• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.2
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• pp.247-258
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• 2014

To evaluate the influence of the external force components on the littoral currents in the Gusipo beach, Jeonbuk, West Coast of Korea where a wide tidal sand flat developed, a coupled hydrodynamic model considered real time tidal currents and wave-induced currents was constructed in which the EFDC for tides and tidal currents, the SWAN for waves and the SHORECIRC for wave-induced currents were used as the hindcasting models. A series of field observations for tides, tidal currents and incident waves were carried out and especially to observe the littoral currents in the tidal sand flat, the GPS mounted and light weight drogues were used. Also wind data were collected from the adjacent weather station. To analyze the littoral current components, the numerical drogue tracking results considered real time winds, tides and waves were compared with the field drogue data. The drift speed of numerical drogues was reproduced as the range of 68.0~105.2% compared with the field data and the velocity error of main direction component showed a good result as -16.7~10.0%. As a result, in the mild slope tidal flat including wide surf zone, the tides and winds were the major affection component of the littoral currents, on the other hand, the wave-induced currents seemed the minor component when the incident wave heights were relatively small.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.4
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• pp.7-12
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• 1982

Growth of soybean sprouts(Glycine Max L.) and amounts of some chemical components were measured when they were exposed to blue light (120lux, 3hrs/day) during their growth. Hypocotyl length of irradiated soybean sprouts exceeded slightly that of control (dark) soybean sprouts, but the tfresh weight of whole sprouts as well as each part of the sprout showed no difference between the two groups. Chlorophyll content of cotyledon under blue light increased significantly with the lapse of days (3.57 and $8.45\;{\mu}g/100g$ fresh weight on the 3rd and 7th day). Bluelight irradiated sprouts contained more vitamin C than control sprouts (21.7% and 30.8% higher for the cotyledon and hypocotyl). Total amount of protein was not affected. Hypocotyl protein content was 8% of that in original soybean. Blue light did not affect the activity of trypsin inhibitor of sprouts. Similar activity of the inhibitor was observed in the cotyledon whereas hypocotyl showed activity corresponding to 23.7% of original bean. Polyacrylamide gel electrophoretogram for the protein showed 10, 9, and 11 bands in the original bean. 5th day cotyledon and hypocotyl respectively. Especially, band 3 of low Rm value was major protein component for the hypocotyl. Band 5 and 11 could be seen only in the protein of hypocotyl from bluelight irradiated sprouts, whereas no effect of blue light on the electrophoretogram was observed for the cotyledon.

• Korean Journal of Poultry Science
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• v.47 no.3
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• pp.159-167
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• 2020

This study investigated the effect of different light sources in the poultry house on performance, meat quality, and blood composition of finishing broilers. Two hundred and forty male broilers (1-day-old, 42.2±0.1 g) were divided into three groups and subjected to different light source treatments (incandescent, LED, and fluorescent lamps) from 3 weeks of age (four replications/treatment, 20 birds/replication). After breeding for 6 weeks, the carcass yield and meat quality of broilers with similar body weight (BW; 3.4±0.07 kg) were investigated, and blood components were analyzed. Corn-soybean meal-based feed was provided as starter (CP 22.5%, ME 3,020 kcal/kg), early (CP 18.5%, ME 3,050 kcal/kg), and finishing (CP 18%, ME 3,100 kcal/kg). Performance, carcass yield, meat quality, and blood components were evaluated. BW, BW gain, feed intake, and feed conversion ratio did not show any significant differences among treatments. There was no significant difference on live weight and carcass yield among treatments. There was no significant difference on meat color, shear force, and water holding capacity; however, cooking loss at 17.2% was the highest in the LED treatment (P<0.05). There was no significant difference on blood components except for glucose (blood biochemistry component) among treatments. Glucose was 234.5 mg/dL, 256.9 mg/dL, and 250.1 mg/dL in the three treatments, respectively, with a significant difference between incandescent and LED treatments (P<0.05). These results are used useful as basic data for investigating the effect of lighting in broilers production.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.5
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• pp.543-550
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• 2007

As an emerging materials in construction fields, FRP(fiber reinforced polymer) has been used in many area of civil engineering for its light weight and high strength. In this study we chose the 2nd Jindo-Bridge as a prototype, and evaluate effect of replacing steel components to FRP components through simplified 3D linear analysis. Static and modal analysis are done and the analysis results are compared with steel case analysis. From the static analysis results, the maximum stress of each component and maximum displacement of middle span are compared. Due to the reduction of deadload, the FRP structure causes less deflection than the original steel structure and from the reduced section (cable) analysis we confirmed the previous result. The occurrence wind velocity of flutter is compared by the frequency ratio.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.1
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• pp.68-74
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• 2003

This paper describes the design and the test results of the receiver-downconverter module for a Ka-band Satellite Payload. The developed module is not only a downconverter that convert the signal of 30.6 GHz∼31.0 GHz to the signal of 20.8 GHz∼21.2 GHz but also is a receiver that has the function of low noise amplification in the front stage. It has been fabricated and tested by the qualified satellite component manufacturing process and it shows the best performance of the receiver-downconverter modules operating at Ka-band frequency up to date. The module has the performance of 1.9 dB-NF, 55 dB-Gain, and 58 dBc-C/I3 fur the two tone signals of -59 dBm input power respectively at ambient temperature. It is a small and light module with the size of 93 mm${\times}$84 mm${\times}$26 mm and the weight of 240 g.

• Journal of the Korean Society of Radiology
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• v.12 no.5
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• pp.693-698
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• 2018

Currently, shields for shielding medical radiation during medical examinations in the medical environment are lead robe and lead glass. Lead, the main component of this shielding, has limitations in lead poisoning and light weight, and high price. Iodine, which is used as contrast medium instead of lead shield, is expected to be effective as a shield because it has radiation absorbing properties. The purpose of this study was to evaluate the effectiveness of shielding by using acrylic plate filled with CT contrast agent for clinical use instead of conventional lead glass. As a result, it was found that the acrylic plate filled with the CT contrast agent showed a shielding effect of 7 times or more when the scattering ray dose was not shielded. Therefore, CT contrast agent composed of iodine is expected to be used as a shield instead of conventional lead glass.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.2
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• pp.143-148
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• 2007

An impulse turbine, which is a main component of a liquid rocket engine, needs to be a small size with light weight and generate large power. Since the impulse turbine is being operated under complicated supersonic conditions, flow analysis and performance prediction largely depend on CFD technique. In order to increase the reliability of the prediction code, however, it often requires an experimental data to compare. In this research a rotating turbine rotor with multiple blades is simulated with a two-dimensional stationary cascade to check the effect of major flow parameters. Mach number is measured at nozzle exit by using a pitot tube and the blade thrust was also measured with a load cell. The measured thrust coefficient and the power are compared well with the designed conditions, which proves the design procedures are properly taken.

• Journal of Ocean Engineering and Technology
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• v.24 no.6
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• pp.76-80
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• 2010

Oil hydraulic piston pumps are being extensively used around the world, because of their simple design, light weight, effective cost, etc. An oil hydraulic pump is likely to have the serious problems of high leakage, friction, and low energy efficiency after a long period of use. In an oil hydraulic piston pump, the clearance between the valve block and piston plays an important role for volumetric and overall efficiency. In this study, the wear property of the SACM645 material with DLC coating used for a hydraulic piston pump was determined by experimentation with variable heat treatment. To investigate the effect according to the piston surface condition, five different types of specimens were prepared. The maximum tensile strengths of the QT and QT Nitration specimens had similar values of about 800 MPa, but the strains indicated a big difference. In a wear test, the wear characteristic of the DLC coating specimen was shown to be excellent. The QT, QT + IH, QT + Nitration, and matirx specimen showed similar wear characteristics. In the case of a dry condition without oil, the DLC coating specimen had good wear resistance, with no wear shown.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.305-308
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• 2006

Advanced mobile communication devices require a bright, high information content display in a small, light-weight, low power consumption package. For portable applications flexible (or conformable) and rugged displays will be the future. In this paper we outline our progress towards developing such a low power consumption active-matrix flexible OLED $(FOLED^{TM})$ display. We demonstrate full color 100 ppi QVGA active matrix OLED displays on flexible stainless steel substrates. Our work in this area is focused on integrating three critical enabling technologies. The first technology component is based on UDC's high efficiency long-lived phosphorescent OLED $(PHOLED^{TM})$ device technology, which has now been commercially demonstrated as meeting the low power consumption performance requirements for mobile display applications. Secondly, is the development of flexible active-matrix backplanes, and for this our team are employing PARC's Excimer Laser Annealed (ELA) poly-Si TFTs formed on metal foil substrates as this approach represents an attractive alternative to fabricating poly-Si TFTs on plastic for the realization of first generation flexible active matrix OLED displays. Unlike most plastics, metal foil substrates can withstand a large thermal load and do not require a moisture and oxygen permeation barrier. Thirdly, the key to reliable operation is to ensure that the organic materials are fully encapsulated in a package designed for repetitive flexing, and in this device we employ a multilayer thin film Barix encapsulation technology in collaboration with Vitex systems. Drive electronics and mechanical packaging are provided by L3 Displays.

• Journal of Fashion Business
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• v.19 no.4
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• pp.120-134
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• 2015

This study aimed to determine the physical properties of silk and nylon fabrics that are treated with persimmon juice in accordance with irradiation time of ultraviolet spectrum. Persimmon juice dyeing has the advantage of using the tannin component of the persimmon. Tannin plays an important role in inhibiting photodegradation of fibers or polymers. Among fibrous materials, silk and nylon are prone to deterioration by light. Hence, this study aimed to reduce these weaknesses of silk and nylon by applying persimmon juice treatment. We accordingly carried out investigation and experiments on ultraviolet irradiation, and physical characteristics of treated fabrics. The persimmon juice treatment process led to increased weight and thickness. In addition, the air permeability of silk fabric was increased, as compared to the control specimen; whereas, that of nylon fabric was decreased. Both drape stiffness and flex stiffness of silk and nylon tended to be high in textiles processed with persimmon juice treatment, as compared to the control textile. Peak load and elongation at peak load of untreated samples clearly decreased in both silk and nylon fabrics with the increase of ultraviolet irradiation time, while those of persimmon juice treated samples increased. Furthermore, ultraviolet blocking ratio measurement indicated that the fabric specimens treated with persimmon juice blocked U.V. spectrum better than the control specimen.