• Bulletin of the Korean Chemical Society
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• v.29 no.12
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• pp.2434-2440
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• 2008

The effect of sodium (Na) promotion was studied in the biphenol (BP) hydrogenation using various Pd/C catalysts. Different amounts of sodium metal were used for promotion with Pd/C and their effects on BP hydrogenation were observed. The promotion order was changed to compare the effect of the position of the promoter in relation to the palladium (Pd) metal on the catalytic activity and yield of the final product, bicyclohexyl-4,4'-diol (BHD). Pd/C catalysts prepared from different methods were also sodium-promoted and the changes of the reaction pathway according to the type of promoted Pd/C catalyst were compared.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.04a
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• pp.279-283
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• 2004

Thermal postbuckling and vibration analyses of functionally graded plates (FG plates) are performed. The nonlinear finite element equation based on the first-order shear deformation plate theory is formulated for the FG plate. The von Karman strain-displacement relation is used to account for the thermal large deflection. The incremental method considering the effect of the initial deflection and the initial stress is adopted for temperature-dependent material properties of functionally graded materials. The numerical result shows characteristics of the thermal postbuckling and vibration of FG plates in the pre- and post- buckled regions.

• Journal of the Korean Society of Earth Science Education
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• v.10 no.1
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• pp.38-49
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• 2017

The purpose of this study was to find out how pre-service teachers who have gone through training have thought about teaching practice. Specifically, I analyzed the relationship between college curriculum and teaching practice, and what they had felt in teaching practice. The study included 20 third grade students in teacher's college. The results of this study were as follows: First, it was found that the content knowledge and the pedagogical knowledge of the subjects taught at the university were helpful for the teaching practice. Second, they were thought that teaching practice would be helpful just to watch the class. And pre-service teachers felt that class demonstration was a necessary part of becoming a teacher. Third, pre-service teachers said that it is necessary to have a lecture in the university that can have opportunity for class demonstration for teaching practice. And also they wanted to open a lecture to learn various teaching techniques and the newest teaching methods. Fourth, pre-service teachers said that it is important to form relationships with students in order to complete the lessons through the teaching practice. And they said that they felt that the education scene was more powerful and harder than they thought. In addition, they said that through this exercise, it became a moment to feel the importance of thorough preparation and experience. In this way, teaching practice is an essential process for pre-service teachers to become teachers and it can be seen that they have many influences. Based on these results, it is necessary to review and revise the curriculum of the training colleges in relation to the teaching practice.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7701-7705
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• 2015

Background: Thyroid hormones (TH) are regulated by the hypothalamic-pituitary axis, which plays an important role in cell growth, differentiation, development and other aspects of metabolism. It is believed that an active hypothalamic-pituitary axis increases the susceptibility of thyroid dysfunction during systemic chemotherapy. In order to investigate the relation between thyroid function and chemotherapy the present study was designed to investigate TH in breast cancer patients receiving at least three cycles of chemotherapy. The levels of TH were measured at the baseline and before each cycle of chemotherapy. Materials and Methods: Blood samples for estimation of TH levels were collected from 80 (pre-menopausal-40; post-menopausal-40) breast cancer patients just before they were undergoing - $1^{st}$, $2^{nd}$, $3^{rd}$ and $4^{th}$ cycle of chemotherapy. The serum was separated and $T_3$, $T_4$ and TSH levels were determined by chemiluminescence method. Results: $T_3$ and $T_4$ were found significantly decreased and TSH was found significantly increased after $1^{st}$ (p<0.001), $2^{nd}$ (p<0.0001) and $3^{rd}$ cycle of chemotherapy (p<0.0001). The variation of $T_3$ levels (decreased) and TSH levels (increased) was found more in post-menopausal (p<0.0001) women then in pre-menopausal women after $3^{rd}$ cycle of chemotherapy as compared to baseline (p<0.001). Conclusions: TH were remarkably altered after each cycle of chemotherapy leading to decline in thyroid function of breast cancer patients. Further, the results also indicated that post-menopausal women were more prone towards decline in thyroid function then pre-menopausal women. The present study proposes the monitoring of TH after each cycle of chemotherapy in breast cancer patients.

• Journal of Plant Biology
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• v.17 no.1
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• pp.15-21
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• 1974

The most commonly grown economical and flue-cured tobacco cultivar Yellow Special A was used in pot-culture tests in order to study Ethrel (2-chloroethyl phosponic acid) effects on accelerating maturity of tobacco leaves in relation to the most adequate level of the chemical useful for field growing, nitrogen level in soil for the most pronounced response, and the most suitable spray period during the growth stages of pre-, post- and topping periods. The following conclusions, thus, were obtained from the present studies; 1. 500ppm Ethrel spray was reconfirmed to be adequate in the practical applications, although the extent of yellow-ripening of tobacco leaves was increased as the Ethrel level increased. The highest leevel treated resulted in causing chemically damaged lesions on leaves and early defoliation. 2. Ethrel-treated leaves showed deeper yellowish tinge to them than those without treatment, while different levels of the chemcial had less influence on the tinge. 3. An adequate level of nitrogen supply to plants favored the Ethrel response, whereas either very low or high level of nitrogen in the soil lowered the chemical effect on accelerating the yellow-ripening. When carbohydrates versus total nitrogen ratio became relatively high, the condition brought out some outstanding Ethrel effects. 4. Chlorophyll level of leaves increased as soil applications of nitrogen level increased, and that also increased carotenoid level of the tobacco leaves. Ethrel-treated leaves showed deeper orange tinge than those without treatment, while the highest level of nitrogen application showed the deepest orange tinge to tobacco leaves. 5. Pre-topping treatment (12 days before topping and flowering) resulted in almost no Ethrel response, and that treatment right on the day of topping, showed response of yellow-leaf ripening at nearly bottom-half leaves of a tobacco plant. The post-topping treatment (12 days after topping) made plants showing full response of Ethrel from bottom to the top leaves of tobacco plant in accelerating the leaf maturity. 6. The extent of Ethrel responses on accelerating yellow-ripening of tobacco leaves was discussed for the modifying influences brought about by certain environmental factors. Discussions were also made about the possible practical applications (particularly for pre-rice planting) and quality difference that may be caused by such growth environments.

• Journal of Science Education
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• v.44 no.1
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• pp.1-14
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• 2020

In this study, we analyzed the written and drawn explanations of thirty elementary school pre-service teachers in order to examine their perception on the seasonal length of day and night. The main findings are as follows: First, pre-service teachers used the most common term in the description of the texts, such as meridian altitude, axis of rotation, and revolution, and there were more misconceptions in the drawn explanation than in the written explanation. Second, by analyzing the pre-service teachers' perceptions by combining written and drawn explanations, it is possible to detect scientific errors that the distance between the Earth and the Sun is closer when the axis of rotation is tilted in relation to the revolution and seasonal changes due to changes in the orbital radius of the Earth. In addition, there have been types of explanations such as seasonally changing meridian altitudes related to the rotation of the Earth but no change in the location of the Sun. Based on the results of the analysis, we discussed the lack of experience in constructing an explanatory system of specific phenomena using scientific knowledge, lack of observational experiences about natural phenomena, and lack of exposure to other explanatory systems that cause cognitive conflicts. We hope that it will be concrete and practical help to improve the understanding of pre-service teachers in the science domain of primary teacher training program.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.2 no.2
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• pp.161-172
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• 1969

Ten experimental tuna long line fishing operations were performed with the long lines A and B, in combination casting orders of BA and AB. The long line B differs from A in its additional main line length per basket and its greater depth of submersion (Table 1). The BA casting order results in an AB hauling order, so that the long line B is casted at an earlier time of a day and fishes for a longer period than A line (fig. 2). The number of fish caught was divided into subclasses in order to be subjected to $x^2-tests$ (Table 2). The first series of $x^2-tests$ were calculated using the hooking rates of two subclasses with other factors pooled (Table 3). The second series of $x^2-tests$ were calculated to obtain the interactions between two subclasses when other factors differed (Table 4). Attention was paid to the extremely small interactions as well as to the large interactions in order to find out whether a factor functions in the same way or in a contradictory way when the other factors involved differ. The test result is summarized in Table 5. The relationship between the hook casting time (relative to the sunrise time) and the hooking rates reveals the feeding behavior of particular species (fig. 3) A high hooking rate for yellowfin tuna shown in the period from one hour before sunrise to the moment of sunrise suggests that they feed actively in that period. Their poor hooking rate on earlier casted hooks suggests that they do not feed well under conditions of darkness and that they feed best while the hooks are sinking. Furthermore it is likely that yellowfin tuna maintain a shallow depth in the daytime, for the $x^2$ interaction between the line casting order BA and AB shows their persistant preferance of the long line A regardless of line casting order. Bigeye tuna show their feeding behavior under conditions of darkness, and show a preference for the sea's deeper layer. Alepisaurus borealis (Gill) show their feeding behavior under conditions of darkness more significantly than the bigeye tuna and their preferance for deep layers is also more significant. Marlins (mainly Makaria mazara) show a feeding behavior which is similar to the yellowfin tuna. The author emphasizes that certain variations of the hooking rates in relation to the line easting time were caused by an inadequate fishing depth as well as by the fish preference for a particular feeding time. When the part of the line casted in pre-dawn hours and hauled in the pre-sunset hours show a significantly lower hooking rate than other parts of the line, then it is concluded that tile hooks settled in a sea layer too deep for feeding.

• Journal of Distribution Science
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• v.12 no.8
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• pp.123-132
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• 2014

Purpose - Recently, Korean companies have been struggling to perform well in the larger smartphone market in China, which is regarded as a blue ocean area. First, it is very important to accurately understand the Chinese consumers, who have a different consumption culture and value system from the Korean culture and system. This would help to identify priorities for the Chinese market. Further, considering the smartphone industry, where technological change is rapid, Korean companies will need to take prompt measures about market trends in order to establish strong competitiveness. Consequently, this study focused on analyzing the relationship between the variables of consumption value, satisfaction, and loyalty in the Chinese smartphone market. The principal dimensions of consumption value, which smartphones have, was analyzed, and the influence on satisfaction was identified. Moreover, the relationship among the variables of satisfaction, attitudinal loyalty, and behavioral loyalty was empirically analyzed. Research design, data, and methodology - This study examined the relationships between various consumption values (functional value, emotional value, social value, epistemic value, and economic value), along with satisfaction and loyalty. The data were collected through a questionnaire survey that was circulated to 310 customers who were users of smartphones in Chingdao and Yeontae regions in China. The survey was conducted from June 23 to August 4, 2013. A total of 301 responses to the questionnaires were collected and used for the data analysis. Moreover, a path analysis based on Lisrel 8.54 was used for the hypothesis test. Results - The variables of functional value, emotional value, social value, and epistemic value were revealed to have positive effects on satisfaction related to smartphone usage. However, the variables of monetary cost and psychological cost were not found to have negative effects on satisfaction related to smartphone usage. Moreover, satisfaction positively influenced attitudinal loyalty related to smartphone usage, but did not have a significant influence on behavioral loyalty related to smartphone usage. Specifically, satisfaction is essential, but not a sufficient condition for building behavioral loyalty in relation to smartphone usage. In addition, attitudinal loyalty positively influenced behavioral loyalty in relation to smartphone usage. Conclusions - First, this study shows that functional value, emotional value, social value, and epistemic value in relation to smartphone usage are important for marketing in the Chinese smartphone market. Particularly, functional value and emotional value play pre-eminent roles as regards customer loyalty in the use of smartphones. Second, the results of this study reveal that the variables of monetary cost and psychological cost are not important to the Chinese consumers. Specifically, the smartphone price and cognitive effort are not perceived as value barriers. Third, satisfaction did not guarantee behavioral loyalty in relation to smartphone usage, and the strategic approach for improving the repurchase and referral action in relation to smartphones based on solid attitudinal loyalty would be desirable and should be the focus of the marketing activities of Korean smartphone companies.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.3
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• pp.1-11
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• 2010

In this study, we studied strategic directions of urban management through evaluation the value of the investment with the consideration of the development plan, the condition of the location, the potential of the site, green and disaster prevention infrastructure, focused on Gugal-dong(Gugal Station area) and the region of Bora, Jung-dong, in Yongin city. In terms of the methodology, we tried to decide using Analytic Network Process which can consider the relation between the evaluation items. In conclusion, for the development plan, the order of evaluation items is development purpose, key tenant, fund raising and marketing, and for the condition of the location, the order of evaluation items is land use, surrounding environment, and traffic environment, and for the development potential, the order is marketability, identity, and historic character, and for the green and disaster prevention infrastructure, the order is prevention of human, natural, social disaster. The significance of the conclusion of this study is that it can be utilized in pre-evaluation in planning the urban development.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4C
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• pp.193-200
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• 2010

This study suggests a method predicting at-rest coefficient of earth pressure ($K_0$) in order to evaluate the effect of stress history of granular soil. The method is based on the relation $K_D/K_0={\chi}(E_D/{\sigma}_m{^{\prime}})^{\delta}$, which is developed by combining two previously published relations such as $E_D/{\sigma}_m{^{\prime}}-{\psi}$ and $K_D/K_0-{\psi}$. As $K_D$ and $E_D$ are observed to be sensitive to the pre-stress, both indices are adopted for the estimation of $K_0$ value of granular soil. It is shown that the proposed $K_D/K_0-E_D/{\sigma}_m{^{\prime}}$ relation is insignificantly affected by the stress history. It is concluded from the comparative study that the proposed method, which uses only dilatometer test results to predict the $K_0$ of granular soil, provides more convenient and reliable prediction than other methods which use both CPT and DMT results.