• Korean Journal of Optics and Photonics
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• v.5 no.1
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• pp.9-17
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• 1994

Optical properties of $TiO_2$ thin films prepared by ion-beam assisted deposition(1BAD) were investigated. The result shows that the refractive index of IBAD TiOL thin films measured by an envelope method is closer to that of the corresponding bulk than that of conventionally deposited $TiO_2$ thin films and the packing density of IBAD $TiO_2$ thin films measured by a vacuum-to-air spectral shift of films increases drastically. The vacuum-to-air spectral shift of an IBAD $(TiO_2/SiO_2)$ multilayer interference filter was negligible as compared to that of a conventional interference filter and so the IBAD filter is denser and more stable optically than the conventional filter. Also it is observed that the IBAD and conventional $TiO_2$ thin films are stoichiometric and amorphous.

• The Research Journal of the Costume Culture
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• v.13 no.4 s.57
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• pp.540-549
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• 2005

It was the purpose of this study to investigate the effect of chitosan treatment and mordanting on the air-permeability, fastness of the dyestuff to washing, fastness of the dyestuff to light, and antimicrobial effect of cotton and nylon fabrics dyed using Rhusjara ica. In the dyeing experiment, examinations were made on the difference between the chitosan treated fabrics and chitosan untreated fabrics, and on the difference according to the type of mordanting agents and the mordanting methods. Dyeing was carried out for the chitosan treated and untreated fabrics under the conditions of non-mordanting and Al, Sn, Fe mordanting. As a result, due to the dye-uptake of the dyestuff component of the Rhusjara ica, the air-permeability values decreased considerably. And due to the action of the mordanting agents, the air-permeability decreased also. The air-permeability decreased more conspicuously in the case of the dyestuffs uptake to the chitosan components than in the case of the dyestuffs uptake to the cotton fibers or nylon fibers. Nylon dyed fabric exhibited better wash fastness than the cotton dyed fabric. As the number of washing increased, the color of the cotton fabric specimens and nylon fabric specimens, dyed using Rhusjara ica, shifted toward yellowish. The light fastness values were in the range of grade 1${\~}$2, which were very inferior. The light fastness values did not improve according to the mordanting or to the chitosan treatment. In the case of chitosan untreated fabrics dyed using Rhusjara ica, the growth rate of the bacteria promoted, on the contrary, compared to that of the control white fabric.

• Journal of Bio-Environment Control
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• v.27 no.1
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• pp.46-53
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• 2018

This study was conducted to determine which greenhouse provided good environmental conditions for strawberry production, and performed better at conserving energy. Temperature, RH, VPD, $CO_2$, solar radiation, yield, and fuel consumption were the parameters analyzed. The temperatures of both greenhouses were well controlled in order to provide optimal day and night temperatures for strawberry production. The air inflated double layer greenhouse had higher RH values (more than 90% at night), which led to higher disease occurrence, in comparison to the conventional double layer greenhouse. Furthermore, the air inflated double layer greenhouse had lower VPD values than the conventional double layer greenhouse. Therefore, better RH and VPD were observed in the conventional double layer greenhouse. Higher $CO_2$ concentration was observed in the air inflated double layer greenhouse while the conventional double layer greenhouse ventilated better than the air inflated greenhouse, because of its side ventilators. Moreover, higher solar radiation in the conventional double layer greenhouse resulted in higher yield, in comparison to the air inflated double layer greenhouse. Thus, we can conclude that the conventional double layer greenhouse provided a better environment for crop growth, in comparison to the air inflated double layer greenhouse. Regarding fuel consumption, the air inflated double layer greenhouse had lower fuel consumption than the conventional double layer greenhouse. Therefore, from an energy consumption point of view, we can conclude that the air inflated double layer greenhouse performed better than the conventional double layer greenhouse.

• Applied Chemistry for Engineering
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• v.9 no.2
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• pp.214-219
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• 1998

The transparent conducting tin oxide films were deposited on g1ass substrates by the ultrasonic spray pyrolysis. Examined were effects of deposition parameters on the electrical resistance, optical transmittance, crystal structure, and thickness of tin oxide films. As both the deposition time and concentration of tin(IV) chloride increase, the deposited tin oxide films exhibited the decrease of electrical resistance and optical transmittance in the visible and near infrared region. With increasing heat-treatment temperature in air, the deposited tin oxide films showed the enhanced electrical resistance and optical transmittance. This study suggests that the ultrasonic spray pyrolysis may be a promising deposition technique effectively to prepare transparent conducting films of good quality in a single step.

• Food Science and Preservation
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• v.5 no.3
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• pp.207-210
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• 1998

To prolong the shelf life of green chili pepper, packaging films such as 30 $\mu\textrm{m}$ low density polyethylene(LDPE), 20 $\mu\textrm{m}$ perforated polyolefin (SM250), 30 $\mu\textrm{m}$ cast polypropylene (CPP) and 15 $\mu\textrm{m}$ polyolefin (MPD) were used. LDPE showed a suitable gas concentration which consisted of 3-5% O$_2$ and below 5% CO$_2$for keeping quality of green chili peppers after 10 days. Though weight loss was 9.3% for SM250 after 5 days, others showed below 2.0% weight loss after 40 days. Green chili peppers inside CPP package revealed a great decrease in ascorbic acid content after 30 days. SM250 showed a less total microbial count among packages, but there was no great differences among packages.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.484-485
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• 2011

반사방지(Anti-Reflection, AR) 특성은 태양전지, LED, 광검출기 등의 광전소자와 디스플레이의 효율과 투과도를 향상시키기 위해 적용되고 있다. 또한 최근에 네비게이션, 스마트폰의 보급 증가로 인해 소형 디스플레이에 지문방지와 동시에 반사방지 기능을 갖는 필름이 사용되고 있다. 현재 적용되고 있는 반사방지 필름은 다층박막 코팅으로 형성된 필름[1]으로 생산단가와 박막의 내구성 및 신뢰성에 문제점을 가지고 있다. 이런 문제점을 해결하기 위해 나노구조로 제작 되는 반사방지 필름에 관한 연구가 활발히 진행되고 있다[2]. 나노구조로 형성된 반사방지 구조는 moth-eye 구조라고 하며, 기본 원리는 원뿔 형태를 형성된 나노 구조를 통해 공기와 나노구조 사이의 유효 굴절률을 서서히 변화시켜 반사를 줄이는 것이다. 그러므로 moth-eye 나노구조는 파장 이하의 pitch와 파장 크기의 높이를 갖도록 구조가 제작되어야 한다[3]. Photo-lithography[4], e-beam lithography[5], interference lithography[6], dip-pen nanolithography[7], hybrid nano-patterning lithography[8] 등 여러 가지 방법으로 나노 구조를 제작하고 있으나, 네비게이션이나 스마트폰 등에 적용될 수 있는 대면적으로 제작하기 위해서는 roll-to-roll printing과 같은 대면적 공정을 이용하여 제작하는 것이 필요하다. 본 논문에서는 원통형 알루미늄 rod에 양극산화를 통해 다공성 AAO(anode aluminium oxide) template를 제작하고, roll-to-roll printing 기술을 사용하여 moth-eye 나노구조를 갖는 반사방지 필름을 제작하는 것에 대해 기술하였다.

• Membrane Journal
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• v.21 no.1
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• pp.55-61
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• 2011

$BaCo_{0.7}Fe_{0.22}Nb_{0.08}O_{3-{\delta}}$ oxide was synthesized by solid state reaction method. Dense ceramic membrane was prepared using as-prepared powder by pressing and sintering at $1,200^{\circ}C$. XRD result of membrane showed single perovskite structure. Leakage and oxygen permeation test were conducted on the membrane sealed by glass ring as a sealing material. The oxygen permeation flux increased with increasing temperature and pressure difference and maximum oxygen permeation flux was $2.3mL/min{\cdot}cm^2$ at $950^{\circ}C$ with $Po_2$ = 0.63 atm of oxygen partial pressure. The oxygen permeation in the condition of air with $CO_2$ (300 ppm) as feed stream decreased as much as only maximum 2.9% in comparison with air feed stream. It indicated $BaCo_{0.7}Fe_{0.22}Nb_{0.08}O_{3-{\delta}}$ membrane is more stable than another membrane for carbon dioxide.

• Geophysics and Geophysical Exploration
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• v.13 no.1
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• pp.96-101
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• 2010

A pulse radar system has been developed recently to detect dormant underground tunnels that are deeply located at depths of hundreds of metres. To check the ability of the radar system to detect an obliquely oriented tunnel, five different borehole pairs in the tunnel test site were chosen so that the horizontal lines-of-sight cut the tunnel axis obliquely, in $15^{\circ}$ steps. The pulse radar signatures were measured over a depth range of 20 m around the centre of the air-filled tunnel. Three canonical parameters, consisting of the arrival time, attenuation, and dispersion time were extracted from the first and second peaks of the measured radar signatures. Using those parameters, the radar system can detect obliquely oriented tunnels at various angles up to 45 from the transmitter-receiver line of sight.

• Membrane Journal
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• v.20 no.1
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• pp.76-86
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• 2010

This study investigated the effect of 2-butoxyethanol (BE) as a nonsolvent additive, relative humidity and air contact time on the structure formation of microfiltration membranes, permeation and morphology properties in phase inversion process. The membranes were prepared by using polyethersulfone (PES)/Dimethyl formamide (DMF)/p-toluenesulfonic acid (TSA)/Polyvinylpyrrolidone (PVP)/BE casting solution and water coagulant. Casting solutions containing various concentration of BE were exposed to a water vapor, under 60 and 80% of relative humidity for 40 and 90 sec, which would be absorbed on. The correlations between the membrane permeation properties and surface/inner structures of membrane were investigated. The characterization of membranes was carried out by a capillary flow porometer, a FE-SEM and a water permeation test apparatus. The surface structure of PES membranes was affected by the exposure time as well as the relative humidity strongly. Furthermore, the addition of BE helped control surface and inner structure at certain humidity and exposure time.

• The Research Journal of the Costume Culture
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• v.15 no.2 s.67
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• pp.276-283
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• 2007

The purpose of this study were to investigate characteristic changes on nonwoven fabric for disposable work clothes by the yellow soil printing. It separate grind yellow soil as two different size of particles $45\sim52{\mu}m$ and $53\sim65{\mu}m$ for hand screen printing on three kind of nonwoven fabrics. To examine the effect of yellow soil printing on nonwoven fabric were to observe, dyeability by using spectrophotometer, moisture regain by oven method, air permeability, anion property and antibacterial activity. The results were as follows: When yellow soil concentration increased from 5 to 10%, K/S value also increased from 1.05 to 1.88. When yellow soil concentration increased, moisture regain also increased. In same concentration, moisture regain occurred higher as particle of small size. Air permeability decreased when the charcoal printing concentration increased. Anion occurrence appeared $140\sim160ion/cc$ from three different kinds of nonwoven fabrics in 3% and 9% yellow soil concentration. Therefore, occurred anion ineffectively. In concentration of 3%, rate of deodorization measured as 89%, 83% and 87%, and 9% concentration caused 96%, 86% and 93% of high deodorization. Antibacterial activity examination in nonfinished nonwoven fabric resulted range of 60%, however, 3% and 9% concentration finished nonwoven fabric resulted 99.9% of excellent antibacterial activity Surface temperature increased $1.5\sim2^{\circ}C$ by yellow soil finishing.