• Journal of the Korea Convergence Society
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• v.11 no.11
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• pp.55-61
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• 2020

The communication issues expected for SMEs are that 1) IT systems are not easy to connect, 2) data collection and integration by heterogeneous systems are difficult, and 3) various fieldbuses and protocols make interfaces difficult. Usually, SMEs often have automation built before the introduction of smart factories. It is necessary to provide communication technology such as Sensing to meet the heterogeneous system level with the old aged sensors in the automation equipment and communication network of SMEs. We will consider how to improve the network interface before applying the latest network technology at the time of preparation using PI.

• Journal of Communications and Networks
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• v.7 no.4
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• pp.525-536
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• 2005

In an IP-based network, automated dynamic assignment of IP addresses is preferable. In most wired networks, a node relies on a centralized server by using dynamic host configuration protocol (DHCP) to obtain a dynamic IP address. However, the DHCP­based approach cannot be employed in a mobile ad hoc network (MANET) due to the uncertainty of any centralized DHCP server. That is, a MANET may become partitioned due to host mobility. Therefore, there is no guarantee to access a DHCP server. A general approach to address this issue is to allow a mobile host to pick a tentative address randomly, and then use duplicate address resolution (DAR) protocol to resolve any duplicate addresses. In this paper, an innovative distributed dynamic host configuration protocol designed to configure nodes in MANET is presented. The proposed protocol not only can detect the duplicate address, but also can resolve the problem caused by duplicate address. It shows that the proposed protocol works correctly and is more universal than earlier approaches. An enhanced version of DAR scheme is also proposed in this paper to solve the situation of duplicate MAC address. The new and innovative approach proposed in this paper can make the nodes in MANET provide services to other networks and avoid packets from being delivered to incorrect destinations.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.10
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• pp.901-906
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• 2013

Chaff is a kind of matter spreading atmosphere with the purpose of preventing aircraft from detecting by radar. The chaff is commonly composed of small aluminum pieces, metallized glass fiber, or other lightweight strips which consists of reflecting materials. The chaff usually appears on the radar images as narrow bands shape of highly reflective echoes. And the chaff echo has similar characteristics to precipitation echo, and it interrupts weather forecasting process and makes forecasting accuracy low. In this paper, the chaff echo recognizing and removing method is suggested using Bayesian network. After converting coordinates from spherical to Cartesian in UF (Universal Format) radar data file, the characteristics of echoes are extracted by spatial and temporal clustering. And using the data, as a result of spatial and temporal clustering, a classification process for analyzing is performed. Finally, the inference system using Bayesian network is applied. As a result of experiments with actual radar data in real chaff echo appearing case, it is confirmed that Bayesian network can distinguish between chaff echo and non-chaff echo.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.1
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• pp.35-57
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• 2014

Multi-criteria decision making (MCDM) algorithms play an important role in ensuring quality of service in an integrated HetNets (Heterogeneous Networks). The primary objective of this paper is to develop a multi-criteria vertical handoff decision algorithm (VHDA) for best access network selection in an integrated Wireless Local Area Network (WLAN)/Universal Mobile Telecommunications System (UMTS)/Worldwide Interoperability for Microwave Access (WiMAX) system. The proposed design consists of two parts, the first part is the evaluation of an Analytic Hierarchy Process (AHP) to decide the relative weights of handoff decision criteria and the second part computes the final score of the weights to rank network alternatives using Simple Additive Weighting (SAW). SAW ranks the network alternatives in a faster and simpler manner than AHP. The AHP-SAW mathematical model has been designed, evaluated and simulated for streaming video type of traffic. For other traffic type, such as conversational, background and interactive, only simulation results have been discussed and presented in brief. Simulation results reveal that the hierarchical modelling and computing provides optimum solution for access network selection in an integrated environment as obtained results prove to be an acceptable solution to what could be expected in real life scenarios.

• The KIPS Transactions:PartA
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• v.17A no.5
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• pp.237-248
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• 2010

UPnP(Universal Plug and Play) is a middleware of DLNA (Digital Living Network Alliance) services a home network. UPnP supports the connections between each other devices in networks and also provides service discovery and advertisement with SSDP(Simple Service Discovery Protocol), which is generally designed for wired networks. SSDP operates on multicasting discovery request and advertisement and unicasting a reply in networks. It is a challenge issue for service discovery protocol such as SSDP to provide a stable and effective service in wireless ad-hoc networks. Wired based service discovery protocol does not consider the dynamics of wireless ad-hoc network. In that case, the nodes are freely in or out. Therefore, this paper proposes a flexible SSDP(fSSDP) which is a peer-to-peer(P2P) discovery protocol adopted for wireless ad-hoc Networks. It is implemented on the extension of SSDP. fSSDP supports a functionality that the broadcast area of service discovery dynamically changes with the periodically updated area of advertisement. It is good for reducing messaging overhead caused from the broadcast flooding of service discovery in wireless ad-hoc network.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.420-420
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• 2006

• Information and Communications Magazine
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• v.19 no.7
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• pp.72-77
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• 2002

This paper introduces the Future Technologies for Universal Radio Environment (FUTURE), which is China's wireless communications research project oriented to beyond 3G systems. The features and basic requirements of the FUTURE project are described, and the system structure, which is based on IPv6 core network, is proposed. The key techniques for FUTURE project are also addressed.

• Communications for Statistical Applications and Methods
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• v.14 no.3
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• pp.601-608
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• 2007

Lee, et al. (1999) proposed a unique but universal robust objective function replacing the square objective function for the radial basis function network, and demonstrated some advantages. In this article, the robust objective function in Lee, et al. (1999) is adapted for a multilayer perceptron (MLP). The shape of the robust objective function is formed by the scale parameter. Another method of determining a proper value of that parameter is proposed.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10c
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• pp.625-627
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• 2004

최근 홈 네트워크 상에서 가전기기를 통합 제어하는 무선 통합 컨트롤러의 연구 개발이 활발히 진행되고 있다. 본 논문에서는 근거리 무선망인 블루투스를 사용하며 가정 내에서 가전기기를 제어하는 블루투스 통합 컨트롤러를 설계하고 구현한다. 제안된 통합 컨트롤러는 사용자 관리 및 기기의 세부기능 제어를 위해 메신저 형식의 사용자 인터페이스로 설계한다 또한 블루투스의 SOP(Service Discovery Protocol)를 사용하여 댁내 가전기기를 위한 서비스를 동적 발견하고 관리한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.7
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• pp.1001-1005
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• 2002

In march 2002, Study Group on Long-Run Incremental Cost(LRIC) Model of Japan compiled its report. In this report shows there are three ways of inter-islands and island to land telecommunication service, radio communication, suboptic, communication satellite. Analysis of Japanese island network model is helpful in developing Korean island network model. The development of Korean island network model will make he useful costing of local loop unbundling, universal service fund and access charge.