• Information Systems Review
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• v.10 no.2
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• pp.235-251
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• 2008

With the successful arrival of quality free/open source software, open source ISD(Information System Development) projects have been drawing attention from academic researchers. However, there have been few efforts to examine the managerial aspect of open source ISD projects. This study use a case research methodology to explores the management of open source projects, especially from the perspective of behavior control. Through data analysis and discussion, the study found that various practices related to behavior control were exercised to obtain participants' shared goals, although specific instances vary in each case. This finding is contradictory to the views of some researchers who suggested open source ISD projects lack behavior control. For more comprehensive understanding, however, future research should also include controls of open source projects in terms of outcome control and self-control.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.59.1-59.1
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• 2016

Blue Straggler Stars(BSS) affect their host star cluster in various parameters like color, dynamics, etc. For this reason, it is important to know how to relate BSS frequency and evolution of their host stellar system. To statistical study about global properties of open clusters as the environments of BSS formation, we use three catalogues - (1) two galactic open clusters catalogues including BSS candidate, (2) Milky Way Star Cluster (MWSC) survey data. Then, we compare with the data of two BSS catalogues for test of the result of Marchi et al. 2006. We also investigate the radial mass distribution in open cluster, because it is possible that changing the gradient of radial mass distribution cause increasing the BSS frequency. When we group the open cluster into having BSS or not and other criteria, the groups show slight discrepancies, but we show some important results.

• Korean Journal of Computational Design and Engineering
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• v.17 no.1
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• pp.7-16
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• 2012

One distinguishing feature of BIM(Building Information Modeling) is the objectification of spatial elements independently, which makes it easy to represent spatial network. From this perspective, this study aimed to develop the spatial network analysis tool based on open BIM technologies. From the literature review, an object model of spatial network with nodes and links and a process model from construction to visualization were established. A prototype system implementing the proposed models, named SNAT(Spatial Network Analysis Tool), was developed in Java platform with using its open source packages. SNAT can create a spatial network from IFC-BIM model, calculate the indices of spatial network analysis, and visualize it with the representing types(map, graph, matrix and table).

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.11
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• pp.4224-4243
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• 2021

Cognitive radio (CR) is a feasible intelligent technology and can be used as an effective solution to spectrum scarcity and underutilization. As the key function of CR, cooperative spectrum sensing (CSS) is able to effectively prevent the harmful interference with primary users (PUs) and identify the available spectrum resources by exploiting the spatial diversity of multiple secondary users (SUs). However, the open nature of the cognitive radio networks (CRNs) framework makes CSS face many security threats, such as, the malicious user (MU) launches Byzantine attack to undermine CRNs. For this aim, we make an in-depth analysis of the motive and purpose from the MU's perspective in the interweave CR system, aiming to provide the future guideline for defense strategies. First, we formulate a dynamic Byzantine attack model by analyzing Byzantine behaviors in the process of CSS. On the basis of this, we further make an investigation on the condition of making the fusion center (FC) blind when the fusion rule is unknown for the MU. Moreover, the throughput and interference to the primary network are taken into consideration to evaluate the impact of Byzantine attack on the interweave CR system, and then analyze the optimal strategy of Byzantine attack when the fusion rule is known. Finally, theoretical proofs and simulation results verify the correctness and effectiveness of analyses about the impact of Byzantine attack strategy on the throughput and interference.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.8
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• pp.3992-4005
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• 2018

In our current information-based society in which knowledge is a fundamental asset to production, the capability to utilize information and produce knowledge with the use of information technology (IT) has become essential to learning. Massive Open Online Courses (MOOCs) have recently been introduced in light of such changes and are recognized as an alternative to open education. MOOCs' capabilities are being acknowledged in lifelong education in terms of reeducation and knowledge sharing, and also in terms of improving teaching quality, and improving university students' levels of creativity and integrated thinking by supporting high-level content and teaching. Therefore, this study presents an extended research model that combines information system (IS) continuance and task-technology fit models. Our study researches previous literature, revealing factors of continuous use after accepting MOOCs from the learner's perspective, and analyzes the model empirically. The ideal environment for MOOCs learners is evaluated, and a strategic approach to the successful settlement and diffusion of MOOCs is presented based on this study's findings.

• Journal of Information Science Theory and Practice
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• v.8 no.2
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• pp.68-78
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• 2020

This study is a preliminary study to develop an evaluation framework necessary for evaluating the DataON platform. The first objective is to examine expert perceptions of the level of DataON platform construction. The second objective is to evaluate the importance, stability, and usability of DataON platform features over OpenAIRE features. The third objective is to derive weights from the evaluation perspective for future DataON platform evaluation. The fourth objective is to examine the preferences of experts in each evaluation perspective and to derive unbiased evaluation criteria. This study used a survey method for potential stakeholders of the DataON platform. The survey included 12 professionals with at least 10 years of experience in the field. The 57 overall functions and services were measured at 3.1 out of 5 for importance. Stability was -0.07 point and usability was measured as -0.05 point. The 42 features and services scored 3.04 points in importance. Stability was -0.58 points and usability was -0.51 points. In particular, the stability and usability scores of the 42 functions and services provided as of 2018 were higher than the total functions were, which is attributed to the stable and user-friendly improvement after development. In terms of the weight of the evaluation point, the collection quality has the highest weight of 27%. Interface usability is then weighted 22%. Subsequently, service quality is weighted 19%, and finally system performance efficiency and user feedback solicitation are equally weighted 16%.

• Nuclear Engineering and Technology
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• v.42 no.6
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• pp.608-619
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• 2010

A multi-scale analysis of water-cooled reactor thermalhydraulics can be used to take advantage of increased computer power and improved simulation tools, including Direct Numerical Simulation (DNS), Computational Fluid Dynamics (CFD) (in both open and porous mediums), and system thermalhydraulic codes. This paper presents a general strategy for this procedure for various thermalhydraulic scales. A short state of the art is given for each scale, and the role of the scale in the overall multi-scale analysis process is defined. System thermalhydraulic codes will remain a privileged tool for many investigations related to safety. CFD in porous medium is already being frequently used for core thermalhydraulics, either in 3D modules of system codes or in component codes. CFD in open medium allows zooming on some reactor components in specific situations, and may be coupled to the system and component scales. Various modeling approaches exist in the domain from DNS to CFD which may be used to improve the understanding of flow processes, and as a basis for developing more physically based models for macroscopic tools. A few examples are given to illustrate the multi-scale approach. Perspectives for the future are drawn from the present state of the art and directions for future research and development are given.

• Information and Communications Magazine
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• v.19 no.7
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• pp.56-71
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• 2002

Third generation mobile radio systems (3G) are currently being deployed in different regions of the world. Future systems beyond 3G are already under discussion in international bodies and forums such as ITU, WWRF and R&D programs of the European Union and in other regions. These systems will determine the research and standardization activities in mobile and wireless communication in the next years. Based on the experience of 3G future systems will be developed mainly from the user perspective with respect to potential services and applications including traffic demands. Therefore, the Wireless World Research Forum (WWRF) was launched in 2001 as a global and open initiative of manufacturers, network operators, SMEs, R&D centers and the academic domain. WWRF is focused on the vision of such systems the Wireless World - and potential key technologies. This paper describes the international context of activities on systems beyond third generation, the goals, objectives and structure of WWRF, the user perspective as the starting point for a future system design and the key enabling technologies for the Wireless World.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1779-1792
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• 2009

Now, the goal of the third generation KTX project is to create a new species of high speed train in order to open a new era of high speed railway system in history by authentic Korean technology and innovative design. Now the third generation KTX, must go beyond the original stagnant paradigm and be positioned as an emotional resource which is creating a shift in the public's perspective of transportation and expanding the idea that transportation intersects the two distinct realms of culture and environment as well. In addition, the overall design should reflect the Korean culture and characteristics, simple yet resonant, both the interior space and the exterior fuselage should portray the dynamic heritage of Korea such as the powerful yet subdued energy of Jung Joong Dong. In short, through the symbolic key words in Korean, Dong(Dynamics), Mek(Pulse), Ryu(Flow), Gam(Sensibility), the third generation KTX design project aims to create an new identity of Korean high speed railway which can stand globally.

• Proceedings of the KSR Conference
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• 2009.05b
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• pp.295-308
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• 2009

Now, the goal of the third generation KTX project is to create a new species of high speed train in order to open a new era of high speed railway system in history by authentic Korean technology and innovative design. Now the third generation KTX, must go beyond the original stagnant paradigm and be positioned as an emotional resource which is creating a shift in the public's perspective of transportation and expanding the idea that transportation intersects the two distinct realms of culture and environment as well. In addition, the overall design should reflect the Korean culture and characteristics, simple yet resonant, both the interior space and the exterior fuselage should portray the dynamic heritage of Korea such as the powerful yet subdued energy of Jung Joong Dong. In short, through the symbolic in Korean, Dong(Dynamics), Mek(Pulse), Ryu(Flow), Gam(Sensibility), the third generation KTX design project aims to create an new identity of Korean high speed railway which can stand globally.