• Korean Journal of Environment and Ecology
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• v.11 no.2
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• pp.160-165
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• 1997

The objective of this study was to analyze dominance-diversity of Quercus mongolica community which characterize the boreal-temperate deciduous forest in Korea. Employing the releve method of Muller-Domboes and Ellenberg, 100 quadrats were sampled in the natural forest of Mt. Odae, Mt. Chumbong and Mt. Jungwang in Kangwon-do, where Quercus mongolica community is in the situation of climax or subclimax. On the basis of Braun-Blanquet method, field survey, which accounts ffor the characters of the species structure of Quercus mongolica community, was carried out between 1991 and 1994. Quercus mongolica community was relatively in a stable condition because of the even distribution of its various indices: the species diversity index was 0.4~1.2; the species richness index was 2~11; the evenness index was 0.6~0.9. The dominance-diversity curve were comparatively of lognormal distrivution with a gentle slope in all communities. The species sewuence curve for Quercus mongolica - Lindera obtusiloba community had relatively a steep slope, which meant that the evenness of the community would be low. The species sequence curve for Quercus mongolica - Carpinus cordata community had a slow slope, which meant that the evenness and the stability of the community would be high.

• Ocean and Polar Research
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• v.31 no.1
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• pp.71-76
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• 2009

Drastic changes in the water quality and phytoplankton community of the new Saemankeum Lakeduring the first decade following the construction of the Saemankeum Sea Wall has been considered to be unavoidable. Input of eutrophicated water through the Mankyeong River and Dongjin River might produce more direct effects on the water quality and phytoplankton community, which lead us to launch a long-term semi-weekly investigation at the "Mankyeong Bridge" monitoring point to resolve its short-term effect as well as long-term stabilization of the ecosystem in the new Saemankeum Lake. During 15 months starting from June 2006, the water temperature varied in accordance with the typical seasonal variations in temperate on the coasts, and no significant daily variations evoked by tidal cycle could be detected. However, there was an inverse relationship between seasonal precipitation and salinity even though the range in annual variation was drastically reduced right after the construction of the Saemankeum Sea Wall. Species richness in the phytoplankton community was also reduced due to the narrowed annual range of salinity, which would eliminate the mid-high salinity species from the Mankyeong Bridge monitoring point. Similarly, species diversity was decreased with increased dominance of the phytoplankton community after the construction. Between the two summer seasons during the present study, species diversity was higher in 2007 than in 2006, which might indicate the early stage of a gradual stabilization in the ecosystem including the phytoplankton community at the monitoring station. The phytoplankton community thus needs to be monitored on a long-term basis to identify indirect signals that can be used to assess the stability of the ecosystem in the young Saemankeum Lake.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.4
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• pp.369-378
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• 2010

Microorganisms are key-role player for stabilization of landfill sites. In order to evaluate the availability of T-RFLP(Terminal Restriction Fragment Length Polymorphism) for monitoring microbial community variations during stabilization of landfill sites, the phylogenic diversity of microbial community in the leachate from 4 different full-scale landfills was characterized by T-RFLP based on bacterial 16S rDNA. Main population of microbial community analyzed by T-RFLP was significantly similar with that of microbial community analyzed by clone library analysis. The results of T-RFLP analysis for main population of microbial community in the leachate from landfills with different landfill structures, waste types and landfill ages showed apparently different microbial diversity and structures. Therefore, long-term monitoring of microbial community in leachate from landfill sites by using T-RFLP is expected to be available for evaluation of landfill stability.

• Geomechanics and Engineering
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• v.11 no.4
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• pp.471-492
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• 2016

Underground tunnelling is one of the sustainable construction methods which can facilitate the increasing passenger transportation in the urban areas and benefit the community in the long term. Tunnelling in various ground conditions requires careful consideration of the stability factor. This paper investigates three dimensional stability of a shallow circular tunnel in a layered soil. Upper bound theorem of limit analysis was utilised to solve the tunnel face stability problem. A three dimensional kinematic admissible failure mechanism was improved to model a layered soil and limiting assumptions of the previous studies were resolved. The study includes calculation of the minimum support pressure acting on the face of the excavation in closed-face excavations. The effects of the characteristics of the layers on the minimum support pressure were examined. It was found that the ratio of the thickness of cover layers particularly when a weak layer is overlying a stronger layer, has the most significant influence on the minimum tunnel support pressure. Comparisons have been made with the results of the numerical modelling using FLAC3D software. Results of the current study were in a remarkable agreement with those of numerical modelling.

• Korean Journal of Rural Living Science
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• v.7 no.2
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• pp.139-152
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• 1996

The objectives of this study are : (1) to measure the level of economic stress perception in Korean farm households. (2) to identify the effects of related variables such as socio-demographic variables and economic stability. The data from 505 farm households' wives was analyzed using statistical methods such as frequency, correlation, oneway ANOVA, lease significant difference test, and stepwise multiple regression. The major findings are as follows : The mean value of economic stress perception on the 505 wives was 33.5 points out of a possible 100. Among 3 subsectors, income stress perception had highest score. Socio- demographic variables such as family size, type of farm household, financial manager, debt, credit . grant assistant, wife's age, and educational level of the wife had a significant difference on the economic stress perception of wives in the ANOVA analysis. So did the objective and subjective evaluation of economic stability. As a result of multiple regression analysis, economic stability, debt presence, and wife age were verified explaining 23% of the variance of economic stress perception. Therefore, it can be said that farm wives had relatively high economic stress perception in the case of low economic stability, getting into debt and low age.

• Steel and Composite Structures
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• v.33 no.4
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• pp.551-568
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• 2019

This proposed project presents the bi-axial and uni-axial stability behavior of laminated composite plates based on an original three variable "refined" plate theory. The important "novelty" of this theory is that besides the inclusion of a cubic distribution of transverse shear deformations across the thickness of the structure, it treats only three variables such as conventional plate theory (CPT) instead five as in the well-known theory of "first shear deformation" (FSDT) and theory of "higher order shear deformation" (HSDT). A "shear correction coefficient" is therefore not employed in the current formulation. The computed results are compared with those of the CPT, FSDT and exact 3D elasticity theory. Good agreement is demonstrated and proved for the present results with those of "HSDT" and elasticity theory.

• The Korean Journal of Community Living Science
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• v.17 no.3
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• pp.43-53
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• 2006

In order to improve on the stability during the storage of Han-gwa, this study measured peroxide value, AOM test of ginseng and antioxidants added to Han-gwa. 1.2% of ginseng added to Han-gwa consists of moisture (3.37%), protein(1.30%), lipids (11.54%), carbohydrate(82.45%) and ash (1.34%). The hardness of Han-gwa was 257.7 for 1.2% of ginseng added to Han-gwa and 269.8 for Han-gwa without ginseng. The expansion coefficient of Han-gwa including 1.2% of ginseng was 12.9 magnification to Bandegi, indicating that it was inversely proportioned to the amount of ginseng. The induction period of the AOM test according to the concentration of ginseng in Han-gwa was extended to $0.53{\sim}0.83$ of magnification than the test of Han-gwa without ginseng. According to changes in AOM, acid value, peroxide value and thiobarbituric acid value of Han-gwa with various packing materials, PP multilayer film packing was the most effective material for storage of Han-gwa at 30C. 1.2% of ginseng added to Han-gwa and rosemary extract in a panel test was the most effective, and using PP multilayer film packing for Han-gwa was found to be the most useful method.

• The Korean Journal of Community Living Science
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• v.15 no.2
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• pp.179-187
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• 2004

The purpose of this study is to investigate the preservation of traditional sesame dasik when stored in different packaging material by comparing its physical and sensorial characteristics. The quality and sensory characteristics of sesame dasik that were evaluated were moisture content, water activity, number of microflora, texture profile, Hunter color different value, and sensory properties (color, chewiness, overall acceptability, etc) during the storage at 35\pm1^\circ{C}$ temperature and $73\pm{2%}$ relative humidity. And the packaging materials were paper boxes (coated 0.02mm thickness polyethylene film), plastic boxes, and oriented polypropylene laminated film. Traditional sesame dasik is made from sesame powder 100g, honey 25g, rice syrup 25g, and table salt 0.5g. During the storage period, the changes in water content and water activity of sesame dasik with different packaging material showed a slight decline. On the other hand, it increased in hardness, and "a" and "b" value of Hunter color difference during the storage. Texture profile analysis data change in hardness was the greatest after the third day in a paper box, and it was affected by the moisture content of dasik and the temperature and relative humidity of the air. Therefore plastic boxes or oriented polypropylene laminated film was found to be better suited than paper boxes for storing sesame dasik.

• Journal of Distribution Science
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• v.17 no.12
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• pp.23-32
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• 2019

Purpose As consumer awareness grows, the importance of CSR becomes even more important for long-term growth. In response to this current trend, the purpose of this study is to analyze the effect of CSR activities on business performance for logistics companies. Research design, data, and methodology - Between CSR activities and growth, there was a generally positive(+) relationships between activities such as donation and volunteerism and the growth of the enterprise. In terms of the relationship between environmental factors and growth, negative results were expressed. In case of profitability, improved welfare for workers has had a positive impact on corporate profitability. Results - With respect to stability, a high proportion of equity capital is not considered to be more active in SCR activities. Significant negative results were given between the minimum factors for entry, transportation, and noise generation factors and the ratio of liabilities, which are representative friction factors in the community. Conclusions - With respect to stability, a high proportion of equity capital is not considered to be more active in SCR activities. Significant negative results were given between the minimum factors for entry, transportation, and noise generation factors and the ratio of liabilities, which are representative friction factors in the community.

• Korean Journal of Social Welfare
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• v.44
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• pp.64-90
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• 2001

There has been a demand of changing service delivery system for social welfare services, and therefore changing is resource acquisition environment for community social welfare service organizations (CSWSOs). These phenomena are, however, not properly actualized through the CSWSOs. The discrepancy between environmental demand and organizational adaptation seems to result from our lack of understanding those organizations. Based on this understanding, several research problems have been formulated on resource acquisition behaviors of CSWSOs. Empirical data were gathered, and the final sample included 82 social welfare agencies of Pusan province and 122 top/high level agency administrators. The result of data analysis and their implications are as follows: (1) Most of CSWSOs prefer government grants to other financial resources, because government resources can give them more stability than others including private donations and user fees. (2) In order to induce changes in CSWSOs, their stability needs should be properly counted. (3) There is no enough evidence to prove that CSWSOs leaders' personal characteristics have contributed to the behavioral differences on financial resource acquisition among CSWSOs. Rather, there has been enough evidence to prove for influences by institutional environment factors. So, it is recommended that, in order to change behaviors of CSWSOs, the focus should be given to the proper control of those institutional environment factors.