• Title/Summary/Keyword: communication networks

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A Study of Stable Route Decision Based on VANET Routing Protocol in Urban Environment (도심환경에서의 안정적 경로 설정을 위한 VANET 라우팅 프로토콜)

  • Ham, Woo-Hyung;Jang, Sang-Woo;Lee, Sang-Sun
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.11 no.3
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    • pp.70-80
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    • 2012
  • In Vehicular Ad-hoc Network(VANET) which constructs networks without fixed infrastructure among vehicles, network topology is frequently changed due to high mobility. In case of urban model, communication disconnections caused by interruptions of communication propagation such as buildings and constructions could be often occurred. Therefore, in VANET environment a routing protocol to complement its characteristics is needed. This paper suggests an algorithm to improve the transmission performance at intersections by approaching of the distance-based broadcasting which utilizes the information of vehicle's position. By using relative velocity among vehicles, it makes the stability of route decision improved and reduces packet collisions through graded priorities in the intersection, and simultaneously improves the performance of data rate. It can be seen that the performance compared with previous algorithm is significantly improved when using the suggested algorithm in the urban traffic environment.

A Design and Implementation for Registration Service of IoT Embedded Node using CoAP Protocol-based Resource Directory in Mobile Internet Environments (모바일 인터넷 환경에서 CoAP 프로토콜 기반의 RD를 이용한 IoT 임베디드 노드 등록 서비스 설계 및 구현)

  • Hang, Lei;Jin, Wenquan;Kim, Do-Hyeun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.1
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    • pp.147-153
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    • 2016
  • Recently, IETF (Internet Engineering Task) working group has adopted CoAP (Constrained Application Protocol) as a standard IoT proctocol. CoAP is a specialized web transfer protocol for use with constrained nodes and constrained environment such as small memory and low power networks. In this paper, we design and implement a registration service with CoAP protocol based on RD(Resource Directory) to connect IoT nodes in mobile Internet environments. The resource directory between the mobile terminal and IoT nodes provides to discover the IoT nodes and get the context data. The mobile terminal has as the CoAP client and embedded IoT nodes includes as the CoAP server so that it can conveniently manage the constrained IoT nodes to get the context data and control devices in a mobile environments.

Performance Analysis of TCP Variants using AQM and ECN (AQM과 ECN을 사용한 TCP 변종의 성능 분석)

  • Matten, Ahmad;Anwar, Adnan
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.1
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    • pp.129-137
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    • 2016
  • Transmission Control Protocol as a transport layer protocol provides steady data transfer service. There are some serious concerns about the performance of TCP over diverse networks. The vital concern in TCP network environment is congestion which may occur due to quick transmission rates or because of large number of new connections entering the network at the same time. Size of queues in routers grows thus resulting in packet drops. Retransmission of the dropped packets, and reduced throughput can prove costly. Explicit Congestion Notification (ECN) in conjunction with Active Queue Management mechanisms (AQM) such as Random early detection (RED) is used for packet marking rather than dropping. In IP packet header ECN bits can be added as a sign of congestion thus avoiding needless packet drops. The proposed ECN and AQM mechanism can be implemented with help of ns2 simulator and the performance can be tested on different TCP variants.

Smart LED Push Notification System based on Android (안드로이드 기반 스마트 LED 푸시 알람 시스템)

  • Hyeong, Jae-Ho;Jeon, Ho-Seok;Shin, Chang-Hoon;Chang, Min-Ho;An, Beongku
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.1
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    • pp.97-102
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    • 2016
  • In this paper, we propose an Android-based smart LED push notification system. The main feature and contribution of the proposed system are as follows. First, because it notifies messages using LED lights, it is possible to check anywhere in the house without carrying the smartphone. Second, the external control using Web2py can not only manages simple LED control but one can also add notification system indicating various conditions inside the house such as motion recognition sensor, temperature sensor. Performance evaluation of the proposed system is executed by two kinds of view point as: First, how to response instantly according to the incoming signal of LED control and notification in the given networks. Second, how to recognize the change of LED light. The results of experiment show that the efficiency and convenience of the proposed system is verified from the user's point of view.

Design and Development of Simulation Framework for Processing Window Query in Wireless Spatial Data Broadcasting Environment (무선 공간 데이터 방송 환경에서 범위 질의 처리를 위한 시뮬레이션 프레임워크의 설계와 구현)

  • Im, Seokjin;Hwang, Hee-Joung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.5
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    • pp.173-178
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    • 2014
  • Smart devices linked to high speed networks enable us to obtain location dependent data at anywhere and anytime. In this environment, a wireless data broadcast system can deal with enormous data request from a great number of clients effectively. In order to set up an efficient wireless data broadcast system, various data scheduling and indexing schemes have been proposed. However, a simulation framework to evaluate the schemes is not reported yet. In this paper, we design and develop a simulation framework for a wireless data broadcast system. The developed simulation framework can evaluate quickly a wireless data broadcast system and has scalability to adopt various data scheduling and indexing schemes for wireless data broadcasting.

A Study of Visualization Scheme of Sensing Data Based Location on Maps (지도에서 위치 기반의 센싱 데이터 가시화 방안 연구)

  • Choi, Ik-Jun;Kim, Yong-Woo;Lee, Chang-Young;Kim, Do-Hyeun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.8 no.5
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    • pp.57-63
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    • 2008
  • Recently, OGC(Open Geospatial Consortium) take the lead in SWE(Sensor Web Enablement) research that collection various context information from sensor networks and show it on map by web. OGC SWE WG(Working Group) defines a standard encoding about realtime spatiotemporal appear geographical feature, sensing data and support web services. This paper proposes a visualization scheme of sensing data based location on 2D maps. We show realtime sensing data on moving node that mapping GPS data on map. First, we present an algorithm and procedure that location information change to position of maps for visualization sensing data based on 2D maps. For verifying that algorithm and scheme, we design and implement a program that collecting GPS data and sensing data, and displaying application on 2D maps. Therefore we confirm effective visualization on maps based on web which realtime image and sensing data collected from sensor network.

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Design of the Smart Application based on IoT (사물 인터넷 기반 스마트 응용의 설계)

  • Oh, Sun-Jin
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.5
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    • pp.151-155
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    • 2017
  • With the rapid growth of the up-to-date wireless network and Internet technologies, huge and various types of things around us are connected to the Internet and build the hyper-connected society, and lots of smart applications using these technologies are actively developed recently. IoT connects human, things, space, and data with various types of networks to construct the hyper-connected network that can create, collect, share and appling realtime information. Furthermore, most of the smart applications are concentrated on the service that can collect and store realtime contexts using various sensors and cloud technology, and provide intelligence by making inferences and decisions from them nowadays. In this paper, we design a smart application that can accurately control and process the current state of the specific context in realtime by using the state-of-the-art ICT techniques such as various sensors and cloud technologies on the IoT based mobile computing environment.

DeepPurple : Chess Engine using Deep Learning (딥퍼플 : 딥러닝을 이용한 체스 엔진)

  • Yun, Sung-Hwan;Kim, Young-Ung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.5
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    • pp.119-124
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    • 2017
  • In 1997, IBM's DeepBlue won the world chess championship, Garry Kasparov, and recently, Google's AlphaGo won all three games against Ke Jie, who was ranked 1st among all human Baduk players worldwide, interest in deep running has increased rapidly. DeepPurple, proposed in this paper, is a AI chess engine based on deep learning. DeepPurple Chess Engine consists largely of Monte Carlo Tree Search and policy network and value network, which are implemented by convolution neural networks. Through the policy network, the next move is predicted and the given situation is calculated through the value network. To select the most beneficial next move Monte Carlo Tree Search is used. The results show that the accuracy and the loss function cost of the policy network is 43% and 1.9. In the case of the value network, the accuracy is 50% and the loss function cost is 1, respectively.

Design and Implementation of Personal Information Identification and Masking System Based on Image Recognition (이미지 인식 기반 향상된 개인정보 식별 및 마스킹 시스템 설계 및 구현)

  • Park, Seok-Cheon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.5
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    • pp.1-8
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    • 2017
  • Recently, with the development of ICT technology such as cloud and mobile, image utilization through social networks is increasing rapidly. These images contain personal information, and personal information leakage accidents may occur. As a result, studies are underway to recognize and mask personal information in images. However, optical character recognition, which recognizes personal information in images, varies greatly depending on brightness, contrast, and distortion, and Korean recognition is insufficient. Therefore, in this paper, we design and implement a personal information identification and masking system based on image recognition through deep learning application using CNN algorithm based on optical character recognition method. Also, the proposed system and optical character recognition compares and evaluates the recognition rate of personal information on the same image and measures the face recognition rate of the proposed system. Test results show that the recognition rate of personal information in the proposed system is 32.7% higher than that of optical character recognition and the face recognition rate is 86.6%.

The forming, practicing and shifting of the discourse on the convergence of broadcasting & telecommunication (방송통신융합 담론의 형성과 실천 그리고 변위)

  • Lee, Won
    • Korean journal of communication and information
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    • v.48
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    • pp.25-45
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    • 2009
  • The convergence of broadcasting & telecommunication is not a reality by itself, but recognized as a reality by the discourse which defines and explains it. It is the premise from which this article aims at studying how the discourse on the broadcasting-telecommunication convergence is formed, practised and transformed. This study compares the case of France with the case of Korea in order to show how the same discourse can engender different consequences and evolve in a different way in different socio-political situations. The discourse of the convergence was born as a scientific knowledge in the reports of the European Commission and OECD, and accepted as an important object generating social debates. Then, the discourse faces the resistance of pre-existent discourses in France, while it spreads without clash in South Korea. The French discourse results in a horizontal regulation of contents and networks, while the Korean discourse creates a unique regulator for both traditionally distinguished sectors. Finally, unlike France, the scientific discourse of the convergence in South Korea is transformed into even a political, imaginary or utopian discourse.

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