• Journal of Advanced Marine Engineering and Technology
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• v.32 no.8
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• pp.1303-1308
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• 2008

Keeping cooling water temperature higher within the allowable range helps marine engines to run in more efficient condition especially when the engine load is low. Temperature control of jacket cooling water in outlet side of main engine has been more widely adopted to ships these days for the purpose to reduce fuel consumption rate. But If the temperature sensor for the control loop is placed at the outlet of engine, it brings more difficulties in attaining stable and desirable properties due to dead times included in pipe length and engine itself comparing to the case where the measuring point is at the inlet side of main engine. In relation with this problem, Feed-forward control could be one of realistic solutions as it reveals good properties and requires less cost for system configuration. This study suggests a forward control system which leads to improved temperature control performances to disturbance signals which could arise from variation of engine load or weather condition. Two dead times in the modelling were described, considering pipe length between the actuator and the engine as well as the thermal process inside the engine. The results of analysis were shown by simulations to confirm responses under different conditions.

• Applied Chemistry for Engineering
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• v.5 no.5
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• pp.772-778
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• 1994

The pervaporation separation experiments of phenol-water mixtures were carried out by using Type 1 (PDMS : crosslinking agent= 1 : 0.25) and Type 2 (PDMS : crosslinking agent= 1 : 0.35) silicone rubber membranes at 30, 40 and $50^{\circ}C$. The phenol concentrations in the feed to be separated were 500 ppm to 5 wt%. Type 2 membranes were more efficient than Type 1 membranes for the separation of phenol-water mixtures. The phenol concentration of 70wt% was obtained for 5wt% of phenol concentration in the feed at $30^{\circ}C$ and 11wt% phenol concentration observed for 500ppm of phenol concentration in the feed at $30^{\circ}C$ by using Type 2 membranes.

• Fisheries and Aquatic Sciences
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• v.6 no.4
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• pp.194-202
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• 2003

Budgets for water, nitrogen, and chemical oxygen demand (COD) were determined in two 0.012 ha earthy-bottom ponds stocked with Israeli strain common carp at an initial stocking density of $20\;fish/m^3$. Total ammonia nitrogen (TAN) concentrations increased continuously but later decreased in pond A as a consequence of high nitrification. COD concentrations increased during the experimental period due to the accumulation of feed input. Nutrient budgets showed that feed represented $94-95\%$ of nitrogen input and about 99% of organic matter input. Fish harvest accounted for $40\%$ of nitrogen and organic matter input. Seepage and water exchange removed $15-17\%$ of nitrogen input but only $1-2\%$ of organic matter. Draining of the ponds removed $20-26\%$ of input nitrogen, mostly in inorganic forms, but removed only minus organic matter. Fish and water column respiration accounted for $39\%$ of organic matter input, and benthic respiration accounted for $7-12\%$ of organic matter input. No significant change of nitrogen and organic matter in both pond bottoms were found during the three-month growth period. The unrecovered input nitrogen, about $6.3-13\%$, was lost through denitrification and ammonia volatilization. On a dry matter basis, fish growth removed $31\%$ of total feed input and left $69\%$ as metabolic wastes.

• Textile Coloration and Finishing
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• v.21 no.6
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• pp.56-63
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• 2009

In this study we have evaluated the separation characteristics and concentration of sericin using tubular type ultrafiltration membrane in silk degumming solution that extracted from electrolytic reduction water process. Ultrafiltration membranes have used in sericin separation performance and the separation characteristics of membrane satisfied typical Hagen-Poiseuille equation. It had the increase of flux according to the increase of feed pressure and temperature in occasion of pure water flux. And also the flux and solute rejection had about $25{\sim}60{\ell}/m^2{\cdot}h$ and more than 95% in sericin feed solution with concentration 1.00~1.89% at feed pressure force of $3{\sim}8kgf/cm^2$ respectively. In addition, the separation performance of tubular type ultrafiltration membrane for silk degumming solution was very steady-state with long experiment time.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.2
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• pp.85-92
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• 2015

Since the consumption of the livestock products increased for the past 10 years in Korea, the water use for live animals has become more important in terms of water savings. Therefore, the index connecting water use and livestock products consumption should be required for sustainable water management, and water footprint concept could be suggested as the index. The aim of this study is to estimate the water footprint for livestock products; beef cattle, swine, and broiler chicken. The water footprint for livestock products is divided into direct and indirect water. The direct water includes the drinking and servicing water, and the indirect water includes the water for the cultivation of feed crops. The water footprint of beef cattle was calculated to $17,023.1m^3/ton$, and direct water was $91.2m^3/ton$, and indirect water was $16,931.9m^3/ton$. The water footprint of swine was calculated to $4,235.8m^3/ton$, and direct water was $129.7m^3/ton$, and indirect water was $4,106.0m^3/ton$. The water footprint of broiler chicken was calculated to $2,427.7m^3/ton$, and direct water was $7.6m^3/ton$, and indirect water was $2,420.1m^3/ton$. Also, we compared the water footprint to water demand of water vision 2020 which is the main report for national water management. The water vision 2020 reported only direct water for live animal, but the water footprint includes the direct and indirect water. Therefore, the water footprint could be applied to various fields relating water and food.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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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.

• Membrane Journal
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• v.9 no.3
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• pp.163-169
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• 1999

The effects of interactions between permeant molecules or permeant and membrane material have been investigated on the permeation behavior of permeants in pervaporation of water/alcohol mix¬tures. A poly(vinyl alcohol) (PVA) membrane crosslinked with glutaraldehyde was employed in this study. A homologous series of alcohols in aqueous solution were used as feed. The pervaporation experiments were carried out with feed having 70-97 wt.% of alcohol contents and at various feed temperatures. In a high alcohol content above 92 wt.%, the permeation rate was increased in the order of interaction strength between alcohol and water in feed. However, in a low alcohol content below 90 wt.%, the tendency of the permeation rate was found to be opposite. These observations were discussed in terms of changes in interaction between permeant/permeant or permeant/membrane in varying feed composition and feed temperature.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.3
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• pp.401-409
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• 2012

The study was conducted to investigate the chemical composition of distillery yeast sludge and its inclusion in broiler diets to replace canola meal. Raw distillery yeast sludge was washed with water using water and sludge in the ratio 6:1, respectively. Proximate analysis of raw distillery yeast sludge and washed distillery sludge was carried out for crude protein (CP), true protein (TP), ether extract (EE), ash, acid insoluble ash and nitrogen free extract (NFE) determination. Mineral contents and amino acid profile of raw distillery yeast sludge and washed distillery sludge were also determined. After chemical evaluation, four iso-caloric and iso-nitrogenous broiler starter and finisher diets were prepared in mash form using 0 (control), 4, 8 and 12% levels of washed distillery sludge replacing canola meal. One hundred and twenty day-old broiler chicks were randomly distributed into 12 experimental units in such a way that each diet was offered to three experimental units, each comprising of 10 chicks. It was observed that washing affected the nutrients either by decreasing or increasing their concentration. It decreased the total mineral contents whereas CP, TP, EE and NFE contents increased. Washing also increased amino acid profile. Average feed intake and weight gain were higher in birds fed diet containing 8% washed distillery sludge and lower in birds fed diet containing 0% washed distillery sludge. Feed cost per kg live weight gain decreased significantly as the level of washed distillery sludge was increased in the diet. Average heart, liver and pancreas weights decreased with increased level of washed distillery sludge in the diet. The study revealed that after washing, distillery yeast sludge can be used successfully in broiler diets up to the level of 8% without any adverse effect on broiler's performance.

• Nutrition Research and Practice
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• v.3 no.1
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• pp.38-42
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• 2009

We conducted two studies to determine the effect of gender, gonadectomy (GDX) on growth and plasma cholesterol levels in pigs. In experiment 1, five sham-operated and five GDX female Landrace pigs (26kg) were allowed to have free access to water and feed up to market weight (approximately 100kg). Body weight and feed consumption were recorded biweekly, and daily body weight gain, daily feed intake and feed efficiency (gain/feed) were calculated during the feeding period. In experiment 2, 10 male (26kg) and 10 female (26kg) Landrace pigs were used; five male and five female pigs were assigned to sham-operated or GDX. Pigs were allowed to have free access to water and a diet without added cholesterol (Table 1) until they were 6 months old (male 104 and female 98kg) and thereafter they were fed a hypercholesterolemic diet (Table 1) containing 0.5% cholesterol and 0.1% cholate for 10 days. GDX of female pigs increased average daily gain (P<0.05), compared with their sham-operated counterparts during the growing-finishing period, but had no effect (P>0.05) on feed efficiency. Plasma cholesterol levels in pigs fed a hypercholesterolemic diet for 10 days were much higher (P<0.05) in females than in males (161 vs 104mg/100mL plasma), and were increased by GDX only in male pigs. HDL-cholesterol/LDL+VLDL-cholesterol ratio appeared to be higher in males than in females, and was not influenced by GDX in either sex. Results suggested that the lower growth rate of female pigs than their male counterparts is attributable to the ovarian activity, and the lower plasma cholesterol level in male than in female pigs fed a hypercholesterolemic diet is due to the testicular activity.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.9
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• pp.1267-1271
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• 2001

The objective of this study was to examine the significance of feeding induced hypovolemia (decrease in plasma volume) in controlling the feed intake of goats fed on dry feed. In order to alleviate hypovolemia with feeding, a 2 h intravenous infusion (16-18 ml/min) of artificial saliva or mannitol solution was begun 1 h prior to feeding and continued until 1h after the start of the 2 h feeding period. In comparison with no infusion (NI), cumulative feed intake was increased by 41% with artificial saliva infusion (ASI) and by 45% with mannitol infusion (MI) by the completion of the 2 h feeding period. Both infusion treatments (ASI and MI) were significantly different (p<0.05) from the NI treatment in terms of the cumulative feed intake. The cumulative feed intake between the ASI and MI treatments was not significantly different (p>0.05). No infusion treatment (NI) had the lowest cumulative feed intake (929 g DM), whereas MI had the highest (1345 g DM), after completion of the 2 h feeding period. Generally, infusion treatments also increased the rate of eating at all time points after feeding was commenced. Following the first 30 mins of feeding, the rate of eating decreased sharply, and subsequently declined gradually in all treatments. Compared to the NI, both ASI and MI significantly (p<0.05) decreased thirst level (water intake for 30 mins after the completion of the 2 h feeding period) by approximately 13%. However, the thirst level caused by ASI and MI was not significantly different (p>0.05). Both ASI and MI decreased the plasma concentrations of osmolality and total protein, and hematocrit at 1 h after infusion. The results suggested that the thirst sensation in the brain could be produced by feeding induced hypovolemia. Moreover, the results indicate that hypovolemia is one of the factors controlling the feed intake of goats fed on dry feed.