• Title/Summary/Keyword: Reliable Broadcast

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Reliability and Validity Assessment in 3D Video Measurement (3D 영상 평가를 위한 측정도구 신뢰도와 타당도 분석)

  • Chung, Dong-Hun;Yang, Ho-Cheol
    • Journal of Broadcast Engineering
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    • v.17 no.1
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    • pp.49-59
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    • 2012
  • Although 3D stereoscopic movies had been paid attention to a few times since the 1900's, the interest had not been last. Most researchers pointed out the reason came from human factors because the early in the 3D technology growth had to develop technological possibility to realize 3D videos and ignore the importance viewers' perspective. In the 2D video research, many studies have explored the factors which make people got immersed or involved and felt visual fatigue, but they have not been the main issues in the 3D research until now. The present research believes human factor issue is one of the most important parts to accelerate 3D industry and thus, we try to make reliable and valid assessments to evaluate 3D video which are perceived characteristics, impression, and presence.

Improvement of OLSR Through MIMC's Decreased Overhead in MANET (모바일 애드 혹 네트워크 환경 하에서 멀티인터페이스 멀티채널의 오버헤드 감소를 통한 OLSR의 성능 개선)

  • Jang, Jae-young;Kim, Jung-ho
    • KIPS Transactions on Computer and Communication Systems
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    • v.5 no.3
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    • pp.55-70
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    • 2016
  • The most critical research issue in MANET environment is on supporting reliable communication between various devices. Various Multi-Hop Routing Protocol studies have proceeded. However, some problems you might have found when you use the existing link state routing technique are that it increases Control Message Overhead and it is unstable when node moves in CR circumstance which has transformation of using channel and MIMC circumstance which uses a number of interfaces. This essay offers a technique which is based on On-Demand Hello and the other technique which used Broadcast Interface of optimization as a solution to decrease Control Message Overhead. Also it proposes Quick Route Restoration technique which is utilized by GPS and MPR Selection technique which consider mobility as a solution of stable communication when node moves. Those offered Routing Protocol and OPNET based simulator result will be expected to be an excellent comparison in related research fields.

Efficient Memory Update Module for Video Object Segmentation (동영상 물체 분할을 위한 효율적인 메모리 업데이트 모듈)

  • Jo, Junho;Cho, Nam Ik
    • Journal of Broadcast Engineering
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    • v.27 no.4
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    • pp.561-568
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    • 2022
  • Most deep learning-based video object segmentation methods perform the segmentation with past prediction information stored in external memory. In general, the more past information is stored in the memory, the better results can be obtained by accumulating evidence for various changes in the objects of interest. However, all information cannot be stored in the memory due to hardware limitations, resulting in performance degradation. In this paper, we propose a method of storing new information in the external memory without additional memory allocation. Specifically, after calculating the attention score between the existing memory and the information to be newly stored, new information is added to the corresponding memory according to each score. In this way, the method works robustly because the attention mechanism reflects the object changes well without using additional memory. In addition, the update rate is adaptively determined according to the accumulated number of matches in the memory so that the frequently updated samples store more information to maintain reliable information.

Covid-19 disaster text notificatioin service using location-based (위치기반을 이용한 코로나 재난 문자 알림 서비스)

  • Kim, Ga-eul;Moon, Seon-yun;Lee, Tae-heon;Park, Min-sook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2021.05a
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    • pp.395-396
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    • 2021
  • We have changed a lot in our lives because of a disease called Covid-19.One of the biggest changes is to check the "disaster notification character" service spent in the country every time it is sent in real time. By the way, we cannot accept the characters of other regional disasters other than the area where we live. After visiting other areas, when we returned to the area where we relocated, we experienced difficulty in confirming the flow lines because we could not receive the characters of the flow lines of the corona confirmed persons in the visited areas separately. And if you use the broadcast-type broadcast service, you will not receive unnecessary copper wire information, and you will be able to obtain the characters of the disaster only where we visited. We try to provide app services to provide the public with more accurate and reliable information.

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Power, mobility and wireless channel condition aware connected dominating set construction algorithm in the wireless ad-hoc networks (무선 에드 혹 네트워크에서 전력, 이동성 및 주변 무선 채널 상태를 고려한 연결형 Dominating Set 구성 방법)

  • Cho Hyoung-Sang;Yoo Sang-Jo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.5B
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    • pp.274-286
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    • 2005
  • In this paper, we propose a new power-efficient and reliable connected dominating set based routing protocol in the mobile ad hoc networks. Gateway nodes must be elected in consideration of residual energy and mobility because frequent reconstruction of connected dominating set result in transmission error for route losses. If node density is high, it results in a lot of contentions and more delays for network congestion. Therefore, in this paper, we propose a new construction method of connected dominating set that supports reliable and efficient data transmission through minimizing reconstruction of connected dominating set by delaying neighbor set advertisement message broadcast in proportion to weighted sum of residual energy, mobility, and the number of neighbor nodes. The performance of the proposed protocol is proved by simulation of various conditions.

Learning based relay selection for reliable content distribution in smart class application

  • Kim, Taehong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.8
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    • pp.2894-2909
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    • 2015
  • As the number of mobile devices such as smart phones and tablets explodes, the need for new services or applications is also rapidly increasing. Smart class application is one of the emerging applications, in which most of contents are distributed to all members of a class simultaneously. It is highly required to select relay nodes to cover shadow area of radio as well as extend coverage, but existing algorithms in a smart class environment suffer from high control packet overhead and delay for exchanging topology information among all pairs of nodes to select relay nodes. In addition, the relay selection procedure should be repeated in order to adapt to the dynamic topology changes caused by link status changes or device's movement. This paper proposes the learning based relay selection algorithm to overcome aforementioned problems. The key idea is that every node keeps track of its relay quality in a fully distributed manner, where RQI (Relay Quality Indicator) is newly defined to measure both the ability of receiving packets from content source and the ability of successfully relaying them to successors. The RQI of each node is updated whenever it receives or relays broadcast packet, and the node having the higher RQI is selected as a relay node in a distributed and run-time manner. Thus, the proposed algorithm not only removes the overhead for obtaining prior knowledge to select relay nodes, but also provides the adaptability to the dynamic topology changes. The network simulation and experimental results prove that the proposed algorithm provides efficient and reliable content distribution to all members in a smart class as well adaptability against network dynamics.

Capacity of Convergence System of Broadcasting and Communications in Correlated Nakagami Fading Channel (상관도를 갖는 Nakagami 페이딩 전송로에서의 방송통신융합시스템의 용량)

  • Kim, Joo-Chan;Kim, Yo-Cheol;Kim, Jin-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.9
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    • pp.3481-3485
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    • 2010
  • In this paper, we propose a concept and model of an additional service system as a kind of convergence system of broadcast and telecommunication. The proposed system use existing back-bone network such as broadcasting or communication networks. For this, we derive channel capacity formula as an approximated closed-form expression in order to show how many reliable additional data can be transmitted through wireless fading channel. From the derived formula, we confirm that the channel capacity is varied according to channel and system parameters.

An Efficient Directional MAC Protocol for Vehicular Ad-hoc Networks (차량 Ad-hoc에서 효율적인 메시지 전달을 위한 지향성 MAC 프로토콜)

  • Ji, Soonbae;Kim, Junghyun;You, Cheolwoo
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.4
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    • pp.9-16
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    • 2015
  • Quick and safe message transmission is an important research topic of vehicular ad hoc networks (VANET). Most studies assume that the periodic broadcast of beacon-frames between vehicles increases the safety of the driver. In this paper, we propose a medium access control (MAC) protocol and location-based clustering for the VANET to support reliable data transfer. In our proposal, the cluster heade (CH) manage the access and allocate the resources of the node. Our proposal uses simulation to confirm the reduction of the transmission delay and the collision rate of the signal.

An Implementation of the Position Controller for Multiple Motors Using CAN (CAN 통신을 이용한 다중모터 위치제어기 구현)

  • Yi, Keon-Young
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.51 no.2
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    • pp.55-60
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    • 2002
  • This paper presents a controller for the multiple DC motors using the CAN(Controller Area Network). The controller has a benefit of reducing the cable connections and making the controller boards compact through the network including expansibility. CAN, among the field buses, is a serial communication methodology which has the physical layer and the data link layer in the ISO's OSI (Open System Interconnect) 7 layered reference model. It provides the user with many powerful features including multi-master functionality and the ability to broadcast / multicast telegrams. When we use a microprocessor chip embedding the CAN function, the system becomes more economical and reliable to react shortly in the data transmission. The controller, we proposed, is composed of two main controllers and a sub controller, which have built with a one-chip microprocessor having CAN function. The sub controller is plugged into the Pentium PC to perform a CAN communication, and connected to the main controllers via the CAN. Main controllers are responsible for controlling two motors respectively. Totally four motors, actuators for the biped robot in our laboratory, are controlled in the experiment. We show that the four motors are controlled properly to actuate the biped robot through the network in real time.

Dynamic Reverse Route for On-Demand Routing Protocol in MANET

  • Zuhairi, Megat;Zafar, Haseeb;Harle, David
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.5
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    • pp.1354-1372
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    • 2012
  • Route establishment in Mobile Ad Hoc Network (MANET) is the key mechanism to a successful connection between a pair of source and destination nodes. An efficient routing protocol constructs routing path with minimal time, less routing overhead and capable of utilizing all possible link connectivity. In general, most on-demand MANET routing protocols operates over symmetrical and bidirectional routing path, which is infeasible due to the inherent heterogeneous properties of wireless devices. Simulation results show that the presence of unidirectional links on a network severely affect the performance of a routing protocol. In this paper, a robust protocol independent scheme is proposed, which enable immediate rediscovery of alternative route for a path blocked by a unidirectional link. The proposed scheme is efficient; route rediscovery is locally computed, which results in significant minimization of multiple route packets flooding. Nodes may exploit route information of immediate neighbors using the local reply broadcast technique, which then redirect the control packets around the unidirectional links, therefore maintaining the end-to-end bidirectional connection. The proposed scheme along with Ad Hoc On-demand Distance Vector (AODV) and AODV-Blacklist routing protocol is investigated over three types of mobility models. Simulation results show that the proposed scheme is extremely reliable under poor network conditions and the route connectivity can be improved by as much as 75%.