• Advances in Energy Research
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• 제3권3호
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• pp.181-194
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• 2015

In this work, an experimental study of the gasification on wood was carried out in downdraft type fixed bed Gasifier attached with 10 kW duel fuel diesel engine. The main objective of the study was to use wood as the biomass fuel for downdraft Gasifier and to evaluate the operating parameter of gasifier unit to predict its performance in terms of gas yield and cold gas efficiency. The influence of different biomass on fuel consumption rate, gas yield and cold gas efficiency was studied. Composition of producer gas was also detected for measuring the lower heating value of producer gas to select the feed stock so that optimum performance in the existing gasifier unit can be achieved. Under the experimental conditions, Lower heating value, of producer gas, cold gas efficiency and gas yields, using wood as a feed stock, are $4.85MJ/m^3$, 46.57% and $0.519m^3/kg$.

• 한국기계가공학회지
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• 제18권11호
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• pp.89-95
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• 2019

In this research, the effect of roughing on tool load through bottom-up machining is investigated through actual machining. Generally, through the use of high-speed machining technology, machining methods, such as general roughing, operate by deepening the cutting depth for as long as the tool is able to withstand it, giving a slower feed rate, less cutting depth, and faster feed. However, when the cutting depth is deep, there is a problem in that the stepped shape of the cutting area is increased (e.g., by the shaking of the tool or the chipping load). However, if the cutting is performed less, the cutting time becomes relatively long. To compensate for these drawbacks and extend the service life of the tool, economic efficiency needs to be secured.

• 한국정밀공학회지
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• 제24권6호
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• pp.51-57
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• 2007

Creep-feed grinding is an effective technology processes to increase the productivity and efficiency in form grinding. This method has, however, some problems which the progress of abrasive wear around the cutting edge is remarkable, grinding force become intense and burn marks on the ground surface occur frequently. In order to solve this problems, it is proposed in this study to dress the grinding wheel continuously during the grinding process. The purpose of this research is. therefore, that CNC creep-feed grinding machine which has a continuous dressing device developed and some grinding experiments for determination of dressing conditions carried out.

• 한국수산과학회지
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• 제49권5호
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• pp.683-688
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• 2016

The effects of dietary supplementing natural additives [yacon (YC), ginger (GG), and blueberry (BB)] on growth, feed utilization, and body composition of juvenile rockfish were compared to those of ethoxyquin (EQ), which is commonly used to prevent rancidity of fish feed. A total of 480 fish were distributed randomly into 12 50-L flow-through tanks (40 fish/tank). Four experimental diets were prepared: the control diet (Con) with 0.01% EQ, and the YC, GG and BB diets containing 1% YC, GG, and BB instead of wheat flour. Each diet was assigned randomly to triplicate tanks of fish, which were hand fed to satiation twice daily for 8 weeks. Weight gain of fish fed the YC diet was higher than that of fish fed all other diets. Feed efficiency (FE), protein efficiency ratio (PER), and protein retention (PR) in fish fed the YC diet were higher than those in fish fed the other diets. Whole-body chemical composition of the fish was affected by the additive sources. In conclusion, dietary supplementation with GG effectively improved weight gain and feed utilization (FE, PER, and PR) of juvenile rockfish.

• Nutrition Research and Practice
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• 제3권1호
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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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• 제17권8호
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• pp.1112-1117
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• 2004

This experiment was conducted to compare the effects of vitamin C supplemented in either feed or water on the performance and carcass characteristics of broilers during the hot season. For a 6 week feeding trial, a total of 330 broiler chicks (Ross, 4 d old, average 57 g BW) were alloted to five treatments. The treatments of vitamin C (VC) supplementation were 1) 0 ppm VC, 2) 10 ppm VC in feed, 3) 20 ppm VC in feed, 4) 5 ppm VC in water and 5) 10 ppm VC in water. During the starter phase (0-3 week), chicks on non-supplemented group grew slower (p<0.01) than the supplemented ones, and a similar trend was also noted during finisher stage and the overall stage. Feed intake was significantly (p<0.05) higher in supplemented groups and higher when fed in feed as compared with water during all stages. But feed conversion efficiency was significantly improved in non-supplemented groups compared to supplemented ones in finisher and overall stage. The digestibility of gross energy and ether extract was significantly (p<0.05) higher during starter phase in supplemented, given in feed, and at higher levels as compared with non-supplemented, given in water, and at lower levels, respectively. The bone resistance was significantly (p<0.05) higher in supplemented, supplied in feed groups as compared with their counterparts. Except breast meat, the dressing percentage and abdominal fat were also higher in supplemented group and the dressing percentage was significantly (p<0.05) higher in VC supplemented in feed as to water, but no effect of supplementation was noticed on meat color when compared between the methods of feeding (feed vs. water). The levels of VC in plasma and liver increased linearly, as the level of supplementation both in feed and water increased and it was significantly (p<0.05) higher in feed group as compared with water group. It can be concluded that, retention and availability of vitamin C in feed was higher than those in water, and supplementation of VC during summer was beneficial for poultry.

• Asian-Australasian Journal of Animal Sciences
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• 제9권3호
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• pp.309-313
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• 1996

This experiment was carried out to investigate the effect of rumen-protected lysine (RPLys) on growth rate, feed efficiency and plasma amino acid concentrations in sheep. RPLys was supplemented at the level of 0% ($T_1$), 0.2% ($T_2$) and 0.4% ($T_3$) of total DMI with 24 sheep in a 56 day feeding trial. The results are summarized as follows: 1. live weight gain of sheep in groups $T_1$, $T_2$ and $T_3$ was 219, 216 and 244 g/d, and was significantly (p < 0.05) higher for $T_3$ through the entire experiment. 2. Feed intake was not affected by RPLys supplementation. 3. The group fed $T_3$ had a significantly (p < 0.05) better feed efficiency than the groups fed $T_1$ and $T_3$. The response of $T_3$ was higher in growing period II of feeding low protein basal diet than in period I. 4. Plasma lysine concentrations tended to be higher with supplementing RPLys, but there were no differences between $T_2$ and $T_3$. 5. Supplementing RPLys in the diets increased plasma concentrations of arginine, asparagines, threonine, serine, valine and leucine compared with sheep receiving no RPLys. In contrast, plasma histidine was lower in sheep fed the supplementing RPLys than fed the diet $T_1$ with significant (p < 0.05) difference.

• Asian-Australasian Journal of Animal Sciences
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• 제30권2호
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• pp.198-205
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• 2017

Objective: This study aimed to investigate the effects of single or/and double strains of probiotic supplement on feed efficiency, growth performance, and microbial population in distal gastrointestinal tract (GIT) of weaning rabbits. Methods: Sixty-four weaning (28 days old) New Zealand White rabbits were randomly distributed into four groups with treatments including: basal diet without probiotic supplement (control) or supplemented as follows: $1{\times}10^6cfu/g$ B. subtilis (BS group), $1{\times}10^7cfu/g$ L. acidophilus (LA group), or $0.5{\times}10^6cfu/g$ B. subtilis plus $0.5{\times}10^7cfu/g$ L. acidophilus (BL group). During the research, the male and female rabbits were fed separately. Body weight of the rabbits was recorded at 28, 42, and 70 d of age. Results: There was an increase (p<0.05) in body weight gain for the LA group at 42 d. Rabbits fed BL responsed with a greater growth (p<0.05) and better feed conversion ratio (p<0.05) than those fed with no probiotic. Digestibility coefficients of dry matter, organic matter, crude protein, neutral detergent fiber, and gross energy were higher (p<0.05) in LA and BL groups than those in the control group. Male rabbits had higher (p<0.05) Bacilli spp. and Coliformis spp. in the ileum than female rabbits. Rabbits supplemented with BS had greater (p<0.05) numbers of bacilli in all intestinal segments than those receiving no probiotic, whereas intestinal Lactobacilli populations were greater (p<0.001) in the LA and BL diets compared to control. Average intestinal coliform populations were lowest (p<0.05) in the rabbits supplemented with LA as compared to those fed the control and BS. Conclusion: Supplementation of L. acidophilus alone or in combination with B. subtilis at a half of dose could enhance number of gut beneficial bacteria populations, nutrient digestibility, cecal fermentation, feed efficiency, and growth performance, but rabbits receiving only B. subtilis alone were not different from the controls without probiotic.

• Asian-Australasian Journal of Animal Sciences
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• 제27권9호
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• pp.1303-1310
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• 2014

A 12 week growth study was carried out to investigate the supplemental effects of dietary garlic powder (GP) on growth, feed utilization and whole body composition changes of fingerling sterlet sturgeon Acipenser ruthenus (averaging weight, 5.5 g). Following a 24-h fasting, 540 fish were randomly distributed to each of 18 tanks (30 fish/tank) under a semi-recirculation freshwater system. The GP of 0.5% (GP0.5), 1% (GP1), 1.5% (GP1.5), 2% (GP2) and 3% (GP3) was added to the control diet (GP0) containing 43% protein and 16% lipid. After the feeding trial, weight gain (WG) of fish fed GP1.5, GP2 and GP3 were significantly higher (p<0.05) than those of fish fed GP0, GP0.5 and GP1. Feed efficiency and specific growth rate (SGR) showed a similar trend to WG. Protein efficiency ratio of fish fed GP1.5, GP2, and GP3 were significantly higher (p<0.05) than those of fish groups fed the other diets. A significant difference (p<0.05) was found in whole body composition (moisture, crude protein, crude lipid, ash, and fiber) of fish at the end of the experiment. Significantly higher (p<0.05) protein and lipid retention efficiencies (PRE and LRE) were also found in GP1.5, GP2, and GP3 groups. Broken-line regression model analysis and second order polynomial regression model analysis relation on the basis of SGR and WG indicated that the dietary optimal GP level could be greater than 1.77% and 1.79%, but less than 2.95% and 3.18% in fingerling sterlet sturgeon. The present study suggested that dietary GP for fingerling sterlet sturgeon could positively affect growth performance and protein retention.

• Korean Journal of Acupuncture
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• 제21권1호
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• pp.51-60
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• 2004

Objectives : This research was performed to investigate the effect of herbal acupuncture(Ephedra sinica and Green tea) at Umnungchon(SP9) and Pungnyung(ST40) on weight gain, food intakes, food efficiency ratios, HDL-cholesterol, triglyceride, free fatty acid on rats fed high fat diet for 5weeks. Methods : Experimental groups were divided into normal group(Sham), high fat diet group(Con), high fat diet and Ephedra sinica-herbal acupuncture in SP9 ST40 treated group(ES), high fat diet and Green tea-herbal acupuncture in SP9 ST40 treated group (GT), high fat diet and Ephedra sinica+Green tea-herbal acupuncture in SP9 ST40 treated group(ES+GT). Herbal acupuncture was bilaterally treated at the level of 19.125mg/ml per 2 days during 5 weeks. Results : Body weight, feed intake and feed efficiency ratio were decreased in Sham, ES, ES+GT, compared with control group. The level of serum HDL-cholesterol was increased in sham, tender to increase in ES, ES+GT. The change on that of serum triglyceride was decreased in sham, ES, ES+GT and free fatty acid was decrease in sham, ES+GT. Conclusions : Ephedra sinica with Green tea-herbal acupuncture in SP9 ST40 can control the Body weight, feed intake and feed efficiency ratio, HDL-cholesterol, triglyceride, free fatty acid.