• Journal of Korean Society of Forest Science
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• v.96 no.5
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• pp.567-571
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• 2007

This study was conducted to clarify the differences in breeding bird communities between deciduous forests of Gwangneung and Mt. Namsan areas from April to August 2006. Two 10ha area were selected for territory mapping of breeding bird community in both study area. The DBH distribution of trees and average foliage profiles were significantly different between study areas. Also, breeding bird communities were different. Number of breeding species and pairs, breeding density, and bird species diversity were higher in Gwangneung area than in Mt. Namsan area. When examining relationship between forest habitat structure and bird community, Number of bird species and breeding pairs belonged to hole and canopy guild were increase as the increase of coverstory coverage and number of large trees. Therefore, it is necessary to make vertical structure more various to plant bushes, and to make DBH distribution more diverse for enhancing bird species diversity in the degraded ecosystem.

• Ocean and Polar Research
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• v.22 no.1
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• pp.37-43
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• 2000

Epiphytic communities on marine plants of Seychelles (Indian Ocean Island group associated with East Africa) were investigated in January - March of 1989 during the $15^{th}$ biological voyage of the research vessel cademic Alexander Nesmeyanov. A seagrass species, Thalassodendron ciliatum, and macroalgae (Sargassum spp. and Halimeda spp.) were tested for host substrates and biomass of their dominant epiphytes were assessed. Also, in order to understand the effect of shading and nutrient filtering by epiphytes, two series of photosynthetic rates were compared for Th. ciliatum host leaves having 10% and no epiphytes. Total of 84 species of algae and main taxons of benthic animals were identified from three different host plants. An average biomass of the epiphytes on Th. cihiatum was $184.6g\;kg^{-1}$ and dominant species were green alga Halimeda opuntia, red algae Dictyurus occidentalis and Gelidiella myrioclada. These dominant species and their biomass were remarkably varied with depth increment. On Sargassum spp., an average biomass of the epiphytes was $0.18g\;kg^{-1}$ and the maximum biomass was never exceeded $0.16g\;kg^{-1}$. In the case of Halimeda spp. an average biomass of the epiphytes was $8.0g\;kg^{-1}$, and dominant species were Peyssonnelia dubyi, sponges and decapods. Photosynthetic rates of Th. ciliatum were significantly reduced in the leaves having 10% epiphytes (1.72 times lower, t=6.718, p<0.001).

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2005.11a
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• pp.43-49
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• 2005

The purpose of this study was to provide the fundamental data for the gradual apartment management plan. Through the questionnaire survey, residential satisfactions and maintenance consciousness were investigated. As the result of statistic analysis, the residents' needs for improvement according to the life span of apartment communities were found out. And we can also compare the differences about maintenance consciousness to the life span of apartment. The major research findings are as follows. First, the satisfaction averages according to the life span of apartment communities were classified two groups, less than 10 years' and over than 10 years'. By the requirement for improvement according as the life span apartment communities, habitability factors was demanded in less tham 10 years' group and safety factors was required in over than 10 years' group, Second, dwellers have high preference about remodeling to reconstruction. Especially we have to pay attention to the result that positive consciousness of remodeling and long term reparative marked highly in the group which has the short elapsed years. These results represent the possibility gradual step-by-step remodeling. In other words, the object of remodeling is not only odeteriorated apartments but also new apartments to have short elapsed years.

• The Korean Journal of Ecology
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• v.15 no.3
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• pp.209-220
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• 1992

We investigated major plant communities and seed dispersal patterns in areas a(alt. 2,263 ~2,350m),b(alt. 2,350~2,420m), c(alt. 2,420m) with levels of a crater on mt. paektu. Thirty two species distributed around chunji consisted of 24 perennial herbs, 1 biennial herb and 7 alpine dwarf shurbs. Their fruit types were quite diverse; capsule(11), achene(10), grain(4), legume(2), follicle(2), schizocarp(2) and drupe(1). in area a, adjancent to the chunji(lake) water surface, gramineae sp., cyperaceae sp., chrysanthemum zawadskii and bistorta ochotensis were occured as members of the major plant communities. Species of gramineae and cyperaceae seem to have become dominant because their seeds float well. Astragalus membranaceus is legume and endures the winter cold and summer drought. in area c, alpine dwarf shrubs (e. g.rhododendron redowskianum, rhododendron aureum, empetrum nigrum) were dominant. In area c, compared to a and b, the weather is drier because of strong wind and lower water holding capacity of the soil. Therefore the pattern of plants distributing around chunji is different from that in western slope on mt.paektu. environmental factor such as wind, temperature and water may contribute to the pattern.

• Mycobiology
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• v.45 no.4
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• pp.312-317
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• 2017

Orchidaceous plants have symbiotic relationships with endophytic fungi, including mycorrhizal fungi, which play important roles in the seed germination and growth of the host plants. In this study, endophytic fungal communities isolated from the roots of Cephalanthera longibracteata collected from three different sites in Korea were analyzed, and it was determined whether fungal communities were preferentially correlated with the sites. The fungal isolates were identified by sequence analysis of the internal transcribed spacer regions of rDNA. In total, 30 species of endophytic fungi, including two species of mycorrhizal fungi belonging to the genus Tulasnella, were identified. Leptodontidium orchidicola showed the highest frequency and was isolated from all root samples. Species diversity and richness were not significantly different among sites. However, the community structure of the endophytic fungi significantly differed among sites, suggesting that the site characteristics affected the community composition of the endophytic fungi colonizing the roots of C. longibracteata. Our findings will aid in developing methods involving the use of symbiotic fungi for orchid conservation and restoration in native habitats.

• Membrane and Water Treatment
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• v.10 no.6
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• pp.395-404
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• 2019

The influence of chlorine on marine bacterial communities was examined in this study. A non-chlorine-adapted marine bacterial community (NCAM) and a chlorine-adapted bacterial community (CAM, bacterial community treated with $0.2mg-Cl_2/L$ chlorine) were cultivated for 1 month. A distinct difference was observed between the NCAM and CAM, which shared only eight operational taxonomic units (OTUs), corresponding to 13.1% of the total number of identified OTUs. This result suggested that chlorine was responsible for the changes in the marine bacterial communities. Kordiimonas aquimaris was found to be a chlorine-resistant marine bacterium. The effect of intermittent chlorination on the two marine biofilm communities formed on the reverse osmosis (RO) membrane surface was investigated using various chlorine concentrations (0, 0.2, 0.4, 0.6 and 0.8 mg $Cl_2/L$). Although the average number of adherent marine bacteria on the RO membrane over a period of 7 weeks decreased with increasing chlorine concentration, disinfection efficiencies showed substantial fluctuations throughout the experiment. This is due to chlorine depletion that occurs during intermittent chlorination. These results suggest that intermittent chlorination is not an effective disinfection strategy to control biofilm formation.

• Journal of Information Science Theory and Practice
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• v.9 no.2
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• pp.83-98
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• 2021

Research collaboration is an important strategy to improve research output, and virtual academic communities (VACs) have become an important platform to collaborate on. This paper reveals the influencing factors of researchers' collaboration intention in VACs from two attributes: individual, and inter-members. On the basis of the Social Cognitive Theory, Social Exchange Theory, social network theory, and Five-Factor Model, this paper constructed a model demonstrating the influencing factors of VACs researchers' collaboration intention. A self-administered questionnaire was employed on members of four VACs in China to collect data; subsequently, 558 usable responses were analyzed using structural equation modeling. The result showed that openness, conscientiousness, reciprocity, trust, and the social network characteristic had a significant influence on the collaboration intention of researchers in VACs, while self-efficacy, agreeableness, extroversion, neuroticism, and experience had no significant effects on the collaboration intention of researchers in VACs. This model plays a positive role in promoting the research collaboration intention of Chinese VACs researchers and in guiding the construction of VAC platforms.

• The Plant Pathology Journal
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• v.38 no.3
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• pp.203-211
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• 2022

Bacterial wilt, which is a major soil-borne disease with widespread occurrence, poses a severe danger in the field of tobacco production. However, there is very limited knowledge on bacterial wilt-induced microecological changes in the tobacco root system and on the interaction between Ralstonia solanacearum and fungal communities in the rhizosphere soil. Thus, in this study, changes in fungal communities in the rhizosphere soil of tobaccos with bacterial wilt were studied by 18S rRNA gene sequencing. The community composition of fungi in bacterial wilt-infected soil and healthy soil in two tobacco areas (Gengma and Boshang, Lincang City, Yunnan Province, China) was studied through the paired comparison method in July 2019. The results showed that there were significant differences in fungal community composition between the rhizosphere soil of diseased plants and healthy plants. The changes in the composition and diversity of fungal communities in the rhizosphere soil of tobaccos are vital characteristics of tobaccos with bacterial wilt, and the imbalance in the rhizosphere microecosystem of tobacco plants may further aggravate the disease.

• Iberoamérica
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• v.23 no.2
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• pp.209-241
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• 2021

Over the last few years, rural areas in northeastern Mexico have present significant changes in social, economic, and territorial aspects linked to the New Rurality. In this context, winemaking has become one of the most dynamic and growing activities in the regional economy. This emerging development has prompted different forms of appropriation and use of this space, but it also highlights the lack of access to knowledge for wine production due to the lack of formal educational centers. As a result, learning communities enable the development of skills and competencies through non-formal educational practices. The objective of this paper is to analyze the role of learning communities in non-formal educational environments, taking as a case study: a collective of small-scale wine producers in Parras de la Fuente, Coahuila. This research focuses on two perspectives of learning: appropriation and technology transfer, and promotion of Mexican wine culture. The main finding was to demonstrate the importance of including educational processes that respond to the context and needs of the community.

• The Korean Journal of Applied Statistics
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• v.36 no.5
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• pp.399-413
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• 2023

Recently, monitoring and detecting anomalies in social networks have become an interesting research topic. In this study, we investigate the detection of abnormal changes in a network modeled by the DCSBM (degree corrected stochastic block model), which reflects the propensity of both individuals and communities. To this end, we propose three methods for anomaly detection in the DCSBM networks: One method for monitoring the entire network, and two methods for dividing and monitoring the network in consideration of communities. To compare these anomaly detection methods, we design and perform simulations. The simulation results show that the method for monitoring networks divided by communities has good performance.