• Food Science and Biotechnology
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• v.16 no.4
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• pp.600-604
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• 2007

In this study, we first prepared 3 kinds of powders with different molecular masses from the crude protein-bound polysaccharide extract of Agraricus blazei Murill through ultrafiltration, followed by spray-drying. Then, the antitumor activities of the powders were analyzed. Size exclusion chromatography coupled with a multi-angle laser-light-scattering system showed the 3 powders had the following molecular ranges: below 10 kDa (SD-1), 10 to 150 kDa (SD-2), and above 150 kDa (SD-3), representing peak molecular weights of $8.26{\times}10^3,\;9.65{\times}10^4$, and $5.94{\times}10^6\;g/mol$, respectively. All the powders stimulated macrophage RAW264.7 cells to produce nitric oxide, of which SD-2 and SD-3 were superior to the crude extract powder (CP-SD), while SD-1 showed the lowest activity. Similar results were found for their cytotoxicities against human cancer cell lines (A549, MCF-7, and AGS), where the highest activity was obtained with the SD-2 treatment for 72 hr at $1,000\;{\mu}g/mL$. The MCF-7 cell line was less sensitive to the powders than the other cells. From this research we found that ultrafiltration, in combination with spray-drying, is applicable for preparing protein-bound polysaccharide powders with higher antitumor activities.

• Journal of the Korea Institute of Building Construction
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• v.4 no.1
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• pp.97-103
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• 2004

In case of a fire in road or railway tunnel it is always necessary to keep the escape condition as good as possible. Most of the victims of major fires in tunnels are because they couldn't leave the tunnel in time and were trapped by smoke, or rescue teams couldn't reach the place of the accident due to low visibility and high temperature. In spring 2003 a comprehensive field experiment was undertaken in a large scaled tunnel in Youngin City to test the effectiveness of a new water spray curtain system, designed to the air qualify inside of a tunnel in case of fire during passenger's escape to safe routes, In order to control the smoke propagation, fixed water sprayed nozzles were used to make water curtain system, which can be installed or hanging water piping line below ceiling. The experiment was accompanied by an extensive measurement campaign in order to measure temperature dropping effect and flow conditions as well as CO concentration for various water sprayed curtains produced by sprinkler heads or water spray nozzle. Eventually comparison analysis were undertaken to investigate the performance of water curtains under fixed water pressure. Therefore most effective water curtain system was presented on the basis of water droplet size in long tunnel.

• Corrosion Science and Technology
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• v.17 no.2
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• pp.74-80
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• 2018

The electronic industries require environmentally-friendly and highly functional materials to enhance the quality of human life. Home appliances require insect repellent steels that work to protect household microwave ovens from incurring damage by insects such as fire ants and cockroaches in tropical regions. Thus, POSCO has developed new types of functional steels, coated with an array of organic-inorganic hybrid composites on the steel surface, to cover panels in microwave ovens and refrigerators. The composite solution uses a fine dispersion of hybrid solution with polymeric resin, inorganic and a pyrethroid additive in aqueous media. The hybrid composite solution coats the steel surface, by using a roll coater and is cured using an induction curing furnace on both the continuous galvanizing line and the electro-galvanizing line. The new steels were evaluated for quality performances, salt spray test for corrosion resistance and biological performance for both insect repellent and antimicrobial activity. The new steels with organic-inorganic composite coating exhibit extraordinarily biological functionalities, for both insect repellent and antimicrobial activities for short and long term tests. The composite-coating solution and experimental results are discussed and suggest that the molecular level dispersion of insecticide on the coating layer is key to biological functional performances.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.5
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• pp.319-324
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• 2005

This study was conducted to identify the soluble carbohydrates in soybean seeds using on-line HPLC-RID-ES/MS and HPLC behavior, and to deter­mine their contents for high quality soybean breeding. The monosaccharide (glucose) and three oligosaccharides (sucrose, raffinose, and stachyose) were identified in Korean soybeans by their chromatographic behavior and results of on-line HPLC-RID-MS with Electro­spray Ionization mode. On the basis of HPLC with a RID detector, the 32 Korean major soybeans contain $0.37{\pm}0.26\%$ glucose, $4.55{\pm}0.91\%$ sucrose, $1.19{\pm}0.19\%$ raffinose, and $2.72{\pm}0.37\%$ stachyose on a dry basis. In 468 soybean germplasms, the ranges of glucose, sucrose, raffinose, and stachyose were $0.03 - 0.98\%$, $2.33 - 6.96\%$, $0.08 -1.87\%$ and $0.75 - 3.18\%$, respectively. Among 500 soybean samples, oligosaccharide contents of 32 Korean major cultivated soybeans and 468 soybean germplasms were varied $5.83 - 10.06\%$ and $3.66 - 10.32\%$, respectively. The composition of glucose, sucrose, raffinose, and stachyose in soluble carbo­hydrates of 500 soybean samples were $2.07 {\pm} 1.75\%$, $58.01{\pm}5.82\%$, $10.13{\pm}2.28\%$ and $29.80{\pm}4.54\%$, respectively. Sucrose appeared to be most prevalent in soy­bean soluble carbohydrates.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.585-591
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• 2013

A robot automation system for coating uniformly a big radiator used in PPS(Packaged Power Station), which consists of 6-axis robot with spray gun, travelling vehicle, supply device of coating paint and thinner with pressured air, HMI controller and robot path OLP(Off-Line Programming), was developed. Experimental results on an optimum operation condition show that a coating thickness is $43{\mu}m$, which is satisfied to a design reference of $25-100{\mu}m$. A productivity of the developed coating robot automation system based on OLP is about 12.6 times of that of manual operation.

• Journal of ILASS-Korea
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• v.2 no.4
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• pp.29-35
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• 1997

Liquid film thickness is measured by $moir\acute{e}$ topography which monitored liquid surface. $Moir\acute{e}$ fringe measurement techniques share the inherent simplicity found in optical interferometric techniques have the advantage of use over a greater range of displacement. $Moir\acute{e}$ fringe are the geometric interference patterns observed when two dense line grating are superposed. Light transmitted through a fixed line grating is deviated by the liquid film surface, producing a distored image of the grating. The $moir\acute{e}$ fringe produced by projection of this optically distored grating onto a second stationary grating permit visualization of the liquid surface and measurement of the liquid film thickness. This study measured the small amplitude of liquid film thickness to the $moir\acute{e}$ fringe pattern produced when spherical metal was dropped glycerin put)1 And the measurement of liquid film thickness flowing down an inclined plate are required to calculate the liquid slope in a position.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.3
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• pp.455-462
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• 2023

In this study, an automatic spraying lubrication system was developed to maintain the cleanliness of the switchgear when detecting the movement of the track through the switchgear. To develop this system, an air tank, valve block, and spray nozzle were designed, and the safety was secured through the pressure test of the prototype after designing the air tank. Furthermore, the environmental aspect was considered by minimizing the use of lubricant by enabling the mixing of air and lubricant through the production of a valve using the Venturi principle. The performance evaluation was conducted by implementing (producing) the injection system, and the product developed in this study was deemed installable in actual switchgear. It is expected that the proposed system will enable the maintenance of the cleanliness of the track during switching and reduce faults and malfunctions caused by switchgear defects.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.2
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• pp.95-102
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• 2001

In general there are many degrees of freedom(DOFs) in industrial robots. So they have many poses of several special end-effectors positions and orientations. For that reason, industrial robots are used in a wide scope of industrial applica-tions such as welding, spray painting, deburring, and so on. In this research, an off-line continuous path planning method based on linear interpolation with parabolic blend is developed. The method safely maintains the constant orientation for base frame and end-effectors path within allowable error and minimizes the number of segments in path. This algorithm may apply to welding and painting in which the orientation is particularly significant. The simulation study of cartesian curve is carried out to show the performance of this algorithm.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.22-26
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• 1999

In general, three are many degrees of freedom (DOF) in industrial robots. That can generate several special end-effector's positions and orientations. For that reason, industrial robots are used in a wide scope of industrial applications such as welding, spray painting, deburring, and so on. In this research, new method is presented which safely maintain the desired constant end-effector's orientation and minimize the numbers of segments in path. These algorithms may apply to welding, painting, and assembling. The simulation study of straight line and circular motions in arc-welding operations is carried out to show the sure proof of these algorithms.

• Journal of ILASS-Korea
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• v.9 no.4
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• pp.67-76
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• 2004

Diode laser absorption sensors are advantageous because they may provide fast, sensitive, absolute, and selective measurements of species concentration. These systems are very attractive for practical applications owing to its compactness, reasonable cost, robustness, and ease of use. In addition, diode lasers we fiber-optic compatible and thus enable simultaneous measurements of multiple species along a line-of-sight. Recent advances of room-temperature, near-IR and visible diode laser sources for telecommunication, optical data storage applications make it possible to be applied for combustion diagnostics based on diode laser absorption spectroscopy. Therefore, combined with fiber-optics and high sensitive detection strategies, compact and portable sensor systems are now appearing for variety of applications. The objectives of this research are to develop new gas sensing system and to verify feasibility of this system. Wavelength modulation spectroscopy has been demonstrated in these experiments and has a bright prospect to this diode laser system.