• Korean Chemical Engineering Research
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• v.45 no.6
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• pp.596-603
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• 2007

Rapid or on-line coal analysis is of great interest in coal industry as it would allow efficient plant operation. Multivariate analysis has been applied to near-infrared(NIR) spectra coal for investigating the relationship between coal properties(%) (moisture, ash, volatile matter, fixed carbon, carbon, hydrogen, nitrogen, oxygen, sulfur), heating value(kcal/kg) and corresponding near-infrared spectral data. The quantitative analysis was carried out by applying PLS(partial least squares regression) to determine a methodology able to establish a relationship between coal properties and NIR spectral data being applied mathematical pre-treatments for minimizing the physical features of the samples. As a results of the analysis, this technique is able to classify the species of coals and to predict the all coal properties except ash, nitrogen and sulfur. The efficient operation of coal fired power plant is expected owing to real time on-line coal analysis of moisture and heating value.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.4121-4124
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• 2015

Near infrared blocking function in energy saving window glass is required. The design, deposition and characteristics of optical thin films for reflection of near-infrared light were studied. The optical thin film is designed as laminated film structure with low refractive index film and high index film. Deposition experiments of $SiO_2$ and $TiO_2$ thin films with designed structure using the RF sputtering method were carried out. The characteristics of the thin film with deposition conditions were analyzed. High-refractive-index thin film of $TiO_2$/low refractive-index thin film of $SiO_2$ and high-refractive-index thin film of $TiO_2$ structure for reflection of near-infrared light was designed to be simulated. Results of simulation showed reflectance of 30% or more in the range from 930nm to 1682nm. Triple layer thin films fabricated with simulated results showed wavelength bands from 930nm to 1525nm for the reflectance of 33% or more.

• Journal of Space Technology and Applications
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• v.3 no.2
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• pp.154-164
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• 2023

In space exploration, spectroscopic observation is useful for understanding objects' composition and physical properties. There are various methods for analyzing spectral data, and there are differences depending on the object and the wavelength. This paper introduces a method for analyzing visible & nearinfrared (VNIR) spectral data, which is mainly applied in lunar exploration. The main analysis methods include false color ratio image processing, reflectance pattern analysis, integrated band depth (IBD) processing, and continuum removal as preprocessing before analysis. These spectroscopic analysis methods help to understand the mineral properties of the lunar surface in the VNIR region and can be applied to other celestial bodies such as Mars.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.6
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• pp.1353-1362
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• 2023

Various methods are being attempted to resolve the inconvenience of blood glucose meters used to check blood sugar levels. In this paper, we attempted to estimate blood sugar levels non-invasively using machine learning technology from spectral data acquired using a near-infrared sensor. The non-invasive blood glucose meter used in the study has a total of six near-infrared ray emitters, including visible rays, and a light receiver that receives them. It is a device created to collect spectral data on specific parts of the human body, such as the fingers. To verify whether there was a significant difference depending on blood sugar level, we attempted to estimate blood sugar level through machine learning algorithms. As a result of applying five machine learning algorithm techniques to the collected data and adjusting various hyper parameters, it was confirmed that the support vector regression algorithm showed the best performance.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.86.1-86.1
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• 2017

오리온 성운은 지구와 매우 가까이에 있고, 무거운 별이 포함된 성단과 성운이 밀접하게 연관되어 있어, 오리온 성운 성단은 가장 많이 연구된 천체 중 하나이다. 1993년 HST를 이용한 오리온 성운 성단의 관측으로 나이가 어린별을 둘러싼 물질의 실루엣을 처음으로 보았다. 이후 이러한 천체를 원시행성계원반(protoplanetary disk, Proplyd)이라 불렀으며, 그 형태와 구조, 물리적 과정에 대해 꾸준히 연구가 진행되고 있다. 이 연구에서는 지상관측에서 얻은 UBVI 및 Ha 측광 자료와 원시행성계원반을 상호 동정하고, 원시행성계원반의 형태학적 특징과 측광인자의 관련성을 조사하였다. 또한 Spitzer 중적외선 자료와 Natta et al.(2004)의 근적외선 자료를 통합하여, 현재 사용되고 있는 자외선 초과와 근적외선 방출선을 이용한 질량 강착률 등의 해석에서 주의해야 할 천체들이 있다는 것을 발견했다.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.1021-1024
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• 2008

Near infrared heating as an alternative to the conventional heating techniques for thermography -NDT is tried in this paper. A concrete specimen containing a defect was heated by the near infrared ray and the thermography-NDT technique was applied. Using a dimensinless temperature, the defects were detected. It was found that the near infrared ray could efficiently heat up the concrete specimen compared to others conventional methods like lamps, heat flow, etc.

• Journal of Broadcast Engineering
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• v.26 no.1
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• pp.88-98
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• 2021

Recently, the crime prevention and culprit identification even in a low illuminated environment by CCTV is becoming ever more important. In a low lighting situation, CCTV applications capture images under infrared lighting since it is unobtrusive to human eye. Although the infrared lighting leads to advantage of capturing an image with abundant fine texture information, it is hard to capture the color information which is very essential in identifying certain objects or persons in CCTV images. In this paper, we propose a method to acquire color information through DCGAN from an image captured by CCTV in a low lighting environment with infrared lighting and a method to remove color noise in the acquired color image.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.526-531
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• 2010

For efficient use of wood, it is important to control moisture of wood in processing wood. Near-infrared (NIR) spectroscopy can be used to estimate the physical and chemical properties of materials quickly and nondestructively. In this study, it was intended to measure the moisture contents on the surface of wood using NIR spectroscopy coupled with multivariate analytic statistical techniques. Because NIR spectroscopy is affected by the chemical components of the specimens and contains signal noise, a regression model for detecting moisture content of wood was established after carrying out several numerical pretreatments such as Smoothing, Derivative and Normalization in this study. It shows that the regression model using NIR absorbance in the range of 750~2,500 nm predicts the actual surface moisture content very well. Near-infrared spectroscopy technique developed in this study is expected to improve a technology to control moisture content of wood in using and drying process.

• Journal of Korean Physical Therapy Science
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• v.2 no.4
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• pp.771-778
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• 1995

The purpose of this study was to determine the effects of linear polarized near-infrared ray radiation on experimental pain threshold in healthy adult subjects. Thirty healthy adult subjects were divided into 5 groups: 1) group 1, super lizer radiation at 0 % ; 2) group 2, super lizer radiation at 10 % ; 3) group 3, super lizer radiation at 20 % ; 4) group 4, super lizer radiation at 40 % ; 5) group 5, super lizer radiation at 80 %. The polarized near-infrared ray radiation was applied on LI 4 point of subject's right hand at a fixed time for 30 second. Experimental pain threshold were measured with electrical current on the right hand at 5 intervals for each radiation: 1) pretreat; 2) posttreat ; 3) posttreat of 1/2 hr ; 4) posttreat of 1 hr ; and 5) posttreat of 2 hrs. Data were analyzed using analyses of variance with repeated measures for pain threshold. No significant interaction between power output and time for pain threshold was found. Significant effects of power output and time for experimental pain threshold were found. Significant increase was noted in experimental pain threshold in group 4 and group 5 at posttreat, posttreat of 1/2, 1 hr and 2 hrs as a result of the applications of the polarized near-infrared ray radiation. This study indicate that polarized near-infrared ray radiation with above 40 % of power output increases pain threshold, thus possibly increasing options in choosing radiation output for treating pateint with pain. Further study is needed to compare the effects of these radiation in patients with clinical pain.

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.1
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• pp.21-30
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• 2021

The purpose of this study is to investigate the antibacterial effects of indocyanine green (ICG) and near-infrared diode lasers on multispecies biofilms. Multispecies biofilms of Streptococcus mutans, Lactobacillus casei and Candida albicans were treated with different irradiation time using photosensitizer ICG and 808 nm near-infrared diode laser. Colony forming unit (CFU) was measured, and qualitative evaluation of biofilm was performed with confocal laser scanning microscopy (CLSM). Temperature measurement was conducted to evaluate photothermal effect. In the groups using ICG and diode laser, reduction in CFU was statistically significant, but the difference in antibacterial effect on L. casei and C. albicans with irradiation time was not significant, and similar results were confirmed with CLSM. Groups with ICG and diode laser showed higher temperature elevation than groups without ICG, and results of measured temperature were similar to the range of hyperthermia. In conclusion, ICG and near-infrared diode laser showed antibacterial effects on multispecies biofilms, but studies on protocol are necessary for clinical application.