• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.258-292
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• 1996

In the last year great interest appears to YBCO thin films preparation on different substrate materials. Preparation of epitaxial film is a very difficult problem. There are many requirements to substrate materials that must be fullfilled. Main problems are lattice mismatch (misfit) and similarity of structure. From paper [1] or follows that difference in interatomic distances and angles of substrate and film is mire important problem than similarity of structure. In this work we present interatomic distances and angle relations between substrate materials belonging to ABCO4 group (where A-Sr or Ca, B-rare earth element, C-Al or Ga) of different orientations and YBCO thin films. There are many materials used as substrates for HTsC thin films. ABCO4 group of compounds is characterized by small dielectric constants (it is necessary for microwave applications of HTsC films), absence of twins and small misfit [2]. There most interesting compounds CaNdAlO4, SrLaAlO4 and SrLaGaO4 were investigated. All these compounds are of pseudo-perovskite structure with space group 14/mmm. This structure is very similar to structure of YBCO. SLG substrate has the lowest misfit (0.3%) and dielectric constant. For preparation of then films of substrates of this group of compound plane of <100> orientation are mainly used. Good quality films of <001> orientations are obtained [3]. In this case not only a-a misfit play role, but c-3b misfit is very important too. Sometimes, for preparation of thin films substrates of <001> and <110> orientations were manufactured [3]. Different misfits for different YBCO faces have been analyzed. It has been found that the mismatching factor for (100) face is very similar to that for (001) face so there is possibility of preparation of thin films on both orientations. SrLaAlO4(SLA) and SrLaGaO4(SLG) crystals of general formula ABCO4 have been grown by the Czochralski method. The quality of SLA and SLG crystals strongly depends on axial gradient of temperature and growth and rotation rates. High quality crystals were obtained at axial gradient of temperature near crystal-melt interface lower than 50℃/cm, growth rate 1-3 mm/h and the rotation rate changing from 10-20pm[4]. Strong anisotropy in morphology of SLA and SLG single crystals grown by the Czochralski method is clearly visible. On the basics of our considerations for ABCO4 type of the tetragonal crystals there can appear {001}, {101}, and {110} faces for ionic type model [5]. Morphology of these crystals depend on ionic-covalent character of bonding and crystal growth parameters. Point defects are observed in crystals and they are reflected in color changes (colorless, yellow, green). Point defects are detected in directions perpendicular to oxide planes and are connected with instability of oxygen position in lattice. To investigate facets formations crystals were doped with Cr3+, Er3+, Pr3+, Ba2+. Chromium greater size ion which is substituted for Al3+ clearly induces faceting. There appear easy {110} faces and SLA crystals crack even then the amount of Cr is below 0.3at.% SLG single crystals are not so sensitive to the content of chromium ions. It was also found that if {110} face appears at the beginning of growth process the crystal changes its color on the plane {110} but it happens only on the shoulder part. The projection of {110} face has a great amount of oxygen positions which can be easy defected. Pure and doped SLA and SLG crystals measured by EPR in the<110> direction show more intensive lines than in other directions which allows to suggest that the amount of oxygen defects on the {110} plane is higher. In order to find the origin of colors and their relation with the crystal stability, a set of SLA and SLG crystals were investigated using optical spectroscopy. The colored samples exhibit an absorption band stretching from the UV absorption edge of the crystal, from about 240 nm to about 550 m. In the case of colorless sample, the absorption spectrum consists of a relatively weak band in the UV region. The spectral position and intensities of absorption bands of SLA are typical for imperfection similar to color centers which may be created in most of oxide crystals by UV and X-radiation. It is pointed out that crystal growth process of polycomponent oxide crystals by Czochralski method depends on the preparation of melt and its stoichiometry, orientation of seed, gradient of temperature at crystal-melt interface, parameters of growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth. Growth parameters have an influence on the morphology of crystal-melt interface, type and concentration of defects.

• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1208-1221
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• 2020

The purpose of this study was to provide basic data for predicting the sports consumption market that Generation Z will lead by applying data mining based decision tree analysis to explore Generation Z sports consumption style. Therefore, the survey was conducted by selecting males and females aged 19 or older as a sample among Generation Z, and data of 429 people were used for the final analysis. For data processing, frequency analysis, exploratory factor analysis, retest and reliability analysis, and decision tree analysis were performed using the SPSS statistics (ver. 21.0) program. The main results of this study are as follows. First, if the rational efficiency index is high and the aesthetic consumption index is low, the probability of being classified as a group of female was 96.8%. On the other hand, if the rational efficiency and perception of price index were low, the probability of being classified as a male group was 100%. Second, if the brand orientation, perception of price, and rational efficiency index were high, the probability of being classified as a capital area group was 97.3%. Contrary to the results presented above, the probability of being classified as a other area group was 82.1% when the brand orientation, commemoration rites, and status symbol index were low. Third, the status symbol and trend oriented index were high, and if the functionality index was low, the probability of being classified into daily life and fashion groups was 77.6%. On the contrary, if the status symbol index is low, the retention of membership and enjoy consumption index is high, the probability of being classified into exercise and competition groups was 81.0%.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.14-27
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• 2015

This study aims to analyze the influence of bakery cafes servicescape on customer satisfaction and revisit intention, and to verify the mediating effect of customer satisfaction on the relationship between servicescape and revisit intention. This study targeted 10 bakery cafes located in Seoul, and after asking the persons concerned of the bakery cafes to check understanding, a survey with customers aged 20 or over was conducted over 10 days from March 15th to 24th 2015. A total of 250 self-administered questionnaires were distributed, and 244 questionnaires(97.6%) were used for study analysis after the exclusion of 6 incomplete and unreliable responses. To investigate the demographic characteristics of the respondents, a frequency analysis was carried out; for verification of the reliability and validity of the measuring tools, a reliability analysis and exploratory factor analysis were carried out; and for verification of the research hypotheses, simple and multiple regression analyses as well as a mediation analysis were carried out. All the data required for this study were analyzed using the SPSS 18.0 statistic program. The study findings showed that servicescape influenced customer satisfaction and revisit intention, and that Customer satisfaction had a mediating effect. Based on these findings, future marketing strategies and differentiated servicescape application methods for bakery cafes were suggested. Moreover, the limitations of the study and orientation for further research were discussed.

• Journal of Agricultural Extension & Community Development
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• v.21 no.2
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• pp.185-209
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• 2014

The aim of this study was to examine middle school students' career attitude maturity with five career elements(career decisiveness, goal orientation, confidence, preparation, and independence) related to relational(parent, teacher, friend) and school adjustment (school life, instruction, environment) variables. To accomplish this, 467 collected data was passed through correlation, and simple and multiple regression analysis using SPSS win 12. The main finding was that friend's support was highly correlated to and significantly affected career preparation and independence of the students. School life and instruction were also highly correlated to their career preparation. Parents' and teachers' support affected their career decisiveness. Their school life was an important factor to influence career decisiveness, preparation, and independence of the students. Generally, friends' support and school life of the students were the most important factors that affected the students' career preparation and independence. From the findings, this study suggests that middle schools need to provide more vocational education, diverse after-school activities, and teacher training to support middle school students' career attitude maturity.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.4
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• pp.15-26
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• 2008

The purpose of this study is to attempt to interpret golf courses as event-generating spaces with consideration given to the time factor. Through a golf game, a variety of events such as the tee shot, second shot, putt, and hole out are generated. These events have been connected to a series of events after hole out such as birdie, par, bogey and so on. The series of events do not always occur in the same way. They reveal unexpected changes over time. These unexpected changes cause changes in the spatial characteristics and offer unforgettable memories for golfers. Gilles Deleuze mentioned the spatial characteristics as striated space and smooth space. Striated space can be defined as sedentary space. It is distant vision-optical space that has dimensional, metric and centered characteristics, whereas smooth space is defined as nomadic, close vision-haptic space that has directional and acentered characteristics. This study focused on the analysis of spatial characteristics according to striated space and smooth space. Golf courses generally show the characteristics of striated space before beginning the game. As soon as the game begins, however, the golf courses are converted into an event-generating space. The characteristics of striated space are transformed into smooth space, a nomadic space that amplifies the dynamic, changeable, de-scaled and non-metric system. Through the whole game, this transformation is dramatically repeated. On the other hand, the golfer, the subject of the game, senses the phenomenological experience in the process of orientation, center, definition, and domestication.

• Korean Journal of Remote Sensing
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• v.34 no.2_1
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• pp.203-211
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• 2018

Dam discharge is carried out for the management of rivers and area around rivers due to rainy season or drought. Dam discharge should be based on an accurate understanding of the flow rate that can be accommodated in the river. Therefore, understanding the allowable storage capacity of river is an important factor in the management of the environment around the river. However, the methods using water level meters and images, which are currently used to determine the allowable flow rate of rivers, show limitations in terms of accuracy and efficiency. In order to solve these problems, this paper proposes a method to automatically calculate the allowable storage capacity of river based on the images taken by drone. In the first step, we create a 3D model of the river by using the drone images. This generation process consists of tiepoint extraction, image orientation, and image matching. In the second step, the allowable storage capacity is calculated by cross section analysis of the river using the generated river 3D model and the road and river layers in the target area. In this step, we determine the maximum water level of the river, extract the cross-sectional profile along the river, and use the 3D model to calculate the allowable storage capacity for the area. To prove our method, we used Bukhan river's data and as a result, the allowable storage volume was automatically extracted. It is expected that the proposed method will be useful for real - time management of rivers and surrounding areas and 3D models using drone.

• Journal of Science Education
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• v.44 no.1
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• pp.74-83
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• 2020

The purpose of this study is to investigate motivation to learn physics in order to understand engineering college students' physics learning. Therefore, in this study, 374 engineering students at the university located in Seoul were studied using the Physics Motivation Questionnaire (PMQ), which was a Science Motivation Questionnaire II modified into the context of learning physics. The PMQ is composed of five factors: intrinsic motivation, career motivation, self-determination, self-efficacy, and grade motivation. It involves 25 Likert scale items. Through exploratory factor analysis, PMQ confirms that the five factors are structurally valid in measuring the motivation of engineering students to learn physics. In addition, item fit (MNSQ) was also confirmed using a Rasch model analysis. The results show that grade motivation has the highest mean with 4.2, followed by job motivation mean with 3.76. The mean of intrinsic motivation was 3.42, the self-efficacy was 3.38, and self-determination was 3.32. The results of this study confirm that the physics learning motivation of engineering college students is characterized showing high external motivation related to job and grade. Therefore, we should try to develop the teaching strategy to increase intrinsic motivation by developing mastery goal orientation of physics learning for engineering students.

• Journal of Korea Port Economic Association
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• v.26 no.3
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• pp.259-278
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• 2010

This study analyzes the achievement of the shipping policies and the priority for the promotion of such policies, in order to consider the features of the shipping industries in Korea and other advanced shipping countries and manage the rapidly changing shipping environment actively. Based on such analysis, this study also discusses the promotional strategy to strengthen the international competitiveness of the shipping industry. Regarding the promotion of the related policies, it is necessary to establish a base for growth, strengthen a capacity of leading the market, and create an opportunity in the market. By considering such three factors, it has become known that the establishment of the market order is important for the establishment of a base for growth. It is important to consider the advancement of the shipping tax system. Also, the information-orientation and the knowledge-industrialization of the shipping industry need to be considered. In order to strengthen a capacity of leading the market, the stable security of the labor force in the shipping industry is the most important factor. Also, it is important to consider the development and the upbringing of the global mega career and the shipping business. Regarding the creation of an opportunity in the market, it is important to expand the range of the shipping exchange between South Korea and North Korea, which will influence the administrative and the operative results related with the promotion of the related policies.

• Journal of The Korean Association For Science Education
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• v.37 no.3
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• pp.395-405
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• 2017

This study aims to investigate the effects of socioscientific issues (SSI) instruction on promoting college students' character and values as citizens, and to compare the effects based on the psychological factor - idiocentrism and allocentrism. Thirty-one college students who enrolled in the SSI course participated in this study. The SSI course provided the students with opportunities to explore various aspects of five topics, to express and share their own opinions, and to identify reasonable alternatives. The students with distinct tendencies were classified into two groups (i.e. idiocentric and allocentric groups) based on the personal value orientation scores before the instruction, and they responded to the questionnaire to examine their character and values as citizens before and after the instruction. The results showed that the students' social and moral compassion and socioscientific accountability improved significantly after the SSI course. The overall effects of the SSI program on students' character and values were not significantly different between two groups. However, the post-mean score of the allocentric group in socioscientific accountability was higher than the one of the idiocentric group. This study shows that SSI instruction could positively affect character development regardless of psychological tendencies, and could be implemented in the science classroom as a good instructional approach to integrating science education and character education.

• Journal of the Korea Convergence Society
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• v.10 no.12
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• pp.81-91
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• 2019

This study empirically examines the relationship between the characteristics of a company and its performance through open innovation. It was intended to accept open innovation as a strategic means to overcome various situations in which companies faced and to understand it as a process of generating corporate performance. In various situations, companies must overcome environmental and internal factors. As an environmental factor, the dynamics of the market and the dynamics of technology allow for the adoption of open innovation, which in turn becomes a strategic tool for generating results. In addition, the internal environment of the company should strengthen the organization's capacity considering the characteristics of the company. In order to reinforce entrepreneurial orientation, openness of organizational culture, delegation and R & D capabilities, which are internal characteristics of the company, open innovation has a positive effect on the performance of the company. In overcoming the environment given to the company, open innovation was found to be an important medium for generating various results for the company. For this study, we conducted a structured questionnaire survey on 176 Korean companies. This study suggests that open innovation is strategically accepted and understood as a management strategic philosophy in order to overcome the environment in which a company is faced and generate results.