• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1631-1633
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• 2005

This paper describes the measurement result of leakage current flowing arrestors connected in catenary line to propose an optimal management methods. 27 arrestors set in 7 locations were tested. The leakage currents are included a harmonics of electric train during the operation of electric train in feeding section and in case of feeding earthing system.

• Fisheries and Aquatic Sciences
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• v.24 no.6
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• pp.219-227
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• 2021

The effects of various feeding ratios on the growth, body composition, and blood chemistry of the juvenile mandarin fish Siniperca scherzeri (initial body weight 9.6 g) were examined in recirculating freshwater system equipped with 21, 300 L tanks at 20 fish per tank. The triplicate groups of seven feeding ratios treatments were prepared: 100% (control), 95%, 90%, 85%, 80%, 75%, and 70% of satiation. The feed amount of control group was determined by supplying with apparent satiation and then the feed amounts of the other six feeding groups were determined based on the feed amount of the control group. Fish were hand-fed with test diet (55.4% crude protein) for 10 weeks. Weight gain (WG) and specific growth rate of fish fed to 100% satiation were not significantly (p > 0.05) different from those of fish fed to ≥ 80% satiation but were significantly higher than those of fish fed to 75% and 70% satiation. Feed efficiency, protein efficiency ratio, and protein retention of 100% satiation were not significantly different from those of 95% and 90% satiation but were significantly (p <0.05) lower than ≤ 85% satiation. Condition factor, hepatosomatic index, and coefficient variation were not significantly (p > 0.05) affected by feeding ratio. Whole body composition and contents of hematocrit, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, glucose, total protein, and high-density lipoprotein cholesterol in blood serum were not significantly (p > 0.05) affected by the feeding ratio; however, content of total cholesterol tended to decrease as the feeding ratio decreased. Using broken-line analysis of WG, it was suggested that the optimum feeding ratio of juvenile mandarin fish, ranging from 9.0 g to 37.0 g, appeared to be 87.7% of satiation without growth inhibition.

• Journal of Aquaculture
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• v.21 no.4
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• pp.244-251
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• 2008

We evaluated the optimum dietary lipid level and feeding rates of extruded pellets (EP) in juvenile flounder Paralichthys olivaceus during the summer season. The first experiment was conducted to determine the optimum dietary lipid level in juvenile flounder. Five isonitrogenous EP (52% crude protein) with increasing dietary lipids (6, 8, 10, 12 and 14%) were fed to satiety to triplicate groups of the juveniles ($18.4{\pm}0.11g$) twice a day for 6 weeks. Weight gain (WG) of fish fed EP with 10% lipid was significantly higher than those of fish fed EP with 6 and 14% lipid (P<0.05). Broken line model analysis suggested that the optimum dietary lipid level could be $9.08{\pm}0.37%$ for the maximum WG in juvenile flounder. The second experiment was conducted to determine the optimum feeding rate using experimental diet contained 10% lipid level that had the highest WG in first experiment. The feed intake of triplicate groups of the juveniles ($13.4{\pm}0.15g$) was restricted to four different feeding rates of 2.0, 2.5, 3.0 and 3.5% of their body weight $day^{-1}$ and to satiation using experimental diets. WG and feed efficiency (FE) of fish was affected by feeding rates. WG and specific growth rate of fish fed the diets increased with increasing feeding rate, however no significant differences (P>0.05) in WG and specific growth rate were observed between the fish fed 3.5% of their body weight $day^{-1}$ and to satiation. FE of fish fed 3.5% of their body weight $day^{-1}$ was significantly higher than those offish fed 2.0% of their body weight $day^{-1}$ and to satiation (P<0.05). Broken line model analysis suggested that the optimum dietary feeding rate could be $3.56{\pm}0.06%$ for the maximum WG in juvenile flounder. These results indicated that the optimum lipid level and feeding rate could be $9{\sim}10%$ (Energy: 4,774kcal and PIE ratio: 108mg protein/kcal in diet) and 3.5% of their body weight $day^{-1}$in juvenile flounder, respectively.

• Journal of Electrical Engineering and Technology
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• v.11 no.5
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• pp.1305-1310
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• 2016

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.2
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• pp.570-580
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• 2017

In this study, we designed a fishing system to reproduce the underwater movement of the living Sword tip squid (Loligo edulis) used as bait in the red seabream long line fishery, and conducted the experiment of the fishing operation in 2 ways, i.e., a pole and line fishing method (fishermen) and a bait control fishing system used at fishing sites. Based on the catches in fishing operation, the experiment was conducted over a six times (2014 & 2015), and then 107 fishes were caught by the line fishing method while 57 fishes were caught by the bait control fishing system. The fishermen method actively controlled the speed of gear movement upward and downward while checking the reaction of red seabreams to the bite in the process which a jerk was transmitted to single line hook fishing gear manually. The bait control fishing system is a passive method which fishermen visually check only the movements at the end of fishing pole, enabled differentiation of bite reactions of red seabream during fishing operation. Thus, the difference between fishermen method and the bait control fishing system was found to about 53.3% in the catches. We confirmed the possibility of a site fishing operation based on the bait control fishing system designed newly as a result of this study. Improvement is in several areas for commercialization at the site. This fishing system is expected to be able to find wide-ranging applications as a new labor-saving method for the fishing red seabreams if it is applied to the fishing sites after aforesaid process.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.2
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• pp.9-17
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• 2007

The performance test of recirculation line in propellant feeding system was carried out. Liquid oxygen was used as cryogenic propellant and helium was used as recirculation promotion gas. Tests were done in cases at atmospheric pressure and at pressure of 4 barg in the ullage space of propellant tank. Liquid oxygen recirculation flowrate with helium injection flowrate and temperature distribution along the line were measured. There was appropriate helium injection flowrate for gas-lift recirculation system. Test data were used to make calculation program by test data correlation method. In this paper the procedure of calculation was presented and the results were compared to test data.

• Journal of the Korean Society for Railway
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• v.15 no.4
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• pp.357-363
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• 2012

This paper presents a new operation method for the single phase PWM(Pulse Width Modulation) converter train. Recently, the trains adopting the PWM converter have become the majority in the electric locomotives since there are distinct advantages over the predecessors, which can be operated at near unity power factor. However, a slight modification of the control scheme makes this kind of vehicles run in the region of leading power factor. Although this feature seems to be of no significant use by itself, the leading phase operation can improve the voltage profile and the line loss of the feeding systems is decreased by compensating the reactive power loss along the line when it considered together with the feeding systems. This method is even more economical and efficient comparing with the installation of SVC that is mainly used for this purpose since the train can become a movable compensator. With the conditions and some essential formula for the leading phase operation, a new power factor control algorithm has been proposed to implement this scheme. The results of simulation through SIMULINK model show that the proposed method is suitable enough for practical use.

• Korean Journal of Ichthyology
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• v.24 no.4
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• pp.247-252
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• 2012

Structure on the feeding organs in two Korean ricefishes, Oryzias latipes and O. sinensis, was examined in the jaws and the teeth. In the jaw, O. latipes has a dent on the dorsal edge of distal arm of premaxilla (vs. straight in O. sinensis) and a alveolar arm of premaxilla running in straight line with distal arm of premaxilla (vs. ventra line in O. sinensis). O. latipes has also a dent on the posterior edge of dentary which is connected to coronoid process of dentary (vs. straight in O. sinensis). Large teeth developing only in the male, which is sexual dimorphism, developed into outside direction of the mandible in O. latipes (vs. dorsal direction in O. sinensis). In the teeth forms, O. latipes has two types (conical type and arrowhead type), whereas O. sinensis has only one type (conical type). Through this study, we confirmed that two Korean ricefishes show distinctive characteristics in the structure of the feeding organs.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1069-1070
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• 2008

At the coupling area linking high speed line and conventional line, according to distance between trains due to speed limit of conventional line, the power load of substation supplying to this conventional line increase. At the coupling area between Kimcheon SS and Kyoungsan SS, train operation have problems caused by instantaneous voltage drop. So, this paper propose evaluation method of maximum load capacity at current normal feeding condition.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.3
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• pp.257-262
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• 2002

A single-layered radial line slot array (SL-RLSA) antenna etched on a substrate and fad by a rectangular waveguide is presented in the 60 ㎓ band. The design curves are obtained by an efficient electromagnetic coupling analysis using Ewald Sum technique and Shanks transformation. The antenna has rectangular waveguide feed structure using a rectangular waveguide-to-radial line transition. The prototype antenna of 10 cm-diameter was tested and the gain of 31 ㏈i and the efficiency of 38% were measured at 60 ㎓.