• Journal of Electrical Engineering and Technology
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• 제8권6호
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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.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.610-614
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• 1996

As the run out error and misalignment of ball screw connected directly to guide table largely affect the motion accuracy of guideway, floating coupling that releases the table from screw nut except feed and rotational direction is needed todecrease its influences. The purpose of this study is to propose a practical model floating coupling of ball serew for high precision feeding system. The straightness, dynanic characteristics and micro step response of hydrostatic guideway, mounted with three types of coupling fixed type, leaf spring type and hydrostatic type, are tested and compared. From the resuts of experiments, it is proved that a hydrostatic type floating coupling is superior to other couplings and is available to high precision feeding system with ball screw.

• Asian-Australasian Journal of Animal Sciences
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• 제1권4호
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• pp.223-232
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• 1988

Fifty-two wether lambs weighing 30 kg were randomly assigned to 5 treatment groups; 1) initial slaughter. 2) control-maintenance (CON-MT), 3) control-ad libitum (CON-AL), 4) cimaterol-maintenance (CIM-MT) and 5) cimaterol-ad libitum (CIM-AL). Ad libitum-fed animals had free access of a high-concentrate diet, whereas maintenance animals were restricted in feed intake to maintain the initial weight of 30 kg for 90 days. Cimaterol was administered in the feed at 10 mg/kg. Regardless of feeding level, the administration of CIM improved carcass weight (p < .05), dressing % (p < .01), longissimus muscle area (p < .01), leg conformation and muscling (p < .01), USDA yield and quality grades (p < .01) and protein concentration (p < .01) in carcass as well as in muscle. Cimaterol feeding decreased organ wt (p < .01), baekfat depth (p < .01), intramuscular fat and overall fatness. Cimaterol was effective for muscle accretion even under restricted feeding condition. The greater accretion of muscle was the result of the hypertrophy of both type I and type II muscle fibers but the hypertrophy of type II fiber (110%) was much greater than that of type I fiber (37%). Cimaterol feeding decreased muscle DNA concentrations but the number of nuclei per muscle fiber was not changed, indicating that the lower DNA concentration was due to the dilution effect caused by the hypertrophy of muscle fiber. As evidenced by lower flank streaking, lower marbling and darker muscle, CIM feeding adversely affected meat quality. Meat tenderness was also adversely affected, resulting in significantly (p H .01) tougher meat in CIM-fed animals.

• Asian-Australasian Journal of Animal Sciences
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• 제20권8호
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• pp.1182-1189
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• 2007

An intracerebroventricular (ICV) infusion of somatostatin 1-28 (SRIF) was used as a thirst-controlling peptide antagonist to investigate whether or not thirst-controlling peptides are involved in the significant decrease in feed intake during the initial stages of feeding large-type goats on dry forage. A continuous ICV infusion of SRIF was conducted at a small dose of $4{\mu}g$ ml/h for 27 h from day 1 to day 2. Goats (n = 5) were fed roughly crushed alfalfa hay cubes for 2 h twice daily and water was given ad libitum. Feed intake was measured during ICV infusion of artificial cerebrospinal fluid (ACSF) and SRIF. The feed intake during SRIF infusion increased significantly compared to that during ACSF infusion. In comparison to the ACSF treatment, plasma osmolality during the SRIF treatment significantly decreased during the first half of the 2 h feeding period. The factor causing the decrease in plasma osmolality during the ICV infusion of SRIF was a decrease in plasma Na, K, Cl, and Mg concentrations. In comparison to the ACSF infusion treatment, parotid saliva secretion volumes during the 2 h feeding period in the SRIF infusion treatment were significantly larger. While there was no significant difference in cumulative water intake (thirst levels) between the SRIF and the ACSF treatments upon conclusion of the 2 h feeding period, based on the plasma osmolality results it is thought that thirst level increases brought about by alfalfa hay cube feeding in the first half of the feeding period were reduced. It is thought that the somatostatin-induced increases in feed intake during the 2 h feeding period in the present experiment were caused by decreases in plasma osmolality brought about by the somatostatin infusion. As a result, it is suggested that the significant decrease in feed intake during the initial stages of feeding in large-type goats given roughly crushed alfalfa hay cubes, was due to the actions of thirst-controlling peptides.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2005년도 제31회 KOSCO SYMPOSIUM 논문집
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• pp.162-169
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• 2005

The performance of oxygen combustion with $CO_2$ feeding was investigated in a pyrex tube furnace. The inverse type multi-hole burner was used for improving mixing and wide operating range. It introduced oxygen, fuel, and oxygen, respectively, from center tube to outer tubes. Oxygen combustion characteristics with excess oxygen ratio, oxygen feeding ratio, and $CO_2$ feeding flow rate were studied to optimize the operating condition and to apply the oxygen combustion with recirculation of flue gas to a real furnace. This paper presents results on the effect of $CO_2$ feeding flow rate on the structure of the flames and concentrations of NO and CO emissions. The visible flame length was shortest due to well mixing between fuel and oxygen when the oxygen feeding ratio was 0.25. The NO emission was reduced drastically regardless of excess oxygen ratio when the $CO_2$ feeding flow rate was larger than 15 lpm. The CO emission is varied by changing the $CO_2$ feeding flow rate but the CO emission characteristics is highly affected by excess oxygen ratio. When the excess oxygen ratio is below ${\lamda}=1.1$, the CO emission increased as the $CO_2$ feeding flow rate increased.

• Asian-Australasian Journal of Animal Sciences
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• 제25권3호
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• pp.341-352
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• 2012

In large-type goats that were fed on dry forage twice daily, dry forage intake was markedly suppressed after 40 min of feeding had elapsed. The objective of this study was to determine whether or not marked decreases in dry forage intake after 40 min of feeding are mainly caused by the two factors, that is, ruminal distension and increased plasma osmolality induced thirst produced by dry forage feeding. Six large-type male esophageal- and ruminal-fistulated goats (crossbred Japanese Saanen/Nubian, aged 2 to 6 years, weighing $85.1{\pm}4.89kg$) were used in two experiments. The animals were fed ad libitum a diet of roughly crushed alfalfa hay cubes for 2 h from 10:00 to 12:00 am during two experiments. Water was withheld during feeding in both experiments but was available for a period of 30 min after completion of the 2 h feeding period. In experiment 1, saliva lost via the esophageal fistula was replenished by an intraruminal infusion of artificial parotid saliva (RIAPS) in sham feeding conditions (SFC) control, and the treatment was maintained under normal feeding conditions (NFC). In experiment 2, a RIAPS and non-insertion of a balloon (RIAPS-NB) control was conducted in the same manner as the SFC control of experiment 1. The intraruminal infusion of hypertonic solution and insertion of a balloon (RIHS-IB) treatment was carried out simultaneously to reproduce the effects of changing salt content and ruminal distension due to feed entering the rumen. The results of experiment 1 showed that due to the effects of multiple dry forage suppressing factors when feed boluses entered the rumen, eating rates in the NFC treatment decreased (p<0.05) after 40 min of feeding and cumulative dry forage intake for the 2 h feeding period reduced to 43.8% of the SFC control (p<0.01). The results of experiment 2 indicated that due to the two suppressing factors of ruminal distension and increased plasma osmolality induced thirst, eating rates in the RIHS-IB treatment were, as observed under NFC, reduced (p<0.05) and cumulative dry forage intake for the 2 h feeding period decreased to 34.0% of the RIAPS-NB control (p<0.01). The combined effects of ruminal distension and increased plasma osmolality accounted for 77.5% of the suppression of dry forage intake 40 min after the start of dry forage feeding. The results indicate that ruminal distension and increased plasma osmolality induced thirst are the main factors in the suppression of dry forage intake in large-type goats.

• 한국축산시설환경학회지
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• 제7권1호
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• pp.13-20
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• 2001

This study was conducted to investigate the actual conditions on housing and facilities for goat. This investigation of the actual conditions was investigated by the style of farm which was divided into sideline scale and speciality scale included 47 farms. The results are summarized as follows: Rearing scale was 48.9% for 50-100 heads per farm. Rearing type was 46.8% for grazing type and 53.2% for barn type. Housing type was 27.7% for simple frame housing and 72.3% for permanent housing. Pipe was used 80.8% with Pillar and Girder as the housing frame at farm. For the pipe used in farm, 27.7% of them was used for simple frame housing. Side wall was composed of cement and winch curtain to be 29.8%, slate roof to be 40.4%, pipe partition to be 38.3%, and cement floor to be 51.1%. Materials of feeding trough were wood and Zinc grater to be 41.5%, respectively. Type of feeding trough was square to be 70.2%. The feeding trough was located in barn to be 48.9%. Material of water supply facilities was plastic to be 87.2%. Type of water supply facilities was mostly square to be 76.6%. Water-trough was located in playground to be 48.9%. Parturition facilities were consisted of partition structure by group to be 42.5% and were mainly composed of pipe and wood. 46.8% of the barn did not have delivery room in the farm.

• 대한간호학회지
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• 제42권2호
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• pp.181-189
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• 2012

Purpose: This study was done to compare breast feeding rates and factors influencing feeding practice between late preterm ($34{\leq}GA<37$) and preterm infants (GA<34). Methods: A survey was done of 207 late preterm and 117 preterm infants in neonatal intensive care units (NICU) of 4 university hospitals in D city. Data were collected from July 2009 to June 2010 from 324 medical records in the NICU. Breast-feeding at home was checked either by telephone survey or questioning during hospital visits. Results: Rate of breast feeding for late preterm infants was significantly lower than for preterm infants. There was no significant difference in breast-feeding at home. We found differences in factors influencing breast feeding between the two groups. Factors influencing feeding for late preterm infants were type of delivery, mothers' occupation, feeding type during hospitalization, time elapse from hospital discharge, total admission days, infant's body weight at first feeding and length of NPO (nothing by mouth). Factors influencing feeding for preterm infants were birth order, maternal disease and obstetric complications, and one-minute Apgar score. Conclusion: Results of the study show low rates of breast-feeding for late preterm infants indicating a need for breast-feeding education for mothers of these infants.

• 한국정밀공학회지
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• 제14권5호
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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.

• Asian-Australasian Journal of Animal Sciences
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• 제33권12호
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• pp.2031-2038
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• 2020

Objective: This study aimed to determine the effect of intermittent feeding and cold water on performance and carcass traits in broiler chickens between 4 to 6 wk of age exposed to daily high temperature. Methods: Broilers were assigned to four treatment groups according to a 2×2 factorial design between 22 to 42 d of age (80 broilers per treatment, 4 replications). Broilers were divided into two main groups as feeding type (ad-libitum [AL] and intermittent [IF] for 6 h daily) and sub-groups as water temperature (normal [NW], 24.9℃ and cold [CW], 16.4℃). Heat treatment was applied between 11.00 to 17.00 h daily between 22 to 42 d of age. Results: Live weight at 6th wk was not affected by feeding type and water temperature, but the live weight was significantly higher in IF chickens at the 5th wk (p<0.05). Average weekly gain of IF broiler chickens were higher compared to AL group at 4, 5, and 6 wk of age (p< 0.05). Although feeding type did not affect feed intake in 4 and 5th wk, feed intake was higher in IF chickens at 6th wk (p<0.01). In addition, feeding type and water temperature did not affect feed conversion ratio and interactions were not significant (p>0.05). Water temperature had no significant effect on heart, liver, gizzard, and abdominal fat percentages (p>0.05). Conclusion: It is concluded that IF increased the average weekly gain in chickens reared under daily heat stress for 6 h between 22 to 42 d of age. IF in hot environmental conditions slightly increased performance without adversely affecting health, welfare, and physiological traits, whereas CW implementation had no significant effect on performance. It can also be said that IF suppresses a sudden increase in body temperature depending on age and live weight.