• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.5
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• pp.541-544
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• 2004

Multi- wall carbon nanotubes(MWNTs) were synthesized by thermal chemical vapor deposition. The paste for screen printing was composed of MWNTs, organic vehicle and glass frit. Carton nanotube paste was screen-printed on ITO(indium tin oxide) deposited soda lim을 glass, and then heat treatment was performed. Before the surface treatment, turn on field of derive was 2.6 V/$\mu\textrm{m}$. After the surface treatment, the value was changed into 1.8 V/$\mu\textrm{m}$. The anode current of the derive with 2.83 V/$\mu\textrm{m}$(turn on field) was changed 4 $\mu\textrm{A}$ into 390 $\mu\textrm{A}$ at 1,700 V. Adsorption effect of MWNTs onto phosphor of anode plate was observed by the field emission measurement and resulted in bad effects on properties of devices lifetime and emission lighting.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.2
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• pp.500-507
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• 2008

By Using various grinding mill in powder cosmetics manufacturing process; screen milt and pin mill, jet mill, properties of the powder and grinding mills were studied; talc, mica, nylon powder, silica, titanium dioxide. Besides, the experiments fur evaluation of grinding were performed by using iron oxides those are tracers. In powders of plate shape, they were grinded more vertically than horizontally at the screen mill and pin mill, although were all grinded vertically and horizontally at the jet mill. The spheric powders became the primary particles or aggregation by electrostatic interaction at the screen mill and pin mill. But, at the jet mill, they resulted the agglomeration or transformation or damage up to 2bar. Titanium dioxides became the primary particles by all grinding mill. Pin mill has an excellent result in experiments which is a change of the tone of color by grinding. From these results, suggest that the jet mill is used to pre-treat of powders of plate shape in practical cosmetic manufacturing process, and the screen mill and pin mill are used to match the color of powder cosmetics. If industrial process condition is taken into consideration, suggest that 4times of grinding is excellent on grinding effect by the screen mill, and twice grinding by the pin mill and grind air pressure of 1bar by the jet mill.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.2 s.120
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• pp.1-8
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• 2007

To examine the feasibility of dry forming technology for papermaking, a dry forming mold (DFM) was developed and evaluated. Main fanning section of DFM was a cylindrical tube, and at the top of the mold a stirring equipment was placed to disperse dry fibers. These fibers were screened using a hole type screen plate placed just under the stirring equipment and dropped freely on the fanning wire located 0.9 m below of the screen plate to form a dry fiber pad. The vertical and horizontal velocity of air flow in the forming cylinder were evaluated and analyzed to find the most effective method of air flow control in the cylinder. Humidification and pressing conditions to obtain a decent dry fanned papers were examined. Results showed dry fanned papers can be prepared with this dry forming mold. And this mold can be used to examine the effect of the papermaking process factors including pressing pressure, drying temperature, humidification on sheet quality of dry formed papers.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.7
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• pp.1759-1772
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• 1994

In this study, we re-examined the Tate's modified Bernoulli equation to study penetration phenomena for long rod projectile into single or multi-layered finite thickness plates. We used the force equlibrium equation at mushroomed nose/target interface instead of conventional pressure equation at the stagnation point. In our penetration model, we considered the velocity dependent $R_t$ value for semi-infinite target and considered only the back face effect for finite target. To compensate for $R_t$ value according to target's thickness and back face effect, we used the spherical cavity expansion theory for semi-infinite plate and used the cylindrical cavity expansion theory for finite plate. Also we developed the experimental technique using make screen to measure the penetration duration time at each layered plate. In 3-layered laminated RHA/mild steel/ A1 7039 plate, we observed that spall had occured around the back face of A1 7039 plate by the stress wave interaction. Through the comparison between theoretical and experimental data including Lambert's results, we conform that our study has good confidences.

• Journal of Power System Engineering
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• v.13 no.2
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• pp.11-17
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• 2009

The heat transfer characteristics of flow through two inclined wire-mesh baffles in a rectangular channel were investigated experimentally with varying the mesh number of wire screens and inclination angle of the baffles. Two different types of wire meshes such as dutch and plain weaves, were used in this experiment. Three kinds of baffle plates with different mesh specifications in the dutch weave and four different kinds in the plain weave were manufactured. Baffles were mounted on bottom wall with varied angles of inclination. Reynolds number was varied from 23,000 to 57,000. It is found that the placement of inclined wire-mesh baffles in the channel affects the heat transfer characteristics by combining both jet impingement and flow disturbance. The wire screen modified the flow structure leading to a change in the heat transfer characteristics. The results show that the baffle plate with the most number of mesh (type SA) has the highest heat transfer rate.

• Korean Journal of Digital Imaging in Medicine
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• v.2 no.1
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• pp.92-95
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• 1996

Computed Radiography(CR) is a relatively new technology that relies on an image plate(IP) as an alternate x-ray sensor to screen/film. Standard CR cassettes do not have lead foil behind the IP to control scatter radiation. The result of this study indicate that such control is needed. In most screen/film cassettes, that lines the rear of the cassette eliminates back scatter radiation. This study was performed to Investigate on the effects of back scatter in CR images by size of exposure field, distance between the CR cassette and the wall of radiography room. 1. It showed artifacts from hinges and clips located on the back of CR cassette by back scatter radiation. 2. The greater effects of back scatter radiation in CR images was attributed to the greater size of exposure field and the longer distance between the CR cassette and the wall of radiography room.

• Food Science of Animal Resources
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• v.18 no.3
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• pp.203-208
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• 1998

The study was carried out to screen mutagenicity of smoking materials for the determination of optimum smoking temperature for meat products. Wood materials employed for smoking were oak and apple trees. Temperatures of the generator for manufacturing of smoke flavoring were set to 250$^{\circ}C$, 400$^{\circ}C$ and 500$^{\circ}C$, respectively. Mutagenic activities of smoke flavoring were assayed according to Ames test using Salmonella typhimurium TA98 and TA 100. In oak wood smoke flavoring, Salmonella typhimurium TA98 without S-9 mix showed strong mutagenic activities at the concentration of 6$\mu\textrm{g}$/plate(250$^{\circ}C$), 4$\mu\textrm{g}$/plate(400$^{circ}C$) and 6$\mu\textrm{g}$/plate(500$^{\circ}C$). Salmonella typhimurium TA100 with S-9 mix showed strong mutagenic activities at the concentration of 10$\mu\textrm{g}$/plate(250$^{\circ}C$), 20$\mu\textrm{g}$/plate(400$^{\circ}C$) and 10$\mu\textrm{g}$/plate(500$^{\circ}C$). Salmonella typhimurium TA98 with S-9 mix showed strong mutagenic activities at the concentration of 30$\mu\textrm{g}$/plate(250$^{\circ}C$), 40$\mu\textrm{g}$/plate(400$^{\circ}C$) and 20$\mu\textrm{g}$/plate(500$^{\circ}C$). Salmonella typhimurium TA100 with S-9 mix showed strong mutagenic activities at the concentration of 30$\mu\textrm{g}$/plate(250$^{\circ}C$), 50$\mu\textrm{g}$/plate(400$^{\circ}C$) and 20$\mu\textrm{g}$/plate(500$^{\circ}C$). Salmonella typhimurium TA100 without S-9 mix showed strong mutagenic activities at the concentration of 10$\mu\textrm{g}$/plate(250$^{\circ}C$), 20$\mu\textrm{g}$/plate(400$^{\circ}C$) and 20$\mu\textrm{g}$/plate(500$^{\circ}C$). Salmonella typhimurium TA98 with S-9 mix showed strong mutagenic activities at the concentration of 30$\mu\textrm{g}$/plate(250$^{\circ}C$), 40$\mu\textrm{g}$/plate(400$^{\circ}C$) and30$\mu\textrm{g}$/plate(500$^{\circ}C$). Salmonella typhimurium TA100 with S-9 mix showed strong mutagenic activities at the concentrations 30$\mu\textrm{g}$/plate(500$^{\circ}C$). Salmonella typhimurium TA100 with S-9 mix showed strong mutagenic activities at the concentration of 30$\mu\textrm{g}$/plate(250$^{\circ}C$), 20$\mu\textrm{g}$/plate(400$^{\circ}C$) and 30$\mu\textrm{g}$/plate(500$^{\circ}C$). From these results, it could be concluded that optimum smoking temperature for meat products should be set below 400$^{\circ}C$, that the compounds like benzo[a]pyrene etc. contain a variety of mutagenic potentials, which could be generated at the higher smoking temperature.

• Journal of Radiation Protection and Research
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• v.29 no.4
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• pp.231-236
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• 2004

An imaging plate(IP) detector, a two-dimensional digital radiation detector that can acquire image of radioactivity distribution in a sample, has been applied in many fields; for industrial radiography, medical diagnosis, X-ray diffraction test, etc. In this study, the possibility of IP detector to be used lot measuring radioactivity of sample is explored using its high sensitivity, higher spatial resolution, wider dynamic range and screen uniformity for several kinds radiations. First, the IP detector is applied to measure the surface uniformity for area source. Surface uniformity is measured rapidly and nondestructively by measuring the radioactivity distribution of common standard area source$(^{241}Am)$. Next, the IP is employed to study the possibility of measuring an extremely low-level activity of environmental sample. For this study the screen uniformity, shield effect of background radiation, linear dynamic range and fading effect of the IP detector is investigated. The potato, banana, radish and carrot samples are chosen to measure ultra low-level activity of $^{40}K$ isotope. The efficiency calibration of IP detector is carried out using the standard source.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.04a
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• pp.260-265
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• 2006

• Proceedings of The Korean Cleft Lip And Palate Association
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• 2003.06a
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• pp.47-47
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• 2003