• Proceedings of the Korea Contents Association Conference
• /
• 2006.11a
• /
• pp.520-523
• /
• 2006

Lately, development of multimedia industry has multimedia data serviced through various wire wireless communicating environment. These multimedia data is displayed on the device of various sizes such as mobile telephone, PDA, notebook, PC. Therefore, there has needed to resize multimedia data appropriate to the screen size of user's display device. In this paper, we propose the method to resizing H.264 videos sequence fitting to the screen size of user's display device. The existing most methods reduce the size of video sequence, but this paper proposes the upsampling method. The results show the proposed method upsamples video sequences without blocking effects.

• Fire Science and Engineering
• /
• v.22 no.5
• /
• pp.83-89
• /
• 2008

Using the high expansion foam generator of ISO 7203-2 which spray 6 liter at 5 bar, foam generation characteristics was studied. Wind flow rate, foam screen, concentration of foam agent solution and concentration of salt of water were varied to find the effect of the parameters on foam generation. Research result showed that expansion ratio of foam was increased with wind flow rate. The expansion ratio of foam in the perforated type standard screen was higher than the wire mesh screen. Expansion ratio and drainage time were increased with increase of foam solution concentration. But a increase of salt concentration in solution showed the decrease of expansion ratio and drainage time.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.33 no.8
• /
• pp.92-98
• /
• 2005

Screen can provide any disturbed resistance that affects the change in characteristics of turbulence, velocity and pressure distributions of the flow field, and thus it has been widely used to control the flow. Some previous related studies for compressible flows have limitations such as, considering relatively low-Mach-number flows in the range of 0.3 ∼ 0.7, and not observing the detailed shock structures of the flow fields. An experimental study on highly compressible axi-symmetric supersonic jet flow fields behind wire-gauze screen has thus been carried out. Continuous/instantaneous flow images by Schlieren flow- visualization technique and the information of Pitot pressure/flow-noise measurements of the flow field behind the screen for various jet expansion conditions have been obtained. Effects of various porosity and inclination angles of the screen at the nozzle exit have also been investigated, and the experimental results have been compared to the case with no screen installed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2009.10a
• /
• pp.229-230
• /
• 2009

A method is suggested for the noise source identification using the sound intensity method. The suggested method does not need to install the grid using wire or thread during the sound intensity measurement for the noise source identification. It utilizes a camera to show the grid on the screen not installing the real grid for the sound intensity method.

• Journal of Biosystems Engineering
• /
• v.30 no.4 s.111
• /
• pp.202-209
• /
• 2005

The output of Stirling engine is influenced by the regenerator effectiveness. The regenerator effectiveness is influenced by heat transfer and flow friction loss of the regenerator matrix. In this paper, in order to provide a basic data for the design of regenerator matrix, characteristics of heat transfer and flow friction loss were investigated by a packed method of matrix in the oscillating flow as the same condition of operation in a Stirling engine. As matrices, 6 kinds of steel wires, 4 kinds of combined steel wires, 8 kinds of combined steel wires with screen meshes were used. The results are summarized as follows; Among 6 kinds of steel wires $({\phi}0.7\;mm,\;{\phi}0.9\;mm,\;{\phi}1.2\;mm,\;{\phi}\;1.6\;mm,\;{\phi}2.0\;mm,\;{\phi}2.7\;mm),$ the two steel wires $({\phi}0.7\;mm,\;{\phi}0.9\;mm)$ showed the highest in effectiveness. Among 4 kinds of combined steel wires $({\phi}l.6-{\phi}l.2\;mm,\;{\phi}1.2-{\phi}l.6\;mm,\;{\phi}0.9-{\phi}l.2\;mm,\;{\phi}l.2-{\phi}0.9\;mm),\;the\;{\phi}1.2-{\phi}0.9\;mm$ showed the highest in effectiveness. Among 8 kinds of combined steel wires with screen meshes $(150-{\phi}0.9\;mm,\;150-{\phi}l.2\;mm,\;{\phi}0.9\;mm-150,\;{\phi}1.2\;mm-150,\;150-{\phi}0.9\;mm-150,\;150-{\phi}1.2\;mm-150,\;150-{\phi}l.6\;mm-150,\;150-{\phi}2.0\;mm-150),\;the\;{\phi}l.2\;mm-150$ showed the highest in effectiveness.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.8 no.2
• /
• pp.313-319
• /
• 2013

This study shows the results of safety analysis obtained from the three different wire rope connections in the RPSD (Rope Platform Screen Door) system, which are the rope connected at both ends, the ropes connected by a pulley at both ends, and the ropes connected by many pulleys at both ends. With a constant load applied, the displacements in the ropes connected by a pulley at both ends and the ropes connected by many pulleys at both ends are smaller than that in the rope connected at both ends. There are no any special different displacements between the ropes connected by a pulley at both ends and the ropes connected by many pulleys at both ends. The displacement in the wire rope diameter of 6mm is smallest of 4.83mm and the strains from the displacements in the ropes connected by a pulley at both ends and the ropes connected by many pulleys at both ends are very small.

• Journal of Radiation Protection and Research
• /
• v.41 no.3
• /
• pp.216-221
• /
• 2016

Background: Very fine radiation-induced aerosol particles are produced in intense radiation fields, such as high-intensity accelerator rooms and containment vessels such as those in the Fukushima Daiichi nuclear power plant (FDNPP). Size measurement of the aerosol particles is very important for understanding the behavior of radioactive aerosols released in the FDNPP accident and radiation safety in high-energy accelerators. Materials and Methods: A combined technique using wire screens and imaging plates was developed for size measurement of fine radioactive aerosol particles smaller than 100 nm in diameter. This technique was applied to the radiation field of a proton accelerator room, in which radioactive atoms produced in air during machine operation are incorporated into radiation-induced aerosol particles. The size of $^{11}C$-bearing aerosol particles was analyzed using the wire screen technique in distinction from other positron emitters in combination with a radioactive decay analysis. Results and Discussion: The size distribution for $^{11}C$-bearing aerosol particles was found to be ca. $70{\mu}m$ in geometric mean diameter. The size was similar to that for $^7Be$-bearing particles obtained by a Ge detector measurement, and was slightly larger than the number-based size distribution measured with a scanning mobility particle sizer. Conclusion: The particle size measuring method using wire screens and imaging plates was successfully applied to the fine aerosol particles produced in an intense radiation field of a proton accelerator. This technique is applicable to size measurement of radioactive aerosol particles produced in the intense radiation fields of radiation facilities.

• Journal of Mechanical Science and Technology
• /
• v.14 no.1
• /
• pp.121-129
• /
• 2000

The thermal performance of a flat evaporator for capillary pumped loop (CPL) applications was investigated. Two to four layers of coarse wire screen wicks were placed onto the heated surface to provide irregular passages for vapor flow. The evaporator and condenser were separated by a distance of 1.2 m and connected by individual liquid and vapor lines. The wall material was copper and the working fluid was ethanol. The experimental facility utilized a combination of capillary and gravitational forces for liquid return, and distribution over the evaporator surface. The tubing used for vapor and liquid lines was 9.35 mm or less in diameter and heat was removed from the condenser by convection of air. A heat flux of up to $4.9{\times}10^4$ $W/m^2$ was applied to a flat evaporator having dimensions of 100 mm by 200 mm, 20 mm thick. The thermal resistance of the system as well as the temperature characteristics of the system was investigated as the evaporator heat flux and the condenser cooling capacity varied. The performance of the evaporator and effect of condenser cooling capacity were analyzed and discussed.

• Journal of Korean Society on Water Environment
• /
• v.30 no.5
• /
• pp.477-485
• /
• 2014

Imha Reservoir is connected to Andong Reservoir via a diversion tunnel allowing water to pass between. The diversion tunnel is equipped with screens to exclude exotic largemouth bass due to their predatory impacts on prey assemblages resulting in a degradation of species richness of local fish fauna and extinction of local fish populations in Korea. Flow pattern changes resulting from the fish screens and trash racks were investigated using a computational fluid dynamics (CFD) model. Numerical simulations showed that the decrease in the discharge capacity of the tunnel is approximately 8.6% and the headloss coefficient for fish screen at Andong intake tower was determined to be 1.5. In order not to allow the small fishes enough to pass through the wire openings enter into Imha Reservoir through tunnel, the velocity in the tunnel should be greater than 1.48 m/s which is a critical ascending velocity of the bass. This study suggests that it can keep the velocity higher enough to exclude largemouth bass when a gate opens with the condition of 1.0m difference in water stage between two reservoirs.

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