• Transactions of Materials Processing
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• v.17 no.6
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• pp.436-442
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• 2008

As the structure of a mobile phone becomes thin to catch up with a slim product trend, the structural strength and resistance to shock of TFT-LCD module are getting to be reduced. Hence, TFT-LCD module is the strength reinforced by bezel frame. The bezel frame was produced by the multi hemming processes with several folding parts. The determination of the optimal number of hemming part and structure of bezel frame are very important process parameter to obtain the strength of that. The effect of process parameters on strength of bezel frame was investigated by FEA. Based on the result of FEA, the experiment was performed using manufactured hemming die, the result of the experiment was compared with FEA and verified. Also, three point bending tests were performed to check the strength of bezel frame.

• Steel and Composite Structures
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• v.19 no.2
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• pp.327-348
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• 2015

A numerical procedure is presented that provides ultimate curvature and moment domains for composite rectangular and circular cross-sections of reinforced concrete columns with or without an embedded steel section subjected to combined axial loading and biaxial bending. The stress resultants for the concrete and reinforcement bars are calculated using fiber analysis and the stress resultants for the encased structural steel are evaluated using an exact integration of the stress-strain curve over the area of the steel section. A dimensionless formula is proposed that can be used for any section with similar normalized geometric and mechanical parameters. The contribution of each material to the bearing capacity of a section (resistance load and moments) is calculated separately so that the influence of each geometric or mechanical parameter on the bearing capacity can be investigated separately.

• Steel and Composite Structures
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• v.10 no.2
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• pp.109-128
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• 2010

The expediency of using tubular composite steel and concrete columns of annular cross-sections in construction is discussed. The new type space framework with tubular composite columns of multi-storey buildings and its rigid beam-column joints are demonstrated. The features of interaction between the circular steel tube and spun concrete stress-strain states during the concentrical and eccentrical loading of tubular composite members are considered. The modeling of the bearing capacity of beam-columns of composite annular cross-sections is based on the concepts of bending with a concentrical force and compression with a bending moment. The comparison of modeling results for the composite cross-sections of beam-columns is analysed. The expediency of using these concepts for the limit state verification of beam-columns in the methods of the partial safety factors design (PSFD) legitimated in Europe and the load and resistance factors design (LRFD) used in other countries is presented and illustrated by a numerical example.

• Advances in nano research
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• v.14 no.3
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• pp.235-246
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• 2023

Nanotechnology, like any other revolutionary innovation in materials science, has significantly influenced the level of competition in sports. Nanotechnology provides various benefits and enormous potential to enhance athletic equipment, making players safer, more comfortable, and more agile. Various sporting equipment is being infused with nanomaterials, including carbon nanotubes (CNTs), silica nanoparticles (SNPs), nanoclays fullerenes, etc., to enhance athlete and equipment performance. Each of these nanomaterials gives athletic equipment an extra benefit like high strength and stiffness, longevity, decreased weight, abrasion resistance, etc. This paper mechanically analysis the structural strength of tennis equipment to avoid injury. As a result, the bending forces are applied to the reinforced structures to investigate their durability.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.23-24
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• 2023

In this study, an easily recyclable separable glued-laminated timber (GLT)-steel beam was developed, and a structural design method was presented. The GLT and steel were mechanically composited using self-tapping screws. The GLT-steel beam was designed to fail in the compression of GLT. The bending moment and load-carrying capacity of the GLT-steel beam were predicted based on composite beam theory and compared with experimental test data. As a result, the GLT-steel beam exhibited ductile behavior, and compression failure of GLT was observed. The screw connection showed no damage while the steel plate was extended. The load-carrying capacity of GLT after failure was similar to the load resistance predicted by the compressive strength of GLT and the tensile strength of steel. This indicates that the ductile behavior of the GLT-steel beam can be safely designed by the tensile strength (yield) of steel.

• Computers and Concrete
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• v.34 no.1
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• pp.49-61
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• 2024

The present study concerns a removal of chloride ions and structural behaviour of concrete beam at electrochemical chloride extraction (ECE). The electrochemical properties included 1000 mA/m2 current density for 2, 4 and 8 weeks. It was found that an increase in the duration of ECE resulted in an increase in the extraction rate of chlorides, in the range of 35-85%, irrespective of chloride contamination. In structural behaviour, the strength and maximum bending moment of specimen was always lowered by ECE. Moreover, the flexural rigidity and bending stiffness were reduced by the loss of effective cross-section area in the linear elastic range. Simultaneously, the inertia moment was substantially subjected to 70% loss of the cross-section by the tensile strain at the condition of the failure. However, a lower rate of the inertia moment reduction was achieved by ECE, implying the higher resistance to the cracking, but the higher risk of deformation.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.3
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• pp.314-320
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• 2022

The function of reinforcing fibers used in building materials is to maintain resistance to bending loads and to function for cracking caused by drying shrinkage. High-density fiber-cement composites are mainly used for linear plates and are used to increase bending resistance. Therefore, tensile properties, bonding strength with cement hydrate, alkali resistance, and the like are required. Recently, as the non-combustible performance has been strengthened, a function to minimize the occurrence of sparks during high-temperature heating has been added. Therefore, the use of organic fibers is limited. In this study, a study was conducted to replace polypropylene used as reinforcing fiber with hemp fiber with excellent heat resistance. Hemp fibers have excellent heat resistance, good affinity with cement, and excellent alkali resistance. Based on the total volume of polypropylene fibers used in the existing formulation, the non-combustible performance was compared and evaluated by using hemp fibers instead of the polypropylene fibers, and basic physical properties such as flexural strength were tested. As a result of conducting a non-combustibility and physical property test using hemp fibers with a fiber length of 7 mm using 2 % and 3 % by weight, it was found that there is no remaining time of the flame, and the flexural strength can be secured at 95 % level of the existing polypropylene fiber.

• Journal of Ocean Engineering and Technology
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• v.22 no.5
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• pp.83-86
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• 2008

This paper deals with the experimental works for the correlations of ice resistance for icebreaker with synthetic(model) ice in general towing tank and with refrigerated ice in ice tank. In order to find out the correlation, the density variation is mainly focused in the present study. The model of Terry-Fox ice breaker has been used for the present correlation study because many data are available to be compared. According to the increase of density, the correlation becomes better quantitatively as well as qualitatively. Other parametric studies such as an ice size, a friction coefficient, a bending moment, etc., are also expected to be carried out to have better correlation in a near future. This research could be the basis for the possibility of resistance test using a synthetic ice in a general towing tank instead of an expensive ice tank.

• Journal of the Korea Furniture Society
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• v.21 no.4
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• pp.284-292
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• 2010

This research was carried out to examine the properties of fancy cherry veneer overlaid on the PF resin bonded Meranti plywood floor, which 2.5% green tea leaf powder was applied in the UV varnishes and the adhesives for scavenging the volatile organic compounds. The results were as follows: 1. The various properties of the treated samples, such as density, moisture content, thickness swelling, bending strength(MOR), adhesion shear strength, surface abrasion, curling, cyclic delamination test with boiling water, boiling property, cold-resistance and heat resistance, acid resistance and alkali resistance, and anti-contamination property showed no significant difference between the properties of the control samples. 2.5% green tea leaf powder treated floor gave a little better results than the control for surface scratch test. 2. In case of QUV and weathering test, no difference between the treated sample and control was found. 3. The floor was discolored by adding 10% green tea leaf powder to UV coating, and the floor was also discolored to light green during by the soaking test. The color of floor was not changed up to 5% addition level.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.1
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• pp.149-159
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• 2009

The purposes of this study are to evaluate physical performance of metallic Jacquard fabrics, and to contribute to the research and development of the women's suit made of the metallic Jacquard fabrics. First, eight fabrics were woven with two kinds of warp yarns(nylon and rayon) and weft yarn blended with various contents(0, 7, 14, 21%) of metallic yarn. Second, the mechanical properties were measured by using the KES-FB system, and physical properties such as tensile strength, tearing strength, abrasion resistance, drape, pilling, snagging, degree of crease resistance, flexural stiffness, specular gloss, folding endurance and electrostatic propensity were measured. The results were as follows. As the metal fiber content increased, bending, shear, thickness and weight increased, which imply low recovery of wrinkles. It means that metallic Jacquard fabrics enable to use as a memory fabric. 7% metallic Jacquard fabric showed a low value at total hand value, but there was little change. As the metal fiber content increased, tensile strength, tearing strength, drape coefficient, specular gloss and flexural stiffness increased, however the degree of crease resistance, electrostatic propensity and folding endurance decreased. The metallic Jacquard fabrics were excellent in snagging, abrasion resistance and pilling.