• 제목/요약/키워드: sensing system

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Cognitive Radio 시스템을 위한 열악한 통신 환경에서 효과적인 에너지 검출방법 (Efficient Energy Detection Method in Poor Radio Environment for Cognitive Radio System)

  • 현영주;김경석
    • 한국콘텐츠학회논문지
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    • 제7권7호
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    • pp.60-67
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    • 2007
  • 주파수 대역의 사용 유무를 판단하는데 스펙트럼 센싱의 결과는 중요하다. 스펙트럼 센싱은 CR 시스템에서 주파수 대역을 확인하는 역할을 한다. 본 논문에서 에너지 검출 기반의 센싱 기법에 자기상관함수를 적용하여 제안하였다. 이는 수신된 신호에 자기 상관함수를 적용하여 에너지 검출기반의 성능을 향상시켰다. 이 방법은 평균 및 자기 상관함수와 같은 확률적인 파라메터들이 시간에 따라 주기적으로 변하는 특성을 갖는 Cycolstationary 프로세서와는 다른 접근 방법이다. 본 논문에서 제안된 센싱 방법은 열악한 통신환경에서 보다 효과적일 것이다. 만약 CR 시스템에서 유휴주파수 대역을 찾기 위한 센싱 과정에 본 논문에서 제안한 방법을 적용하면, 에너지 검출기반의 센싱 기법의 장점인 구조적 간단함과 빠른 스펙트럼 검출 결과를 얻을 수 있을 것이다.

Incentive Mechanism in Participatory Sensing for Ambient Assisted Living

  • Yao, Hu;Muqing, Wu;Tianze, Li
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권1호
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    • pp.159-177
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    • 2018
  • Participatory sensing is becoming popular and has shown its great potential in data acquisition for ambient assisted living. In this paper, we propose an incentive mechanism in participatory sensing for ambient assisted living, which benefits both the platform and the mobile devices that participated in the sensing task. Firstly, we analyze the profit of participant and platform, and a Stackelberg game model is formulated. The model takes privacy, reputation, power state and quality of data into consideration, and aims at maximizing the profit for both participant and publisher. The discussion of properties of the game show that there exists an unique Stackelberg equilibrium. Secondly, two algorithms are given: one describes how to reach the Stackelberg equilibrium and the other presents the procedures of employing the incentive strategy. Finally, we conduct simulations to evaluate the properties and effectiveness of the proposed mechanism. Simulation results show that the proposed incentive mechanism works well, and the participants and the publisher will be benefitted from it. With the mechanism, the total amount of sensory data can be maximized and the quality of the data can be guaranteed effectively.

Forest Environment Monitoring Application of Intelligence Embedded based on Wireless Sensor Networks

  • Seo, Jung Hee;Park, Hung Bog
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권4호
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    • pp.1555-1570
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    • 2016
  • For monitoring forest fires, a real-time system to prevent fires in wider areas should be supported consistently. However, there has still been a lack of the support for real-time system related to forest fire monitoring. In addition, the 'real-time' processing in a forest fire detection system can lead to excessive consumption of energy. To solve these problems, the intelligent data acquisition of sensing nodes is required, and the maximum energy savings as well as rapid and accurate detection by flame sensors need to be done. In this regard, this paper proposes a node built-in filter algorithm for intelligent data collection of sensing nodes for the rapid detection of forest fires with focus on reducing the power consumption of the remote sensing nodes and providing efficient wireless sensor network-based forest environment monitoring in terms of data transmission, network stability and data acquisition. The experimental result showed that battery life can be extended through the intelligent sampling of remote sensing nodes, and the average accuracy of the measurement of flame detection based on the distance is 44%.

ATSC DTV 신호 검출 성능 (Performance of Spectrum Sensing for ATSC DTV Signals)

  • 이소영;김은철;김진영
    • 한국인터넷방송통신학회논문지
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    • 제10권3호
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    • pp.167-172
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    • 2010
  • 본 논문은 ATSC DTV (advanced television system committee digital television) 신호를 검출하기 위해 고속 퓨리에 변환 (FFT : fast Fourier transform) 기반의 파일럿 신호를 검출하는 알고리즘의 성능을 파라미터를 변화시켜가면서 분석하였다. DTV 신호를 검출하기 위한 요구사항을 분석하였으며, 센싱 회수 및 시간에 따라서 성능을 비교하였다. 실험 결과 센싱 횟수가 증가할수록 신호 검출 성능이 향상되는 것을 확인할 수 있었다. 본 논문의 결과는 DTV 주파수 대역의 인지 라디오 (CR : cognitive radio) 시스템을 구현하는데 참고자료로 활용될 수 있다.

원격 상수도관망 누수감지 시스템에 관한 연구 (A Study on a Remote Leakage Sensing System in Waterworks Network)

  • 강병모;홍인식
    • 정보처리학회논문지D
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    • 제11D권6호
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    • pp.1311-1318
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    • 2004
  • 인구증가와 발전으로 도시 집중화 현상에 따라 수도의 수요증가가 가속화되는 상태이다. 특히 물 부족현상 및 수질악화로 인한 수원확보도 어려워지고 있는 실정이다. 누수로 인한 막대한 손실을 줄이고자 컴퓨터와 인터넷을 이용하여 누수가 발생할 경우, 누수 여부를 판단하고 중앙 모니터링 센터에서 관리할 수 있는 시스템이 필요하다. 본 논문에서는 누수감지관과 TDR을 이용한 원격 상수도관망 누수 감지 시스템을 제안하였다. 유효성을 입증하기 위해 300mm 3-레이어 강관으로 파이로트 시스템을 구축하여 시뮬레이션 하였다.

분포형 광음향센싱 기반 부분방전 모니터링 기술 연구 (Partial Discharge Monitoring Technology based on Distributed Acoustic Sensing)

  • 김희운;이주영;정효영;김영호;김명진
    • 센서학회지
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    • 제31권6호
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    • pp.441-447
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    • 2022
  • This study describes a novel method for detecting and measuring partial discharge (PD) on an electrical facility such as an insulated power cable or switchgear using fiber optic sensing technology, and a distributed acoustic sensing (DAS) system. This method has distinct advantages over traditional PD sensing techniques based on an electrical method, including immunity to electromagnetic interference (EMI), long range detection, simultaneous detection for multiple points, and exact location. In this study, we present a DAS system for PD detection with performance evaluation and experimental results in a simulated environment. The results show that the system can be applied to PD detection.

Acyl-Homoserine lactone Quorum Sensing in Bactreria

  • Greenberg, E.Peter
    • Journal of Microbiology
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    • 제38권3호
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    • pp.117-121
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    • 2000
  • Recent advances in studies of bacterial gene expression and light microscopy show that cell-to cell communication and communication and community behavior are the rule rather than the exception. One type of cell-cell communication, quorum sensing in Gram-negative bacteria involves acyl-homoserine lactone signals. This type of quorum sension represents a dedicated communication system that enables a given species to sense when it has reached a critical population density. and to respond by activating expression of specific genes. The LuxR and LuxI proteins of Vibrio fisheri are the founding members of the acyl-homoserine lactone quorum sensing signal receptor and signal generator families of proteins. Acyl-homeserine lactone signaling in Pseudomonas aeruginosa is one model for the relationship between quorum sensing community behavior, and virulence. In the P. aeruginosa model. quorum sensing is required for normal biofilm maturation and virulence. There are multiple quorum-sensing circuits that control the expression of dozens of specific genes in P. aeruginosa.

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THE PAN OCEAN REMOTE SENSING CONFERENCE ASSOCIATION --- OUR GREETING TO THE FULL CONFERENCE ISRS2006PORSEC

  • Katsaros, Kristina B.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.3-6
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    • 2006
  • This presentation delivers the Appreciation of the The Pan Ocean Remote Sensing Conference Association for the cooperation with the Korean Society of Remote Sensing in organizing a joint conference with the International Symposium of Remote Sensing. It includes a brief history of the PORSEC Association with its mission and aims and the system of governance of the organization. Our vision for the future, is presented from this president's point of view. It includes a discussion of building expert capacity to use remote sensing techniques in developing nations by the sharing of knowledge and our ability to promote predictability of natural hazards with our workshops and science sessions. The article ends with an appreciation of our many sponsors.

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Performance Analysis of Amplify and Forward (AF)-based Cooperative Spectrum Sensing in Cognitive Radio Networks

  • Khan, Muhammad Sajjad;Koo, Insoo
    • Journal of information and communication convergence engineering
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    • 제11권4호
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    • pp.223-228
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    • 2013
  • Cognitive radio has been recently considered a promising technology to improve spectrum utilization by enabling secondary access to licensed bands that are not used by primary users temporarily or spatially. A prerequisite to this secondary access is the lack of interference to the primary system. This requirement makes spectrum sensing a key process for cognitive radio. In this study, we consider amplify and forward (AF)-based cooperative spectrum sensing for cognitive radio networks where multiple relay nodes are utilized to amplify and forward the primary user signal for better spectrum sensing, and maximum ratio combining is used for fusion detection by a cognitive coordinator. Further, the detection probability and the bit error rate of AF-based cooperative spectrum sensing are analyzed in fading multiple cognitive relay channels. The simulation results show that the AF-based cooperative spectrum sensing scheme outperforms the conventional scheme.

Short Review on Quartz Crystal Microbalance Sensors for Physical, Chemical, and Biological Applications

  • Il Ryu, Jang;Hoe Joon, Kim
    • 센서학회지
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    • 제31권6호
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    • pp.389-396
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    • 2022
  • Quartz crystal microbalance (QCM) based sensors are used for various applications owing to advantages such as excellent accuracy and precision, rapid response, and tiny footprint. Traditional applications of QCM-based sensors include biological sensing and thin-film thickness monitoring. Recently, QCMs have been used as functional material for novel physical and chemical detections, and with improved device design. QCM-based sensors are garnering considerable attention in particulate matter sensing and electric nose application. This review covers the challenges and solutions in physical, chemical, and biological sensing applications. First, various physical sensing applications are introduced. Secondly, the toxic gas and chemical detection studies are outlined, focusing on introducing a coating method for uniform sensing film and sensing materials for a minimal damping effect. Lastly, the biological and medical sensing applications, which use the monomolecularly decorating method for biomolecule recognition and a brief description of the overall measuring system, are also discussed.