• Journal of ILASS-Korea
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• v.26 no.3
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• pp.127-134
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• 2021

Fire sprinkler initial spray was analyzed by Large eddy simulation (LES) and Volume of Fluid (VoF) integrated method. The IsoAdvector geometric VoF was used to identify the liquid-gas interface clearly even with the large Courant-Friedrichs-Lewy number. To reduce the computational costs, sector meshes and Adaptive Mesh Refinement up to level 3 were used. Base mesh size was 1 mm, which is roughly equivalent to the initial sprinkler droplet. Top surface radius of boss and deflector size were modified to investigate the effects of sprinkler head design on primary breakup process. When top surface radius of boss was increased, vertical liquid sheet was formed. This phenomenon reduced the sheet breakup radius, sheet thickness and velocity. Due to reduced liquid sheet thickness, a large amount of ligaments was created from the liquid sheet. As a result, there was a dramatic decrease in volume per surface area, indicating an increase in breakup process. Spray pattern viewed in radial direction also changed when top surface radius of boss increased. When top surface radius of boss was increased, a T-shaped pattern was observed while a V-shaped pattern was observed in all other cases. When the deflector size increases, the spray pattern remains V-shaped, even if the top surface radius of boss increased. Further studies on promoting atomization of the water supplied to the lower part of the sprinkler head in the T-shape pattern should be conducted.

• The Mathematical Education
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• v.58 no.2
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• pp.187-223
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• 2019

This study aims to investigate the aspects of revision in the external and internal structure of curriculum and documentation in Korea and Japan and to propose the direction and task to enhance the current framework of the national curriculum. Japan has been selected for comparison in that it explicitly prepared social changes such as the dramatic evolution of artificial intelligence and population aging in its new curriculum. Therefore, various aspects of revision were analyzed the 2009 & 2015 revised mathematics curriculum of Korea and the 2008 & 2017 mathematics curriculum of Japan respectively in the elementary, middle, and high school grade bands. Then, the differences between the two countries were identified through comparison. First, the structure of the mathematics curriculum in Japan was connected with the general guidelines more tightly than Korea, and the external structure of the mathematics curriculum stayed consistently after the revision. Second, contrary to Korea, which pursued the appropriateness and reduction of mathematical content, Japanese mathematics curriculum has been pursuing detailed contents both quantitatively and qualitatively. Lastly, Japan emphasized statistical problem-solving ability. Based on this, we suggested considering of consistency in the structure curriculum documentation, detailing contents of the curriculum, and strengthening of statistical education.

• The Journal of the Korea Contents Association
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• v.21 no.8
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• pp.442-454
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• 2021

Many domestic and international airlines that experienced dramatic recession due to COVID-19 pandemic are carefully being ready to normalise operations as a number of governments has begun to vaccinate for COVID-19. So with the same market share from domestic to short distant international services, the competition between Full Service Carriers (FSC) and low cost carriers (LCC) is anticipated to be more intensive. To explore the concepts such as the perception, value, attitude and faith of the object, this study implements Q methodology proposed to complement the limitations of quantitative and qualitative research methodology. As a result, the consumers of airlines' brand are divided into three types - the type of utility seeking, value-oriented and task-related. Using Q samples which consist of 25 statements, this study specifically approached the traits of each type by observing the subjectivity with the comparative P sample group that is made up for 20 participants. By discovering the type of FSC and LCC's brand asset and comparing the recognition of consumers, not only does this study evoke the need for a strategic direction of the effective management of Airlines' Brand asset but also have a signification in the way that especially provide hypotheses for follow up studies.

• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.253-258
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• 2023

In comics, panels serve a variety of dramatic purposes, including controlling the flow of the story through the size, placement, and order of panels; directing the eye to where characters or specific actions take place; expressing the passage or sequence of time; and using backgrounds, lighting, and color to emphasize emotion and convey mood. When applied to VR animation, these comic panels can give users a more immersive experience of the cartoon world in the VR space. In the VR animation "Mescaformhill: Missing Five," produced in 2022, the comic panels directing is very important to guide the viewer's attention, and in the VR space, the camera angle can be freely changed to realize various visual effects, and the physical interaction brings the comic panels directing to life. This can open up new ways of storytelling in VR animation and contribute to its successful expansion into new mediums.

• Journal of Technology Innovation
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• v.31 no.3
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• pp.1-37
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• 2023

The Korean innovation ecosystem has evolved from a catch up stage to a creative leader stage where government's role in creating a private sector driven, healthy and dynamic ecosystem is important. Korea's innovation ecosystem shows a stagnation of innovation performance and a lack of linkage activities within the national innovation ecosystem and in global cooperation, despite the dramatic advancement and expansion of the ecosystem. A next-generation innovation ecosystem model is required to create a future-oriented innovation ecosystem. The next generation innovation ecosystem was prepared on the basis of the framework, which has 6 elements among which inter-firm network is the the micro-foundation of the ecosystem. On the basis of the framework, assuming that the next generation innovation ecosystem is the evolved existing ecosystem, responsive the discontinuous change in market and technology, which is private sector driven healthy and dynamic ecosystem, the next generation innovation ecosystem model was created. The concrete details on the direction of the policy entities responsible for building the ecosystem was presented, and the contribution of this study was discussed.

• Korean Journal of Construction Engineering and Management
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• v.19 no.2
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• pp.107-116
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• 2018

Since 2010, Korea's overseas construction orders have seen dramatic fluctuations. I propose causes and remedies for the industry as a whole. Orders have recorded an annual average of $63.8 billion dollars from 2011 to 2014, reaching its highest at $71.6 billion dollars(2010) which marked the peak of Korea's overseas construction. However, due to a decline in international oil prices, starting in the last half of 2014, Korea's overseas construction orders have followed suit recording $46.1 billion dollar in 2014, $28.2 billion dollars in 2016, and $29.0 billion dollars in 2017. Facing uncertainty in Korea's overseas construction market, caused by continued slow growth of the global economy, Korean EPC contractors are at a critical point in regards to their award-winning capabilities. Together with declining oil prices, the challenges have never been bigger. To mitigate the challenges, I would suggest policy direction as a way to grow and develop the overseas construction industry. Proper counterplans are needed to foster Korea's overseas construction industry. Forecasting total order amount for overseas construction projects is essencial. Analyzing contract award & tender structure and its changing trends in both overseas and world construction markets should also be included. Korea has great potential and global competitiveness. These measures will serve to enhance Korea's overall export strategy in uncertain overseas markets and global economy.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.1
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• pp.9-18
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• 2016

The slender structures such as high rise building or marine riser are highly susceptible to dynamic force exerted by fluid-structure interactions among which vortex-induced vibration(VIV) is the main cause of dynamic unstability of the structural system. If VIV occurs in natural frequency regime of the structure, fatigue failure likely happens by so-called lock-in phenomenon. This study presents the numerical analysis of dynamic behavior of both structure and fluid in the lock-in regimes and investigates the subjacent phenomena to hold the resonance frequency in spite of the change of flow condition. Unsteady and laminar flow was considered for a two-dimensional circular cylinder which was assumed to move freely in 1 degree of freedom in the direction orthogonal to the uniform inflow. Fluid-structure interaction was implemented by solving both unsteady flow and dynamic motion of the structure sequentially in each time step where the fluid domain was remeshed considering the movement of the body. The results show reasonable agreements with previous studies and reveal characteristic features of the lock-in phenomena. Not only the lift force but also drag force are drastically increasing during the lock-in regime, the vertical displacement of the cylinder reaches up to 20% of the diameter of the cylinder. The correlation analysis between lift and vertical displacement clearly show the dramatic change of the phase difference from in-phase to out-of-phase when the cylinder experiences lock-in. From the results, it can be postulated that the change of phase difference and flow condition is responsible for the resonating behavior of the structure during lock-in.

• Journal of Internet Computing and Services
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• v.20 no.3
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• pp.119-128
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• 2019

This study aims to analyze the research trends on Smart City and to present implications to policy maker, industry professional, and researcher. Cities around globe have undergone the rapid progress in urbanization and the consequent dramatic increase in urban dwellings over the past few decades, and faced many urban problems in such areas as transportation, environment and housing. Cities around the globe are in a hurry to introduce Smart City to pursue a common goal of solving these urban problems and improving the quality of their lives. However, various conceptual approaches to smart city are causing uncertainty in setting policy goals and establishing direction for implementation. The study collected 11,527 papers titled "Smart City(cities)" from the Scopus DB and Springer DB, and then analyze research status, topic, trends based on abstracts and publication date(year) information using the LDA based Topic Modeling approaches. Research topics are classified into three categories(Services, Technologies, and User Perspective) and eight regarding topics. Out of eight topics, citizen-driven innovation is the most frequently referred. Additional topic network analysis reveals that data and privacy/security are the most prevailing topics affecting others. This study is expected to helps understand the trends of Smart City researches and predict the future researches.

• Journal of Technology Innovation
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• v.27 no.1
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• pp.1-43
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• 2019

The significance of SMEs (small and medium-sized enterprises) is gradually highlighted as we have entered the age of "New Normal." The South Korean government support these enterprises to boost economic growth and create more jobs. It also releases numerous policies such as national R&D projects and expanding tax incentive services particularly aiming at promoting dramatic investment in R&D and technological innovation. There is a sharp contrast regarding the efficiency of direct or indirect supports for encouraging R&D investment launched by SMEs depending on researchers. However, there has been little attempt to explore the optimal combination of two policy tools. Amid promoting affiliated governmental departments in charge of SMEs policies and constantly growing R&D investment, it is an appropriate time to discuss the medium and long-term direction for the optimal policy mix of direct and indirect supports. In this study, the author obtained 32 relevant studies published earlier in the domestic journals, explored literatures more systematically, and further conducted a meta-analysis. It is dedicated to summarizing relevant controversies and organizes them empirically beyond merely verifying whether policy support stimulates private R&D investment by SMEs. The meta-analysis showed that it would be effective to support as tax for large enterprises, while subsidiary support for SMEs. However, indirect support needs to be progressively increased as direct support primarily accounts for the entire R&D support for South Korean SMEs.

• Journal of the Korea Convergence Society
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• v.12 no.6
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• pp.17-25
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• 2021

Population aging is an inevitable problem in our society nowadays, and the current aging trend in Asia is prominent and the number of elderly people is huge, among which the World Health Organization predicts that by 2050, 35% of China's population will be over 60 years old, making it the most serious aging country in the world. According to actual reports and surveys, there is a clear digital divide between a large proportion of the elderly and ICT technology, which has had a negative impact on the quality of life and mentality of the elderly living in cities due to the rapid development of technology and the dramatic changes that have occurred in urban life in recent years. The author chose Chinese urban elderly as the main research topic, the research method through the collation of existing literature and information combined with the actual data research, narrative collation of the current situation of ICT use among the Chinese urban elderly and the causes of the difficulties, summarize the ability of the Chinese urban elderly as the representative of the elderly users to master and learn ICT. The study concluded that the needs of the elderly for ICT are multi-layered and there is a gradation in the ability of the elderly users to master various ICT services, so that the elderly can better use and enjoy ICT services and provide teaching and services in a hierarchical and targeted manner can be the next research direction.