• Korean Journal of Environment and Ecology
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• v.33 no.2
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• pp.168-177
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• 2019

This study was conducted to examine the impact of various environmental factors on the feeding behavior of black-faced spoonbills Platalea minor known to use rice fields during the breeding season. We surveyed the rice fields three times a month from April to June 2017 and from April to June 2018. We counted the number of black-faced spoonbills and measured the environmental factors such as the water depth, paddy type by cultivation stage, and biomass of potential prey that are expected to affect black-faced spoonbills. We also filmed the feeding behavior of black-faced spoonbills to examine differences in feeding behavior by environmental factors. The survey showed that the number of black-faced spoonbills reached its peak from late April to late May which was the breeding period. Among a total of 308 black-faced spoonbills observed, 86.4% (n=266) were observed feeding on rice paddies, 90.6% (n=279) were adults, and none was observed on dry paddies. The biomass of rice paddy increased significantly since May when fish started hatching, and there was a significant difference in the amount of biomass between the rice paddies where black-faced spoonbills were observed and other rice paddies. The analysis of the feeding behavior of black-faced spoonbills showed that the feeding efficiency and feeding success rate of black-faced spoonbills increased significantly when the amount of biomass soared and that the number of steps of black-faced spoonbills per minute increased greatly after rice planting was completed. The number of bill sweeping was not related to the feeding efficiency, feeding success rate, and paddy type by cultivation stage.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.8
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• pp.1089-1098
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• 2018

In this paper, we propose an autonomous feeding robot and its obstacle classification system using ultrasonic sensors to secure the driving safety of the robot and efficient feeding operation. The developed feeding robot is verified by operation experiments in a cattle shed. In the proposed classification algorithm, not only the maximum amplitude of the ultrasonic echo signal but also two gradients of the signal and the variation of amplitude are considered as the feature parameters for object classification. The experimental results show the efficiency of the proposed classification method based on the Support Vector Machine, which is able to classify objects or obstacles such as a human, a cow, a fence and a wall.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.6
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• pp.50-56
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• 1994

This is an experimental study on the performance characteristics of Diesel Automobile with ultrasonic fuel feeding system. For this purpose, ultrasonic fuel feeding system was made and atomization characteristics was measured. Base on this result, carried out engine dynamometer test to investigate the performance characteristics of diesel automobile with ultrasonic fuel feeding system in comparison with conventional diesel fuel injector. The results are as follows. 1) In the spray characteristics test, fuel particle sizes were decreased about 11%~21%. 2) In engine dynamometer test, -The power was increased about 5%~11%. -The thermal efficiency was improved about 6%~11%. -The specific fuel consumption was improved about 6%~19%. -The smoke concentration was decreased about 11%~50%.

• Korean Journal of Environmental Agriculture
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• v.20 no.2
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• pp.122-126
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• 2001

The effect of the fermented food wastes (FFW) on growth performance and feeding efficiency war investigated in growing-finishing pigs. Four treatments with different mixing rates [0% FFW (100% commercial diet: control) ; 25% FFW ; 50% FFW ; and 100% FFW] were tried. Twenty heads of cross-bred barrows ($Duroc\;{\times}\;Landrace$, average live weight : 28.5 kg) were divided into 4 treatments with 5 replicates. During entire feeding trial (10 to 27 week), average daily gain increased by 29.4% and 13.9% in 25% FFW and 50% FFW, but decreased by 38.2% in 100% FFW compared to control. Daily feed intake was the highest in 25% FFW and it greatly decreased in 50% and 100% FFW feeding. The amount of feeds required for weight gain was similar with control in 25% FFW or significantly decreased in 50% FFW, while greatly increased in 100% FFW feeding. Cost of feeds per kg weight gain was decreased by 28.6%, 49.4% and 32.6% in 25%, 50% and 100% FFW, respectively. The results showed that replacement up to 50% with fermented food wastes was advantageous with respect to feed efficiency and feed cost, but 100% FFW feeding was disadvantageous because of a very low feed efficiency.

• Journal of Electrical Engineering and Technology
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• v.8 no.6
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• pp.1424-1430
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• 2013

This paper presents design procedure of the magnetic bearings used for high-speed electric machines and flywheel energy storage systems. Magnetic bearing can be categorized by inner-rotor type and outer-rotor type according to the position of the rotary disc. These two types are applicable based on application environments such as application space, required attraction force, and controllability. Magnetic bearing is generally designed based on the ratio (geometrical coefficient or geometrical efficiency) of pole width to rotor journal radius but proper ratio is only decided by the analysis. This is the difficulty of the magnetic bearing design. In this paper, proper design technology of the inner-rotor type and outer-rotor-type eight pole magnetic bearings is introduced and compared with the FEM analysis results, which verifies the proposed design procedure is suitable to be applied to the design of the magnetic bearings for the industrial applications and flywheel energy storage system.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.1
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• pp.58-63
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• 2011

This study investigated the effects of stocking density and feeding frequency (three and five times per week) on the growth of Pacific cod, Gadus macrocephalus. In the first experiment, experimental groups of fish (mean weight $167.8{\pm}41.4\;g$) were reared at three stocking densities (4, 8 and 12 kg/$m^3$) for 16 weeks. The total weight gain was 17.8, 17.1 and 35.4% at 4, 8 and 12 kg/$m^3$, respectively. The specific growth rates, survival rates and feeding efficiency increased with the density, but there were no significant differences (P>0.05). The daily feed intake decreased as the stocking density increased, whereas the condition factors increased with the stocking density (P<0.05). In the second experiment, groups of fish ($194.1{\pm}68.3\;g$) were fed either three or five times a week. The total wight gain was 14.4 and 18.5% for the fish fed three and five times per week, respectively. The specific growth rates of Pacific cod fed to satiation increased with the feeding frequency, although the difference was not significant (P>0.05). The survival rates, daily feed intake, feed efficiency, and condition factors of the Pacific cod were not significantly different (P>0.05). Based on these results, the optimum stocking density for juvenile cod is above 12 kg/$m^3$, and the best feeding frequency is three times a week, under the conditions used in this experiment.

• Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.299-304
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• 2009

The effects of different feeding regimes on the compensatory growth of olive flounder Paralichthys olivaceus were investigated. Seven treatments with triplicates of different feeding regimes were conducted, as follows: (1) fed twice a day 6 days a week for 8 weeks; (2) starved for 1 week, then fed twice a day 6 days a week for 3 weeks; (3) starved for 2 weeks, then fed twice a day 6 days a week for 6 weeks; (4) starved for 5 days, then fed twice a day for 9 days; (5) starved for 10 days, then fed twice a day for 18 days; (6) starved for 2 days, then fed twice a day for 5 days, starved for another 3 days, and fed twice a day 4 days; and (7) starved for 4 days, then fed twice a day for 10 days, starved for another 6 days, and fed twice a day for 8 days. Forty fish averaging 12.5 g, were hand-fed to satiation according to the designated feeding schedule. Fish from the control group gained more weight than those from any other group. Feeding efficiency did not vary among treatments. In summary, olive flounder subjected to fasting with different feeding regimes did not fully compensate growth compared to fish fed for 8 weeks without fasting. In addition, the less that fasted groups were subsequently fed, the lower their compensatory growth.

• Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.449-454
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• 2014

The effects of food deprivation and feeding ratio on the growth, feed utilization and body composition of juvenile olive flounder Paralichthys olivaceus were investigated in 810 juvenile fish averaging 6.4 g in weight randomly distributed in 27 400-L flow-through tanks. A 3 [food deprivation: 8-week feeding without food deprivation (8W), 7-week feeding after 1-week food deprivation (7W) and 6-week feeding after 2-week food deprivation (6W)]${\time}3$ (feeding ratio: 100%, 95% and 90% of satiation, hereafter denoted by 100, 95 and 90, respectively) factorial design was applied. The weight gain of the fish was significantly affected by both food deprivation and feeding ratio. The weight gain of the fish under the 8W-100 treatment was higher than that of those under the 7W-95, 7W-90, 6W-100, 6W-95 and 6W-90 treatments, but did not differ from those of fish under the 8W-95, 8W-90 and 7W-100 treatments. The specific growth rate (SGR) and the feed intake of the fish were affected by both food deprivation and feeding ratio. However, the feed conversion ratio (FCR) was unaffected by both food deprivation and feeding ratio. The protein efficiency ratio (PER) was affected by the feeding ratio, but not by food deprivation. The protein retention (PR) was affected by food deprivation, but not by feeding ratio. Juvenile olive flounder subjected to 1-week food deprivation at 100% satiation (7W-100 treatment) achieved full compensatory growth.

• Agribusiness and Information Management
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• v.4 no.2
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• pp.42-49
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• 2012

This study introduces cases of individual feeding systems for sow and the sow sorters which are the subparts of an eco-friendly feeding and management system based on a u-IT program using the hog feeding and management information system. The purpose of this study is to conduct an analysis of economic feasibility on cases of the improvement of the system using the u-IT and to provide information on the positive effects of an introduction of an eco-friendly pigsty and hog feeding and management system to hog raisers and government officials. The literature review and background section examine the effects of the introduction of u-IT technology into the field of livestock raising, hog feeding and management information system, and the eco-friendly feeding and management system based on the u-IT. This paper will present the results of the analysis on the effects and the economic feasibility of the individual feeding system for sow and the sow sorter utilizing the u-IT technology and information systems. The results of this study will contribute to the sustainable development of the hog raising industry by showing that the new feeding and management system utilizing the u-IT can not only increase the efficiency and productivity of farm management but also contribute to efficient, eco-friendly hog feeding and management.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.394-401
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• 2019

This study examined the effects of restricted feeding on the growth performance, carcass characteristics, and economic efficiency of finishing pigs for 27 days. A total of 24 finishing pigs (Landrace×Yorkshire×Duroc, average initial body weight of 81.52±1.11 kg) were allotted randomly to two treatments with 12 replicates (one pig per replicate). The experimental treatments were ad libitum feeding (AF), and restricted feeding (RF) with a 10% increase in offered feed than the day before if required. The results showed that the average daily feed intake (ADFI; p<0.001) of the pigs were improved in the RF treatment, but there were no changes in the average daily gain and weight gain to feed intake ratio (G:F). There were no significant differences in carcass weight and backfat thickness. In addition, the total pork price per pig was not affected by RF. Although total feed intake (TFI) and total feed intake cost (TFC) were significantly lower in the RF pigs (p<0.001), the feed cost per 1 kg weight gain (FCG) was similar regardless of the treatments. In conclusion, the RF method may decrease the feed cost due to a lower TFI and TFC.