• Elastomers and Composites
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• 제57권3호
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• pp.114-120
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• 2022

The tensile properties of the extruded PC film were measured in the extrusion direction and perpendicular to the extrusion direction. The measured properties were the elastic modulus and Poisson's ratio at the glass transition temperature of PC. The measured orthotropic properties of the film were used for the computer simulation of vacuum forming. In this simulation, three mold shapes were tested: dome, trapezoid, and cubic, and the vacuum was applied between the mold surface and the heated film. The stress, strain, thickness, and stretch ratio distributions of the film in different mold shapes were observed and compared. The thermoforming simulation method used in this study and the obtained results, considering the determined orthotropic properties, can be applied to the thermoforming of various three-dimensional shapes.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2000년도 추계학술발표강연 및 논문개요집
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• pp.137-137
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• 2000

• ETRI Journal
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• 제25권2호
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• pp.73-80
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• 2003

This paper describes an effective method for forming silicon oxide on silica-on-silicon platforms, which results in excellent characteristics for hybrid integration. Among the many processes involved in fabricating silica-on-silicon platforms with planar lightwave circuits (PLCs), the process for forming silicon oxide on an etched silicon substrate is very important for obtaining transparent silica film because it determines the compatibility at the interface between the silicon and the silica film. To investigate the effects of the formation process of the silicon oxide on the characteristics of the silica PLC platform, we compared two silicon oxide formation processes: thermal oxidation and plasma-enhanced chemical vapor deposition (PECVD). Thermal oxidation in fabricating silica platforms generates defects and a cristobalite crystal phase, which results in deterioration of the optical waveguide characteristics. On the other hand, a silica platform with the silicon oxide layer deposited by PECVD has a transparent planar optical waveguide because the crystal growth of the silica has been suppressed. We confirm that the PECVD method is an effective process for silicon oxide formation for a silica platform with excellent characteristics.

• 한국전기전자재료학회논문지
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• 제19권11호
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• pp.985-993
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• 2006

An experiment to find out the removal mechanism of PEG(polyethyleneglycol) by using UV-enhanced $O_2$ GPC (gas phase cleaning) at low substrate temperature below $200^{\circ}C$ was executed under various process conditions, such as substrate temperature, UV exposure, and $O_2$ gas. The possibility of using $UV/O_2$ GPC as a low-temperature in-situ cleaning tool for organic removal was confirmed by the removal of a PEG film with a thickness of about 200 nm within 150 sec at a substrate temperature of $200^{\circ}C$. Synergistic effects by combining photo-dissociation and photo oxidation can only remove the entire PEG film without residues within experimental splits. In $UV/O_2$ GPC with substrate temperatures higher than the glass transition temperature, the substantial increase in the PEG removal rate can be explained by surface-wave formation. The photo-dissociation of PEG film by UV exposure results in the formation of end aldehyde by dissociation of back-bone chain and direct decomposition of light molecules. The role of oxygen is forming peroxide radicals and/or terminating the dis-proportionation reaction by forming peroxide.

• 한국인터넷방송통신학회논문지
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• 제9권3호
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• pp.173-178
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• 2009

금속산화물 박막 소자를 제작하여 전기적 특성을 조사하였다. 소자는 Electrode를 TOP-TOP구조로 제작하였으며 스위칭 특성을 연구하기 위해 전극간의 산화금속박막의 전도특성이 측정되었다. 소자의 저항변화는 전압을 선형적으로 인가하여 측정하였다. 제작된 소자는 MIM구조로써 외부에서 인가하는 전기적 신호에 의하여 전기전도도가 큰 On-state와 전기전도도가 낮은 Off-state로 바뀌는 특성을 나타내었다. $Si/SiO_2/MgO$ 소자는 Forming에 의해 저항이 큰 상태에서 저항이 작은 상태로 전기적 특성이 변화하면서 스위칭 특성을 보였다. 본 연구를 통하여 산화금속은 차세대 비휘발성 메모리로는 물론 다른 전기적 응용이 기대되는 물질임을 확인하게 되었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전기물성,응용부문
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• pp.55-56
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• 2006

We investigated the diffraction grating efficiency by the DPSS laser beam wavelength to improve the diffraction efficiency on AsGeSeS & Ag/ AsGeSeS thin film. Diffraction efficiency was obtained from DPSS(532nm)(P:P)polarized laser beam on AsGeSeS, Ag/ AsGeSeS and AsGeSeS/Ag/AsGeSeS thin films. As a result, for the laser beam intensity, 0.24 mW, single AsGeSeS thin film shows the highest value of 0.161% diffraction efficiency at 300 s and for 2.4 mW, it was recorded with the fastest speed of 50 s, which the diffraction grating forming speed is faster than that of 0.24 mW beam. Ag/ AsGeSeS and AsGeSeS/ Ag/ AsGeSeS multi-layered thin film also show the faster grating forming speed at 2.4 mW and higher value of diffraction efficiency at 0.24 mW.

• 설비공학논문집
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• 제18권11호
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• pp.867-873
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• 2006

Vertical falling liquid film is extensively used in heat and mass transfer processes of many applications, such as evaporative coolers, cooling towers, and absorption chillers. In such cases, it is required that the falling film spreads widely in the surface forming thin liquid film to enlarge contact surface. An addition of surface active agent to a falling liquid film or hydrophilic surface treatment affects the fluid physical properties of the film. Surfactant addition not only decreases contact angle between the liquid and solid surface but also changes the surface from hydrophobicity to hydrophilicity. In this study, the effects of contact angle on falling film characteristics over a vertical surface have been investigated experimentally. The contact angle is varied either by an addition of surfactant to the liquid or by hydrophilic surface treatment. It is found that the wetted area is increased and film thickness is decreased by the hydrophilic treatment as compared with those of other surfaces. With this hydrophilic treatment, the falling liquid film spreads out widely in the surface. As surfactant concentration is increased, wetted area is also increased and the film thickness is substantially decreased.

• 치위생과학회지
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• 제23권2호
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• pp.88-92
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• 2023

Background: Aphthous stomatitis is a common disease of the oral mucosa and its pathogenesis is associated with several risk factors. Frequently, minor ulcers are idiopathic in nature and often resolve naturally. However, those ulcers are painful and sensibly compromise patients' eating. There are different treatment strategies for the clinical management of oral aphthae. Methods: The present study assessed the efficacy of a film-forming cream in accelerating the healing and diminishing the pain associated with minor aphthae in a randomized fashion design. The test product (AphtoFix^®) was compared with placebo cream in a cohort of patients with a diagnosis of minor recurrent stomatitis. Patients were randomly distributed into two groups and were followed for 10 days. The primary outcomes included the number of days until symptoms were relieved and the number of days to complete healing. Results: Thirty-six patients completed the follow-up, eighteen per group. All lesions eventually healed within day 10. However, patients in the test group experienced significantly less pain, already from day 1. Patients in the test group also showed a faster healing rate of the lesion with an average of 7 days against the 9 days required for patients in the control group. Conclusion: The present study supported the utility of a film-forming in cream in relieving the patient from symptoms associated with aphthous stomatitis already at day 1 of product use. Patients also displayed faster healing of the lesions when compared to the control group. Further studies with greater sample size and patient stratification according to age and risk factors are recommended to support the present findings.

• 한국축산식품학회지
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• 제35권5호
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• pp.611-614
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• 2015

This study was performed to apply a protein film containing a natural antimicrobial compound to meat packaging and determine quality change of meat during storage. Proteins obtained from the by-products of food processing have been utilized as biodegradable film sources. Porcine meat and bone meal (MBM) is obtained during meat processing, and proteins from the MBM can be extracted and used as a film base material. Previously, an antimicrobial MBM film containing coriander oil (CO) was prepared and its physical properties and antimicrobial activity were characterized. In this study, the antimicrobial MBM-CO film was applied to beef patties packaging, and the microbial population and the degree of lipid oxidation were determined during storage at 4℃ for 15 d. The population of inoculated E. coli O157:H7 in the samples wrapped with the MBM-CO film was 6.78 log colony forming unit (CFU)/g after 15 d of storage, whereas the control had 8.05 Log CFU/g, thus reducing the microbial population by 1.29 Log CFU/g. In addition, retardation of lipid oxidation in the patties was observed during storage for the samples packaged by the MBM-CO film, compared with the control samples. These results suggest that the MBM-CO film can be useful for enhancing the quality of beef patties during storage.

• Journal of Microbiology and Biotechnology
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• 제17권3호
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• pp.520-523
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• 2007

Edible films of gelatin and com zein were prepared by incorporating nisin to the film-forming solutions. Com zein film with nisin of 12,000 IU/ml had an increase of 11.6 MPa in tensile strength compared with the control, whereas gelatin film had a slight increase with the increase of nisin concentration added. Water vapor permeability for both com zein and gelatin films decreased with the increase of nisin concentration, thus providing a better barrier against water. Antimicrobial activity against Listeria monocytogenes increased with the increase of nisin concentration, resulting in 1.4 log cycle reduction for com zein film and 0.6 log cycle reduction for gelatin film at 12,000 IU/ml. These results suggest that incorporation of nisin into com zein and gelatin films improve the physical properties of the films as well as antimicrobial activity against pathogenic bacteria during storage, resulting in extension of the shelf life of food products by providing with antimicrobial edible packaging films.