• Structural Engineering and Mechanics
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• v.87 no.4
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• pp.333-346
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• 2023

This paper presents findings from an experimental study that was focused on evaluating the use of Forta-Ferro (FF) and Polyvinyl Alcohol (PVA) fibers on the response of moderate and special ductility beams under load cycles. For this reason, eight full-scale specimens, identical in geometry, were subjected to gradual cyclic loading. The specimens included two plain concrete beams with medium and special ductility, three beams with medium ductility and stirrup spacing of one-quarter the effective depth (d/4) and three beams with special ductility, and stirrup spacing of one-half the effective depth (d/2), strengthened with FF and PVA fibers separately. The use of fibers was aimed at reducing the amount of shear reinforcement in flexural members. Here, the variation of parameters including the maximum strength, ultimate strength, stiffness, ductility, damage index, energy dissipation, and equivalent damping was studied. Utilizing FF and PVA fibers improved the performance in beams with moderate ductility when compared to those beams with special ductility. Therefore, in special ductility beams, fibers can be used instead of crossties and in moderate ductility beams, fibers can be added to reduce the ratio of shear reinforcement. Furthermore, increasing the stirrup spacing in the moderate ductility beams from d/4 to d/2 and adding 0.6% FF or 1.5% PVA fibers resulted in behavior similar to those of the moderate ductility beam.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.1
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• pp.15-22
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• 2008

For the improvement of letterpress printing paper quality, special fibers obtained from the sea were used by mixing with wood fibers. The sizes of the special fibers, which were from red algae in the sea, were 0.5-1 mm in length, and 3-7 ${\mu}m$ in width, respectively, and the fibers were supplied by Pegasus Research Inc. for the study. From the study, it was found that 10% addition of algae fibers greatly improved paper surface strength and internal bonding strength. The compressibility was estimated by utilizing 'Print-surf method' at high clamping pressure and with hard backing. Again, 10% addition of algae fibers greatly improved the compressibility of the paper. These results were expected that algae and wood fibers were distributed evenly through the sheet, and integrated one another to leave no empty space inside the paper.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.3
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• pp.1-8
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• 2001

Paper consists of fiber network and paper properties were highly affected by fiber characteristics. Many researchers have tried to relate fiber and paper properties. Softwood and hardwood fiber's are quite different in their properties. Generally, softwood fiber's are longer and more flexible than hardwood fibers. At present, many paper mills make mixed paper with softwood and hardwood fibers except for special grade. During fracture some fiber's are broken and others are pulled out. In this paper, the number of broken and pulled out fiber's during fracture is analyzed depending on the mixing ratio of softwood and hardwood fiber's. Fiber length, curl, kink, coarseness, WRV and formation index were measured. Double-edged strength samples were prepared to observe the number of broken and pulled out fiber's. Mixed paper strength was decreased with increasing hardwood fibers ratio. During fracture, softwood fiber's were more likely broken and hardwood fibers were more likely pulled out. The strength of paper which consists of softwood fibers was determined by fiber's broken strength and that of hardwood fibers by fiber's debonding strength. Paper strength was changed depending on the fiber's bonding capability. If the fiber is longer and more flexible, the fiber network becomes stronger and stiffer.

• Nutrition Research and Practice
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• v.6 no.1
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• pp.28-34
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• 2012

The objective of this study was to estimate the contents of dietary insoluble and soluble fiber in school meal. Samples of the school meals were collected from May to June in 2008. Three elementary schools and three middle schools around Masan area were selected for analysis. Dietary soluble and insoluble fibers in the school meals were analyzed directly by the AOAC method. From the initial experiment phase, we used cellulose and pectin as a standard of dietary fiber, and average recovery rate of insoluble fiber and soluble fiber was calculated. The recovery rate was observed, the cellulose $109.7{\pm}11.7%$ (range 90~150%) and pectin $77.8{\pm}10.8%$ (range 64.7~96.7%), respectively. The amounts of insoluble fiber and soluble fiber were analyzed in the total of 66 dishes, which included 7 kinds of cooked rice (bab) made with some cereal products and vegetables, 19 kinds of soup (guk) made with meats or vegetables, 11 kinds of kimchi, 21 kinds of entr$\acute{e}$es or side dishes, and 8 special dishes. Conclusively the school meal, per serving size, would provide above 75% KDRI of total dietary fibers through mainly soups and special menu, with the exception to fruits. In addition, it might be expected that children could consume more soluble fiber from the meals with the special dishes than from the regular ones.

• CELLMED
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• v.9 no.3
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• pp.2.1-2.7
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• 2019

Sesame (Sesamum indicum L.) is a rich source of edible oil most commonly it is used as a food product mainly in bakeries and also use as a common source of oil in daily kitchen needs. Due to the presence of some special phytochemicals like proteins, fibers, oil, minerals and antioxidants it is highly used for medicinal and therapeutic purposes. It is a good source of energy and act as an antiaging agent. Its seeds are used as Anti-helmintic, antihypertensive, antimicrobial, cytotoxic and Hepatoprotective but its seed coat which is a byproduct of sesame and a cherished source of fibers is normally use for animal feedstuff. In Unani system of medicine it is used both as drug & diet (dawa wa ghida). In classical Unani literature it is indicated in various disorders like Asthma, Dry Cough, Gastritis (due to any drug, excessive use of alcohol), Dryness of Intestine, Dryness in throat, Renal Stone, Bleeding Piles, Amenorrhea, Retention of urine, Dysuria, Orchitis, Sexual Debility, Anorexia. The present review article, an attempt have been made to compile all the pharmacological and Pharmacognostical characters of Sesamum indicum with special reference to Unani literature.

• Computers and Concrete
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• v.26 no.4
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• pp.367-375
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• 2020

Today, the use of special technologies in the admixture of concrete has made tremendous progress, but the problem that has always existed in the construction of concrete members is the brittleness and lack of loading bearing after cracking, which leads to reduced strength and energy absorption. One of the best ways to fix this is to reinforce the concrete with steel fibers. Steel fibers also control cracks due to dry shrinkage, reduce structural crack width, and improve impact resistance. In this study, recycled steel fibers from worn tires have been used in the manufacture of concrete samples, the secondary benefits of which are the reduction of environmental pollution. One of the disadvantages of steel fiber reinforced concrete is the corrosion of steel fibers and their deterioration in harsh environments such as coastal areas. Corrosion caused by chlorine ions in metal fibers causes deterioration and early decommissioning of structures in corrosive environments. In this study, the effect of the dosage of steel fibers (dosages of 15, 30, and 45 kg of fibers per cubic meter of concrete) and aspect ratio of fibers (aspect ratio of 25 and 50) on compressive and flexural strength of concrete samples are investigated. In the following, the effect of fiber corrosion on the results of the mechanical properties of concrete samples is examined. The results show that the increase in fiber causes a relative increase in compressive strength, and a significant increase in flexural strength, and corrosion of steel fibers without reducing workability reduces compressive strength and flexural strength by up to 6 to 11%, respectively.

• Composites Research
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• v.23 no.3
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• pp.50-57
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• 2010

It is important to detect fibers in the sectional image of fiber reinforced cementitious composites (FRCC), since the fiber distribution is a crucial factor to predict or evaluate the mechanical performance of FRCC. In this paper, we investigated the fluorescence characteristics of Polyvinyl Alcohol (PVA) fibers, Polyethylene Terephthalate (PET) fibers, Polyethylene (PE) fibers, and Polypropylene (PP) fibers used in Engineered Cementitious Composites (ECC), which is a special kind of FRCC that incorporates synthetic fibers and exhibits extremely ductile behavior in uniaxial tension, to detect each fiber according to its type. Furthermore, optimum excitation and emission wavelengths were proposed on the basis of maximum difference of Relative Fluorescence Intensity (RFI) between two types of fibers used in the hybrid ECC. Optimum threshold values to discriminate two types of fibers using statistical tools were also proposed. Finally, images of four types of fibers obtained using a fluorescence microscope are compared.

• Korean Journal of Materials Research
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• v.19 no.10
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• pp.562-568
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• 2009

Electrospinning is a technique that produces sub-micron sized continuous fibers by electric force from polymer solutions or melts. Due to its versatile manufacturability and the cost effectiveness, this method has been recently adopted for the fabrication of one-dimensional materials. Here, we fabricated polyacrylonitrile (PAN) polymer fibers, from which uniform carbon fibers with diameters of 100-200 nm were obtained after carbonization at 800 $^{\circ}C$ in N$_2$. Special emphasis was directed to the influence of the phase separated polymer solution on the morphology and the microstructure of the resulting carbon fiber. The addition of poly(stylene-co-acrylonitile) (SAN) makes the polymer solution phase separated, which allows for the formation of internal pores by its selective elimination after electrospinning. XPS and Raman Spectroscopy were used to confirm the surface composition and the degree of carbonization. At the PAN:SAN = 50:50 in vol%, the uniform carbon fibers with diameters of 300$\sim$500 nm and surface area of 131.6 m$^2$g$^{-1}$ were obtained.

• Composites Research
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• v.22 no.4
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• pp.41-49
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• 2009

Natural fiber reinforced composites are emerging as low-cost, lightweight, recyclable, and eco-friendly materials. These are biodegradable and non-abrasive. Due to eco-friendly and biodegradable characteristics of natural fibers, they are being considered as potential candidates to replace the conventional fibers. The chemical, mechanical, and physical properties of natural fibers have distinct features depending upon the cellulose content of the fibers which varies from fiber to fiber. The mechanical properties of composites are influenced mainly by the adhesion between matrix and fibers. Several chemical and physical modification methods of fiber surface were incorporated to improve the tiber-matrix adhesion resulting in the enhancement of mechanical properties of the composites. This paper outlines the works reported on natural tiber reinforced composites with special reference to the type of fibers, polymer matrix, processing techniques, treatment of fibers, and fiber-matrix interface.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.209-209
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• 2006

Ultra-fine fibers are spun by expensive fiber spinning technology using special spinnerets. Ultra-fine fibrous materials have attracted considerable attentions because of their potential applications as high performance wiping cloths, water absorbent sound proofing materials and moisture transfer sporting good. However, production expense of ultra-fine fibers is 5 to 7 times higher than general textile materials. The objective of this research is to develop cost-effective recycling process to produce multi-functional ultra-fine fibrous material in terms of the development of garnetting and carding machines for ultra-fine fibrous material waste and scrap. The efficiency of sound absorption for the recycled polyester nonwoven increased with decreasing length and thickness of component fibers, which was attributed to the reduction of air permeability. It is expected that high value and cost-effective textile products are developed using ultra-fine fibrous wastes and that sound proofing material and oil absorbent f