• School Mathematics
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• v.14 no.1
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• pp.135-150
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• 2012

This paper analyzes the activities for (fraction) ${\times}$(fraction) in Korean elementary textbooks focusing on the connection between visual models and the algorithm. New Korean textbook attempts a new approach to use length model (as well as rectangular area model) for developing the standard algorithm for the multiplication of fractions, $\frac{a}{b}{\times}\frac{d}{c}=\frac{a{\times}d}{b{\times}c}$. However, activities with visual models in the textbook are not well connected to the algorithm. To bridge the gap between activities with models and the algorithm, distributive strategy should be emphasized. A wealth of experience of solving problems of fraction multiplication using the distributive strategy with visual models can serve as a strong basis for developing the algorithm for the multiplication of fractions.

• Publications of The Korean Astronomical Society
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• v.27 no.4
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• pp.281-284
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• 2012

We utilize AKARI's slitless spectroscopic capability to detect the $3.3{\mu}m$ polycyclic aromatic hydrocarbons (PAHs) emission and measure star formation (SF) activity for various AKARI programs. First, we obtain $2{\sim}5{\mu}m$ spectra of 20 flux-limited galaxies with mixed SED classes in order to calibrate the $3.3{\mu}m$ PAH luminosity ($L_{PAH3.3}$) as a star formation rate (SFR) indicator. We find that $L_{PAH3.3}$ correlates with $L_{IR}$ as well as with the $6.2{\mu}m$ PAH luminosity ($L_{PAH6.2}$). The correlations does not depend on SED classes. We find that ULIRGs deviate from the correlation between PAH luminosities and $L_{IR}$, while they do not for the correlation between PAH luminosities. We suggest possible effects to cause this deviation. On the other hand, how AGN activity is linked to SB activity is one of the most intriguing questions. While it is suggested that AGN luminosity of quasars correlates with starburst (SB) luminosity, it is still unclear how AGN activity is connected to SF activity based on host galaxy properties. We are measuring SFRs for the LQSONG sample consisting of reverberation mapped AGNs and PG-QSOs. This is an extension of the ASCSG program by which we investigated the connection between SB and AGN activities for Seyferts type 1s at z ~ 0.36. While we found no strong correlation between $L_{PAH3.3}$ and AGN luminosity for these Seyferts 1s, $L_{PAH3.3}$ measured from the central part of galaxies correlates with AGN luminosity, implying that SB and AGN activities are directly connected in the nuclear region.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.6
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• pp.699-705
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• 2011

High-maneuver missile is a projectile which demands a strong momentum at short time. To produce a necessary thrust for the flight, the gas of high temperature and pressure is generated through explosive combustion of solid propellant, and a great thrust can be obtained by expanding this high temperature and pressure gas. Although the operating time of a rocket motor is less than a few seconds, a failure of part or ablation near the throat of nozzle may take place during the expansion of high temperature and pressure gas for great thrust. In other words, for the precise control of a missile an exact stress analysis considering both, the thermal stress caused by the heat transfer between combustion gas and wall, and the mechanical stress caused by the pressure change in the flow, should be considered first. In this connection, this study investigated the safety, as a point of view of stress and melting point of the material, of the pre-designed thrust generating structure which is subjected to high temperature and pressure as a function of motor operating time.

• Journal of the Earthquake Engineering Society of Korea
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• v.18 no.1
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• pp.37-43
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• 2014

In current seismic design code, steel moment frames are classified into ordinary, intermediate, and special moment frames. In the case of special moment frames which have large R-factor, economic design is possible by reducing the design lateral force. However, there is difficulty for practical application due to constraints such as strong column-weak beam requirement. This study evaluated if steel intermediate moment frame could maintain enough seismic capacity when the R-factor is increased from 4.5 to 6. As for the analytical models, steel moment frames of 3 and 5 stories were categorized into four performance groups according to seismic design category. Seismic performances of the frames were evaluated through the procedure based on FEMA P695. FEMA P695 utilizes nonlinear static analysis(pushover analysis) and nonlinear dynamic analysis(incremental dynamic analysis, IDA). In order to reflect the characteristics of Korean steel moment frames on the analytical model, the beam-column connection was modeled as weak panel zone where the collapse of panel zone was indirectly considered by checking its ultimate rotational angle after an analysis is done. The analysis result showed that the performance criteria required by FEMA P695 was satisfied when R-factor increased in all the soil conditions except $S_E$.

• Korean Journal of Remote Sensing
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• v.32 no.4
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• pp.353-364
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• 2016

Yangon city is experienced a rapid urban expansion over the last two decades due to accelerate with the socioeconomic development. This research work studied an investigation into the application of the integration of the Remote Sensing (RS) and Geographic Information System (GIS) for observing Land Use and Land Cover (LULC) patterns and evaluate its impact on Land Surface Temperature (LST) of the downtown, suburban 1 and suburban 2 of Yangon city. The main purpose of this paper was to examine and analyze the variation of the spatial distribution property of the LULC of urban spatial information related with the LST and Normalized Difference Vegetation Index (NDVI) using RS and GIS. This paper was observed on image processing of LULC classification, LST and NDVI were extracted from Landsat 8 Operational Land Imager (OLI) image data. Then, LULC pattern was linked with the variation of LST data of the Yangon area for the further connection of the correlation between surface temperature and urban structure. As a result, NDVI values were used to examine the relation between thermal behavior and condition of land cover categories. The spatial distribution of LST has been found mixed pattern and higher LST was located with the scatter pattern, which was related to certain LULC types within downtown, suburban 1 and 2. The result of this paper, LST and NDVI analysis exhibited a strong negative correlation without water bodies for all three portions of Yangon area. The strongest coefficient correlation was found downtown area (-0.8707) and followed suburban 1 (-0.7526) and suburban 2(-0.6923).

• Journal of Korea Port Economic Association
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• v.31 no.4
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• pp.227-240
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• 2015

Asia's cruise industry is growing rapidly with the number of tourists increasing every year. This growth has encouraged intense competition among leading port cities in Asia to retain cruise tourists and cruise lines. The purpose of this study is to analyze the development of the cruise industry around Busan as a hybrid port city and propose new strategies for improving Busan's competitiveness. To achieve these goals, factor analysis and Importance-performance analysis (IPA) are used. The analyses results suggest that the development possibility of Busan as a cruise center is dependent on the improvement of certain factors, including the variety of inland tour options, unique experience, direct service infrastructure, tourist attractions, wide accessibility to other modes, and strong connection to attraction. In addition, the city needs to meet other requirements, including developing various tours, tourist products, and fly & cruise packages and hosting international festivals that can represent Busan and cater to potential cruise customers. Moreover, the city desperately needs to expand its commercial and cultural space by redeveloping its cruise terminals.

• International Commerce and Information Review
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• v.12 no.2
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• pp.59-83
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• 2010

The purposes of the study is to evaluate the discrepancy between user's expectation and satisfaction degree in the service of uTradeHub. In this regard, this study infers general solutions in order to induce the intersection area using IPA technique. Then this paper will present directions to improve the service of uTradeHub. In terms of methodology, this article disclosed that IPA model approach is greatly useful to evaluate user's attribute. First, variables like the link of different works(f1), trust of system(f4), information connection(f7) are located on the first quadrant. This means that importance and satisfaction are all high variables for user. So, this is very important variables that need continuous administration in order to maintain present state. Second, variables such as the speed of information acquisition(f2), improvement of use(f3), stability of system(f5) are located on the second quadrant. This means that user's importance is high but user's satisfaction is low. Therefore, this area needs an active improvement strategy and quick maintenance for e-Trade application. Third, variables like the appropriateness of information usage fees(f8), easy subscription(f9), customer support service(f10) are located on the third quadrant. Because these variables are all low for user's importance and satisfaction, we have to arrange strong and radical remedy for e-Trade service. Finally, variables like information offer(f6) are located on the fourth quadrant. This means that user's satisfaction is high but user's importance is low. The research result suggests that e-Trade service development would be re-organised as much as user feels the importance of process innovation.

• International Commerce and Information Review
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• v.13 no.3
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• pp.55-74
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• 2011

Web Service applications based on the social relation such as Social Network Service(SNS), Social Medias are making strong blast. Social Computing which is widely spreading to worldwide is affecting to our life including policies, economies, societies and culture. Based on Web 2.0, various services like as Social Collaboration, Social Publishing, Social Feedback are supplied, more evolved social computing services, Social Connection, Augmented Reality, will be served for the next days from now. These network based services, Social Network Service or Social Media frequently used terms, are not defined exactly and their characteristics are not gotten to the bottom yet. Theoretical and systematic studies on these themes are not made also. Applications to business area, especially the receptivity to social computing in international trade is barely made to these days. This study focuses on the concepts, characteristics and sorts of social computing and purposes to consider its possibilities of application of social computing to international trade. Considering the advantage of Social network service, it can be used in international trade, a kind of B2B transaction, while existing social network is mainly applied to B2e transaction.

• Journal of the Korea Convergence Society
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• v.11 no.6
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• pp.153-161
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• 2020

The present study aimed to investigate the relationships among consumers' personality trait, brand tribalism, and brand commitment through brand trust and perceived switching cost. Data were collected from a convenience sample of three-hundred and ninety-four undergraduate students at a large Korean university. The participants consisted of 54.1% female (N = 213) and 45.9% male (N = 181). The results indicated that extraversion, conscientiousness, and emotional stability traits are directly related to brand tribalism. Also, brand commitment was directly associated with brand tribalism, brand trust, and perceived switching cost. In particular, our results showed the relationship between brand tribalism and brand commitment was mediated by brand trust, but not perceived switching cost. Therefore, our findings suggest that strong emotional connection of brand tribes may increase perceived switching costs and, consequently, affect brand commitment.

• Korean Institute of Interior Design Journal
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• no.17
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• pp.65-72
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• 1998

This study intends to analyze the various spatial structures and characteristics of the museum based on the two of the Renzo Piano's recent projects Menil Collection '||'&'||' Museum and Beyeler Foundation Museum Which defined the direction of the "Third Generation" in museum architecture with reference to the quality of spatial experience and design applications. Comparison and analysis were done on the basic spatial organization floor layout accessibility exhibition area lighting plan and circulation between the two museum. Through the itemized common characteristics of the museum the architect's proposal on meaning and direction of the new museum architecture can be viewed. The contemporary museums distinguish themselves quite clearly from their predecessors and this applies both to their own form and to their spatial organization. As the public demands and requests toward the museum building facility expand everyday the architect must respond by providing multiple types of space where people can experience different atmosphere in each area. One concept he used to create multi experienced area was manipulation of the natural light using by the state-of-the-art techniques of the light filtering system and multi-layering roof system to protect the valuable collections against the direct sunlight. But mainly it was to prove his strong belief in "architecture of light" by creating space with minimized meaning by purposely distinguished area in order to provide maximum support to the physical value of the collection " The connection with nature" is another concept which Piano used to provide the public a tranquil experience through out the architecture which engages in a lively dialogue with art. In spatial organization Piano concerned on functionality which not only concentrated on the visitor's point of view but also on the museum staff's comfort. Unlkie the traditional museum he alternates various size of exhibition areas for spatial hierarchy. Specially the spatial flexibility that the temporary exhibition areas are able to be expanded to the permanent exhibition areas by adjoining t재 spaces differentiate Piano's new museum from the rest. museum from the rest.