• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.7
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• pp.508-516
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• 2003

The dynamic characteristics of an ell-lubricated, short squeeze film damper (SFD) with a central feeding groove are derived based on a theoretical analysis considering the effect of a groove, and identified experimentally using an Active Magnetic Bearing (AMB) system as an exciter. In order to get the theoretical solution, the fluid film forces of the grooved SFD are analytically derived so that the dynamic coefficients of the SFD can be expressed in terms of its design parameters. For the experimental validation of the analysis, a test rig using an AMB as an exciter is proposed. As an exciter. the AMB represents a mechatronic device to levitate and position the test Journal without any mechanical contact, to generate relative motions of the Journal inside the tested SFD and to measure the generated displacements during experiments with fairly high accuracy. Using this test rig, experiments are extensively conducted with various values of clearance, which Is one of the most important design parameters. in order to investigate its effect on the dynamic characteristics and the performance of the SFD. Damping and Inertia coefficients of the SFD that are experimentally Identified are compared with the analytical results to demonstrate the effectiveness of the applied analysis. It Is also shown that the AMB is an ideal device for tests of SFDs.

• Korean Journal of Ichthyology
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• v.29 no.3
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• pp.165-175
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• 2017

To minimize the damage caused by summer season such as high temperature and red tide, this study was conducted to investigate the effect of feeding and starvation on the survival rate, growth, growth restoration and physiological response of red seabream Pagrus major which were reared in marine net cage ($6m{\times}6m{\times}6m$). The feeding group was fed throughout the experiment for 10 weeks, whereas starvation group was not fed for 6 weeks and subsequent refeeding for 4 weeks. Survival rates of feeding and starvation groups were 94.4% and 98.1% respectively. The growth rate of starvation group was significantly lower than feeding group during starvation period, but recovered rapidly after feeding. The nutritional status such as albumin, total protein, total cholesterol, triglyceride also showed similar tendency to the growth data. Hematocrit and hemoglobin levels were higher in the feeding group than the starvation group during starvation period. Aspartate aminotransferase, glucose and total cholesterol were rapidly increased at the same time (in 5 week) in feeding group, whereas starvation group did not significant difference during starvation period. It was shown that the feeding group is more sensitive to stress than the starvation group. Thus, starvation can be applied as a rearing management plan of net cage fish farm in summer season.

• Journal of Animal Environmental Science
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• v.17 no.2
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• pp.107-114
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• 2011

This study was designed to determine the effect of season and split-sex feeding on performance, stress and carcass quality of finishing pigs. Two hundred and seventy cross-bred finishing pigs $(82.1{\pm}0.82kg)$ were randomly divided into six groups in 2 seasons (summer and winter) ${\times}$ 3 split-sex feeding (female only, castrated male and mixed) factorial arrangement of treatments. In winter, feed intake and weight gain of finishing pigs were better than summer (p<0.05). Split-sex feeding was affected the feed conversion, feed conversion of finishing pigs were superior in winter and mixed groups. Plasma concentrations of cortisol as a stress indicators was greater in the mixed groups vs female only and castrated male groups. There were no interactions between the season and split-sex feeding in their effects on these blood variables. The season was affected the carcass characteristics and PSE incidence of the finishing pigs, PSE incidence was low in winter and mixed groups. Meat quality did not show any significant difference due to the difference of season and split-sex feeding of finishing pigs. There was no significant difference in the pH, drip loss and meat color of pork loin between the season and split-sex feeding of finishing pigs. In conclusion, the results of this study suggest that we need more precise on-farm management practice in summer and application of split-sex feeding skills to reduce the stress and improve welfare status of finishing pigs.

• Proceedings of the Korean Nuclear Society Conference
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• 2001.05a
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• pp.387.1-387
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• 2001

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.2
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• pp.180-187
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• 2015

This study was conducted to determine the effects of feeding by-product feed (BF)-based silage on the performance, blood metabolite parameters, and carcass characteristics of Hanwoo steers. The BF-based silage was composed of 50% spent mushroom substrate, 21% recycled poultry bedding, 15% cut ryegrass straw, 10.8% rice bran, 2% molasses, 0.6% bentonite, and 0.6% microbial additive (on a wet basis), and ensiled for over 5 d. Fifteen steers were allocated to three diets during the growing and fattening periods (3.1 and 9.8 months, respectively): a control diet (concentrate mix and free access to rice straw), a 50% BF-based silage diet (control diet+50% of maximum BF-based silage intake), and a 100% BF-based silage diet (the same amount of concentrate mix and ad libitum BF-based silage). The BF-based silage was fed during the growing and fattening periods, and was replaced with larger particles of rice straw during the finishing period. After 19.6 months of the whole period all the steers were slaughtered. Compared with feeding rice straw, feeding BF-based silage tended (p = 0.10) to increase the average daily gain (27%) and feed efficiency (18%) of the growing steers, caused by increased voluntary feed intake. Feeding BF-based silage had little effect on serum constituents, electrolytes, enzymes, or the blood cell profiles of fattening steers, except for low serum Ca and high blood urea concentrations (p<0.05). Feeding BF-based silage did not affect cold carcass weight, yield traits such as back fat thickness, longissimus muscle area, yield index or yield grade, or quality traits such as meat color, fat color, texture, maturity, marbling score, or quality grade. However, it improved good quality grade (1+ and 1++) appearance rates (60% for the control group vs 100% for the BF-based silage-fed groups). In conclusion, cheap BF-based silage could be successfully used as a good quality roughage source for beef cattle.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.1
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• pp.43-50
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• 1995

This study was carried out to investigate the effects of activated carbon (AC) on growth, ruminal charateristics, blood profiles and feed digestibility in sheep, using roughage-based or concentrate-based diets. Twelve Suffolk breed of sheep of similar age and weight were distributed into 4 groups in a $2{\times}2$ factorial design. Two groups were fed a roughage-based diet with (R + AC) and without AC (R - AC), while the other two were fed a concentrate-based diet with (C + AC) and without AC (C - AC), respectively. The addition of 0.3% AC was based on dry matter of feed offered to animals. The incorporation of AC in roughage and concentrate based diets had no marked effects on feed intake, daily gain and feed conversion of the animals within experimental diets. The results obtained might be due to the low level of AC added in the diet. The animal on both concentrate-based diets were higher than the roughage-based diets in terms of daily gain and feed conversion ratio. However, it was observed that the animals provided with AC in the concentrate-based diet did not suffer from diarrhea and easily adjusted to high concentrate feeding. Further, the pH value for all diets before feeding was noted to be similar. After feeding, however, pH was shown to be higher in R + AC (p < 0.05) than in C + AC diet. Rumen protozoa number was decreased after feeding for both + AC diets, but in C - AC diet it was higher than in the roughage-based diets. For ammonia-nitrogen, C - AC was found to be higher than C + AC diet and the roughage-based diets before feeding. Total volatile fatty acid concentration, propionate and valerate molar ratios for both diets and time of collection were not affected. However, acetate, butyrate and valerate molar ratios were observed to be affected by diets and time of collections. The diets with AC increased (p < 0.05) before feeding for acetate molar ratio, but not different within diet, however, the roughage diets were found to be higher (p < 0.05) in acetate than the concentrate diet. In the blood parameters, the glutamic pyruvic transaminase (GPT), red and white blood cell (RBC, WBC) counts and packed cell volume (PCV) did not differ within and among the diets. Likewise, the WBC differential count in both diets with either - AC or + AC were similar in trend. However, lymphocyte count was noted to be increased in R + AC than the R - AC diet. The addition of AC in both diets did not affect nutrient digestibilities within diets.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.10
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• pp.1479-1484
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• 2005

A study was conducted to determine the effects of restricted feeding and feed form on the growth performance, characteristics of carcass and digestive tract, and days to first egg of Japanese quail (JQ, Coturnix coturnix japonica). A total of 240 oneweek-old JQ chicks were allocated randomly into 4 experimental groups that consisted of 3 replicates according to a 2${\times}$2 factorial arrangement for two feeding methods (ad libitum, AF and restricted feeding, RF) and two diet forms (mash, MD and crumble, CD). The JQ chicks were placed in a room with floor battery brooders and fed a commercial starter diet from 7 to 14 d of age. According to the experimental design, four treatments (1: ad libitum MD, 2: restricted MD, 3: ad libitum CD, and 4: restricted CD) were applied. Feed restriction was applied by 30% reduction of ad libitum feed intake for both MD and CD from 15 to 28 d of age. All birds were fed ad libitum with treatment diets from 29 d of age until the first laid egg seen (45 d of age). The commercial starter diet, MD and CD were in the same nutrient content (240 g crude protein with 13.4 MJ ME per kg diet). The body weight and overall feed conversion ratio (g feed/g gain) were higher (p<0.05) for the AF quails than the RF at 42 d of age. Carcass weights, dressing percentage and percentage yields of breast and back were similar for AF and RF groups at 42 d of age. The RF delayed (p<0.05) onset of egg production 2 days compared to the AF. Quail fed with the CD showed higher value (p<0.05) for carcass weight and dressing percentage at 42 d of age compared to birds fed with the MD. The interaction effect of feeding method${\times}$feed form on any of the studied parameters was not significant. The results suggest that feed restriction as in the present study can achieve a better feed conversion without reduction in carcass weight, and a significant benefit of feeding the crumble diet over the mash diet was obtained in terms of carcass weight in the JQ.

• Korean Journal of Community Nutrition
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• v.11 no.4
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• pp.449-458
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• 2006

The purpose of this study was to determine the characteristics of infants' temperaments and eating behaviors, mothers' eating behaviors and feeding practices in poor eating infants. The participants were 80 infants of 12-24 months (27 poor eaters and 53 matched normal controls) from a hospital and a public health center. Mothers were questioned about their eating behaviors and feeding practices, and infants' temperaments, eating behaviors, and nutrient intakes by one day food recall. Subjects were divided by mean nutrient adequacy ratio (MAR, < 0.75; poor eater). Intakes of Ca, P, Fe, Zn, thiamin, riboflavin, niacin, vitamin C, E, folate were below 75% RDA in poor eaters, whereas protein, thiamin, riboflavin, vitamin B$_6$, C, folate exceeded 125% RDA in good eaters. Rhythmicity of infants' temperaments and eating behaviors, restriction of mothers' eating behaviors and feeding practices were significantly lower, whereas activity levels of infants' temperaments were higher than good eaters. In multiple logistic regression model of poor eaters, activity of infants' temperaments (T, OR: 1.19, CI: 1.05 - 1.35) and attention spans of infants' eating behaviors (A, OR: 1.18, CI: 1.03 - 1.35) were significantly positive, whereas rhythmicity of infants' eating behaviors (R, OR: 0.79, CI: 0.61-0.94) was significantly negative [E (the legit) : -6.8644+0.1712$\times$T-0.2337$\times$R+0.1641$\times$A]. Our findings suggest that examination of eating behaviors, feeding practices, and temperaments will help target interventions to improve infants' food intakes, and these variables should be examined at the time of nutrition counseling.

• Journal of Animal Science and Technology
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• v.46 no.5
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• pp.811-820
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• 2004

Objectives of this study was to determine the comparisons of physico-chemical characteristics in crossbred pigs(Korean native breed ${\times}$ Landrace breed) by feeding periods. A total of 150 pigs were sampled from commercial farm, and assigned into three treatedrnents. Feeding peirods of Tl, T2 and T3 were below 200 days, 220-220 days, over 220 days, respectively. Live weight, carcass weight and backfat thickness were significantly(P<0.05) increased with feeding period increased, and final grade score have significantly(P<0.05) lower when feeding period was increased. pH and water content were significantly(P<0.05) lower when feeding period was increased(over 220days). However, intramuscular fat have no significantly different among the treatments. $L^* and b^* were significantly(P<0.05) lower and a^*$ was significantly higher(P<0.05) when feeding period increased. Cooking loss was higher in the order of Tl > T3 > T2. Shear force values was significantly(P<0.05) decreased by feed period increase. In fatty acids, myristic acid, palmitic acid, stearic acid and saturated fatty acid(SFA) in T2 were significantly(P<0.05) lower in T2, whereas linolenic acid, unsaturated fatty acid(UFA), essential fatty acid(EFA), UFA/SFA and EFA/SFA were significantly higher in T2 compared with other treatment. However palmitoleic acid and arachidonic acid were no significantly different with feeding periods. As a result of this study, crossbred pigs was increased live weight and carcass weight with feeding periods. and improved meat color and tenderness with feeding periods. However, final grade score was decreased with feeding periods

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.16 no.4
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• pp.261-268
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• 2013

Purpose: To investigate the clinical characteristics and outcomes among infants and toddlers with failure to thrive (FTT). Methods: This retrospective study was done with 123 patients who had visited Pusan National University Children's Hospital during their first two years of life and had received an FTT diagnosis. We compared the clinical characteristics of the patients based on the causes of their FTT and their ages at the time of first hospital visit. We investigated triggering factors, feeding practices, and outcomes in 25 patients with nonorganic FTT (NOFTT). Results: Eighty cases (65.0%) were NOFTT. The gestational ages, birth weights, and weights at the first visits were significantly lower in patients with organic FTT (OFTT) (p<0.05). Infants who had first visited the clinic at age <6 months had the least z-score. The percentage of patients with severe weight decline was higher in OFTT than in NOFTT (60.0% vs. 17.3%). The z-scores at the follow-up visits were improved after treatment in both of the groups. Preceding infection was the most common triggering factor of NOFTT and persecutory feeding as abnormal behavior of caregiver was observed in 22 cases (88.0%). After treatment with feeding method modification, all patients with NOFTT showed normal growth. Conclusion: Weight decline is more severe in OFTT patients and in younger patients at the first visit. Infants with FTT can attain normal weight gain growth by treating organic diseases and supplying proper nutrition in OFTT, and by correcting abnormal dietary behavior of caregiver in NOFTT.