• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.785-792
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• 2013

Two studies were conducted to investigate the effects of dietary nucleotides (NT) on the growth performance, hematological parameters, and innate immune responses of red seabream Pagrus major. In Expt I, six experimental diets were formulated: a control, four that contained each NT at a level of 0.15% (inosine monophosphate, IMP; adenosine monophosphate, AMP; guanosine monophosphate, GMP; and uridine monophosphate, UMP), and one with a 1:1:1:1 mixture of NTs (IMP, AMP, GMP, and UMP). In Expt II, five experimental diets were formulated that contained 0, 0.1, 0.2, 0.4, and 1.0% IMP (commercial product). Triplicate groups of juvenile (initial body weight 33.1 g) and growing (initial body weight 120 g) red seabream were fed one of the experimental diets to apparent satiation for 8 weeks in Expt I and 12 weeks in Expt II. In Expt I, fish fed diets with NT had higher growth performance than the control group. The nitroblue tetrazolium and lysozyme activities were higher in fish fed the mixed-NT diet, and lowest in the control group. In Expt II, the final body weight and feed utilization of fish fed the 0.1% IMP diet were significantly higher than those of fish fed the control or 1.0% IMP diets. Diet palatability was improved significantly when 0.1% IMP was added. The lysozyme activity was higher in fish fed diets with 0.4-1.0% than in the control group. These results suggest that supplementation of 0.15% IMP and Mixed-NTs in diet can enhance the growth and immune responses in juvenile red seabream. The optimum IMP level appears to be 0.2% in practical feed formulation for growing red seabream.

• Journal of the Korean Society for Railway
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• v.12 no.1
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• pp.16-24
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• 2009

In this study, fatigue crack growth rate of a cracked railway bogie frame under variable amplitude loading is predicted by applying linear elastic fracture mechanics. For this purpose, we find the critical points by reference surveying on cracked railway bogie frames. And we make an effective load history by synthesizing the dynamic load measured from the critical points of railway bogie frame during commercial line operation and the static load calculated from structural analysis. Crack growth analyses are performed at the 3 critical points under the commercial operation loading condition by assuming an initial crack size as 40 mm. and the results are compared with the experimental results from Japanese railway bogie frame crack growth case. From the analysis results, we find that around 500,000 km operating distance is necessary to bring crack growth from the initial crack to unstable crack. And it takes around 3.8 normal operating years. We conclude that it is enough time to detect the crack between normal maintenance period.

• Journal of Forest and Environmental Science
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• v.31 no.3
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• pp.235-240
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• 2015

Zelkova serrata is an important hardwood species for the timber industry in Japan. Tree breeding programs for this species have mainly focused on growth characteristics such as stem diameter (D), tree height (TH), stem form, and branching. In order to fulfill timber industry needs, wood quality improvement should be included in the tree breeding program of this species. In the present study, growth characteristics, such as D and TH, and the stress-wave velocity (SWV), which is highly correlated with Young's modulus of wood, were measured for 20-year-old Z. serrata from eight half-sib families planted in a progeny test site with three different initial spacings. Significant differences in all the measured characteristics were found among the eight half-sib families. The variance components of the half-sib families for D, TH, and SWV were 27.2%, 47.3%, and 33.5%, respectively. These results indicate that all the measured characteristics of this species could be improved by tree breeding programs. In addition, only low correlation coefficients were obtained between the growth characteristics and SWV, indicating that extensive selection on SWV in tree breeding programs may not always lead to a reduction in yield volume.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.2
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• pp.207-212
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• 2000

Two experiments were conducted to investigate the effect of different lupin kernel levels on growth performance and carcass characteristics of growing and finishing pigs. In experiment 1, a total of 54 barrows and 54 growing gilts, with an average initial body weight of $24.7{\pm}0.38kg$, was used to determine the effect of different lupin kernel levels (0, 10% and 20%; Control, LK10 and LK20, respectively) in the diets on growth performance with a $3{\times}3$ randomized complete block design for 35 days. There were no significant differences in average daily gain (ADG), average daily feed intake (ADFI) and feed:gain among treatments. In experiment 2, a total of 54 barrows and 36 finishing gilts, with an average initial body weight of $63.0{\pm}0.56kg$, was used to determine the effect of different lupin kernel levels (0, 15% and 30%; Control, LK15 and LK30, respectively) in the diets on growth performance and carcass characteristics with a $3{\times}3$ randomized complete block design for 63 days. LK30 decreased ADG and ADFI compared with the Control and LK15 (p<0.05). However, LK30 tended to improve feed:gain compared with the Control and LK15. And LK15 did not differ from the Control in ADG, ADFI and feed:gain. With inclusion of lupin kernel in the finishing diet, backfat thickness increased (p<0.01) and carcass grade tended to be improved compared with the Control.

• Journal of the Korean Society of Safety
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• v.5 no.1
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• pp.19-29
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• 1990

The objective of this paper is to investigate the effect of residual stresses on the $\Delta$K$\sub$th/ and fatigue crack growth behavior of butt weldments. For this purpose, transverse butt sutmerged arc welding was performed on SM50A steel plate and CT(compact tension) specimens which loading direction is perpendicular to weld bead were selected. Welding residual stresses distribution on the specimen was determined by hole drilling method. The case of crack located parallel to weld bead, the states of as weld and PWHT, $\Delta$K$\sub$th/ of specimens(HAZ, weld zone) was higher than that of the base metal probably because of the compressive residual stresses of crack tip. In low $\Delta$K region, it is estimated that the effects of residual stresses for da/dN are great. In region II, the da/dN of weldments in as weld state was lower than that of the base metal. Though da/dN of Weldments in PWHT state was similar to that of the base metal. The constant of power law, m in two states consisted with the base metal. Therefore , it is estimated that the value of m is not affected by residual stresses. Fatigue crack growth behavior of weldments consisted with the base metal considering the effective stress intensity factor range($\Delta$K$\sub$eff/) included the effect of initial residual stress(Kres). Thus, we can predict the fatigue crack growth behavior of weldment by knowing the distribution of initial residual stress at the crack tip.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.11
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• pp.1588-1594
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• 2012

An 8-wk experiment was conducted to evaluate the effect of replacing fish meal (FM) with soy protein isolate (SPI) on the growth, digestive enzyme activity and serum biochemical parameters of juvenile Amur sturgeon (Acipenser schrenckii). SPI was used to replace 0, 25, 50, 62.5, 75, 87.5, 100% of dietary FM and 100% replacement supplemented crystalline amino acid. Healthy sturgeon with an average initial weight of $26.38{\pm}0.24$ g were randomly assigned to 24 aquaria (8 treatments with triplicates each) at an initial stocking density of 11 fish per aquarium and cultured for 8 wks. The results showed that 75.00% or more substitution resulted in a poor weight gain rate, feed conversion ratio and survival rate compared to that of fish fed the control diet (p<0.05), whereas no significant differences were observed between diets of 25.00% to 62.50% substitution. Protease, lipase and amylase activity in foregut, mid-gut and hindgut were significantly (p<0.05) decreased by diets where SPI replacement levels were 62.50% or more. Levels of serum total protein (TP) and globulin decreased significantly from 21.03, 10.34 to 14.05, 5.63 g/L with the increasing dietary SPI (p<0.05), but alkaline phosphatase activity significantly increased (p<0.05). In addition, supplemental crystalline amino acid in the FM absence diet did not improve growth performance, intestine digestive enzyme activities and serum biochemical parameters. In conclusion, the results from this study showed adverse effects of inclusion of SPI in diets on growth performance, feed utilization and serum biochemical parameters in juvenile Amur sturgeon. Based on WGR and replacement ratio presented in this report, a 57.64% replacement level was recommended.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.5
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• pp.671-677
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• 2011

A hyperthermophilic archaeon, $Thermococcus$ $onnurineus$ NA1 was studied to investigate its fermentation characteristics using various carbon sources including formate, maltose and carbon monoxide during the anaerobic batch cultivation at $80^{\circ}C$. Formate was the best carbon source for cell growth and hydrogen production among others. In the batch culture on formate, it was found that the cell concentration increased exponentially by 12 hrs of culture, after which the cell growth and formate consumption was retarded. Hydrogen production was continued more than 24 hrs although the cell growth was ceased at 18 hrs. Hydrogen production rate was directly correlated with the cell growth and formate degradation up to 18 hrs, and the average hydrogen production yield was 1.05 mole-$H_2$/mole-formate. Cell growth and hydrogen production were optimized at the initial pH 6-7, while inhibited at the initial pH lower than 5 and higher than 9.

• Korean Journal of Agricultural Science
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• v.47 no.2
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• pp.229-237
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• 2020

This study assessed the effects of a dietary non-genetically modified organism (non-GMO) source on growth performance and nutrient digestibility of grower-finisher pigs. The dietary treatments were 1) rice-soybean meal-based control diet and 2) rice and non-GMO soybean meal-based diet. In the experiment 1, 60 growing pigs (initial body weight [BW] = 23.76 ± 3.42 kg) were randomly assigned to 1 of 2 dietary treatments with 6 pigs·pen^-1 (5 replications) for 6 weeks. In experiment 2, 48 finishing pigs (initial BW = 64.31 ± 6.17 kg) were randomly assigned to 1 of 2 treatment groups with 4 pigs·pen^-1 (6 replications) for 6 weeks. Measurements were the average daily gain (ADG), average daily feed intake (ADFI), gain-to-feed ratio (G : F), and nutrient digestibility. The growth performance was measured at the beginning and end of each period. The apparent total tract digestibility (ATTD) was determined by chromium oxide as an indigestible marker during the last 7 days of each experiment. During the grower period, pigs fed the diet containing the non-GMO soybean meal had a higher (p < 0.05) ADFI than those fed the control diet; however, there were no differences between the dietary treatments in the ADG, G : F, and ATTD. Moreover, the dietary treatments did not affect the ATTD and growth performance of the finishing pigs. In conclusion, the inclusion of non-GMO soybean meal in the diet had no negative effects on the growth rate and nutrient digestibility, indicating that non-GMO soybean meal can be used in diet formulations with other feed ingredients and be a substitute for conventional soybean meal.

• Korean Journal of Agricultural Science
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• v.47 no.2
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• pp.275-282
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• 2020

Two experiments were conducted to examine the effects of the difference in energy concentration in diets on performance and nutrient digestibility of growing-finishing pigs. The experimental diets were as follows: 1) a normal energy level corn-soybean meal-based diet (CON) and 2) high-energy diet compared with the CON (HE). Pigs had free access to their feed and water ad labium for 6 weeks during each experimental period. In experiment 1, 60 growing pigs (initial body weight [BW] of 23.85 kg) were randomly allotted to 2 treatment groups with 5 replications (6 pigs·pen^-1). In experiment 2, 48 finishing pigs (initial BW = 65.13 kg) were randomly assigned to 2 treatment groups with 6 replications (4 pigs·pen^-1). The growth performance was measured at the beginning and end of each period. The apparent total tract digestibility (ATTD) was determined by chromium oxide as an indigestible marker during the last 7 days of each experiment. In experiment 1, the dietary treatments did not affect the growth performance and ATTD of energy and nutrients. In experiment 2, no differences in growth performance were observed for pigs fed CON and HE throughout the experimental period. Additionally, dietary treatments did not affect the ATTD. In conclusion, the high energy content in diets for the growing-finishing period had no effect on the growth performance or digestibility, indicating that a wide range of energy content changes in diets would be required to affect the performance and digestibility of grower-finisher pigs. It is also necessary to understand the characteristics of components used to adjust the dietary energy concentration.

• Animal Bioscience
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• v.34 no.2
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• pp.233-242
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• 2021

Objective: The aim of this study was to determine the effect of pineapple cannery by-product (PCB) level on the growth performance and carcass characteristics of finishing Hanwoo steers. Methods: The feeding stage was divided into early and late finishing stages. A total of 60 castrated Hanwoo steers (13.9±0.8 months old, 418.8±36.5 kg initial body weight [BW]) were blocked by initial BW and then randomly allotted into 12 pens (five head/pen). The pens were randomly assigned to control (CONT), low PCB (LPCB), or high PCB (HPCB) treatments. These diets contained 0%, 1.5%, or 3.0% of PCB (on a dry matter [DM] basis; as-fed basis was 0%, 10.6%, or 21.2%), respectively. Results: For the early finishing stage, body weight gain (BWG) and average daily gain (ADG) of the CONT and LPCB feeding groups were greater (p<0.05) than those of the HPCB feeding group. In addition, there were linear and quadratic effects on BWG and ADG with increasing dietary PCB level (p<0.05). The gain to feed (G:F) ratio tends to quadratically decrease with an increasing PCB level in the early finishing stage (p = 0.076). Growth performances of late finishing stage were not affected by PCB level. The marbling score of the LPCB feeding group was similar to that of the CONT feeding group. However, there was a linear decrease (p< 0.05) in marbling score and quality grade among treatments as PCB was increased in the diet. In the longissimus muscle free amino acid profile, histidine composition increased linearly (p<0.05) with an increasing level of PCB. Conclusion: The level of PCB 1.5% DM in diet can be used for finishing steers without any adverse effects on growth and carcass performances. However, there were some negative effects on growth and carcass performance in the HPCB feeding group.