• Textile Coloration and Finishing
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• v.16 no.1
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• pp.1-4
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• 2004

This research surveys the twisting and untwisting tensions according to the various processing conditions of belt type texturing such as draw ratio, 1st heater temperature and velocity ratio. The 1st heater temperature was changed from 1606{\circ}C\; to\; 220^{\circ}C$, draw ratio was changed from 1.6 to 1.9 and velocity ratio was changed from 1.4 to 1.8. The twisting and untwisting tensions are measured with the variation of these processing conditions, in addition, the untwisting tension(T2) and tension ratio(T2/Tl) according to the various processing conditions are analysed with the false twist mechanism which is affected to the physical properties of draw textured yams.

• Fashion & Textile Research Journal
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• v.3 no.1
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• pp.25-30
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• 2001

In order to investigate the influence of thread tension on the structure of lockstitch seam, stitch tightness and seam balance ratio are measured at various tensions of needle thread and bobbin thread. The structure of lockstitch was shown in terms of skeleton stitch models to obtain quantitative analysis of stitch tightness. The balanced seam formed to the rectangu1ar stitch model under low bobbin thread tension, but the fabric tightness produced by interlaced needle and bobbin thread under high bobbin thread tension. In this paper, new equation to obtain seam balance ratio was proposed for a lockstitch seam. By using the new equation, the seam balance ratio was not affected by the stitch density and fabric thickness. In order to form the balanced seam, the ratio on tension of needle thread and bobbin thread was about 6:1~7:1 in this experiment.

• KIEAE Journal
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• v.8 no.5
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• pp.61-68
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• 2008

For the recycling of the resources and the preservation of the environment, this study's purpose is to measure flexural behavior of the reinforced concrete beams with the major variables like concrete strength, replacement ratio of the recycled aggregate and the waste foundry sand and the tension reinforcement ratio and to present the data of the recycled aggregate used for the structure design. The experiment on the flexural behavior resulted in the followings. The ultimate strength of recycled R/C beam was manipulated proportionate to the tension reinforcement ratio, however the strength instantly decreased after passing the ultimate load due to the destroyed concrete of the compression side. The deflection at the maximum load varied from the tension reinforcement ratio by 5.5 times. The test specimen with the tension reinforcement ratio less than $0.5{\rho}b$ showed constant curve without change in the load from the yield to the ultimate load in contrast to the distinctive plastic region where the displacement was rising. Although the strain of main tension steel with the reinforcement ratio indicate different, the design of recycled concrete member can be applied for current design code for reinforced concrete structure as the ratio of tension reinforcement district the under the reinforcement ration in a balanced strain condition.

• Textile Coloration and Finishing
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• v.4 no.3
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• pp.91-96
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• 1992

The crystalline character of NaOH and KOH-cellulose complex having different tension ratio was studied using X-ray diffraction analysis. Cellulose crystalline lattices in tension alkali treatment cotton were identified by measuring and indexing the 101, 101, and 002 reflections. According as alkali treatment tension ratio increased on, cellulose gave rise to the formation of I rather than cellulose II. It seemed that a part of the fine structure of cellulose increased orientation with antiparaell and parallel chain crystal structure. The high tension ratio alkali treatment cotton resulted in lower dye sorption and in higher breaking strength and crease recovery.

• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.246-253
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• 2003

Although concrete members are not normally designed to resist direct tension, the knowledge of tensile strength is of value in estimating the cracking load. In general, there are three types of test method for tensile strength ; direct tension test, flexural tension test, and splitting tension test. Though direct tensile strength represents the real tensile strength of concrete, direct tension tests are seldom carried out, mainly because it is very difficult to applicate a pure tension force. The purpose of this paper is to investigate the test methods, effect of aspect ratio, and the size effect on the direct tensile strength. Direct tension test, using bonded end plates, follows RILEM and U.S.Bureau of Reclamation. And other test methods follow ASTM provisions. Four kinds of aspect ratio and two kinds of size effect are tested. Same variables are tested by direct tension test and splitting tension test for comparison between the two test methods. Test results show that direct tensile strength of concrete is more affected by aspect ratio and size than other kinds of strength.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.200-201
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• 2018

The purpose of this study is to evaluate the adhesion in tension of polymer-modified mortars according to curing conditions. From the test results, the adhesion in tension is seriously affected by type of curing conditions compared with type of polymer dispersions or polymer-cement ratios. The maximum adhesion in tension of EVA-modified mortar with polymer-cement ratio of 20% cured by standard condition is about 1.81 times, the cement mortar cured in water. It is apparent that the adhesion in tension of polymer-modified mortars according to raising of polymer-cement ratio is also much more improved irrespective of type of polymer dispersions and curing conditions.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.479-482
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• 1999

The tension stiffening effect, which means the maintaining a part of stiffness after cracking of concrete in tensile, exists at a reinforced concrete member because of the concrete softening and bonding stress between cracks. It is required to consider it for precise analysis and evaluation o structural behavior, due to the possibility of discrepancy between the actual behavior and the analysis without considering the tension stiffening effect. Making and adopting a tension stiffening model is the most simple and effective way for considering it at nonlinear analysis which indicated the estimation from models and experimental results were similar each others. The comparisons on RC beam were, also performed in order to analyzed the influence of concrete strength and steel ratio into the structural behavior. They indicated that the results from analysis estimated quite closely to the test results at low steel ratio, however, overestimated at high steel ratio. The overestimation increase linearly as concrete strength or steel ratio increased.

• Fashion & Textile Research Journal
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• v.6 no.4
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• pp.492-496
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• 2004

Shrinkage properties of drawn textured Poly(trimethylene terephthalate, PTT) yarn, which has been developed recently, were investigated to provide fundamental information for the textile industry. Shrinkage ratio characteristics on PTT yarn with six different count were investigated with tension, dry and wet thermal temperature. In non-tension, the shrinkage ratio were increased to increasing temperature at dry and wet thermal treatment, and in tension, the shrinkage ratio were increased to increasing tension at dry and wet thermal treatment.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.232-233
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• 2017

The purpose of this study is to evaluate the Adhesion in tension of cement mortar according to adding admixtures such as polymer dispersions, blast-furnace slag and fly ash. From the test results, the adhesion in tension is seriously affected by type of polymer compared with polymer-binder ratios and types of admixture. The maximum adhesion in tension of EVA- modified mortar is about 1.46 times, the cement mortar. It is apparent that the adhesion in tension of polymer-modified mortars according to adding two admixtures is much more improved irrespective of polymer-binder ratio.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.3
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• pp.632-640
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• 1997

Changes in surface properties and detergency of sunactant mixtures were investigated in order to study the optimum mixing ratio of anionic and nonionic surfactants by measuring surface tension, interfacial tension, suspendability, and emulsification as a Amction of mixing ratio. Also, surface tension and detergency of the surfactant mixtures were determined with the increase of water-hardness or temperature. The results were as follows: the addition of NPE to anionic surfactant solutions (LAS or SDS) by 0.1 mole fraction remarkably decreased surface tension. NPE (n=15)/anionic surfactant mixtures showed a synergistic effect in lowering interfacial tension and emulsification, but NPE (n=7.5)/anionic surfactant mixtures did not. In suspension stability, however, synergism appeared when LAS or 505 was mixed with both of NPE's. With respect to the hydrophile of NPE, NPE (n=15) was more effective than NPE (n=i.5) in improving suspension stability. Detergency of LAS/NPE mixture changed almost linearly with mixing ratio, but that of SDS/NPE mixture increased remarkably by the addition of 0.1 or 0.2 mole fraction of NPE at all temperatures. As the temperature increased, surface tension of surfactant mixtures decreased and detergency was improved, but their synergistic effect decreased. In hard water, the mixtures showed better detergency than single surfactuant solutions.