• 한국환경생태학회지
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• 제11권2호
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• pp.160-165
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• 1997

본 연구는 강원도 오대산, 점봉산, 중왕산 지역의 신갈나무림을 대상으로 우점도 다양성 지수를 조사하였다. 신갈나무 군락은 종다양도 지수가 0.4~1.2, 종풍부도 지수가 2~11, 균재도 지수가 0.6~0.9로 어느 한 값에 치우치지 않는 것으로 나타나 비교적 안정된 상태의 것으로 판단된다. 종서열 중요치 곡선은 모든 군락에서 대수정규분포에 접근하고 있으며, 비교적 기울기가 완만하였다. 그리고 신갈나무-생강나무 군락의 기울기가 비교적 급하게 나타나 균등성이 낮았으며, 신갈나무-까치박달나무 군락의 종서열 중요치 곡선의 기울기가 완만하게 나타나 균등성이 높고 군락의 안정성이 클 것으로 판단된다.

• Ocean and Polar Research
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• 제31권1호
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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.

• 대한환경공학회지
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• 제32권4호
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• pp.369-378
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• 2010

폐기물매립장의 안정화에는 미생물이 중요한 역할을 수행한다. 폐기물매립장에서 미생물군집 변화 모니터링에 말단 제한절편다형성(Terminal Restriction Fragment Length Polymorphism; T-RFLP)법의 활용 가능성을 평가하고자 박테리아의 16S rDNA 서열에 기초한 T-RFLP법으로 4개의 폐기물매립장 내부에서 채취한 침출수의 미생물군집 구조를 조사하였다. T-RFLP법을 사용하여 해석한 침출수 내 우점 미생물군집 구조와 일반적으로 널리 사용되고 있는 16S rDNA 클론 해석법에 의한 우점 미생물군집구조는 유사하였다. 또한, T-RFLP법을 이용하여 폐기물매립장의 구조, 매립 폐기물 종류, 운영기간이 다른 폐기물매립장 침출수의 우점 미생물군집 구조가 서로 다르게 나타나는 것을 확인 할 수 있었다. 따라서 T-RFLP법을 사용하여 폐기물매립장 침출수내 미생물군집 구조를 장기적으로 모니터링 한다면 많은 비용과 시간이 소요되는 클론해석법의 반복적인 수행 없이도 비교적 간단하게 폐기물매립장의 안정화 정도를 평가할 수 있을 것으로 기대한다.

• Geomechanics and Engineering
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• 제11권4호
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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.

• 한국농촌생활과학회지
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• 제7권2호
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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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• 제33권4호
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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.

• 한국지역사회생활과학회지
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• 제17권3호
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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.

• 한국지역사회생활과학회지
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• 제15권2호
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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.

• 유통과학연구
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• 제17권12호
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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.

• 한국사회복지학
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• 제44권
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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.