• Geomechanics and Engineering
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• v.3 no.3
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• pp.233-254
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• 2011

The consolidation behavior of Sri Lankan peaty clay is analyzed using an elasto-viscoplastic model. The model can describe the secondary compression behavior as a continuous process and it can also account for the effect of structural degradation on the consolidation analysis. The analysis takes into account all the main features involved in the process of peat consolidation, namely, finite strain, variable permeability, and the secondary compression. The material parameters required for the analysis and the procedures to evaluate them, using both standard laboratory and field tests, are explained. Initially, the model performance is assessed by comparing the predicted and the observed peat consolidation behavior under laboratory conditions. The results indicate that the model is capable of predicting the observed creep settlements and the effect of layer thickness on the settlement analysis of peaty clay. Then, the model is applied to predict the consolidation behavior of peaty clay under different field conditions. In this context, firstly, the one-dimensional field consolidation of peaty clay, brought about by the construction of compacted earth fill, is predicted. Then, the two-dimensional peat foundation response upon embankment loading is simulated. A good agreement is seen in the comparison of the predicted results with the field observations.

• Korean Journal of Childcare and Education
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• v.12 no.3
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• pp.41-60
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• 2016

The purpose of this study was to examine differences in multicultural early childhood teaching activities according to the general characteristics of early childhood teachers, to analyze the relationships and effects of early childhood teachers' happiness, variables of attitudes toward the teaching profession, and variables of multicultural teaching, and ultimately to identify variables related to early childhood teachers that explain multicultural early childhood teaching activities. For this study, 270 teachers in charge of young children from multicultural families at early childhood education institutions were sampled. When the 'age' variable, which might affect multicultural teaching activities, was excluded and the relationships among early childhood teachers' variables as independent variables were analyzed, happiness and obsessive passion were found to have an effect on multicultural teaching activities. These findings suggest that early childhood teachers' happiness and passion for teaching needs to be enhanced as an effort to set the direction of multicultural education fit for the characteristics of Korea in the field of early childhood education, where the foundation of culture is laid and prejudices are easily formed.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.4
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• pp.315-322
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• 2015

In this paper, the theory of rectangular plate on the elastic foundation is used to get the relation equation between the effective Young’s modulus and the ice sheet deflection by applying the characteristic length concept, since the model ice sheet is rectangular shape in KRISO (Korea Research Institute for Ships and Ocean Engineering) ice basin. The obtained relation equation is equal to that of using the circular plate theory. A device is made and used to measure the deflection of ice plate using LVDT (Linear Variable Differential Transformer) for several loading cases and the procedure of experiments measuring the deflection used for getting the Young’s modulus is explained. In addition, the flexural strength value obtained through flexural strength experiments is compared with that of finite element analysis using the obtained effective Young’s modulus. Also, a nonlinear FEA (Finite Element Analysis) of cantilever ice beam is done with eroding effect and LS-DYNA result shows the fracture of brittle ice under 1 mm/s velocity load.

• International Journal of Human Ecology
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• v.1 no.1
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• pp.1-14
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• 2000

Parental satisfaction is the foundation of a happy family. It is a key factor in overall life satisfaction and also a critical variable in the development of children, and thus an education program aimed at parental satisfaction improvement is needed. This study attempts to determine basic elements of parental satisfaction that could enable better parental education programs. To accomplish this, mother's parental satisfaction and factors related to it were examined. The subjects were 641 mothers of primary school and middle school students aged 10, 12, and 14 residing in Seoul, Pohang and Kwangyang. Structured self-administered questionnaires were used to ascertain mothers' parental role satisfaction, mothers' role values, children related variables, mother related variables, father related variables, and home environment variables. The findings indicate that the variables related to parental satisfaction are multi-dimensional, that mothers' parental satisfaction can be improved by other family member's effort, and that a family's external characteristics are less important than its internal characteristics. These results imply that it is essential to include the characteristics of the family system when designing parental education programs. Furthermore, the role of specific family members, namely the husband, should be expanded in more supportive ways in Korean families to improve mothers parental satisfaction.

• Smart Structures and Systems
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• v.18 no.5
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• pp.1029-1062
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• 2016

In this research, the nonlinear free vibration analysis of boron-nitride micro ribbon (BNMR) on the Pasternak elastic foundation under electrical, mechanical and thermal loadings using modified strain gradient theory (MSGT) is studied. Employing the von $K{\acute{a}}rm{\acute{a}}n$ nonlinear geometry theory, the nonlinear equations of motion for the graphene micro ribbon (GMR) using Euler-Bernoulli beam model with considering attached mass and size effects based on Hamilton's principle is obtained. These equations are converted into the nonlinear ordinary differential equations by elimination of the time variable using Kantorovich time-averaging method. To determine nonlinear frequency of GMR under various boundary conditions, and considering mass effect, differential quadrature element method (DQEM) is used. Based on modified strain MSGT, the results of the current model are compared with the obtained results by classical and modified couple stress theories (CT and MCST). Furthermore, the effect of various parameters such as material length scale parameter, attached mass, temperature change, piezoelectric coefficient, two parameters of elastic foundations on the natural frequencies of BNMR is investigated. The results show that for all boundary conditions, by increasing the mass intensity in a fixed position, the linear and nonlinear natural frequency of the GMR reduces. In addition, with increasing of material length scale parameter, the frequency ratio decreases. This results can be used to design and control nano/micro devices and nano electronics to avoid resonance phenomenon.

• Journal of Korean Library and Information Science Society
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• v.29
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• pp.105-140
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• 1998

This is a way of establishing the information sovereignty in the industrial knowledge of society. The occurrence of the industrial knowledge of society builds knowledge and information as digital system. Digitalized knowledge and information has some characteristics of which the information should be light and variable, so that it can be transmitted rapidly. At this moment, if information super highway is built, and the digitalized information of the advanced information country comes to us, we are to get easily information dependence unless we are ready. Nowadays, our country is accepting the knowledge and information of the advanced information countries without filtering it properly. What is the reason? This means that we are lack of traditional knowledge resourses as the foundation of digital system. This paper deals with (1) the historical reason of the lackness of the traditional knowledge resourses, (2) the aspect of the consumer culture about knowledge and information, and (3) the aspect of the production culture about the knowledge and information. In order to overcome the information dependence, in this paper, we should change both production and consumption of our knowledge and information into a new pattern, establish the seed knowledge resourses, and build libraries everywhere we can use easily. For this case study, this paper takes examples of maeul (which may mean traditional villiage in Korea.) libraries on Changwon City.

• Molecules and Cells
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• v.26 no.3
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• pp.319-322
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• 2008

Little is known about the chromosomal variability and polymorphism existing in mitotic chromosomes of Citrus, mainly due to lack of reliable chromosomal markers and small chromosome size. To test the hypothesis of chromosomal polymorphism and provide the foundation of the genome organization in the Citrus cultivars, we have developed molecular cytogenetic markers for 13 Citrus species collected from Jeju island, Korea. In this study, we demonstrated that the chromosomal locations of cytogenetic markers are quite variable and extremely polymorphic, in contrast to the previous studies. The data obtained in this study will be of utmost importance in cytological systematics and karyotyping of the Citrus species.

• Geomechanics and Engineering
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• v.10 no.2
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• pp.155-174
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• 2016

A total of 104 laboratory model tests on a square footing subjected to eccentrically inclined loads supported by sand reinforced with randomly distributed polypropylene fibers were conducted in order to compare the results with those obtained from unreinforced sand and with each other. For conducting the model tests, uniform sand was compacted in a test box at one particular relative density of compaction. The effect of percentage of reinforcement used, thickness of the reinforced layer, angle of inclination of load to vertical and eccentricity of load applied on various prominent factors such as ultimate load, vertical settlement, horizontal deformation and tilt were investigated. An improvement in ultimate load, vertical settlement, horizontal deformation and tilt of foundation was observed with an increase in the percentage of fibers used and thickness of reinforced sand layer under different inclinations and eccentricities of load. A statistical model using non-linear regression analysis based on present experimental data for predicting the vertical settlement ($s_p$), horizontal deformation ($hd_p$) and tilt ($t_p$) of square footing on reinforced sand at any load applied was done where the dependent variable was predicted settlement ($s_p$), horizontal deformation ($hd_p$) and tilt ($t_p$) respectively.

• Environmental Engineering Research
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• v.21 no.1
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• pp.91-98
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• 2016

Along with China's increasing share in global total $CO_2$ emissions, there is a necessity for China to shoulder large emission-mitigating responsibility. The appropriate allocation of $CO_2$ emission quotas can build up a solid foundation for future emissions trading. In views of originality, an optimized approach to determine $CO_2$ emissions allocation efficiency based on the zero sum gains data envelopment analysis (ZSG-DEA) method is proposed. This paper uses a non-radial ZSG-DEA model to allocate $CO_2$ emissions between different Chinese provinces by 2020 and treats $CO_2$ as the undesirable output variable. Through the calculation of efficiency allocation amounts of provincial $CO_2$ emissions, all provinces are on the ZSG-DEA efficiency frontier. The allocation results indicate that the cumulative optimal amounts of $CO_2$ emissions in 2020 were higher than the actual amounts in 13 provinces, and lower in other 17 provinces, and show that different provinces have to shoulder different mitigation burdens in terms of emission reduction.

• Journal of the Korean housing association
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• v.22 no.3
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• pp.113-122
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• 2011

This study aimed to develop AI- (Artificial Intelligence) based thermal control logics and test their performance for identifying the optimal thermal control method in buildings. For this objective, a conventional Two-Position On/Off logic and two AI-based variable logics, which applied ANN (Artificial Neural Network) and ANFIS (Adaptive Neuro-Fuzzy Inference System), have developed. Performance of each logic was tested in a typical two-story residential building in U.S.A. using the computer simulation incorporating MATLAB and IBPT (International Building Physics Toolbox). In the analysis of the test results, AI-based control logic presented the advanced thermal comfort with stability compared to the conventional logic while they did not show significant energy saving effects. In conclusion, the predictive and adaptive AI-based control logics have a potential to maintain interior air temperature more comfortably, and the findings in this study could be a solid foundation for identifying the optimal thermal control method in buildings.