• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.11a
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• pp.535-536
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• 2018

• Journal of the Korean GEO-environmental Society
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• v.19 no.4
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• pp.17-26
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• 2018

This study systematically examines the changes in the compressive and tensile strength of soil cement reinforced by natural hair fiber, which is regularly produced from human. Extensive experimental tests of various test specimens have been carried out in a laboratory. Several factors are considered, including the soil type, amount of cement, amount of fiber, fiber length, loading type, and curing age. The test results indicate that both the compressive and tensile strengths are significantly affected by the fiber, either increasing or decreasing depending on the conditions. The increase in tensile strength is significant in the sand-based soil cement due to the tensile resistance of the fiber which is interlocked with the surrounding soil or cement particles. The natural fiber provides a larger strain to failure due to its extensibility, which allows greater deformation. Based on the test results, natural hair fibers can be an effective and environmentally friendly way to improve soil ground subjected to tensile loading, such as an embankment slope, road subgrade, or landfill, thus reducing the cost for cement and waste treatment. The study results provide a useful information of better understanding the mechanical behavior of natural hair fiber in soil cement and the practical use of waste materials in civil engineering. The findings can be practically applied for improving earth structures under tensile loading.

• Advances in concrete construction
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• v.13 no.6
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• pp.433-450
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• 2022

The conventional disposal methods of waste tires are harmful to the environment. Moreover, the recycling/reuse of waste tires in domestic and industrial applications is limited due to parent product's quality control and environmental concerns. Additionally, the recycling industry often prefers powdered rubber particles (<0.60 mm). However, the processing of waste tires yields both powdered and coarser (>0.60 mm) size fractions. Reprocessing of coarser rubber requires higher energy increasing the product cost. Therefore, the waste tire rubber (WTR) less favored by the recycling industry is encouraged for use in construction products as one of the environment-friendly disposal methods. In this study, WTR fiber >0.60 mm size fraction is collected from the industry and sorted into 0.60-1.18, 1.18-2.36-, and 2.36-4.75-mm sizes. The effects of different fiber size fractions are studied by incorporating it as fine aggregates at 10%, 20%, and 30% in the self-compacting rubberized concrete (SCRC). The experimental investigations are carried out by performing fresh and hardened state tests. As the fresh state tests, the slump-flow, T500, V-funnel, and L-box are performed. As the hardened state tests, the scanning electron microscope, compressive strength, flexural strength and split tensile strength tests are conducted. Also, the water absorption, porosity, and ultrasonic pulse velocity tests are performed to measure durability. Furthermore, SCRC's energy absorption capacity is evaluated using the falling weight impact test. The statistical significance of content and size fraction of WTR fiber on SCRC is evaluated using the analysis of variance (ANOVA). As the general conclusion, implementation of various size fraction WTR fiber as fine aggregate showed potential for producing concrete for construction applications. Thus, use of WTR fiber in concrete is suggested for safe, and feasible waste tire disposal.

• Journal of Sericultural and Entomological Science
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• v.42 no.2
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• pp.109-113
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• 2000

The preparation of skin care gauze could be make to mixing separated cellulose from waste milk pack and degummed silk fibroin fiber. Also, its wound covering and anti-bacterial activity were investigated in order to find out the enhancement of their functionality. By the 30% silk fibroin fiber including skin care gauze, the anti-bacterial activity values of Staphylococcus strain are much 4 times higher than of 0∼10% silk fibroin fiber including skin care gauze. The average yield of cellulose from waste milk pack was obtained 50-60%, and their morphologies, physical properties, modulus and biodegradation ratios are studies, respectively.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.45-46
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• 2022

Recently, it is necessary to establish an eco-friendly construction system through recycling of waste material management at construction sites. This is required to reflect the times that require a carbon reduction system in construction as part of domestic and overseas carbon dioxide reduction. Therefore, we intend to establish eco-friendly construction management as part of resource recycling and carbon reduction through recycling technology for waste fibers generated at construction sites.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.903-908
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• 2002

The production of waste glasses has been increased with the development of industry. The utilization of waste glass for concrete can cause the concrete to be cracked and to be weakened due to an expansion by alkali-silica reaction(ASR). When used the fibers with waste glass, there is an effect on reduction of expansion and strength loss due to ASR between the alkali in the cement paste and the silica in the waste glass. In this study, we conducted basic experimental research to analyze the possibilities of recycling of amber waste glass as fine aggregates for steel fiber reinforced concrete. Test results of fresh concrete. slump is decreased because grain shape is angular and air content is increased due to involving small size particles so much in waste glasses. Also. tensile and flexural strengths increased as the content of steel fibers increased. In conclusion, the content of waste glass below 40% is reasonable and usage of pertinent admixture is necessary to obtain workability or air content.

• Steel and Composite Structures
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• v.45 no.1
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• pp.147-157
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• 2022

This study assessed the compressive and tensile strengths and modulus of elasticity of waste polyethylene terephthalate (PET) using the ASTM standard tests. In addition, short carbon and glass fibers were mixed with waste PET to examine the improvements in ductility and strength during compression. The bonding was examined via field-emission scanning electron microscopy. The strength degradation of the waste PET tested under UV was 40-50%. However, it had a compressive strength of 32.37 MPa (equivalent to that of concrete), tensile strength of 31.83 MPa (approximately ten times that of concrete), and a unit weight of 12-13 kN/m3 (approximately half that of concrete). A finite element analysis showed that, compared with concrete, a waste PET pile foundation can support approximately 1.3 times greater loads. Mixing reinforcing fibers with waste PET further mitigated this, thereby extending ductility. Waste PET holds excellent potential for use in foundation piles, especially while mitigating brittleness using short reinforcing fibers and avoiding UV degradation.

• Journal of the Korean Ceramic Society
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• v.56 no.6
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• pp.577-582
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• 2019

Recently, E-glass fiber is the one of most widely used ceramic fiber for aerospace fields. Recycling technology for waste of wind power blades is arising issue for reasons of low manageability and high cost of wastes. Though glass fiber is perfectly dissolved in hydrofluoric acid, low cost for recycling and harmless to human is important for recycling of blades. Chemically melted glass fiber will be used as different purpose like accelerator of hardening for shotcrete. In this study, dissolution process of glass fiber is tested in NaOH solution at low temperatures. In addition, difference in diameter reduction of glass fiber is observed by various alkali concentration and reaction times, treatment temperatures using FE-SEM.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.3
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• pp.169-176
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• 2000

This experiment was carried out to investigate the effects of application levels of food waste compost andmineral nitrogen in 3 cuttings per annurn on the nutritive value and nutrient yields of orchardgrass (Dactylisglomerata L.). Annual food waste compost (FWC) and mineral nitrogen were applied at levels of 0, 10, 20,40 and 60 ton ha-', and 0, 90, 180 and 270 kg ha-', respectively. The contents of crude protein (CP, %) oforchardgrass were significantly higher at the application levels of 40 ton ha-' yr-' by FWC than those atapplication levels of 0 ton ha-' yr-' (p<0.05), the contents of neutral detergent fiber (NDF, %), acid detergentfiber (ADF, %) and hemicellulose were also higher in FWC applied plots, except for the FWC levels of 10and 60 ton ha-' yr-'. The contents of total digestible nutrient (TDN, %) and relative feed value (RFV) oforchardgrass were significantly higher at FWC levels of 10 and 60 ton ha-' yr-' than at levels of 0 ton ha"yr-'. Annual yields of CP and TDN were increased with increase the FWC levels. The highest contents ofCP of orchardgrass were obtained at 1st cut, NDF and ADF at 2nd cut. As the mineral nitrogen fertilizationwas increased, the contents of CP, NDF, ADF and hemicellulose of orchardgrass were significantly increased,but TDN and RFV were decreased. .Annual yields of CP and TDN of orchardgrass were significantlyincreased with increase the mineral nitrogen fertilization.(Key words : Food waste compost, Mineral nitrogen, Crude protein, Neutral detergent fiber, Acid detergentfiber)rgent fiber, Acid detergent fiber)

• Journal of the Korean Graphic Arts Communication Society
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• v.18 no.1
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• pp.121-139
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• 2000

This study is to test the possibility of applying the low-molecular weighted waste cellulase, which is produced in the process of cellulase production, to paper making. After experimenting on high-crystallized non-wood fibers with beating catalyst. I got the result that the condition for the optimal effect is temperature 40~6$0^{\circ}C$, the time 90min to 120min, pH 5.0 to 6.0, the enzyme contents 0.3% and that the effect of beating such as slight reduction of fiver viscosity, increase of water retention value(WRV) and shortening of fiber length was increased with waste cellulase. Through this process, the density, folding endurance, tensile strength and burst strength of paper was remarkably increased, which is inferred to result from the increased flexibility of fiber by individual characteristics of non-wood fiber, which was high-crystallized by penetrated low-molecular weight cellulases in the fiber.