• Asian-Australasian Journal of Animal Sciences
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• v.4 no.3
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• pp.245-250
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• 1991

Analysis of the characteristics and the grouping of the species of sown and weeds in artificial pastures was studied applying the principal component analysis method. Presency and coverage of six sown species and fifteen weed species which occurred in pastures of under-grazing and optimumgrazing were subject to analysis. From field survey, species were divided into three groups: the group A included five species such as Festuca arundinacea, Lolium perenne and Dactylis glomerata, etc., the group B included eleven species such as Polygonum longisetum, Agrostis alba and Rumex obtusifolius, etc., and the group C included five species such as Miscanthus sinensis, Rubus palmatus and Artemisia princeps, etc. The group A species corresponded to good pasture conditions and management. On the contrary, the group C species occurred in poor pasture conditions with inadequate management. The group B species corresponded to intermediate pasture conditions and management. Interrelated pair species co-existing and species non-co-existing were discovered. Factor loading as negative for the group A species. positive for the group C species and positive but lower than the group C species for the group B species. From these results it is concluded that the principal component analysis seems to one of the useful tools for the analysis of characteristics of species and the diagnosis of sown pasture vegetation, although further studies are required to get more general information about species characteristics.

• Korean Journal of Environmental Biology
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• v.36 no.3
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• pp.370-376
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• 2018

It is important to consider interaction between species in understanding structure and function of the biological community. Current ecological issues such as climate change and habitat loss emphasize the significance of the concept of species interaction in that varying species' interaction across environmental gradients may lead to altered ecological function and services. However, most community studies have focused on species diversity through analysis of quantitative indices based on species composition and abundance data without considering species interactions in the community. 'Ecological network analysis' based on network theory enables exploration of structural and functional properties of ecosystems composed of various species and their interactions. In this paper, network analysis of Cheonggye stream as a case study was presented to promote uses of network analysis on ecological studies in Korea. Cheonggye stream has a simple biological structure with link density of 1.48, connectance 0.07, generality 4.43, and vulnerability 1.94. The ecological network analysis can be used to provide ecological interpretations of domestic long-term monitoring data and can contribute to conserving and managing species diversity in ecosystems.

• Korean Journal of Environment and Ecology
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• v.29 no.2
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• pp.221-227
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• 2015

This study was carried out to measure seasonal changes in the community structure and species composition of marobenthos in the intertidal area of Dokdo. The macrobenthos identified during this study was comprised of 36 species: predominately 25 species of mollusks(69.4 %), 6 species of arthropods(16.7 %), 3 species of echinodermata(8.3 %) and 1 species of cnidaria (5.6 %). The number of marobenthos species ranged from 27 in Spring to 33 in Autumn. In terms of the top 10 dominant species, there were 7 species of mollusks and 3 species of arthropods in the this study. After analyzing the bray-curtis similarity, it was divided into two large groups(A, B). Such group classification matched the SIMPROF(Similarity Profile Analysis) and the one-way ANOSIM(Analysis of similarities) analysis.

• Ocean and Polar Research
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• v.42 no.2
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• pp.157-169
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• 2020

This study aimed to analyze the effect of total allowable catches (TACs) on the target species. First to effects analyse of TACs, the 8 TAC target species and 75 non-target species were selected for which catch data were available before and after the introduction of the TACs. The 8 target species were simply compared to catch changes before and after TACs. Through the comparison, it was confirmed how the catches of target fishes have changed after the implementation of the TACs. Secondly, the Difference In Differences(DID) analysis was conducted to confirm the effects of the TACs on the catches of the target fishes using the catch data of 8 TAC target species and 75 non-TAC species. Finally, to overcome the limitations of the DID analysis, the random effects model was estimated to confirm the effects of the TACs on the catch of the TAC target species. Overall, this study confirmed that the TACs affects catches of target species, not only through simple comparisons of catches before and after the introduction of the TACs but also through econometric analysis.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.12
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• pp.3372-3381
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• 1995

An equilibrium analysis was carried out to determine principal species of heavy metals in waste incineration and their behaviors with variation of temperature, chlorine concentration, excess air ratio, and C/H ratio. The waste was assumed as a compound of hydrocarbon fuel, chlorine, and metals. Calculated results showed that the most important parameter to determine the principal species was temperature. Chlorine concentration also affected on mole fractions of the principal species. Generally principal species at high temperature were chlorides while there were some metals of which principal species were oxides. At low temperature mole fractions of the principal species increased, but at high temperature mole fractions of some metal species decreased. C/H ratio of the hydrocarbon fuel and excess air ratio had little effect on mole fractions of the metal species, compared to the temperature and chlorine concentration.

• Journal of the Korean Society of Combustion
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• v.1 no.1
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• pp.31-39
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• 1996

An equilibrium analysis was carried out to determine principal species in the incineration of hazardous waste, which was assumed as a compound of hydrocarbon fuel, chlorine, sulfur, and heavy metals, and their behaviors with variation of temperature, chlorine and sulfur concentrations. Calculated results showed that the most important parameter influencing the principal species was temperature. Chlorine concentration affected on mole fractions of the species, especially at high temperature. Existence of sulfur had a significant effect on the species at low temperature, regardless of surfur concentration. Generally, principal species at high temperature were chlorides and oxides, while the principal species at low temperature were sulfides. As temperature increased, mole fractions of the principal species increased at low temperature, however, mole fractions of some metal species decreased at high temperature.

• The Journal of Fisheries Business Administration
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• v.44 no.1
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• pp.71-79
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• 2013

This study is aimed to estimate market integration of wild caught fish species on the Korean market, using both multivariate and bivariate cointegration analysis. For the analysis of market integration between wild caught fish species, major four fish species those are most popular fish in the market and caught by the large purse seine fishery-chub mackerel, jack mackerel, hairtail and spanish mackerel-were selected as analytical target fish species. And their real monthly price data from January 2000 to December 2011 were used in the analysis. The results of the multivariate cointegration test for four wild caught fish species showed that there would be long-term equilibrium relationships among prices of four wild caught fish species, and consequently, the markets for wild caught fish species were estimated to be integrated. The results of exclusion test and bivariate cointegration test also supported that there would be a clear evidence to suggest that all target wild caught fish species were cointegrated each other.

• Animal cells and systems
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• v.16 no.6
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• pp.488-497
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• 2012

A DNA barcode based on 648 bp of cytochrome c oxidase I (COI) gene aims to build species-specific libraries for animal groups. However, it is hard to recover full-length (648 bp) barcode gene from environmental fecal samples due to DNA degradation. In this study, we designed a new primer set (K_Bird), which amplifies a 226 bp fragment targeted an inner position of full-length COI barcode based on 102 species of Korean birds to improve amplification success, and we attempted to identify bird species from 39 avian fecal samples collected during 4 months from Jinan, South Korea. Simultaneously, we conducted a dietary analysis using a universal DNA mini-barcode (Uni_Minibar) from same fecal samples. In silico analysis on newly designed mini-barcode represented that genetic distances were 0.5% in species and 9.1% in genera. Intraspecific variations of 149 species out of 174 species (86%) between Korea and North America were within the threshold (5.3% threshold in this study). From environmental fecal samples collected in Jinan, we identified seven avian species, which have high similarity (99-100%) with registered COI sequences in GenBank. Eight kinds of prey species, such as moth, spider, fly, and dragonfly, were identified in dietary analysis. We suppose that our strategy applying mini-barcode for environmental fecal samples, might be a useful and convenient tool for species identification and dietary analysis for birds.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.4
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• pp.455-466
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• 2014

Seasonal variations in species composition of catches were explored using seasonal samples caught by shrimp beam trawl in the Geum river estuary in 2011. During the study period, total catches were collected 91 species as fish 47 species, crustacean 28 species, mollusca 4 species, gastropoda 5 species, shellfish 3 species and others 4 species. The dominant species were Exopalaemon carinicauda, Eriocheir leptognathus, Palaemon gravieri, Mugil cephalus, Acanthogobius hasta, Cynoglossus joyneri, Pennahia argentata and Coilia nasus. The amount of species in spring and summer was higher than in autumn. The diversity index (H') was 0.43~0.96, evenness index (EI) was 0.14~0.25, and richness index (RI) was 1.54~4.25. Using cluster analysis 91 species were divided into 4 groups. Group I appeared mainly in spring and summer. Group II appeared only in summer. Group III appeared in winter and spring, and Group IV in spring and autumn.

• Journal of Korean Society of Rural Planning
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• v.15 no.2
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• pp.19-26
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• 2009

The purpose of this study is to build Island biogeography in the basic concept of landscape ecology in South Korea by draw relationship between the species side of quantitative habitats and forest area surveyed in the national database based on investigation of the 2nd natural environment. In addition, try to present criterion of habitats character category after understanding habitats character of emergence area side of quality habitats based on the type of formatting. Species and forest area relationship analyzed using correlation analysis and simple regression analysis. Also habitat character limited composition ratio of neighboring land cover and analyzed using hierarchical cluster analysis to classify type of habitat. As a result, we found that forest area is correlated with number of species, forests which is bigger than 100ha are more important of increase in species' population. And according to land cover composition ratio, bird's classified types of forest inner species, forest edge species, forest outer species and mammal's classified types of forest inner species, forest general species, forest edge species. We suggest that study of species-forest area relationship and emergence habitat character be used as some management plans of species' conservation, protection and restoration.