• Journal of Korea Multimedia Society
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• v.12 no.11
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• pp.1593-1608
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• 2009

If a certain relay node in multi-hop wireless networks might become a malicious node that does not cooperate with other nodes or a selfish node, network throughput will be dramatically decreased. Most of existing ad hoc routing protocols assuming that the nodes will fully cooperate with other nodes do not resolve the problem of network performance degradation due to malicious and selfish nodes. This paper presents the CARE (Cooperative Ad hoc routing protocol based REputation) scheme incorporating the reputation management that can achieve a multi-hop wireless network with high throughput performance. The proposed scheme provides the horizontal cross-layer approach which can identify misbehaving malicious, selfish nodes dropped out of the hop-by-hop based packet processing in the network and then set up an optimal packet routing path that will detour misbehaving nodes. And the vertical cross-layer approach contained in the CARE scheme attempts to improve the quality of routing paths by exploiting the quality of link information received from the MAC layer. Besides, it provides high TCP throughput by exploiting the reputation values of nodes acquired from the network layer into the transport layer. A case study on experiments and simulations shows that the CARE scheme incorporating vertical and horizontal cross-layer approaches yields better performance in terms of the low rate of packet loss, fast average packet delivery time, and high TCP throughput between end-to-end nodes.

• Korean Journal of Ecology and Environment
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• v.54 no.3
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• pp.156-169
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• 2021

Traditional morphological identification difficulties, such as phenotypic plasticity, misidentification of cryptic species, and larval stage species, can be compensated for by using DNA analysis techniques, such as DNA barcoding, in surveying zooplankton populations, including species identification. Recently, the rapid development of DNA sequencing techniques has allowed DNA-based community analysis not only for zooplankton assemblages in various aquatic ecosystems but also for the gut contents of zooplankton that are limited by conventional methods such as visual and microscopic identification. Therefore, the application of DNA sequencing can help understand biological interactions through the analysis of zooplankton food sources. The present paper introduces the major DNA-based approaches in zooplankton research topics, including taxonomic approaches by DNA barcoding, community-level approaches by metabarcoding, and gut content analyses, summarizes the analysis methods, and finally suggests the methodological topics that need to be considered for future applications.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.2
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• pp.130-137
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• 2021

This study evaluated newly introduced, commercial super sweet corn hybrids (Zea mays L.) for their potential as breeding materials. Agronomic traits were measured and variance components were obtained using a linear mixed model to estimate the heritability. The trials were carried out in 2018 at two locations (Haenam and Oksan in South Korea). All traits had low heritability, except for mid tasseling and silking days. These traits with low heritability mostly had low genetic variance component estimate. In case of ear height ratio, significant genotype by location appeared to be responsible for low genetic variance, which in turn led to low heritability. Low heritability estimates from the trials with commercial hybrids were perhaps because those hybrids were highly improved for commercial success. Hence, this does not necessarily point to them having poor potential as breeding materials. To overcome low heritability, significant genotype by environment interaction, and achieve high selection efficiency, intermating among hybrids is recommended to create new recombinants before inbred line development.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.215-222
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• 1996

This study was conducted to compare the growth and yield, and to determine the optimum planting date and density in two improved black soybean varieties. The two varieties were planted by driller attached a tractor on May 21 and June 19, 1993, and treated five planting densities, respectively. Yield of Gumjeongkong 1 was similer for both planting dates, but that of Suwon 157 was remarkably reduced on June 19 planting compared to May 21. There was significant differences between planting dates in stem length, number of branches, seeds per plant, seed weight and yield. Planting density, also, significantly affected on stem length, number of branches and seeds per plant. Statistically significant interactions between planting date$\times$variety and planting date$\times$planting density were found at almost all characteristics, except between variety$\times$planting density. Optimum planting date and density of Gumjeongkong 1 for high yield were June 19 and 33, 000 plants per l0a, and those of Suwon 157 were May 21 and 22, 000 plants per l0a, respectively. The coefficient of variation at different planting densities was high at stem length, number of branches, seeds per plant and yield, but low at number of main stem node, seeds per pod and 100 seed weight.

• Journal of Practical Agriculture & Fisheries Research
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• v.4 no.1
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• pp.70-79
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• 2002

This study was conducted to determine correlations and combining abilities of leaf lengths, leaf widths, petiole lengths, number of branches, number of leaves, leaf areas, fresh weights, dry weights and number of flowers in F₁ crosses made with the partial seven-parent diallel cross in Viola tricolor. Leaf lengths and leaf widths showed highly positive correlation with petiole length and negative correlation with number of branches, number of leaves and number of flowers. There was positive correlation between the number of leaves and flowers as well as between leaf area and fresh weight. Mean squares of general combining ability(GCA) and specific combining ability(SCA) were highly significant for all the parameters. Variance component values of SCA were greater than those of GCA for all the parameters except leaf length, implying preponderance of non-additive gene actions for these characters. The lines C and G for leaf lengths and widths, the lines A and F for number of leaves, the lines A, B and G for leaf areas, and the lines B and F for number of flowers showed relatively high GCA effects. The crosses of A×B and B×D exhibited high SCA effects on increasing leaf lengths, leaf widths, number of leaves, fresh weights and number of flowers. And also the crosses of B×E and D×G exhibited high SCA effects on decreasing leaf lengths, leaf areas and fresh weights as well as increasing number of flowers. The broad sense heritabilities of most characters were high compared with the narrow sense one. Those of leaf length, leaf width, petiole length and number of leaves were high in both the broad and narrow sense heritabilities.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.4
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• pp.290-295
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• 1989

An incubation study was conducted to examine the effect of soil pH and temperature on nitrification potential of 8 different soil series applied with no-N and 200 ugN/g soil as a compound fertilizer at 60 % moisture content of maximum water holding capacity for 8 weeks, whose series were ranged from acid to mild alkali as Gopyeong(Jincheon, pH 4.51), Yesan(Jincheon, pH 4.54), Jigog(Eumseong, pH 4.71), Songsan(Goesan, pH 5.01), Angye(Seongju, pH 5.34), Banho(Seongju, pH 5.73), Weongog(Jincheon, pH 5.93), and Banho(Seongju, pH 7.70), respectively. Interrelationship between the nitrifiable and the net $NO_3-N$(N added plot-no-N plot) accumulated in the soil and tobacco yield in the no fertilizer plot were investigated as well. 1. Nitrification response was various according to soil characteristics at each temperature condition showing that nitrifiable $NO_3-N$ values of the soils were much higher at $25^{\circ}C$ than $15^{\circ}C$. And difference of nitrification potential affected by temperature was markedly distinguishable from 2 weeks after incubation and was showing a tendency to reduce with increasing of soil pH. 2. At each temperature condition, net $NO_3-N$ accumulated at 2 and 4 weeks after incubation was positively correlated with soil pH. 3. Tobacco yield in the no fertilizer plot was more highly correlated with the values of nitrifiable and net $NO_3-N$ accumulated at $15^{\circ}C$ similar to soil temperature in rhizosphere of early stage of tobacco growth than those at optimum temperature($25^{\circ}C$).

• Journal of Engineering Education Research
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• v.3 no.1
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• pp.3-11
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• 2000

HALS (Hypermidia Aided Learning System) is very useful computer networking educational system in knowledge-driven society, and has been developed by Kyungwon University. This system has three characteristics; 1) face-to-face learning, 2) ultra high-speed information networking, 3) web-based hypermedia courseware. So, the purpose of this paper is to introduce the application to engineering educational program (electrical engineering: electric power system, control system). For this purpose it is described the definition and characteristics of HALS. Next, it is represented the model of electrical engineering educational program applied to HALS and the developed courseware.

• The Korean Journal of Zoology
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• v.31 no.1
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• pp.29-34
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• 1988

In order to investigate the role of nuclei and cytoplasm in early embryogenesis, interspecific nuclear transplantation was carried out Nuclei of one species of amphibian was transplanted into enucleated egg of another species. In interspecific hybrids between Rana species, development was arrested before or right after the dorsal lip formation. In intergenetic hybrids between Rana, Xenopus and axolod, developmental arrest took place at late blastula stage. Comparing the developmental capacity of each nudeocytoplasmic hybrid, the more distantly related the species, the earlier does development arrest. The general rule is that nuclear transfers between any amphibian species will form a regulary cleaved late blastula. Two plausible factors relate to limitation of tite developmental capacity of nudeocytaplasmic hybrids. One is an irreversible change in grafted nuclei and another is tunctional incompatibility between the recipient cytoplasm and transplanted nucleus. The later is postulated a more possible cause of the arrestrnent.

• Korean Journal of Plant Resources
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• v.12 no.3
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• pp.198-203
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• 1999

7S and 11S globulins are two major storage proteins in soybean seed. For improving the quality of soybean seed protein, an increase of 11S/7S ratio would be a desirable objective because 11S globulin contains much more sulfur-containing amino acids than 7S globulin. In this study, six soybean varieties grown at three locations were used for genetic variation analysis of 7S and 11S globulins. It was possible to screen the soybean genotypes having aberrant subunit compositions of the two globulins by a sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). So, heritabilities, genotypic and phenotypic correlations among eight globulin fraction contents of soybean seeds were estimated. The mean value of 7S and 11S globulin fraction contents were 38.9% and 61.1%, respectively, and the ratio of 7S to 11S globulin ranged from 0.58 to 0.74. The high heritability value was found in $\beta$ subunits but the values of acidic and basic subunits were relatively low. Genotypic correlations were higher than the corresponding phenotypic correlations in most of globulin subunit contents. $\beta$ subunits was negatively correlated with $\alpha$ and $\alpha$' subunits among 7S fractions, while no significant correlation between $\alpha$ and $\alpha$' subunits could be found In case of 11S fractions, acidic and basic subunits exhibited no genotypic but negative phenotypic correlation.

• Journal of Life Science
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• v.22 no.7
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• pp.950-957
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• 2012

Development of garlic processing products by thermal treatment and researched biological activity of a new product, red garlic. Red garlic MeOH extract was graduated by solvents, such as hexane, chloroform, ethyl acetate, butanol, and water, in order. Each solvent fraction was dried by a rotary evaporator and then resolved in water for analysis of its antioxidant and antiobesity activity. Browning compounds of red garlic fractions were the highest in the chloroform fraction. Total phenolic compounds and flavonoid content were highest in the hexane fraction. The chloroform fraction showed significantly higher activity in DPPH, ABTS radical scavenging activity, and antioxidant activity by FRAP. We propose that the antioxidant activity of the solvent fractions from red garlic was revealed interaction of browning compounds, total phenolic compounds, and flavonoids. Due to the higher activity of the shown fraction, the hexane and the chloroform fractions were have high contents of these compounds. Below $500{\mu}g/ml$, pancreatic lipase inhibition activity was significantly increased by sample concentration. And chloroform fraction, have the highest inhibition activity was shown over the 40%. In 3T3-L1 cells, the lipid accumulation inhibition activity was lower in the hexane and in the chloroform fraction than in the other fractions.