• 제목/요약/키워드: digital sensing

검색결과 922건 처리시간 0.031초

Effects of spatial resolution on digital image to detect pine trees damaged by pine wilt disease

  • Lee, Seung-Ho;Cho, Hyun-Kook
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.260-263
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    • 2005
  • This study was carried out to investigate the effects of spatial resolutions on digital image for detecting pine trees damaged by pine wilt disease. Color infrared images taken from PKNU-3 multispectral airborne photographing system with a spatial resolution of 50cm was used as a basic data. Further test images with spatial resolutions of 1m, 2m and 4m were made from the basic data to test the detecting capacity on each spatial resolution. The test was performed with visual interpretation both on mono and stereo modus and compared with field surveying data. It can be conclude that it needs less than 1m spational resolutions or 1m spatial resolutions with stereo pair in order to detect pine trees damaged by pine wilt disease.

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Low-Voltage Current-Sensing CMOS Interface Circuit for Piezo-Resistive Pressure Sensor

  • Thanachayanont, Apinunt;Sangtong, Suttisak
    • ETRI Journal
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    • 제29권1호
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    • pp.70-78
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    • 2007
  • A new low-voltage CMOS interface circuit with digital output for piezo-resistive transducer is proposed. An input current sensing configuration is used to detect change in piezo-resistance due to applied pressure and to allow low-voltage circuit operation. A simple 1-bit first-order delta-sigma modulator is used to produce an output digital bitstream. The proposed interface circuit is realized in a 0.35 ${\mu}m$ CMOS technology and draws less than 200 ${\mu}A$ from a single 1.5 V power supply voltage. Simulation results show that the circuit can achieve an equivalent output resolution of 9.67 bits with less than 0.23% non-linearity error.

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압축센싱 기반의 무선통신 시스템

  • 르나탄;신요안
    • 전자공학회지
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    • 제38권1호
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    • pp.56-67
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    • 2011
  • As a result of quickly growing data, a digital transmission system is required to deal with the challenge of acquiring signals at a very high sampling rate, Fortunately, the CS (Compressed Sensing or Compressive Sensing) theory, a new concept based on theoretical results of signal reconstruction, can be employed to exploit the sparsity of the received signals. Then, they can be adequately reconstructed from a set of their random projections, leading to dramatic reduction in the sampling rate and in the use of ADC (Analog-to-Digital Converter) resources. The goal of this article is provide an overview of the basic CS theory and to survey some important compressed sensing applications in wireless communications.

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FOREST MONITORING PROTOTYPE SYSTEM USING WEB MAPPING TECHNOLOGY

  • Kawahito, Shinobu;Kuroiwa, Kaori;Sobue, Shin-ichi;Ochiai, Osamu
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.793-794
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    • 2003
  • Forest fire monitoring prototype system was developed by National Development Agency of Japan (NASDA) and the Ministry of Agriculture, Forestry and Fisheries of Japan (MAFF) to verify the usefulness of interoperabile system to study new services of Earth observation satellite data distribution for a practical application. In this system, a standard interface of Web based GIS technology, OpenGIS Consortium (OGC) technology, was adopted. This system is also expected to encourage data sharing activities in Digital Asia Network (DAN) as a demonstration system.

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Assessing Sea Surface Temperature in the Yellow Sea Using Satellite Remote Sensing Data

  • Lee, Kyoo-seock;Kang, Hee-Sook
    • 대한원격탐사학회지
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    • 제6권1호
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    • pp.39-47
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    • 1990
  • The first Marine Observation Satellite(MOS) was launched by National Space Development Agency of Japan on February 19, 1987, and it is equipped with three sensons covering visible, infrared, and microwave region. One of them is Visible and Thermal Infrared Radiometer(VTIR) whose main objective is to detect the Sea Surface Temperature(SST). The objective of this study was to process the MOS data using Cray-2 supercomputer, and to assess the SST in the Yellow Sea. In order to implement this objective, the linear regression model between the ground truth data and the corresponding digital number of VTIR in MOS was used to establish the relationship. After testing the significance of the regression model, the SST map of the whole Yellow Sea was derived based on the model. The digital SST map representing the study area showed certain pattern about the SST of Yellow Sea in March and April. In conclusion, the VTIR data in MOS is also useful in investigating SST which provides the information about the Yellow Sea water current in the spring.

압축 감지 기술과 무선통신 응용 (Compressed Sensing and the Applications of Wireless Communications)

  • 황대성;김대성;최진호;하정석
    • 대한전자공학회논문지SP
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    • 제46권5호
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    • pp.32-39
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    • 2009
  • Compressed Sensing (이하 압축 감지 기술)은 Nyquist 률 이하로 아날로그 신호를 샘플 할 수 있는 기법이다. 이 기법으로 신호는 기존의 신호 샘플 방법보다 적은 수의 측정값으로 표현이 가능하며 또한 선형 프로그래밍을 이용하여 측정값으로부터 본래 신호를 높은 확률로 복원할 수 있다. 이를 통해 압축 감지 기술은 같은 신호를 획득하는데 소모되는 측정 시간 및 ADC (analog-to-digital converter) 자원의 양을 크게 감소시키는 장점을 갖는다. 본 논문에서는 압축 감지 기술에 대한 기본적인 개념과 임의 기저를 이용하여 아날로그 신호로부터 측정값을 획득하는 방법과 본래 신호를 복원하는 방법에 대해 설명하고 무선통신 분야에서의 압축 감지 기술 응용 예시를 소개한다.

압축센싱 디지털 수신기 신호처리 로직 구현 (Signal Processing Logic Implementation for Compressive Sensing Digital Receiver)

  • 안우현;송장훈;강종진;정웅
    • 한국군사과학기술학회지
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    • 제21권4호
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    • pp.437-446
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    • 2018
  • This paper describes the real-time logic implementation of orthogonal matching pursuit(OMP) algorithm for compressive sensing digital receiver. OMP contains various complex-valued linear algebra operations, such as matrix multiplication and matrix inversion, in an iterative manner. Xilinx Vivado high-level synthesis(HLS) is introduced to design the digital logic more efficiently. The real-time signal processing is realized by applying dataflow architecture allowing functions and loops to execute concurrently. Compared with the prior works, the proposed design requires 2.5 times more DSP resources, but 10 times less signal reconstruction time of $1.024{\mu}s$ with a vector of length 48 with 2 non-zero elements.

저전력 센싱 알고리즘을 활용한 무선 디지털 수도 계량기 시스템 (A Wireless Digital Water Meter System using Low Power Sensing Algorithm)

  • 은성배;신강욱;이영우;오승엽
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제15권5호
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    • pp.315-321
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    • 2009
  • U-city 등에서 원격 디지털 수도 검침 시스템의 수요가 증가하고 있다. 디지털 수도 미터는 센서의 종류에 따라 다양한데 홀센서를 사용한 방식은 정밀도가 높다는 장점이 있으나 기존의 알고리즘은 전력소모가 큰 것이 단점이다. 본 논문에서는 정밀도를 유지하면서 저전력 소모를 추구하는 센싱 알고리즘을 제시한다. 우리의 방식은 물의 사용 여부를 정밀도는 떨어지나 전력소모가 작은 홀센서를 이용하여 센싱하는 것이다. 물이 사용되기 시작하면 정밀도가 높은 홀 센서를 사용하여 사용량을 계측한다. 우리의 알고리즘이 기존의 방식보다 전력소모를 2배 가량 줄일 수 있음을 분석을 통하여 보였다.

Two-step Holographic Imaging Method based on Single-pixel Compressive Imaging

  • Li, Jun;Li, Yaqing;Wang, Yuping;Li, Ke;Li, Rong;Li, Jiaosheng;Pan, Yangyang
    • Journal of the Optical Society of Korea
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    • 제18권2호
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    • pp.146-150
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    • 2014
  • We propose an experimental holographic imaging scheme combining compressive sensing (CS) theory with digital holography in phase-shifting conditions. We use the Mach-Zehnder interferometer for hologram formation, and apply the compressive sensing (CS) approach to the holography acquisition process. Through projecting the hologram pattern into a digital micro-mirror device (DMD), finally we will acquire the compressive sensing measurements using a photodiode. After receiving the data of two holograms via conventional communication channel, we reconstruct the original object using certain signal recovery algorithms of CS theory and hologram reconstruction techniques, which demonstrated the feasibility of the proposed method.

Monitoring Flood Disaster Using Remote Sensing Data

  • Chengcai, Zhang;Xiuwan, Chen;Gaolong, Zhu;Wenjiang, Zhang;Peng, Sun-Chun
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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    • pp.280.2-286
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    • 1998
  • Flood is the main natural disaster mostly in the world. It is a care problem to prevent flood disaster generally. The frequency of flood disaster is high and the distributing field is wide, the 50 percent population and 70 percent properties distribute at the threaten field of flood disaster in China. Flood disaster has caused a huge amount of economical losses and these losses have an increasing trend. Along with the development of reducing natural disaster action, it has become one of the most attentive problems for monitoring flood, preventing flood and forecasting flood efficiently. Remote sensing has the characteristics of large spatial observing areas, wide spectrum ranges, and imaging far away from the targets, imaging capabilities all weather. Spatial remote sensing information, which records the full, processes of the disaster's occurrence and development in real-time. It is a scientific basis for management, planning and decision-making. Through systemic analyzing the RS monitoring theory, based on compounding RS information, the technology and method of monitoring flood disaster are studied.

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