• Journal of Satellite, Information and Communications
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• v.2 no.2
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• pp.29-35
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• 2007

COMS satellite is a multipurpose satellite in the geostationary orbit, which accommodates multiple payloads of the Ka band Satellite Communication Payload, Meteorological Imager, and Geostationary Ocean Color Imager into a single spacecraft platform. In this paper, Korea's first innovative geostationary Communication, Ocean and Meteorological Satellite (COMS) program is introduced which is fully funded by Korean Government. The satellite platform is based on the Astrium EUROSTAR 3000 communication satellite, but creatively combined with MARS Express satellite platform to accommodate three different payloads efficiently for COMS. The goals of the Ka band satellite communication mission are to in-orbit verify the performances of advanced communication technologies and to experiment wide-band multi-media communication service. The Meteorological Imager mission is to continuously extract meteorological products with high resolution and multi-spectral imager, to detect special weather such as storm, flood, yellow sand, and to extract data on long-term change of sea surface temperature and cloud. The Geostationary Ocean Color Imager mission aims at monitoring of marine environments around Korean peninsula, production of fishery information (Chlorophyll, etc.), and monitoring of long-term/short-term change of marine ecosystem. The system design difficulties are in the different kinds of payload mission requirements of communication and remote sensing purposes and how to combine them into one to meet the overall satellite requirements. In this paper, Ka band communication payload system is more highlighted.

• Journal of Digital Convergence
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• v.12 no.7
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• pp.133-145
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• 2014

Recently, Hospital information systems have the large databases by wide range offices for hospital management, health care to improve the quality of care. However, hospital information systems for information security measures are insufficient. Therefore, when we construct the hospital information system, we have to audit the information security measures for them, and we have to manage the ISMS(Information Security Management System) to maintain the information protection level through the risk managements. In this paper, we suggested the hospital information security audit model for the protection of health information privacy by the current hospital information systems, information security management system(ISMS), and hospital information security requirements and threats. We derived the check items compared with ISO27799 reflected the characteristics of the hospital. We classified the security domains as the physical, technical, administrative domain, and derived the check items for information security. We also designed the check lists by mapping the ISO27799 risk management process to improve the security and efficiency simultaneously. Our model by the five-point scale survey of IT experts was verified the suitability with the average of 4.91 points.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.7
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• pp.118-127
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• 2010

Current TCP/IP-based Internet architecture has been used for over 30 years, however it will confront with fundamental problems due to new protocol extension limitation since communication environments will change drastically and various user requirements will be emerging in near future. To solve these problems, major countries have started Future Internet researches based on clean slate approach and they will deploy large-scale testbed to experiment and verify new functions. OpenFlow switch technology has been proposed as a new experimental technology for independent protocol that can utilized the legacy network devices and does not interfere with the production Internet traffic. Korea also started Future Internet testbed project called FIRST and OpenFlow switch with NetFPGA card will be used to deploy this testbed. To interconnect distributed testbed using OpenFlow switches, logical tunnel should be established by encapsulating MAC frame inside a unicast IP packet between OpenFlow switches because OpenFlow switches are not directly connected. In this paper, we have implemented a NetFPGA-based that performs MAC in IP tunneling between various OpenFlow switch sites implemented in domestic research network KOREN. The performance evaluation shows that the NetFPGA-based capsulator reveals better performance than the software-based tunneling and it can be utilized as a testbed for experimentation of Future Internet technologies.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.3
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• pp.20-40
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• 2003

Since unloaded Q-value of a high-temperature superconductor(HTS) filter is very high, a bandpass filter(BPF) and a lowpass filter(LPF) with an increase of pole numbers can be fabricated without an increase of an insertion loss(IL) ; recently a 70-pole BPF is developed in USA. They have an abrupt skirt property and an excellent attenuation level for out-of band. Moreover, they can be miniaturized when lumped element resonators or the slow-wave characteristic are used. Technology of fabricating a HTS epitaxial film as well as a film of a 4 inch area also makes the planar type filter with a various structure and an enhanced power handling capability possible. Recently, the HTS filter subsystems composed of a planar-type HTS filters, a GaAs-based LNA and a mini-cryocooler are developed. The extended receiver front- end subsystems for mobile radio communications decrease the noise-figure level of the communication system and the frequency interference interacted adjacent bands, and increase the efficiency of frequency and the capacity of communication system. In this paper, theory for developing the HTS filter, its kinds, its design rules, its characteristics are reviewed. The feature of the research and market trends related to the HTS filter systems for the receiver front-end subsystem of mobile base station are surveyed.

• Information Systems Review
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• v.12 no.2
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• pp.189-203
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• 2010

Is presenting guidance of information performance measurement as government PRM version 2.0 these common reference models in public sector. Government PRM is consisted of assessment classification system and standard line of sight and performance management standard form. Through this, is sorting performance element and define cause-and effect. Government PRM is supplying measurement categories at assessment classification system, but relative importance for application standard by measurement categories is not presenting. In this study, importance for government PRM's measurement categories been applying by commonness Test of information performance measurement of public sector wishes to deduce estimation and priority. Research model used Fuzzy QFD, and designed so that can reflect well PRM's development purpose. I applied Fuzzy AHP and FPP method that graft together fuzzy theory to minimize uncertainty and ambiguity in that expert opinion. Is drawn to element that "Standard model offer for information department and management" is the most important in government PRM's development purpose. "Quality of service" is showing the highest priority in customer results in measurement category. Importance for government PRM's measurement categories can offer common valuation basis in government and public institution. Hereafter if examine closely quantitative cause-and effect for structure model of measurement classification system when study government PRM more objective and efficient reference model become.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.382-390
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• 2018

This study developed a model to evaluate the quality management system of a medical device manufacturing company, and applied it to medical device manufacturers to understand the impact on business performance in response to international regulations and industry's change. This study prepared preliminary items, defined four (4) major factors (Plan-Do-Check-Act) that consist of the evaluation layers and items per category according to prior research review and expert interview, and calculated the weight and importance using AHP. The study results showed that responsibility & authority and quality objective in Planning Category, product-related requirement and R&D in Doing Category, Measuring and monitoring in Check Category, and review of meeting Regulatory and regulation in Action Category are relatively more important factors. The evaluation model developed based on the calculated weight and importance to business performance was applied to medical device manufacturers to investigate and analyze the implementation level of QMS and its impact on business performance according to each category. Most medical device manufacturers to be studied showed a reasonable level of QMS and effective business performance. Almost all the evaluation layers and items in the four (4) factors had a significant influence on business performance. Although the medical device quality management system is aimed mainly at license acquisition, it is important that management environment factors not related directly to licensing and authorization are important to business performance, and it is effective when these factors are integrated and operated within and outside the manufacturer.

• Korean Journal of Construction Engineering and Management
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• v.17 no.1
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• pp.10-17
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• 2016

Domestic CM market has continued to grow since the enactment of CM policies in 1996. In addition, future CM market is forecasted to have potential high growth. Therefore, it is necessary to apply various CM business models reflecting the owner's requirements and characteristics in order to improve in the CM industry and to strengthen the competitiveness in the overseas construction market. In this context, the purpose of this study is to suggest strategies of various CM applications based on comparison of 4 cases analyzed by 'business weight' and 'business depth' in terms of business function as well as by the types of 'CM market' and 'CM practice'. Result of this comparative analysis shows that each case presents differences in terms of type, business weight, and business depth of CM practice. However, domestic public CM services are currently being challenged to strengthen capability throughout the project life-cycle against the limitation of government's CM policies focused on the construction supervision. In order to address this problem, this study proposes the strategies of various CM applciations from several different perspectives

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.11C
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• pp.1064-1073
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• 2002

In this paper, we design and implement the Wireless Transaction Protocol (WTP) proposed by the Wireless Application Protocol (WAP) forum using a protocol development tool, SDL Development Tool (SDT). And we conduct a comparative performance evaluation of the WTP implementation with other three implementations that are based on different implementation models respectively: the server model, the coroutine model, and the activity-thread model. To implement WTP, we first use Unified Modeling Language (UML) for analyzing the protocol requirement and defining the protocol engine architecture. Next, we use Software Development Language (SDL) to design the protocol engine in details and then generate the WTP implementation automatically with the aid of SDT The code size of the WTP implementation generated by SDT is 62% larger than the other three implementations. However, its throughput and system response time for transaction processing is almost equal to the other three implementations when the number of concurrent clients is less than 3,000. If more than 5,000 concurrent clients tries, the transaction success rate abruptly decreases to 10% and system response time increases to 1,500㎳, due to the increased protocol processing time. But, it comes from the fact that the load overwhelms the capacity of the PC resource used in this experimentation.

• Journal of the Institute of Convergence Signal Processing
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• v.12 no.4
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• pp.274-280
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• 2011

Due to their rapid growth and new paradigm applications, wireless sensor networks(WSNs) are morphing into low power personal area networks(LoWPANs), which are envisioned to grow radically. The fragmentation and reassembly of IP data packet is one of the most important function in the 6LoWPAN based communication between Internet and wireless sensor network. However, since the 6LoWPAN data unit size is 102 byte for IPv6 MTU size is 1200 byte, it increases the number of fragmentation and reassembly. In order to reduce the number of fragmentation and reassembly, this paper presents a new scheme that can be applicable to 6LoWPAN. When a fragmented packet header is constructed, we can have more space for data. This is because we use 8-bits routing table ill instead of 16-bits or 54-bits MAC address to decide the destination node. Analysis shows that our design has roughly 7% or 22% less transmission number of fragmented packets, depending on MAC address size(16-bits or 54-bits), compared with the previously proposed scheme in RFC4944. The reduced fragmented packet transmission means a low power consumption since the packet transmission is the very high power function in wireless sensor networks. Therefore the presented fragmented transmission scheme is well suited for low-power wireless sensor networks.

• The Journal of the Korea Contents Association
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• v.15 no.6
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• pp.33-42
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• 2015

As smart phones have been increasingly used to access information with bigger screens and higher resolution, smart phones have rapidly grown larger. Even Apple which had stuck to the 4-inch smart phone screen size, released 5.5-inch iPhone 6 plus. In this trend of smart phone enlargement, manufacturers have mostly incorporated one-handed modes to 5-inch or larger phones to keep the convenience of one-handed operation. But most of them provide just smaller screens and are rather complicated to set up after several menus to touch. In this study, this research examined one-handed functions of each smart phone manufacturer to understand problems in the one-handed smart-phone manipulation of web-browsing which is one of the frequent smart phone services. And by investigating smart phone users, this research found out requirements for one-handed web search operation. Based on this examination, the author of this research designed an efficient one-handed interface for mobile web-search without reducing the screen size. Then, to assess the possible usability improvement, the prototype was applied to a large 5.5-inch-screen smart phone to evaluate its performance through observation and surveys and find out manipulation satisfaction and further improvements.