• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2000년도 추계학술대회 논문집
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• pp.37-41
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• 2000

Extruded Profiles of Aluminum alloys have been widely used as parts and frames in mechanical and construction structures. Nowadays, mechanical processing of extruded Al alloy profiles is often employed for various industrial applications. Especially, the bending process is more and more applied and the process is greatly influenced by the distributed mechanical properties in the extruded profiles. Due to large reduction of area or extrusion ratio in ordinary production of extruded profiles, anisotropy is naturally induced by large severe deformation during the extrusion process. Therefore, the anisotropy properties play a great role in the bending process, as a post processing of extruded profiles and errors will be involved when the extruded profiles are treated as isotropic material, ignoring the induced anisotropy in the thin-walled extruded product. In the present work, the anisotropic material change is simulated, as a simplified method, employing Barlats six-component yield criterion in the rigid-plastic finite element method. Finite element computations are carried out for extrusion of a thin-walled part.

• Preventive Nutrition and Food Science
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• 제21권3호
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• pp.271-280
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• 2016

The effects of $CO_2$ injection and barrel temperatures on the physiochemical and antioxidant properties of extruded cereals (sorghum, barley, oats, and millet) were studied. Extrusion was carried out using a twin-screw extruder at different barrel temperatures (80, 110, and $140^{\circ}C$), $CO_2$ injection (0 and 500 mL/min), screw speed of 200 rpm, and moisture content of 25%. Extrusion significantly increased the total flavonoid content (TFC) of extruded oats, and ${\beta}$-glucan and protein digestibility (PD) of extruded barley and oats. In contrast, there were significant reductions in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, PD of extruded sorghum and millet, as well as resistant starch (RS) of extruded sorghum and barley, and total phenolic content (TPC) of all extrudates, except extruded millet. At a barrel temperature of $140^{\circ}C$, TPC in extruded barley was significantly increased, and there was also an increase in DPPH and PD in extruded millet with or without $CO_2$ injection. In contrast, at a barrel temperature of $140^{\circ}C$, the TPC of extruded sorghum decreased, TFC of extruded oats decreased, and at a barrel temperature of $110^{\circ}C$, PD of extruded sorghum without $CO_2$ decreased. Some physical properties [expansion ratio (ER), specific length, piece density, color, and water absorption index] of the extrudates were significantly affected by the increase in barrel temperature. The $CO_2$ injection significantly affected some physical properties (ER, specific length, piece density, water solubility index, and water absorption index), TPC, DPPH, ${\beta}$-glucan, and PD. In conclusion, extruded barley and millet had higher potential for making value added cereal-based foods than the other cereals.

• 한국건축시공학회지
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• 제12권6호
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• pp.575-585
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• 2012

The extruded cement panel, which has many advantages as a prefabricated method, has been limited in its application due to its low fire-resistance. However, an extruded cement panel produced by mixing a-hemihydrate gypsum offers dramatically improved fire-resistance and is expected to have wide-ranging applications in the construction sector as an interior material or partition wall between housing units. Sound insulation performance is very important for the partition wall between housing units. In this study, the sound insulation performance of the extruded cement panel produced through the mixture of a-hemihydrate gypsum is reviewed in order to determine its usability for a partition wall between housing units and for interior materials. Through the review it was found that the wall formed using the extruded cement panels produced by mixing the a-hemihydrate gypsum have ★★★ class in sound insulation test, equal or superior compared with the other two types of extruded cement panel walls currently available in the market.

• 한국건축시공학회지
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• 제12권6호
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• pp.586-595
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• 2012

While the extruded cement panel has many advantages compared to drywall, it has limited applicability in buildings due to its low fire resistance. However, an extruded panel in which the fire resistance has been dramatically enhanced through the addition of a-hemihydrate gypsum is expected to become widely applied as a partition wall or interior material for buildings. To ensure its applicability, certain safety requirements for use, such as the leaning load by residents, the impact by indoor articles, and the fire, need to be taken into consideration. The purpose of this study is to review the impact load resistance, horizontal load resistance, and fire resistance as required safety properties for the partition wall and interior materials of the extruded panel that includes a-hemihydrate gypsum. The results of this study show that the impact load resistance of the extruded panel that includes a-hemihydrate gypsum achieves SD grade for industrial buildings, and the horizontal impact load resistance achieves HD grade for public buildings. In addition, it provides fire-resistance for approximately 7 minutes longer than the existing extruded cement panel. Based on this result, it is confirmed the extruded panel incorporating a-hemihydrate gypsum has adequate safety properties for use as partition wall or interior material.

• Journal of Biosystems Engineering
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• 제35권1호
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• pp.64-68
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• 2010

Cattle feedlot manure could be used effectively as the solid fuel for heating of agricultural facilities. Therefore, this study was carried out to investigate the thermal and physicochemical characteristics of solid fuel extruded with cattle feedlot manure. Calorific values of the solid fuel extruded with cattle feedlot manure, which was dried to the moisture contents of 0.0% (w.b) and 35.0% (w.b,) were 14,906 kJ/kg and 11,797 kJ/kg, respectively. Calorific value of extruded solid fuel was linearly decreased with the increase of moisture content. The first, second, and third reaction point during thermal pyrolysis of solid fuels extruded with cattle feedlot manure was investigated as $108.1^{\circ}C$, $312.2^{\circ}C$, and $459.4^{\circ}C$, respectively. The maximum reaction point was presented at the temperature of $312.2^{\circ}C$. Weight loss of extruded cattle feedlot manure during thermal pyrolysis until $600^{\circ}C$ was reached to about 60%. Volume decrease of initial extruded cattle feedlot manure was 61% during drying for the use as solid fuel. Maximum strength of extruded cattle feedlot manure, which was dried as the moisture content of 10% (w.b.) was 41,9150 N/$m^2$. Ignition gas analysis of extruded cattle feedlot manure presented that it has small amount of $NO_x$ and $SO_x$. It was shown that dried cattle feedlot manure had main components of C and O including small amount of Mg, Si, and Ca.

• 한국식품조리과학회지
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• 제28권6호
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• pp.813-820
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• 2012

To develop the high quality gluten-free rice products with health functionality and desirable texture with moistness, the physicochemical properties of extruded rice flours prepared from the mixture of germinated brown and white rices were investigated. The domestic organic Samgwangbyeo was used to make white and germinated brown rices. White rice (WR) was dried after soaked for 6 h at $15{\pm}3^{\circ}C$ and mixed with germinated brown rice (GBR) with different mixing ratios (100:0, 75:25, 50:50, 25:75, 0:100). The operating conditions of twin screw extruder were 250 rpm of screw speed, $120^{\circ}C$ of barrel temperature, and 25% moisture content of rice flour. The ash, crude protein and crude lipid contents were significantly different (p<0.05) and those of extruded GBR were the highest values, but those of extruded WR were the lowest. The color difference of extruded WR based on white plate showed the lowest among them. The water binding capacity (334.16%), swelling power (8.83 g/g), solubility (33.13%), and total starch (79.50%) were the lowest in extruded GBR. The viscosities of all extruded rice flours by RVA were maintained during heating. The peak and total setback viscosities of extruded rice flours ranged 127-352 and 58.0-85.5 cP, respectively. The novel food biomaterial from germinated brown rice as well as white rice was developed by twin screw extruder. The extruded rice flours control the moistness to improve the texture and also have functional materials, dietary fiber, GABA, and ferulic acid, etc to increase quality of gluten free rice products.

• Asian-Australasian Journal of Animal Sciences
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• 제18권7호
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• pp.980-989
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• 2005

The influence of treated, extruded, partially expelled soybean meals as undegradable protein and bypass fat sources on lactation performance and ruminal fermentation of dairy cows was studied. Experiment 1: nine cows were used in a replicated 3${\times}$3 Latin square design with each period being 3 wk in duration. Cows were fed 440 g/kg forage and 560 g/kg grain diet with one of three extruded soybean meals fed at 110 g/kg of the diet. The 3 soybean meals were 1) twice-extruded soybean meal (ESM; as a control); 2) lignosulfonate-treated, twice-extruded soybean meal (LSM); and 3) calcium oxide plus lignosulfonate-treated, twice extruded soybean meal (CLSM). Experiment 2: 3 ruminally cannulated cows were used in a 3${\times}$3 Latin square to study the treatment influence on ruminal fermentation characteristics. Feeding treated soybean meal to cows in LSM and CLSM treatments did not improve feed intake, milk yield, or milk composition except that cows fed the LSM and CLSM treatments produced less milk protein compared with the ESM treatment. The proportion of $C_{18:2}$ was greater in milk fat of cows fed CLSM compared with that of cows fed the ESM or LSM treatments. Ruminal pH, ammonia, and total volatile fatty acids were not affected by treatment. An increased proportion of $C_{18:2}$ in milk fat suggests that there is a potential use of calcium salts of fatty acids in protecting the lipid portion of extruded soybean meal and further research is needed to explore this potential with full-fat extruded soybeans not with extruded and partially oil expelled soybeans.

• 한국미생물·생명공학회지
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• 제19권5호
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• pp.514-520
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• 1991

Extrusion시켜 구조변형시킨 전분(질)을 기질로 cyclodextrin glucanotransferse(CGTase)를 활용하여 액화과정을 거치지 않고 직접 cyclodextrin을 합성하는 불용성 extrusion된 전분-수용성 CGTase로 구성된 불균일상 효소반응계에 관하여 연구하였다. Extrusion된 전분을 기질로 이용할 경우 기존의 액화전분을 기질로하는 균일상 효소반응계에서 보다 현저히 증가된 CD 농도, 수율 그리고 합성속도를 얻을 수 있었으며, extrusion된 전분 기질농도가 100g/l일 때 CD생성량과 수율은 각각 54g/l와 0.54였다.

• 소성∙가공
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• 제31권5호
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• pp.253-260
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• 2022

In this study, the microstructural characteristics of a high-speed-extruded Mg-5Bi-3Al (BA53) alloy and its tensile, compressive, and high-cycle fatigue properties are investigated. The BA53 alloy is successfully extruded at a die-exit speed of 16.6 m/min without any hot cracking using a large-scale extruder for mass production. The homogenized BA53 billet has a large grain size of ~900 ㎛ and it contains fine and coarse Mg₃Bi₂ particles. The extruded BA53 alloy has a fully recrystallized microstructure with an average grain size of 33.8 ㎛ owing to the occurrence of complete dynamic recrystallization during high-speed extrusion. In addition, the extruded BA53 alloy contains numerous fine lath-type Mg₃Bi₂ particles, which are formed through static precipitation during air cooling after exiting the extrusion die. The extruded BA53 alloy has a high tensile yield strength of 175.1 MPa and ultimate tensile strength of 244.4 MPa, which are mainly attributed to the relative fine grain size and numerous fine particles. The compressive yield strength (93.4 MPa) of the extruded BA53 alloy is lower than its tensile yield strength, resulting in a tension-compression yield asymmetry of 0.53. High-cycle fatigue test results reveal that the extruded BA53 alloy has a fatigue strength of 110 MPa and fatigue cracks initiate at the surface of fatigue test specimens, indicating that the Mg₃Bi₂ particles do not act as fatigue crack initiation sites. Furthermore, the extruded BA53 alloy exhibits a higher fatigue ratio of 0.45 than other commercial extruded Mg-Al-Zn-based alloys.

• Animal Bioscience
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• 제36권10호
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• pp.1546-1557
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• 2023

Objective: The present study aimed to evaluate the effects of extruded and unextruded feeding on the performance, milk composition, digestibility and ruminal fermentation of dairy cows through a meta-analysis. Methods: The database was compiled from 53 studies in Scopus and PubMed. The data were analyzed using a random effects model in OpenMEE software. Extruded feed was grouped as the experiment group while and the others as control group. The bias of publication in the main parameter of dairy performance was evaluated by a funnel plot. Results: The result showed that extruded feed enhanced the milk yield, dry matter and crude protein digestibility, butyrate and valerate acid production (p<0.05). Meanwhile, the extruded feed significantly decreased the milk fat and protein concentration (p<0.05). Also, the iso-butyrate and iso-valerate in unextruded feeding was significantly higher than the extruded feed (p<0.05). Conclusion: It was concluded from the meta-analysis that extruded feed effectively improved the milk production and milk lactose concentration, dry matter and protein digestibility, but not the milk fat and protein concentration.