• Title/Summary/Keyword: real-time network

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A Design of Integrated System for Real Time Multimedia Presentation and Content Creation (실시간 멀티미디어 프리젠테이션 및 컨텐트 제작을 위한 통합 시스템 설계)

  • 이규남;나인호
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.4 no.4
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    • pp.835-843
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    • 2000
  • This paper presents a method to design the integrated system for supporting both multimedia contents creation and its presentation in a windows system. Especially, it describes techniques for designing an integrated editor that can be used to crate and edit various media data including continuous media such as audio and video. And it also proposes a system model for systematically integrating multimedia creation tool with multimedia presentation system where the buffering and scenario-based presentation methods are included in the propose system for supporting effective multimedia presentation through a network. Finally, we describe a threads processing technique based on event monitoring to satisfy needs for presentation control, synchronization control, and user's input control during a multimedia presentation.

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Information Processing in Primate Retinal Ganglion

  • Je, Sung-Kwan;Cho, Jae-Hyun;Kim, Gwang-Baek
    • Journal of information and communication convergence engineering
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    • v.2 no.2
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    • pp.132-137
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    • 2004
  • Most of the current computer vision theories are based on hypotheses that are difficult to apply to the real world, and they simply imitate a coarse form of the human visual system. As a result, they have not been showing satisfying results. In the human visual system, there is a mechanism that processes information due to memory degradation with time and limited storage space. Starting from research on the human visual system, this study analyzes a mechanism that processes input information when information is transferred from the retina to ganglion cells. In this study, a model for the characteristics of ganglion cells in the retina is proposed after considering the structure of the retina and the efficiency of storage space. The MNIST database of handwritten letters is used as data for this research, and ART2 and SOM as recognizers. The results of this study show that the proposed recognition model is not much different from the general recognition model in terms of recognition rate, but the efficiency of storage space can be improved by constructing a mechanism that processes input information.

A Study on the Trend of an Avionics System Architecture Development for UAV (무인기 항공전자 체계의 아키텍처 개발 동향연구)

  • Kim, Sung Woo;Sim, Jae Ick;Lee, Wang Gug;Lee, Woo Jin;Won, Dae Yeon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.17 no.4
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    • pp.436-447
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    • 2014
  • The major elements of avionics system architecture are requirements, Real Time Operating System, message communication, memory, and data format etc. Herein describes a state-of-the-art development trend for the avionics system architecture, system requirements and data bus among the major elements of avionics system. While, domestic technology has been tried to Integrated Modular Avionics(IMA) system based on the Avionics Full Duplex Switched Ethernet(AFDX) technology during Light Attack Helicopter(LAH) project in Korea, but not yet proved as the product case in Full Scale Development Phase. The avionics system architecture considering the domestic inexperience of the IMA system architecture are suggested for the Next-generation Corps Unmanned Aircraft System.

A Study of Broadband Internet using Web Service Blind People of Distance Education Support Services (초고속통신망에서 인터넷 웹서비스를 이용한 시각장애인 원격교육지원 서비스연구)

  • Jung, Hoe-Jun;Park, Dea-Woo;Han, Kyung-Don
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2010.05a
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    • pp.385-388
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    • 2010
  • A place for the blind people movement restrictions in place on a relatively equal opportunity of education can not be provided. In this paper, blind people, as well as web access to information on the catch of the blind people and their preference for acquiring information on how to analyze the survey and analyze national and international stories. targeting the blind people Internet using Web Services in a high-speed network system design, training and support services, analyze and exchange information in real-time training program to develop a community, remote from the home education support system to revitalize blind people and would like to contribute to the information service.

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Real-time detection on FLUSH+RELOAD attack using Performance Counter Monitor (Performance Counter Monitor 를 이용한 FLUSH+RELOAD 공격 실시간 탐지 기술)

  • Cho, Jong-Hyeon;Kim, Tae-Hyun;Shin, Youngjoo
    • Annual Conference of KIPS
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    • 2018.10a
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    • pp.166-169
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    • 2018
  • 캐시 부채널 공격 중 하나인 FLUSH+RELOAD 공격은 높은 해상도와 적은 오류로 그 위험성이 높고, 여러가지 프로그램에서도 적용되어 개인정보의 유출에 대한 위험성까지 증명 되었다. 따라서 이 공격을 막기 위해 실시간으로 감지 할 수 있어야 할 필요성이 있다. 본 연구에서는 4가지 실험을 통하여 이 FLUSH+RELOAD 공격을 받을 때 PCM(Performance Counter Monitor)를 사용해 각각의 counter들의 값의 변화를 관찰하여 3가지 중요한 요인에 의해 공격 탐지를 할 수 있다는 것을 발견하였다. 이를 이용하여 머신 러닝의 logistic regression과 ANN(Artificial Neural Network)를 사용해 결과에 대한 각각 학습을 시킨 뒤, 실시간으로 공격에 대한 탐지를 할 수 있는 프로그램을 제작하였다. 일정한 시간동안 공격을 진행하여 모든 공격을 감지하는데 성공하였고, 상대적으로 적은 오탐률을 보여주었다.

Design of Encoding/Decoding Class Library for the MHEG-5 Objects (MHEG-5 객체의 인코딩/디코딩 클래스 라이브러리 설계)

  • Lee, Sei-Hoon;Wang, Chang-Jong
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.11
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    • pp.2671-2678
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    • 1997
  • The MHEG-5 standard defines representation of multimedia and hypermedia information. The MHEG-5 can make it possible to interchange and present information between heterogeneous networked environment. Also, it can provide real-time user interaction. MHEG-5 object generating is the essential requirements for the MHEG-5 applications, In this paper, we designed encoding/decoding class library for the MHEG-5 objects. We can use it for the interchange on the network. The designed class library can provide base technology for the MHEG-5 based distributed multimedia and hypermedia services on the networked environment.

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Transient State Improvement of Three-Phase ZSI with the Input Feedforward and Fuzzy PI Controller (입력 피드포워드와 퍼지 PI제어기를 갖는 3상 ZSI의 과도상태 개선)

  • WU, Yan-Jun;Jung, Young-Gook;Lim, Young-Cheol
    • Proceedings of the KIPE Conference
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    • 2012.07a
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    • pp.359-360
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    • 2012
  • This paper proposes a scheme of auto-tuning fuzzy PI controller and input voltage feed forward to control the output voltage of a three-phase Z-source inverter (ZSI). The proposed scheme adjusts the ts (Kp and Ki) in real time in order to find the most suitable Kp and Ki for PI controller and to simplify the controller design. The proposed scheme is verified the validity by experiment and co-simulation in PSIM and MATLAB/SIMULINK both load step change and input DC voltage variation in Z-source inverter, and has compared with the conventional PID control scheme. The experiment results involve of three-phase output voltage, Z-network capacitor voltage and dc-link peak voltage value. By those analysis and comparison, the availability of the proposed method in output voltage transient response quality improving has been verified. Compared with conventional PID method, the proposed method showed a more effective and robust control performance for coping with the severe disturbance conditions.

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Slotted ALOHA Based Greedy Relay Selection in Large-scale Wireless Networks

  • Ouyang, Fengchen;Ge, Jianhua;Gong, Fengkui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.10
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    • pp.3945-3964
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    • 2015
  • Since the decentralized structure and the blindness of a large-scale wireless network make it difficult to collect the real-time channel state or other information from random distributed relays, a fundamental question is whether it is feasible to perform the relay selection without this knowledge. In this paper, a Slotted ALOHA based Greedy Relay Selection (SAGRS) scheme is presented. The proposed scheme allows the relays satisfying the user's minimum transmission request to compete for selection by randomly accessing the channel through the slotted ALOHA protocol without the need for the information collection procedure. Moreover, a greedy selection mechanism is introduced with which a user can wait for an even better relay when a suitable one is successfully stored. The optimal access probability of a relay is determined through the utilization of the available relay region, a geographical region consisting of all the relays that satisfy the minimum transmission demand of the user. The average number of the selection slots and the failure probability of the scheme are analyzed in this paper. By simulations, the validation and the effectiveness of the SAGRS scheme are confirmed. With a balance between the selection slots and the instantaneous rate of the selected relay, the proposed scheme outperforms other random access selection schemes.

A Lifetime-Preserving and Delay-Constrained Data Gathering Tree for Unreliable Sensor Networks

  • Li, Yanjun;Shen, Yueyun;Chi, Kaikai
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.12
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    • pp.3219-3236
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    • 2012
  • A tree routing structure is often adopted for many-to-one data gathering and aggregation in sensor networks. For real-time scenarios, considering lossy wireless links, it is an important issue how to construct a maximum-lifetime data gathering tree with delay constraint. In this work, we study the problem of lifetime-preserving and delay-constrained tree construction in unreliable sensor networks. We prove that the problem is NP-complete. A greedy approximation algorithm is proposed. We use expected transmissions count (ETX) as the link quality indicator, as well as a measure of delay. Our algorithm starts from an arbitrary least ETX tree, and iteratively adjusts the hierarchy of the tree to reduce the load on bottleneck nodes by pruning and grafting its sub-tree. The complexity of the proposed algorithm is $O(N^4)$. Finally, extensive simulations are carried out to verify our approach. Simulation results show that our algorithm provides longer lifetime in various situations compared to existing data gathering schemes.

Design of Real-Time Operating System for Sensor Network based on $\mu$TMO Model ($\mu$TMO 모델 기반의 실시간 센서 네트워크 운영체제의 설계)

  • Lee, Jae-An;Choi, B.K.;Heu, Shin
    • Proceedings of the Korean Information Science Society Conference
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    • 2006.10a
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    • pp.167-171
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    • 2006
  • 무선 센서 네트워크는 유비쿼터스 컴퓨팅에서 생활 환경과 컴퓨터 사이의 중계자 역할을 하는 매우 중요한 연구 분야이다. 매우 제약적인 자원 환경에서 동작하여야 하는 센서 노드의 동작 환경적 특성 때문에 제한된 자원을 효율적으로 관리할 수 있는 센서 노드용 운영체제가 요구된다. 센서 노드는 제약적인 자원을 가지고 있지만 데이터 수집, 데이터 프로세싱, 다른 노드로부터 수신된 데이터의 전달 등 여러 가지 작업들이 동시에 발생된다. 기존의 범용 센서네트워크 운영체제에서는 극도로 제한된 자원을 최대한 효율적으로 사용할 수 있는 방법에 대하여 주로 연구해 왔다. 무선 센서 네트워크의 응용 범위가 점차 넓어지고 있다. 방사능 감지와 같이 실시간성을 요구하는 응용분야들이 생겨나기 시작하면서 센서 네트워크에서도 실시간성의 필요성이 대두되게 되었다. 실시간 센서 네트워크 연구 분야에서 실시간 통신 프로토콜의 연구 결과가 발표되고 있지만, 실시간 운영체제의 지원없이 완전한 실시간성을 보장하기 힘들다. 하지만 센서 노드용 실시간 운영체제에 대한 연구는 아직까지 활발히 진행되지 않고 있다. 본 논문에서는 정시성을 보장하는 분산 객체 모델인 TMO를 센서네트워크의 제한된 자원 환경에 알맞도록 경량화 시킨 $\mu$TMO 모델을 제시하고, 센서 노드용 운영체제에 $\mu$TMO 모델 을 적용하여 실시간성 지원에 따른 오버헤드를 감소시킨 실시간 센서 네트워크 운영체제의 구조를 제안한다.

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