• Journal of Korean Ophthalmic Optics Society
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• v.10 no.4
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• pp.267-272
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• 2005

We deposited thin films of organic light-emitting-material $Alq_3$(alumina quinoline) on silicon and slide-glass substrates using thermal evaporation method, and measured spectra of ellipsometry angles ${\Delta}$ and ${\Psi}$ in the photon-energy range of 1.5~5.0 eV using a variable angle spectroscopic ellipsometer. The optical constants, refractive index and extinction coefficient, of $Alq_3$ were determined via the dispersion parameters extracted from the curve-fitting process based on Jellison-Modine dispersion function. The reliability of determined optical constants were verified through the comparison of measured and simulated transmittance curves and the good agreement between simulated absorption-coefficient curves and absorbance spectra measured using a spectrophotometer.

• Journal of Korean Society of Transportation
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• v.33 no.3
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• pp.294-303
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• 2015

This paper describes a method that can be used for estimating future carbon emissions and environmental effects. To forecast future land use and transportation changes under various low carbon policies, a DELTA and OmniTRANS combination (a land use-transport integrated model) was applied. Appropriate emission estimation methods and dispersion models were selected and applied in the method. It was designed that the estimated emissions from land use and transportation activity as well as the estimated concentrations of air pollutants and comprehensive air quality index (CAI) are presented on a GIS-based map. The prototype was developed for the city of Suwon and the outcome examples were presented in this paper; it demonstrates what kinds of analysis results are presented in this method. It is expected that the developed method will be very useful for decision makers who want to know the effect of environmental policies in cities.

• Journal of Welding and Joining
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• v.18 no.1
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• pp.59-69
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• 2000

The purpose of the present study was to investigate weld metallurgical phenomena such as primary solidification mode, microstructural evolution and hot cracking susceptibility in nitrogen-bearing austenitic stainless steel GTA welds. Eight experimental heats varying nitrogen content from 0.007 to 0.23 wt.% were used in this study. Autogenous GTA welding was performed on weld coupons and the primary solidification mode and their microstructural characteristics were investigated from the fusion welds. Varestraint test was employed to evaluate the solidification cracking susceptibility of the heats and TCL(Total Crack Length) was used as cracking susceptibility index. The solidification mode shifted from primary ferrite to primary austenite with an increase in nitrogen content. Retained delta ferrite exhibited a variety of morphology as nitrogen content varied. The weld fusion zone exhibited duplex structure(austenite+ferrite) at nitrogen contents less than 0.10 wt.% but fully austenitic structure at nitrogen contents more than 0.20 wt.%. The weld fusion zone in alloys with about 0.15 wt.% nitrogen experienced primary austenite + primary ferrite solidification (mode AF) and contained delta ferrite less than 1% at room temperature. Regarding to solidification cracking susceptibility, the welds with fully austenitic structure exhibited high cracking susceptibility while those with duplex structure low susceptibility. The cracking susceptibility increased slowly with an increase in nitrogen content up to 0.20 wt.% but sharply as nitrogen content exceeded 0.20 wt.%, which was attributed to solidification mode shift fro primary ferrite to primary austenite single phase solidification.

• Electrical & Electronic Materials
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• v.10 no.5
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• pp.467-472
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• 1997

In this study, we investigated the thickness dependence of thermal bleaching(TB) effect as well as photo-induced scalar phenomena, such as photodrakening(PD) effect and photorefraction(PR) change, in chalcogenide A $s_{40}$ G $e_{10}$S $e_{15}$ $S_{35}$ thin films. We found that when these films were exposed for 15 minutes using blue-pass filtered Hg lamp(~4300$\AA$) after annealing for 30 minutes around the glass transition temperature Tg(20$0^{\circ}C$), the refractive index change ($\Delta$n) was varied up to 0.02~0.46 according to each thickness condition and the optical energy gap ($\Delta$ $E_{op}$ ) was shifted to a longer wavelength of approximately 0.67eV, especially for 1000$\AA$-thickness. Also, the TB PD effects have been understood by the results related to optical absorption characteristics. The TB effect could be estimated as increasing the stabilization of amorphous chalcogenide films since absorption slope of extended regions(U) was not changed by annealing. On the other hand, the PD effect could be understood as due to the enhancement of disorder since U and the slope of Urbachs tail(1/F) around an absorption edge were decreased by exposing.ing.n edge were decreased by exposing.

• Polymer(Korea)
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• v.34 no.6
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• pp.579-587
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• 2010

To investigate the properties of PET films, PET films were extruded at various temperature above $T_m$ and quenched at $18^{\circ}C$ for amorphous sheet, and stretched along a direction defined as the machine direction (MD) with a transverse direction (TD) above $T_g$ at various stretching ratios and then annealed at various temperatures produced by SKC PET line. Thermal shrinkage of MD and TD increased with decreasing annealing temperature and extruding temperature, and increasing stretching ratio. The degree of crystallinity, density, heat of fusion (${\Delta}H$) and pre-melting point ($T_m'$) increased with increasing annealing temperature and extruding temperature. Number average molecular weight ($M_n$) and intrinsic viscosity decreased with increasing extruding temperature. Tensile strength and modulus increased with increasing stretching ratio, however decreased with increasing annealing temperature. Reflective index of both stretching and thickness direction increased with increasing stretching ratio and annealing temperature.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.3
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• pp.77-81
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• 2007

We sputtered $TiN_x$ (titanium nitride) thin films on silicon substrates using ultra high vacuum RF magnetron sputtering method, and measured spectra of ellipsometry angles ${\Delta}$ and ${\Psi}$ in the photon-energy range of 1.5-5.0 eV using a variable angle spectroscopic ellipsometer. The optical constants, refractive index and extinction coefficient of the $TiN_x$ films were determined via the dispersion parameters extracted from the curve-fitting process based on Drude+Lorentz oscillator dispersion function. The reliability of determined optical constants were verified through the comparison of between simulated reflectance and reflectance spectra measured using a spectrophotometer.

• Microbiology and Biotechnology Letters
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• v.44 no.1
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• pp.84-88
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• 2016

In this study, bacterial diversity in the living room and bathroom of a residential environment was analyzed using the pyrosequencing method. There was no difference in the diversity index of bacteria between the 2 rooms; however, differences were noted in the composition of bacteria. The classes ${\beta}$-Proteobacteria and ${\delta}$-Proteobacteria were found in the bathroom at higher abundances than in the living room. The phyla Acidobacteria, Chlorobi, Chloroflexi, Fusobacteria, Nitrospirae, and Planctomycetes were found in the bathroom, but not in the living room, indicating a broader range of bacteria. However, the living room showed a more diverse range of bacterial genera than the bathroom did. In both the living room and the bathroom, the genus Methylobacterium was dominant.

• The KIPS Transactions:PartB
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• v.9B no.1
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• pp.29-34
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• 2002

Fingerprint recognition technology was studied by classification and matching. In general, there are five different classifications left loop, right loop, whore, arch, and tented-arch. These classifications are used to determine which class an individual's fingerprint belong to, thereby identifying the individual's fingerprint pattern. The result of this classification, which is sent to the large fingerprint database as an index, helps reduce the matching time and enhance the accuracy of fingerprint matching. The existing fingerprint classification method relies on the number and location of cores and delta points called singular points. The drawback of this method is the lack of accuracy stemming from the classification difficulty involving unclear and/or partially-erased fingerprints. The current paper presents an efficient classification method to rectify the problem associated with identifying Singular points from unclear fingerprints. This method, which is based on Gabor filter's unique characteristics for magnifying directional patterns and frequency range selections, improves fingerprint classification accuracy significantly. In this paper, this method is described and its test result is presented for verification.

• Korean Journal of Optics and Photonics
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• v.20 no.3
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• pp.148-155
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• 2009

In this paper, we analysed what effect the design variables, such as refractive index, central thickness and radius of curvature, had on the first order properties and image quality of optical systems when temperature changed. The optical parameters were varied at each temperature, then the coupling and ruler methods were used to design an athermalized lens for a phone camera. This concept was first used to design the lens for a 1/3.2" 5M phone camera. The designed lens satisfies all the specifications for a phone camera, and the variations of the back focal length(${\Delta}BFL$) are reduced to $10{\mu}m$ for a temperature range of $-10^{\circ}C$ to $+60^{\circ}C$. Also, the TTL of 5.5 mm results in a compact system. All design concepts and results discussed in this paper are expected to be useful in development for the phone and CCTV camera.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.9
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• pp.1355-1360
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• 2008

Effects of dietary ${\delta}$-aminolevulinic acid (ALA) supplementation on serum iron status, blood characteristics, egg production and quality were examined in laying hens in an 8-week feeding trail. Two hundred and forty (Hy-line brown, 40-week-old) layers were randomly assigned to four dietary treatments with ten replications (six layers in adjacent three cages). Dietary treatments included: 1) CON (basal diet), 2) ALA1 (CON+ALA 5 ppm), 3) ALA2 (CON+ALA 10 ppm) and 4) ALA3 (CON+ALA 15 ppm). All nutrient levels of diets were formulated to meet or exceed NRC (1994) recommendations for laying hens. During the entire experimental period, differences of serum iron concentration and total iron binding capacity (TIBC) were significantly increased in ALA1 supplemented treatment (quadratic effect, p<0.05). The difference of total protein between 8 and 0 weeks was significantly higher in ALA2 treatment than CON treatment (quadratic effect, p<0.05). No significant effects were observed on hemoglobin, WBC, RBC, lymphocyte and albumin concentrations. Egg production and egg weight were not influenced by the ALA supplementation. Egg yolk index was also significantly higher in ALA3 treatment than CON treatment at the end of 4 and 8 weeks (linear effect, p<0.05). Haugh unit was increased in ALA3 treatment compared to CON and ALA1 treatments at the end of 8 weeks (linear effect, p<0.05). However, egg shell thickness, breaking strength and yolk color unit were not affected by the ALA supplementation. In conclusion, dietary ALA supplementation at a level of 5 ppm can affect iron concentration in serum while higher levels (10 or 15 ppm) have some beneficial influences on blood profiles and egg quality.