• Journal of Computing Science and Engineering
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• v.7 no.3
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• pp.168-176
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• 2013

Long-term evolution (LTE) is emerging as a major candidate for 4G cellular networks to satisfy the increasing demands for mobile broadband services, particularly multimedia delivery. Multiple-input multiple-output (MIMO) technology combined with orthogonal frequency division multiple access and more efficient modulation/coding schemes (MCS) are key physical layer technologies in LTE networks. However, in order to fully utilize the benefits of the advances in physical layer technologies, the MIMO configuration and MCS need to be dynamically adjusted to derive the promised gains of 4G at the application level. This paper provides a performance evaluation of video traffic with variations in the physical layer transmission parameters to suit the varying channel conditions. A quantitative analysis is provided using the perceived video quality as a video quality measure (evaluated using no-reference blocking and blurring metrics), as well as transmission delay. Experiments are performed to measure the performance with changes in modulation and code rates in poor and good channel conditions. We discuss how an adaptive scheme can optimize the performance over a varying channel.

• Animal Systematics, Evolution and Diversity
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• v.17 no.2
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• pp.245-250
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• 2001

Two new species of the genus Psammocinia (Dictyoceratida, Irciniidae), P. bergquisti n. sp. and P. gageoensis n. sp., are described from Gageodo Island (Sohuksando Island), Korea. P. bergquisti n. sp. is characterized by the thumb like appearance and secondary fibre which makes a broad plate or secondary web while other known species in Psammocinia has many narrow and simple secondary fibres. P. gageoensis n. sp. is very similar to P. mosulpia Sim 1998 in shape, but primary fibre of the new species has more complex fascicles and it is difficult to see the detritus in the fibre. The primary fibre of this new species is cored with the smaller sand than that of P. mosulpia.

• Journal of The Korean Astronomical Society
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• v.40 no.4
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• pp.165-169
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• 2007

The numerical simulations associated with the interaction of High Velocity Clouds (HVC) with the Magnetized Galactic Interstellar Medium (ISM) are a powerful tool to describe the evolution of the interaction of these objects in our Galaxy. In this work we present a new project referred to as Theoretical Virtual i Observatories. It is oriented toward to perform numerical simulations in real time through a Web page. This is a powerful astrophysical computational tool that consists of an intuitive graphical user interface (GUI) and a database produced by numerical calculations. In this Website the user can make use of the existing numerical simulations from the database or run a new simulation introducing initial conditions such as temperatures, densities, velocities, and magnetic field intensities for both the ISM and HVC. The prototype is programmed using Linux, Apache, MySQL, and PHP (LAMP), based on the open source philosophy. All simulations were performed with the MHD code ZEUS-3D, which solves the ideal MHD equations by finite differences on a fixed Eulerian mesh. Finally, we present typical results that can be obtained with this tool.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.7
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• pp.2815-2839
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• 2020

In a cloud computing paradigm, allocation of various virtualized ICT resources is a complex problem due to the presence of heterogeneous application (MapReduce, content delivery and networks web applications) workloads having contentious allocation requirements in terms of ICT resource capacities (resource utilization, execution time, response time, etc.). This task of resource allocation becomes more challenging due to finite available resources and increasing consumer demands. Therefore, many unique models and techniques have been proposed to allocate resources efficiently. However, there is no published research available in this domain that clearly address this research problem and provides research taxonomy for classification of resource allocation techniques including strategic, target resources, optimization, scheduling and power. Hence, the main aim of this paper is to identify open challenges faced by the cloud service provider related to allocation of resource such as servers, storage and networks in cloud computing. More than 70 articles, between year 2007 and 2020, related to resource allocation in cloud computing have been shortlisted through a structured mechanism and are reviewed under clearly defined objectives. Lastly, the evolution of research in resource allocation techniques has also been discussed along with salient future directions in this area.

• Journal of Broadcast Engineering
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• v.13 no.5
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• pp.752-759
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• 2008

The latest convergence of broadcasting and communication makes the boundary between medias be ambiguous. It pursues the new type of culture that the unspecified many participants seek the satisfaction for the same target in an realtime environment. ARG(Alternative Reality Game) is a new alternate real game created by media convergence and it processes the more realistic interactivity between users through ARS, SMS, BLOG, Cafe and Messages. This paper analyzes the implementation, design, and construction schemes of ARG in the side of the human thinking and media. We also propose the evolution and role of the broadcasting by combining broadcasting for the activation of ARG.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.8
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• pp.3606-3629
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• 2018

The discovered high potential utility itemsets (HPUIs) have significant influence on a variety of areas, such as retail marketing, web click analysis, and biological gene analysis. Thus, in this paper, we propose an algorithm called HPUIM-QGA (Mining high potential utility itemsets based on a quantum genetic algorithm) to mine HPUIs over uncertain datasets based on a quantum genetic algorithm (QGA). The proposed algorithm not only can handle the problem of the non-downward closure property by developing an upper bound of the potential utility (UBPU) (which prunes the unpromising itemsets in the early stage) but can also handle the problem of combinatorial explosion by introducing a QGA, which finds optimal solutions quickly and needs to set only very few parameters. Furthermore, a pruning strategy has been designed to avoid the meaningless and redundant itemsets that are generated in the evolution process of the QGA. As proof of the HPUIM-QGA, a substantial number of experiments are performed on the runtime, memory usage, analysis of the discovered itemsets and the convergence on real-life and synthetic datasets. The results show that our proposed algorithm is reasonable and acceptable for mining meaningful HPUIs from uncertain datasets.

• The Journal of the Korea Contents Association
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• v.10 no.12
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• pp.77-83
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• 2010

Recently, IT-based environment is changing rapidly as changing in web services platform, evolution of cloud computing environments and expanding the base of a smart market. Accordingly, monitoring development of environment is changing quickly. So a customizable SaaS-based monitoring tool is required to provide monitoring services. It has to support a variety of environmental monitoring and a resource managers with requested information, and by an enhanced monitoring framework in clouding environment of management system. In this paper, the 3D viewer for the management of sensor node management system was designed and built. Through the 3D viewer by enhancing the accessibility and visibility, the sensor network will allow resources to be used efficiently.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.149-150
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• 2015

Today, rapid evolution of information communication technology occurring in Korea has extensive influence on our daily life, and increasing awareness about the user experience. As the connected Internet information systems increases, one of the problems happening between users and information systems such as Internet shopping-malls, portal sites, and corporate web sites is related with the information privacy concerns issues. In this research, we aim to analyze factors influencing of the invasion of privacy on intention to use in e-commerce environment. Based on these findings, several theoretical and practical implications were suggested and discussed. Thus, we have reviewed extensive previous studies on information privacy in local and foreign information systems, marketing and other fields. The purpose of this study is to provide future directions of studies on information privacy concerns by analyzing past and recent trends of the studies.

• Journal of Information Technology Services
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• v.15 no.4
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• pp.41-62
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• 2016

In Internet of Things (IoT) era, more diverse types of information are collected and the environment of information usage, distribution, and processing is changing. Recently, there have been a growing number of cases involving breach and infringement of personal information in IoT services, for examples, including data breach incidents of Web cam service or drone and hacking cases of smart connected car or individual monitoring service. With the evolution of IoT, concerns on personal information protection has become a crucial issue and thus the risk analysis and management method of personal information should be systematically prepared. This study shows risk factors in IoT regarding possible breach of personal information and infringement of privacy. We propose "a risk analysis framework of protecting personal information in IoT environments" consisting of asset (personal information-type and sensitivity) subject to risk, threats of infringement (device, network, and server points), and social impact caused from the privacy incident. To verify this proposed framework, we conducted risk analysis of IoT services (smart communication device, connected car, smart healthcare, smart home, and smart infra) using this framework. Based on the analysis results, we identified the level of risk to personal information in IoT services and suggested measures to protect personal information and appropriately use it.

• Genomics & Informatics
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• v.16 no.4
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• pp.28.1-28.6
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• 2018

Due to the increasing interest in synonymous codons, several codon bias-related terms were introduced. As one measure of them, the tRNA adaptation index (tAI) was invented about a decade ago. The tAI is a measure of translational efficiency for a gene and is calculated based on the abundance of intracellular tRNA and the binding strength between a codon and a tRNA. The index has been widely used in various fields of molecular evolution, genetics, and pharmacology. Afterwards, an improved version of the index, named specific tRNA adaptation index (stAI), was developed by adapting tRNA copy numbers in species. Although a subsequently developed webserver (stAIcalc) provided tools that calculated stAI values, it was not available to access pre-calculated values. In addition to about 100 species in stAIcalc, we calculated stAI values for whole coding sequences in 148 species. To enable easy access to this index, we constructed a novel web database, named STADIUM (Species-specific tRNA adaptive index compendium). STADIUM provides not only the stAI value of each gene but also statistics based on pathway-based classification. The database is expected to help researchers who have interests in codon optimality and the role of synonymous codons. STADIUM is freely available at http://stadium.pmrc.re.kr.