• Advances in concrete construction
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• v.15 no.2
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• pp.85-96
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• 2023

The characteristics of self-compacting concrete (SCC) made with fly ash and reinforced with polyester fibers were investigated in this research. Polyester fibers of 12 mm long and 15 micrometer diameters were utilized in M40 grade SCC mixtures at five different volume fractions 0.025%, 0.05%, 0.075%, 0.1%, 0.3% as a fiber reinforcement. To understand the influence of polyester fibers on passing ability, flowability, segregate resistance the J ring, L box, V funnel, slump flow and U box tests were performed. Polyester fibers have a direct influence, with a maximum of 0.075% polyester fibers producing excellent characteristics. ANN models were constructed using the testing data as inputs to anticipate the fresh and hardened characteristics as targeted outputs. The research revealed that R² values ranging from 0.900 to 0.997 appears to be a good correlation. The performance of ANN models and regression models for predicting the new characteristics of SCC is also evaluated.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.12
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• pp.1975-1984
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• 2020

Objective: The study was conducted to determine the effects of body weight (BW) and fiber sources on nutrient digestibility, fiber fermentation and short chain fatty acids (SCFA) concentration in different intestinal segments of growing pigs fed high-fiber diets. Methods: Nine barrows with initial BW of 25.17±0.73 kg and 9 barrows with initial BW of 63.47±2.18 kg were allotted to a duplicate 9×2 Youden Square design with 3 dietary treatments and 2 periods. The dietary treatments were formulated with 3 different high-fiber ingredients: corn bran, sugar beet pulp, and soybean hulls, respectively. Each diet was fed to 3 barrows with different stage of BW in each period. Results: There were no differences in the apparent ileal digestibility (AID) of most nutrients between pigs at different BW stages. Pigs at 60 kg had greater (p<0.05) apparent total tract digestibility (ATTD) of total dietary fiber (TDF), soluble dietary fiber (SDF) and insoluble dietary fiber (IDF), and had greater (p<0.05) hindgut disappearance of IDF and cellulose than pigs at 25 kg. The acetate, propionate and total SCFA concentrations in ileal digesta and feces of pigs at 60 kg were greater (p<0.05) than those of pigs at 25 kg. In addition, fiber sources affected (p<0.05) the AID of gross energy (GE), organic matter (OM), ether extract (EE), crude protein, SDF and hemicellulose, the hindgut disappearance and ATTD of dietary fiber components, the lactate and propionate concentrations in ileal digesta and the butyrate, valerate and total SCFA concentrations in feces. There were interactions (p<0.05) between BW and fiber sources on the AID of GE, OM, EE, SDF, hemicellulose, the ATTD of EE, TDF, and IDF, and the hindgut disappearance of SDF and hemicellulose. Conclusion: Increasing BW mainly improved the digestibility of dietary fiber fractions, and the dietary fiber sources influenced the digestibility of almost all the dietary nutrients in growing pigs.

• Journal of Nutrition and Health
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• v.28 no.1
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• pp.5-14
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• 1995

The present study was performed to investigate the effect of cereal fiber on lipid concentration of liver and serum in rats. Male Sprague-Dawley rats weighing 180$\pm$4g were divided into five groups by completely randomized block design : R, BR, B, W, and F. Each group fed a diet containing 0.7% cholesterol and a kind of cereal among rice(R), brown rice(BR), barley(B), whole wheat(W), and wheat flour(F) for 5 weeks. The results were summarized as follow : 1) Food intake. weight gain and feed efficiency ratio were not significantly different among the groups. 2) Fecal wet weight and dry weight were significantly higher in W group which fed the most amount of IDF(insoluble dietary fiber). 3) The weight of large intestine was significantly heavier in the W group compared to the others. But the weights of liver, stomach and small intestine were not significantly different among the groups. 4) Total lipid. triglyceride(TG) and total cholesterol(TC) content in liver were significantly different among the groups. The values were the lowest in the B group whose intake of SDF(soluble dietary fiber) was the highest 5) TC content in serum was not significantly different among the groups. TG content in serum was significantly lower in the rest groups than in the R group. HDL-c and free-c content in serum were significantly higher in the B group than in the rest groups. HDL-c/LDL-c, free-c/ester-c ratio were the highest in the B group but not significant. Above results show that the dietary fiber contained in cereals has physiological effects and they are different depending on fractions, IDF and SDF.

• KIEAE Journal
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• v.15 no.4
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• pp.45-52
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• 2015

Purpose: Foam concrete is the concrete that contains large amount of air voids inside. In general, the density of foam concrete depends on parameters like water/binder ratio, foam volume, aggregate and pozzolan content, etc. Method: In this study, the effect of foam volume and fly ash content on dry density is investigated intensively in order to find the relationship between each parameter and their abilities to counteract with each other. According to the above information, though there are quite a number of studies on the effect micro fiber on foam concrete at low volume fractions, there is still lack of information especially on the high fiber content side. The objective of the second study is to investigate further on the use of micro fiber at higher volume fraction and fill in the lacking information. Beside from this study, the investigation of the effect of micro-fiber (polypropylene) to enhance the properties of foam concrete is also carried out. Result: Of the two variables that are investigated in this study, the foam volume and the fly ash content, show significant effect on the properties of foam concrete. The foam volume tends to decrease the density and strength of foam concrete. In the second part of our study, a large fibre volume fraction is proved to be able to evidently increase the flexural strength of foam concrete up to about 40% due to the effect of fibre bridging over the crack and a significant number of fibres that intercepts the crack surfaces. However, the compressive strength is found to decrease severely due to the occurrence of large pores as the result of fibre being added into concrete mixture.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.4
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• pp.407-412
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• 2010

The objective of this study is the estimation of the mechanical properties of HIP-treated MMCs by an optimized manufacturing process. The Ti-MMCs were fabricated by HIP and rotary swaging (RS) for secondary processing. The Ti-MMCs with different tungsten fiber contents of 0, 6, 9, and 12 vol% were subjected to tensile tests, fatigue tests, and hardness tests. The results show that the hardness values of Ti-MMCs increased with the increasing volume percent of tungsten fibers, the tensile strength increased by approximately 50% (specific strength: 38%) at the 9 vol%. The value of tungsten-fiber orientation F affects the tensile strength. The fatigue strengths of the Ti-MMCs did not improve. HIP is a useful manufacturing method for Ti-MMCs and RS is an important process for improving fiber orientation during secondary processing.

• Korean Journal of Agricultural Science
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• v.48 no.2
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• pp.209-218
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• 2021

This study was carried out to investigate the effects of Bifidobacteria growth promoter BE0623 and a dietary fiber supplement, which included Bifidobacterium lactis BB12, Lactobacillus acidophilus, Streptococcus thermophilus, and Bifidobacterium lactis. In fermented milk containing BE0623, the viable cell count of Bifidobacteria significantly increased by about 45 to 75 times compared to the control, and the titratable acidity increased, whereas the pH decreased. All fractions obtained by isolating BE0623 had Bifidobacteria growth effect. Acacia dietary fiber is a pale yellow powder. It has a viscosity of 60 to 100 cPs and a pH between 4.1 and 5.0. Its general components are less than 10% moisture, more than 90% dietary fiber, and less than 4% ash. The optimal addition ratio of Bifidobacteria growth promoting material was determined to be 0.05%. The general components of the manufactured fermented milk were carbohydrate 17.85%, protein 3.63%, fat 3.00%, and dietary fiber 2.95%. During storage of the fermented milk for 24 days, its titratable acidity, viscosity, and sugar content all met the criteria. In addition, the viable cell counts of Bifidobacteria and lactic acid bacteria in the fermented milk were 1.7 × 10⁸ CFU·mL^-1 and 1.5 × 10⁷ CFU·mL^-1, respectively, and Escherichia coli was negative. There was no significant difference between the control group and the treatment group in the sensory evaluation of sweet, sour, weight, and flavor, and the preference for the treatment group was excellent. The acceptability of the fermented milk of the treated group according to the storage period was excellent in terms of color, flavor, and appearance.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2001.11a
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• pp.168-182
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• 2001

A new concept of stock preparation for the increase of bending stiffness in paper and board was proposed. The 'stiff' fibers, which were mechanically not treated or treated slightly to remove fiber curls, were combined with extensively refined fibers (ERF) to produce higher stiffness papers than those where the whole fibers were refined. The combination of 'stiff' fibers and extensively refined fibers produced higher stiffness at the same tensile strength than the control furnish, in which all the fibers are refined together. In this concept, the fibers from recycled papers could be as much useful as the virgin fibers as long as they are stiff enough or they can produce highly bondable fiber fractions by extensive refining. Use of the concept in real paper mill needs considerations such as increase of refining energy, slower drainage, and added drying burden, but savings of wood fibers, utilization of more recycled fibers, and increase of physical properties may offset the negative concerns. The success of this concept implementation in mills, therefore, depends on the wood fiber market around the mills and the proper decision making for the papermakers about how to apply this concept.

• New & Renewable Energy
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• v.2 no.2 s.6
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• pp.75-80
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• 2006

The effective thermal conductivities of $Mm(La_{0.6-0.8})Ni_{4.0}Co_{0.6}Mn_{0.2}Al_{0.2}$ [TL-492] with hydrogen and helium have been examined. Experiment results show that pressure has great influence on effective thermal conductivity in low pressure range [below 0.5 MPa]. And that influence decreases rapidly with increase of gas pressure. The reason is at low pressure, the mean free path of gas becomes greater than effective thickness of gas film which is important to the heat transfer mechanism in this research. And, carbon fibers have been used to try to enhance the poor thermal conductivity of TL-492. Three types of carbon fibers and three mass fractions have been examined and compared. Naturally, the highest effective thermal conductivity has been reached with carbon fiber which has highest thermal conductivity, and highest mass fraction. This method has acquired 4.33 times higher thermal conductivity than pure metal hydrides with quite low quantity of additives, only 0.99 wt% of carbon fiber. This is a good result comparing to other method which can reach higher effective thermal conductivity but needs much higher mass fraction of additives too.

• Advances in concrete construction
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• v.6 no.1
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• pp.29-45
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• 2018

This paper investigates the effect of inclusion of glass fibers on mechanical and fracture properties of binary blend geopolymer concrete produced by using fly ash and ground granulated blast furnace slag. To study the effect of glass fibers, the mix design parameters like binder content, alkaline solution/binder ratio, sodium hydroxide concentration and aggregate grading were kept constant. Four different volume fractions (0.1%, 0.2%, 0.3% and 0.4%) and two different lengths (6 mm, 13 mm) of glass fibers were considered in the present study. Three different notch-depth ratios (0.1, 0.2, and 0.3) were considered for determining the fracture properties. The test results indicated that the addition of glass fibers improved the flexural strength, split tensile strength, fracture energy, critical stress intensity factor and critical crack mouth opening displacement of geopolymer concrete. 13 mm fibers are found to be more effective than 6 mm fibers and the optimum dosage of glass fibers was found to be 0.3% (by volume of concrete). The study shows the enormous potential of glass fiber reinforced geopolymer concrete in structural applications.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.2
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• pp.207-212
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• 2004

Ruminal digestion of dry matter (DM) and neutral detergent fiber (NDF) of processed (ensiled, deepstacked or composted) broiler litter (BL) was determined in situ and in vitro, and compared with rice straw (RS). DM disappearances at 24 and 48 h and digestion of differently processed BL were higher than those of RS. Compared with RS, processed BL was low in NDF disappearance at 72 h incubation, digestion rate ($K_dB$) and digestibility at 0.025 of passage rate; however, deepstacked BL was similar in these NDF characteristics. Processing of BL affected ruminal digestion of nutrients such as DM and NDF adversely. NDF of composted BL, especially, was the most indigestible. This in situ nutritional evaluation indicated that deepstacked BL, the most widely used form of BL, was superior in DM characteristics (fractions, ruminal disappearance and digestibility) and similar in NDF characteristics (ruminal disappearance and digestibility) to RS.