• Title/Summary/Keyword: Infrared(IR)

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Study on Infrared Signature Variations of a Naval Ship Operated at sea Near Geoje-do Island (거제도 인근해상에서 운용되는 함정의 적외선 신호 변화 특성에 대한 연구)

  • Kil, Tae-Jun;Kim, Tae-Kuk
    • Journal of the Korea Institute of Military Science and Technology
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    • v.17 no.1
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    • pp.15-24
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    • 2014
  • It is essential to understand the infrared signature of a naval ship to survive against various missile attacks under variable environmental conditions. As guided missiles are developing to equip more accurate IR seekers, research works for countermeasure and IR stealth technology are strongly required. But challenging works are continuously suggested for predicting and analyzing IR signal status of naval ships to achieve low observable performance under various weather conditions, variable missions and developing threats. In this study, overall guidelines of setting design criteria for low observable ships are proposed by considering varying environmental conditions including daily and seasonal variations. Test and evaluation criteria for newly constructed ships for target and background temperature difference is proposed as a design criteria which can be predicted by change of condition and ship's speed. Through the proposed techniques and procedures, it is expected to establish the measurement and evaluation criteria by using temperature, IR Signal differences between the ship and the background.

Surface-enhanced infrared detection of benzene in air using a porous metal-organic-frameworks film

  • Kim, Raekyung;Jee, Seohyeon;Ryu, Unjin;Lee, Hyeon Shin;Kim, Se Yun;Choi, Kyung Min
    • Korean Journal of Chemical Engineering
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    • v.36 no.6
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    • pp.975-980
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    • 2019
  • Infrared (IR) spectroscopy is a powerful technique for observing organic molecules, as it combines sensitive vibrational excitations with a non-destructive probe. However, gaseous volatile compounds in the air are challenging to detect, as they are not easy to immobilize in a sensing device and give enough signal by themselves. In this study, we fabricated a thin nanocrystalline metal-organic framework (nMOF) film on a surface plasmon resonance (SPR) substrate to enhance the IR vibration signal of the gaseous volatile compounds captured within the nMOF pores. Specifically, we synthesized nanocrystalline HKUST-1 (nHKUST-1) particles of ca. 80 nm diameter and used a colloidal dispersion of these particles to fabricate nHKUST-1 films by a spin-coating process. After finding that benzene was readily adsorbed onto nHKUST-1, an nHKUST-1 film deposited on a plasmonic Au substrate was successfully applied to the IR detection of gaseous benzene in air using surface-enhanced IR spectroscopy.

Rapid discrimination of commercial strawberry cultivars using Fourier transform infrared spectroscopy data combined by multivariate analysis

  • Kim, Suk Weon;Min, Sung Ran;Kim, Jonghyun;Park, Sang Kyu;Kim, Tae Il;Liu, Jang R.
    • Plant Biotechnology Reports
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    • v.3 no.1
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    • pp.87-93
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    • 2009
  • To determine whether pattern recognition based on metabolite fingerprinting for whole cell extracts can be used to discriminate cultivars metabolically, leaves and fruits of five commercial strawberry cultivars were subjected to Fourier transform infrared (FT-IR) spectroscopy. FT-IR spectral data from leaves were analyzed by principal component analysis (PCA) and Fisher's linear discriminant function analysis. The dendrogram based on hierarchical clustering analysis of these spectral data separated the five commercial cultivars into two major groups with originality. The first group consisted of Korean cultivars including 'Maehyang', 'Seolhyang', and 'Gumhyang', whereas in the second group, 'Ryukbo' clustered with 'Janghee', both Japanese cultivars. The results from analysis of fruits were the same as of leaves. We therefore conclude that the hierarchical dendrogram based on PCA of FT-IR data from leaves represents the most probable chemotaxonomical relationship between cultivars, enabling discrimination of cultivars in a rapid and simple manner.

Quantitative Assessment of Infrared Analysis of Concrete Admixtures

  • Casale, Anthony J. III;Doukakis, Johanna;Najm, Husam;Davis, Kimberly
    • International Journal of Concrete Structures and Materials
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    • v.7 no.3
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    • pp.203-214
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    • 2013
  • This study investigates quantitative methods for assessment of infrared analysis of concrete admixtures using correlation coefficients by performing IR scans following the ASTM C494/C494M-11 specifications. In order to achieve this goal, numerous IR scans were performed on specimens supplied by the manufacturer from different batches to ensure uniformity and equivalency. These scans were then analyzed to create correlation coefficients for each admixture. The correlation coefficients were used to quantitatively evaluate and interpret IR Scans of job samples. The study focused on 23 most commonly used concrete admixtures by the New Jersey Department of Transportation (NJDOT). They include air-entrainers, accelerators, retarders, water reducers, and other combinations of these admixtures. Their correlation coefficients were established by analyzing a total of 12 scans of each admixture from three different batches supplied by the manufacturer at different time intervals. In order to validate the obtained correlation coefficients and establish a target correlation, job samples were tested and compared to the obtained correlations. The study also evaluated the effects of drying time and using different types of KBr on correlation coefficients.

A Study on the Properties and Fabrication of Bulk Forming GeSe Based Chalcogenide Glass for Infrared Optical Lens (적외선 광학렌즈 제작을 위한 GeSe의 벌크 제작 및 특성 연구)

  • Bae, Dong-Sik;Yeo, Jong-Bin;Park, Jung-Hoo;Lee, Hyun-Yong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.26 no.9
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    • pp.641-645
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    • 2013
  • Chalcogenide glass has superior property of optical transmittance in the infrared region. Glass made using Ge-Se how many important optical applications. We have determined the composite formular of $Ge_{0.25}Se_{0.75}$ to be the GeSe chalcogenide glass composition appropriate for IR lenses. Also, the optical, thermal and physical characteristics of chalcogenide glass depended on the composition ratio. GeSe bulk sample is produced using the traditional melt-quenching method. The optical, structural, thermal and physical properties of the compound were measured by using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Differential scanning calorimeter (DSC), and Scanning electron microscope (SEM) respectively.

Smoothness of the Zodiacal Light and Emission from the AKARI North Ecliptic Pole Monito rObservations

  • Pyo, Jeong-Hyun;Matsumoto, Toshio;Tange, Tsutomu;Jeong, Woong-Seob;Matsuhara, Hideo;Matsuura, Shuji;Wada, Takehiko;Seo, Hyun-Jong;Hong, Seung-Soo
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.2
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    • pp.52.1-52.1
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    • 2010
  • The Japanese infrared (IR) space mission AKARI monitored the brightness in the fields very close to the north ecliptic pole (NEP) with nine wavebands in Infrared Camera (IRC), which cover the wavelength range from 2 to $24{\mu}m$. We reduced the NEP monitor observations and examined the smoothness of the sky background brightness. Our analysis shows that the background brightness is smooth over a frame of about $10'\times10'$ within about 0.1% deviation in mid-IR. Because the zodiacal light (ZL) and emission (ZE) dominate the diffuse sky brightness in the near- and mid-IR wavelengths, the background brightness varies with season through a year. We tried sinusoidal fittings to the observed NEP background brightness. The fitting analysis shows that the sine function is successful in describing the seasonal variation of the ZL and ZE within 2% deviations from the observed brightness, especially for the 15, 18, and $24{\mu}m$ bands, within 0.3%. These results will provide limits and caveats for the studies of the cosmic infrared background radiation.

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Korean Secondary Students' Conceptions about Visible light, Ultra Violet and Infrared Ray (가시광선, 자외선과 적외선에 대한 학생들의 개념)

  • Han, Shin;Park, Tae-Yoon;Jeong, Sophia Sun Kyung
    • Journal of the Korean Society of Earth Science Education
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    • v.8 no.1
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    • pp.35-44
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    • 2015
  • The purpose of this paper is to identify the conceptions of middle school and high school students about visible light, Ultra violet(UV) and Infrared ray(IR). We administered questionnaire 40 people of middle school 3rd students and 43 people of high school 2nd students in Gyeonggi-do. Misconceptions about visible light, UV and Ir were observed in many students. The results of study are as follows: Firstly, Many students think that it is possible to see objects without visible light. The explanations given by students for the visiblity of objects in darkness indicates a heavy reliance on personal experiences. Secondly, we have confirmed that high school students well understand the fact that the object reflects the light. However, a significant number of students exhibited an eye-centered perspective of vision. Thirdly, students had a variety of ideas about the meaning of the term UV and IR. Analysis of questionnaire data indicates that many students believe that it is possible to see objects in the presence of UV light alone.

Positioning of a Leader Robot in a Leader-Follower Robot Using Low-Cost Infrared(IR) Distance Sensors (저가형 적외선 거리 센서를 이용한 선도-추종 로봇시스템에서 선도로봇의 위치인식)

  • Sanjaakhand, Battuya;Jang, Moon-Suk;Cha, Dong-Hyuk
    • Journal of IKEEE
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    • v.24 no.1
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    • pp.275-283
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    • 2020
  • A leader-follower robot system using low cost small mobile robots has been developed. Sine the developed mobile robot is made of widely used low cost parts, it can be built easily and fastly. Characteristics of the developed sensor array composed of seven low-cost infrared(IR) distance sensors has been investigated, and a positioning algorithm of the reader robot is proposed. Through a series of experiments, it has been verified that the proposed algorithm can detect the position of the reader robot well.

Adaptive Target Detection Algorithm Using Gray Difference, Similarity and Adjacency (밝기 차, 유사성, 근접성을 이용한 적응적 표적 검출 알고리즘)

  • Lee, Eun-Young;Gu, Eun-Hye;Yoo, Hyun-Jung;Park, Kil-Houm
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38B no.9
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    • pp.736-743
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    • 2013
  • In IRST(infrared search and track) system, the small target detection is very difficult because the IR(infrared) image have various clutter and sensor noise. The noise and clutter similar to the target intensity value produce many false alarms. In this paper. We propose the adaptive detection method which obtains optimal target detection using the image intensity information and the prior information of target. In order to enhance the target, we apply the human visual system. we determine the adaptive threshold value using image intensity and distance measure in target enhancement image. The experimental results indicate that the proposed method can efficiently extract target region in various IR images.

Construction and Measurement of Normal Spectral Emissivity Device using Fourier Transform Infrared Spectrometer (퓨리에 변환 적외선 분광기를 이용한 수직 분광 복사율 측정 장치의 제작과 측정)

  • Jeon, Sang-Ho;Yoo, Nam-Joon;Jo, Jae-Heung;Park, Chul-Woung;Park, Seung-Nam;Lee, Geun-Woo
    • Korean Journal of Optics and Photonics
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    • v.19 no.6
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    • pp.400-407
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    • 2008
  • An Instrument to measure normal spectral emissivity is built using a Fourier Transform-Infrared (FT-IR) spectrometer. The instrument is composed of four main parts, reference blackbody, sample furnace, optics system, and FT-IR spectrometer. Measurement ranges of temperature and wavelength are $200^{\circ}C{\sim}500^{\circ}C$ and $3.5{\mu}m{\sim}20{\mu}m$, respectively. Measured emissivity of the reference blackbody is greater than 0.9993 with combined relative uncertainty less than 0.69%, which can be considered an ideal blackbody. We studied the emissivity of opaque alumina, graphite, anodized aluminum, and steel (IMS 200). It is shown that emissivity increases with the roughness of the steel (IMS 200) surface.