• Journal of Energy Engineering
• /
• v.13 no.2
• /
• pp.93-100
• /
• 2004

The smear media possible to sampling and radiation detection was prepared and evaluated for the surface contamination using indirect method. The films were made by impregnating Cerium Activated Yttrium Silicate (CAYS) in a polysulfone membrane. The membranes used solution as a dimethylformamide (DMF) and methylene chloride (MC), polysulfone as a polymer matrix and CAYS as a inorganic scintillator. The proximity membranes were prepared with single- and double-layered structure. The solidified methods were immersion to the nonsolvent bath such at water and ethanol and solvent evaporation. The measurement of the photon produced by interaction with radiation and inorganic scintillator used a photomultiflier tube (PMT), amplifier, and counter. In the comparison with the low background alpha/beta counter, the counter rate using inorganic scintillator proximity membrane for the $\^$14/C surface contamination was about 50%. Also. the $^3$H counting results revealed that the prepared membranes were efficient to monitor the surface contaminated with the low energy be-ray emitter nuclides.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.2
• /
• pp.567-572
• /
• 2013

In houses that use heating and cooling system, most of heat loss occurs through the windows, so that low-E glass, double-layered glass, and vacuum glazing are used to minimize the heat loss. In this paper, an encapsulating process that is a final process in manufacturing the vacuum glazing has been studied, and bonding in a vacuum chamber rather than atmospheric bonding was considered. For the efficiency of the encapsulating process, frit-melting temperature and bonding time were optimized with heater temperature, and the glass preheating temperature was optimized to prevent glass breakage due to thermal stress. Thus the vacuum glass was successfully manufactured based on these results and heat transmission coefficient measured was about $5.7W/m^2K$ which indicates that the internal pressure of the vacuum glazing is $10^{-2}$ torr.

• Journal of the Mineralogical Society of Korea
• /
• v.29 no.2
• /
• pp.35-45
• /
• 2016

Clays, which are abundant in nature and eco-friendly, have been utilized throughout human history due to their characteristic physicochemical properties. Recently, a variety of clays such as montmorillonite, kaolinite, sepiolite and layered double hydroxide with or without chemical modification have been extensively studied for potential application in industries. Clays that possess a large specific surface area, high aspect ratio, nanometer sized layer thickness and controllable surface charge could be utilized as polymer fillers after appropriate chemical modifications. These modified clays can improve mechanical and gas barrier properties of polymer materials but also provide sustained antibacterial activity to polymer films. Furthermore, engineered clays can be utilized as scavengers for chemical or biological pollutants in water or soil, because they have desirable adsorption properties and chemical specificity. In this review, we are going to introduce recent researches on engineered clays for potential applications in future industries such as food packaging and environmental remediation.

• Journal of the Korean Geotechnical Society
• /
• v.15 no.5
• /
• pp.29-41
• /
• 1999

This Paper applied a simple strength parameter averaging method to double layered systems consisting of the strong sand layer overlying the soft clay deposit. This study derived a formula which defines a critical depth as the strength parameters, and used the correction parameter, $\alpha$ to reduce an error of the strength parameter averaging method. The results of the method were presented in the form of dimensionless charts and were compared with the results of several solutions proposed by Satyanarayana & Grag, Sreenivasulu, and Meyerhof & Hanna. The results of the proposed method coincided with the method of Meyerhof & Hanna and the results obtained from FLAC. But the Satyanarayana & Grag method and the Sreenivasulu method overestimated the bearing capacity. Consequently, the bearing capacity of foundation on sand layer overlying soft clay layer can be approximately estimated by using the proposed dimensionless charts.

• Journal of the Korean Society of Costume
• /
• v.50 no.2
• /
• pp.125-140
• /
• 2000

The major findings of basic women wear in genre painting were ; 1. Due to the influence of Shill-Hak (practical science) philosophy, Jeogori became shorter and a tighter fit came to be the norm. 2,. The shortening of the Jeogori influenced a longer Chima with a wider span providing comfort in movement or at work. The end of the skirt was often held by one hand to the waist adding to comfort. This was called the Go-dul-chima(Lifted Chima). 3. Because the Geo-dul-chima exposed a portion of one underwear at the bottom of the dress this influenced the "irnamentation' of underpants and underskits. 4. Collars or lapels came in the form of Dang-ko, Kal, Mok-pan and Ban-Mokpan. Among there Dang-ko style collars were the most common which allows us to conclude that this was the most popular. 5. The most commonly used colors for Jeogori were white (39.8%) and jade(18.3%) . The most commonly used colors for CHima were deep blue(34.4%) and jade(20.4%) . The lower Chima used the darkercolors to give stability to the overall costume. 6. Clothing had the function of differentiating the classes. Only the Yang-ban were allowed to wear the Samhijang Jeogori and the Gob-Chima(double layered Chima) and the knotting of the Chima to the left. But the painting show that these rules were not adhered to in the strictest manner. With the bases of these types of chima and Jeogori can look at the characteristical beauty of the ordinary women during the late Cho-sun dynasty. First is the beauty which comes from mystery of those parts of body which can not be seen. A sense of subtle and sensual beauty as well as that coming from the enlargement of reduction of the upper body, narrow waist and abundant lower body parts creating an ideal silhouette of sexual charm. An expression of emotion through clothing by those who lived during those times.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.20 no.1
• /
• pp.1-6
• /
• 2014

Properly designed plastic packages of fresh produce can preserve the quality by maintaining the optimal modified atmosphere (MA) at optimal low temperature conditions, but cannot do so at temperature abuse conditions in retail stage due to occurrence of injurious package atmosphere coming from imbalance between respiration and package gas permeation. Master packaging system consisting of a double-layered secondary package wrapping several individual (primary) packages has been proposed and applied recently to the commodities of sweet persimmon, king oyster mushroom, chestnut and strawberry. The master (secondary) pack is designed to be stored and distributed under chilled temperature, and then dismantled when moved to the retail display from the presale chilled storage. The master packaging system taking into consideration temperature dependence of produce respiration and package gas transfer was looked into with examination of its design variables to maintain the beneficial MA. Mathematical model was provided to help the design of master packaging system creating the desired MA. Its benefits of quality preservation and its limitations in practices of fresh produce marketing were discussed. Further research direction to extend the applicability of the produce master packaging system was presented.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.33 no.2
• /
• pp.219-225
• /
• 2013

Separate and layered transmitting and receiving spiral coil arrays had been used for the optimized individual applications of magnetostrictive type long-range ultrasonic testing. In this study, it was demonstrated that when taking advantages of the spiral coils with the leg width reduced to be half of the previous one and of the empty spaces due to the decrease of leg width, the transmitting and receiving coil array can be arranged to form a single layer structure allowing more easy use and fabrication. Because of the number of turns of the receiving coils that is proportional to their leg width, the sensitivity of the single layer coil array was about half that of the corresponding double layer coil array while it allowed the receiving amplifier to get faster recovery from a saturation due to the main bang echo. It was also found that the two types of coil arrays have almost the same performances in the view points of signal-to-noise ratio and directivity control.

• Journal of Powder Materials
• /
• v.13 no.2 s.55
• /
• pp.144-149
• /
• 2006

In this research we tried to make nano-sized TiNx by using planetary milling, and we made the composites double layered of titanium and nano-sized TiNx by using spark plasma sintering apparatus after mixing with the different ratio of pure titanium powder, and they were heat treated at $850^{\circ}C$ for 30 minutes. The crystal structures of nano-sized TiNx powders and the composites were analyzed by X-ray diffraction (XRD). The microstructures of the powders were analyzed by using scanning electron microscopy (FESEM) and the 40-50 nm size of nano-sized TiNx particle on the surface of agglomerated particles was investigated. With increasing the ratio of nano-sized TiNx of the composites, the microvickers hardness of the composites was increased.

• Journal of the Korean institute of surface engineering
• /
• v.49 no.5
• /
• pp.454-460
• /
• 2016

Double-layered Al-Mg films have been deposited by using an e-beam deposition method on a cold-rolled steel sheet(CR), which the structure of the film was Al/Mg/CR. The micro-structure, alloy phase, and corrosion resistance of the Al-Mg coated CR were investigated before and after heat treatment at $400^{\circ}C$ for 2, 3, and 10 min in a nitrogen atmosphere. Total thickness of Al-Mg films was fixed at $3{\mu}m$ and the thickness ratio of Al and Mg layers(Al:Mg) has been changed from 5:1 to 1:5. The cross-sectional morphology of the films, which had the thickness ratio of 2:1(Al:Mg), 1:1, and 1:2, was changed after heat treatment from columnar to featureless structure. The x-ray diffraction data for as-deposited films showed only pure Al and Mg peaks. Al-Mg alloy peaks such as $Al_3Mg_2$ and $Al_{12}Mg_{17}$ phase appeared after the heat treatment. The Al-Mg coating with the thickness ratio of 1:1(Al:Mg) showed the best corrosion resistance of up to 500 hours by salt spray test.

• Applied Microscopy
• /
• v.22 no.2
• /
• pp.66-74
• /
• 1992

In an attempt to produce transgenic amphibia, bacteriophage ${\lambda}-DNA$ was microinjected into fertilized eggs of Xenopus laevis, and the effect on early embryogenesis and the ultrastructural behavior of exogenous DNA were investigated. The effect of microinjected gene on embryonic development showed differences according to the concentration of injected DNA and the incubation temperature. Various concentrations of ${\lambda}-DNA$ were tested. Among those, microinjection of 1-2 ng DNA dissolved in 20 nl TE buffer was not shown to disturb normal embryonic development and was recorded the highest survivability to the late tadpole stage (Stage 43); however, injection of increased concentrations of DNA than above provoked irregular cleavages or abnormal appearances, which resulted in reduced survivability. When the injected embryos were incubated at low temperatures (e.g., $12^{\circ}C$), 54.5% of the embryos developed to Stage 43, whereas 42.4% survived when incubated at room temperature. The survivability showed also differences according to the injection site. 58.0% of the embryos developed to Stage 43 when microinjected into the vegetal pole, whereas 44.9% survived when microinjected into the animal pole. To understand the structural fate or behavior of injected DNA a combined light and electron microscopical study was applied. The nucleus-like structure was observed in the ${\lambda}$ DNA-injected embryos, which was quite a similar to the interphase nuclei of normal Xenopus laevis. The nucleus-like structure showed the typical double-layered nuclear membrane and nuclear complexes; however, it consisted of unusual structures such as furrows of nuclear envelope into the nucleoplasm.