• Journal of the Korean Society of Radiology
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• v.13 no.7
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• pp.901-907
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• 2019

The aim of this study is to evaluate the ability of target localizations of Leksell GammaPlan(LGP) in Gamma Knife Subthalamotomy(or Pallidotomy, Thalamotomy) of functional diseases. To evaluate the accuracy of LGP's location settings, the difference Δr of the target coordinates calculated by LGP (or LSP) and author's algorithm was reviewed for 10 patients who underwent Deep Brain Stimulation(DBS) surgery. Δr ranged from 0.0244663 mm to 0.107961 mm. The average of Δr was 0.054398 mm. Transformation matrix between stereotactic space and brain atlas space was calculated using PseudoInverse or Singular Value Decomposition of Mathematica to determine the positional relationship between two coordinate systems. Despite the precise frame positioning, the misalignment of yaw from -3.44739 degree to 1.82243 degree, pitch from -4.57212 degree to 0.692063 degree, and rolls from -6.38239 degree to 7.21426 degree appeared. In conclusion, a simple in-house algorithm was used to test the accuracy for location settings of LGP(or LSP) in Gamma Knife platform and the possibility for Gamma Knife Subthalamotomy. The functional diseases can be treated with Gamma Knife Radiosurgery with safety and efficacy. In the future, the proposed algorithm for target localizations' QA will be a great contributor to movement disorders' treatment of several Gamma Knife Centers.

• The Journal of Engineering Geology
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• v.28 no.2
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• pp.207-215
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• 2018

Almost all countries of the world have recently made great efforts to reduce green-house gases to alleviate the global warming threatening human survival, because a huge amount of carbon dioxide as one of the main green-house gases has been emitted from the combustion processes of fossil fuels such as coal and oil. $CO_2$ capture and storage (CCS) technology is a representative method to diminish the green-house gases, and actively investigated by many countries. This study focuses on the design and construction of a high pressure $CO_2$ injection facility to store it to underground, which is the first $CO_2$ injection in Korea following the steps of the $CO_2$ capture from large $CO_2$ emission sources and transportation to the sea. Injection tests of $CO_2$ on the platform on the sea were carried out in Yeongil Bay of Pohang city in the early 2017. Thus, we were able to perceive the necessary operating conditions of the injection facility, injection characteristic, and knowhow of the injection facility. The results obtained from the injection test shall be utilized for facility upgrades and scale-ups.

• Journal of the Korean Regional Science Association
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• v.35 no.3
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• pp.59-76
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• 2019

This study aims to develop urban scenarios for future cities and validate the future city scenarios using a Delphi method. The scenarios of future city was derived from urban structure, land use, transportation, and urban infrastructure and development using big data analysis, environmental scanning techniques, and literature review. The Delphi survey interviewed 24 erudite scholars and experts across 6 nations including Korea, USA, UK, Japan, China, Australia and India. The Delphi survey structure was designed to test future city scenarios, verified by the 5-point Likert scale. The survey also asked the timing of each scenario likely happens by the three terms of near-future, mid-future and far-future. Results of the Delphi survey reveal the following points. Firstly, for the future urban structure it is anticipated that urban concentration continues and higher density living in global mega cities near future. In the mid-future small and medium size cities may decrease. Secondly, the land use pattern in the near-future is expected of increasing space sharing and mixed or layered vertical land-use. In addition underground space is likely to be extended in the mid-future. Thirdly, in the near-future, transport and infrastructure was expected to show ICT embedded integration platform and public and private smart transport. Finally, the result of Delphi survey shows that TOD (Transit Oriented Development) becomes a development norm and more emphasis on energy and environment fields.

• The Journal of Industrial Distribution & Business
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• v.10 no.1
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• pp.59-67
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• 2019

Purpose - The Millennial Generation, which grew in the wake of the spread of the Internet and rapid changes in the media environment, is rapidly moving from the traditional broadcasting environment to the Internet-broadcasting environment in terms of content acceptance. With the emergence of UGC (User-generated content), the change in the status of single-person content creators enables the growth of multi-channel networks (MCN), a new content-distribution platform and an agency concept for single creators. Youtube-based MCN produces multiple single star producers and casts and provides its own video series through Youtube. It is also emerging as a major M&A target for global media providers in terms of providing content to a wide range of consumers with the same interests and consumption characteristics. In addition, for the Millennials generation, which are part of their lives, MCN is becoming the most suitable media for TGIF (Twitter, Google, i-phone, Facebook). Accordingly, this study defines newly emerging MCNs and analyzes the factors for accepting MCN-produced content based on the push-pull-mooring (PPM) model. Research design, data, and methodology - An empirical analysis is performed through a questionnaire survey. For this purpose, 204 people who have experience of watching MCN were studied. Collected data is processed through analysis of a structural equation model using R to test the hypothesis. Results - For the MCN service to become an alternative to existing media, it is necessary to continuously promote cultural diversity and diversity of attempts that conventional media cannot provide. It is the attractiveness of the alternative that has the greatest influence on the intention to switch to a MCN service. When we look at MCN content so far, certain patterns such as game progress, introduction, food, and chat rooms have already appeared. We need to overcome this and develop a completely new conceptual content that we have never seen before. This requires a more generous viewer perception of the topics covered. For diversity, linguistic and verbal violence should be tolerant in common sense to provide a foundation for securing cultural diversity. Conclusions - In this study, we tried to develop a comprehensive approach to the substitution effect of MCN. In terms of academic achievement, the PPM model is used to enhance the utilization of media and broadcasting. Practical implications are to provide an analytical framework for verifying alternative or complementary effects when viewers switch to MCN.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.75-84
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• 2018

Increasing the operation rate of components and stabilizing the operation through timely management of the core parts are crucial for improving the efficiency of the railroad maintenance industry. The demand for diagnosis technology to assess the condition of rolling stock components, which employs history management and automated big data analysis, has increased to satisfy both aspects of increasing reliability and reducing the maintenance cost of the core components to cope with the trend of rapid maintenance. This study developed a big data platform-based system to manage the rolling stock component condition to acquire, process, and analyze the big data generated at onboard and wayside devices of railroad cars in real time. The system can monitor the conditions of the railroad car component and system resources in real time. The study also proposed a machine learning technique that enabled the distributed and parallel processing of the acquired big data and automatic component fault diagnosis. The test, which used the virtual instance generation system of the Amazon Web Service, proved that the algorithm applying the distributed and parallel technology decreased the runtime and confirmed the fault diagnosis model utilizing the random forest machine learning for predicting the condition of the bearing and wheel parts with 83% accuracy.

• KIISE Transactions on Computing Practices
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• v.23 no.5
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• pp.284-292
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• 2017

With the development of Internet of Things (IoT) technology, the combination of ICT and medical services has been increasing to improve the quality of medical services. Using the IoTs, we can collect personal health information continuously in a patient's everyday life. We expect that this will improve the quality of medical service through analysis. However, the problem of ensuring the protection of personal information within the personal health information has been hampering the research, development, and application of such services. Other problems include lack of IoT devices and lack of user convenience for collecting health information about a patient's everyday life. Therefore, in this study, we construct a daily health information management service that can collect the health related information at any time and store this data in personal storage. This data is then only provided to the healthcare worker when necessary. We built a test bed for an IoT-based smart home platform and are currently conducting user experiments. Based on the results of this study, we are attempting to provide a high quality medical trial service based on daily health information through linkage with medical device manufacturers, medical clinics, insurance companies, etc. We expect the proposed health information management service will contribute to the revitalization of smart health care services via activating various health related IoT devices and analyzing daily health information.

• Journal of Astronomy and Space Sciences
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• v.20 no.4
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• pp.339-350
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• 2003

Engineering qualification model payload for a communications and broadcasting satellite(CBS) was developed by ETRI from May, 2000 to April, 2003. For. the purpose of functional test and verification of the payload, a real-time hardware-in-the-loop(HITL) CBS simulator(CBSSIM) was also developed. We assumed that the spacecraft platform for the CBSSIM is a geostationary communication satellite using momentum bias three-axis stabilization control technique based on Koreasat. The payload hardware is combined with CBSSIM via Power, Command and Telemetry System(PCTS) of Electrical Ground Support Equipment(EGSE). CBSSIM is connected with PCTS by TCP/IP and the payload is combined with PCTS by MIL-STD-1553B protocol and DC harness. This simulator runs under the PC-based simulation environment with Windows 2000 operating system. The satellite commands from the operators are transferred to the payload or bus subsystem models through the real-time process block in the simulator. Design requirements of the CBSSIM are to operate in real-time and generate telemetry. CBSSIM provides various graphic monitoring interfaces and control functions and supports both pre-launch and after-launch of a communication satellite system. In this paper, the HITL simulator system including CBSSIM, communications payload and PCTS as the medium of interface between CBSSIM and communications payload will be described in aspects of the system architecture, spacecraft models, and simulator operation environment.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.1
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• pp.29-37
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• 2009

Recently, message based data transmission plays an important role in modem computing systems. Especially JMS(Java Message Service) is one of the most popular messaging platform. However, because of its characteristics for maintaining reliability, if we want to use it for transmission of large scale messages in a distributed Internet environment by using a WAN connection which may not be robust enough, we need to employ a different method to minimize total transmission time of messages. We found the fact that the total time of message transmission heavily depends on size of a message. In order to achieve the ideal size of a message, we develope a novel mechanism and a system which finds the ideal size of a message and automatical1y control JMS applications for minimizing transmission time. Finally, we test the proposed mechanism and system using real-data in order to prove advantages and compared with the naive mechanism. As a conclusion, we showed that our proposed mechanism and system provide an effective way to reduce transmission time of large scale messages in distributed environment.

• The Journal of Information Systems
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• v.26 no.4
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• pp.247-284
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• 2017

Purpose The first purpose of this study is to investigate factors that are likely to influence user's intention to adopt third-party mobile payment platform. A comprehensive study about mobile payment services have used various variables to explain user's use intention based on the theory of reasoned action (TRA) or the theory of planned behavior (TPB). Variables such as simplicity, security, costs, relative advantage, individual mobility, subjective norm, trust, satisfaction, attitude towards use, perceived usefulness, perceived ease of use and so on. Among these factors, we expect to find out the most influential factors effecting user's use intention of the third-party mobile payment services. Second, we also examine whether the most influential factors have the same influence to different third-party mobile payment services by conducting comparative study of Alipay and WeChat Pay. Design/methodology/approach Empirical data for this study were collected from Chinese who has the experience using or have used Alipay or WeChat Pay. Participants needed to be familiar with Alipay or WeChat Pay because such users may be more aware of both the advantages and disadvantages of Alipay and WeChat Pay. We conduct a pilot test using Smart PLS 2.0, which includes 50 Alipay users and 82 WeChat Pay users. The result indicates that all the measurement fit for the context. And then 980 questionnaires were mainly sent out to the college students and the e-mails users randomly. To encourage participation, we give the participants a small gift as a present. Finally, we received a total of 683 replied. Data from respondents who gave incomplete or invalid answers were excluded to assure the validity of the constructs. 79 questionnaires were rejected, finally the valid data are 604 (with 372 Alipay users and 232 WeChat Pay users). Findings The results suggest that users' intention is determined by their trust on third-party mobile payment service and perceived usefulness of use. Comparative study results also indicated that the factors have different influence on Alipay group and WeChat Pay group, which offers a new aspect for academic field, and provides useful information to mobile payment service providers in China.

• Journal of Korea Port Economic Association
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• v.36 no.1
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• pp.141-164
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• 2020

With business environments around the world facing uncertainty and complexity, companies have focused on supply chain management as one of the essential elements in securing a competitive advantage. Successful supply chain management requires internal efforts to strengthen the core competencies of the company and the integration of individual functions in the supply chain. This study aims to investigate the effect of information sharing between companies on supply chain integration and corporate performance. The research hypothesis established in previous studies was analyzed using structural equation modeling. A total of 723 questionnaire responses were used to test the hypotheses of this study. We found that the integration and sharing of information between companies have a great influence on supply chain integration, which has positive effects on corporate performance at the operational and strategic levels, including finance, market share, and customer satisfaction. The integration of supply chains via information integration and sharing between companies can promote the flow of information, services, goods, and money. Therefore, if information is disconnected between actors in the supply chain, it will lead to negative effects on the management of the entire supply chain. On the other hand, if supply chain actors can share information efficiently in real time on one platform, they can expect to optimize the entire supply chain. Information sharing and integration at the strategic and operational levels play a vital role in supply chain integration, which contributes to achieving a company's performance targets and enhancing its competitiveness.