• Title/Summary/Keyword: Infra Red

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A $64\times64$ IRFPA CMOS Readout IC for Uncooled Thermal Imaging (비냉각 열상장비용 $64\times64$ IRFPA CMOS Readout IC)

  • 우회구;신경욱;송성해;박재우;윤동한;이상돈;윤태준;강대석;한석룡
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.36C no.5
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    • pp.27-37
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    • 1999
  • A CMOS ReadOut Integrated Circuit (ROlC) for InfraRed Focal Plane Array (IRFPA) detector is presented, which is a key component in uncooled thermal imaging systems. The ROIC reads out signals from $64\times64$ Barium Strontium Titanate (BST) infrared detector array, then outputs pixel signals sequentially after amplifying and noise filtering. Various design requirements and constraints have been considered including impedance matching, low noise, low power dissipation and small detector pitch. For impedance matching between detector and pre~amplifier, a new circuit based on MOS diode structure is devised, which can be easily implemented using standard CMOS process. Also, tunable low pass filter with single~pole is used to suppress high frequency noise. In additions, a clamping circuit is adopted to enhance the signal~to-noise ratio of the readout output signals. The $64\times64$ IRFPA ROIC is designed using $0.65-\mu\textrm{m}$ 2P3M (double poly, tripple metal) N~Well CMOS process. The core part of the chip contains 62,000 devices including transistors, capacitors and resistors on an area of about $6.3-mm\times6.7-mm$.

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Structural Charateristics of Silk Fibroin Gel on The Preparation Conditions (Silk Fibroin Gel의 제조조건에 따른 구조특성)

  • Lee, Kwang-Gill;Lee, Young-Woo;Yeo, Joo-Hong;Nam, Jin;Kweon, Hae-Young;Park, Young-Hwan
    • Journal of Sericultural and Entomological Science
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    • v.41 no.1
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    • pp.41-47
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    • 1999
  • Silk fibroin dissolved in highly concentrated calcium chloride and ethanol mixture aqueous solution turned into gel under suitable conditions. Preparation conditions and properties of gel were investigated as a function of parameters such as pH of solution, fibroin concentration, glycerol concentration and molecular weight. When pH of silk fibroin aqueous solution was near the isoelectronic point(pH 3.9~4.0), gelation occurred rapidly and strength of gel was stonger than that of pH-unadjusted due to electrostatic repulsion decrease between silk fibroin macromolecules. As concentration of silk fibroin and glycerol was higher, gelation occurred more rapid. FT Infra-red spectra of freeze-dried fibroin gel showed that gelation was derived by intermolecular anti-parallel ${\beta}$-sheet structure formation. In addition to, it was found that white-precipitate occurred instead of gelation when aqueous silk fibroin was treated by enzyme(flavouzyme), however, after flavouzyme-treated silk fibroin aqueous solution was centrifugated gelation occurred instantly. The results of differential scanning thermal analysis and infra-red spectroscopy showed that thermal stability and crystallinity of enzyme-hydrolyzed fibroin are superior to those of unhydrolyzed fibroin.

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Characteristics of Polysaccharide Extracted from the Cultured Mycelia of Schizophyllum commune (치마버섯 균사체 배양물로부터 분리한 다당류의 이화학적 특성)

  • Lee, June-Woo;Kim, Yong-Seok
    • The Korean Journal of Mycology
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    • v.37 no.1
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    • pp.91-95
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    • 2009
  • To examine physico-chemical properties of the polysaccharide extracted from liquid-cultured mycelia of Schizophyllum commune, each the polysaccharide was extracted with hot water treatment and then fractionated with ethanol, alkaline solution and ultrafiltration. And we determined carbohydrate contents, composition of amino acids, infra-red spectrum and viscosity. Carbohydrate contents of polysaccharide treated with ethanol and ultrafiltration were 72.0% and 62.3%, and proteins content were 15.3% and 32.0% respectively. The carbohydrate consisted of four monosaccharides and the protein contained 16 amino acids. The polysaccharide obtained from ultrafiltration was shown an absorption band characteristic of the ${\beta}$-glycosidic linkage by infra red spectra. These results suggest that the polysaccharide extracted from Schizophyllum commune showed the characteristics of proteinbounded polysaccharide, and it was ${\beta}$-glycosidic linkage with strong viscosity.

Bactericidal Application and Cytotoxic Activity of Biosynthesized Silver Nanoparticles with an Extract of the Red Seaweed Pterocladiella capillacea on the HepG2 Cell Line

  • El Kassas, Hala Yassin;Attia, Azza Ahmed
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.3
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    • pp.1299-1306
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    • 2014
  • Background: Nano-biotechnology is recognized as offering revolutionary changes in various fields of medicine. Biologically synthesized silver nanoparticles have a wide range of applications. Materials and Methods: Silver nanoparticles (AgNPs) were biosynthesized with an aqueous extract of Pterocladiella (Pterocladia) capillacea, used as a reducing and stabilizing agent, and characterized using UV-VIS spectroscopy, Fourier Transform Infra red (FT-IR) spectroscopy, transmission electron microscopy (TEM) and energy dispersive analysis (EDX). The biosynthesized AgNPs were tested for cytotoxic activity in a human hepatocellular carcinoma ($HepG_2$) cell line cultured in Dulbecco's modified Eagle medium supplemented with 10% fetal bovine serum, 1% antibiotic and antimycotic solution and 2 mM glutamine. Bacterial susceptibility to AgNPs was assessed with Staphylococcus aureus, Bacillus subtilis [Gram+ve] and Pseudomonas aeruginosa and Escherichia coli [Gram-ve]. The agar well diffusion technique was adopted to evaluate the bactericidal activity of the biosynthesized AgNPs using Ampicillin and Gentamicin as gram+ve and gram-ve antibacterial standard drugs, respectively. Results: The biosynthesized AgNPs were $11.4{\pm}3.52$ nm in diameter. FT-IR analysis showed that carbonyl groups from the amino acid residues and proteins could assist in formation and stabilization of AgNPs. The AgNPs showed potent cytotoxic activity against the human hepatocellular carcinoma ($HepG_2$) cell line at higher concentrations. The results also showed that the biosynthesized AgNPs inhibited the entire panel of tested bacteria with a marked specificity towards Bacillus subtillus. Conclusions: Cytotoxic activity of the biosynthesized AgNPs may be due to the presence of alkaloids present in the algal extract. Our AgNPs appear more bactericidal against gram-positive bacteria (B. subtillus).

EVALUATION FOR DAMAGED DEGREE OF VEGETATION BY FOREST FIRE USING LIDARAND DIGITALAERIAL PHOTOGRAPH

  • Kwak, Doo-Ahn;Chung, Jin-Won;Lee, Woo-Kyun;Lee, Seung-Ho;Cho, Hyun-Kook;We, Gwang-Jae;Kim, Tae-Min
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.533-536
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    • 2007
  • The LiDAR data structure has the potential for modeling in three dimensions because the LiDAR data can represent voxels with z value under certain defined conditions. Therefore, it is possible to classify the physical damaged degree of vegetation by forest fire as using the LiDAR data because the physical loss of canopy height and width by forest fire can be relative to an amount of points reached to the ground through the canopy of damaged forest. On the other hand, biological damage of vegetation by forest fire can be explained using the NDVI (Normalized Difference Vegetation Index) which show vegetation vitality. In this study, we graded the damaged degree of vegetation by forest fire in Yangyang-Gun of South Korea using the LiDAR data for physical grading and digital aerial photograph including Red, Green, Blue and Near Infra-Red bands for biological grading. The LiDAR data was classified into 2 classes, of which one was Serious Physical Damaged (SPD) and the other was Light Physical Damaged (LPD) area. The NDVI was also classified into 2 classes which are Serious Biological Damaged (SBD) and Light Biological Damaged (LBD) area respectively. With each 2 classes ofthe LiDAR data and NDVI, the damaged area by forest fire was graded into 4 degrees like damaged class 1,2,3 and 4 grade. As a result of this study, 1 graded area was the broadest and next was the 3 grade. With this result, we could know that the burned area by forest fire in Yangyang-Gun was damaged rather biologically because the NDVI in 1 and 3 grade appeared low value whereas the LiDAR data in 1 and 3 grade included light physical damage like the LPD.

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A Study on Pre-evaluation of Tree Species Classification Possibility of CAS500-4 Using RapidEye Satellite Imageries (농림위성 활용 수종분류 가능성 평가를 위한 래피드아이 영상 기반 시험 분석)

  • Kwon, Soo-Kyung;Kim, Kyoung-Min;Lim, Joongbin
    • Korean Journal of Remote Sensing
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    • v.37 no.2
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    • pp.291-304
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    • 2021
  • Updating a forest type map is essential for sustainable forest resource management and monitoring to cope with climate change and various environmental problems. According to the necessity of efficient and wide-area forestry remote sensing, CAS500-4 (Compact Advanced Satellite 500-4; The agriculture and forestry satellite) project has been confirmed and scheduled for launch in 2023. Before launching and utilizing CAS500-4, this study aimed to pre-evaluation the possibility of satellite-based tree species classification using RapidEye, which has similar specifications to the CAS500-4. In this study, the study area was the Chuncheon forest management complex, Gangwon-do. The spectral information was extracted from the growing season image. And the GLCM texture information was derived from the growing and non-growing seasons NIR bands. Both information were used to classification with random forest machine learning method. In this study, tree species were classified into nine classes to the coniferous tree (Korean red pine, Korean pine, Japanese larch), broad-leaved trees (Mongolian oak, Oriental cork oak, East Asian white birch, Korean Castanea, and other broad-leaved trees), and mixed forest. Finally, the classification accuracy was calculated by comparing the forest type map and classification results. As a result, the accuracy was 39.41% when only spectral information was used and 69.29% when both spectral information and texture information was used. For future study, the applicability of the CAS500-4 will be improved by substituting additional variables that more effectively reflect vegetation's ecological characteristics.

The evaluation of correction methods and effect of kaolinite on quantitative analysis of quartz in respirable dust by FTIR direct-on-filter method (직접필터법을 이용한 석영 분석시 고령석의 영향 및 보정방법 평가)

  • Phee, Young Gyu
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.19 no.1
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    • pp.1-7
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    • 2009
  • To establish the Fourier-Transform Infra-Red spectrophotometry(FTIR) Direct-On-Filter(DOF) technique as a useful analytical method for quartz in respirable dust samples, an influence of the kaolinite should be corrected. Respirable dust, created in a dust chamber containing the standard material of quartz and kaolinite were collected using a cyclone equipped with a 25 mm, $0.8\;{\mu}m$ pore size DM filter as a collection medium. This study was designed to compare three methods of correction for kaolinite when quantifying the content of quartz, including the least square, the optimum choice and the spectral subtraction methods. The content of quartz in the respirable dust samples was overestimated by 6.2% when mixed with kaolinite(35.5% by weight). The content of quartz containing kaolinite(72.8% by weight) were overestimated by 32%. The spectral subtraction method underestimated the quartz content by 1.5%, while the other two correction methods, the optimum choice and the least square method, overestimated the quartz content by 1.9% to 6.4% and 0.04 to 1.1%, respectively. The results of this study are suggested that, when correcting for effects of kaolinite on quantitative analysis of quartz in respirable dust by FTIR direct-on-filter method, the least square method produce the most unbiased results be compared with those of other correction methods.

ON MEASURING THE WELDING TEMPERATURE OF CONNECTOR

  • Deng Jyh-jeng
    • Proceedings of the Korean Society for Quality Management Conference
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    • 1998.11a
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    • pp.361-377
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    • 1998
  • The measurement of welding temperature of connector is usually performed with an infra red temperature gauge. However, the factors, which influence the temperature measurement, are rarely known. This research used the welding temperature measurement of the connector as an example, applying the experimental design, in two-phase experiments, to search the affecting factors. In phase-I experiment, we used a resolution III, seven-factor fractional factorial design with two levels for each factor. The result showed that none of the factor was significant in affecting the welding temperature when the type I error ${\alpha}$ was 0.05. Next, we did the phase-II factorial experiment with three factors and each factor had three levels. The experiment showed the experimental time was significant in affecting the temperature measurement when the type I error ${\alpha}$ was 0.05. Further Duncan's multiple range tests on the second experimental data showed that the later the experimental time, the weaker the light intensity could have on the temperature measurement and the average of the highest temperatures was lower. Moreover, the later the experimental time, the smaller was the variance of the temperature measurement and the difference between the averages of the highest and the lowest temperatures was also lower.

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A Study on the Infrared Signature of a Naval Ship under the Marine Climate (함정 표면 적외선 신호에 대한 해양기상 영향분석)

  • Kim, Yoon-Sik
    • Journal of the Society of Naval Architects of Korea
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    • v.49 no.3
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    • pp.264-272
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    • 2012
  • A study on the IR(InfraRed) signature of a naval ship has been performed using well known IR signature analysis software, ShipIR/NTCS. Variations of the IR signature radiated from skins of a naval ship have been investigated according to the monthly averaged marine climate conditions. An unclassified destroyer model with and without applying the washdown system was applied to compare the influence on the signature under the background changes. The marine background models were created from the observed data by a buoy of Korea Meterological Administration(KMA). The sensitivity of the ship signature against the climate variables such as air temperature, sea temperature, relative humidity has been studied as well. The seasons which show extreme(max, min) skin signature change by whether the washdown is applied or not. The sensitivities of the air temperature and the sea temperature for a dry-ship reversed by applying the washdown on the ship surfaces.

A study on enhancement of heterogeneous noisy image quality for the performance improvement of target detection and tracking (표적 탐지/추적 성능 향상을 위한 불균일 미세 잡음 영상 화질개선 연구)

  • Kim, Y.;Yoo, P.H.;Kim, D.S.
    • Journal of Korea Multimedia Society
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    • v.17 no.8
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    • pp.923-936
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    • 2014
  • Images can be contaminated with different types of noise, for different reasons. The neighborhood averaging and smoothing by image averaging are the classical image processing techniques for noise removal. The classical spatial filtering refers to the aggregate of pixels composing an image and operating directly on these pixels. To reduce or remove effectively noise in image sequences, it usually needs to use noise reduction filter based on space or time domain such as method of spatial or temporal filter. However, the method of spatial filter can generally cause that signals of objects as the target are also blurred. In this paper, we propose temporal filter using the piece-wise quadratic function model and enhancement algorithm of image quality for the performance improvement of target detection and tracking by heterogeneous noise reduction. Image tracking simulation that utilizes real IIR(Imaging Infra-Red) images is employed to evaluate the performance of the proposed image processing algorithm.