• Journal of the Korean Society of Systems Engineering
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• v.12 no.2
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• pp.101-114
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• 2016

A model-based systems engineering (MBSE) approach to implementing hardware-based network cybersecurity controls for APR1400 non-safety data network is presented in this work. The proposed design was developed by implementing packet filtering and deep packet inspection functions to control the unauthorized traffic and malicious contents. Denial-of-Service (DoS) attack was considered as a potential cybersecurity issue that may threaten the data availability and integrity of DCS gateway servers. Logical design architecture was developed to simulate the behavior of functions flow. HDL-based physical architecture was modelled and simulated using Xilinx ISE software to verify the design functionality. For effective modelling process, enhanced function flow block diagrams (EFFBDs) and schematic design based on FPGA technology were together developed and simulated to verify the performance and functional requirements of network security controls. Both logical and physical design architectures verified that hardware-based cybersecurity controls are capable to maintain the data availability and integrity. Further works focus on implementing the schematic design to an FPGA platform to accomplish the design verification and validation processes.

• Journal of KIISE:Information Networking
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• v.27 no.2
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• pp.123-130
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• 2000

It is important interest for us to solve skew problem in intermedia synchronization and to solve jitter problem in intramedia synchronization. It propose multimedia synchronization model to represent mixed media which contain temporal media and spatial media, and that helps us to develop multimedia application software efficiently. The proposed paper use four parameters to deal with QoS of intermedia synchronization and relative duration time algorithm and jitter-compensatory time algorithm are presented. When key medium is destroyed we make a delay as much as maximum delay jitter of the key medium in order to playout the other medium as much as that. The result is that the application of maximum delay jitter improves the service quality.

• Structural Engineering and Mechanics
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• v.61 no.6
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• pp.693-700
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• 2017

Concrete cover cracking due to the corrosion of steel reinforcing bars is one of the main causes of deterioration in Reinforced Concrete (RC) structures. The oxidation level of the bars causes varying levels of expansion. The rebar expansions could lead to through-thickness cracking of the concrete cover, where depending on the cracking characteristics, the service life of the structures would be affected. In this paper, the effect of geometrical and material parameters, i.e., concrete cover thickness, reinforcing bar diameter, and concrete tensile strength, on the required pressure for concrete cover cracking due to corrosion has been investigated through detailed numerical simulations. ABAQUS finite element software is employed as a modeling platform where the concrete cracking is simulated by means of eXtended Finite Element Method (XFEM). The accuracy of the numerical simulations is verified by comparing the numerical results with experimental data obtained from the literature. Using a previously proposed empirical equation and the numerical model, the time from corrosion initiation to the cover cracking is predicted and then compared to the respective experimental data. Finally, a parametric study is undertaken to determine the optimum ratio of the rebar diameter to the reinforcing bars spacing in order to avoid concrete cover delamination.

• Journal of information and communication convergence engineering
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• v.6 no.2
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• pp.122-128
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• 2008

Multiprocessor architectures and platforms, such as, a multiprocessor system on chip (MPSoC) recently introduced to extend the applicability of the Moore's law, depend upon concurrency and synchronization in both software and hardware to enhance design productivity and system performance. With the rapidly approaching billion transistors era, some of the main problem in deep sub-micron technologies characterized by gate lengths in the range of 60-90 nm will arise from non scalable wire delays, errors in signal integrity and non-synchronized communication. These problems may be addressed by the use of Network on Chip (NOC) architecture for future System-on-Chip (SoC). We have modeled a concurrent architecture for a customizable and scalable NOC in a system level modeling environment using MLDesigner (from MLD Inc.). Varying network loads under various traffic scenarios were applied to obtain realistic performance metrics. We provide the simulation results for latency as a function of the buffer size. We have abstracted the area results for NOC components from its FPGA implementation. Modeled NOC architecture supports three different levels of quality-of-service (QoS).

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.737-742
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• 2009

As increasing emphasis is being placed on user experience design, the RIA technology is widely deployed for user interface and software operation on embedded devices including cell phones and TVs. In particular, RIA-based IPTV enables creation of various interactive contents via sophisticated animation and various input devices. This paper proposes a service framework for emotional contents on broadcast and communication-converged IPTV systems. We design a programming interface extension for IPTV-based flash contents and develop a prototype of flash runtime with the extended programming support. Since the proposed runtime was carefully designed to fully utilize the built-in graphic acceleration hardware in media processor, it supports high resolution graphic animation in resource-constrained IPTV environments.

• Journal of KIISE:Software and Applications
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• v.36 no.4
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• pp.283-290
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• 2009

Context-awareness is one of the key features of ubiquitous paradigm. A methodology that is specifying the relationships between the contexts and services needs to be developed to intelligently and sensitively deal with dynamic environment. The existing models on context-aware modeling are difficult to verify the correctness of models with respect to timeliness. In this paper we propose an approach which includes timing constraint in the relations of the context model, and verify its effectiveness using colored Petri-Net. Moreover, a context-modeling toolkit including context-awareness engine and simulator is developed to support agent-based context-aware service. The effectiveness of the proposed methodology is demonstrated using an example of Usilvercare.

• Journal of Korean Library and Information Science Society
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• v.40 no.2
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• pp.207-221
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• 2009

Reference services that use e-mail to receive reference questions and provide responses were developed as early digital reference services in the library field. However, librarians and users found that e-mail based reference services had some weak points when compared with traditional face-to-face reference services. As a result, libraries have started to create real-time reference services, which are similar to traditional face-to-face reference services through the use of synchronous chat software. Such chat reference services are focus of this paper. This paper approaches chat reference services as one of the services provided by libraries. Based on the understandings of the unique characteristics of services and the concept of "service quality", this paper tries to suggest appropriate marketing strategies of chat reference services.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.10
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• pp.75-80
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• 1999

Multimedia synchronization model for distributed, continuous or discrete media that was guaranteed high quality of service is requited in developing multimedia application software. In this paper we have specific object controller which is called dynamic key media that is changed by user event generation. This becomes media whose event occurrence and periods can't be predicted. For event occurrence not only audio but also text and image can be chosen for key media and performs its role. Object controller transfers information for next transition. The proposed model offers high qualify of services by permitting maximum allowed jitter and skew in playout time and verified its effectiveness by simulation.

• Convergence Security Journal
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• v.17 no.3
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• pp.3-9
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• 2017

NFV is a technology that allows network services to be controlled and managed in software by separating various net work functions (NFs) from hardware devices in dedicated network equipment and implementing them in a high-performance general-purpose server. Therefore, standardized virtualization of network functions is one of the most important factors. However, until the introduction of NFV to provide commercial services, there are many technical issues to be solved such as guaranteeing performance, stability, support for multi-vendor environment, ensuring perfect interoperability, and linking existing virtual and non-virtual resources. In this paper, we propose a method to provide an end-to-end network virtualization service based on OSM R2 in KREONET.

• Journal of Information Technology Applications and Management
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• v.20 no.1
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• pp.19-41
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• 2013

This study analyzed the users acceptance of e-Government services. Many IT(Information Technology) adoption studies appeared the TAM(technology adoption model) of Davis[1989] as a theoretical background. The TAM composed of three factors those are the perceived easy of use, the perceived usefulness, and intention to adoption of IT. However, TAM did not explain the consequences of intention to adoption and antecedents of the ease of use and usefulness in IT adoption. To overcome limitations of TAM, many technology acceptance studies done. In this study, the researcher suggested the IT acceptance model for explaining users adoption of e-Government service based on the model of IT acceptance of Wixom and Todd[2005]. The model of Wixom and Todd[2005] based on the TAM of Davis[1989], IT adoption model of Taylor and Todd[1995] and, IS(Information Systems) success model of Delone and Mclean[1992, 2003]. For testing our research model, the researcher collected data from 200 users of e-Government services. The researcher analyzed in measurement model and structural model using statistical software. This study analyzed relationships among interaction, information quality, Web systems quality, satisfaction, ease of use, usefulness, and attitude to explain and predict influences of the users acceptance of e-Government services. The results of this study will provide useful information about develop a strategy for usage spread of e-Government services.