• Title/Summary/Keyword: communication networks

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A Dynamic Channel Allocation Algorithm Based on Time Constraints in Cellular Mobile Networks

  • Lee, Seong-Hoon;Lee, Sang-Gu
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.3 no.1
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    • pp.18-22
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    • 2003
  • The new realtime applications like multimedia and realtime services in a wireless network will be dramatically increased. However, many realtime services of mobile hosts in a cell cannot be continued because of insufficiency of useful channels. Conventional channel assignment approaches didn't properly consider the problem to serve realtime applications in a cell. This paper proposes a new realtime channel assignment algorithm based on time constraint analysis of channel requests. The proposed algorithm dynamically borrows available channels from neighboring cells. It also supports a smooth handoff which continuously serves realtime applications of the mobile hosts.

Real-time Control on LonWorks/IP Virtual Device Network(VDN) for Rail Transit Vehicles (철도차량용 LonWorks/IP 가상 디바이스 네트워크 (VDN)에서의 실시간 분산제어)

  • Choi, Gi-Heung
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.1253-1258
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    • 2004
  • A general idea of implementing and managing real-time control on the VDN for rail transit vehicles is presented. In particular, the virtual device network considered in this paper is composed of Ethernet as the data network and LonWorks network as the device (control) network. A LonWorks/IP web server was used as a gateway to realize peer to peer data communication on the virtual device networks. Experimental results are given to validate the suggested architecture.

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Trend of 5G NR Based Open Small Cell Technologies (5G NR 기반 개방형 스몰셀 기술 동향)

  • Moon, J.M.;Bahg, Y.J.;Hwang, H.Y.;Na, J.H.
    • Electronics and Telecommunications Trends
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    • v.33 no.5
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    • pp.33-41
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    • 2018
  • The paradigm of mobile communication technology has changed from an increase in transmission capacity to service-based technologies satisfying various types of service requirements. One of the new paradigms is a service that provides users with a QoE (Quality Of Experience (QoE), at anytime and anywhere. 5G defines various technologies such as dense network structures and beam selection for increasing the transmission capacity and ensuring the quality of experience so as to satisfy this requirement, and related research is underway. In this paper, we describe the definition of a 5G small cell and 5G network structure as well as research trends of standardization and related technologies for constructing optimal solutions for mobile users in dense networks based on small cells.

Study for Improvement and Critical Issues Analysis in the Law for the Ubiquitous City Construction ("유비쿼터스 도시 건설 등에 관한 법률"의 주요 쟁점 분석 및 개선방안 연구)

  • Byun, Wan-Hee
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.8 no.3
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    • pp.112-121
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    • 2009
  • National government established a new law to solve the problems and to support u-City projects. Nevertheless there are still some issues which are a lack of the contents on national plan, connecting restriction among the communication networks between public institutions, a shortage of funds. This study investigated and analyzes these issues, and proposed some ideas to solve them.

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Research on Wireless Router for Data Relay between Binary CDMA Pico-Cell Networks (Binary CDMA Pico-Cell 네트워크간의 데이터 중계를 위한 무선 라우터에 대한 연구)

  • Park, Jong-Beom
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.10 no.4
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    • pp.116-124
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    • 2011
  • For Binary CDMA network, communication can be accomplished only within a Pico-net on the boundary of management by the master station because it manages network resources of each entity. In this research, we try to overcome these limits and extend the application for Binary CDMA system to broad-band network. We suggest a new Binary CDMA router such that network is devised by cell unit and multiple Pico-net and a unique address is assigned to each Pico-cell to relaying data between Pico-cells.

Implementation of Prototype using Wireless data modem for Gas valve remote locking system (무선 데이터 모뎀을 이용한 가스밸브 원격 차단장치 프로토 타입 구현)

  • Lee, Dong-Ju
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.917-920
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    • 2006
  • It is possible to make a practical application for many services by using Home Networking. It's brings much improve the quality of our life. Remote control communication should be made by Home Network but present networks are generally using wireless Internet. But, this method don't use exist home and not install wireless internet. Because It need to many devices. Therefore, in this paper we implement gas valve remote control system using RPM(Radio Packet Modem). We can easily installing systems and operating. This system provide different solution for Home networking.

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A Study On The Optimum Node Deployment In The Wireless Sensor Network System (무선센서 네트워크의 최적화 노드배치에 관한 연구)

  • Choi, Weon-Gab;Park, Hyung-Moo
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.99-100
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    • 2006
  • One of the fundamental problems in sensor networks is the deployment of sensor nodes. The Fuzzy C-Means(FCM) clustering algorithm is proposed to determine the optimum location and minimum number of sensor nodes for the specific application space. We performed a simulation using two dimensional L shape model. The actual length of the L shape model is about 100m each. We found the minimum number of 15 nodes are sufficient for the complete coverage of modeled area. We also found the optimum location of each nodes. The real deploy experiment using 15 sensor nodes shows the 95.7%. error free communication rate.

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Secure Transmission for Two-Way Vehicle-to-Vehicle Networks with an Untrusted Relay

  • Gao, Zhenzhen
    • IEIE Transactions on Smart Processing and Computing
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    • v.4 no.6
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    • pp.443-449
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    • 2015
  • This paper considers the physical layer security problem for a two-way vehicle-to-vehicle network, where the two source vehicles can only exchange information through an untrusted relay vehicle. The relay vehicle helps the two-way transmission but also acts as a potential eavesdropper. Each vehicle has a random velocity. By exploiting the random carrier frequency offsets (CFOs) caused by random motions, a secure double-differential two-way relay scheme is proposed. While achieving successful two-way transmission for the source vehicles, the proposed scheme guarantees a high decoding error floor at the untrusted relay vehicle. Average symbol error rate (SER) performance for the source vehicles and the untrusted relay vehicle is analyzed. Simulation results are provided to verify the proposed scheme.

An Efficient Data Transmission Scheme for Logistics Vehicles (물류 차량을 위한 효율적인 데이터 전송 방법)

  • Kim, Jong-Hyo;Yang, Jung-Min
    • IEMEK Journal of Embedded Systems and Applications
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    • v.13 no.2
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    • pp.93-100
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    • 2018
  • In this paper, we present a novel scheme of data transmission for logistics vehicles connected with 3G mobile communication networks. The proposed method enhances the efficiency of data transmission by varying the packet transmission period according to the vehicle speed and by reducing the amount of transmitted data using a reduced packet structure. The main contribution is to present the experimental verification in which the proposed method is applied to commercial logistics vehicles that operate with networked data transmission modules. Being compared with the existing method, the proposed scheme shows superior performance in terms of data reduction and transmission speed.

Optimized Identification of Genetic Algorithms based FPNN and Its Application to Nonlinear Data (진화 알고리즘 기반 FPNN의 최적 동정 및 비선형 데이터로의 응용)

  • Lee In-Tae;Lee Dong-Yoon;Kim Hyun-Ki;Oh Sung-Kwun
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2005.04a
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    • pp.305-308
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    • 2005
  • 본 논문은 유전자 알고리즘 기반 퍼지 다항식 뉴럴네트워크(Genetic Algorithm-based Fuzzy Polynomial Neural Networks ; GAs-based FPNN)를 이용하여 비선형 데이터의 최적화 추론 알고리즘을 제안한다. FPNN의 각 노드는 GMDH와 퍼지규칙을 기초로 만들었다. FPNN의 각 노드는 퍼지 다항식 뉴론(Fuzzy Polynomial Neuron : FPN)이라고 표현하다. 제안된 모델은 구조 선택에 있어서 유전자 알고리즘(Genetic Algorithms : GAs)을 이용하였다. 유전자 알고리즘을 사용하여 입력의 차수와 입력의 개수 그리고 후반부 추론의 형태를 최적 선택하였다. 비선형 데이터에 대한 모델 설계를 위해 최적화 알고리즘인 유전자 알고리즘 기반 FPNN 모델 설계가 유용하고 효과적임을 보인다.

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