• 설비공학논문집
• /
• 제27권11호
• /
• pp.574-580
• /
• 2015

Climatic zone in building code is an administrative district classification reflecting regional climatic characteristics. Use of Degree-Days is a fundamental method that can be used in various building design codes, analysis of building energy performance, and establishment of minimum thermal transmittance of building envelopes. Many foreign countries, such as the USA, the EU, Australia, Italy, India, China, etc., have already adapted climatic zone classification with degree-days, precipitation or amount of water vapor based on the characteristics of their own country's climate. In Korea, however, the minimum requirements for regional thermal transmittance are classified separately for the Jungbu area, Nambu area and Jeju Island with no definite criterion. In this study, degree-days of 255 Korean cities were used for climatic zone classification. Outdoor dry-bulb temperature data from the Korea Meteorological Administration for 1981~2010 was used to calculate degree-days. ArcGIS and the calculated degree-days were utilized to analyze and visualize climatic zone classification. As a result, depending on the distribution and distinctive differences in degree-days, four climatic zones were derived : 1) Central area, 2) Mountain area of Gyeonggi and Gangwon provinces, 3) Southern area, and 4) Jeju Island. The climatic zones were suggested per administrative district for easy public understanding and utilization.

• 한국포장학회지
• /
• 제20권1호
• /
• pp.7-15
• /
• 2014

Agar-based composite films were prepared with variety of food processing and agricultural processing waste materials in order to screen natural lingo-cellulosic resources for the value-added utilization of the under-utilized materials. The effect of these waste materials (10 wt% based on agar) on mechanical properties, moisture content (MC), water vapor permeability (WVP), water absorption behavior of biocomposite films were investigated. Biocomposite films prepared with various fibers resulted in significant increase or decrease in color and percent transmittance. The MC, WVP, and surface hydrophobicity of biocomposite films increased significantly by incorporation of fibers, while the water uptake ratio and solubility of the film decreased. SEM images of biocomposite film showed better adhesion between the fiber and agar polymer. Among the tested cellulosic waste materials, rice wine waste, onion and garlic fibers were promising for the value-added utilization as a reinforcing material for the preparation of biocomposite food packaging films.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
• /
• pp.746-749
• /
• 2002

Aluminum oxide thin films were grown on a poly ethylene naphthalate (PEN) substrate at the temperature of 100$^{\circ}C$ using atomic layer deposition method. The film showed very flat morphology and good adhesion to the substrate. The visible spectrum showed higher transmittance in the range from 400 nm to 800 nm than that of PEN. The water vapor transmission value measured with MOCON for 230nm oxide-deposited PEN was 0.62g/$m^2$/day @ 38$^{\circ}C$, while that of PEN substrate was 1.4g/$m^2$/day @ 38$^{\circ}C$.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2009년도 제38회 동계학술대회 초록집
• /
• pp.178-178
• /
• 2010

We have deposited aluminum-doped ZnO thin films on borosilicate glass by atomic layer deposition. Diethylzinc (DEZ) and dimethylaluminum isopropoxide (DMAIP) were used as the metal precursor and the Al-dopant, respectively. Water was used as an oxygen source. DMAIP was successfully used as an aluminum precursor for chemical vapor deposition and ALD. All deposited films showed n-type conduction. The resistivity decreased to a minimum and then increased with increasing the aluminum content. The carrier concentration increased and the carrier mobility decreased with increasing the DMAIP to DEZ pulse ratio. The average optical transmittance was nearly 80 % in the visible part of the spectrum. The absorption edge moved to the shorter wavelength region with increasing the DMAIP to DEZ pulse ratio. Our results indicate that DMAIP is suitable for Al doping of ZnO films.

• 반도체디스플레이기술학회지
• /
• 제16권4호
• /
• pp.1-4
• /
• 2017

Encapsulation of organic based devices is essential issue due to easy deterioration of organic material by water vapor. Atomic layer deposition (ALD) is a promising solution because of its low temperature deposition and quality of the deposited film. Moisture permeation has a mechanism to pass through defects, Thin Film Encapsulation using inorganic / organic / inorganic hybrid film has been used as promising technology. $Al_2O_3$ / Polymer / $Al_2O_3$ multilayer film has shown excellent environmental protection characteristics despite of thin thicknesses of the films.

• Journal of Information Display
• /
• 제11권1호
• /
• pp.8-11
• /
• 2010

In this study, a new thin films passivation technique using Zn with high electronegativity and $MgF_2$, a fluorine material with better optical transmittance than the sealing film materials that have thus far been reported was proposed. Targets with various ratios of $MgF_2$ to Zn (5:5, 4:6 and 3:7) were fabricated to control the amount of Zn in the passivation films. The Mg-Zn-F films were deposited onto the substrates and Zn was located in the gap between the lattices of $MgF_2$ without chemical metathesis in the Mg-Zn-F films. The thickness and optical transmittance of the deposited passivation films were approximately 200 nm and 80%, respectively. It was confirmed via electron dispersive spectroscopy (EDS) analysis that the Zn content of the film that was sputtered using a 4:6 ratio target was 9.84 wt%. The Zn contents of the films made from the 5:5 and 3:7 ratio targets were 2.07 and 5.01 wt%, respectively. The water vapor transmission rate (WVTR) was determined to be $38^{\circ}C$, RH 90-100%. The WVTR of the Mg-Zn-F film that was deposited with a 4:6 ratio target nearly reached the limit of the equipment, $1\times10^{-3}\;gm^2{\cdot}day$. As the Zn portion increased, the packing density also increased, and it was found that the passivation films effectively prevented the permeation by either oxygen or water vapor. To measure the characteristics of gas barrier, the film was applied to the emitting device to evaluate their lifetime. The lifetime of the applied device with passivation was increased to 25 times that of the PLED device, which was non-passivated.

• 한국포장학회지
• /
• 제20권2호
• /
• pp.41-49
• /
• 2014

This study illustrates the synthesis of gelatin based zinc oxide nanoparticle (ZnONPs) incorporated nanocomposite films using different concentrations of ZnONPs. The ZnONPs were oval in shape and the size ranged from 100- 200 nm. The nanocomposite films were characterized by UV-visible, FE-SEM, FT-IR, and XRD. The concentrations of ZnONPs greatly influenced the properties of nanocomposite films. The absorption peaks around 360 nm increased with the increasing concentrations of ZnONPs. The surface color of film did not change while transmittance at 280 nm was greatly reduced with increase in the concentration of ZnONPs. FTIR spectra showed the interaction of ZnONPs with gelatin. XRD data demonstrated the crystalline nature of ZnONPs. The thermostability, char content, water contact angle, water vapor permeability, moisture content, and elongation at break of nanocomposite films increased, whereas, tensile strength and modulus decreased with increase in the concentrations of ZnONPs. The gelatin/ZnONPs nanocomposite films showed profound antibacterial activity against both Gram-positive and Gram-negative food-borne pathogenic bacteria. The gelatin/$ZnONP^{1.5}$ nanocomposite film showed the best UV barrier and antimicrobial properties among the tested-films, which indicated a high potential for use as an active food packaging films with environmentally-friendly nature.

• Journal of Plant Biotechnology
• /
• 제7권1호
• /
• pp.67-74
• /
• 2005

To overcome various disadvantages of conventional cul-ture vessels for micropropagation, a novel disposable vessel, the 'Vitron', made of a multi-layered $OTP^{(R)}$ film and supported by a polypropylene frame, was developed. The film possesses superior properties such as: high light transmittance, low water vapor transmittance and thermal stability and in particular, high gas-permeability. Single nodal explants, which were excised from the multiple shoots derived from shoot-tip culture, were cultured in Vitron and polycarbonate vessels on $3\%$ sugar-containing agar on MS medium and placed at 3000 ppm $CO_2$-enrichment at a low photosynthetic photon flux density (PPFD) ($45{\mu}mol\;m^{-2}\;s^{-1}$). The in vitro and ex vitro growth, and the net photosynthetic rate of in vitro and ex vitro plantlets were significantly enhanced in the Vitron compared to those cultured in a polycarbonate vessel. Explants that were cultured on the same MS medium under low PPFD at various $CO_2$ concentrations were also cultured at 3000 ppm $CO_2$- enrichment at various PPFD: 30, 45, 60, 75 and $90{\mu}mol\;m^{-2}\;s^{-1}$. The best in vitro and ex vitro growth obtained for 3000 ppm $CO_2$-enrichment at $75{\mu}mol\;m^{-2}\;s^{-1}$ PPFD. The novel Vitron vessel, when placed under the two conditions, may replace conventional culture vessels for the successful micropropagation of sweetpotato.

• 센서학회지
• /
• 제28권6호
• /
• pp.402-406
• /
• 2019

Recently, semiconducting organic materials have been spotlighted as next-generation electronic materials based on their tunable electrical and optical properties, low-cost process, and flexibility. However, typical organic semiconductor materials are vulnerable to moisture and oxygen. Therefore, an encapsulation layer is essential for application of electronic devices. In this study, SiN_x thin films deposited at process temperatures below 150 ℃ by plasma-enhanced chemical vapor deposition (PECVD) were characterized for application as an encapsulation layer on organic devices. A single structured SiN_x thin film was optimized as an organic light-emitting diode (OLED) encapsulation layer at process temperature of 80 ℃. The optimized SiN_x film exhibited excellent water vapor transmission rate (WVTR) of less than 5 × 10^-5 g/㎡·day and transmittance of over 87.3% on the visible region with thickness of 1 ㎛. Application of the SiN_x thin film on the top-emitting OLED showed that the PECVD process did not degrade the electrical properties of the device, and the OLED with SiN_x exhibited improved operating lifetime

• 한국산학기술학회논문지
• /
• 제4권3호
• /
• pp.199-203
• /
• 2003

In this study plastic optical fibers (POFs) were considered as light-transmitting media and substrates for the potential use in photocatalytic environmental purification system. After the characteristics of POFs in terms of light transmittance and absorption were determined at the beginning, the further investigation was performed through the photocatalytic degradation of trichloroethylene (TCE), iso-propanol and etc. with TiO$_2$-coated optical fiber reactor systems (POFR). It is concluded that the use of POFs is preferred to quartz optical fibers (QOFs) since the advantages such as ease of handling, lower cost, relatively reasonable light attenuation at the wavelength of near 400nm can be obtained. Various geometrical reactor shapes have been constructed and applied for the last one and half years. For the use of POF in water phase treatment, however, more detailed scientific and engineering aspects should be envisaged. This case requires a suitable mixture to obtain more stable and innocuous immobilization of photocatalyst on POF. To overcome this disadvantage, metal-organic chemical vapor deposition (MOCVD) was conducted in a fluidized bed to deposit thin films of titania on glass and alumina beads. Those can be used as photocatalysis for the removal of pollutants especially in liquid phases.