• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.12
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• pp.38-45
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• 2003

Recently, localized QoS routing scheme was recently proposed for overcome drawbacks of global state QoS routing schemes. Localized QoS routing dose not exchange QoS states among routers, but use virtual capacity based routing scheme instead. In localized QoS routing, to archive good performance, a set of candidate paths must be selected between the source and the destination effectively. In this paper we propose a few heuristics for effective path selection and develop path selection algorithms based on the heuristics. More detail analysis of the proposed algorithm is presented with simulation results which demonstrate that the path selection method can very affect the performance of localized QoS routing.

• Proceedings of the Korea Information Processing Society Conference
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• 2021.11a
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• pp.449-452
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• 2021

산업제어시스템은 IT 기술의 발전에 따라 다양한 기기 환경과 네트워크를 적용해 진화하고 있다. 이러한 상황에서 사이버 보안의 위협은 가중되고 있으며, 이를 예방하는 방법의 하나로 산업제어시스템에 탑재되는 소프트웨어의 소스코드 개발 과정에서 보안 취약점을 예방하기 위해 소스코드 보안 룰을 적용하여 위반사항을 제거한다. 본 연구에서는 소스코드 보안 룰에서 적용 우선순위를 선정하기 위한 가이드를 개발한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.1314-1315
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• 2008

Recent research work has unearthed that multi-radio multi-channel wireless mesh networks offer considerable capacity gains over single-radio wireless mesh networks. In this paper, we present a new routing metric for multi-radio multi-channel wireless mesh networks. The goal of the metric is to choose multiple link/node disjoint paths between a source and destination node that, when used concomitantly, impart high end-to-end throughput. The proposed metric selects high fidelity paths that will produce elevated throughput with maximum fault tolerance.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.11
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• pp.5343-5364
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• 2016

Considering the tradeoff between energy consumption and outage behavior in buffer-aided relay selection, a novel energy-efficient buffer-aided optimal relay selection scheme with power adaptation and Inter-Relay Interference (IRI) cancellation is proposed. In the proposed scheme, energy consumption minimization is the objective with the consideration of relay buffer state, outage probability and relay power control, in order to eliminate IRI. The proposed scheme selects a pair of optimal relays from multiple candidate relays, denoted as optimal receive relay and optimal transmit relay respectively. Source-relay and relay-destination communications can be performed within a time-slot, which performs as Full-Duplex (FD) relaying. Markov chain model is applied to analyze the evolution of relay buffer states. System steady state outage probability and achievable diversity order are derived respectively. In addition, packet transmission delay and power reduction performance are investigated with a specific analysis. Numerical results show that the proposed scheme outperforms other relay selection schemes in terms of outage behavior with power adaptation and IRI cancellation in the same relay number and buffer size scenario. Compared with Buffer State relay selection method, the proposed scheme reduces transmission delay significantly with the same amount of relays. Average transmit power reduction can be implemented to relays with the increasing of relay number and buffer size, which realizes the tradeoff between energy-efficiency, outage behavior and delay performance in green cooperative communications.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.1A
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• pp.36-43
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• 2008

In this paper, we propose an optimal relay selection scheme for decode-and-forward relaying systems. The optimal relay selection minimizes the number of time slots used to relay source's signal and maximizes an end-to-end signal-to-noise ratio. However, decode-and-forward relaying systems require additional overhead for the optimal relay selection. Assuming independent and identically distributed Rayleigh fading channels, we provide exact and closed-form expressions for the outage probability of capacity and the bit error rate for decode-and-forward relaying systems with the optimal relay selection. It is shown that the analytic results are perfectly matched with the simulated ones. When the numbers of relay nodes are 2, 4, and 8, and the numbers of time slots for overhead are 1, 2, and 4, respectively, the proposed system achieves 1 dB, 2 dB, and 3 dB gains at 1% bit error rate, respectively, and 0.5 dB, 4 dB, and 12 dB gains at 1% outage probability for 1 bps/Hz, respectively, over the conventional decode-and-forward relaying system.

• The Research Journal of the Costume Culture
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• v.17 no.1
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• pp.162-176
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• 2009

This study is to compare clothing purchasing behaviors between Korean and American college students, especially men. A theoretical study was reviewed, then the survey was performed. 200 questionnaires were utilized for this study. The SPSS 12.0 was used to analyze the technical statistics like average, frequency, t-test, $X^2$, and factor analysis. The result showed, first there were some differences in most of all the clothing Purchasing behaviors such as the reason for the purchases, the purchasing information source, the standard of selecting clothes and the standards of selecting stores. There were slight differences in the reasons for the purchases between Korean and American college men. Both of them said that they purchase clothes to satisfy their needs and the situation. The American college men were slightly higher than the Korean college men for both the need.situation and impulse motive. Regarding the information sources for the purchase, The Korean college men were slightly higher than the American college men for the media information sources and lower than them for the human information sources. Regarding the standard for store selection, the college men from both countries considered product service to be the most important. The American college men considered the convenient and store services to be more important than Korean college men. Regarding the standard fur clothes selection, the Korean college men considered the clothing that matched their personal styles to be the most important standard, however, the American college men considered the attractive from the opposite sex as the important standard.

• International Journal of Computer Science & Network Security
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• v.22 no.3
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• pp.285-291
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• 2022

WSN is the major component for information transfer in IoT environments. Source Location Privacy (SLP) has attracted attention in WSN environments. Effective SLP can avoid adversaries to backtrack and capture source nodes. This work presents a Two-Level Randomized Sector-based Routing (TLRSR) model to ensure SLP in wireless environments. Sector creation is the initial process, where the nodes in the network are grouped into defined sectors. The first level routing process identifies sector-based route to the destination node, which is performed by Ant Colony Optimization (ACO). The second level performs route extraction, which identifies the actual nodes for transmission. The route extraction is randomized and is performed using Simulated Annealing. This process is distributed between the nodes, hence ensures even charge depletion across the network. Randomized node selection process ensures SLP and also avoids depletion of certain specific nodes, resulting in increased network lifetime. Experiments and comparisons indicate faster route detection and optimal paths by the TLRSR model.

• The Research Journal of the Costume Culture
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• v.20 no.6
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• pp.838-853
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• 2012

The purpose of this study is to identify adult learners' decision making variables, satisfaction, and evaluation toward fashion education as a university lifelong education program. As decision making variables, this study included participation purpose, information source, and selection criteria for lifelong education center and program. Regarding satisfaction toward fashion education, this study included satisfaction toward program and satisfaction toward education condition and administrative services. Data were gathered by both questionnaires and focus group interview(FGI) with 12 adults who completed the program. While questionnaires were used for decision making variables and satisfaction, FGI was used for evaluation. Frequency was used to analyze the questionnaires and content analysis was used to analyze the results of FGI. The findings showed that respondents participated mostly because of hobby or interest and got information mostly from acquaintances. They regarded program contents as the selection criteria for lifelong education center. They also regarded lecturers' professionality as the selection criteria for the program and showed high satisfaction toward lecturers' passion. Regarding education condition and administrative services, they showed high satisfaction. FGI also showed the importance of individual competence, career development, a work-study program, a on-site study program, and lecturer. The results suggest methods to make university lifelong education programs more appealing to adults who want to attend universities for non-degree university programs.

• KIPS Transactions on Computer and Communication Systems
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• v.2 no.11
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• pp.471-474
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• 2013

In this paper, we propose a distributed parent peer selection method to construct an efficient peer-to-peer(P2P) network topology by considering the capacity of a peer and the hop distance from a data source to the peer. To achieve this goal, we propose a method to combine the two performance metrics to calculate the probability that a peer becomes a parent peer. Using the probability, we propose a method to select a parent peer stochastically by making use of the state information of the neighboring peers that each peer maintains. Through simulation studies, we show that the proposed method drives high capacity peers to support more children peers and makes the diameter of the P2P network shorter than the other methods.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.4
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• pp.49-55
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• 2004

This paper describes a 1550 nm multichannel source using Quatemary/quatemary multiple quantum well (MQW) InGaAsP/InGaAsP quantum confined Stark effect (QCSE) tuning for dense wavelength division multiplex (DWDM) systems with 140 ㎓ channel spacing and 32 nm channel selection bandwidth.