• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.12B
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• pp.1050-1057
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• 2008

Wireless Mesh Networks (WMNs) have recently become a hot issue to support high link capacity in wireless access networks. The IEEE 802. I 1 standard which is mainly used for the network interface technology in WMNs supports up to 3 or 12 multiple channels according to the IEEE 802.11 specification. However, two important problems must be addressed when we design a channel assigmnent algorithm: channel dependency problem and channel scanning delay. The former occurs when the dynamic channel switching of an interface leads to the channel switching of other interfaces to maintain node connectivity. The latter happens per channel switching of the interface, and affects the network performance. Therefore, in this paper, we propose the Distance-Based Channel Assigmnent (DB-CA) scheme for multi-channel WMNs to solve such problems. In DB-CA, nodes just perform channel switching without channel scanning to communicate with neighboring nodes that operate on different channels. Furthermore, DB-CA minimizes the interference of channels being used by nodes near the gateway in WMNs. Our simulation results show that DB-CA achieves improved performance in WMNs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.65-70
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• 2019

The purpose of this study is to understand the college students' needs for software curriculum which based on surveys from educational satisfaction of the software lecture evaluation, as well as to find out the improvement plan by applying the text content analysis method. The research method used the text content analysis program to calculate the frequency of words occurrence, key words selection, co-occurrence frequency of key words, and analyzed the text center and network analysis by using the network analysis program. As a result of this research, the decent points of the software education network are mentioned with 'lecturer' is the most frequently occurrence after then with 'kindness', 'student', 'explanation', 'coding'. The network analysis of the shortage points has been the most mention of 'lecture', 'wish to', 'student', 'lecturer', 'assignment', 'coding', 'difficult', and 'announcement' which are mentioned together. The comprehensive network analysis of both good and shortage points has compared among key words, we can figure out difference among the key words: for example, 'group activity or task', 'assignment', 'difficulty on level of lecture', and 'thinking about lecturer'. Also, from this difference, we can provide that the lack of proper role of individual staff at group activities, difficult and excessive tasks, awareness of the difficulty and necessity of software education, lack of instructor's teaching method and feedback. Therefore, it is necessary to examine not only how the grouping of software education (activities) and giving assignments (or tasks), but also how carried out group activities and tasks and monitored about the contents of lectures, teaching methods, the ratio of practice and design thinking.

• Archives of design research
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• v.16 no.4
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• pp.173-184
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• 2003

As homenetwork has been built at general homes, users want to connect various types of devices and control them. To realize a new environment that most people dream, there have been many services developed, and the various types of devices have been proposed and then their usage and validity have been reviewed. However, as the technical design guideline seems to be prepared soon for the standardization under the situation that has been progressed mainly by technology-lead style so far, making homenetwork a product is expected to be advanced, and therefore now it is the time to discuss the design development at full stage, which is really valuable for users. We have to consider it not to make any alienated class in the society on the whole when considering these devices, and also we have to develop the design by differentiating it toward the direction that we accept users and use environment's special conditions. In addition, each devices should have reliability, no malfunction or error and long life span. At the same time, those products, which can be new changes we can joyfully accept as well as the habits we are already accustomed to, should be developed, and thereby they may naturally have to be absorbed into our present living. The design development direction for future homenetwork can vary depending on our expectation and needs, and it will become a good guidebook for the producer who have to invest much financially or in time. Therefore, this study intends to examine the present network trend and development direction and then suggest the product design direction for future homenetwork.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.8
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• pp.796-804
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• 1992

This paper presents a design of a backbone network which uses a rigister-Insertion ring structure, The introduction of a high speed register in sertton backbone ring enables high performance inter-network 4ommunicatlons In a simple and modular structure at low cost and Its concurrent communications.. Two or more bridge nodes can be used to construct a register Insertion backbone ring network. The high bandwidth of the backbone ring sup ports heavy traffic for Inter-segment Eornrnunicatlons. The bridge node does both local address filtering to block data entering the ring and remote address filtering to block data entering the local LAN segment . Title local address greatly reduces the rate on the backbone ring and the remote address filterlng greatly reduces the traffic rate on each LAN segment. An feature makes the network the network reconflguratlon simpler and transparent to users. A throughput analysis Is used to deterrune the bandwidth of the backbone rlr)g transmission medium.

• JOURNAL OF ELECTRICAL WORLD
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• s.259
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• pp.70-77
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• 1998

미쓰비시전기는 제3세대 16비트 D램을 비롯한 0.4$\mu$m이하의 디자인룰을 갖는 ULSI를 대상으로, 직경 200mm웨이퍼 프로세스기술을 포함한 제조기술을 개발하여, 일본 국내, 대만, 독일에 양산공장을 전개하였다. 생산성이 우수한 디바이스/프로세스기술을 기반으로 저비용의 청정실 건설, 급수 등을 포함한 동력설비, 공장 자동화(FA), 컴퓨터제어식 제조공정(CIM), 북이단지구에있는 미쓰비시전기의 반도ㅔ개발거점과 각 공장간을 맺는 정보네트워크, 나아가 제조장치에 대한 철저한 저발진화와 결함관리를 위해 동사의 기술을 결집하여 생산성이 매우 높은 반도체양산공장을 글로벌하게 전개하였다. 우선 태본공장 최첨단 반도체라인(KD동)을 아주 짧은 기간에 가동시키는 소위 ''수직기동''을 실현하였다. 다음에 태본공장 KD동을 ''마더(Mother)공장''으로 하여 그대로 기술이전하는 ''Copy Exactly''라는 방법으로 이들 기술을 세계적으로 전개한 결과 대만에 있는 합병회사인 PS(Powerchip Semiconductor corporation)와 독일에 있는 생산회사 MSE(Mitsubishi Semiconducter Europe, GmbH)에서도 최첨단 반도체공장의 수직기동에 성공하였다. 이 공장은 0.25$\mu$m이후의 제품에도 대응가능하며 태본공장 KD동은 64M비트 D램으로 제품을 전환해가고 있다. 그렇게 하여 이들 공장과 개발거점을 네트워크호하여 다국적 기업에 걸맞는 세계적인 ULSI의 양산체제를 구축하였다.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10c
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• pp.179-181
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• 1999

본 논문에서는 내장 실시간 시스템(real-time embedded system)에서의 성능 재조정(re-engineering) 문제를 다룬다. 성능 재조정 문제는 하드웨어와 소프트웨어가 이미 구현된 상태에서 새로운 성능조건이 요구될 때 이를 만족시키도록 시스템을 수정하는 문제이다. 본 논문에서의 성능 요구조건은 시간당 처리량(throughput)이나 입출력 지연시간(input-output latency)등이 고려된다. 제안된 방법은 병목점 분석(bottleneck analysis)과 비선형 최적화를 이용한다. 이를 위해 프로세스 네트워크(process network)로 표현된 시스템 디자인과 태스크 그래프, 태스크 할당(allocation)과 스케쥴링, 그리고 새로운 성능조건인 실시간 처리량을 입력으로 사용한다. 제안된 방법은 두 단계로 구성된다. 첫째, 프로세스 네트워크에서 프로세스의 지연시간을 계산하여 병목이 되는 프로세스를 찾아낸다. 둘째, 프로세싱 요소의 성능 개선율(performance scaling factor)을 변수로 하여 주어진 성능을 만족시키기 위한 시스템 제약조건을 유도한다. 이를 사용하여 하드웨어의 업그레이드 비용을 최소화하도록 제약조건을 풀고 각 프로세싱 요소(processing element)에 필요한 성능개선율을 구한다. 제안된 방법은 기존에 구성된 소프트웨어의 구조를 고치기 않기 때문에 재조정의 시간을 줄일 수 있게 한다.

• Proceedings of the Korea Multimedia Society Conference
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• 2012.05a
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• pp.455-456
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• 2012

본 논문에서는 센서네트워크 연구단계에서 손쉽게 사용할 수 있는 센서데이터 모니터링 프로그램을 Java기반의 차트디자인 도구 JFreeChart를 이용하여 설계하고 구현한다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10c
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• pp.598-600
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• 2003

Ad­hoc 무선 망에서 directional antenna의 사용은 interference를 감소시키고 spatial reuse의 증가, 그리고 네트워크 전체의 capacity 증가 등의 장점을 제공한다. 하지만 기존의 IEEE 802.11 MAC protocol은 omnidirectional antenna를 고려하여 디자인되었기 때문에 기존의 MAC protocol이 directional antennas에 사용될 경우 directional antennas의 장점을 효율적으로 제공하지 못한다. Directional antenna는 이러한 장점을 가지는 반면에 RTS/CTS를 방향성 있는 전송을 하기 때문에 hidden terminal과 이웃 노드의 위치를 파악하는데 있어서 많은 문제를 가지고 있다. 이 논문에서 우리가 제안하는 MAC protocol은 directional antennas 특성상의 문제점을 해결하여 directional antennas의 장점을 최대한 이용한다.

• The Journal of Society for e-Business Studies
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• v.18 no.1
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• pp.191-211
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• 2013

The deployment of social network service(SNS) makes the social network game(SNG) as the new value added service of SNS be popular. But, a few study had identified the reason of this popularity and the elements of SNG. Based on the social presence theory and media richness theory, we had tried to identify three community artifacts (i.e. persistent labeling, self presentation and deep profiling) and two media characteristics(i.e. vividness and interactivity) as the SNG elements in this research. Then we had empirically validated the effect of these elements on the SNGexperience (i.e. social presence, perceived enjoyment) and behavioral intentions (i.e. Continuous usage intention, willingness to pay and loyalty) of the users. We conducted a survey to the actual SNG users. 243 data were collected and analyzed by PLS algorism. The results indicated that the community artifacts mediated by the social presence and media characteristics could significantly affect on the experiences and behavioral intentions. These findings could contribute to identify what element could be the reason of social network game popularity and could also contribute to design more attractive social network game in practice.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.40 no.6
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• pp.56-68
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• 2003

Difficult problems In implementing digital neural network hardware are the extension of synapses and the programmability for relocating neurons. In this paper, the structure of a new hardware is proposed for solving these problems. Our structure based on traditional SIMD can be dynamically and easily reconfigured connections of network without synthesizing and mapping original design for each use. Using additional modular processing unit the numbers of neurons find synapses increase. To show the extensibility of our structure, various models of neural networks : multi-layer perceptrons and Kohonen network are formed and tested. The performance comparison with software simulation shows its superiority in the aspects of performance and flexibility.