• International Journal of Highway Engineering
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• v.16 no.4
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• pp.45-50
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• 2014

PURPOSES : The objective of this study is to analyze the performance of anti-stripping agent depending on its type and content to reduce pothole, an increasing pavement distress due to abnormal climate intensity. METHODS : In the past years, U.S and many countries in Europe use hydrated lime and liquid anti-stripping agent in asphalt mixtures. Hydrated lime or liquid anti-stripping agent is substituted for filler and binder, respectively, to improve the anti-stripping property of asphalt mixtures. To investigate this, indirect tensile strength test was performed and TSR values were compared for different content of hydrated lime and types of liquid anti-stripping agent in asphalt mixture. RESULTS : Test results indicate that hydrated lime remarkably increased the asphalt mixture performance on anti-stripping denoted by the increased in TSR values from 55% to 100%. Liquid anti-stripping agent also increased the value of TSR but not significant. In addition, depending on the types of aggregate, TSR values and effect of liquid anti-stripping were different. CONCLUSIONS : Using anti-stripping agents improve the anti-stripping property of asphalt mixture especially hydrated lime; however, more experiments should be conducted to improve the reliability about the effect of liquid anti-stripping agent.

• Journal of Advanced Research in Ocean Engineering
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• v.4 no.3
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• pp.105-114
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• 2018

In the past, traditional methods of research on ship maneuvering performance were estimated in calm waters. However, the course-keeping ability and the maneuvering performance of a ship can be influenced by the presence of waves. Therefore, it is necessary to understand the maneuvering behavior of a ship in waves. In this study, the force acting on a moving ship and a rudder behind the model ship will be performed in regular waves in Changwon National University (CWNU). In addition, the prediction force acting on the rudder in calm waters was carried out and compared with those of Computational Fluid Dynamics (CFD). Model test in regular wave was performed to predict the force acting on the ship and the rudder behind the model ship in various wave directions. The effects of wavelength and wave direction on hydrodynamic forces acting on the ship hull versus rudder angle is discussed.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.4
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• pp.55-63
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• 2002

Meet in the internationalization period recently and van every county is progressing unionization work of every county standard with the Europe, the United States of America. If our county does not correspond actively by age, economical disadvantage is expected. Tested PC, PC monitor, printer and harmonic for device for company business of FAX 4 kinds and flicker occurrence disgrace to achieve and analyze electricity quality test for office appliances by link of confrontation in such current in treatise that see therefore. As result that test printer and PC monitor ware stable but Desktop PC and FAX are presented in valid EN standard to January, 2004 that more than limit higher harmonics and flicker phenomenon appeared, and presented countermove in reply.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4865-4869
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• 2013

Background: The objectives of this present study were to assess the awareness of cervical cancer and its risk factors among female undergraduates in South Africa, and to determine the their level of acceptability of Human Papillomavirus (HPV) vaccination. Materials and Methods: This cross-sectional study was conducted in March 2013 among 440 full time undergraduate female students. Results: Of those students who never had sex (n=163), 96 (58.9%) had ever heard of cervical cancer and only 12 students (12.5%) knew that HPV causes cervical cancer. More than a third (35.4%) of the students correctly said that sexual intercourse before age of 18 years is a risk factor for cervical cancer and 55.2% of the students knew about the Pap smear test which is used for screening cervical cancer. The majority (77.3%) were willing to accept HPV vaccination. Results revealed that students who knew about the Pap smear test, and were aware that having multiple sex partners, sexual intercourse before the age of 18 years, smoking and having contracted any STDs are risk factors for cervical cancer were more likely to accept HPV vaccination compared to other groups. Conclusions: The general knowledge of South African female university students about cervical cancer is not sufficient but they have positive attitudes toward getting vaccinated with the HPV vaccine.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.97-97
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• 2017

This study investigated the corrosion protection by electrodeposited copper layer on AZ31 Mg alloy with and without additional silver layer by immersion test, salt spray test, OCP transient and potentiodynamic polarization experiment. The single electrodeposited Cu layer on AZ31 Mg alloy showed a nodular structure with many imperfections of crevices between the nodules, which resulted in the fast initiation of pitting corrosion within first few hours of immersion. Double-layer coating of Cu and outer Ag layer slightly increased the initiation time for pitting corrosion. Triple-layer coatings of Cu/Ag/Cu exhibited the most efficient corrosion protection of AZ31 Mg alloy, compared to the single- and double-layer coatings. Surface morphology of the outer Cu layer in the triple-layer was changed from the nodular structure to fine particle structure with no crevices due to the presence of an additional Ag layer. Thus, the improved corrosion resistance of AZ31 Mg alloy by electrodeposited Cu/Ag or Cu/Ag/Cu layers is readily ascribed to the decreased number of imperfections in the electrodeposited layers due to the additional silver layer. It is concluded that the additional silver layer provides many nucleation sites for the second Cu plating, resulting in the formation of finer and denser structure than the first Cu electrodeposit.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.332-339
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• 2006

A leaf spring suspension has been widely used since it can carry big load and simplicity. But one major drawback is the poor ride performance because of the friction in the system and the high stiffness coefficient. To overcome these, air spring suspension can be used. The air spring suspension system can improve the ride of the heavy vehicle significantly and also it can adjust the height to the loading and unloading. A truck with the leaf suspension system is modified with the air suspension system and the performance of the vehicle is compared using the suggested method. The existing leaf suspension can be replaced with the air suspension system to improve the performance.

• Journal of Plant Biology
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• v.15 no.1
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• pp.23-27
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• 1972

A total of 163 virus infected pepper plants(Capsicum annuum L.) collected from various pepper growing regions in Korea were investigated on the presence of tobacco mosaic virus (TMV), cucumber mosaic virus (CMV), potato virus X(PVX), potato virus Y(PVY) and alfalfa mosaic virus (AMV) by serological methods. Van Slogteren's microprecipitin test was applied for the testing of TMV, PVX and PVY from infected plants, and Ouchterlony agar double diffusion test was used for CMV and AMV. Results obtained are as follows: 1. TMV, CMV, PVX, PVY and AMV were found to occur on the pepper plants growing in Korea. 2. The prevalence of each of these viruses among the 163 pepper plants investigated was in the order of CMV: 93 plants(57.0%)>TMV: 91 plants (55.8%)>AMV: 58 plants (35.6%)>PVY: 40 plants (24.5%)> PVX:6 plants(3.7%). 3. Among the 163 plants investigated, 72 plants (44%) showed infection with one kind of virus and 91 plants (56%) showed mixed infection with more than two different viruses. In general, heavier damage of the plants was observed from mixed infection. 4. The results of serological identification of pepper viruses coincided with those results obtained by sap inoculation experiment conducted at the Horticultural Experiment Station along with present investigation. Thus the serological techniques applied in this experiment proved to be very reliable for the identification of TMV, CMV, PVX, PVY and AMV from pepper plants infected with these viruses.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.345-351
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• 2020

The study investigates how marketing mix factors are mediated by health consciousness and service quality in creating fresh fruit buying decisions of customers in Vietnam. This study employs samples of customers in Vietnam via the survey questionnaire. The authors have used a total of 256 responses that acquired the valid criteria. The compound of data analysis comprises reliability test, validity test, exploratory factor analysis, group analysis and multiple regression analysis to structure the hypothesized model. Respectively, the structural equation model (SEM) is applied to conduct the multiple multivariate equations. By the assumption of causal-effect relationship between independent variables such as marketing mixed factors, and mediator as health consciousness and service quality, which potentially impact on purchase decision; the SEM method is deployed. The results reveal that consumers have paid no attention to the marketing mix factors, but they care much about service quality and health consciousness. Thus, health consciousness and service quality are effective mediators. These findings are new and contribute to the consumer behavior and retail marketing literature. The findings of this study can provide assistance to managers in the given field to understand more easily the consumer behavior about fresh fruits, then improve their own performance.

• Environmental Engineering Research
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• v.10 no.3
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• pp.112-121
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• 2005

The effectiveness of quicklime-based stabilization/solidification (S/S) in immobilizing lead (Pb) was assessed by performing semi-dynamic leaching tests (ANS16.1). In order to simulate landfill leaching conditions, the ANS 16.1 test was modified by using 0.014 N acetic acid (pH = 3.25) instead of distilled water. Artificial soil samples as well as field soil samples contaminated with Pb were tested. The effectiveness of quicklime treatment was evaluated by determining diffusion coefficients ($D_e$) and leachability indices (LX). A model developed by de Groot and van der Sloat was used to elucidate the controlling Pb leaching mechanisms. Overall, upon quicklime treatment Pb leachability was significantly reduced in a]l of the samples tested. The mean LX values were higher than 9 for an artificial soil sample containing 30% kaolinite treated with 10% quicklime and for a field soil sample treated with 10% quicklime, which suggests that S/S treated soils can be considered acceptable for "controlled utilization". Moreover, quicklime treatment was more effective in artificially contaminated soil with high kaolinite content (30%), indicating the amount of clay plays an important role in the success of the treatment. The controlling Pb leaching mechanism was found to be diffusion, in all quicklime treated samples.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.322-323
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• 2012

This study discussed the formation of phosphate conversion coatings on AZ31 Mg alloy (AZ31) from the zinc phosphating bath with various concentrations of sodium fluoride (NaF). The effects of NaF on the formation, structure, composition and electrochemical behavior of the phosphate coatings were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD) weight balances, open circuit potential (OCP) transients, potentiodynamic polarization curves and immersion test. The coatings were composed of two layers: an outer $Zn_2(PO_4)_3.4H_2O$ (hopeite) crystal layer and an inner amorphous of $MgZn_2(PO_4)_2$. NaF concentration is emphasized to be highly effective in the formation of the hopeite crystal and etching and coating rates. Potentiodynamic polarization and immersion test showed that the coatings formed in the zinc phosphating bath with addition of NaF have much higher corrosion resistance than bare AZ31.