• 제목/요약/키워드: sensing characteristics

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인공위성 원격탐사 정보의 활용 (Application of Spaceborne Earth Remote Sensing Information)

  • 가민호
    • 대한원격탐사학회지
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    • 제16권3호
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    • pp.261-279
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    • 2000
  • 오늘날 저궤도 및 정지궤도 인공위성에 탑재하여 운용되고있는 원격탐사 장비는 관련기술의 급속한 발전에 힘입어 현재 그 수요가 계속 증가하고있는 추세이다. 2000년까지 약 15개 국가에서 위성탑재 원격탐사 시스템 보유계획을 갖고있으며 운용되는 인공위성이 수십개에 이를것으로 예상된다. 국내에서도 우주개발 계획에따라 탐사위성이 계속 발사될 예정이며 응용분야또한 광범위하여 파급효과 또한 클것이다. 원격탐사 정보를 사회 제반 분야에 효과적으로 응용한다는 것은 잠정적 수요자가 지구 원격탐사시스템의 정보, 임무 및 동작특성과 접한다는 것을 의미하나 현재 국내상황으로볼 때 이와관련된 내용들이 더 보충되어야할 필요성이 있는 것이 사실이다. 이를위하여 본 총설에서는 현재 운용되고있거나 계획도어있는 미국, 러시아 및 기타국가의 지구원격탐사 시스템의 정보 활용에 대하여 살펴보려하며 내용의 범위는 대중적 정보수요가 있는 응용분야, 임무 및 시스템으로 국한하였다. 아울러 본 총설의 많은 부분은 참고문헌을 편술한 내용을 참고로 하였음을 밝혀둔다.

Radiometric Characteristics of KOMPSAT EOC Data Assessed by Simulating the Sensor Received Radiance

  • Kim, Jeong-Hyun;Lee, Kyu-Sung;Kim, Du-Ra
    • 대한원격탐사학회지
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    • 제18권5호
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    • pp.281-289
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    • 2002
  • Although EOC data have been frequently used in several applications since the launch of the KOMPSAT-1 satellite in 1999, its radiometric characteristics are not clear due to the inherent limitations of the on-board calibration system. The radiometric characteristics of remotely sensed imagery can be measured by the sensitivity of radiant flux coming from various surface features on the earth. The objective of this study is to analyze the radiometric characteristics of EOC data by simulating the sensor- received radiance. Initially, spectral reflectance values of reference targets were measured on the ground by using a portable spectre-radiometer at the EOC spectrum. A radiative transfer model, LOWTRAN, then simulated the sensor-received radiance values of the same reference target. By correlating the digital number (DN) extracted from the EOC image to the corresponding radiance values simulated from LOWTRAN, we could find the radiometric calibration coefficients for EOC image. The radiometric gain coefficients of EOC are very similar to those of other panchromatic optical sensors.

해상 풍력자원평가를 위한 원격탐사자료의 활용 (Practical Application of Remote-Sensing Data for Offshore Wind Resource Assessment)

  • 김현구;황효정;경남호
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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    • pp.319-320
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    • 2008
  • This paper introduces remote-sensing data which can be practically applied for offshore wind resource assessment. Development of offshore wind energy is inevitable for Korea to achieve the national dissemination target of renewable energy, i.e., 5% uptil 2010. However, the only available offshore in-situ measurement, marine buoy data would not represent areal wind characteristics. Consequently, remote-sensing technology has been started to apply to offshore wind resource assessment and is actively developing. Among them, NCAR/NCEP reanalysis dataset, QuikSCAT blended dataset, and offshore wind retrieval from SAR imagery are briefly summarized in this paper.

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Characteristics of Chlorophyll a Absorption in Case 2 Water for Using Remote Sensing Data

  • Islam, Monirul;Sado, Kimiteru
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1-3
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    • 2003
  • In this study, spectroradiometer data were coupled with fluorometer data to find out the best suited bands ratio to monitor the chlorophyll a concentration for inland water. Remote sensing reflectance measurements were used to evaluate the performance of several default ocean color chlorophyll algorithms for SeaWiFS data. This study shows that the chlorophyll a concentration from fluorometer and reflectance from spectroradiometer lies in exploiting the signal provided by the chlorophyll a red absorption peak near 670nm. Two-band ratio based on a ratio of reflectance 670 and 700nm provided a good correlation for a linear model, compare with blue-green two band ratio.

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Feasibility study of wide-band low-profile ultrasonic sensor with flexible piezoelectric paint

  • Li, Xin;Zhang, Yunfeng
    • Smart Structures and Systems
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    • 제4권5호
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    • pp.565-582
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    • 2008
  • This paper presents a feasibility study of flexible piezoelectric paint for use in wide-band low-profile surface-mount or embeddable ultrasonic sensor for in situ structural health monitoring. Piezoelectric paint is a piezoelectric composite with 0-3 connectivity. Because of its ease of application, piezoelectric paint can be readily fabricated into sensing element with complex pattern. This study examines the characteristics of piezoelectric paint in acoustic emission signal and ultrasonic guided wave sensing. A series of ultrasonic tests including pitch catch and pencil break tests were performed to validate the ultrasonic wave sensing capability of piezoelectric paint. The results of finite element simulation of ultrasonic wave propagation, and acoustic emission generated by a pencil lead break on an aluminum plate are also presented in this paper along with corresponding experimental data. Based on the preliminary experimental results, the piezoelectric paint appears to offer a promising sensing material for use in real-time monitoring of crack initiation and propagation in both metallic and composite structures.

A Robust Resistive Fingerprint Sensor

  • Jung, Seung-Min
    • Journal of information and communication convergence engineering
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    • 제7권1호
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    • pp.66-71
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    • 2009
  • A novel sensing scheme using resistive characteristics of the finger is proposed. ESD problem is more harmful than a capacitive fingerprint sensor in a resistive fingerprint sensor, because the sensor plate is directly connected to the sensing cell. The proposed circuit is more robust than conventional circuit for ESD. The sensor plate and sensing cell are isolated by capacitor. The pixel level simple detection circuit is fully digital operation unlike that of the capacitive sensing cell. The sensor circuit blocks are designed and simulated in a standard CMOS $0.35{\mu}m$ process. The proposed circuit is more stable and effective than a typical circuit.

부하감지시스템을 사용한 굴삭기의 유압제어특성 시뮬레이션 (A Simulation on the Hydraulic Control Characteristics of Excavator Using Load Sensing System)

  • 조승호
    • 한국정밀공학회지
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    • 제15권2호
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    • pp.134-145
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    • 1998
  • The purpose of this paper is to construct a computer simulation system which can analyze and design the hydraulic excavator Theoretical analyses are performed on the hydraulic circuit and attachment of excavator with load sensing system. Databases are constructed for control valve opening areas, horsepower control and for load sensing regulator. For hydraulic components modularized programming techniques are applied which is expected to be utilized for software development of fluid power system. Through simulation an information of any point in hydraulic circuit can be obtained.

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MOSFET을 이용한 전동기 구동을 위한 저가격형 전류검출법 (A Low-Cost Current-Sensing Scheme for MOSFET Motor Drives)

  • 장성동;정재호;박종규;이균정;신휘범
    • 전력전자학회논문지
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    • 제8권1호
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    • pp.40-47
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    • 2003
  • A low-cost current-sensing scheme for the motor drives with MOSFET is described. Many motor drives usually employ the common current sensors to measure current for the purpose of control or protection. These current sensors, however, significantly burden the power circuit with the size and cost. The proposed current-sensing scheme utilizes information concerning MOSFET's On-voltage and On-resistance. An analogue circuit detecting On-voltage can overcome the above disadvantages because the circuit is small and is made at a low cost, and the fuzzy inference for On-resistance is also simply designed based on MOSFET's characteristics. The validity of this scheme will be experimentally verified by adopting the current control of a battery car.

가속도 값 변화에 따른 HH 스마트센서의 센싱능력 평가 (Estimation of the Sensing Ability of HH Smart Sensor According to Acceleration Value Changing)

  • 황성연;홍동표;박준홍
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 추계학술대회논문집A
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    • pp.527-532
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    • 2001
  • In this paper, we will propose the new method that estimates the sensing ability of HH smart sensor. We have developed a new signal processing method that can distinguish among different materials relatively. The HH smart sensor was developed for recognition of materials. We made the HH smart sensor in our experiment. Then, we estimated the ability to recognize objects according to acceleration value. We estimated the sensing ability of HH smart sensor with the $R_{SAI}$ method. Experiments and analysis were executed to estimate the ability to recognize objects according to acceleration value changing. Dynamic characteristics of HH smart sensor were evaluated relatively through a new $R_{SAI}$ method that uses the power spectrum density. Applications of this method are for finding abnormal conditions of objects (auto-manufacturing), feeling of objects (medical product), robotics, safety diagnosis of structure, etc.

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주파수 변화에 따른 지적센서의 대상물 인식능력 분석 (Analysis of the Ability of Recognize Objects for Smart Sensor According to Frequency Changing)

  • 황성연;홍동표;강희용;박준홍
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 추계학술대회 논문집
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    • pp.23-26
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    • 2000
  • This paper descrtbcs our prlmary study for a new mncthod of recogninng materials. which is need for precision work system. This IS a study of dynarnlc characteristics of sensor. new melhod ($R_{SAI}$) has thc sensing ability of distinguishing materials. Experiment and annlysis are executed for proper dynamic scnslng condition. First. we developed advanced smart sensor Second, we develop new methods that have a sensing ability of distinguish matarialsAccording to frequency changing. mtluence of smart sensor are evaluated through new recognition Index ($R_{SAI}$) that ratioof sensing ability index. Disungush of object is cxucuted wllh RsA, method relalivcly according to liequency changing. Wecan use the RsAl for finding materids. Applfciltionr of thls method are linding abnormal condition of obicct (automanufacturing).keling ofobject (medlcal product). tobolics, safety diagnosis of structure, etc

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