• Journal of the Ergonomics Society of Korea
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• v.21 no.3
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• pp.25-34
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• 2002

The road sign in dynamic traffic system is an important element which affects on human cognitive performance on driving. Web-based vision system simulator was developed to examine the cognition time of the road sign in dynamic environment. This experiment the cognition time of the road sign in dynamic environment. This experiment was designed in with-subject design with two factors: vehicle speed and the amount of information of the traffic sign. It measured the cognition time of the road sign through two evaluation methods: the subjective test with vision system simulator and computational cognitive model. In these two evaluations of human cognitive performance under the dynamic traffic environment, it demonstrated that subject's cognition time was affected by both the amount of information of traffic sign and driving speed.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.1
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• pp.91-101
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• 2003

Boryeong Seadike located at southwestern seashore of Korean peninsula completed in 1997. Sluice gate operation can be an important factor to maintain lake water quality and reduce retaining time of pollutants within lake. The lake water quality simulation model, WASPS was adopted and tested to find out proper gate operation timing and discharge amount. From the simulation of sluice gate operation, the results showed that the later the time of discharge for loosing 1 day successively to 6 days, the better the quality of water. Discharge amount showed relatively minor changes of water quality. This means that pollutants flowed into lake from watershed do not have enough time to mix up with deep water when the gate opened at early time. About 3 days delay of discharge caused the dilution effect to stabilize the lake water quality in case of Boryeong freshwater lake.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.3
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• pp.334-339
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• 2005

This study was conducted to test the white bread dough with substitution of 1, 2, 3, 4 and $5\%$ kimchi powder on farinograph, extensograph, amylograph, and pH to find the dough development time, stability, extensibility, resistance to extension, temperature at gelatinization, and temperature at maximum viscosity. Dough with kimchi powder showed less moisture absorption than control. Upon increasing amount of kimchi powder, pH was decreased and dough development time was increased Extensibility of dough showed negative correlation with amount of kimchi powder added Gelatinization temperature increased but maximum viscosity temperature decreased as the amount of kimchi powder increased Overall, the samples with substitution of kimchi powder showed better extensibility than the control sample at the first fermentation.

• Journal of Environmental Health Sciences
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• v.24 no.2
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• pp.145-150
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• 1998

This study was carried out to investigate the loss amount of collection at the different of precipitatation time, high voltage and gas speed. This work has focused on the dependence of the collection efficiency in the collector zone with gas speed and high voltage. This advanced Model is developed by research of the different parameter as the conventionnal modem of study. In order to investigate collection efficiency of electrostatic precipitator, the loss amount of knocking was measured with Monitek-Treubung and the particle size was analyzed by He-Ne laser diffraction spectroscopy.

• Journal of Korean society of Dental Hygiene
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• v.15 no.6
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• pp.1063-1071
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• 2015

Objectives: The purpose of the study is to investigate the quantitative detection of periodontal pathogens before and after scaling by real-time polymerase chain reaction. Methods: Participants were voluntarily recruited at D university, and saliva samples were extracted before and after scaling. Multiple real-time polymerase chain reactions were used to analyze characteristics and the amount of nine kinds of periodontal pathogens; Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Prevotella intermedia, Fusobacterium nucleatum, Parvimonas micra, Campylobacter rectus, and Eikenella corrodens. Results: After scaling, most periodontal pathogens except Eikenella corrodens were significantly decreased in all subjects(p<0.05). In addition, the percentage of microorganisms associated with disease, the microorganism risk index of periodontitis and the prevalence of red complex, orange complex, and Aggregatibacter actinomycetemcomitans was also significantly reduced after scaling(p<0.05). Conclusions: Scaling decreased in the amount of major periodontal pathogens and periodontitis prevalence rate.

• The Journal of Engineering Geology
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• v.18 no.2
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• pp.207-214
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• 2008

We conducted uniaxial consolidation tests in mudstone samples with different clay content, in order to investigate time-dependent deformation and its characteristics. A significant amount of time-dependent strain was observed at a constant stress level immediately after a jump of stress was applied. For a given mudstone, the amount of time-dependent deformation was nearly proportional to the increment of stress, suggesting a linear viscous rheology. The amount of time-dependent strain increases with clay content, implying that clay plays an important role in creep of the unconsolidated mudstone. A power-law model was suitably applied to our results, suggesting that a short-term prediction of time-dependent deformation of the mudstone is tentatively feasible.

• Journal of Elementary Mathematics Education in Korea
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• v.14 no.2
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• pp.421-440
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• 2010

Our country has excessive amount of learning per hour compared with Japan and Singapore. And as there is no consistence for definition of time between grades, it deteriorates understanding of students. Our country teaches students focusing on time algorism whereas Japan and Singapore teaches their students focusing on flow of time. In composing of mathematics textbook in Korea, Japan and Singapore, textbook of our country contains far more of learning compared with the amount designated in textbooks. Textbooks of Japan contains less teaching elements, but instead it contains much activities to expedite time sense As time is distributed in activities of students, it is more important to construct textbooks with experience of students rather than algorism approaches. In addition, textbooks of Singapore contains various examples and clarified concepts compared with those of our country. Like above, time teaching deployment methods of Japan and Singapore gives us good lessons for teaching time in our country, and it is expected be good reference for future development of our textbooks.

• Journal of the Korean Wood Science and Technology
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• v.36 no.3
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• pp.39-46
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• 2008

Repeated impregnation and carbonization processes were performed to prepare high-density woodceramics using a sawdust board. The physical properties were investigated to confirm morphological and structural changes of one-time and two-time phenolic resin-treated and carbonized woodceramics. As comparing between one-time and two-time carbonized woodceramics, the weight and the density of the two-time carbonized woodceramics decreased with an increase of the amount of impregnated phenolic resin. In addition, when the amount of impregnated phenolic resin was about 40% in these woodceramics, the two-time carbonized woodceramics showed higher weight (23.8%) and density (30.0%) than the one-time treatment.

• Journal of Family Resource Management and Policy Review
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• v.17 no.2
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• pp.75-91
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• 2013

This study is focused on the amount of time spent on child care by mothers with preschool children with developmental disabilities. It is designed to find out how much time mothers spend taking care of their children and to identify related factors. The subjects of this study are 162 mothers of children with developmental disabilities residing in Seoul. The findings are as follows: First, mothers with preschool children with developmental disabilities spent 6 hours and 50 minutes per day caring for their children during weekdays and 6 hours and 10 minutes on weekend days. This is double the amount of time spent by the average mother with preschool children. Second, mothers spent much more time caring for their disabled children than they do for their children without disabilities. Third, determinants of a mother's time for caring their disabled child during weekdays were mother's employment, the number of children, and gender of the disabled child. On weekend days, determinants of mother's care time were the number of children and husband's help for childrearing.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.454-457
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• 1997

The purpose of this study is to develop an optimal model, using existing models, that is able to estimate the amount of spatter utilizing artificial neural network in the short circuit transfer mode of gas metal arc (GMA) welding. The amount of spatter generated during welding can become a barometer which represents the process stability of metal transfer in GMA welding, and it depends on some factors which constitute a periodic waveforms of welding current and arc voltage in short circuit GMA welding. So, the 12 factors, which could express the characteristics for the waveforms, and the amount of spatter are used as input and output variables of the neural network, respectively. Two neural network models to estimate the amount of spatter are proposed: A neural network model, where arc extinction is not considered, and a combined neural network model where it is considered. In order to reduce the calculation time it take to produce an output, the input vector and hidden layers for each model are optimized using the correlation coefficients between each factor and the amount of spattcr. The est~mation performance of each optimized model to the amount of spatter IS assessed and compared to the est~mation performance of the model proposed by Kang. Also, through the evaluation for the estimation performance of each optimized model, it is shown that the combined neural network model can almost perfectly predict the amount of spatter.