• 제목/요약/키워드: DO Sensor

검색결과 1,218건 처리시간 0.024초

An Integrated Approach for Position Estimation using RSSI in Wireless Sensor Network

  • Pu, Chuan-Chin;Chung, Wan-Young
    • Journal of Ubiquitous Convergence Technology
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    • 제2권2호
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    • pp.78-87
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    • 2008
  • Received signal strength indicator (RSSI) is used as one of the ranging techniques to locate dynamic sensor nodes in wireless sensor network. Before it can be used for position estimation, RSSI values must be converted to distances using path loss model. These distances among sensor nodes are combined using trilateration method to find position. This paper presents an idea which attempts to integrate both path loss model and trilateration as one algorithm without going through RSSI-distance conversion. This means it is not simply formulas combination but a whole new model was developed. Several advantages were found after integration: it is able to reduce processing load, and ensure that all values do not exceed the maximum range of 16-bit signed or unsigned numbers due to antilog operation in path loss model. The results also show that this method is able to reduce estimation error while inaccurate environmental parameters are used for RSSI-distance conversion.

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무선 센서노드를 이용한 지능형 캠퍼스 차량 관리 시스템 구현 (Implementation of Intelligent Campus Vehicle Management System Using Wireless Sensor Nodes)

  • 최준영;양현호
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2007년도 추계 종합학술대회 논문집
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    • pp.193-196
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    • 2007
  • 최근 무선 통신 기술과 초소형화 기술의 진보로 지능형 센서 (smart sensor)를 이용한 무선 센서 네트워크의 구축이 가능해 졌으며 무선 센서 네트워크를 우리 생활 전반에 걸친 다양한 분야에 응용하려는 연구가 활발하게 진행되고 있다[1]. 본고에서는 무선 센서 네트워크의 응용분로서 무선센서노드를 활용한 캠퍼스 차량 관리 시스템 구축 방안에 대하여 기술하였다. 이를 위하여 무선센서노드의 전송전력제어 및 개별 노드 인식 방안을 고찰하였으며 실제 적용 시스템의 구성 및 동작 절차를 제안하였다.

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Evaluation of Two Types of Biosensors for Immunoassay of Botulinum Toxin

  • Choi, Ki-Bong;Seo, Won-Jun;Cha, Seung-Hee;Choi, Jung-Do
    • BMB Reports
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    • 제31권1호
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    • pp.101-105
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    • 1998
  • Immunoassay of botulinum toxin (BTX) B type was investigated using two typed of biosensors: light addressable potentiometric sensor (LAPS) and surface plasmon resonance (SPR) sensor. Urease-tagged and immuno-filtration capture method have been used for LAPS. Tag-free and direct binding real-time detection method have been used for SPR sensor. The detection limit of sandwich assay format with LAPS was 10 ng/ml, which was the lowest among methods tested. SPR has the advantage of being more convenient because tag-free direct binding assay can be used and reaction time was reduced, regardless of low sensitivity. This result shows that sandwich assay format with LAPS can be used as an alternative method of BTX mouse bioassay which is known as the most sensitive method for the detection of BTX.

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에너지 변환을 이용한 근접센서에의 적용 (Application of Proximity Sensor using Energy Transformation)

  • 이용제;이교성;김도훈;오세호;김양모
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 합동 추계학술대회 논문집 정보 및 제어부문
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    • pp.237-240
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    • 2002
  • We have studied a RF energy transformation. In this paper, we introduced proximity sensor using RF energy transformation. We used 125kHz RF signal as carrier frequency and BPSK circuit, PNP proximity sensor and designed circuit to transmit to the reader through the antenna with data which sensor had acquired. Micro-controller, oscillator, power amp, FSK Modulation module are included in the circuit. Max 323 chip is applied to analog switch and used to HYP-30R10NA sensor chip.

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자외선조사에 의한 다공질 실리콘 알코올 센서의 감도 개선 (Improvement of Sensitivity in Porous Silicon Alcohol Gas Sensors by UV Light)

  • 김성진;최복길
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제48권9호
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    • pp.676-680
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    • 1999
  • To do breath alcohol measurement, a sensor is necessary that it can detect low alcohol gas concentration of 0.01% at least. In this work, a capacitance-type alcohol gas sensor using porous silicon layer is developed to measure low alcohol gas concentration. The sensor using porous silicon layer has some sensitivity at room temperature by very large effective surface area, but there is still much room for improvement. In this experiment, we measured the capacitance of the sensor under 254 nm UV light on the porous silicon layer, in which alcohol solution was kept in a flask at 25, 35, and $45^{\circ}C$ by a heater. As the result, the improvement of sensitivity by illuminating UV light was observed. The increasing rate of the capacitance was shown to be double more than those measured under UV-off state. It is supposed that UV light activates response of the oriental and interfacial polarizations which have slow relaxation time for AC field.

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자율적 상호협동을 통한 모바일 센서의 자기위치파악 (Autonomous Cooperative Localization of Mobile Sensors)

  • 송하윤
    • 정보처리학회논문지A
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    • 제17A권2호
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    • pp.53-62
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    • 2010
  • 모바일 센서 네트워크(Mobile Sensor Network)의 노드(Node)인 모바일 센서 차량(Mobile Sensor Vehicles)들은 특정 지역에 관해 획득한 정보를 서로 교환하고 통합하는 과정을 거쳐 자신의 위치를 파악하게 되는데 이를 지역화(localization)라 한다. 이때 모바일 센서 차량은 탑재된 각종 센서를 이용하여 자신의 위치 정보를 파악한다. 본 연구에서는 데드-레코닝(Dead-Reckoning), 컴퓨터 비전 기법, 그리고 RSSI(Received Signal Strength Identification)를 사용한 모바일 센서 차량(MSV)의 지역화 정밀도를 향상시키는 방안을 제시하고, 각각의 방식들이 가진 장점을 융합하여 보다 정밀한 지역화를 할 수 있는지 살펴본다.

Design and Implementation of Vehicle Hazard Lamp Automatic Operation System Using Acceleration Sensor

  • Lee, Sang-Ryeol
    • 한국컴퓨터정보학회논문지
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    • 제25권6호
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    • pp.91-98
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    • 2020
  • 급제동 시 추돌사고를 방지하기 위하여 비상등 자동작동 기능이 없는 기존 차량에 손쉽게 추가장착이 가능한 비상등 자동작동 시스템을 제안하였다. 급제동을 인식하기 위해서는 몇 가지 방법이 있지만 GPS를 사용하면 시스템이 터널에서 작동하지 않으며 차량 속도 센서를 사용하면 기존 차량에 시스템을 추가로 설치하기 어렵다. 따라서 제안한 시스템은 가속도 센서를 사용하여 이러한 문제점들을 제거하고 차량의 급회전 및 급바운스도 인식 할 수 있도록 하였다.

첨단자동차의 전자파 내성 실험 환경에 관한 연구: 카메라 센서를 중심으로 (Electromagnetic Immunity Test Environments of Advanced Vehicles with Camera Sensor Systems)

  • 우현구
    • 자동차안전학회지
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    • 제12권4호
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    • pp.7-12
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    • 2020
  • Recently, automobile industries have developed ADAS, smart cars, connected cars, automated driving systems, which use a variety of sensor systems - ultrasonics, cameras, lidars and radars - and communication systems. It is necessary to examine the electromagnetic immunity of vehicles equipped with the sensor systems due to the fact that the normal operation of those systems is very important to the safety of the vehicles. The electromagnetic immunity tests are carried out in an electromagnetic semi anechoic chamber, which is cut off from the outside. It is difficult to create test environments in which the camera sensor systems of vehicles work properly in the test chamber. In this study, test jigs were designed and tested and as a result they are shown to be effective to create test environments for electromagnetic immunity tests of vehicles equipped with camera sensors. We also proposed additional safety standards for immunity tests of vehicles with camera systems that currently do not exist.

마그네틱 픽업 방식의 CPS 신호 해석 회로에 관한 연구 (A Study of the Circuit for CPS Signal Using Magnetic Pickup)

  • 주용완;조봉수;백광렬
    • 제어로봇시스템학회논문지
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    • 제17권1호
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    • pp.1-5
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    • 2011
  • The basic signals for electronic engine control are velocity and degree of the engine cam shaft. The CPS sensor used for this signal and magnetic pick-up type CPS sensor is more popular. It is very important thing analyze this signal correctly. If there are some mistakes at the analysis, like a noise, The engine do not working at the best status, it will generate some noise, emit exhaust fumes and waste more gases. In general way to analysis this signal, you use zero-level detector circuit and in order to reduce the error you must use another sensor like a TDC sensor. In this paper, We proposed the analysis method using electronics circuits for magnetic pick-up type CPS sensor. We designed Comparison level detector circuit, Differential circuit and Full-rectifier circuit for detected the Long tooth and Short tooth level correctly without another sensor. We expected it is useful for more reliable engine control.