• Journal of Sensor Science and Technology
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• v.28 no.5
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• pp.318-322
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• 2019

In shooting training, an impact point identification system that uses the impact wave of the bullet to check the impact point in the target plate has been recently used. Acoustic sensors used in these systems must be able to detect shock waves of high sound pressure levels and be both waterproof and dustproof for rainy weather and dusty environments, respectively. In this study, membranes with excellent waterproof, dustproof, and sound transmitting characteristics were selected through a characteristics test; a protection cap was installed to install the selected materials. After coupling the produced protection cap to the acoustic sensor housing, the sensitivity and phase characteristics of the acoustic sensor were checked. Through the waterproof and dustproof test, the performances of its sensitivity and phase characteristics were confirmed. Finally, the normal shockwave of a 5.56 mm diameter bullet was measured using a shockwave detection signal collecting plate equipped with a prototype of the acoustic sensor at a 100 m firing range.

• Fashion & Textile Research Journal
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• v.17 no.5
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• pp.854-861
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• 2015

This study evaluates the objective and subjective hand as well as the preference for hand and outdoor jackets on laminated waterproof breathable fabrics with different constituent characteristics to identify those best suited for consumer needs. Mechanical properties and objective hands were measured by the KES-FB system. The subjective hand and the preference of laminated waterproof breathable fabric for outdoor jackets were rated by the 20's and 30's women experts with tactile and visual senses that utilized a questionnaire with a seven-point semantic differential scale; subsequently, the flexibility and compressive elasticity of laminated waterproof breathable fabrics were low. However, light and thin waterproof breathable fabrics with a smooth surface had high scores in smoothness, fullness & softness and total hand value. In addition, laminated waterproof breathable fabrics were classified into three hand factors: flexibility, density, and surface properties. There were significant differences on flexibility and surface property perceptions, hand and out-door jackets preferences according to the characteristics of waterproof breathable fabrics. The hand preference of the laminated waterproof breathable fabric improved with decreasing 2HB and increasing EM. However, EM showed positive effect for outdoor jacket preferences. Those that were flexible and smooth were preferred for outdoor jackets.

• Fibers and Polymers
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• v.4 no.2
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• pp.71-76
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• 2003

We evaluated the seam characteristics with finishing, seaming and sealing processes and seam Puckering behavior of the breathable waterproof fabrics with laser scan. There were differences in 99% significant level between the seamed fabric and the sealed fabric. Seam breakage was initiated with the breakage of sewing thread, so the seam strength after seaming was almost uniform. The sewn seam strength and elongation increased with sealing process in all finishing methods. Pucker grade of laminating type was generally much higher than that of the coating type. We confirmed that wave length and amplitude have more important meaning than the number of weave in the breathable waterproof fabrics. The puckering in breathable waterproof fabrics is mainly occurred by inherent and feeding pucker. The former if due to the insertion of sewing thread and the littler is caused by differential feeding when two pieces of fabric are fed into the gap between a press foot and needle plate.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.6
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• pp.583-591
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• 2012

This study selected three model designs used for air injection type welding clothes designed for insulation purposes and analyzed the performance of each design. The bending characteristics were analyzed in order to identify the flexibility of the welded areas; subsequently, the seam breaking strength and water pressure resistance were analyzed to identify the bonding strength. In addition, two types of waterproof fabric, polyurethane (PU) coated 2 layer and PU laminated 2 layer fabrics, were used for a performance analysis, according to fabric processing specifications. The circle type showed the highest flexibility in the terms of bending characteristics that influence wearability and were followed by the wave and the straight type. In terms of breaking strength, the straight type showed the highest breaking strength, followed by the wave and the circle type. The water pressure resistance analysis found that the wave type was superior to the straight type in terms of water pressure resistance. The wave type is deemed to be a design type suitable for maximizing performance, provided that the issue of stabilization in the welding production process is addressed. Looking at the bending characteristics of waterproof fabric for each specification, the laminating waterproof cloth outperformed the coated waterproof cloth in terms of flexibility. However, in terms of seam breaking strength, the coated waterproof cloth outperformed the laminated cloth. In contrast, the water pressure resistance of the laminated waterproof fabric was found to be higher than the coated waterproof fabric, leading to the conclusion that the bonding strength of the laminated waterproof fabric is higher than that of the coated waterproof fabric based on the assumption of injecting air.

• Fibers and Polymers
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• v.5 no.4
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• pp.316-320
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• 2004

Waterproof fabrics are seamed and sealed by waterproof sealing tape to prevent water from penetrating through the stitch holes. As this process may change the mechanical properties of breathable waterproof fabric related to its deformation with human body, the changes in mechanical properties were investigated. In both of parallel and perpendicular directions, tensile characteristics were remarkably changed with seaming and sealing processes. The increase of LT and WT means that the clothing sealed by waterproofing tape may produce somewhat discomfort feeling. On the other hand, the bridge of the sewing thread seemed to be reinforced by waterproofing tape. Shear characteristics such as G, 2HG, and 2HG5 gradually increased with seaming and sealing processes in parallel direction. However, they decreased with sealing process in perpendicular direction because the seam line would work as an axis located at the center of the testing range.

• KIEE International Transactions on Electrophysics and Applications
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• v.3C no.4
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• pp.146-154
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• 2003

This paper describes various characteristics of the new compounds for cable jackets and model cables advanced in waterproof performance in order to essentially solve the problems of underground (URD) distribution class power cable failures. Several compounds were manufactured by the inclusion of additives to base resins available in Korea and tested for basic property, mechanical and electrical characteristics. Two model cables were created by using the compounds determined in the test as being the most appropriate for new structured model cable jacket material. The waterproof performance and mechanical strength of the new cable jackets were verified by applicable tests. As a result, MDPE and LLDPE compounds were superior as cable jackets in both mechanical and electrical characteristic aspects when compared with conventional PVC. In addition, the model cables composed of the new compounds based on MDPE showed good quality results in the water permeability test.

• Fire Science and Engineering
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• v.17 no.1
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• pp.21-25
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• 2003

This experimental study shows the thermal characteristics of the fire fighter's waterproof clothing exposed to the radiation heat. From the test results, the surface temperature of the fire fighter's waterproof clothing exposed to the radiation with the passage of time sharply increased as the exposed-distance became closer. Also as the radiant heat flux increased, the surface temperature is higher and the time reaching steady state is sharply shorter. As the exposed-distance become more distant, the surface temperature of the fire fighter's waterproof clothing decreased and the difference of temperature between the front side and the back side of the clothing decreased as well. Besides, the radiant heat flux increased, the safety exposed-distance increased. Therefore it is necessary that fire fighter have to work keeping a fixed safe distance from the radiant heat source.

• Resources Recycling
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• v.14 no.4 s.66
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• pp.22-33
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• 2005

Four sheet-shaped and one soft-shaped self-sealing waterproof materials were prepared to recycle some GRT(Ground Rubber Tires). Their physical properties were tested to consider characteristics of them. The self-sealing waterproof materials were consisted of GRT/super absorbent polymer(SAP)/binder and mold by a hot press after mixing with a batch-typed internal mixer. The average size of GRT particles was -40 mesh, SAPs were commercial GE-500F and poly(AM-SAS-AA) prepared in this work. Binders were PU. EVA, LDPE, SBR, and poly(2-EHA). And PU film was attached to improve the properties of waterproof materials. Characteristics of self-sealing waterproof materials consisted of by GRT/GE-500F/EV-600/PU film and GRT/GE-500F/SBR(vulcanization)/PU film among the developed self-sealing waterproof materials were similar to the commercial products. And properties of the soft-shaped self-sealing waterproof materials consisted of by GRT/GE-500F/Po1y(2-EHA) and CRT/Poly(AM-SAS-AA)/poly(2-EHA) were improved within from four times to twenty times compared to the one oi the commercial products.

• Journal of the Society of Disaster Information
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• v.12 no.3
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• pp.242-248
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• 2016

This paper presents features of impermeable asphalt pavement material that uses thermoplastic GMA-based polymer(SIS, Stylene Isoprene Stylene) to improve the waterproof performance. Furthermore, as part of this study, the aerodynamic characteristics of the asphalt paving materials, using the newly suggested thermoplastic polymer, are identified through experiments. In the experiment, the aerodynamic characteristics were analyzed by testing on stability, flow values, porosity, dynamic stability, tensile strength ratio and skid resistance in accordance with KS standard and ASTM standard.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.85-86
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• 2023

This study confirmed the improvement of the Composite Waterproof Method in which the sheet layer is partially attached with perforated film and the joint is FRP-treated.