• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.30 no.2
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• pp.71-77
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• 1994

A serious of study is carried out to practical use of the three-slot cambered otter board improved by the authors. As the first step, we designed main plates, slots and accessories, such as holding plate, fan-shaped towing plate, normans, center ring, etc. Standing on this design, we made the simple cambered and three-slot cambered model otter board with accessories in a linear scale 6:1. and carried out model test to examine the efficiency of these boards. The obtained results can be summarized as follows: 1. On the simple cambered board with accessories, the values of the maximum shear coefficient($C _{LX}$ ). drag coefficient(($C _{D}$) and hydrodynamic efficiency($C _{L}$/$C _{D}$ ) are 1.39, 0.56, 2.48 at $22^{\circ}$ of the angle of stall respectively. 2. On the three-slot cambered board with accessories, $C _{LX}$/$C _{D}$ and $C _{I}$/$C _{D}$ are 1.67, 0.92, 1.82 at $32^{\circ}$ of the angle of stall respectively. 3.$C _{LX}$ of board with accessories is smaller 10~12% than that of only the main plate, and the angle of stall is almost same. 4. $C _{LX}$ and the angle of stall of the three-slot cambered board with accessories are greater 20% and $10^{\circ}$ than that of the simple cambered board respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.24 no.2
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• pp.78-82
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• 1988

Near sea trawlers of Korea sometimes catch pelagic fishes like file fish by using midwater trawl gear even though usually catch bottom fish. It is reasonable to use the specific otter board as well as specific net in bottom trawling and in midwater trawling respectively. But, the trawlers are so small ranging 100 to 120GT, 700 to 100ps that it is very complicated to use different otter board for bottom trawling and for midwater trawling. The otter board for bottom trawling. is also used for the midwater trawling without any change even though the net is changed into the specific one. Although the otter board in the midwater trawling should be lighter than that for bottom trawling, to use otter board for bottom trawling directly for the midwater trawling without any change makes the net easily touch the sea bed and also make the horizontal opening of the otter boards be limited owing to the length of warp in the southern sea of Korea, main fishing ground of midwater trawling, which is 100m or so in depth. That is why the otter board for the midwater trawling should be made lighter than that in the bottom trawling, even if temporary. The authors carried out an experiment to achieve this purpose by attaching a large styropol float on the top of the otter board. In this experiment, underwater weight of the otter board was 630kg and buoyancy of the float was 510kg. To determine the depth and horizontal opening of the otter board, two fish finder was used. A transmitter of 50KHz fish finder was set downward through the shoe plate of otter board to determine the elevation of otter board from the sea bed, and a transmitter of 200KHz fish finder was set sideways on the starboard otter board to be able to detect the distance between otter boards. The obtained results can be summarized as follows: 1. The actual towing speed in the experiment varied 1.1 to 1.8 m/sec. 2. The depth of otter board was within 41 to 25m with float on the top and 45 to 26m without float in case of the warp length 100m, whereas the depth 68-44m with float and 74-46m without float in case of the warp length 150m. This fact means that the depth with float was 9-4% shallower than that without float. 3. The horizontal opening between otter boards was within 34-41m with float and 30-38m without float in case of the warp length 100m, whereas the opening was 44-50m with float and 37-46m without float in case of the warp length 150m. This fact means the opening with float was 10% greater than that without float in case of the warp length 100m, and 15% greater in case of the warp length 150m. 4. The horizontal opening between wing tips by using the otter board with float was 1m greater than by without float in case of the warp length 100m, whereas the opening by with float was 2m greater than by without float in case of warp length 150m. From this fact, it can be estimated that the effective opening area of the net mouth by using the otter board with float could be made 10% greater than by without float in case of warp length 100m, whereas the area with float 20% greater than by without float in case of warp length 150m.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.06a
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• pp.33-44
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• 2001

The generally known vertical drain methods for improvement of soft ground are Sand Drain, Sand Compaction Pile, Plastic Drain Board, and Pack Drain. Recently, Plastic Drain Board method application in soft ground is widely used. In this case study, it is compared with each other vertical drain methods from the results of monitorning and test embankment. The results of the analysis and the study show that Plastic Drain Board method is relatively acceptable as vertical drain method.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.605-606
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• 2021

In this paper, one channel oscilloscope was implemented using arduino uno board and 1.8 inch TFT LCD. The oscilloscope is designed using the built-in analog to digital converter(ADC) inside arduino uno board as data acquisition unit and can handle up to about 1 KHz signal.

• Journal of the Korea Furniture Society
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• v.10 no.2
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• pp.17-27
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• 1999

As a countermeasure to reach self-sufficiency for wood supply and demand, we have to develop wood substitutes. Rice hull is the cheapest fiber material we can get in Korea, What is better the yield of rice hull amounts to 1 million tons per year. Before carrying out this study, new ecomaterial rice hull board for housing materials was developed successfully. In order to evaluate whether the rice hull board with or without bioceramic treatment is suitable for housing materials, we studied the environmental effect of the above materials in comparison with the polycarbonate, stainless, or concrete on the adaptation (body weight, water/feed consumption, general signs, urinalysis, autopsy, etc) and the reproduction(litter size, newborn adaptation, etc)of mice. In conclusion, the concrete cage was the worst in the adaptation and so was the stainless steel cage in the reproduction. The rice hull board cage with or without bioceramic treatment was superior or equivalent to other material cages from the standpoints of the adaptation and reproduction.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.10
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• pp.44-51
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• 2012

The purpose of this study is development of the diagnosis system to preventative maintenance in the on-board measuring systems for in-cab electric inspection systems of high speed railway. The on-board measuring systems can inspect precisely whether ground signal system operate stably. In this paper, we recognize characteristics of the track circuits and confirm whether the wave of current matches the on-board measuring data through the electric modeling method for high speed railway. it is necessary to develop GUI visual programs that can simulate abnormalities of the on-board measuring data in many ways, and the visual program is designed to diagnosis in the case of track circuit equipment's function decreased in advance.

• International Journal of Railway
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• v.5 no.2
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• pp.77-83
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• 2012

Railroad signaling systems are to control intervals and routes of trains. There are ATS, ATP, ATO and ATC system. Trains are operated in the section which is met on the signaling system because various signaling systems are used in Korea. Hence, trains are not operated in the section which is used in the other signaling system. To solve this problem, recently combined on-board system has been developed. The combined on-board system designed by doubling the ATS, ATP and ATC system to ensure the safety of system. The inductance of antenna is change and in return the resonance frequency of antenna is varied by the electromagnetic induction. Therefore, the information signal is not received exactly in the combined on-board system and in return accidents between trains occur. In this paper, electric model of the combined on-board system for considering the ATS and ATP antenna is presented. Moreover, the mutual inductance including the distance between the ATS and ATP antenna is calculated. As a result of the frequency response of the antennas, the mutual inductance met on operation range of resonance frequency is defined.

• Korean journal of food and cookery science
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• v.24 no.5
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• pp.706-712
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• 2008

This study was conducted to evaluate the sanitation level and use of dish cloths, chopping board, and drawer in the refrigerator in 50 university students' houses located in Seoul and Kyonggido. The survey questionnaire evaluated general information, frequency of the washing, cleaning method, drying method and the associated factors. The highest percentage of the cleaning and drying methods of dish cloths were “boiling(76.0%)”, and “dry in the kitchen or on the sink(78.0%)”, respectively. For the chopping board and drawer in the refrigerator, the highest percentage of cleaning method was “use detergent” and drying method was “dry in the kitchen”. The mean of coliforms for dish cloths, chopping board, and drawer in the refrigerator was 4.46${\pm}$1.95 log CFU/100 $cm^2$, 3.92${\pm}$1.64 log CFU/100 $cm^2$, 3.48${\pm}$2.01 log CFU/ 100 $cm^2$, respectively. Salmonella spp. were not detected from all samples. But E. coli were detected from dish cloths(4.0%) and S. aureus were detected from dish cloths(16.0%), chopping board(12.0%), and drawer in the refrigerator(8.0%). The results of microbiological test of kitchen utensils indicated that the sanitary conditions of dish cloths, chopping board, drawer in the refrigerator should be improve promptly.

• The Journal of Korean Society for Radiation Therapy
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• v.18 no.1
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• pp.43-51
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• 2006

Purpose: To resolution of A hospital-handmade modification double tilt angle immobilization system (DTAB immobilization system) and to report the clinical results of it. Material and Methods: It was developed in conjunction with the breast board for patients unable to achieve and maintain the desired uncomfortable respiration and position of set-up needed in the treatment of RT (This custom design provides an alternative to accomplishing this desired head angle needed to relax position treatment area, realizing that the lenses totally protected eye-ball out) By using the angled breast board and SBDD(small bowel device), reproducibility of set-up and patient comfort were addressed throughout the simulation, computed tomography planning and treatment process. Results: Usually patients the error range-within 5 mm. When use of Aqua patients error range-within 3 mm. Conclusion: It was constructed in tandem with a unique custom-built double tilt angle board (DTAB). It was designed to eliminate clinical set-up problems with head immobilization and instability during treatment, thus providing for a more comfortable head rest for the patient.

• Journal of agriculture & life science
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• v.46 no.1
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• pp.29-34
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• 2012

To examine possibilities to make use of woodceramics for the lower material of hot-floored ondol boards, woodceramics made from sawdust board with Pinus densiflora, put them in a wood frame and concrete block and heated them sending an electric current, and measured changes in surface temperature of a laminated floor board and a plywood floor board. As the sending an electric current to time passed, their surface temperature increased rapidly up to 20 minutes, and then gradually ascended. In terms of the surface temperature in the wood frame, the beginning temperature of a plywood floor board was higher than that of laminated floor one; however, as time passed, a laminated floor board's temperature rose, and after 60 minutes, it showed similar to the temperature of a floor board of lamination. On the other hand, the surface temperature in a concrete block showed that the laminated floor board was higher than the plywood floor board in both early and 60-minute later temperatures. With the lapse of time after switching off, the surface temperature of floor boards slowly dwindled up to 9 minutes, and from that time on, began to drop sharply. In terms of the descent speed of surface temperature, when woodceramics' surface temperature was adjusted at $70^{\circ}C$, the laminated floor board was the highest; when it was at $80^{\circ}C$, the plywood floor board was the highest, resulting in rapid descent speed of heat.