• Restorative Dentistry and Endodontics
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• v.44 no.4
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• pp.37.1-37.10
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• 2019

Objectives: This study evaluated the bond strength of various fiberglass post cementation techniques using different resin-based composites. Materials and Methods: The roots from a total of 100 bovine incisors were randomly assigned to 5 treatment groups: G1, post + Scotchbond Multi-Purpose (SBMP) + RelyX ARC luting agent; G2, relined post (Filtek Z250) + SBMP + RelyX ARC; G3, individualized post (Filtek Z250) + SBMP; G4, individualized post (Filtek Bulk-Fill) + SBMP; G5, individualized post (Filtek Bulk-Fill Flow) + SBMP. The samples were subjected to the push-out (n = 10) and pull-out (n = 10) bond strength tests. Data from the push-out bond strength test were analyzed using 2-way analysis of variance (ANOVA) with the Bonferroni post hoc test, and data from the pull-out bond strength test were analyzed using 1-way ANOVA. Results: The data for push-out bond strength presented higher values for G2 and G5, mainly in the cervical and middle thirds, and the data from the apical third showed a lower mean push-out bond strength in all groups. No significant difference was noted for pull-out bond strength among all groups. The most frequent failure modes observed were adhesive failure between dentine and resin and mixed failure. Conclusions: Fiberglass post cementation using restorative and flowable bulk-fill composites with the individualization technique may be a promising alternative to existing methods of post cementation.

• Journal of Korea Soil Environment Society
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• v.4 no.1
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• pp.69-73
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• 1999

The study was performed to examine the elimination capacity of impurity on the fiberglass wicks to exert a suction of Passive capillary samplers (PCAPS) on soil water. This impurity affects the capillary properties of the wick and the chemical properties of the samples collected. To determine the need, capillary rise and moisture contents were measured after the wicks were cleaned by four methods : combustion, acetone extraction, detergent washing, and uncleaning. The wicks were made with fibers produced by PPG Industries and Manville Company, U.S.A. Results showed that wicks made from PPG fibers lost up to 3.4% of original mass during combustion while Manville fiber wicks lost only up to 0.6%. These losses are assumed to have been due to combustion of organic compounds applied by the manufacturers. All cleaning methods had higher capillary rise than obtained with uncleaning method Combustion at 40$0^{\circ}C$ for 4 hours was the best cleaning method. removing 98 to 100% of impurities.

• Journal of Veterinary Clinics
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• v.39 no.4
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• pp.185-191
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• 2022

An Amur softshell turtle with multiple shell injuries was admitted to the Seoul Wildlife Center on 19 May 2021. The most severe lesion was a puncture wound requiring urgent closure. In addition to routine supportive therapy, the damaged shell was patched with biocompatible polymethyl methacrylate (PMMA) materials (bone cement and dental acrylic) and fiberglass. Despite a few methods to repair the carapace or plastron of hard-shelled turtles, shell repair in the Amur softshell turtle has rarely been reported. This paper reports the repair process of a puncture wound in the carapace of a softshell turtle using polymethyl methacrylate (PMMA). PMMA is a biocompatible acrylic polymer that forms a tight structure that holds the implant against tissue defects, such as skin, bones, and dentures. Fiberglass, a preferred fiber in various medical fields, was used with PMMA to provide extra strength and waterproof capability. After the procedure, there were no signs of edema, inflammation, bleeding, skin discoloration, or any other complications. Accordingly, this can be a method of choice in softshell turtles using biocompatible materials to cover the lesion in the carapace and provide appropriate wound management, supportive therapy, and a suitable course of antibiotics considering all other circumstances.

• Journal of Korea Ship Safrty Technology Authority
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• v.15
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• pp.45-53
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• 2004

세계적으로 레저선박에서 가장 일반적인 선체의 재질은 아직까지 Fiberglass Reinforcement Plastic이다. 선체의 재질이 아직까지 FRP에서 알루미늄으로 변화하지 못하는 이유는 중, 소형 선박을 다량으로 제조할 때 FRP는 가장 효율적인 작업이 가능하고 경제성이 뛰어나며 선체의 외관에 제약이 크게 없는 재료이기 때문이다.<중략>

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.170-170
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• 2010

The energy conversion from the temperature difference between hot and cold source like ocean thermal energy conversion (OTEC), requires a long and large-diameter pipe (about 1000 to 10,000 meters long) to reach the deep water. The pipe diameter ranges from 2.8 meter for proposed early test systems, to 5 meter for large, commercial power generation systems. The pipe must be designed to resist collapsing pressures produced by water temperature and density differences, and the reduced pressure required to induce flow up the pipe. Other design considerations include the external-drag effect on the pipe due to ocean currents, and the wave-induced motions of the platform to which the pipe is attached. Various approaches to the pipe construction have been proposed, including aluminum, steel, concrete, and fiberglass. More recently, a flexible pipe construction involving the use of fiberglass reinforced plastic has been proposed. This report presents the results of a scaled fixed cold water pipe (CWP) model test program performed by EES(Engineering Equation Solver) to demonstrate the feasibility of this pipe approach.

• Structural Engineering and Mechanics
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• v.50 no.6
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• pp.817-834
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• 2014

An experimental program was designed in the current work to examine the structural behavior of ferrocement beams reinforced with composite materials under three point loadings up to failure. The experimental program comprised casting and testing of twelve ferrocement beams having the dimensions of 120 mm width, 200 mm depth and 1600 mm length. The twelve beams were different in the type of reinforcements; steel bars, traditional wire meshes (welded and expanded wire meshes) and composite materials (fiberglass wire meshes and polypropylene wire meshes). The flexural performances of the all tested beams in terms of strength, ductility, cracking behavior and energy absorption were investigated. Also all the tested beams were simulated using ANSYS program. The results of the experimental tests concluded that the beam with fiber glass meshes gives the lowest first crack load and ultimate load. The ferrocement beam reinforced with four layers of welded wire meshes has better structural behavior than those beams reinforced with other types of wire meshes. Also the beams reinforced with metal wire meshes give smaller cracks width in comparing with those reinforced with non-metal wire meshes. Also the Finite Element (FE) simulations gave good results comparing with the experimental results.

• Journal of Korean Tunnelling and Underground Space Association
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• v.3 no.1
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• pp.11-19
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• 2001

The purpose of this study is to improve the problems in Umbrella Arch Method, such as the oxidation, the difficulties in installation and cutting of the steel pipe. The applicability of the high strength FRP (Fiber-Reinforced-Plastic) materials composed of glass fiber as a substitute of steel pipe was investigated in this study. The results of this study show that FRP material is better than steel pipe in work performance and the durability of material except for its price. From the numerical analysis with various types of FRP, it was evaluated that the equiangular curve type is more efficient than the flat type developed abroad, and the supporting effect of FRP-grout mixture is similar to that of steel-grout mixture in results of bending strength test.

• Journal of Korean Society for Quality Management
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• v.48 no.2
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• pp.257-267
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• 2020

Purpose: The purpose of this study is to define guideline for fiber-glass-resin-putty repairing method for submarine GFRP by comparing structural strength between normal GFRP and putty repaired GFRP. Methods: GFRP specimen tensile and flexural tests are conducted in accordance with ASTM D3039/3039M-17 and ASTM D790 Procedure A. The collected data was analysed whether satisfies its structural strength criteria. Furthermore, It is analysed to find dominant reason of structural strength changes. Results: The result of the study is as follows; flexural strength of GFRP is satisfied strength criteria for all test cases, but tensile strength is not satisfied its criteria for some cases which over 2 mm depth of surface damage. Conclusion: The fiberglass-resin-putty repairing method should be applied to under 2 mm depth of damage which is not affecting to roving fiber layer destruction in GREP laminate.

• Journal of Korean Association for Spatial Structures
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• v.10 no.3
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• pp.41-48
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• 2010

The architectural membrane generally consists of weave and coating, and the PTFE membrane consists of fiberglass weave and polytetrafluoroethylene coating. The weave is usually made of fiberglass $\beta$-yarn. The $\alpha$-yarn, which is thicker than $\beta$-yarn, is also increasingly used for the weave. However, the characteristic data of the architectural membrane that is made of $\alpha$-yarn weave is still insufficient. Therefore, further studies are needed on the mechanical characteristics of the membrane according to the thickness of the yarn used for the weave that comprises the architectural membrane. This study was performed to identify the mechanical behaviors of the membranes with $\alpha$-yarn and $\beta$-yarn.

• Nuclear Engineering and Technology
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• v.53 no.12
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• pp.4003-4013
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• 2021

During the long-term cooling (LTC) phase of a loss-of-coolant accident (LOCA) in a pressurized water reactor (PWR), water is supplied from the containment sump to the reactor coolant system (RCS) by the flooded sump water to the Reactor Vessel (RV) through the broken pipes. As part of the technical efforts for resolving GSI-191 [( Reid and Crytzer, May. 2007) 1, consideration is needed for the consequences of debris penetrating the sump screen and propagating downstream into the RV. Injection of debris (fiberglass) into the RV during the LTC recirculation phase needs special attention to assure that reactor core cooling is maintained. The point of concern is the potential for debris to adversely affect the reactor core flow paths or heat transfer [2]. However, all the experiments for proving the coolability of RV have been done with the assumption of the most of debris would be transferred to the RV and the bottom nozzle of the FAs. The purpose of the tests is to quantify the amount of the debris that would be accumulated at the lower plenum and the debris that passes through the FAs since non-conservatism of other researches assumptions that have been used in the past experimental or analytical programs.