• Journal of the Korea Institute of Building Construction
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• v.8 no.5
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• pp.119-125
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• 2008

In this paper, the estimation of super retarding concrete incorporating mineral admixtures at the same time including fly ash(FA), blast furnace slag(BS) are studied based on maturity method. The setting time was retarded, as super retarding agent contents increase and curing temperature decreases. In addition, apparent activation energy by Arrhenius function was ranged from $24\sim35$ KJ/mol with slightly difference along with mixture proportion. This value is smaller than existing value $30\sim50$ KJ/mol. Based on strength development estimation. it exhibited comparable relativity between prediction value and measurement value. Therefore, this study provided effective strength development prediction value with super retarding agent contents and mineral admixture combination. Strength development prediction equation provided herein is possibly valid for estimating accurate strength development of the super retarding concrete at the job site.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.12
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• pp.1880-1886
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• 2007

This study was conducted to examine the effects of different soy-oil and soy-lecithin levels on growth performance, nutrient utilization and serum parameters in broiler chickens. Two hundred and forty 1-day-old Arbor Acres chicks were randomly divided into 4 groups and treated as follows: basal diet with 2% soy-oil (SO); soy-oil and soy-lecithin mixture in proportion of 75/25 (SOL1), 50/50 (SOL2) and 2% lecithin (SL). At the end of the trial (42 d), birds in SOL1 group grew faster (p<0.05) and had better feed conversion efficiency (p<0.05) than other groups while SL group had the lowest performance (p<0.05). The utilization of ether extract was improved in SOL1 group (p<0.05) but apparent metabolizable energy (AME) and utilization of other nutrients decreased in SOL2 and SL group from 19 to 21 d. No significant effects were observed in apparent metabolizable energy, dry matter, crude protein and ether extract but the utilization of calcium and phosphorus was significantly improved in SL group (p<0.05) during 39 to 42 d. The birds fed with lecithin had lower serum total cholesterol and triglyceride than the control group (SO). Broilers fed with 2% lecithin (SL) had the highest insulin level (p<0.05). The results implied that soy-lecithin and soy-oil in a proportion of 25:75 had the highest growth performance and that soy-lecithin had cholesterol lowering capacity.

• Journal of the Korean Applied Science and Technology
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• v.19 no.1
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• pp.56-62
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• 2002

Microemulsion is stable to aggregation, sedimentation, fusion and has $3nm{\sim}200nm$ of particle size which is transparent and semitransparent. The isoflavone as a derivatives of Flavone is colorless crystalline compounds. It has similar basic structure to steroid materials which is hormone that acts to skin physiological phenomenon. On this study, we tried to search and demonstrate system content rate of dermal translocation system for cosmetics using O/W type microemulsion containing isoflavone. We manufactured O/W microemulsions by phase inversion emulsification method. It's was found that POE(20) monostearate with HLB value 14 caused microemulsion to be formed, which had $4nm{\sim}18nm$ of average diameter and $3nm{\sim}33nm$ of particle size distribution. Apparent viscosities of the microemulsions have increased in proportion to add surfactant dose.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.9
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• pp.1367-1375
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• 2008

This study was conducted to investigate the effects of phytase in diets containing cottonseed and soybean meal (CS) on growth performance, feed utilization and digestibility of protein and phosphorus in juvenile olive flounder (initial body weight 2.5 g), Paralichthys olivaceus. Four experimental diets replacing 0%, 30%, 30% and 40% fish meal protein with CS in equal proportion were formulated to be isonitrogenous and isocaloric (designated as CS0, CS30, CS30+P, CS40+P, respectively). Phytase of 1,000 FTU/kg was supplemented in diets CS30+P and CS40+P. Three groups of fish (25 fish per group) were fed one of the experimental diets for 10 weeks. No significant differences were observed in growth performance of fish groups except for the CS40+P diet. Apparent digestibility coefficients of protein and phosphorus in fish fed phytase-containing diets were significantly higher than those of fish fed the CS0 diet. Serum cholesterol was significantly reduced in fish fed the CS-containing diets. Antioxidant activities in the diets and liver of fish were significantly increased with the increment of dietary CS. Gossypol was only detected and found in liver of the fish fed the CS-containing diets. The findings suggest that supplementation of microbial phytase could improve the apparent digestibility of protein and phosphorus in juvenile olive flounder fed the CS-containing diets.

• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.81-87
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• 2014

Flow characteristics and the operating range of gas velocity was investigated for a two-stage bubbling fluidized-bed (0.1 m-i.d., 1.2 m-high) that had continuous solids feed and discharge. Solids were fed in to the upper fluidized-bed and overflowed into the bed section of the lower fluidized-bed through a standpipe (0.025 m-i.d.). The standpipe was simply a dense solids bed with no mechanical or non-mechanical valves. The solids overflowed the lower bed for discharge. The fluidizing gas was fed to the lower fluidized-bed and the exit gas was also used to fluidize the upper bed. Air was used as fluidizing gas and mixture of coarse (< $1000{\mu}m$ in diameter and $3090kg/m^3$ in apparent density) and fine (< $100{\mu}m$ in diameter and $4400kg/m^3$ in apparent density) particles were used as bed materials. The proportion of fine particles was employed as the experimental variable. The gas velocity of the lower fluidized-bed was defined as collapse velocity in the condition that the standpipe was emptied by upflow gas bypassing from the lower fluidized-bed. It could be used as the maximum operating velocity of the present process. The collapse velocity decreased after an initial increase as the proportion of fine particles increased. The maximum took place at the proportion of fine particles 30%. The trend of the collapse velocity was similar with that of standpipe pressure drop. The collapse velocity was expressed as a function of bulk density of particles and voidage of static bed. It increased with an increase of bulk density, however, decreased with an increase of voidage of static bed.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.6
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• pp.762-771
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• 2010

Two experiments were conducted to determine i) the fermentation characteristics of catfish by-product (C) ensiled with rice bran (RB) or sugarcane molasses (M) in different ratios, and ii) the digestibility of the silages in growing pigs. In the ensiling experiment, there were three ratios of C, ensiled with RB or M, of 8:2, 7:3 and 6:4 (wet basis for C and air-dry basis for RB and M). The six treatments were CRB8:2, CRB7:3, CRB6:4, CM8:2, CM7:3 and CM6:4, with 3 replications per treatment and seven sampling times. The pH of CRB7:3 and CRB6:4 decreased (p<0.05) from the first week and stayed stable until 8 weeks of ensiling, but the pH did not decrease in CRB8:2. The pH of CM8:2, CM7:3 and CM6:4 decreased rapidly from the first week until week 8. Dry matter (DM) and crude protein (CP) contents were slightly lower when catfish by-product was ensiled with RB than with M. Ammonia content in all treatments increased (p<0.05) during ensiling. Lactic acid content in silages with molasses increased from the first week, with the highest value at week 4. However, the lactic acid content in CRB8:2 did not increase with time and had the lowest value of all treatments. Acetic acid proportions of total volatile fatty acids were low at day 0, with the highest value at day 7, decreasing slowly until 8 weeks. The butyric acid proportion was highest at day 0 and decreased up to week 8. The proportion of propionic acid increased during ensiling. The digestibility experiment had a 4${\times}$4 Latin-square design and included 4 castrated crossbreed (Yorkshire${\times}$Landrace) male pigs fed four diets. The basal diet (BD) included rice bran, broken rice and maize meal, and the other three diets included fish meal (FMD) or catfish by-product ensiled with rice bran (CRBD) or sugarcane molasses (CMD). The silages chosen were those which gave the best results in the ensiling experiment for each additive. The coefficient of total tract apparent digestibility (CTTAD) of DM and organic matter (OM) was not significantly different among treatments. The CTTAD of CP was not different among the silage diets, but was lower in BD (p<0.01). The CTTAD of ether extract (EE) was higher in the catfish by-product silage diets than in FMD and BD. There was no significant difference in the digestibility of DM, OM, CP and EE between the fish meal and the by-product silages. In conclusion, catfish by-product can be successfully preserved by ensiling. Moreover, the total tract apparent digestibility of OM, CP and EE in ensiled catfish by-product was comparable with that of fish meal.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.6
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• pp.941-948
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• 2020

Objective: This study was carried out to determine the effects of elevated dietary cation and anion difference (DCAD) on dry matter intake (DMI) and ruminal fermentation pattern in lactating dairy goats under tropical conditions. Methods: Ten dairy goats were divided into two groups of five animals each. The groups received diets at different DCAD levels, either a control diet (22.81 mEq/100 g dry matter [DM], DCAD-23) or a DCAD-39 diet (39.08 mEq/100 g DM, DCAD-39). After parturition, DMI and water intake were recorded daily. Ruminal fluid and urine were collected, and nutrient digestibility measurements were carried out at 8th weeks postpartum (PP-8). Blood samples were collected at PP-4 and PP-8 to measure plasma leptin. Results: Dry matter intake/body weight (DMI/BW) at PP-8 of the animals fed the DCAD-39 diet was significantly higher than those fed with DCAD-23 diet (p<0.05). Animals fed with DCAD-39 consumed more water than those fed DCAD-23 over 24 h, particularly at night (p<0.05). Ruminal pH, acetate concentration, and urinary allantoin excretion increased with the DCAD-39 diet, whereas ruminal butyrate concentration was lower with the DCAD-39 diet. On the other hand, other ruminal parameters, such as total volatile fatty acid concentration, propionate molar proportion and acetate/propionate average ratio, were not affected by increased DCAD supplementation. Apparent digestibility was improved by increased DCAD supplementation. Plasma leptin concentration was higher with DCAD supplementation. Conclusion: When feeding goats with DCAD-39 under tropical conditions, an increase in DMI was associated with improved apparent digestibility of nutrients, ruminal fermentation and microbial protein synthesis. An increase in plasma leptin concentration could not explain the effect of high DCAD on DMI.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.1
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• pp.72-81
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• 2013

Four Luxi beef cattle ($400{\pm}10$ kg) fitted with ruminal, duodenal and ileal cannulas were used in a $4{\times}4$ Latin square to assess the effects of soybean small peptide (SSP) infusion on rumen fermentation, diet digestion and flow of nutrient in the gastrointestinal tract. The ruminal infusion of SSP was 0 (control), 100, 200 and 300 g/d. Ruminal SSP infusion linearly (p<0.01) and quadratically (p<0.01) increased microbial protein synthesis and rumen ammonia-N concentration. Concentrations of total volatile fatty acid were linearly increased (p = 0.029) by infusion SSP. Rumen samples were obtained for analysis of microbial ecology by real-time PCR. Populations of rumen Butyrivibrio fibrisolvens, Streptococcus bovis, Ciliate protozoa, Ruminococcus flavefaciens, and Prevotella ruminicola were expressed as a proportion of total Rumen bacterial 16S ribosomal deoxyribonucleic acid (rDNA). Butyrivibrio fibrisolvens populations which related to total bacterial 16S rDNA were increased (p<0.05), while Streptococcus bovis populations were linearly (p = 0.049) and quadratically (p = 0.020) decreased by infusion of SSP. Apparent rumen digestibility of DM and NDF were (Q, p<0.05; L, p<0.05) increased with infusion SSP. Total tract digestion of DM, OM and NDF were linearly (p<0.01) and quadratically (p<0.01) increased by infusing SSP. The flow of total amino acids (AA), essential amino acids (EAA) and individual amino acids were linearly (p<0.01) and quadratically (p<0.01) increased with infusion SSP. The digestibility of Lysine was quadratically (p = 0.033) increased and apparent degradability of Arginine was linearly (p = 0.032) and quadratically (p = 0.042) increased with infusion SSP. The results indicated that infusion SSP could improve nutrient digestion, ruminal fermentation and AA availability.

• Journal of Korea Water Resources Association
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• v.43 no.6
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• pp.517-524
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• 2010

In this study, the 1D apparent shear stress model for vegetated compound open-channel flows was suggested. To consider the effect of momentum exchange between main channel and floodplain, the eddy viscosity concept was used in the present model. The interfacial eddy viscosity in the interface of main channel and floodplain was determined from the 3D Reynolds stress model. The evaluated interfacial eddy viscosity appears to be good agreement with those proposed previously. To investigate the effect of interfacial eddy viscosity, sensitive analysis was carried out. the computed backwater profiles are nearly identical with respect to the value of the interfacial eddy viscosity. However, the discharge conveyed by the floodplain changes is proportional to the interfacial eddy viscosity. Finally, the changes of the interfacial eddy viscosity due to the vegetation density and vegetation height were examined. The computed results of interfacial eddy viscosity are in proportion to the vegetation density and vegetation height, and the interfacial eddy viscosity has a range of $(2-5)\;{\times}\;10^{-4}$.

• Korean Journal of Ichthyology
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• v.27 no.2
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• pp.142-148
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• 2015

The feeding habits of the Pacific cod Gadus macrocephalus were studied using 620 specimens collected by bottom trawl and pound net in the Southeast sea of Korea, from February 2012 to June 2013. Of 620 specimens, 192 contained food and 428 were empty. The total length (TL) of individuals used in this study ranged from 20.4 to 95.2 cm. Pacific cod mainly consumed Pisces, Macrura, and Cephalopoda. Its diet also included small quantities of Anomura, Brachyura, Mysidacea, Isopoda and Amphipoda. The proportion of Pisces in prey items increased with increasing Pacific cod length, but seasonal difference was not observed. The proportion of Macrura and Cephalopoda decreased with growth, and seasonal differences were apparent. Macrura were taken there mainly from autumn to winter, whereas Cephalopoda were consumed from spring to summer.