• Journal of Environmental Science International
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• v.22 no.6
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• pp.687-694
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• 2013

To investigate organoclay, high styrene resin masterbatch (HSR), high impact polystyrene (HIPS), and polystyrene (PS) as reinforcing materials for the improvement of the abrasion resistance of poly(styrene-block-butadiene-block-styrene) (SBS), SBS/organoclay nanocomposites, SBS/HSR, SBS/HIPS, and SBS/PS blends were prepared. The effect of organoclay and blends on the abrasion resistance and mechanical properties of SBS was investigated. Even though intercalations of organoclay are observed for SBS/Cloisite 20A nanocomposites and not for SBS/Cloisite 30B composites, the abrasion resistance of SBS/Cloisite 20A nanocomposites is worse than that of SBS/Cloisite 30B composites. When SBS was blended with HSR, HIPS and PS, the abrasion resistance of the blends increases with increasing of HSR, HIPS and PS content from 0 to 20 wt%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.293-297
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• 1994

The effect of organic acids on growth and heat resistance of Listeria monocytogenes Scott A were investigated. The growth of L. monocytogenes was inhibited in Tryptic Soy Broth(TSB) with 0.1 or 0.2% of acetic , tartic , propionic , citric and lactic acid at 35$^{\circ}C$, respectively. The growth of l. Monocytogenes did not occur in TSB with 0.2% of acetic acid or propionic acid during 48h of incubation. The heat resistance of L.monocytogenes was affected by kind of organic acid, ph and heating substrate. L.monocytogenes showed more heat resistant in TSB with various organic acids than in 0.1M sodium phosphate with the same organic acids. Heat resistance decreased as pH of heating substrate decreased . Surface-adherent microcolony was more heat resistant than planktonic cell of L. monocytogenes. Propionic and lactic acids more affected on heat resistance of L.monocytogenes than acetic , tartaric and citric acids.

• Journal of the Korea Institute of Building Construction
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• v.3 no.3
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• pp.73-81
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• 2003

In this paper, salt damage resistance of high durable concrete was tested. High durable concrete was made by using low water cement ratio, chemical admixture called super-durable admixture and mineral admixtures such as fly-ash, ground granulated blast-furnace slag, silica fume. Two kinds of salt damage resistance test were carried out. One method is chloride ion penetration test(ASTM C1202), and the other one is depth of chloride penetration test in saline solution. Test results were as followers: 1) The depth of chloride ion penetration increased exponentially as water cement ratio was increased and time passed. 2) Super-durable admixture had little effect on the improvement of salt damage resistance of concrete. 3) Silica fume and ground granulated blast-furnace slag were effective on salt damage resistance because of pozzolanic reaction, but fly-ash had a little effect.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.184-185
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• 2013

Concrete filled steel Tube(CFT) columns have great strength but also fire resistance performance due to the heat storage effect of concrete. In this research, we focus on the fire performance of CFT using 100 MPa concrete without fire protection. We use steel fiber and nylon fiber for fire resistance. We perform the fire test of CFT specimen with loading 200, 300 and 400 ton. To investigate the effect of loading to fire resistance, we compare the fire resistance time according to the loading.

• Korean Journal of Metals and Materials
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• v.49 no.10
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• pp.747-753
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• 2011

In order to improve the corrosion resistance of Fe-20Cr-1.7C-1Si hardfacing alloy without a loss of wear resistance, the effect of Ni addition was investigated. As expected, the corrosion resistance of the alloy increased with increasing Ni concentration. The wear resistance of the alloy did not decrease, even though the hardness decreased, up to Ni concentration of 5 wt.%. This was attributed to the fact that the decrease in hardness was counterbalanced by the strain-induced martensitic transformation. The wear resistance of the alloy, however, decreased abruptly with increases of the Ni concentration over 5 wt.%.

• Journal of Korea Multimedia Society
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• v.23 no.10
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• pp.1318-1330
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• 2020

The purpose of this study is to identify the effect of the innovation characteristics that AI Elderly Care Robots have on elderly consumers and to verify the acceptance or mediated resistance by the elderly of the innovation characteristics. Research was conducted throughout this study of the characteristics of the elderly so that the study results could contribute to the improvement of the quality and manufacture of AI Elderly Care Robots by lowering the psychological resistance of the elderly. Survey questions were answered by senior citizens aged 65 and older. The SPSS25 and AMOS22 programs were used for analysis. The analysis confirmed that innovation resistance has a significant mediated effect on the characteristics of elderly consumers and their willingness to accept the innovation characteristics of the AI Elderly Care Robots. Through this study, Ram's innovation resistance model has been verified empirically and it is estimated that by considering the specificities of elderly consumers and using the information to contribute to the development and modification of AI Elderly Care Robots will increase the willingness of the elderly to accept the innovation characteristics of the AI Elderly Care Robots.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.98-103
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• 2009

In this paper, we test the electrical resistance of flat wire in the PV module. normally solar cell has two kind of flat wire(inter connection ribbon and bus bar ribbon). we found the phenomenon that has a unbalance with resistance when we make a wiling between of string. So, we measurement the resistance of flat wire each other. and analysis of missmatch with resistance between flat wires on PV module. next to survey of IR picture on missmatch flat wire samples for analyze of missmatch with current in the wire. and we perform IR test with solar cell that has a connection with flat wire for test the effect of missmatch resistance on solar cell. Finally we perform the Dark I-V test for survey of effect by the unbalance of resistance. By the result of Dark I-V test, the series resistance of existing connection sample is large more then innovated connection sample.

• The Journal of Korean Physical Therapy
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• v.35 no.5
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• pp.132-138
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• 2023

Purpose: This study compared the effects of the elastic resistance and general training for college Taekwondo athletes, and investigated the biomechanical ability and lower extremity function according to the movement speed of the knee joint. Methods: Twenty university student Taekwondo athletes participated voluntarily in this study. The subjects performed general resistance training for four weeks, followed by elastic resistance training for another four weeks. The biomechanical parameters during the fast and slow isokinetic conditions, Y-balance ability, and vertical jump ability were measured three times: before training, after general resistance training, and after elastic resistance training. Statistical analysis was performed under isokinetic conditions and the intervention effect. Results: The biomechanical ability differed significantly between fast and slow isokinetic conditions (p<0.05). An analysis of the training method revealed a significant difference in the maximum knee extension speed and the posterior-lateral direction of the Y-balance test (p<0.05). Conclusion: Elastic resistance training had a more positive effect on the functional task performance than biomechanical factors related to muscular strength compared to general resistance training. In addition, speed-related knee biomechanical information of subjects with strong physical abilities could be utilized in sports physiotherapy.

• International journal of steel structures
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• v.18 no.5
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• pp.1497-1507
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• 2018

Most of previous studies on fire resistance of restrained steel beams neglected creep effect due to lack of suitable creep model. This paper presents a finite element model (FEM) for accessing the fire resistance of restrained high strength Q460 steel beams by taking high temperature Norton creep model of steel into consideration. The validation of the established model is verified by comparing the axial force and deflection of restrained beams obtained by finite element analysis with test results. In order to explore the creep effect on fire response of restrained Q460 steel beams, the thermal axial force and deflection of the beams are also analyzed excluding creep effect. Results from comparison infer that creep plays a crucial role in fire response of restrained steel beam and neglecting the effect of creep may lead to unsafe design. A set of parametric studies are accomplished by using the calibrated FEM to evaluate the governed factors influencing fire response of restrained Q460 steel beams. The parametric studies indicate that load level, rotational restraint stiffness, span-depth ratio, heating rate and temperature distribution pattern are key factors in determining fire resistance of restrained Q460 steel beam. A simplified design approach to determine the moment capacity of restrained Q460 steel beams is proposed based on the parametric studies by considering creep effect.

• The Plant Pathology Journal
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• v.22 no.4
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• pp.339-347
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• 2006

Riboflavin caused induction of systemic resistance in chickpea against Fusarium wilt and charcoal rot diseases. The dose effect of 0.01 to 20 mM riboflavin showed that 1.0 mM concentration was sufficient for maximum induction of resistance; higher concentration did not increase the effect. At this concentration, riboflavin neither caused cell death of the host plant nor directly affected the pathogen's growth. In time course observation, it was observed that riboflavin treated chickpea plants were inducing resistance 2 days after treatment and reached its maximum level from 5 to 7 days and then decreased. Riboflavin had no effect on salicylic acid(SA) levels in chickpea, however, riboflavin induced plants found accumulation of phenols and a greater activities of phenylalanine ammonia lyase(PAL) and pathogenesis related(PR) protein, peroxidase was observed in induced plant than the control. Riboflavin pre-treated plants challenged with the pathogens exhibited maximum activity of the peroxidases 4 days after treatment. Molecular weight of the purified peroxidase was 42 kDa. From these studies we demonstrated that riboflavin induced resistance is PR-protein mediated but is independent of salicylic acid.