance is less than conventional textured wafer including anti-reflection coating.

• Korean journal of applied entomology
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• v.46 no.2
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• pp.269-274
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• 2007

This study was performed to estimate the efficacy of three commercial mating disruptors for the control of oriental fruit moth, Grapholita molesta (Busck), using a food-baited trap to collect field females. Mated female ratios estimated in the mating disruptor-treated areas were compared with the estimates of male trap captures, and both estimates were evaluated on the basis of crop damage measured by shoot tip damage caused by G. molesta. Both males and females were attracted to the food trap-baited with terpinyl acetate in apple orchard. Spermatophore of G. molesta was similar to female bursa copulatrix in size. Though there was more than 95% reduction in male trap captures indicating significant mating disruption, significant crop damage occurred on apple leaf buds, in which more than 35% of captured females were mated. This study demonstrates that assessment of the mated females would be more reasonable to represent the efficacy of mating disruptor(s) than the assessment of the male captures in G. molesta.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.421-426
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• 2017

These experiments were conducted to investigate the morphological characteristics, occurrence ecology, host preference, and oviposition of Locusta migratoria to create a forecasting manual in preparation for outbreaks of this species. The sex ratio (female:male) of 274 adult of L. migratoria which occurred naturally in the Muan region of Jeollanam-do was 18.2 : 81.8, 60.9% individuals were of the green type and 39.1% were of the brown type. Body length and body weight were 6.5 cm and 2.8 g for females and 5.0 cm and 1.5 g for males, respectively; body size did not differ between differently colored individuals. Spawning activity in the field was observed from late August to late October. Eggs laid between late September and early October hatched in late May the following year. Female adults fed 3.5 g of corn leaf and male adult was 1.6 g for a day. The host preference of L. migratoria was in the order corn > foxtail millet > millet > silver grass > rice, and preference for silver grass and rice was very low. Pure sand was most favorable for the spawning of L. migratoria, and the cumulative amount of hatching was higher when the soil moisture content was higher after spawning began.

• Spatial Information Research
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• v.19 no.2
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• pp.47-56
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• 2011

Typical tree-based spatial index structures are divided into a data-partitioning index structure such as R-Tree and a space-partitioning index structure such as KD-Tree. In recent years, researches on hybrid index structures combining advantages of these index structures have been performed extensively. However, because the split boundary extension of the node to which a new spatial object is inserted may extend split boundaries of other neighbor nodes in existing researches, overlaps between nodes are increased and the query processing cost is raised. In this paper, we propose a hybrid index structure, called SQR-Tree that can support efficient processing of spatial queries to solve these problems. SQR-Tree is a combination of SQ-Tree(Spatial Quad- Tree) which is an extended Quad-Tree to process non-size spatial objects and R-Tree which actually stores spatial objects associated with each leaf node of SQ-Tree. Because each SQR-Tree node has an MBR containing sub-nodes, the split boundary of a node will be extended independently and overlaps between nodes can be reduced. In addition, a spatial object is inserted into R-Tree in each split data space and SQ-Tree is used to identify each split data space. Since only R-Trees of SQR-Tree in the query area are accessed to process a spatial query, query processing cost can be reduced. Finally, we proved superiority of SQR-Tree through experiments.

• Journal of Plant Biology
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• v.5 no.3
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• pp.5-10
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• 1962

Studies on the anatomical observation of Bamboos distributed in East-South Asia for systematic botany were scarecely reported except for the morphological studies on Bamboos, which was investigated by Dr. Hiroshi Usui, present author and others. Recently it has been certain that it could be hardly classify some species of bamboo family without this work. For this reason the author reported the anatomical studies on Korean bamboos in 1959, and furthermore the author intended to identify the two species of Pleioblastum Simoni Nakai in Korean bamboos by studying the characteristics of internal structure and qualitative assay of free amino acid containg in Pleioblastus Simoni Nakai(1), (2). In view of fact that there is some differences between two species, it is likely to be identifiable completely different species one another. Furthermore, a lot of characteristics surveyed by the author were as follow: It was reassumed that two species cultivated under same conditions for three years were different alternately in the species of Pleioblastus Simoni Nakai. At the same time, these studies could clarify some evolutional processes of bamboo family. On the other hand, it was found that two species had not only the obvious difference in aerenchyma, the size of thickwalled parenchyma and bulliform cell, but also the internode of Pleioblastus Simoni Nakai(1) is longer than the other, the speed of growing is more rapid, the leaf of former is narrow and that of latter is wide. The free amino acids containg in each species were found as 18 kinds, especially Pleioblastus Simoni Nakai (2) had not Histidine in spite of containg in Pleioblastus Simoni Nakia(1). From the characteristics and the experiments described above, it seemed to the author that Pleioblasus Simoni Nakai (1) which was growing at the region of Ulsan in Korea.

• Food Science and Preservation
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• v.23 no.7
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• pp.939-944
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• 2016

The aim of this study was to establish an optimum blanching condition for outer cabbage leaves to increase utilization of the byproduct. Outer leaves of Kimchi cabbages were cut to size ($4{\times}4cm$) and blanched at 80, 90, $100^{\circ}C$ for 1, 3, and 5 min. Subsequently, weight loss, pH, total bacteria, coliform and texture properties were investigated. Sensory evaluation of a ready-to-cook soup prepared from blanched outer leaves was investigated to determine whether the quality of the blanched outer leaves was acceptable. Both weight loss and pH of outer leaves of Kimchi cabbage were increased by blanching. Compared to raw samples, total bacterial counts decreased and coliform bacteria were not detected. The hardness of raw leaf samples was $1.5kg{\cdot}force$ (N). Sample hardness was 18.7~21.7% lower after blanching for 3 min and 34.8~36.7% after blanching for 5 min. Sensory evaluation of outer leaves blanched at $100^{\circ}C$ for 5 min revealed significant differences from the other treatments (p<0.05). In addition, sensory evaluation scores for texture and appearance of outer leaves blanched at $100^{\circ}C$ for 3 min were higher than those for commercially available products. The results of this study indicate that blanching can be effective for developing a food product from the outer leaves of Kimchi cabbage.

• Korean Journal of Plant Resources
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• v.24 no.4
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• pp.370-378
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• 2011

To address infra-specific relationships of Sedum kamtschaticum Fisch., and to provide the fundamental information for developing new horticultural variations, we analyzed the morphology of individuals in four natural populations (Mt. Gwangdeok, Mt. Samyeong, Mt. Yonghwa, Tongyeong) and investigated the vegetations of these area. Based on 50 morphological characters the principle component analysis (PCA) has been performed. Principle component axis 1, 2, and 3 explain 22.9%, 14.2%, and 7.4% of total variations, respectively. Dot plot of OTUs in PC2 by PC1 area showed that the areas of four populations are completely overlapped. The result of PCA and the statistics of each character indicate that all of morphological characters are overlapped in these four populations. The maximum deviations are found in the characters related in the size and shape of the leaf. In the vegetation analyses, eighteen community plots that we investigated were grouped into 10 subcommunities: subcomm. Boehmeria spicata, subcomm. Artemisia stolonifera, subcomm. Artemisia keiskeana, subcomm. Impatiens nolitangere, subcomm. Crepidiastrum chelidoniifolium, subcomm. Urtica thunbergiana, subcomm. Artemisia gmelini, subcomm. Commelina communis, subcomm. Erigeron annuus-Artemisia princeps, and typical subcommunity.

• Korean Journal of Plant Taxonomy
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• v.48 no.3
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• pp.163-171
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• 2018

In Korea, Hypodematium glanduloso-pilosum was formerly known as the only Korean native species in the genus. Recently, however, we reported one unrecorded taxon, H. squamuloso-pilosum Ching, which was found on rocks at a limestone mountain in Yeongwol, along with one new taxon, H. angustifolium in Okcheon. Traditionally, Hypodematium taxa are often distinguished from each other by vegetative characters such as pinnatifid lamina, glandular hairs, and narrower or linear lanceolate scales on stipe bases. H. glanduloso-pilosum, distributed widely throughout the country except on Jejudo Island in Korea, exhibiting variations in leaf segregation, indusia positions, hair distributions and size. The high variation in the morphological characters in the widely distributed taxon has caused problems delimitating three native species from each other. To evaluate the phylogenetic relationships among H. glanduloso-pilosum and taxa related to Hypodematium (all Korean native taxa), we carried out morphological and molecular analyses (cpDNA rbcL and psbA-trnH) of populations of the genus Hypodematium in Korea. Although H. glanduloso-pilosum exhibits high variations in some morphological characters, the species is characterized by stipes and indusia with densely multicellular hairs and rod-shaped glandular hairs or hairs and lanceolate or oblong lanceolate scales in rhizomes and stipe bases distinguished from those of other Korean native taxa (H. squamuloso-pilosum and H. angustifolium). In the analyses of cpDNA data, three Korean native taxa are placed in the same clade, i.e., in the glanduloso-pilosum group. Moreover, our analyses propose that H. squamuloso-pilosum (China and Korea), H. angustifolium (Korea), and H. fordii (China and Japan) share the same glanduloso-pilosum clade with H. glandulosopilosum (China, Korea, and Japan).