• Development and Reproduction
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• 제24권4호
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• pp.317-325
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• 2020

The Far Eastern catfish (Silurus asotus) is an important commercial freshwater fish in Korea. Investigation of the genetic diversity of wild and cultured domestic catfish groups is essential for the restoration of fishery resources and for increasing local revenue. However, there are relatively few genetic diversity studies on wild and cultured catfish in Korea. In the present study, we analyzed the genetic diversity and association of wild and cultured catfish using five microsatellite markers. We determined that the number of alleles per locus (N_A) ranged from 9 to 25, wherein the Jeonbuk catfish demonstrated the highest mean number of alleles per locus and the cultured catfish exhibited the lowest. The average expected heterozygosity (He) of the wild catfish samples was 0.907, and that of the cultured catfish showed was 0.875. The genetic distances (GD value) among populations of all catfish ranged from 0.138 to 0.242. Jeonnam and Jeonbuk wild catfish were located closest to each other, and the cultured group was separated from the other groups. In conclusion, the present study confirmed that the genetic diversity of wild and cultured catfish was maintained at a high level. In the case of the wild group, it is effective in maintaining diversity due to the continuous fry release by the local fish research institute. However, the genetic diversity of cultured catfish declined. Low diversity is associated with slow growth and weakened immunity, and therefore continuous monitoring is necessary.

• Korean Journal of Organic Agriculture
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• 제18권3호
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• pp.291-313
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• 2010

The objective of this paper is to apply choice experiment methods to estimate non-market value of organic farming and its policy implication. A preliminary survey shows that the attributes of organic farming are reduce environmental pollution, bio-diversity improvements, cultural diversity improvements and maintain local community, reduce green-house gas emissions, energy saving, landscape improvements and tax for organic farming improvement policy. Questionnaire was eight different choice sets presented to each respondent. Implicit values of the attributive levels of organic farming have been calculated into tax money costs per house. This paper compared the six feasible scenarios in terms of willingness to pay per year. This study is expected to contribute to government's organic farming policies and quantitative information related to practice of organic farming.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• 제50권
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• pp.187-212
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• 2011

Third party logistics research is searching for increasing its logistics efficiency of organization. Perspective of resource-based theory, this study is to reveal the exploratory relation between integrated capabilities, organzaiton knowledge, and service performance. To develop the relational model, this study conducted a theoretical survey on Shang(2009)'s 3PL service providers research model and Synder & Cumming(1998)'s learning of organization knowledge. According to the result of correlation analysis, Integrated organization knowledge is positively correlated with service diversity advantage (correlation coefficient= .670, p-value= .000) and service quality advantage (correlation coefficient= .575, p-value= .000). The thesis argued that Korean companies try to apply integrated organization abilities and service performance for cutting their export expense.

• Korean Journal of Plant Resources
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• 제10권3호
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• pp.258-264
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• 1997

The introduction of molecular biology methodologies to plant improvement programs offers an invaluable opportunity for extensive germplasm characterization. We have applied the developed technique of random amplification of polymorphic DNA(RAPD)to the analysis of evaluating genetic diversity among Korean wild Codonopsis lanceolata. A total of 340 polymorpic hands were gernerated on agarose- and polyacrylamide-gel by 19 primers of abitrary sequence. grouped by cluster analysis using sample matching coefficients of similarity. Among of the samples. the minimum genetic distance value was obtained between sample no. 1(Girisan) and no. 2(Girisan), and the largest value between sample no. 11(Sulaksan) and no. 17(Sulaksan).In separate cluster dendrograms based on agareose - and polyacryamide-gel. some differences were observed; In the case of agarose gel,41 samples could be devided into 7 groups at below about 0.44 level of distance. However they were divided into 6 gourps at below about 0.40 level of distance in the case of polyacrylamide gel. These results showed that polymophic data in agrose were not grouped to wild plant selected from each mountainous district except for wild plants selected from Sulaksan and Chiaksan. We believe that polyacrylamide-RAPD is a superior method for detecting DNA polymorphism compared to agarose-RAPD method.

• Journal of Dairy Science and Biotechnology
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• 제35권3호
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• pp.184-195
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• 2017

This study was carried out to investigate the micro-agribusiness realities of dairy farms by surveying both farmers' opinions and consumers' recognition of dairy farm products for in a value-chain analysis. In most cases, dairy farms produced fermented milk for sales and to prepare cheese both for sales and for providing the necessary material for farm visitors. Value-chain analysis did not seem to be a viable strategy for dairy farmers, except when assessing the quality of farmstead milk products in comparisons of dairy farm milks and commercial milk products. Consumers had a wide range of experience with milk products and had no willingness to buy products from dairy farms because of the high cost and the lack of product diversity. Our findings established three strategies for improving the economic feasibility of dairy farms. First, the price should be reduced by adopting a production balance to establish a farm-gate price, i.e., not as quota milk but as surplus milk. Second, consumers should be educated on the prescription of cheese at home. Third, a value-chain based on cooperative partnerships should be established among dairy farms. In addition, to improve the consumers' satisfaction on the diversity and quality of farm dairy products, developments of new value-added milk products made from the milk of cows allowed to graze on mountain pastures are needed.

• The Journal of the Korea Contents Association
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• 제16권11호
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• pp.456-463
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• 2016

This study investigates the relationship between the digital music service acceptance factors on the Perceived value, and Customer Satisfaction. Remarkable points of this study are as follows. First, according to the result of the analysis of relationship between digital music service acceptance factors and perceived value, diversity of digital music products and quality of digital music system affects significantly on the perceived value. but, usability of digital music service use does not have an effect on the perceived value. Second, as the result of analysis of the relationship between digital music service acceptance factors and customer satisfaction, diversity of digital music products, usability of digital music service and quality of digital music system affects significantly on the perceived value. These finding should assist digital music marketers and academics in their understanding of building loyalty on digital music service.

• Journal of Practical Engineering Education
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• 제11권2호
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• pp.305-311
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• 2019

Many universities offer mileage system as part of their student reward program. The mileage system provides mileage to students who participated in on-campus extracurricular programs, and awards scholarships regardless of grades based on the mileage earned. The purpose of this study is to identify the effect of students' perception of college mileage system on loyalty and to compare the difference in loyalty between those who received mileage and those who did not. To this end, the effect of loyalty was studied empirically by classifying the perception of college mileage into five categories: the cash value, aspirational value, diversity of benefits, convenience, and relevance. The results showed that aspirational value, diversity of benefits and relevance had a positive effect on loyalty, while cash value and convenience did not. In addition, the effect of cash value on loyalty was higher in those who received mileage than those who did not. In terms of relevance, higher loyalty was found in group that did not receive mileage than those who did.

• Journal of Forest and Environmental Science
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• 제33권1호
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• pp.66-73
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• 2017

This study was conducted to evaluate the ecological attributes of forest types which were classified by cluster analysis in the natural forest of Mt. Odae on the basis of the vegetation data (232 sampling points) from the point-quarter sampling methods. For the classified types, the species composition was expressed by importance value to describe the stand structure and the species diversity was quantified using the Shannon's diversity index. Recognized forest types were 1) Quercus mongolica-Pinus densiflora-Betula ermanii forest type, 2) Mixed mesophytic forest type, 3) Q. mongolica forest type, 4) B. ermanii forest type. Species diversity indices of total and overstory were highest in the Mixed mesophytic forest type (3.465 and 2.942), and lowest in the B. ermanii forest type (0.118 and 0.832). In addition to that, Q. mongolica-P. densiflora-B. ermanii forest type was calculated as 3.226 and 2.565, and Q. mongolica forest type was calculated as 2.776 and 1.218 in total and overstory, respectively. It was considered that after the P. densiflora and B. ermanii first invaded and site condition became good, Q. mongolica-P. densiflora-B. ermanii forest type was dominated by Q. mongolica. Mixed mesophytic forest type showed the most stable stand structure with various species distributed uniformly. Q. mongolica forest type would preserve the present stand status for a while, and the B. ermanii in B. ermanii forest type would be pressed by other species over time.

• Journal of Ecology and Environment
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• 제45권3호
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• pp.97-104
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• 2021

Background: Asarum sieboldii Miq., a species of forest understory vegetation, is an herbaceous perennial belonging to the family Aristolochiaceae. The metapopulation of A. sieboldii is distributed sparsely and has a short seed dispersal distance by ants as their seed distributor. It is known that many flowers of A. sieboldii depend on self-fertilization. Because these characteristics can affect negatively in genetic structure, investigating habitat structure and assessment of genetic structure is needed. A total of 27 individuals in a valley were sampled for measuring genetic diversity, genetic distance, and genetic differentiation by RAPDPCR. Results: The habitat areas of A. sieboldii metapopulation were relatively small (3.78~33.60 m²) and population density was very low (five to seven individuals in 20×20 m quadrat). The habitat of A. sieboldii was a very shady (relative light intensity = 0.9%) and mature forest with a high evenness value (J = 0.81~0.99) and a low dominance value (D = 0.19~0.28). The total genetic diversity of A. sieboldii was quite high (h = 0.338, I = 0.506). A total of 33 band loci were observed in five selected primers, and 31 band loci (94%) were polymorphic. However, genetic differentiation along the valley was highly progressed (G_st = 0.548, N_m = 0.412). The average genetic distance between subpopulations was 0.387. The results of AMOVA showed 52.77% of variance occurs among populations, which is evidence of population structuring. Conclusions: It is expected that a small-scale founder effect had occurred, an individual spread far from the original subpopulation formed a new subpopulation. However, geographical distance between individuals would have been far and genetic flow occurred only within each subpopulation because of the low density of population. This made significant genetic distance between the original and new population by distance. Although genetic diversity of A. sieboldii metapopulation is not as low as concerned, the subpopulation of A. sieboldii can disappear by stochastic events due to small subpopulation size and low density of population. To prevent genetic isolation and to enhance the stable population size, conservative efforts such as increasing the size of each subpopulation or the connection between subpopulations are needed.

• Journal of Forest and Environmental Science
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• 제37권2호
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• pp.104-115
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• 2021

The research attempted to analyze the medicinal plant species richness in the vertical gradient from lower to the highest elevation of Makawanpur, focusing on the relationship between species richness and elevation which is very important for conservation and management of species diversity. Inventory was carried out in the study area by taking sampling intensity of 0.5% in the effective area. Altogether, 42 sample plots were laid in the field with the help of GIS software maintaining 50 m altitude difference. High species diversity was found in the herbs species whereas shrubs have comparatively low species diversity. The maximum species richness is found in herbs and poles whereas shrubs and trees have relatively low species richness. Research showed that species richness of medicinal plants increased with altitudinal gradient. While analyzing the species richness from 350 to 2,550 m (msl), the highest species richness was received with the elevation ranges from 1,800 m to 2,300 m. There was a positive relationship between species richness and altitudinal gradient in the study area. In addition, we have recorded the high value medicinal plants after 1,800 m altitude and rarely within 1,000 m. Medicinal plants correlated both positive and negative relationships with the increased altitude. The altitudinal response has positively seen except density (n/ha) of Shrubs. Domestication and cultivation of high value medicinal plants should be promoted in community forest including private lands. Training, workshops and awareness programs should be conducted to make people aware about medicinal plants resource utilization, conservation and commercialization of available medicinal plants.