• Title/Summary/Keyword: Radiation sensor

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The Color Enhancement of TV Picture by the Color Measurement of Illumination (광원의 색채 계측에 의한 TV 화상의 색 향상)

  • 이응주;정인갑;박양우;이광춘;하영호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.1
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    • pp.47-58
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    • 1996
  • An object color can be seen differently under the various outer illuminants. However, human visual system has color constnacy that the object color can be seen constantly under the different outer illuminants. When the viewer watches TV under specific that the object color can be seen constantly under the different outer illuminants. When the viewer bathes TV under specific outer illuminants, he perceives distortes color due to the emitting specturm of outer illuminants as well as the radiation of CPT itself. Namely, when the outer illuminants such as fluorescent and incandescent lamps incident on CPT, brightness, saturation, hue, itself. Namely, when the outer iluminants such as fluorescent and incandescent lamps incident on CPT, brightness, saturation, hue, and contrast on color pictures are changend, he perceives distortedcolr fromthe original color. In this paper color enhancement algorithm based on light intensity and outer light decision funtion using RGB sensor was proposed. The implemented TV of proposed algorithm has higher visual quality at the view point of human visual system and more vivid than that ofcoventional color TV.

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Actuator multiple control method for greenhouse environment control system (온실 환경 제어시스템을 위한 액추에이터 복합 제어 방법)

  • Son, Kyo-Hoon;Park, Dae-Heon;Kim, Se-Han;Kim, Jae-Hyung;Jeung, Eun-Tae
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.11 no.2
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    • pp.39-45
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    • 2012
  • In recent years the USN(Ubiquitous Sensor Networks) technology has been applied in the greenhouse in order to control temperature and humidity automatically. In this paper, we proposed a control algorithm using feedback linearization techniques based on a mathematical model for temperature and humidity environment. Especially, Control algorithm is presented to the operation of the ventilator affecting on the temperature and humidity system at the same time. The System has been designed taking into account the disturbance(External temperature, soil temperature, external humidity, solar radiation and wind). In conclusion, I will present a way to control multiple actuator through simulations. The proposed control algorithm is validated using the Matlab/Simulink tools.

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High Pressure X-ray Diffraction Studies on a Natural Talc (천연산 활석에 대한 고압 X-선 회절연구)

  • 김영호;이지은
    • Journal of the Mineralogical Society of Korea
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    • v.12 no.1
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    • pp.1-10
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    • 1999
  • Talc (Mg3Si4O10(OH)2), one of the sheet silicate minerals, which is the hydrothermal alteration product of serpentinite at Cheongarm mine was prepared for the high pressure compressibility studies. Energy dispersive X-ray diffraction experiment was carried out using the Synchrotron Radiation with the Mao-Bell type diamond anvil cell at room temperature. Polycrystalline talc was mixed with MgO powder for pressure sensor as well as pressure medium in the sample chamber. High pressure runs were performed at pressures up to 35.2 GPa. Talc shows no phase transition within the present high pressure region. Bulk modulus of this talc was determined by the Birch-Murnaghan equation of state to be 78 GPa assuming its first pressure derivative Ko' of 4.

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OPTICAL PROPERTIES OF ASIAN DUST ESTIMATED FROM GROUND BASED POLARIZATION MEASUREMENTS

  • KUSAKA Takashi;NISHISAKA Tomoya
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.385-387
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    • 2005
  • Polarimetric measurements of the sky radiation by the PSR-I000, which is the multi-spectral polarimeter developed by the Opt Research Corporation and has the same wavelength regions (443nm, 490nm, 565nm, 670nm, 765nm and 865nm) as the ADEOSII/POLDER sensor, have been carried out at the ground station in Kanazawa city, Japan from March to May. First of all, the wavelength dependency of degrees of polarization is examined and it is shown that degrees of polarization measured under the hazy dust cloud are lower than those measured in the clear sky and decrease as the wavelength increases. Next, a new method for estimating optical properties, such as the optical thickness, the number size distribution and the refractive index, of the Asian dust and the ground reflectance from degrees of polarization measured by PSR-I000 is described. Finally, this method is applied to polarization data acquired on April 15,2002. As a result, it is shown that our estimation algorithm provides a good result.

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Coaxial Feed Wideband CP antenna for RFID Applications

  • Park, Kyu-Dae;Kim, Hwan-Yong
    • Journal of information and communication convergence engineering
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    • v.6 no.4
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    • pp.391-395
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    • 2008
  • Wideband terminal and base station is required to serve not only existing 1st and 2nd generation mobile communication systems but also 3rd generation systems. In this paper, we present a feasibility study on coaxial feed compact wideband antenna for UHF RFID reader application. The original antenna was designed for partial discharge detection sensor in high voltage diagnostic system. However, we modified the original prototype to achieve shifted down resonant frequency for wideband wireless communication applications. The experimental result shows good return loss characteristics and radiation patterns except for the total gain at each resonant frequency. The maximum measured gain was 2.45 dBi$\sim$3.18 dBi at 910MHz.

Recent Developments Involving the Application of Infrared Thermal Imaging in Agriculture

  • Lee, Jun-Soo;Hong, Gwang-Wook;Shin, Kyeongho;Jung, Dongsoo;Kim, Joo-Hyung
    • Journal of Sensor Science and Technology
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    • v.27 no.5
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    • pp.280-293
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    • 2018
  • The conversion of an invisible thermal radiation pattern of an object into a visible image using infrared (IR) thermal technology is very useful to understand phenomena what we are interested in. Although IR thermal images were originally developed for military and space applications, they are currently employed to determine thermal properties and heat features in various applications, such as the non-destructive evaluation of industrial equipment, power plants, electricity, military or drive-assisted night vision, and medical applications to monitor heat generation or loss. Recently, IR imaging-based monitoring systems have been considered for application in agricultural, including crop care, plant-disease detection, bruise detection of fruits, and the evaluation of fruit maturity. This paper reviews recent progress in the development of IR thermal imaging techniques and suggests possible applications of thermal imaging techniques in agriculture.

Single Feed Compact Wideband Antenna for Wireless Communication Applications

  • Park, Noh-Joon;Kang, Young-Jin
    • Journal of information and communication convergence engineering
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    • v.6 no.2
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    • pp.164-168
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    • 2008
  • Wideband terminal and base station is required to serve not only existing 1st and 2nd generation mobile communication systems but also 3rd generation systems. In this paper, we presents a feasibility study on single feed compact wideband antenna for wireless communication applications including GSM (890-960 MHz), GPS (1575 MHz), DCS (1710-1880 MHz), PCS (1880-1990 MHz), UMTS (1900-2200 MHz), ISM (2400-2480 MHz), IMT2000 and satellite DMB bands. The original antenna was designed for partial discharge detection sensor in high voltage diagnostic system. However, we modified the original prototype to achieve shifted down resonant frequency for wideband wireless communication applications. The experimental result shows good return loss characteristics and radiation patterns except for the total gain at each resonant frequency. The maximum measured gain was 2.45 dBi${\sim}$3.18 dBi at 1710 MHz${\sim}$1880 MHz.

The Comparison of X-ray Response Characteristics of Vacuum Evaporated (진공증착된 CdTe와 $Cd_{0.85}Zn_{0.15}Te$ 필름의 X선 반응특성 비교)

  • Kang, S.S.;Choi, J.Y.;Cha, B.Y.;Moon, C.W.;Kim, J.H.;Nam, S.H.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.845-848
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    • 2002
  • The study of photoconductor materials is demanded for development for flat-panel digital x-ray Imager. In this paper, We investigated the feasibility of application as x-ray image sensor using Cd(Zn)Te compound with high stopping power on high radiation. These Cd(Zn)Te samples were fabricated by vacuum thermal evaporation method to large area deposition and investigated I-V measurement as applied voltage. The experimental results show that the additional injection Zn in CdTe film reduced the leakage current, for the $Cd_{0.85}Zn_{0.15}Te$ detector, the net charge had the highest value as $144.58pC/cm^2$ at 30 V.

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A Study on the Preparation of $MgB_4O_7$ Thermoluminescent Phosphors and X-ray Dosimetry ($MgB_4O_7$ 열형광체의 제작과 X선의 선량측정에 관한 연구)

  • Song, Jea-Heung;Noh, Kyung-Suk;Lee, Deog-Kyu;Koo, Hyo-Geun
    • Journal of radiological science and technology
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    • v.21 no.2
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    • pp.47-52
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    • 1998
  • Tissue-equivalent $MgB_4O_7$ TL phosphors were prepared and the effects of Lantanides series activators on TLD properties of the phosphors were studied. The glow curve of TLD increased TL intensity and the peak temperature is low that is, the heating rate is $10^{\circ}C/sec$. The activation energy of the main peak estimated by the peak shape method. By these methods, the estimated activation energies were $0.76{\sim}1.55eV$ respectively. The TL phosphors prepared in this work may be utilized to radiation sensor elements because of this high sensitivity to X-ray.

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Sea surface temperature estimation from remote measurement of the thermal radiation

  • Mima, Kazuhiko;Satoh, Makoto;Moriyama, Masao;Ishimatsu, Takakazu
    • 제어로봇시스템학회:학술대회논문집
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    • 1994.10a
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    • pp.12-15
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    • 1994
  • To establish the sea surface temperature estimation scheme for the upcoming advanced remote sensor, the quasi-analytical solution of the approximated radiative transfer equation which express the radiative transfer process of the radiant energy radiated from the sea surface to the satellite is approximated into the non-linear equation. To solve the simultaneous approximated radiative transfer equation which express the radiative transfer process of the radiant energy radiated from the sea surface to the satellite is approximated into the nonlinear equation. To solve the simultaneous approximated radiative transfer equation at each channel, the constrained non-linear optimization technique is adopted. To define the coefficients of the approximated radiative transfer equation and the constraints, the satellite detected radiance and the total transmittance are computed from the 1350 kinds of simulated atmosphere / surface models via radiative transfer code. The verification from the simulated data show the sufficient result.

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