• The Korea Journal of Herbology
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• v.23 no.1
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• pp.117-125
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• 2008

Objectives : This study was to verify the Attributive Channel theory of herbal medicine. Methods : [$^{131}I$]iodohesperetin was synthesized, separated, and refined from hesperetin, the major component of Citrus species, followed by observing the biodistribution in an organism of C57 BL/6 mice with and without Lewis Lung Carcinoma. Results : Iodohesperetin 27.5 mg was obtained through column cliromatography after a reaction with 50 mg of Hesperitin and 8 mg of Nal. The radiochemical yield of [$^{131}I$]iodohesperetin synthesis was 25 % when checked with Radio TLC chromatography. [131I]iodohesperetin was most largely distributed in the stomach, lung and liver of C57BL/6 mouse. The highest %ID/g in stomach was 40 min, in lung and liver was 20 min after injection. The % ID/g of tumor tissue was comparable with that of blood. Conclusions : The fact that [$^{131}I$]iodocurcumin was most largely distributed in the stomach, lung and liver was related with the Attributive Channel theory. And there was no significant finding related to tumor cells.

• Journal of The Korean Association For Science Education
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• v.44 no.1
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• pp.105-117
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• 2024

The purpose of this study was to explore changes in elementary teachers' modeling pPCK (personal PCK) resulting from knowledge exchange within the realms of PCK described in the Refined Consensus Model (hereafter RCM). For this purpose, a professional learning community (hereafter PLC) was established for three elementary school teachers to facilitate knowledge exchange specifically focused on science modeling instructions. The study then analyzed the CoRe (content representations) written by the research participants twice to explore any changes in modeling pPCK (personal PCK). In addition, the discourse shared by the participants in the PLC and the data from the in-depth interviews were also analyzed using grounded theory research methods. The results of the study showed that there was no significant change in knowledge of the science curriculum in elementary teachers' modeling pPCK, but there were changes in orientations toward teaching science, knowledge of students' understanding in science, knowledge of instructional strategies and representations, and knowledge of assessment of science learning. Furthermore, the analysis of PLC discourse and in-depth interviews showed that modeling instructions reflection (ePCK; enacted PCK) and educational research-based modeling cPCK (collective PCK) influenced these changes in teachers' modeling pPCK. Accordingly, this study suggests recommendations for pedagogical approaches aimed at improving teachers' modeling PCK.

• (The)Study of the Eastern Classic
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• no.37
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• pp.249-278
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• 2009

Zhu-zi(朱子) represented the study of The Book of Odes in Song dynasty and Dai-zhen(戴震) was The Book of Odes researcher representing Wan-pai(a kind of party) in Qing dynasty. Especially Dai-zhen took critical position of Zhu-xi. Comparing Zhu-zi with Dai-zhen in the aspect of The Book of Odes interpretation, this thesis intends to review the difference and the reason of both interpretations. Especially this thesis compares Zhu-zi's interpretation with Dai-zhen's about thirty poems Zhu-zi considered filthy poetry, investigating the differences of their interpretation. Regarding the poetry Zhu-zi considered filthy as refined satire, Dai-zhen had a negative position about Zhu-zi's theory of filthy poetry. As Zhu-zi interpreted the poetry in the first person on the literary view in the time when he interpreted the lyrics in the Feng-shi, he regarded the purpose and the usefulness of poetry as feeling of words. But as Dai-zhen interpreted the poetry in the third person under a Confucian classic view, he regarded the purpose and the usefulness of poetry as refined satire. In brief, that is to say that Zhu-zi made literary interpretations of feeling of words but Dai-zhen made Confucian classic interpretations of 'Si-wu-xie'(思無邪). These two men's differences about interpretation of The Book of Odes have much importance on the historical aspects of The Book of Odes. So to speak, Dai-zhen had bibliographical approach and described the meaning of poetry objectively, following Mao-shi(毛詩) theory about the interpretation of meaning of poetry, criticizing Zhu-zi's literarary view. Dai-zhen's interpretation of The Book of Odes mentioned Above was made from long vital power of Mao-shi theory and a Confucian classic method. Considering the historical stream of Zhu-zi and Dai-zhen's interpreting The Book of Odes, The Book of Odes will be interpreted and analyzed from the various views in the future.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.5
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• pp.553-561
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• 2015

The exponential and power law functionally graded material(FGM) theory is reformulated considering the refined shear and normal deformation theory. This theory has ability to capture the both normal deformation effect and exponential and power law function in terms of the volume fraction of the constituents for material properties through the plate thickness. Navier's method has been used to solve the governing equations for all edges simply supported plates on Pasternak elastic foundation. Numerical solutions of vibration analysis of FGM plates are presented using this theory to illustrate the effects of power law index and 3-D theory of exponential and power law function on natural frequency. The relations between 3-D and 2-D higher-order shear deformation theory are discussed by numerical results. Further, effects of (i) power law index, (ii) side-to-thickness ratio, and (iii) elastic foundation parameter on nondimensional natural frequency are studied. To validate the present solutions, the reference solutions are discussed.

• Structural Engineering and Mechanics
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• v.85 no.1
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• pp.1-14
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• 2023

The use of functionally graded materials in applications involving severe thermal gradients is quickly gaining acceptance in the composite mechanics community, the aerospace and aircraft industry. In the present study, a refined sandwich plate model is applied to study the free vibration analysis of porous functionally graded material (FGM) sandwich plates with various distribution rate of porosity. Two types of common FG sandwich plates are considered. The first sandwich plate is composed of two FG material (FGM) face sheets and a homogeneous ceramic or metal core. The second one consists of two homogeneous fully metal and ceramic face sheets at the top and bottom, respectively, and a FGM core. The displacement field of the present theory is chosen based on nonlinear variations in the in-plane displacements through the thickness of the sandwich plate. The number of unknowns and equations of motion of the present theory is reduced and hence makes them simple to use. In the analysis, the equation of motion for simply supported sandwich plates is obtained using Hamilton's principle. In order to present the effect of the variation of the porosity distribution on the dynamic behavior of the FGM sandwich plates, new mixtures are proposed which take into account different rate of porosity distribution between the ceramic and the metal. The present method is applicable to study the dynamic behavior of FGM plates and sandwich plates. The frequencies of two kinds of FGM sandwich structures are analyzed and discussed. Several numerical results have been compared with the ones available in the literature.

• Journal of the Korean Society for Railway
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• v.12 no.4
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• pp.472-480
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• 2009

The stability analysis for CWR is difficult in the theory itself because both geometric and material nonlinearity should be considered. Also the analysis results are varied according to the loading history. In contrast to the complexity in the theory, the analysis results for CWR on the railway bridges are quite simple and can be predicted because of a small buckling effect and its negligible nonlinearity. In this study, refined nonlinear analysis methods for the stability analysis of CWR on the railway bridges were developed which consider only material nonlinearity beeause the effects of geometric nonlinearity are nominal. In this study, the analysis results can be found within limited number of iterations with idealized linear force-displacement relationship. From the analysis result comparisons, it was found that the stability analysis for CWR on the railway bridges can be performed effectively by this method.

• Korean Journal of Community Nutrition
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• v.28 no.6
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• pp.495-508
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• 2023

Objectives: This study aimed to develop a campus-based intervention program to enhance food literacy (FL) among university students. Methods: In the initial phase, we conducted a literature review of FL intervention studies and held in-depth interviews with university students to identify facilitators and barriers to improving and practicing FL. Expert counseling sessions were conducted with nutrition education, marketing, and service design professionals. The results of this phase led to the creation of an initial curriculum draft. In the second phase, a follow-up survey was conducted with young adults to assess the acceptability of the developed curriculum. After the follow-up survey, additional meetings were conducted with the aforementioned experts, and the curriculum was further refined based on their input. Results: An 11-week FL intervention program was devised using constructs from the Social Cognitive Theory. The weekly curriculum consisted of 90-min theory-based and 90-min hands-on experience sessions. Three primary aspects of FL were covered: nutrition and food safety, cultural and relational dimensions, and socio-ecological aspects. Program highlights included cooking sessions for crafting traditional Korean desserts, lectures on animal welfare, insights into zero-waste practices, and communal eating experiences. Based on the study team's previous research, the program also addressed mindful eating, helping participants understand the relationship with their eating habits, and providing strategies to manage negative emotions without resorting to food. Yoga sessions and local farm visits were incorporated into the curriculum to promote holistic well-being. Conclusions: This study elucidated the comprehensive process of creating a campus-based curriculum to enhance FL among university students, a group particularly susceptible to problematic eating behaviors and low FL levels. The developed program can serve as a blueprint for adaptation to other campuses seeking to bolster students' FL.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.5199-5206
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• 2010

In this paper, we investigate the buckling analysis of laminated composite plates, using a improved assumed natural strain shell element. In order to overcome membrane and shear locking phenomena, the assumed natural strain method is used. The eigenvalues of the laminated composite plates are calculated by varying the width-thickness ratio and angle of fiber. To improve an shell element for buckling analysis, the new combination of sampling points for assumed natural strain method was applied and the refined first-order shear deformation theory which allows the shear deformation without shear correction factor. In order to validate the present solutions, the reference solutions are used and discussed. The results of laminated composite plates under the in-plane shear loading may be the benchmark test for the buckling analysis.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.2
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• pp.11-20
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• 1993

Nonlinear inelastic behavior of an HP saddle shell has been examined by a finite element computer program developed on a Cray Y-MP. The mesh convergence is studied using three progressively refined finite element mesh models, $16{\times}16$, $32{\times}32$ and $64{\times}64$, for the elastic and inelastic analyses. It is shown that the $32{\times}32$ mesh model gives a solution that is very close to that given by the $64{\times}64$ mesh model, thus, showing a convergence. The inelastic analysis shows that the shell has a tremendous capacity to redistribute the stresses. At the ultimate, the concrete cracks and the reinforcement yieldings are spread out all over the shell, indicating that the stress distribution in the shell is approaching that given by the classical membrane theory. The present computer program provides a very useful tool for evaluating the nonlinear ultimate behavior of concrete shells during the design process.

• Composites Research
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• v.36 no.2
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• pp.117-125
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• 2023

This paper proposes a new finite element formulation based on enhanced first-order shear deformation theory including the transverse normal strain effect via the mixed formulation (EFSDTM-TN) for the effective thermo-mechanical analysis of laminated composite structures. The main objective of the EFSDTM-TN is to provide an accurate and efficient solution in describing the thermo-mechanical behavior of laminated composite structures by systematically establishing the relationship between two independent fields (displacement and transverse stress fields) via the mixed formulation. Another key feature is to consider the thermal strain effect without additional unknown variables by introducing a refined transverse displacement field. In the finite element formulation, an eight-node isoparametric plate element is newly developed to implement the advantage of the EFSDTM-TN. Numerical solutions for the thermo-mechanical behavior of laminated composite structures are compared with those available in the open literature to demonstrate the numerical performance of the proposed finite element model.