• The Korean Journal of Malacology
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• v.10 no.2
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• pp.41-46
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• 1994

The Antarctic soft-shelled clam, Laternula elliptica is widely distributed in shallow waters around the Antarctic Continent and islands. This bivalve species occurs in densepatches particularly in sheltered but frequently ice-impacted areas. This species mostly occurs at atound 20-30 m depth and is rarely found at depths shallower than 5 m where ice abrasion by drifting or grounded icebergs is severe. It burrows deep into sedimint(frequently >50 cm), which seems to be primarily a means for avoiding ice impacts. A pair of stout and highly extendable siphons appear to be a morphological reature to feed in the ice-scoured substrates while staying deep in the sedimint. As one of the largest bivalves in the Antarctic waters, L. elliptica appears to grow rapidly, reaching to a shell length of approximately 100 mm in 12 or 13 years. L. elliptica feeds sctively during summer when food is sufficiently provided, implying that food may be the most inportant fator regulating the growth. Seasonal variations in food availability, and metabolic process in starvation condition possibly during winter, however, are yet to be further investigated.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.8
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• pp.1298-1309
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• 1999

The nutritional value of protein varies between feedstuffs. It is possible to feed animals using crystalline amino acids as a sole nitrogen source, but in practice only some limiting amino acids are added to the diet. In order to use feedstuffs efficiently, it is important to determine exact amino acid requirements. Reported values differ widely because the requirements are affected by various factors. In this report, therefore, the factors affecting amino acid requirements are reviewed as follows: 1) availability of dietary amino acids, conversion factors of nitrogen to protein, interaction of amino acids, and strain, sex and age of animals; 2) amino acid requirements for maximum performance and maintenance, usefulness of non-essential amino acids; 3) plasma amino acid concentration as a parameter to determine amino acid requirements; and 4) nitrogen excretion to reduce environmental pollution. These factors should be considered, it is to improve the dietary efficiency, which is to reduce excess nitrogen excretion for environmental pollution.

• Journal of the Korean Ceramic Society
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• v.31 no.11
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• pp.1355-1361
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• 1994

With the availability of ceramics (Al2O3, Al2O3-TiC), it is possible to machine very hard steel at different cutting conditions. When hardened steel STD 11 is turned using ceramic tools, chip formation is observed conical-herical and arc chips with a cyclic saw toothed type. The main cause of saw toothed chip formation is observed conical-herical and arc chips with a cyclic saw toothed type. The main cause of saw toothed chip formation is found to be periodic gross shear fracture extending from the free surface of the chip toward the tool tip. In regard to chip control, ceramic Al2O3 is superior to the other cutting tools. The roughness of machined surface was getting worse with increasing of cutting speed and feed.

• Journal of information and communication convergence engineering
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• v.18 no.3
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• pp.147-154
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• 2020

In this study, we created a system that can determine the number of vehicles entering and departing a charging station in real time for solving waiting time problems during refueling. Accordingly, we use the You Only Look Once object detection algorithm to detect and count the number of vehicles in the charging station and send the data to the Firebase Realtime Database. The result is shown using an Android application that provides a map function with the Kakao Maps API at the user interface side. Our system has an accuracy of 91% and an average response time of 3.1 s. Therefore, this system can be used by drivers to determine the availability of a charging station and to identify the charging station with the least waiting time for charging their vehicle.

• Journal of the Korean Society for Precision Engineering
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• v.6 no.4
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• pp.71-83
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• 1989

The optimization in the machining process has been a long-standing goal of the manufacturing community. The optimization is composed of two main subjects;one is to select an optimum cutting condition, and the other is to detect the emergency situation and take necessary actions in real-time base. This paper proposes a reliable and practical guide system whose purpose is the optimization of cutting conditions, and the detection of tool failure in the machining process. The optimal cutting conditions are determined through the estimation of tool wear rate and the establishment of access- ible field from the measured cutting temperature and force. Tool breakage is detected by the normal force component acting on minor flank face extracted from on-line sensed feed force and radial force. In experiments, the proposed guide system has proved availability for the decision of reliable cutting conditions for the given tool-work system and the detection of tool breakage in ordinary cutting environments.

• Korean Journal of Poultry Science
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• v.15 no.4
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• pp.277-280
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• 1988

As a whole, the improvement of the weight gain ratio has rather a clear effect for the groups fed live yeast especially at 0.1% level, comparing with the control, and the nutrient digestibility is also improved, noticeably in protein digestibility. Feed intake is not, however, increased for the live yeast fed groups comparing with the control. The live yeast supplements are apparently responsible for the overall improvement in the nutrient availability and this, in turn, resulted in the weight gain of treated groups over the control.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.5
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• pp.157-163
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• 1997

In the case of direct connecting the nut of ballscrew to guide table, machining error and misalignment of ballscrew largely affect to the motional accuracy of guideway. For decreasing these influences, two type of floating couplings: leaf spring type and hybrid type which releases the table from nut of ballscrew except feed and rotational direction is proposed in this study. In order to verify practical availability of the proposed floating couplings, motional accuracy, dynamic characteristics and micro step response of hydrostatic guideway, mounted with each type of couplings are tested. The conventional fixed type coupling is also tested as the reference in characteristics. From the results of experiments, it is proved that the hybrid type coupling is superior to other couplings and is available to high precision feeding system with ballscrew.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.73-73
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• 2017

To set an optimal harvest time of main 7 whole crop silage rice cultivars, Nokyang(Ny), Mogwoo(Mw), Mogyang(My), Jungmo1029(Jm1029), Jungmo1038(Jm1038), Nokwoo(Nw) and Yeongwoo(Yw), based on feed value, we analyzed their feed values such as percent crude protein(CP), crude fat(CF), crude ash(CA), neutral detergent fiber(NDF), acid detergent fiber(ADF) and lignin. It was evaluated every 10 days from heading to 40 days after heading(DAH). Total digestible nutrient(TDN) and relative feed value(RFV) was also calculated from ADF and NDF. As results, CP was generally in decline as increasing DAH in Ny, My, Jm1029, Jm1038 and Yw and decreased to 20 DAH in Mw, decreased after increasing to 30 days in Nw. The CP content of Ny was relatively the highest ranged from 5.3% to 10.1% and Mw the lowest 4.5% to 5.2%, compared to others. CF content tend to decrease as DAH increase in Ny, My and Nw and decreased after increasing to 30 days Jm1029, increased after decreasing to 20 days Jm1038 but was not shown distinct trend of increase or decrease in Mw. Especially, that of Yw's CF gradually increased as harvest time late but relative content the lowest from 1.46% to 2.29% among 7 cultivars. The CA content of Ny, My, Jm1029 and Jm1038 approximately decreased as DAH increased and that of Mw was similar to others after heading, Nw decreased after 10 days and Yw increased after flowering. In all 7 cultivars, NDF and ADF had a tendency to decrease as days accumulated, in particular, Yw was the lowest on 30 DAH and so the content of Yw's TDN the highest(71.5%), while the lowest(67.2%) in Nw. For lignin, particularly, Mw tend to be in decline as DAH increase and was the lowest ranged from 1.34% to 1.87%. ADF analyses allows for the evaluation of in vivo digestible dry matter(DDM) and energy availability and NDF analyses provides the best indication of dry matter intake(DMI). Ultimately, the two factors can be combined to derive RFV for forage. RFV in general increased as DAH increased in all cultivars and was in order, Yw>My>Ny> Jm1038>Mw>Jm1029>Nw on 30 DAH. Taken together when these results, despite a slight increase of TDN after 30 DAH except Yw, considering forage yield potential, digestibility of grains and gradual decrease of CP and CF, the yellow ripe stage, about 30 DAH, was appropriate to harvest whole crop rice for silage use.

• Journal of Animal Science and Technology
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• v.45 no.5
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• pp.759-766
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• 2003

Two experiments were conducted to evaluate the nutritive values of defatted rice bran (DRB) and examine the effects of its dietary supplementation on broiler performances. In Experiment 1, to measure true metabolizable energy (TME), nitrogen corrected true metabolizable energy (TMEn), and true amino acid availability (TAAA), 30g of DRB sample was forced-fed to each of 16 ISA-Brown roosters followed by a 48h collection of excreta. The TME and TMEn values for DRB were 2.19 kcal/g and 2.05 kcal/g, respectively. The mean value of TAAA of the 15 amino acids in DRB was 77.29%. In Experiment 2, a total of 72 Avian broiler chicks were divided into 4 groups with 3 replicates of 6 birds per replicate, and fed one of the experimental diets containing 0, 5, 10 or 15% of DRB. Feed intake, weight gain, feed conversion rate, and body composition were measured for 3 weeks. Although there were no significant differences (P$\geq$0.05), body weight gain and feed intake of chickens fed a diet containing 15% DRB were slightly higher than those of the other groups. From these results, it can be concluded that feed formulation using TMEn and TAAA of DRB is an effective method for assuring feed quality and DRB can be supplemented to broiler rations up to 15% level.

• Korean Journal of Poultry Science
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• v.35 no.4
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• pp.381-389
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• 2009

This study was conducted to investigate the effect of corn distillers dried grains with solubles (CDDGS) in broiler diet on ileal amino acid digestibility and broiler performance. In experiment 1, TMEn of CGGDS ranged from 2,863 to 2,976 kcal/kg and averaged 2,904 kcal/kg on an 86% DM basis. In experiment 2, 192 male Ross broilers (one-day-old) were assigned randomly to 4 dietary treatment groups (12 birds/pen, 4 pens/treatment) as CDDGS levels (0, 6, 12 and 18%) and fed experimental diets for 6 weeks (starter ($0{\sim}2wk$); grower ($2{\sim}4wk$); finisher ($4{\sim}6wk$)). There was no difference in BWG of the chicks. However, feed intake and feed efficiency of chicks fed with non CDDGS groups were better than those of chicks fed with CDDGS fed groups (P<0.05). The amino acid digestibilities of diets containing CDDGS were high for phosphorus but low for lysine, threonine, aspartic acid, cystine and glycine (P<0.05) in the treatments compared to those of the control diet. This study showed that CDDGS has a high ME value and the treatments were low for the ileal amino acid digestibility, but there was no effect on the broiler performances.