• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.1
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• pp.38-44
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• 2007

Using the mathematical model suggested by Bennet et al.(1992), the reflection and transmission coefficients by a circular pile breakwater has been investigated in the framework of potential theory. Flow separation due to sudden contraction and expansion is generated and is the main cause of significant energy loss. Therefore, evaluation of exact energy loss coefficient is critical to enhance the reliability of mathematical model. To obtain the energy loss coefficient, 2-dimensional turbulent flow is analyzed using the FLUENT commercial code. The energy loss coefficient can be obtained from the pressure difference between upstream and downstream. Energy loss coefficient is the function of porosity and the relation equation between them is suggested throughout the curve fitting processing. To validated the suggested relation, comparison between the analytical results and the experimental results is made for four different porosities with good agreement.

• Journal of the Korean Society of School Health
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• v.28 no.3
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• pp.139-149
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• 2015

Purpose: This study aims to analyze the factors affecting the agenda-setting process and the formation process of school-based mental health policies by applying a policy stream model. Methods: For this purpose, Kingdon's policy stream model was used as the analytical framework. Results: First, when establishing a school-based mental health policy, the agenda was set going through unpredictable and nonlinear changes. Second, for the school-based mental health policy to be selected onto the agenda and to be developed and implemented as an actual policy, the role of policy makers was considered most important in the process. Third, the policy window for school-based mental health policy was closed around the year 2013. Finally, an analysis of the school-based mental health policy stream identified two key features. One is that the school-based mental health policy first emerged when school violence prevention policy expanded its scope into relevant neighboring policies. The other is that the school-based mental health policy has taken shape through a linear decision-making process (being put on the government's agenda, searching for an alternative, selection, and implementation) during the policy implementation period after it has been selected as an alternative policy. Conclusion: Conclusions can be summed up as follows. The school-based mental health policy needs continuous development and improvement in case the window for the policy may open in the coming future. The government's support is needed to draw policy makers' interest and participation who play the biggest role in establishing policies.

• Journal of Science and Technology Studies
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• v.3 no.2 s.6
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• pp.1-27
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• 2003

Complexity paradigm is a scientific amalgam that aims to unite a range of theoretical perspectives and research agendas across natural and social sciences. Proponents of complexity paradigm lay claims to an increasing number of areas of study, including artificial life, interpersonal networks, internal/international patterning of organizations, mapping of cyberspace, etc. All of those can be subsumed under the title, 'complexity turn.' Owing to the idea of open system, complexity paradigm has developed a number of new concepts/themes/perspectives that help to account for the complex mechanism of living and non-living creatures. A complex system comprises a number of properties such as disequilibrium, nonlinearity, dissipative structure, self-organization fractal geometry, autopoiesis, coevolution. Following a brief introduction to theoretical development, those properties are succinctly discussed. The complexity turn has provided a wealth of insights that enable to analyze system operations of any kind. It contributes a lot to illuminating the working of social system as well. The most remarkable attempt may be Niklas Luhmann's 'neofunctional system theory.' Merits and shortcomings of complexity paradigm were examined and its future prospect were assessed with the conclusion that complexity paradigm would continue to be useful both as effective transdisciplinary framework and powerful analytical tool.

• Korean Journal of Social Welfare Studies
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• no.39
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• pp.189-219
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• 2008

The purpose of this article is to examine the dynamics of pension insurance policy-making and policy outputs under the developmental state of Korea, by analysing the first attempt to establish the national pension scheme in the early 1970s. To the aim, this article formulated the comprehensive analytical framework from the viewpoint of process-oriented perspective, linking policy-making dynamics with the policy context as an external constraint and policy output as a result of policy-making. Policy context was explored in terms of three variables of politics, civil society and economy, whilst policy-making and policy network dynamics were examined by employing the following variables: i) initiators, motivation and triggering devices, ii) number of participants and key players, iii) participants' interests, iv) major conflicting parties and key differences of allegation, and v) interactions between participants. Policy outputs were analysed by looking into the mainly reflected interests and the change of intended policies.

• Journal of the Korean School Mathematics Society
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• v.24 no.2
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• pp.191-216
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• 2021

This study analyzes how statistical literacy is implemented along with the statistical problem-solving process as described in the Statistical Estimation Unit of the textbook by the 2015 revised mathematics curriculum. The analytical framework was developed from the literature, and consists of 'context', 'variability', 'mathematical and statistical knowledge', 'using of technological instruments', 'critical attitude', and 'communication'. From the perspective of the statistical problem-solving process, the analysis revealed that many tasks equivalent to 'Analyzing Data' but lacked tasks related to 'Interpreting Results' and 'Formulating Questions'. As a result of analyzing the reflection of each element of statistical literacy, 'mathematical and statistical knowledge' was the most common task, but 'critical attitude' and 'using of technological instruments' were rarely dealt with. Based on the results of this textbook analysis, it was intended to provide implications for improving the curriculum and the development of textbooks for the growth of statistical literacy.

• Korean Journal of Family Social Work
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• no.58
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• pp.151-179
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• 2017

The purpose of this study was to evaluate the communication enhancement program through Social Network Service(SNS) of older adults in the community. This program was mainly designed for improving self-efficacy of older adults and enhancing their communication in the community by using SNS. This program was composed of several sub-programs; understanding the value of communication, meeting with SNS users, SNS education and practice, having activities with SNS, promoting SNS, holding public rehearsals and starting ceremony, and having off-line meeting. This study applied analytical framework based on logic model of systems theory, collected data from the subject group, and evaluated the sub-programs on dimensions of process and outcome. The results showed that this program has an effect on improving self-efficacy through participating SNS activities, enhancing communication through boosting SNS, creating new culture for older adults, and changing attitudes between generations. Based on these results, the practical guidelines for expanding the communication enhancement program through SNS, leading by older adults in the community, were suggested.

• Journal of the Korea Computer Graphics Society
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• v.25 no.3
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• pp.133-142
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• 2019

In physics-based character animation, trajectory optimization has been widely adopted for automatic motion synthesis, through the prediction of an optimal sequence of future states of the character based on its system dynamics model. In general, the system dynamics model is neither in a closed form nor differentiable when it handles the contact dynamics between a character and the environment with rigid body collisions. Employing smoothed contact dynamics, researchers have suggested efficient trajectory optimization techniques based on numerical differentiation of the resulting system dynamics. However, the numerical derivative of the system dynamics model could be inaccurate unlike its analytical counterpart, which may affect the stability of trajectory optimization. In this paper, we propose a novel method to derive the closed-form derivative for the system dynamics by properly approximating the contact model. Based on the resulting derivatives of the system dynamics model, we also present a model predictive control (MPC)-based motion synthesis framework to robustly control the motion of a biped character according to on-line user input without any example motion data.

• Journal of Digital Convergence
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• v.17 no.8
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• pp.47-60
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• 2019

The purpose of this study is to explore the overall structural relationship between the statutory provisions of nuclear energy legislation and to identify the coherence of the nuclear law system using social network analysis. In particular, we analyze the legal structure of the "Nuclear Safety Act", which plays a central role in nuclear safety regulation, to examine the key provisions in legal network structure of Nuclear Safety Act. Therefore, we found the structural problems of the nuclear legal system and suggest the legislative improvement plan for reducing excessive legislative activity and determining the need for legal amendments in nuclear safety management and regulation. This study is expected to provide a analytical framework for making legal system of further policy in other science and technology industries as well as nuclear energy related industries.

• Computers and Concrete
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• v.27 no.4
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• pp.319-332
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• 2021

The performance of gene expression programming (GEP) in predicting the compressive strength of bacteria-incorporated geopolymer concrete (GPC) was examined in this study. Ground-granulated blast-furnace slag (GGBS), new bacterial strains, fly ash (FA), silica fume (SF), metakaolin (MK), and manufactured sand were used as ingredients in the concrete mixture. For the geopolymer preparation, an 8 M sodium hydroxide (NaOH) solution was used, and the ambient curing temperature (28℃) was maintained for all mixtures. The ratio of sodium silicate (Na2SiO3) to NaOH was 2.33, and the ratio of alkaline liquid to binder was 0.35. Based on experimental data collected from the literature, an evolutionary-based algorithm (GEP) was proposed to develop new predictive models for estimating the compressive strength of GPC containing bacteria. Data were classified into training and testing sets to obtain a closed-form solution using GEP. Independent variables for the model were the constituent materials of GPC, such as FA, MK, SF, and Bacillus bacteria. A total of six GEP formulations were developed for predicting the compressive strength of bacteria-incorporated GPC obtained at 1, 3, 7, 28, 56, and 90 days of curing. 80% and 20% of the data were used for training and testing the models, respectively. R2 values in the range of 0.9747 and 0.9950 (including train and test dataset) were obtained for the concrete samples, which showed that GEP can be used to predict the compressive strength of GPC containing bacteria with minimal error. Moreover, the GEP models were in good agreement with the experimental datasets and were robust and reliable. The models developed could serve as a tool for concrete constructors using geopolymers within the framework of this research.

• Journal of The Korean Association For Science Education
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• v.41 no.1
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• pp.19-32
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• 2021

This study aims to analyze the visual modeling process of pre-service elementary teachers on the reflection of light. The analytical framework was developed from three aspects; coherence, correspondence, and commensurability of the modeling thinking proposed by Halloun (2004). 20 pre-service elementary teachers participated and were randomly paired to observe the reflection of light. They were asked to construct the visual model individually at first and then collaboratively. Comparing personal and cooperative models, the level of correspondence and commensurability in some groups has increased, despite the lack of special educational treatment. In addition, three main features were found in their reasoning process. First, the level of commensurability to apply the law of reflection continued to change fluidly depending on the circumstances and often the verbal and visual explanations did not match. Second, in the process of visual modeling, correspondence was often given priority over commensurability and coherence. Third, in a situation where correspondence and commensurability are at odds with each other, participants resolved this conflict and developed reasoning through review and revision of the auxiliary hypothesis. Several implications have been discussed for effectively guiding visual modeling activities.