• Journal of Wetlands Research
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• v.2 no.1
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• pp.19-29
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• 2000

The physico-chemical characteristics of core sediment, community dynamics of Salix species during the sedimentation were investigated in 1990~1997 for the purpose of inquiry to reveal the effects of terrestrialization on the environment and plant community in a natural wetland. The study site, Paksil-nup wetland was a valley blocked lake located near Hwang-River, Hapcheon-gun, Gyeongsangnam-do, Korea. The values of conductivity, organic matter, total nitrogen, exchangeable K, and exchangeable Ca were higher, and pH was lower in the upper layer of the core sediment. Soil properties such as available phosphorus, exchangeable Ca, exchangeable Na increased, and organic matter, total nitrogen, exchangeable K decreased during the sedimentation. Salix nipponica was the dominant species, and Salix glandulosa was subdominant among 10 Salix species. Sahx species were supposed to be the pioneer plants in shrub and tree layers during the succession in Paksil-nup wetland. Age class of SaliX species community from the epilittoral zone to the infralittoral zone were low, and age of Saljx species distributed from 2 years to 11 years. DBH, height, mean number of branches, number of herb species, and light intensity were increased, whereas density was decreased from a lower age to a higher age community. Salix nipponica was superior than Sahx purpurea var. japonica and other Salix species during the interspecific competition among Salix species.

• The Korean Journal of Archival Studies
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• no.49
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• pp.247-275
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• 2016

The classification scheme of records indicates a table that intends to express organic relations between records by organizing records and enabling internal order. Although the principles of organic classification have remained in traditional records management environment, they have been changed to "function and business" in the modern times. Therefore, Korea introduced a business reference model (BRM) based on function and business from 2008 and subsequently implemented its operation. However, it has been pointed out that the roles of the classification scheme of records have not been played because the analysis of "Danwigwaje," which belongs to the lowest level of business reference models, is poor. According to this indication, the Gangbuk District of Seoul Special City established a functional classification scheme by executing a business process analysis of "Danwigwaje." First, the record manager carried out analyses on the principles of "Danwigwaje," small function, and "Danwigwaje." Then, the functional classification scheme of "Danwigwaje" was modified by looking into the opinion inquiry process of the treatment department and performing a test operation. Through the case of the Gangbuk District in Seoul Special City, analytical procedures and methods of "Danwigwaje," as well as implications according to the establishment of a functional classification scheme of basic local governments, were arranged in a written format.

• Journal of The Korean Association For Science Education
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• v.40 no.6
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• pp.671-685
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• 2020

The purpose of this study is to critically examine the relationship between 'academic disciplines', 'subject', 'subject content', and 'subject matter education' as an attempt to explore the meaning and identity of subject matter education. In this study, first, we looked at the origin of the 'separative' perspective, focusing on science education, and the effects of this perspective on the relationship between 'academic discipline', 'subject', 'subject content', and 'subject matter education'. In addition, the relationship between them was examined from 'essential-holistic' perspective. As a result of the study, it was found that the 'separative' perspective has limitations in grasping the organic and overall relationship between 'academic discipline', 'subject', 'subject content', and 'subject matter education'. Therefore, we need to overcome the existing 'separative' perspective in order to go beyond the current horizon. On the other hand, the 'essential-holistic' perspective shows a close relationship that is not essentially separated between 'academic discipline', 'subject', 'subject content', and 'subject matter education'. It is expected as a perspective that can help solve the teacher education problem caused by the 'separative' perspective.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.1
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• pp.51-62
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• 2009

This study was carried out development a new composting system to lower copper and zinc concentration in plg sludge compost and conduct an inquiry into the possibility of crop cultivation. The concentrations of nitrogen, phosphorus and pH averaged 4.4%, 6.3% and 7.57, respectively, which were higher concentrations than in commercial organic fertilizers, and the concentrations of copper and zinc averaged 805 and 1,704 mg/kg, respectively, which were beyond the heavy metal concentration limit in byproduct compost. Hydrated citric acid I lowered the concentrations of copper and zinc by 58% and 97%, respectively and hydrated oxalic acid II lowered the concentrations of copper and zinc by 48% and 56%, respectively in pig sludge compost. Lower concentrations of copper and zinc in pig sludge resulted from the enhanced hydrated-citric acid concentration in organic acid solution mixed with distilled water. The concentrations of copper and zinc were 330, and 41 mg/kg in the pig sludge treated with 100% hydrated citric acid. Agitation composting system stabilized the compost earlier than the stationary composting system, in which the stabilization condition was confirmed by higher temperature by $4^{\circ}C$ at highest temperature and 7 days earlier cooling down after highest temperature. The levels of germination index (G.I) 80 were obtained 15 and 20 days after composting in agitation and stationary composting system, respectively. The concentrations of copper and zinc were 2.4 and 4.26 mg/kg respectively in soils amended with pig sludge compost after removing process of heavy metals by citric acid, but 8.0 and 22.37 mg/kg, respectively in soils amended with Pig Sludge. The concentrations of heavy metals was highest in com cultivated in soils amended with pig sludge. The copper and zinc concentrations In corn leaves were 75.2 and 50.56 mg/kg respectively, which were 4 and 2 fold higher than the com cultivated in soils amended with pig sludge compost after heavy metal removing process by hydrated citric acid.

• Korean Journal of Environmental Biology
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• v.34 no.4
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• pp.320-328
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• 2016

This study was conducted to provide important basic information about effective management of the marine environment at major inflow streams in Lake Andong and Lake Imha. The investigation was conducted 8 times from May, 2015 (AD1, AD2, IH1, IH2) to September, 2016 (AD3, AD4, IH3, IH4), and 8 surveyed sites were selected at Lake Andong (4 sites) and Lake Imha (4 sites). The inquiry identified 114 species, $59,913.7inds.\;m^{-2}$ in Lake Andong and 112 species, $39,038.4inds.\;m^{-2}$ in Lake Imha. The results indicate that the number of species and individuals in Lake Andong is more than that in Lake Imha, because Lake Andong has a variety of riparian vegetation and a richness of organic materials. Community analysis at Lake Imha revealed a dominant index of 0.57 (${\pm}0.18$), a diversity index of 2.87 (${\pm}0.31$), an evenness index of 0.73 (${\pm}0.04$), and a richness index of 4.17 (${\pm}0.71$). The results of functional feeding group analysis showed that a high proportion of species and individuals are gathering collectors. The results of functional habitat group analysis showed that a high proportion of species and individuals are clingers. The result of a physico-chemical water assay and dissolved oxygen and electric conductivity tests revealed that these measures increased when the water temperature decreased. The result of Pearson's correlation analysis by biological factors and physico-chemical factors showed that species and electric conductivity are highly correlated with one another. Major inflow streams of Lake Andong and Lake Imha were exposed to various point pollution sources and non-point pollution sources. This implies a necessity for continuous monitoring of the aquatic ecosystems in order to effect systematic water quality management of Lake Andong and Lake Imha.