• 제목/요약/키워드: Real-time data communications

검색결과 515건 처리시간 0.022초

3D DISPLAY OF SPACECRAFT DYNAMICS USING REAL TELEMETRY

  • Lee, Sang-Uk;Cho, Sung-Ki;Kim, Jae-Hoon
    • Journal of Astronomy and Space Sciences
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    • 제19권4호
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    • pp.403-408
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    • 2002
  • 3D display of spacecraft motion by using telemetry data received from satellite in real-time is described. Telemetry data are converted to the appropriate form for 3-D display by the real-time preprocessor. Stored playback telemetry data also can be processed for the display. 3D display of spacecraft motion by using real telemetry data provides intuitive comprehension of spacecraft dynamics.

음성/데이터 CDMA 시스템에서의 서비스 품질을 고려한 비 실시간 데이터 패킷 전송 제어 정책 (QoS-Sensitive Admission Policy for Non-Real Time Data Packets in Voice/Data CDMA Systems)

  • Seungjae Bahng;Insoo Koo;Jeongrok Yang;Kim, Kiseon
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 추계종합학술대회 논문집
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    • pp.125-128
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    • 1999
  • In this paper, we propose a QoS-sensitive admission threshold method for the transmission of the non-real tine data packet such that the quality of services for both voice and data traffics are maintained to a required level. By detecting the active voice traffic during the current time slot, the non-real-time data packets are transmitted up to an admission threshold level during the next time slot. We found out that the optimum admission threshold is four voice traffic resources lower from the maximum allowable threshold to maintain the outage probability within 1% when the connected voice users are 15.

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Securing RTP Packets Using Per-Packet Key Exchange for Real-Time Multimedia

  • Jung, Younchan;Festijo, Enrique;Atwood, J. William
    • ETRI Journal
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    • 제35권4호
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    • pp.726-729
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    • 2013
  • For secure multimedia communications, existing encryption techniques use an online session key for the key exchange, for which key size is limited to less than 10 digits to accommodate the latency condition caused by user devices only being able to handle low computational loads. This condition results in poor security of recorded encrypted data. In this letter, we propose a packet key scheme that encrypts real-time packets using a different key per packet for multimedia applications. Therefore, a key of a relatively small size can provide after-transmission confidentiality to data of a real-time session.

Real-Time Animation of large Crowds

  • Kang, In-Gu;Han, Jung-Hyun
    • 한국HCI학회:학술대회논문집
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    • 한국HCI학회 2007년도 학술대회 3부
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    • pp.318-321
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    • 2007
  • This paper proposes a GPU-based approach to real-time skinning animation of large crowds, where each character is animated independently of the others. In the first pass of the proposed approach, skinning is done by a pixel shader and the transformed vertex data are written into the render target texture. With the transformed vertices, the second pass renders the large crowds. The proposed approach is attractive for real-time applications such as video games.

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Quick Evaluations of the KOMPSAT-1 Orbit Maneuvers Using Small Sets of Real-time GPS Navigation Solutions

  • Lee, Byoung-Sun;Lee, Jeong-Sook;Kim, Jae-Hoon
    • Transactions on Control, Automation and Systems Engineering
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    • 제3권3호
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    • pp.196-202
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    • 2001
  • Quick evaluations of two in-plane orbit maneuvers using small sets of real-time GPS navigation solutions were performed for the KOMPSAT-1 spacecraft operation. Real-time GPS navigation solutions of the KOMPSAT-1 were collected during the Korean Ground Station(KGS) pass. Only a few sets of position and velocity data after completion of the thruster firing were used for the quick maneuver evaluations. The results were used for antenna pointing data predictions for the next station contact. Normal orbit maneuver evaluations using large sets of playback GPS navigation solutions were also performed and the result were compared with the quick evaluation results.

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Quick Evaluation of Spacecraft Orbit Maneuver Using Small Sets of Real-time GPS Navigation Solutions

  • Lee, Byoung-Sun;Lee, Ho-Jin;Lee, Seong-Pal;Kim, Jong-Ah;Park, Hae-Jin
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.458-458
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    • 2000
  • Quick evaluations of two in-plane orbit maneuvers using small see of real-time CPS navigation solutions were peformed lot the KOMPSAT-1 spacecraft operation. Real-time GPS navigation solutions of the KOMPSAT-1 were collected during the Korean Ground Station(KGS) pass. Only a few sets of position and velocity data after completion of the thruster firing were used for the quick maneuver evaluations. The results were used for antenna pointing data predictions for the next station contact. Normal orbit maneuver evaluations using large see of playback GPS navigation solutions were also performed and the result were compared with the quick evaluation results.

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A Realtime Analytical System of Football Game

  • Min, Dae-kee
    • Communications for Statistical Applications and Methods
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    • 제8권2호
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    • pp.557-564
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    • 2001
  • The objective of he study is to record the real conditions along with the soccer ball that is, each player's ball keeping time, the number football keeping, accuracy of passing to other player, direction, etc., on a real-time basis, measure them in numbers and get necessary analyzed output as much as one needs. The study consists of the following stages: (1) Record the data by drawing through Visual Interface on a real-time basis; (2) Graphic windows to display the recorded data item by item in graphic; (3) Form windows to display the individual or team scores anytime when needed; (4) Windows to display the analyzed data in visualized form. The effect of the study is threefold: (1) It inputs all the game-related data on a real-time basis, which was impossible before and shows analyzed contents during the game enabling each tea manager o use; (2) In cse of TV broadcasting or newspaper articles, it explains objectively the situations of he game to the TV viewers or readers; (3) After the game, it provides importance information on each team's playing ability and individual player's technical improvement through data analysis.

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실시간제어시스템을 위한 데이터통신방식 (A Data Communication Method for Real-Time Control Systems)

  • 장태무
    • 한국통신학회논문지
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    • 제7권2호
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    • pp.66-70
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    • 1982
  • 多數의 마이크로프로세서와 이를 연결해 주는 미니컴퓨터로 構成된 實時間 온라인制御시스템에서의 데이터通信의 제반양식 및 그 접속단의 한 방안이 제시되고 설계되었다. 접속단은 DMA 方式으로 함으로써 방대한 制御프로그램을 단순화 할 수 있었다. 이 方式은 실제로 서울市의 交通管制시스템에서 活用되어 成功的으로 실험되었다.

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Data anomaly detection and Data fusion based on Incremental Principal Component Analysis in Fog Computing

  • Yu, Xue-Yong;Guo, Xin-Hui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권10호
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    • pp.3989-4006
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    • 2020
  • The intelligent agriculture monitoring is based on the perception and analysis of environmental data, which enables the monitoring of the production environment and the control of environmental regulation equipment. As the scale of the application continues to expand, a large amount of data will be generated from the perception layer and uploaded to the cloud service, which will bring challenges of insufficient bandwidth and processing capacity. A fog-based offline and real-time hybrid data analysis architecture was proposed in this paper, which combines offline and real-time analysis to enable real-time data processing on resource-constrained IoT devices. Furthermore, we propose a data process-ing algorithm based on the incremental principal component analysis, which can achieve data dimensionality reduction and update of principal components. We also introduce the concept of Squared Prediction Error (SPE) value and realize the abnormal detection of data through the combination of SPE value and data fusion algorithm. To ensure the accuracy and effectiveness of the algorithm, we design a regular-SPE hybrid model update strategy, which enables the principal component to be updated on demand when data anomalies are found. In addition, this strategy can significantly reduce resource consumption growth due to the data analysis architectures. Practical datasets-based simulations have confirmed that the proposed algorithm can perform data fusion and exception processing in real-time on resource-constrained devices; Our model update strategy can reduce the overall system resource consumption while ensuring the accuracy of the algorithm.

지적 아바타 통신을 위한 얼굴 표정의 실시간 생성에 관한 검토 (An Empirical Study on Real-time Generation of Facial Expressions in Avatar Communications)

  • 이용후;김상운;일본명
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅲ
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    • pp.1673-1676
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    • 2003
  • As a means of overcoming the linguistic barrier in the Internet cyberspace, recently a couple of studies on intelligent avatar communications between avatars of different languages such as Japanese-Korean have been performed. In this paper we measure the generation time of facial expressions on different avatar models in order to consider avatar models to be available in real-time system. We also provide a short overview about DTD (Document Type Definition) to deliver the facial and gesture animation parameters between avatars as an XML data.

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