• Journal of the Korean School Mathematics Society
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• v.13 no.2
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• pp.263-287
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• 2010

The purposes of the study were to investigate how children define a triangle, their reasoning types in identifying examples and non-examples of a triangle, and the relationship between their reasoning types and geometrical levels. Twenty-nine students consisted of 3th to 6th grades were involved in the study. Using the van Hiele levels of geometrical thought, children's reasoning types for identifying a figure as a triangle or non-triangle were categorized into visual reasoning, reasoning based on the figure's attributes and formal reasoning. The figure's attributes were further divided into critical and non-critical attributes. Most children identified a figure as a triangle or non-triangle based on critical attributes of the figure(e.g. closed figure, three, vertices, straight sides etc.) Some children identified a figure based on non-critical attributes of the figure(e.g. the length of the sides, the measurement of the angles, or the orientation of the figure). Particularly, some children who had lower levels of geometry identified a figure using visual reasoning, taking in the whole shape without considering that the shape is made up of separate components.

• Journal of the Korean association of regional geographers
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• v.12 no.6
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• pp.733-747
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• 2006

This paper aims to grasp the characteristics of the cognition and preference on the continents, their relationship, and then each nation's location and direction in case of Korean high school students. First, there exists difference of cognition by six continents as well as by gender and experience of foreign visit among the students. The students have somewhat different preference by each continent, which was affected by gender and experience of foreign visit as well. Second, the cognition of the students on each nation's location showed a positive relation with that on the continents, which was decided by adjacent distance with Korea. The empirical results showed that the higher the gaps of latitude over longitude are, the lower the cognition of the students on direction among nations are. Moreover there are significant gaps by gender and experience of foreign visit in orientation ability. As a result, the geography education may have to be develop the high school students' balanced cognition ability in relation to continents and nations.

• Wind and Structures
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• v.23 no.6
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• pp.615-639
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• 2016

Although the underlying mechanism of rain-wind induced vibrations (RWIVs) of stay cables has not been fully understood, some countermeasures have been successfully applied to mitigating this kind of vibration. Among these, installing dampers near the bridge deck was widely adopted, and several field observations have shown its effectiveness. In this study, the effectiveness of dampers to RWIVs of stay cables is numerically investigated comprehensively by means of finite difference method (FDM). Based on the free vibration analysis of a taut string, it is found that the 3-points triangle scheme, which can be easily implemented in FDM, can offer an excellent approximation of the concentrated damping coefficient (expressed as a Dirac delta function) at the location where the damper is installed. Then, free vibration analysis of a 3-D continuous stay cable attached with two dampers is carried out to study the relationship of modal damping ratio and damping coefficient of the dampers. The effects of orientation of the dampers and cable sag on the modal damping ratio are investigated in detail. Finally, the RWIV response of a 3-D continuous stay cable attached with two dampers is examined. The results indicate that 0.5% of damping ratio is sufficient to reduce the RWIV vibration of the Cable A20 on the No.2 Nanjing Bridge over Yangtze River.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.3
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• pp.189-204
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• 2015

This paper presents the results of reduced scale model tests on the effect of fault zone characteristics on the tunnel deformation behavior. A series of model tests were carried out on deep tunnels considering different fault zone orientations and offset distance. The tunnelling process was simulated in the model tests using compressed air technique. During the tests, the tunnel and ground deformation were mainly monitored while reducing the pressure inside the tunnel and the relationship between the pressure level and the tunnel deformation were established. The results indicate that for a given offset distance the tunnel behavior is influenced the most when the fault zone dips vertically while smallest influence occurs when the fault zone dips 45 degrees.

• Environmental Engineering Research
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• v.22 no.4
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• pp.407-416
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• 2017

$CO_2$ emission is increasingly focused by public. Beijing and Tianjin are conceived to be a new economic point of growth in China. However, both of them are suffering serious environmental stress. In order to seek for the effect of socioeconomic factors on the $CO_2$ emission of this region, a novel methodology -symbolic regression- is adopted to investigate the relationship between $CO_2$ emission and influential factors of Beijing and Tianjin. Based on this method, $CO_2$ emission models of Beijing and Tianjin are built respectively. The models results manifested that Beijing and Tianjin own different $CO_2$ emission indicators. The RMSE of models in Beijing and Tianjin are 255.39 and 603.99, respectively. Further analysis on indicators and forecast trend shows that $CO_2$ emission of Beijing expresses an inverted-U shaped curve, whilst Tianjin owns a monotonically increasing trend. From analytical results, it could be argued that the diversity rooted in different development orientation and the mixture of different natural and industrial environment. This research further expands the investigation on $CO_2$ emission of Beijing and Tianjin region, and can be used for reference in the study of carbon emissions in similar regions. Based on the investigation, several policy suggestions are presented.

• Journal of Korean Library and Information Science Society
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• v.30 no.2
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• pp.55-75
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• 1999

Although the importance of research methodoogy in library and information science(LIS) has been widely recognized, LIS has been also criticized that current research methodology in the field maintains only the positivistic orientation. Researchers on the other hand, assert that US should be studied as a human study, a subjective approach based on a phenomenological perspective, since US has very much to do. with the 'human factor,' with subjectivity in the form of librarian, patron, and administrator. In this paper, a review of the published qualitative research in the field which try to generate theories from the subjects in their own everyday life situation, attempts to shed light on the implication of a new terrain of everyday life research to US. Theory of everyday life is generated by the subjects who are involved in the social relationship, using their own language. It is a theory which shows the logic of the real world in which the everyday man recognize, act and communicate. This includes the perceptions, feelings, and meanings members experience as well as the 'small world' they create in process. Everyday life research performed using qualitative research methods which have strength to investigate this micro-structure applied to the field of library and information science, may bring enrichment to the library and information science research.

• Journal of Distribution Research
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• v.10 no.2
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• pp.1-26
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• 2005

The purpose of this study is to identify the consumer factors influencing the channel choice in the brokerage transaction. The 14 consumer factors were extracted from the two perspectives: first, the off-line channel is based on the relational benefits offered by the salespeople, second, the on-line stock exchange is a transaction mediated by the internet technology. The results shows that the channel choice is significantly influenced by the 8 out of 14 consumer factors hypothesized: interpersonal orientation, risk-taking tendency, amount of money invested, price consciousness, time length of internet usage, innovativeness, information privacy sensitivity, intrinsic desire for information. And the results of discriminant analysis shows that three consumer factors-risk-taking tendency, time length of internet usage, and information privacy sensitivity-are most valuable in discriminating off-line vs. on-line customers.

• Journal of Information Technology Services
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• v.17 no.2
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• pp.143-163
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• 2018

The business models has a great impact on the successful management of enterprises. Business environment has been shifting from industrial economy to knowledge-based economy. Enterprises go through numerous trials for successful management in the changing environment. Along with trial tests, research areas have been growing simultaneously. Although many researches have been conducted with regard to business models, it is very insufficient to systematically analyze the knowledge flow of research. Accordingly, successive researchers who want to study the business model may find it difficult to establish the orientation of future application research based on understanding the process of changing the knowledge structure that have accumulated so far. This study is intended to determine the current state of the business model research and to understand the process of knowledge structure changes in keywords that appear in 2,667 business model articles in the SCOPUS database. Identifying the knowledge structure has been completed through social network analysis, a methodology based on the 'relationship', and the changes in the knowledge structure were identified by classifying them into four different periods. The analysis showed that, first, the number of business model co-author increases over time with the need for academic diversity. Second, the 'innovation' keyword has the biggest center in the network, and over time, the lower-rank keyword which was in the former period has emerged as the top-rank keyword. Third, the cohesiveness group decreased from 12 before 2000 to 5 in 2015 and also the modularity decreased as well. Finally, examining characteristics of study area through a cognitive map showed that the relationships between domains increased gradually over time. The study has provided a systematic basis for understanding the current state of the business model research and the process of changing knowledge structure. In addition, considering that no research has ever systematically analyzed the knowledge structure accumulated by individual researches, it is considered as a significant study.

• The Journal of the Korea Contents Association
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• v.20 no.9
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• pp.365-379
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• 2020

The purpose of this study identifies the patterns of students' learning motivation profiles on entrepreneurial educational motivation among a sample of university students from one of the Korean national university(n=614). This study also examines the relationship between students' learning motivation profiles and entrepreneurial intention and types of entrepreneurship. In order to explore the types of leaning motivation profiles, a latent profile analysis was employed. Result from LPA revealed five distinct types of learning motivation profiles fit the data best, and these five profiles are compared with students' entrepreneurial intentions and types of entrepreneurship. Results showed that Profiles (profile 5 and 4-high goal orientation) are associated with the higher level of entrepreneurial intention. Regarding the type of entrepreneurship, the majority of all students are interested in individual and co-entrepreneurship with friend regardless of the patterns of profiles.

• The Korean Journal of Rehabilitation Nursing
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• v.11 no.2
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• pp.90-98
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• 2008

Purpose: The purpose of this study was to examine the cognitive function and degree of dementia patient by doing clock drawing test and to explore the relationship among other dementia screening test. Method: The study subjects were 94 dementia in patients department. The data was collected by face to face interview by clinical psychologist from January 2007 to February 2008. The tools were Clock Drawing Test, K-MMSE, K-3MS and CDR Scale. Results: 1) The average score of CDT was 5.13 (2.54), of K-MMSE was 20.53 (4.85), of K-3MS was 61.66 (16.46), and of CDR was 1.2 (.72), those scores showed dementia. 2) There was a statistically the significant difference in CDT (F=2.83, p=.043) and CDR (F=2.00, p=.008) by age. CDT has shown the differences by gender (t=-2.42, p=.018) and education (F=7.66, p=.000). 3) There were significant relationships between CDT and K-MMSE (r=-.294. p=.004), K-3MS (r=-.335, p=.001), and CDR (r=.286, p=.008). Conclusion: It is believed that using CDT which measures the visuospatial ability of dementia patients and K-MMSE which assesses an ability of language and orientation and K-3MS at the same time helps examining the beginning and the progressive degree of dementia more easily and objectively.