• Journal of Communications and Networks
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• 제16권6호
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• pp.667-676
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• 2014

Connectivity is a crucial quality of service measure in wireless sensor networks. However, the network is always at risk of being split into several disconnected components owing to the sensor failures caused by various factors. To handle the connectivity problem, this paper introduces an in-advance mechanism to prevent network partitioning in the initial deployment phase. The approach is implemented in a distributed manner, and every node only needs to know local information of its 1-hop neighbors, which makes the approach scalable to large networks. The goal of the proposed mechanism is twofold. First, critical nodes are locally detected by the critical node detection (CND) algorithm based on the concept of maximal simplicial complex, and backups are arranged to tolerate their failures. Second, under a greedy rule, topological holes within the maximal simplicial complex as another potential risk to the network connectivity are patched step by step. Finally, we demonstrate the effectiveness of the proposed algorithm through simulation experiments.

• 디지털산업정보학회논문지
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• 제6권4호
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• pp.83-94
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• 2010

Mobile network infrastructure is being completed with the development of hardware and software for mobile devices. Network in mobile devices has evolved for telematics that is expanded much more than its existing concept. Telematics is compound word that is formed from the words "telecommunication" and "informatics". It means that telematics performs control and monitoring service with using mobile device resources. These services provide their services for users' requests through wired or wireless network from mobile devices and server that offers contents and network service collects management information of mobile devices. Map service is one of the preferred services for many telematics users. However, mobile map service has a limit between traffic and information sharing. Therefore it is very important to supply their information for both service provider and terminal user. In this paper, we design a new interactive sketch map using routes and information on the space to be applied effectively, and provide an extended document format that is defined to an extensible and dynamic clustering scheme to have portability map service for mobile device.

• Asia pacific journal of information systems
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• 제5권1호
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• pp.36-51
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• 1995

본 논문에서는 비구조적인 의사결정문제를 효과적으로 해결하기 위하여 감독학습 인공신경망 모형과 비감독학습 인공신경망 모형을 결합한 하이브리드 인공신경망 모형인 HYNEN(HYbrid NEural Network) 모형을 제안한다. HYNEN모형은 주어진 자료를 클러스터화 하는 CNN(Clustering Neural Network)과 최종적인 출력을 제공하는 ONN(Output Neural Network)의 2단계로 구성되어 있다. 먼저 CNN에서는 주어진 자료로부터 적정한 퍼지규칙을 찾기 위하여 클러스터를 구성한다. 그리고 이러한 클러스터를 지식베이스로하여 ONN에서 최종적인 의사결정을 한다. CNN에서는 SOFM(Self Organizing Feature Map)과 LVQ(Learning Vector Quantization)를 클러스터를 만든 후 역전파학습 인공신경망 모형으로 이를 학습한다. ONN에서는 역전파학습 인공신경망 모형을 이용하여 각 클러스터의 내용을 학습한다. 제안된 HYNEN 모형을 우리나라 기업의 도산자료에 적용하여 그 결과를 다변량 판별분석법(MDA:Multivariate Discriminant Analysis)과 ACLS(Analog Concept Learning System) 퍼지 ARTMAP 그리고 기존의 역전파학습 인공신경망에 의한 실험결과와 비교하였다.

• 한국통신학회논문지
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• 제12권3호
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• pp.254-266
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• 1987

분할법은 대규모회로망을 부분회로망으로 나누어서 해석하는 것으로 그 개념은 개회로와 폐회로에 대한 그래프 이론에 근거를 두고 있다. 본 논문에서는 대형회로망 고유값의 특성방정식을 분할법에 의하여 수식화 하고 반복법을 적용하여 간편하게 특성방정식의 해를 구함으로서 분할하지 않고 해석하는 방법에 비하여 효율적으로 처리할 수 있었다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2004년도 봄 학술발표논문집 Vol.31 No.1 (A)
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• pp.430-432
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• 2004

Multicasting is an efficient means of one to many (or many to many) communications. Due to the frequent and unpredictable topology changes, multicast still remains as challenge and no one-size-fits-all protocol could serve all kinds of needs in ad hoc network. Protocols and approaches currently proposed on this issue could be classified mainly into four categories, tree-based, meshed-based, statelessness and hybrid. In this article, we borrow the concept of Eulerian ring in graph theory and propose a novel ring-based multicast framework--Hierarchical Eulerian Ring-Oriented Multicast Architecture (HEROMA) over wireless mobile Ad hoc network. It is familiar with hybrid protocol based on mesh and tree who concentrates on efficiency and robustness simultaneously. Architecture and recovery algorithm of HEROMA are investigated in details. Simulation result is also presented, which show different level of improvements on end-to-end delay in scenario of small scale.

• 조명전기설비학회논문지
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• 제14권4호
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• pp.48-56
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• 2000

본 연구에서는 BAS에셔 사용이 확실시되는 Lonworks 네트워크의 새로운 개념과 설계방법을 제시하고 이를 이용하여 원격검침 및 조명 감시제어 실험시스템을 구축하고 실험을 통하어 개방적이고, 상호운용성을 가지는 제어 네트워크로서, 원격검침 및 감시시스템으로서도 매우 신뢰성 있고, 우수한 시스템임을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 D
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• pp.2410-2415
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• 2000

This paper propose the new concept & design method and implementation of LonWorks network system for telemetry & remote monitoring and control in BAS. In order to apply this open system, the essential components of LonWorks is analyzed and a new concepts of its design method is proposed. In our experiment, LonWorks network system for telemetry & remote monitoring and control of lighting are designed and fabricated. As a result, it is verified that LonWorks is open, interoperable, reliable network system from the experimental results, especially, node development, network configuration & design, secure communication and MMI.

• Genomics & Informatics
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• 제2권4호
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• pp.167-173
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• 2004

The main mechanism of evolution is that biological entities change, are selected, and reproduce. We propose a different concept in terms of the main agent or atom of evolution: in the biological world, not an individual object, but its interactive network is the fundamental unit of evolution. The interaction network is composed of interaction pairs of information objects that have order information. This indicates a paradigm shift from 3D biological objects to an abstract network of information entities as the primary agent of evolution. It forces us to change our views about how organisms evolve and therefore the methods we use to analyze evolution.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2005년도 하계학술대회
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• pp.318-322
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• 2005

An IP address plays both endpoint identifier and location identifier in wire based network. However, one IP address can not provide both endpoint identifier and location identifier for mobile Internet environment such as cellular network and portable Internet. To resolve this problem, mobile IPv4 and mobile IPv6 technologies are developed. These technologies are based on the concept of separation the endpoint identifier from location identifier. This paper describes some results of the recent studies such as mobile IPv4, mobile IPv6, host identify protocol and so on. Also, we propose the criteria to decide which technologies are suitable for deployment in the practical network environment.

• 한국정밀공학회지
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• 제21권7호
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• pp.15-21
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• 2004

A number of Humanoids are introduced including ASIMO, HRP-2 Promet, Johnniee, Babybot, and KHR-2. Most researches are focused on the development of stable biped walking of Humanoids and it is not easy to endow an Humanoid with intelligence and service technology until now in the sense that the operation time of a Humanoid is limited less than 30 minutes even in the case that the battery is used only for the control of actuators in a Humanoid. In this paper, a brief survey on Humanoids is proposed and the concept of 'Network-based Humanoid', a Humanoid being able to provide intelligence for human-friendly services using ubiquitous networks, is introduced briefly.