• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.222-225
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• 1999

This paper presents the surges response of the grounding systems using frequency domain electromagnetic field analysis software package. The frequency and time domain performance of a building grounding systems subjected to a lighting strike is described and discussed. The computed scalar potentials is presented graphically as a function of spatial coordinates. A double exponential lighting surge current is injected at one corner or the building grounding systems. Time-variant response of rod, mesh and kit grounding systems under impulse currents have been obtained. This paper deals with the results of studies on the time variation of ground resistance in three grounding systems.

• Korean journal of food and cookery science
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• v.7 no.4
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• pp.9-13
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• 1991

Nochi is a kind of Korean traditional food made from glutinous rice or millet. This study attempted to examine the effects o( the various factors and to clarify the factors which affect the overall eating quality of Noch. The results were summarized as follows. 1. Starch content of waxy rice was 72.4% and IBC was 0.017%. 2. $\alpha$-amylase and $\beta$-amylase activity of malt were 40.13 and 8.94 units respectively. 3. Waxy rice soaked for 3 hours was ground to flour then sifted 20 mesh sieve. The mixture of waxy rice and malt was steamed for 20 minutes. 4. In sensory evaluation on varying the amount of malt and incubation time, the most favorite tendancy of the overall eating quality was at the level of 8hours incubation made by 5% addition of malt. 5. Total sugar contents, reducing sugar contents and the intensities of iodine stain at the incubation temperature of $60^{\circ}C$ were significantly different from those at $50^{\circ}C$.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.68 no.5
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• pp.656-661
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• 2019

Currently, the devices to generate ion winds in air are mainly composed of corona electrodes and induction(ground) electrodes, of which the corona electrodes mainly use needles or wires as electrodes and the induction electrodes use plate electrodes of ring or mesh type. Ion winds can be effectively generated through a diverse combination of corona electrodes and induction electrodes mentioned above. However, only changing the form and structure of corona electrodes and induction electrodes has a limit in raising the speed of ion winds. This paper conducted a study on the characteristics of ion wind generation by additionally installing acceleration electrodes in addition to corona electrodes and induction electrodes to increase the speed of ion winds.

• Food Science and Preservation
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• v.12 no.3
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• pp.204-208
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• 2005

This study was conducted to investigate the effects of temperature and packaging on the quality characteristics of hot-water extract from Acanthopanax senticosus. The herb samples, ground and sifted($8{\sim}20$ mesh), were extracted by a boiling($100^{\circ}C$) water under the atmospheric pressure for 2 hrs. The extract was packed with out nylon PE(0.08 mm) pouch and kept under the condition(40 and $60^{\circ}C$) for 10 days. The reduction of turbidity, pH, polyphenol amount and DPPH radical scavenging activity of extract were retarded by packaging under the low temperature. Titratable acidity was increased with packaging at high temperature. Soluble solid content was not affected by packaging and temperature condition. The changes of quality characteristics followed the first-order reaction rate. Arrhenius equation was applied to determine the effects of temperature on the reaction rate constant, showing high $R^2$. These results suggested that packaging under lower temperature can be utilized for maintaining the quality of A senticosus extract.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.702-706
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• 1996

Husked barley contained 17.2% dietary fiber and naked barley contained 14.9% dietary fiber. The barley was ground in a Udy cyclotec mill having a 0.5 mm screen and sieved with a 400-mesh screen (38 m openings). Coarse material of naked barley retained by the screen, with a weight yield of 54.1%, contained 7.0% soluble dietary fiber, 13.9% insoluble dietary filer and 20.9% total dietray fiber. As the naked barley flour level increased in bread baking, the water absorption, mixing time, and loaf weight increased, but the loaf volume decreased. Barley flour was added to wheat flour at a replacement level of 10% without a large adverse effect on bread quality, and the dietary fiber content of bread was increased from 3.0% to 5.0%. The soluble dietary fiber content was not changed, but the insoluble dietary fiber content was increased during the baking process.

• Food Science and Preservation
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• v.12 no.2
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• pp.146-150
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• 2005

A comparative study of pretreatment and extraction methods was conducted to investigate their effects on nutritional and bioactive components during hot-water extraction of Acanthopanax senticosus. The herb samples, ground and sifted $(8\~20\;mesh)$ were pretreated with ultrasound (20 kHz), microwave (2,450 MHz) or roasting $(180^{\circ}C)$ for 10 min, and then extracted by a boiling $(180^{\circ}C)$ under atmospheric pressure or a pressured boiling $(121^{\circ}C)$ for 2 hr. In general, the pretreatments improved the extraction efficiency and the DPPH radical scavenging activity of extract. Particularly, the extraction yields of soluble solids, total sugar and phenolic compounds were increased in microwaving methods, and the protein yield and the radical scavenging activity were higher in roosting pretreatment. Yields of soluble solids, total sugar, protein and phenolic compouds in pressured extraction were higher than those in nonpressured extraction. These results suggested that pretreatment including microwave radiation, sonication and roasting and pressured extraction can be utilized for improving the extraction efficiency of A. senticosus.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.3
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• pp.179-187
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• 2005

This study was conducted in order to the experiment of bottom trawl fisheries in the sea mount of central northern pacific($30^{\circ}-40^{\circ}N$, $170^{\circ}-175^{\circ}E$), during the period of July 1 to August 25, 2004 by commercial trawl ship. Fishing experiment was carried out by bottom trawl, with the codend of 110mm mesh size. The number of 101 test fishing was done in the sea mount of central northern pacific during 56 days and the total catches were 198,593kg as 18 fish species, and CPUE/day and catches/day were 8.3 hours towing time and 3,546kg. Catch ratio according to each fishing ground was higher with the order of B, C, and E, and catches for B was 7,171.0kg during the towing time of 13.2 hours. Main target species were Pseudopentaceros richardsoni and Beryx splendens, there was 14.9% of damage ratio for fishing gears on catching the target fishes inhabiting on the rough sea bottom. Catches by water depth was the order of 300m below, 301-350m, 451-500m and 351-400m. It is thought that there was no problem on the mesh size because most of fishes caught from the experimental fishing was 30cm over.

• Journal of the Korean Geotechnical Society
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• v.32 no.4
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• pp.29-39
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• 2016

This paper presents the results of 2D and 3D finite element simulations conducted to analyze the effects of excavation depth (H), excavation width (L), and ground condition on the behavior of anchored earth retaining wall in inclined ground layers. The results of numerical analyses are compared with those of the site instrumentation analyses. Based on the results obtained, it appeared that 2D numerical analysis tends to overestimate the horizontal displacement of retaining wall compared to the 3D numerical analysis. When the excavation depth is deeper than 20m, it is found that 2D and 3D numerical analysis results of excavation work in soil ground condition are more different from the results in rock ground condition. For an accurate 3D numerical analysis, applying 3D mesh which has an excavation width twice longer than excavation depth is recommended. Consequently, 3D numerical analysis may be able to offer significantly better predictions of movement than 2D analysis.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.6
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• pp.241-249
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• 2022

This paper discusses the design of a ground clutter prevention fence for a radar wind profiler (RWP). The design point of the clutter fence is to improve the quality of the received signal by removing the non-weather clutter coming from the side. In this paper, a clutter prevention fence composed of a metallash mesh around the RWP is proposed, and the phase center of the antenna, the length, and height of the down fence, and the height and slop of the top fence through M&S are designed. The designed ground clutter prevention fence and 256 active phase array antennas were used as basic data. The effectiveness of the design was confirmed by a simulation. The side lobe in the ±90° direction was reduced by more than 30dB depending on the presence or absence of the designed ground clutter prevention fence. The fence was manufactured by 3D modeling, and the clutter shielding performance of approximately 20dB or more on the side of the antenna (±90°) was confirmed by applying it to the currently operated RWP.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.185-185
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• 2011

Mapping of artificial levee lines, one of major tasks in river zone mapping, is critical to prevention of river flood, protection of environments and eco systems in river zones. Thus, mapping of artificial levee lines is essential for management and development of river zones. Coastal mapping including river zone mapping has been historically carried out using surveying technologies. Photogrammetry, one of the surveying technologies, is recently used technology for national river zone mapping in Korea. Airborne laser scanning has been used in most advanced countries for coastal mapping due to its ability to penetrate shallow water and its high vertical accuracy. Due to these advantages, use of LiDAR data in coastal mapping is efficient for monitoring and predicting significant topographic change in river zones. This paper introduces a method for construction of a 3D artificial levee line using a set of LiDAR points that uses normal vectors. Multiple steps are involved in this method. First, a 2.5-dimensional Delaunay triangle mesh is generated based on three nearest-neighbor points in the LiDAR data. Second, a median filtering is applied to minimize noise. Third, edge selection algorithms are applied to extract break edges from a Delaunay triangle mesh using two normal vectors. In this research, two methods for edge selection algorithms using hypothesis testing are used to extract break edges. Fourth, intersection edges which are extracted using both methods at the same range are selected as the intersection edge group. Fifth, among intersection edge group, some linear feature edges which are not suitable to compose a levee line are removed as much as possible considering vertical distance, slope and connectivity of an edge. Sixth, with all line segments which are suitable to constitute a levee line, one river levee line segment is connected to another river levee line segment with the end points of both river levee line segments located nearest horizontally and vertically to each other. After linkage of all the river levee line segments, the initial river levee line is generated. Since the initial river levee line consists of the LiDAR points, the pattern of the initial river levee line is being zigzag along the river levee. Thus, for the last step, a algorithm for smoothing the initial river levee line is applied to fit the initial river levee line into the reference line, and the final 3D river levee line is constructed. After the algorithm is completed, the proposed algorithm is applied to construct the 3D river levee line in Zng-San levee nearby Ham-Ahn Bo in Nak-Dong river. Statistical results show that the constructed river levee line generated using a proposed method has high accuracy in comparison to the ground truth. This paper shows that use of LiDAR data for construction of the 3D river levee line for river zone mapping is useful and efficient; and, as a result, it can be replaced with ground surveying method for construction of the 3D river levee line.