• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.2
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• pp.291-298
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• 2022

Recently developed drones are inexpensive and very convenient to operate. As a result, the production and utilization of spatial information using drones are increasing. However, most drones acquire images with a low-cost global navigation satellite system (GNSS) and an inertial measurement unit (IMU). Accordingly, the accuracy of the initial location and rotation angle elements of the image is low. In addition, because these drones are small and light, they can be greatly affected by wind, making it difficult to maintain a certain overlap, which degrades the positioning accuracy. Therefore, in this study, images are taken at different times in order to analyze the positioning accuracy according to changes in certain exterior orientation parameters. To do this, image processing was performed with Pix4D Mapper and the accuracy of the results was analyzed. In order to analyze the variation of the accuracy according to the exterior orientation parameters in detail, the exterior orientation parameters of the first processing result were used as meta-data for the second processing. Subsequently, the amount of change in the exterior orientation parameters was analyzed by in a strip-by-strip manner. As a result, it was proved that the changes of the Omega and Phi values among the rotation elements were related to a decrease in the height accuracy, while changes in Kappa were linked to the horizontal accuracy.

• The Journal of Engineering Geology
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• v.32 no.1
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• pp.173-191
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• 2022

In this study, the shear wave velocity of the ground was measured using Flat TDR, and the precision analysis of the measured value and the verification of field applicability were performed. The shear wave velocity measurement value was derived in the field using the piezo-stack combined in the Flat TDR. analyzed. As a result of the experiment, the average value of the change in shear wave speed at the time of grout material injection was 10.15 m/s at the beginning of age, and the average value of the change in shear wave speed after the 7th to 14th days was 65.99 m/s, showing a tendency to increase with age. Also, it was found that dry density and shear wave speed increased as the water content increased on the dry side, and that the dry density and shear wave rate decreased as the water content increased on the wet side as the water content increased. The shear modulus value derived from the field test was confirmed to be a minimum of 17.36 MPa and a maximum of 28.13 MPa, confirming a measurement value similar to the reference value. Through this, it can be seen that the measured value of the shear modulus using Flat TDR is reliable data, and it can be determined that the compaction management of the site can be effectively managed in the future.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.2
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• pp.265-278
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• 2022

The global energy paradigm is rapidly changing by centering on carbon neutrality, and wind energy is positioning itself as a leader in renewable energy-based power sources. The success of onshore and offshore wind energy projects focuses on securing the economic feasibility of the project, which depends on securing high-quality wind resources and optimal arrangement of wind turbines. In the process of constructing the wind farm, the optimal arrangement method of wind turbines considering the main wind direction is important, and this is related to minimizing the wake effect caused by the fluid passing through the structure located on the windward side. The accuracy of the predictability of the wake effect is determined by the wake model and modeling technique that can properly simulate it. Therefore, in this paper, using WindSim, a commercial CFD model, the wake diffusion pattern is analyzed through the sensitivity study of each wake model of the proposed onshore wind farm located in the mountainous complex terrain in South Korea, and it is intended to be used as basic research data for wind energy projects in complex terrain in the future.

• Journal of Intelligence and Information Systems
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• v.28 no.1
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• pp.1-28
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• 2022

In recent years, many Internet giants have begun providing their own content services, which attract online users by offering personalized services based on artificial intelligence technologies. This study investigates the role of two firms' content services within the firms' online service network. We examine the role of Naver Webtoon, which can be characterized as a professional-generated content, within Naver's service portfolio, and that of Google YouTube, which can be characterized as a user-generated content, within Google's service portfolio. Using survey data on viewers' use of the two services, we analyze a valued directed service network, where a node denotes an online service and a relationship between two nodes denotes a sequential use of two services. We found that both Webtoon and YouTube show higher out-degree centrality than in-degree centrality, which implies these content services are more likely to be starting services rather than arriving services within the firms' interactive network. The gap between the out-degree and in-degree centrality of YouTube is much smaller than that of Webtoon. The high centrality of YouTube, a user-generated content service, within the Google service network shows that YouTube's initial role of providing specific-content videos (e.g., entertainment) has expanded into a general search service for users.

• Journal of Technology Innovation
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• v.30 no.1
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• pp.1-20
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• 2022

Digital transformation refers to the economic and social effects of digitisation and digitalisation. Although digital transformation acts as a useful tool for economic/social development and enhancing the convenience of life, it can have negative effects (misuse of personal information, ethical problems, deepening social gaps, etc.). The government is actively establishing policies to promote digital transformation to secure competitiveness and technological hegemony, however, understanding of digital transformation-related risk issues and implementing policies to prevent them are relatively slow. Thus, this study systematically identifies risk issues of the future society that can be caused by digital transformation based on quantitative analysis of media articles big data through the Embedded Topic Modeling method. Specifically, first, detailed issues of negative effects of digital transformation in major countries were identified. Then detailed issues of negative effects of artificial intelligence in major countries and Korea were identified. Further, by synthesizing the results, future direction of the government's digital transformation policies for responding the negative effects was proposed. The policy implications are as follows. First, since the negative effects of digital transformation does not only affect technological fields but also affect the overall society, such as national security, social issues, and fairness issues. Therefore, the government should not only promote the positive functions of digital transformation, but also prepare policies to counter the negative functions of digital transformation. Second, the detailed issues of future social risks of digital transformation appear differently depending on contexts, so the government should establish a policy to respond to the negative effects of digital transformation in consideration of the national and social context. Third, the government should set a major direction for responding negative effects of digital transformation to minimize confusion among stakeholders, and prepare effective policy measures.

• Laboratory Medicine Online
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• v.1 no.2
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• pp.110-114
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• 2011

There have been a few reports of hemophagocytic lymphohistiocytosis (HLH) with chromosomal abnormalities. Clonal chromosomal abnormalities in HLH patients are usually found in association with hematologic malignancies and rarely with epstein-barr virus (EBV) infection. Here, we report a fatal case of HLH with clonal karyotype abnormalities. A 75-yr-old man was admitted with persistent anorexia and high fever. Laboratory data revealed pancytopenia, hypofibrinogenemia, hyperferritinemia, prolonged prothrombin time and activated partial thromboplastin time, and marked elevated level of serum transaminases. In real time-PCR using whole blood, EBV DNA was not detected but cytomegalovirus (CMV) DNA was detected. The bone marrow aspiration smear showed hyperplasia of mature histiocytes with prominent hemophagocytosis. In chromosomal analysis of bone marrow aspirates, complex chromosomal abnormalities were found. In spite of steroid pulse therapy and antibiotic treatment, he died of disseminated intravascular coagulopathy.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.9
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• pp.509-518
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• 2017

The purpose of this study is to investigate the experience of recognition struggle, which is a positive interaction with Korean society, through the life history research of the researcher ' The study was conducted as a narrative - life history analysis method. Life history data were collected through in-depth interviews. As a result of the study, the lifetime of the life history research subject, as a result of the constant challenge, considered Korea as the opportunity land and voluntarily migrated to Korea. He can analyze Korea as a fierce life to gain recognition by utilizing positive adaptation strategies. In other words, through the positive interaction of recognition struggle, he negotiated with the mainstream society and established his identity through positive experiences. In addition, through group activities, we have endeavored to protect the rights of the individual as well as the whole society and to improve the image and to integrate with the mainstream society. Through this reconstruction of life history, we can understand the life situation of Chinese leaders and know about the qualities they want to receive in Korean society. Therefore, it is suggested that this reconstruction of life history implies social welfare practice.

• Korea Trade Review
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• v.42 no.2
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• pp.369-390
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• 2017

The view of social responsibility activities from the pioneer studies found that most research is mainly limited to the corporate social responsibility activities. The related studies on the individual level are very few. Therefore, it is very necessary to make a clearer and more systematic empirical research for the global companies whose employees are directly involved in the companies' social responsibility activities. In order to find the relationship between variables, we collected data from chinese employee of Korean firms which located in China. The result of empirical test is as follows; First, the social responsibility activities of the individual level have a significant positive effect on the employees' job satisfaction and organization inputs. In other words, social responsibility activities could improve the employee's job satisfaction and organization inputs. Second, innovative organizational culture of South Korean companies has a significant positive effect on the individual level social responsibility activities. Third, transformational leadership of the CEO in South Korean have no effect on personal level social responsibility activities. Fourth, the CEO'S ethical values have great positive effect on personal level of social responsibility activities. Through the analysis we can see, in the process of global corporate implicating social responsibility activities, the CEO'S ethical values are more important than the transformational leadership of the CEO. Finally, in the relationship between the employees' personal ethical values and personal social responsibility activities, the employees' personal ethical values in South Korean companies have great positive effect on the personal level social responsibility activities.

• Korea Trade Review
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• v.43 no.5
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• pp.25-45
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• 2018

This paper estimates the export losses of the Korean domestic automobile industry due to US trade pressure and its economic ripple effects. Using the HS 6 digit tariff and export data from 2010 to 2017, this paper estimates the tariff elasticity of Korea's US automobile exports against a US tariff increase by applying the Poisson Pseudo maximum likelihood estimation method. After estimating Korea's export losses to the US in three trade pressure scenarios, we estimate its impact on Korean domestic production, value-added and job creation by applying the tariff impact accumulation model based on the industry input-output analysis. Empirical results show that the impact of 25% global tariff by the US on the Korean domestic economy is estimated to result in $30.8 billion in export losses for the five years from 2019 to 2023, about 300 thousand job losses, 88.0 trillion in production inducement losses, and 24.0 trillion in value-added inducement losses. The impacts of withdrawal of the automobile tariff concession are estimated at $4.27 billion export losses and 41.7 thousand job losses. A 15% tariff rate on automobile parts for 3 years is estimated to result in $1.93 billion export losses and 18.7 thousand job losses.

• Korea Trade Review
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• v.42 no.5
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• pp.43-69
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• 2017

The study examined moderating role of thinking style about causality in the relationship between the perceived brand globalness(PBG) and the brand evaluation. Thinking style about causality is divided into interactionism and dispositionism. Individualism culture shows a tendency of thinking style about causality to dispositionism, and collectivist cultures shows a tendency for interactionism. We conducted a survey on Korean college students who represent collectivist cultures and foreign students from countries of individualistic culture and analyzed data through structural equation modeling. Analysis result showed that the higher the respondents perceived PBG, the higher they perceived brand quality, brand quality, and brand price. However, it showed that PBG has greater positive effects on perceived brand quality and perceived brand reputation among Korean students than students from individualistic cultures. On the other hand, the effects of PBG on perceived brand price did not show any significant difference between Korean students and students from individualist cultures. Thus, we can conclude that thinking style about causality plays a moderating role in the relationship between PBG and perceived brand quality and brand reputation, while it does not do so between PBG and perceived brand price.