• Asian-Australasian Journal of Animal Sciences
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• v.11 no.6
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• pp.774-780
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• 1998

This report includes an extensive bibliography of research articles investigating various facets of rearing neonatal piglets using liquid diets, and includes historical publications dating back to the 1940's. However, in order to provide concise and timely focus for application in modem swine production, only a selected number of recent findings are reviewed in detail. Collectively, the data presented illustrate that growth of piglets fed liquid diets can greatly exceed that of littermates fed dry diets and can even exceed growth rates of sow-reared controls (by up to 160%). The central questions that remain unanswered are: 1) Can this improved performance be obtained routinely and economically under applied farm conditions? and if so, 2) Does improved growth during the early-weaning period translate into improved net economic returns overall? Unfortunately, due to the current practical management constraints related to liquid-diet feeding (i.e., lack of an easy-to-manage feed delivery system), limited data are available which examine the efficacy of liquid-diet feeding under practical, commercial farm conditions.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.33-36
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• 2009

This study suggests manufacturing and cleaning the feeding system of hydrogen peroxide to use oxidizer of liquid rocket. We established the process of cleaning and passivation in order to minimize the pollution of Hydrogen Peroxide feeding system. And, we verified stability of the manufactured feeding system by leak test & hot test.

• Journal of ILASS-Korea
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• v.14 no.2
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• pp.65-70
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• 2009

An experimental study was performed to explore the atomization characteristics as the drop formation and the liquid breakup of an ethanol fuel using an electrohydrodynamic atomizer. A developed electrohydrodynamic atomizer controlled by a high AC power, a variable frequency, and a liquid feeding was used for the experiments. The test had been considered a disperse atomization processing at $450{\sim}4200V$ applied power, $200{\sim}400\;Hz$ frequency, and $1{\sim}3\;ml/min$ ethanol feeding to achieve an uniformed droplet formation. The goal of the research was to investigate the possibility of the liquid breakup for an ethanol fuel in an electrohydrodynamic atomizer. The results showed that the mean droplet radius decreased as the applied voltage increased or as the applied AC frequency increased. The whipping motion had been grown at the specified voltages due to the applied frequency.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.5
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• pp.563-566
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• 1996

Five crossbred heifers(Holstein Friesian $\times$ Hariana) aged about one year and average body weight 157.0 kg were used to observe the effect of UMLD with restricted amount of wheat straw (500 g/100 kg body weight) on body weight gain and nutrient utilization. After seven months feeding the animals were switched to a revival diet consisted of wheat straw and concentrate mixture, for an additional six months. Fortnightly body weights were recorded and metabolism trials were conducted at the end of the two experimental periods. Results indicated that the average daily gain were 57.0 and 413.3 g in two feeding systems. This showed a sub-optimum growth during UMLD feeding which was compensated when good quality revival diet was available. Though, the nutrients intake were significantly (p < 0.01) lower in UMLD feeding period as compared to revival diet feeding, but digestibility of all the nutrients were alike statistically. It can be concluded that UMLD with restricted amount of wheat straw can be fed as scarcity feed for a short period, without causing irreparable loss to the animals, provided sufficient feed nutrients are available after the scarcity period.

• Journal of Animal Environmental Science
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• v.7 no.1
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• pp.1-12
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• 2001

This study was conducted to develope an automatic liquid feeder for early weaning piglets and to test the efficacy of the system. The liquid feeder consists of water heating and discharge unit, dry diet storing and discharge unit, mixing and discharge unit, mixed liquid feed-delivering unit, and the central control part which control each unit, feeding frequency and the amount of feeding. For investigating the possibility of practical use, a feeding trial was carried out using eighteen three way crossbred piglets weaned on 19 days of age for the experimental period of six weeks. Experimental diet was provided in liquid form using the automatic liquid feeder for the first three weeks and in dry form for the later three weeks. The water heating and discharge unit exactly supplied warm water by 27 $m\ell$/s, into the mixing unit. The dry diet storing and discharge unit supplied dry feed by 3.7g/s, into the mixing unit. Being compared with the standard growth rate suggested by NRC, average daily gain of the piglets during the first three weeks of liquid feeding was lower by 10%, while it was higher during three weeks of dry feeding and over the whole experimental period by 24 and 17%, respectively. Feed/gain was 1.09, 2.14 and 1.89 for the first 3 weeks, later 3 weeks, and whole period, respectively. Diarrhea was observed for three days from day 3 to day 7 after feeding liquid diet, but no pig died of it. In conclusion, a preliminary test for the newly developed an automatic liquid feeder using 19 days of age weaning piglets showed that the unit was successfully operated without any major problems. Piglets raised on a liquid diet through the unit developed grew less during the first three weeks, but their growth and feed intake were greatly improved thereafter, indicating the developed automatic liquid feeder may be practically used in swine industry.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.241-244
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• 2006

The analysis of propellant feeding sub-system is performed using a commercial code SINDA/FLUINT, the comprehensive finite-difference, one-dimensional, lumped parameter tool. With the code, cryogenic helium supply system, liquid oxygen supply system, helium injection cooling system are evaluated. The code gave satisfactory estimation scheme for propulsion system characterized by cryogenic temperature and high pressure, two phase flow. This paper focuses on presenting calculation scheme of propulsion sub-system using one-dimensional code like SINDA/FLUINT.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.1
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• pp.35-44
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• 2011

Mathematical modelling for liquid rocket engine(LRE) main components were conducted to predict the dynamic characteristics when the LRE operates at the transient condition, which include engine start up, shut down, or thrust control. Propellant feeding system is composed of fuel and oxidizer feeding components except for regenerative cooling channel for the fuel circuit. Components modeling of pump, pipe, orifice, control valve, regenerative cooling channel and injector was serially made. Hydraulic tests of scale down component were made in order to validate modelling components. The mathematical models of engine components were integrated into LRE transient simulation program in concomitant with experimental validation.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.89-94
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• 2010

Fuselage propellant feeding system should supply propellants to engine with required flow rate, temperature and pressure. Propellant vibration in engine and feeding line changes feeding characteristics, and frequently inhibits to satisfy the required feeding requirements. Sloshing and POGO vibration are known to be the major vibration phenomena. Concerning sloshing and POGO, vehicle control and structural dynamics aspects are extensively studied, whereas, its effect on propellant feeding performance is not clearly understood. This paper focuses on the deviation of required feeding performance due to propellant vibration. Overall characteristics of propellant vibration and its effect on propellant supply to engine are reviewed and control mechanism for suppressing vibration is introduced.

• Journal of the Korean Society of Propulsion Engineers
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• v.6 no.4
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• pp.37-45
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• 2002

The development process of KSR-III propulsion feeding system is subscripted. The purpose of propulsion feeding system is to feed a certain amount of propellant from propellant tank to engine by the end of combustion. Pressure-fed liquid rocket, KSR-III has the unique characteristics of both pressure regulator and cavitation venturi as a passive flow control device. Main parameters of feeding system are confirmed by both water test and CFD(전산유체) technique. Flow control effect with venturi is confirmed by water test. Initial stabilization characteristic of pressure regulator is confirmed by real propellant test. And, to avoid the effect of resonance between rocket and feeding system, this article deal with POGO(포고) analysis to the feeding system.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.10a
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• pp.79-82
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• 2004

Propellant feeding system is the system to satisfy propellant feeding requirements(mass flow rate, pressure, temperature) at engine inlet of launch vehicle. Propellant feeding test facility is being constructed for the development scheme of pressurization system, processing in tank, propellant piping system, and flow control system that are main technologies in order to develope propellant feeding system. This paper introduces the propellant feeding test facility being constructed in KARI.