• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.4
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• pp.34-40
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• 2004

In this paper, we have studied the OCT(Optical Coherence Tomography) system which has been advantages of high resolution, 2-D cross-sectional images, low cost and small size configuration. The characteristics of light source determine the resolution and coherence length. The light source has a commercial SLD with a central wavelength of 1,285 ill11, 35.3 nm(FWHM). The optical delay line is necessary to make equal with the optical path length to scattered light or reflected light from a sample. In order to make equal the optical path length, the stage that is attached to a reference mirror is controled by a step motor. And the interferometer is configured with the Michelson interferometer by using a single mode fiber, and the scanner can be focused on the sample by using a reference ann Also, the 2-dimension cross-sectional images were measured with scanning the transverse direction of the sample by using a step motor. After detecting the internal signal of lateral direction, a scanner is moved to obtain the cross-sectional image of 2-dimension by using step motor. A photodiode, which has high detection sensitivity and excellent noise characteristics has been used. The detected small signal has a noise and interference. After filtering and amplifying the signal, the output signal is demodulated the waveform And then, a cross-sectional image is seen through converting this signal into a digitalized signal by using an AID converter. The resolution of the sample is about 30${\mu}{\textrm}{m}$, which corresponds to the theoretical resolution. Also, the cross-sectional images of onion cells were measured in real time scheme.

• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.1
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• pp.65-75
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• 2022

The aim of this study was to evaluate QLF (quantitative light-induced fluorescence) technology for the caries detection in primary teeth and validate the relationships between the cavity volume of carious lesions and QLF analysis results. Total 125 tooth surfaces include 53 occlusal surfaces, and 72 proximal surfaces were investigated with the portable QLF device for detection of dental caries in primary molars. Micro-CT radiograph was also performed to classify carious lesions and calculate the cavity volume. QLF showed good accuracy and reliability (sensitivity 0.75 - 0.94, specificity 0.82 - 0.95, and AUROC 0.88 - 0.98) for the caries detection in primary teeth except 𝚫R average results of proximal caries which showed relatively low values. Statistically significant relationships were found between 𝚫F average, QS-Index and the cavity volume according to Spearman rank-order correlation coefficients (r = 0.805 - 0.832, p < 0.001). QLF detection method would be a harmless and reliable way for children to diagnose dental caries without the concern about radiation exposure.

• Journal of Photoscience
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• v.9 no.2
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• pp.332-334
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• 2002

We examined the effects of supplementary ultraviolet-B (UV-B) radiation on the changes in synthesis and degradation of ribulose-I, 5-biphosphate carboxylase /oxygenase (Rubisco) and light-harvesting chlorophyll a/b binding protein of PSII (LHCII), as well as mRNA levels for small and large subunits of Rubisco (rbcS and rbcL, respectively) and LHCII (cab) with leaf age in UV-sensitive rice (Norin I) and UV-resistant rice (Sasanishiki). Both Rubisco and LHCII were actively synthesized until the leaf had fully expanded, and then decreased with leaf age. Synthesis of Rubisco, but not LHCII, was significantly suppressed by UV-B in Norin 1. The degradation of Rubisco was enhanced by UV-B around the time of the leaf maturation in the two cultivars. The levels of rbcS and rbcL were reduced by UV-B at the early leaf stages after emergence in both cultivars. The level of cab was first present at the highest level in the two cultivars, but drastically decreased due to UV-B treatment immediately after leaf emergence in Norin 1. It was proved that synthesis and degradation of Rubisco and LHCII greatly changed with leaf age: Rubisco synthesis was significantly suppressed by supplementary UV-B radiation at the transcription step during the early leaf stages. It was also suggested that the difference between the two rice cultivars in sensitivity to UV-B in the synthesis of Rubisco might be due to the specific suppression not only after transcription but also at transcription.

• Journal of Sensor Science and Technology
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• v.15 no.3
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• pp.192-198
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• 2006

In this study, the light addressable potentiometric sensors (LAPS) with $Si_{3}N_{4}/SiO_{2}/Si$, and $Ta_{2}O_{5}/SiO_{2}/Si$ structures were fabricated. The penicillinsae was immobilized on the devices to hydrolyze the penicillin using self-assembled monolayer (SAM) method. Then response characteristics according to the penicillin concentrations were measured and compared. The measuring system was simplified by using LabVIEW. The pH response characteristics of fabricated devices are 56 mV/pH ($Si_{3}N_{4}$ sensing membrane) and 61 mV/pH ($Ta_{2}O_{5}$ sensing membrane). The sensitivity of sensor by enzyme reaction result of the enzyme reaction were 60 mV/decade and 74 mV/decade for $Si_{3}N_{4}/SiO_{2}/Si$ and $Ta_{2}O_{5}/SiO_{2}/Si$ structure, respectively, in the range of $0.1\;mM{\sim}10\;mM $of the penicillin concentration.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.21-25
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• 1997

Application of the color indicators to kimchi packages was investigated in order to monitor the ripeness of commercial kimchi products during storage and distribution. Kimchi was packed in polypropylene (PP) tray and nylon/cast polypropylene (Ny/CPP) lid where the indicating sachet consisting of $CO_2$ absorbent and chemical dye (bromocresol purple and methyl red) was attached. The ripeness of kimchi during storage at $0{\sim}20^{\circ}C$ was measured in terms of pH and titratable acidity (TA), which were compared with Hunter color values of the indicators. The color of bromocresol purple dye turned from light blue to purple, while that of methyl red turned from light yellow to red. Regardless of the storage temperatures, Hunter b values of bromocresol purple type and Hunter a values of methyl red type appeared to be proportional to both the pH and TA values of kimchi. These results suggest that the color indicators be employed as one of the effective techniques for sensing the ripeness of packaged kimchi products without destructing the package.

• Analytical Science and Technology
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• v.30 no.2
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• pp.75-81
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• 2017

5-methylthioninhydrin (5-MTN) is an amino acid sensitive reagent used for the development of latent fingermarks deposited on porous surfaces such as paper and wood. The present study demonstrates that the 5-MTN can be used as a latent footwear impression enhancement reagent, by reacting with trace multivalent metal ions, which are the main components of the latent footwear impression. 5-MTN and L-alanine complex (MTN-ALA) used for the latent footwear impression development was prepared, by mixing $4.5{\times}10^{-3}M$ 5-MTN (in methanol) and $4.5{\times}10^{-3}M$ L-alanine (in methanol) in 1:1 ratio, and keeping undisturbed at room temperature for 24 h. The latent footwear impressions were deposited on white and black non-porous surfaces (glass plate, polyethylene panel, polypropylene panel, acryl panel, polyvinyl chloride (PVC) panel, poly(methyl methacrylate) (PMMA) panel, acrylonitrile-butadiene-styrene (ABS) panel, tile), and a semi-porous surfaces (painted wood). The latent footwear impressions on these surfaces were treated with MTN-ALA complex by spraying. The fluorescence of footwear impressions (occurred due to the reaction between MTN-ALA and metal complexes) was observed under a 505 nm forensic light source and an orange barrier filter. The enhancement of latent footwear impression was achieved from black surfaces without any blurring. However, the fluorescence (enhancement) of footwear impression was not observed on the white PVC, PMMA, and ABS surfaces, because the incident light interfered and reflected on the surface. The sensitivity of MTN-ALA was superior to 2,2'-dipyridil, which is a representative non-fluorescing footwear impression enhancement reagent, and similar to 8-hydroxyquinoline, which is a representative fluorescing footwear impression enhancement reagent.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.1
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• pp.13-18
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• 2000

In this paper, we use the C light which is a daylight and consider the incident beam having the Gaussian amplitude. We investigated the illuminance distributions and the variation in chromaticity of optical system having the truncated Gaussian amplitude on the focal plane and along the optical axis using the C light source. We also use the three sensitivity functions of human eye(CIE 1931) for wavelengths which are from 380nm to 780nm. When the truncation grade of incident beam having Gaussian amplitude decreases, the size of central spot on the focal plane and the depth of focus along the optical axis decrease, and the variation in chromaticity on the focal plane and along the axis increases rapidly. As the illuminance on the focal plane decreases the variation in chromaticity of optical system increases rapidly, and as the depth of focus increases the variation in chromaticity of optical system decreases.

• Journal of Digital Convergence
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• v.11 no.4
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• pp.229-234
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• 2013

The purpose of this study is to develop a lighting apparatus of the illuminance and color temperature to maximize the ability of the optimal combination of light sources that can be controlled efficiently control device. Finding people comfortable feeling for indoor lighting that can be used in a variety of color temperature illumination area by combining light sensitivity can be realized. Lighting apparatus for fluorescent lamps with different color temperature of 2000K and 8000K, and by varying the quantity of each of the fluorescent lamps, the illuminance of lighting equipment and color temperature through optical simulations were evaluated. By infrared remote control receiver, divided into 5 types of relaxation, conversation, meeting, hospitality, arts and the lighting environment you want to transfer the PC0 ~ PC4 through the parallel port on the mode selected by the user at the receiving end the DC voltage output. EEFL inverter input DC voltage and the DC input voltage, depending on the level of EEFL dimming value (illuminance and color temperature) lighting environment you want to create change while using a PIR sensor EEFL automatically turn off if people do not have was developed so that the power consumption so you can save.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.7
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• pp.516-520
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• 2012

In this paper, we have theoretically analyzed and designed a dielectric multi-layer sensor with a SPR (surface plasmon resonance) using analytical calculation and FDTD (finite difference time-domain) methods. The proposed structure is composed of periodic layer and thin metal film. It has many advantages. One of that is a high sensitivity of the SPR. Another is a high Q-factor of the characteristics in the PhC (photonic crystals) micro-cavity structure. The incident light has double resonance characteristics, because the filtered light by PhC structure, dielectric multi-layer, is met the thin metal film for SPR effect. We have also observed the change of resonance characteristics according to the variation of effective index on the metal film.

• Biomedical Science Letters
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• v.2 no.2
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• pp.249-255
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• 1996

In this paper, a in situ hybridization(ISH) has been used to investigate the yield of viral RNA expression from each organ tissues. It is studied to establish a rapidly, specific diagnostic method detecting rabbit haemorrhagic disease virus(RHDV) RNA in 10% formalin-fixed, paraffin-em-bedded tissues of naturally RHDV-infected rabbits using oligonucleotide probe to be made by RHDV total sequences. Biotin was used as the oligonucleotide probe marker. in situ hybridization is detected the virus genome in the cells and tissue as specifically compared with others nucleic acid hybridization method. All ISH procedure of RHDV were completed to Mi-croProbe$^{TM}$ capillary action system within 1-2 hours. In this report, RHDV was distributed widely in the cytoplasm of liver cell and the cortex of kidney but lung tissue and medulla of kidney were showed to positive reaction at locally. Although not entirely free of technical limitations, nucleic acid identification holds advantages over other diagnostic tests, including exquisite sensitivity, specificity, interchangeability and speed. It is expected that, in the immediate future viral nucleic acid detection will be a prominent part of the methods used in histopathology.