• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.6
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• pp.56-71
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• 2003

Waste landfills have been the center of environmental problems and they must be restored due to environmental pollution, disgusting landscape, and cost of management. It is suggested that they be recycled urban space as cities expand. Specially, nonsanitary waste landfills which have no pollution prevention facilities cause serious problems. Restoring the landfills as parks and golf courses, so on makes more benefits because of cheap use land, closeness to urban area, flat topography applicable to parks and golf courses, and high land values after restoration and the changes to local recreation sites. Restoration of waste landfills is a complex, costly, and interdisciplinary work. But, the waste landfill is a manmade ecosystem. Control, restoration and postmanagement of waste landfills are very important problems. The role of vegetation prevents soil erosion, reduces soil water storage, and obstructs leachate seepage. Early restoration makes derelict lands into man park artificially geared to soil, vegetation, landforms and hydrology. But, Ideal restoration is to make stable ecosystem nature-friendly and compatible with surrounding landscape without more management. Landscape is structured hierarchically with patches and stands as small components and forms forest as large components. Therefore, landscape formation of the waste landfills needs much restoration process. There are many ecological restoration techniques for the waste landfills. Those are divided into artificial and natural methods. The artificial method is anthropogenic plantings while the natural method is to trigger and use succession processes. The most important thing in the restoration of waste landfills is to consider the final restoration objectives of each waste landfill. According to these objectives, the depth of covering layer, planting degree, and structural design should be determined. The effective restoration methods should be selected of artificial and natural options.

• Journal of Korean Library and Information Science Society
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• v.4
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• pp.91-111
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• 1977

The view point of the library is treated as a first subject. This study is scheduled to construct, as a experimental study, the system of the Library Science. The study of this fields is called upon greatly because the trial to understand library as a socio-cultural phenomenon did not study as many times. As a result of the study, library is defined as ${\ulcorner}Structural Formation of Inquirying Behavior{\lrcorner}$. Not only technique and actual proof are possible in this study but also this definition is technical definition to indicate the main phenomenon of Librarial Behavior. This schedule represent the trial to define Library Behavior which could anticipate and fabricate when we analyze this definition First, we can find out, first of all, the researching behavior among the human behaviors and then human behavior has the condition of practice. At last, researching behavior can not have any result when it is a natural situation, it has only the meaning when it is guided by an obvious intention. The object of the library is just this human behavior. Second, Formation permits the guidance and self-control at the same-times. The answer about what we find out and practice make it possible the act of guidance. This guidance can't burden any subject but permit the people to result his own researching behaviors. He can save his activities, his own researching behaviors by the result of it. Third, The statematical means efficient performances, and them efficient performances is impossible, here is 'discoveries' of behavior itself. The system of the library is the formation of the relation between the accumulated civilizations and accumulated civilizations. As the definitions of the above mentions, library has the big abilities to the creation and succession of the civilization. As the contemporary view-points, there are some questions about the above described definition can meet it of the library. When we frame the science of library as the learning systems, we can't but the library as this definitions.

• Korean Journal of Veterinary Service
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• v.43 no.1
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• pp.39-44
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• 2020

The aim of this study is to investigate how the gut microbiome shifts when pigs were exposed with low concentrations of mycotoxins, deoxynivalenol (DON) and zearalenone (ZEN) in feed. Fifteen of pigs, 15 kg in weight which were negative for PRRSV and PCV2 were purchased, acclimatized until 20 kg in weight, and randomly divided into 3 groups; the DON group (DON treated), the ZEN group (ZEN treated) and the CTL (untreated negative control). DON and ZEN administered to each group for 30 days at 0.8 mg/kg (800 ppb) and 0.20 mg/kg (200 ppb) in feed, respectively. After extraction of microbial DNA from intestine and fecal samples, sequencing procedures were performed in the Ion PGM using an Ion 316 V2 chip and Ion PGM sequencing 400 kit. The results suggested that the bacterial communities in duodenum, jejunum and ileum of the DON and ZEN groups presented low-abundant OTUs compared with the CTL group. OTUs in cecum, colon and feces were determined more than in small intestine of all three groups. However, the CTL group yielded more OTUs than other two groups in inter-group comparison. It is not fully clarified how the richness and abundance in microbiome functions in the health condition of animals, however, the exposure to DON and ZEN has caused microbial population shifts representing microbial succession and changes following the diversity and abundance of porcine gut microbiome. The metabolomic analysis correlate with microbiome analysis is needed for further study.

• Korean Journal of Environment and Ecology
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• v.12 no.4
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• pp.345-360
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• 1999

The purpose of this study was to suggest vegetation management Planning and plant community structure of Camellia Japonica forest at Hakdong, Kojedo, Hallyo-Haesang National Park. Forty-six plots(l00$\m^2$/plot) were established in Camellia japonica forest and surveyed. By DCA ordination technique and mean importance value analysis, the plant communities were classified into four community types, which were Camellia japonica community, Camellia japonica-Eurya japonica community, Camellia japonica-Neolitsea sericea community, Chumaecyparis obtusa-Camellia japonica community. It was supposed that Camellia japonica-Neolitsea sericeu community succeeded to Neolitsea sericea community. The others would not be replaced by another woody species. The vegetation management for successional controls in long-term basis were suggested; for the short-term basis, the species of Chamaecyparis obtusa, Neolitsea sericea and Eurya japonica should be removed. The species of Quercus serrata, Prunus sargentii, Meliosma myriantha, Machilus thunbergii and Litsea japonica. must be controlled under the long-term management of vegetation.

• Ocean and Polar Research
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• v.31 no.1
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• pp.63-70
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• 2009

Eutrophicated water fed through Mankyeong River and Dongjin River into the new Saemankeum Lakemight seriously affect the water quality and phytoplankton community in the lake. To obtain control reference data for the later studies on environmental changes due to the construction of the Saemankeum Sea Wall, we performed a monthly investigation on the physico-chemical properties of the water and phytoplankton community at 3 stations in the Mankyeong River Estuary over 14 months starting from September 1999. Water temperature ranged from $0.3{\sim}32.9^{\circ}C$ due to the typical seasonal variations in temperate on the coasts and salinity exhibited a wide annual range of $0.2{\sim}33.7$ psu along with regular and huge hourly variations according to tidal cycles. Inorganic nutrients were supplied from rivers to the monitoring station and the whole lake. The average concentration of total-N, $6.99\;mg{\cdot}l^{-1}$, was higher than the water quality for agricultural use with peak values occurring in winter. Species composition showed a seasonal succession pattern, where a high diversity was observedin summer and autumn and vice versa in winter. Hourly variations of water properties in the "Mankyeong bridge" Station were quite regular and well in accordance with the daily tidal cycles. The different degree of sea water intrusion during the flood tide at each of the 3 stations exhibited a different range and variation pattern of water temperature and salinity throughout a day. Hourly changes in species composition were in harmony with the daily tidal cycles, resulting in extremely variable spatio-temporal variation.

• Journal of Digital Contents Society
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• v.18 no.4
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• pp.795-802
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• 2017

If the function of the national infrastructure is suspended due to natural disasters and social disasters, the damage of the national infrastructure can be a serious threat to the national security as well as the life, body and property damage of the people. In this paper, we examine the domestic and overseas trends of the national system protection system and examine the domestic and overseas trends of the national system protection system. The detailed function of the essential function continuity, essential function, succession order, authority delegation, continuity facility, continuity communication, We examined the specific issues related to testing, education and training, transferring control and directing authority, analyzing the system related to the national infrastructure protection plan, and examined the specific problems and suggested an effective improvement plan for the critical infrastructure protection system.

• Journal of Periodontal and Implant Science
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• v.52 no.5
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• pp.383-393
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• 2022

Purpose: Aloe-emodin (AE), a natural anthraquinone abundant in aloe plants and rhubarb (Rheum rhabarbarum), has long been used to treat chronic inflammatory diseases. However, AE's underlying mechanisms in periodontal inflammation have not been fully elucidated. Acidic mammalian chitinase (AMCase) is a potential biomarker involved in bone remodeling. This study aimed to evaluate AE's effect on periodontitis in rats and investigate AMCase expression. Methods: Eighteen Sprague-Dawley rats were separated into the following groups: healthy (group 1), disease (group 2), vehicle (group 3), AE high-dose (group 4), and AE low-dose (group 5). Porphyromonas gingivalis ligatures were placed in rats (groups 2-5) for 7 days. Groups 4 and 5 were then treated with AE for an additional 14 days. Saliva was collected from all groups, and probing pocket depth was measured in succession. Periodontal pocket tissues were subjected to histomorphometric analysis after the rats were sacrificed. Bone marrow-derived macrophages and murine macrophages were stimulated with receptor activator of nuclear factor-κB ligand (RANKL) and treated with different concentrations of AE. AMCase expression was detected from the analysis of saliva, periodontal pocket tissues, and differentiated osteoclasts. Results: Among rats with P. gingivalis-induced periodontitis, the alveolar bone resorption levels and periodontal pocket depth were significantly reduced after treatment with AE. AMCase protein expression was significantly higher in the disease group than in the healthy control (P<0.05). However, AE inhibited periodontal inflammation by downregulating AMCase expression in saliva and periodontal pocket tissue. AE significantly reduced RANKL-stimulated osteoclastogenesis by modulating AMCase (P<0.05). Conclusions: AE decreases alveolar bone loss and periodontal inflammation, suggesting that this natural anthraquinone has potential value as a novel therapeutic agent against periodontal disease.

• Journal of Korean Society of Forest Science
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• v.98 no.1
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• pp.94-105
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• 2009

Black locust (Robinia pseudoacacia) stand is representative lowland exotic plantation with low ecological quality and arrested succession in South Korea. To facilitate succession and restore natural vegetation, small canopy gaps (${\sim}57m^2$), which can modify minimally structural variables and reduce restoration related disturbances on stand, was established in the black locust stand, and oak (Quercus serrata) seedlings were introduced in the gap. Two types of varying levels were introduced for gap creation; cutting (C) and girdling (G) on canopies. Understory removal (CU and GU) treatment was applied as subtypes of structural modification. Growth (diameter, height and leaf area) of target species and responses (species composition, diversity and coverage) of understory community were monitored during study years (2007~2008). Canopy openness was different significantly among treatments but not for light availability. Based on the result of logistic regression, growth of height and leaf area of seedlings were significant variables on seedling survival. Height and leaf area of seedlings were increased during study years, although radial growth was reduced. During study years, there were no significant differences in species composition and diversity, and total coverage increased about 20%. Increase of resources by gap creation and understory removal likely affect growth of target species. Small gap creation was effective to reduce understory responses in composition and diverstiy. Synthesized, growth of target species and responses of understory community to small canopy gap creation exhibited, in short term, possibility of utilization in alternative forest restoration and management option. Long-term monitoring is necessary to certificate effect of artificial gap creation on forest restoration.

• Korean journal of applied entomology
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• v.15 no.3 s.28
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• pp.111-126
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• 1976

Regional differences in economic importance of the four species of rice leafhoppers, viz., Laodelphax striatellus, Nephotettix cincticeps, Nilaparvata Iugens and Sogatella furcifera, were analyzed and discussed based on population surveys conducted in Suweon and in southern and south-western coastal areas. The economic importance of L. striatellus and N. cincticeps, which are found throughout the year in Korea, seems to be less in middle regions. This is believed due to effective natural control through severe winter climate, cultural practices in rice and barley growing, and natural enemies such as spiders. However, the economic importance of these two species is significantly greater in southern regions with a less severe winter climate, and where cultural practices in rice and barley favour synchronization between the life cycles of insects and the seasonal succession of host plants. with regard to N. lugens and S. furcifera, which cannot overwinter in Korea, initial populations are the result of long distance migration across the East China Sea. Weather elements related to their migration result in more abundant immigrants of these two species in southern than in middle regions. Thus, different policies are needed for the integrated control of rice leafhoppers in middle and southern Korea.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.590-598
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• 2015

Despite various control methods for pine wilt disease, the disease has been increasing at an alarming rate every year in Korea. Still there is a lack of research on the problems of the current methods used to curb the disease. One main method to control pine wilt disease is fumigation for eliminating the larva of the pine sawyer beetle (Monochamus alternatus) which is known as the vector insect for pine wilt disease. We surveyed and analyzed the amount of destroyed uninfected trees in the fumigated area by studying 32 survey plots ($100m^2$) in Miryang city. The destroyed trees' crown area was estimated by induced regression between root collar area and crown area of the remaining trees (coniferous tree: $R^2=57.4$, deciduous broad-leaved tree: $R^2=63.8$). According to the analysis results, the infected trees (cut trees) were 18.7% and cut trees which were not infected were 35.5% of the total tree population of the study area on the basis of total crown area. In case of pine trees, 8.4% of uninfected trees were cut off but 62% of uninfected deciduous broad-leaved trees including Quercus spp. were affected and damaged during the fumigation process. Since these broad-leaved trees dominate the sub-canopy layer of the forest, this indiscriminate interruption of broad-leaved trees has the adverse effect of depriving the public benefits such as shadow, a cooler weather, controlling humidity, etc.