• 비파괴검사학회지
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• 제37권2호
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• pp.91-98
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• 2017

Recently, composite materials have been mainly used in the main wings, ailerons, and fuselages of aircraft and rotor blades of helicopters. Composite materials used in rapid moving structures are subject to impact by hail, lightning, and bird strike. Such an impact can destroy fiber tissues in the composite materials as well as deform the composite materials, resulting in various problems such as weakened rigidity of the composite structure and penetration of water into tiny cracks. In this study, experiments were conducted using a 2 kW halogen lamp which is most frequently used as a light source, a 2 kW near-infrared lamp, which is used for heating to a high temperature, and a 6 kW xenon flash lamp which emits a large amount of energy for a moment. CFRP composite sandwich panels using Nomex honeycomb core were used as the specimens. Experiments were carried out under impact damages of 1, 4 and 8 J. It was found that the detection of defects was fast when the xenon flash lamp was used. The detection of damaged regions was excellent when the halogen lamp was used. Furthermore, the near-infrared lamp is an effective technology for showing the surface of a test object.

• 한국정보전자통신기술학회논문지
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• 제3권4호
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• pp.16-22
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• 2010

본 연구에서는 분광광도계 시스템에서 700-1,100 nm 근적외선 대역의 조명 영향평가에 대한 연구를 수행하였다. 분광광도계는 분자영상 의학 분야 및 의료용 장비에 다양하게 사용되고 있다. 근적외선 대역에서의 조명 영향평가를 알아보기 위하여 본 연구에서 사용한 색상지는 표준반사물질 및 만셀 표준 색상인 빨강, 노랑, 초록, 파랑 색상지를 사용하였다. 분광광도계 시스템의 근적외선 대역을 비교 분석하기 위하여 실험 재료 색상지를 색상지별 20번 측정하였고, 조명은 백열등, 형광등, 인버터 형광등 및 조명 조합으로 실험하였다. 백열등, 형광등, 인버터 형광등의 단일 조명에서는 백열등에서 가장 높은 분광반사율 반응을 보였고, 조명들의 조합에서도 백열등이 포함된 조명 조합이 높은 분광반사율을 보였다. 따라서 분광광도계의 근적외선 대역을 이용하여 분광광도시스템을 구축한다면, 분광반사율이 높은 백열등을 적용하는 것이 좋은 것으로 판단되었다.

• 한국태양에너지학회 논문집
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• 제24권1호
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• pp.21-27
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• 2004

Near Infrared Ray (NIR) are primarily of interest to the high energy physicist. It is the intermediate portion of the spectrum, which extends from approximately 0.8 to 1.5 ${\mu}m$ and include a portion of the all of infrared, that is thermal radiation and is pertinent to heat transfer. It is important to study that temperature distribution of the drying materials by surface encompasses a range of NIR wave lengths. This study is to investigate the characteristics of NIR dryer by experimental results. it was made a comparison with various textiles, velocity ratio and distance of lamp and textiles. In case of spongy type textile the drying performance is the superior of all. The 0.15m distance drying effect of improvement 30% more than 0.26m distance between lamp and textiles. As the contained water increases, the drying speed for textile can be increased.

• 한국공작기계학회논문집
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• 제15권5호
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• pp.1-6
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• 2006

The purpose of this study is to develop to portable near infrared analyzer measuring the sugar content of the fruits on a tree before harvesting ones. The portable near infrared system consists of a tungsten lamp, a coaxial optical fiber bundle and a multi-channel detector, which has 256 pixels and a concave transmission grating. Reflectance NIR spectra of orange were recorded by using a coaxial optical fiber bundle. The spectra were collected over the spectral range $400{\sim}1100nm$. Partial least squares regression(PLSR) was applied for a calibration and validation for determination of sugar contents. The multiple correlation coefficient was 0.99 and standard errors of calibration(SEC) was 0.069 brix. The calibration model predicted the sugar content for validation set with standard errors of prediction(SEP) of 0.092 brix. The sugar content in fruits was successfully quantified using the portable near infrared analyzer.

• Rapid Communication in Photoscience
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• 제4권2호
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• pp.34-36
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• 2015

New spectroscopic characteristics of amorphous ferric hydroxide ($Fe(OH)_3$), interestingly in the near infrared (NIR) region, are presented in this study. The absorption spectrum of ferric hydroxide covers wide spectral regions from ultraviolet to NIR (200~900 nm). Unique emission bands were newly observed in the NIR regions (800~1400 nm). Several bands of this NIR emission are quiet well overlapped with the combinational vibrational absorption bands of water. From photothermal conversion study, very interestingly, temperature of aqueous mixture solution including the amorphous ferric hydroxide was significantly increased from ambient temperature to $38^{\circ}C$ for 30 minutes under irradiation of a standard helium lamp.

• 약학회지
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• 제46권5호
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• pp.331-336
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• 2002

The purpose of this study is to develop a non-invasive blood glucose measurement method by a portable near infrared (NIR) system which was newly integrated by our lab. The portable NIR system includes a tungsten halogen lamp, a specialized reflectance fiber optic probe and a photo diode array type InGaAs detector; which was developed by a microchip technology based on the lithography. Reflectance NIR spectra of different parts of human body (finger tip, earlobe, and inner lip) were recorded by using a fiber optic probe. The spectra were collected over the spectral range 1100 ∼ 1740 nm. Partial least squares regression (PLSR) was applied for the calibration and validation for the determination of blood glucose. The calibration model from earlobe spectra presented better results, showing good correlation with a glucose oxidase method which is a mostly used standard method. This model predicted the glucose concentration for validation set with a SEP of 33 mg/dL. This study indicated the feasibility for non-invasive monitoring of blood glucose by a portable near infrared system.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1123-1123
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• 2001

In recent years, a miniature spectrometer has been extensively developed due to the marriage of fiber optics and semiconductor detector array. This type of miniature spectrometer has advantages of low price and robustness due to the capability of mass production and no moving parts are required such as lenses, mirrors and scanning monochromator. These systems are ideal for use in teaching labs, process monitoring and field analyses. A portable near infrared (NIR) system has been developed for qualitative and quantitative analysis. This system includes a tungsten halogen lamp for light source, a fiber optics connected a light source, and a sample module to the microspectrometer, The size of spectrometer can be as small as 2.5 cm x 1.5 cm x 0.1 cm. Wavelength ranges can be chosen as 360-800 nm, 800-1100 nm and 1100-1900 nm depending on the type of detector. The software consists of various tools for multivariate analysis and pattern recognition techniques. To evaluate the system, long and short-term stability, wavelength accuracy, and stray light have been investigated and compared with conventional scanning type NIR spectrometer. This developed system can be sufficiently used for quantitative and qualitative analysis for various samples such as agricultural product, herbal medicine, food, petroleum, and pharmaceuticals, etc.

• 설비공학논문집
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• 제25권5호
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• pp.289-296
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• 2013

A near infrared (NIR) heating system has advantages over the conventional convection-based systems, in terms of heating uniformity and energy efficiency. When it is over-heated during its operation, the radiation lamp gets blackened, and the life of the radiation module becomes severely limited. The heat transfer system in the module is based on a high operating-temperature, and the radiation makes it difficult to analyze in detail the reliability issue, with an experimental approach alone. We developed a numerical heat-transfer model of the NIR heating system. We applied a ray-tracing method on the radiative heat transport, and a finite volume method on the conductive and convective systems, respectively. The cooling performance of the system is presented, based on the energy and flow distributions in the module. The factors that directly affect the module life are analyzed, such as the surface temperatures of the lamp glass and the reflector, and design improvements are discussed.

• Journal of Microbiology and Biotechnology
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• 제21권12호
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• pp.1306-1311
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• 2011

Recombinant Rhodopseudomonas palustris, harboring the carotenoid-metabolizing gene crtI (CrtIBS), and whose color changes from greenish yellow to red in response to inorganic As(III), was cultured in transparent microplate wells illuminated with a light emitting diode (LED) array. The cells were seen to grow better under near-infrared light, when compared with cells illuminated with blue or green LEDs. The absorbance ratio of 525 to 425 nm after cultivation for 24 h, which reflects red carotenoid accumulation, increased with an increase in As(III) concentrations. The detection limit of cultures illuminated with near-infrared LED was 5 ${\mu}g$/l, which was equivalent to that of cultures in test tubes illuminated with an incandescent lamp. A near-infrared LED array, in combination with a microplate, enabled the simultaneous handling of multiple cultures, including CrtIBS and a control strain, for normalization by the illumination of those with equal photon flux densities. Thus, the introduction of a near-infrared LED array to the assay is advantageous for the monitoring of arsenic in natural water samples that may contain a number of unknown factors and, therefore, need normalization of the reporter event.

• Design & Manufacturing
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• 제11권1호
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• pp.7-13
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• 2017

The aim of this study is to develop the dies oven for energy-saving during the pre-heated process of extrusion dies. Applying high-efficiency near-infrared heater, single cell type dies oven was developed as a substitute for traditional chest type oven. Therefore the dies is individually heated uniformly to operation temperature so rapidly. By using the developed dies oven, electric-energy consumption of preheating extrusion dies reduced up to 30% and the waiting time in the oven also minimized up to 90min. In addition, the results have shown that it is possible to accurately control the dies temperature for improving the quality of extruded profile and to minimize die bearing oxidation and nitride layer degradation responsible for surface defects on the profile and shorter die life.