• Journal of Technologic Dentistry
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• v.38 no.3
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• pp.193-199
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• 2016

Purpose: The purpose of this study was to know of photopolymerization effect of self-etch dual-cured resin cement on different transmittance and thickness of zirconia disks. Methods: The two types of transparent and opaque zirconia speciments were prepared. The five speciments of each groups were seperated with 0.5mm and 1.0mm thickness. Degree of conversion(DC) were studied by FT-IR spectroscopy using ATR method before and after irradidaion for 40 sec. Results: The relative DC was showed the higher results of ZS5 as compared with ZS10 (p < 0.05). And OP5 and OP10 were lower results than ZS10 (p < 0.05). Conclusion: The photopolymerization effect of dual-cured resin cement were affected by the transmittance and thickness of zirconia.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.212-216
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• 2007

Predicting microcracking properties of the composite laminates in nonuniform stress conditions was the subject in this paper. The uniform stress field meant the stresses were independent of the width direction. The material was the 954-2A/IM7 laminates containing a central hole. Microcracks initiated at the edge of the hole and propagated into the laminate. Because the tensile stress concentration decreased with distance, the microcracks were arrested before the edge of the laminate. Because carbon fiber composites were opaque, a x-ray method was used to detect the length of the propagating microcracks. The microcracking at the near edge of the hole could be reasonably predicted by considering the local laminate stresses and the microcracking toughness measured in unnotched laminates. However, the date away from the hole did not agree with the predictions. The local microcrack density was always much higher than that predicted by the local laminate stress.

• Proceedings of the KWS Conference
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• 2005.06a
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• pp.43-45
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• 2005

A precise bonding technique, transmission laser bonding using energy transfer, for polymer micro devices is presented. The irradiated IR laser beam passes through the transparent part and absorbed on the opaque part. The absorbed energy is converted to heat and bonding takes place. In order to optimize the bonding quality, the temperature profile on the interface must be obtained. Using optical measurements of the both plates, the absorbed energy can be calculated and heat transfer model was applied for obtaining the transient temperature profile. The transmission laser bonding has a potential in the local precise bonding in MEMS or Lab-on-a-chip.

• The Korean Journal of Pain
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• v.8 no.2
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• pp.374-377
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• 1995

Percutaneous neurolysis of upper thoracic sympathetic ganglion was performed by simultaneously injecting 3 ml of pure alcohol into the $T_2$ and $T_3$ levels after testng with same amount of local anesthetics on the same sites. We experienced poor sympatholytic effect or intercostal neuritis and Horner's Syndrome as the result of complication of thoracic sympathetic ganglion block. In Case 1, in spite of the good testing result, neurolytic block effect was poor. In Case 2, intercostal neuritis occurred, but neuralgia subsided within 3 weeks. In Case 3, Horner's Syndrome occurred for 1 day. To increase the success rate of block and decrease the incidence of complications, good radio-opaque dye appearance and good test block effect should be obtained.

• Journal of Astronomy and Space Sciences
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• v.9 no.1
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• pp.111-119
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• 1992

The IUE archival spectra of VV Cephei were collected to investigate the eclipse nature in the ultraviolet. The temperature of the B star has been determined, as approximately 30000K, based on the flux distributions during egress. Light curves of VV Cephei were reduced from the spectrophotometry of the IUE archival spectra. Three light curves at the center wavelengths of 2350 ${\AA}$, 2550 ${\AA}$ and 2850 ${\AA}$ have been analyzed by the modified Wilson and Devinney light curve program. The radii of the B star and M star were deduced to 0.05 and 0.22 of unit separation, respectively. The UV light curves show an evidence that the light was attenuated by the highly opaque atmosphere of the M star.

• International Journal of Air-Conditioning and Refrigeration
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• v.8 no.2
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• pp.11-22
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• 2000

Holographic interferometric tomography can provide reconstruction of instantaneous three-dimensional gross flow fields. The technique however confronts ill-posed reconstruction problems in practical applications. Experimental data are usually limited in projection and angular scanning when a field is captured instantaneously or under the obstruction of test models and test section enclosures. An algorithm, based on a series expansion method, has been developed to improve the reconstruction under the ill-posed conditions. A three-dimensional natural convection flow around two interacting isothermal cubes is experimentally investigated. The flow can provide a challenging reconstruction problem and lend itself to accurate numerical solution for comparison. The refractive index fields at two horizontal sections of the thermal plume with and without an opaque object are reconstructed at a limited view angle of 80$\circ$. The experimental reconstructions are then compared with those from numerical calculation and thermocouple thermometry. It confirms that the technique is applicable to reconstruction of reasonably complex, three-dimensional flow fields.

• Journal of The Korean Digital Architecture Interior Association
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• v.7 no.2
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• pp.19-24
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• 2007

This study attempts to examine and to analyze the characteristics of transparent materials and its methods to apply in space. the ability to see through a physical element, whether it is clear glass, sandblasted acrylic, or a delicate fabric, can have a dramatic and sensory effect on the overall perception of a space. The various range of Transparent materials and product in glass, plastic, fabric, and grid now gives us the potential to maximize the flow of light in our enclosed space. This research will explore how transparent, translucent, and semi-opaque elements can be used within the interior with full range of see-through materials. The transparent materials can be divided in two level - as structural elements and as stylish accessories. A glass partition or floor, metal mesh stairs can create divisions or link one space to another while maintaining effective levels of natural light. there is also various level of products from glass chair to basin. With the enthusiasm for using transparent materials, transparent materials will be more decorative and powerful application while still maximize the highest possible flow of light.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.339-341
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• 2009

A transparent plasma display was developed using transparent glass barrier ribs. Glass barrier ribs were fabricated via a wet etching process. Glass barrier ribs created using a top and bottom etching process showed better transparency compared to those created through only a top etching process. A see-through phosphor layer was obtained by coating the sidewall of the barrier ribs with a conventional opaque phosphor. A fabricated prototype of a transparent plasma display was clear enough to see the background beyond the panel and was well operated by a conventional driving scheme. The maximum luminance was 1150 cd/$m^2$ and the maximum luminous efficacy was 1.35 lm/W in a Ne+13.5%Xe gas-mixture and green cells.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.877-878
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• 2009

To realize the flexible audible display (FAD), polymer dispersed liquid crystal(PDLC) is deposited on PVDF(Poly-vinylidene fluoride) film with piezoelectric property. With applied audio signal, it makes sound more than 70 dB in 700 Hz-10kHz. In case of transparency it is opaque and transmittance is less than 10% at 550nm wavelength without bias voltage. It is turned to be transparent and show transmittance of 66% with driving voltage of 60V.

• KIEAE Journal
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• v.9 no.5
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• pp.39-46
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• 2009

Most Plastic Green Houses in Korea are made according the European weather condition, which lead to have very low solar energy efficiency. Moreover, the function of green houses, as well as the structure of them, has not changed for Korean weather condition. Therefore, the structure and function of them should adopt the regional weather condition in order to improve the energy efficiency. This paper investigates the current plastic green housesin Korea, and presents an alternative for improving the energy efficiency. The elements of green houses were investigated. When using a partial opaque insulation with a thermal storage body, the difference of indoor air temperature became 20C during daytime, and 5C during night, which will save massive fossil fuels.