• Title/Summary/Keyword: Data sensing-control

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SPACE-BASED OCEAN SURVEILLANCE AND SUPPORT CAPABILITY

  • Yang Chan-Su
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.253-256
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    • 2005
  • The use of satellite remote sensing in maritime safety and security can aid in the detection of illegal fishing activities and provide more efficient use of limited aircraft or patrol craft resources. In the area of vessel traffic monitoring for commercial vessels, Vessel Traffic Service (VTS) which use the ground-based radar system have some difficulties in detecting moving ships due to the limited detection range. A virtual vessel traffic control system is introduced to contribute to prevent a marine accident such as collision and stranding from happening. Existing VTS has its limit. The virtual vessel traffic control system consists of both data acquisition by satellite remote sensing and a simulation of traffic environment stress based on the satellite data, remotely sensed data. And it could be used to provide timely and detailed information about the marine safety, including the location, speed and direction of ships, and help us operate vessels safely and efficiently. If environmental stress values are simulated for the ship information derived from satellite data, proper actions can be taken to prevent accidents. Since optical sensor has a high spatial resolution, JERS satellite data are used to track ships and extract their information. We present an algorithm of automatic identification of ship size and velocity. This paper lastly introduce the field testing results of ship detection by RADARSAT SAR imagery, and propose a new approach for a Vessel Monitoring System(VMS), including VTS, and SAR combination service.

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An Implementation of Sensing Data Management System based on Embedded System (임베디드 시스템 기반의 센싱 데이터 관리 시스템 구현)

  • Lim, Ji-Eon;Choi, Shin-Hyeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.9
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    • pp.3441-3445
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    • 2010
  • In the modern information society, computational tasks such as business processes in addition to numerous amounts of information from various sensor devices exist. In this paper, an embedded system based on sensing data management system which can collect and store sensing data from sensor node is developed. Berkeley DB and the query processor is installed in the main system, by using this we can send the more accurate information to the host server and can increase the reliability of sensor information.

A Comparative Review of the Satellite Remote Sensing (위성원격탐사에 관한 비교법적 고찰)

  • Kim, Young-Ju
    • The Korean Journal of Air & Space Law and Policy
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    • v.35 no.1
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    • pp.203-319
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    • 2020
  • The regulation of satellite remote sensing is generally included with the scope of statutes governing outer space activities. But not all states opted for dedicated satellite remote sensing regulation. The decision whether to do so depends in part on the specific capabilities of national satellite remote sensing programs. Five states that have dedicated statutes governing operations with remote sensing data are the United States, with its developed Landsat regime (the Land Remote Sensing Policy Act of 1992, LRSPA), Canada, with its Remote Sensing Systems Act, Germany, with its Satellite Data Securities Protection Act (SatDSiG), France, with its Law on Space Operations (LOS), Japan, with its Act on Ensuring Appropriate Handling of Satellite Remote Sensing Data. The major purpose of this article is to shed light on some legal issues surrounding remote sensing activities by comparative review. The paper analyzes international conventions or soft law and national law and policies relating to satellite remote sensing. It also offers some implications and suggestions for regulations of satellite remote sensing operations and satellite data.

Attack-Proof Cooperative Spectrum Sensing Based on Consensus Algorithm in Cognitive Radio Networks

  • Liu, Quan;Gao, Jun;Guo, Yunwei;Liu, Siyang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.6
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    • pp.1042-1062
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    • 2010
  • Cooperative spectrum sensing (CSS) is an effective technology for alleviating the unreliability of local spectrum sensing due to fading/shadowing effects. Unlike most existing solutions, this paper considers the use of CSS technology in decentralized networks where a fusion center is not available. In such a decentralized network, some attackers may sneak into the ranks of cooperative users. On the basis of recent advances in bio-inspired consensus algorithms, an attack-proof, decentralized CSS scheme is proposed in which all secondary users can maintain cooperative sensing by exchanging information locally instead of requiring centralized control or data fusion. Users no longer need any prior knowledge of the network. To counter three potential categories of spectrum sensing data falsification (SSDF) attacks, some anti-attack strategies are applied to the iterative process of information exchange. This enables most authentic users to exclude potentially malicious users from their neighborhood. As represented by simulation results, the proposed scheme can generally ensure that most authentic users reach a consensus within the given number of iterations, and it also demonstrates much better robustness against different SSDF attacks than several existing schemes.

Reservation and Status Sensing Multiple Access Protocol in Slotted CDMA Systems

  • Lim, In-Taek;Ryu, Young-Tae
    • Journal of information and communication convergence engineering
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    • v.8 no.5
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    • pp.513-518
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    • 2010
  • This paper proposes a medium access control protocol for integrated voice and data services in slotted CDMA systems. The proposed protocol, which is named as RCSSMA (Reservation Code and Status Sensing Multiple Access), adopts a code reservation and status sensing schemes. RCSSMA protocol gives higher access priority to the voice traffic than data traffic for reducing the packet dropping probability. The voice terminal reserves an available spreading code to transmit voice packets during a talkspurt, whereas the data terminal transmits a packet over one of the available spreading codes that are not reserved by the voice terminals. In this protocol, the voice packets never contend with the data packets. Packet dropping probability and average data packet transmission delay are analyzed using a Markov chain model.

REMOTE SENSING L.T.A PLATFORM

  • Onda, Masahiko
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.1047-1052
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    • 1989
  • A novel multi-purpose monitoring platform-LTA vehicle is presented with much improved kinetic performances together with its structural analysis and its scale model test data. This provides a useful mean of monitoring, exploring and remote sensing platform that flies over the wide range of atmosphere and can be used as a safe economic device.

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A Traffic and Link Quality Based Congestion Control Scheme for Reliable Sensing Data Delivery in Wireless Sensor Networks (무선 센서 네트워크에서 신뢰성 있는 센싱 정보 전달을 위한 트래픽 및 링크 품질 기반 혼잡 제어 기법)

  • Kim, Sungae;Chung, Sanghwa
    • Journal of KIISE:Information Networking
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    • v.41 no.4
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    • pp.177-185
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    • 2014
  • It has been occurred many times that wireless sensor networks (WSNs) had congested areas because all the sensing data collected by multiple sensor nodes are delivered to one sink node. Typically, in order to control congested areas, it used to reduce the traffic by increasing the sensing period or discarding packets. However, those schemes have a disadvantage that it loses the reliability when delivering sensing data. Moreover, there are no schemes considering case of having poor quality of links between nodes in practical terms. In this paper, we suggest a scheme not to reduce the traffic but to distribute the traffic by changing routing paths depends on the traffic and the quality of links. Also, it can be seen that the reliability of delivering of the sensing data is improved with the experiments improving collection rates and shortening end-to-end delay.

Characterization and modeling of a self-sensing MR damper under harmonic loading

  • Chen, Z.H.;Ni, Y.Q.;Or, S.W.
    • Smart Structures and Systems
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    • v.15 no.4
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    • pp.1103-1120
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    • 2015
  • A self-sensing magnetorheological (MR) damper with embedded piezoelectric force sensor has recently been devised to facilitate real-time close-looped control of structural vibration in a simple and reliable manner. The development and characterization of the self-sensing MR damper are presented based on experimental work, which demonstrates its reliable force sensing and controllable damping capabilities. With the use of experimental data acquired under harmonic loading, a nonparametric dynamic model is formulated to portray the nonlinear behaviors of the self-sensing MR damper based on NARX modeling and neural network techniques. The Bayesian regularization is adopted in the network training procedure to eschew overfitting problem and enhance generalization. Verification results indicate that the developed NARX network model accurately describes the forward dynamics of the self-sensing MR damper and has superior prediction performance and generalization capability over a Bouc-Wen parametric model.

Closed-loop structural control with real-time smart sensors

  • Linderman, Lauren E.;Spencer, Billie F. Jr.
    • Smart Structures and Systems
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    • v.16 no.6
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    • pp.1147-1167
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    • 2015
  • Wireless smart sensors, which have become popular for monitoring applications, are an attractive option for implementing structural control systems, due to their onboard sensing, processing, and communication capabilities. However, wireless smart sensors pose inherent challenges for control, including delays from communication, acquisition hardware, and processing time. Previous research in wireless control, which focused on semi-active systems, has found that sampling rate along with time delays can significantly impact control performance. However, because semi-active systems are guaranteed stable, these issues are typically neglected in the control design. This work achieves active control with smart sensors in an experimental setting. Because active systems are not inherently stable, all the elements of the control loop must be addressed, including data acquisition hardware, processing performance, and control design at slow sampling rates. The sensing hardware is shown to have a significant impact on the control design and performance. Ultimately, the smart sensor active control system achieves comparable performance to the traditional tethered system.

Improvement Method for Human Body Sensing Module and Managing System (인체 감지 센서 모듈 및 관리 시스템의 개선 방안)

  • Ahn, Tae-Won
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.10
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    • pp.223-227
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    • 2014
  • This paper presents an improvement method for human body sensing module and management system, specifically focused on the human body detection module with ultrasonic sensors to detect the usage of toilets and the management system to control the state of the toilets of the entire building. The proposed human body sensing module consists of the detection sensor to detect the movement of human body and the contact sensor to detect the position in a certain distance. The management system is configured of the control unit to process the signal transmitted from sensors, opening and closing valves according to the sensing signal, and the short range wireless communication unit to save the operational status data as well as transmit the data at regular intervals.