• Transactions of Materials Processing
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• v.31 no.6
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• pp.344-350
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• 2022

Extruded Mg-Bi binary alloys are known to have an undesirable bimodal grain structure containing a large amount of coarse unrecrystallized grains. Accordingly, to improve the microstructural homogeneity of extruded Mg-Bi alloys, it is necessary to promote the dynamic recrystallization (DRX) behavior during hot extrusion. An effective way to promote DRX is an increase in nucleation sites for DRX through a pre-deformation process before extrusion, such as cold pre-forging and hot pre-compression. However, the application of these pre-deformation processes increases the cost of final extruded Mg products because of an increase in energy consumption and decrease in productivity. Therefore, a low-cost new continuous process with high productivity is required to improve the microstructural homogeneity and mechanical properties of extruded Mg alloys without a drastic increase in the entire process cost. This study proposes a new extrusion method using an extrusion billet with a truncated cone shape (i.e., tapered billet) instead of a conventional extrusion billet with a cylindrical shape. When the hot extrusion of a Mg-5Bi alloy is conducted using the tapered billet, the DRX behavior during extrusion is considerably promoted. The DRX fraction and average grain size of the extruded alloy significantly increase and decrease from 65% to 91% and from 225 ㎛ to 49 ㎛, respectively. Consequently, the extruded Mg-5Bi alloy fabricated using the tapered billet has a finer homogeneous grain structure and higher tensile elongation than the extruded counterpart fabricated using the cylindrical billet.

• Design & Manufacturing
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• v.2 no.2
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• pp.43-47
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• 2008

This paper is concerned with the analysis of material flow characteristics of stepped rod forming. The analysis in this paper concentrated on the evaluation of the design parameters for deformation patterns of tube forming, load characteristics, extruded length, and die pressure. The design factors such as punch nose radius, die corner radius, friction factor, and punch face angle are involved in the simulation. The stepped rod forming is analyzed by using a commercial finite element code. This simulation makes use of stepped rod material and punch geometry on the basis of punch geometry recommended by International Cold Forging Group. As radius ratio is large, forming load was reduced but extruded length ratio was increased.

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.528-534
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• 2011

This study was conducted to investigate the changes in saponin content and antioxidant activity of crude ginseng and extruded ginseng by using different solvent extraction methods. Each of the fractions was first extracted by 80% ethanol followed by ether treatment to remove the lipid components. Water soluble components were separated by ethylacetate and water saturated butanol. Four fraction, including 80% ethanol, ethylacetate, butanol and water were obtained from crude and extruded ginsengs to analyze saponin content and antioxidant activity. Saponin content and antioxidant capacity of each of the four fractions were measured by LC/MS analysis and ORAC(Oxygen Radical Absorbance Capacity) assay, respectively. It was found that a major portion of saponin was present in ethyl acetate and water saturated butanol fractions. When extracted by 80% ethanol, ginsenoside Rb1 and Rg1 were mostly found in crude ginseng, while ginsenoside Re and Rb1 were detected in extruded ginseng. Even though Rh1 and Rg3 were found in a very small quantity in crude ginseng, there was a significant quantity of both in extruded ginseng when extracted by 80% ethanol. Similar tendency was also observed in extruded ginseng fraction when extracted with ethyl acetate and butanol. In crude ginseng, the level of Rg1 was the highest among other ginsenosides upon extraction by ethyl acetate, while Rh1 and Rg3 were predominantly found by employing similar solvent extraction in the extruded ginseng. Also, Rg1, Re and Rb1 were also found in the extruded ginseng with small quantity. Rg1, Re and Rb1 were found in crude ginseng by butanol extraction, while Rb1 and Re were extracted from the extruded ginseng. Overall, there was no difference in the saponin content between crude ginseng and extruded ginseng when extracted by butanol and water, but twice as much of saponin was obtained by 80% ethanol extraction and 6 times more saponin were obtained in ethyl acetate fraction in the extruded ginseng. Antioxidant capacity of crude ginseng as determined by ORAC assay was higher in 80% ethanol(high in many different kinds of biological compounds) and water saturated butanol(high in polar saponin) fractions than the ethyl acetate and water fractions. No difference in antioxidant capacity was observed between crude and extruded ginseng. However, antioxidant capacity of ethyl acetate and water fractions in extruded ginseng was significantly higher than crude ginseng($P$ >0.05). All the fractions in both, crude and extruded ginseng possessed antioxidant capacity and even water fractions that contained almost no saponin had some antioxidant capacity. While determining correlation coefficient between fractions in extruded ginseng by Pearson correlation, it was observed that 80% ethanol fraction was in correlation with ethyl acetate($P$ >0.01) and ethanol($P$ >0.001) and in the case of ethylacetate, correlation was observed only with butanol fraction($P$ >0.05).

• Korean Journal of Poultry Science
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• v.17 no.4
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• pp.284-295
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• 1990

Dietary levels of 0%, 0225%, 0.45% inorganic phosphorus in the form of tricalcium phosphate were included in two different experimental diets, which contains 40% of wheat bran with or without extrusion. It is to examine the effects of extruded wheat bran containing different Bevels of inorganic phosphorus on the performance of broiler chicks, including the nutrient availabilities, compared with that of the diet containing non－extruded wheat bran. The results are as follows； 1. Regardless dietary levels of inorganic phosphorus, the weight gain in general was higher for the groups fed non－extruded wheat bran but little significance was seen between the groups of extruded and the non－extruded. However, the effect of dietary inclusion of inorganic phosphorus on the weight gain was evident and the gain was higher in the groups receiving the higher levies of inorgainc phosphorus but failed to observe the significant difference between the added groups of 0.225% and 0.45% of inorganic phosphorus, suggesting that a considerable amount of phytin phosphorus in wheat bran is available to meet the requirement. 2. For the feed intake, there was a tendency for the groups fed extruded wheat bran consuming more feed, compared with that of the non－extruded but little significance was observed. This was also true between the groups of receiving 0.225% and 0.45% inorganic phosphorus t The feed efficiency was improved by the addition of inorgainc phosphorus, but failed to observe the significance between the added groups. 4. The dry matter digestibility was improved in proportion to increasing the levels of inorganic phosphorus for the both groups of extruded and the non－extruded This indicates that addition of extruded wheat bran has little effects on improving the digestibility. 5. Within the added groups of 0.225% and 0.45% inorganic phosphorus, the protein digestibility was increased with including the extruded wheat bran in the diet However, the effect on body weight gain was not evident. 6. The calcium and phosphorus content of tibia was shown the tendency of increasing with increasing the dietary levels of inorganic phosphorus but close correlation with dietary levels of inorganic phosphorus was not noted in tibia contents of calcium and phosphorus.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.8
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• pp.676-682
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• 2002

This paper has been made to investigate the thermal performance characteristics for the several types of heat sinks such as extruded heat sink, aluminum foam heat sink, layered heat sink. The various types heat sinks are prepared and tested for natural convection as well as forced convection. The experimental results for natural convection are compared to those for three types of heat sink so that the appropriate heat sink can be designed or chosen according to the heating conditions. The overall heat transfer performances for layered heat sink, extruded heat sink and aluminum foam heat sink are almost comparable to those under natural convection and forced convection. The forced convection of layered heat sink become 1.2 times as high as those of extruded heat sink, and the forced convection of extruded heat sink become 1.2 times as high as those of aluminum foam heat sink. This study shows that bar height, bar distance and number of bar for layered heat sink are important parameters, which have a serious influence on thermal performance for layered heat sinks.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.5 s.182
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• pp.51-58
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• 2006

The necessities for heightening fuel efficiency as well as lightweight design, lead to an increase of the use of aluminum alloys in the automobile industry. Extruded aluminum profile channels are used widely for the design of frame parts as lightweight assemblies, especially if a high stiffness is needed. While many applications can be realized with forming of hollow square-sectioned extruded profiles such as a stretch bending and a hydro-forming, some applications demand the use of a press bending which can be hardly found in the previous study. In this study, by introducing the use of a press bending into car sub-frames, the demands for higher accuracy as well as higher flexible method than the conventional methods will be satisfied. With respect to the design of sub-frames, the process planning was performed from the shape of a sub-frame product. The designed processes were analyzed by the commercial FEM code, DEFORM-3D. Forming dies for the each process were designed and prototypes of sub-frames were manufactured by the verified farming process. In addition, some of the important features of design parameters in the press bending were reviewed.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.402-408
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• 2007

This study was conducted in order to evaluate the antioxidant activity of extruded ginseng in different extracted fractions. Each of the fractions obtained from extruded ginseng and ginseng (control) were extracted with 80% ethanol, and then the lipophilic components were removed with ether while the hydrophilic components were separated with water-saturated butanol. Each of the 80% ethanol/butanol/water layers were collected and evaporated to acquire samples for tests of saponin content and antioxidant activity. The antioxidant activity of extruded ginseng fractions and ginseng fractions were determined via the oxygen radical absorbance capacity (ORAC) assay. Overall, the extruded ginseng samples harbored saponin contents of 2.2 (Rg1), 2.3 (Re), 1.2 (Rc), 1.3 (Rb2), and 2.2 (Rd) times that measured in the ginseng prior to extrusion. Antioxidant capacity was also higher, not only in the 80% ethanol/butanol which harbor a significant quantity of saponin, but also in the water fractions, which harbor relatively low quantities of saponin as compared to the control samples. All three of the fractions extracted from extruded ginseng evidence significantly higher antioxidant capacity than the controls (0.05

• Journal of Animal Science and Technology
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• v.57 no.7
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• pp.26.1-26.5
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• 2015

Background: Rice bran is a by-product of the rice-milling process, which remains largely underutilized; however, efficient processing treatments may improve its feeding value for chickens. This is of great economic and environmental importance, as this can lower the production costs, and offer an opportunity for valorization of a low-quality agricultural by-product, to a high-value feed source. Methods: This experiment was conducted to study the effect of extruded rice bran on performance and phosphorous (P) bioavailability in broiler chickens. In a completely randomized design, 200 seven-day-old broilers (Cobb 500) were allotted to five treatments with five replicates per treatment and 8 chicks per replicate, and fed with their respective diet during the starter (8 to 21 days) and grower (22 to 42 days) periods. Diets were a basal corn-soybean based diet (T1), or diets containing 20 % rice bran (T2), 30 % rice bran (T3), 20 % extruded rice bran (T4), or 30 % extruded rice bran (T5). Results: Birds feeding on T4 and T5 diets had a higher body weight gain and lower feed-to-gain ratio compared to those feeding on T2 and T3 diets (p < 0.05). Birds receiving diets containing extruded rice bran had higher total P availability and tibia ash content, as compared with those receiving diets containing un-extruded rice bran (p < 0.05). Relative weight of the pancreas was higher in birds receiving T2 and T3 diets. Conclusions: The results confirmed the beneficial effect of extrusion treatment of rice bran on performance and P availability in broilers. Up to 30 % extruded rice bran may be included in the broiler diet without apparent adverse effects on the performance.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.2
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• pp.200-206
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• 2000

Ninety nursery pigs were used in two metabolism experiments to determine the effects of roasting and extruding on the nutritional value of Williams 82 soybeans with (+K) and without (-K) gene expression for the Kunitz trypsin inhibitor. Treatments for both experiments were: 1) soybean meal; 2) +K roasted; 3) +K extruded; 4) -K roasted; and 5) -K extruded. Diets were the soybean preparations (96.5% of the diet) with only vitamins and minerals added as needed to meet or exceed NRC recommendations. Daily feed allowance was 5% of initial BW given as three equal meals. In Exp. 1, 50 weanling pigs (4.7 kg average BW and 21 d average age) were used. Apparent values for N digestibility (p<0.001), biological value (p<0.09), percentage N retention (p<0.05), GE digestibility (p<0.001) and percentage ME (p<0.001) were greater for pigs fed extruded soybeans than pigs fed roasted soybeans. Also, N digestibility (p<0.05), biological value (p<0.03) and percentage N retention (p<0.04) were greater for pigs fed -K soybeans than those fed +K soybeans. In Exp. 2, 40 pigs (9.7 kg average BW and 35 d average age) were allowed to adjust to the nursery environment before use in the experiment. In general, the pigs in Exp. 2 (i.e., the older pigs) had greater utilization of nutrients from all of the soybean products than the younger pigs used in Exp. 1. Digestibilities of DM, N and GE were greater (p<0.001) for pigs fed -K soybeans than those fed +K soybeans and extruded soybeans had greater digestibilities of DM, N and GE than roasted soybeans (p<0.001). Also, percentage N retention (p<0.01) and percentage ME (p<0.001) for pigs fed extruded soybeans were greater than for pigs fed roasted soybeans. In conclusion, extruded and -K soybeans were greater nutritional value than roasted and +K soybeans for 4.7 and 9.7 kg nursery pigs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.681-687
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• 2022

The government has implemented a policy to promote the use of extruded pellets in sustainable aquaculture by protecting fishery resources and managing the ocean environment. A survey on the production status and the cost of targeting olive flounder Paralichthys olivaceus culture farms in Jeju Island using extruded pellets was conducted. The survey results were used to examine the profitability and economic feasibility of the test farms, as well as the degree of increase in profitability and economic feasibility of the fish farms receiving government subsidies for employing extruded pellets. The economic feasibility was predicted through a sensitivity analysis of prices and production, which are the variable factors when of using the extruded pellets. Using the economic feasibility analysis, the average NPV (Net Present Value) and IRR (Internal Rate of Return) of sample farms were found to be KRW 5.8 billion and 8.9%, respectively. The result of the economic feasibility analysis of the government subsidy showed a maximum average of about 2.3 times higher NPV and a 3.8% increase in IRR in cases where government subsidies were received.