• The Journal of Engineering Geology
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• v.25 no.2
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• pp.179-188
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• 2015

Although permeating injection is ideal for grouting reservoir embankments, it is usually combined with fracturing injection for grouting, which can disturb the original soil. Compaction with low expansive pressure followed by grout injection can overcome this problem. An expansive compaction (EC) packer was developed in this work to easily apply sequential injection and compaction at a work site. Furthermore, to achieve compaction around the grouting hole, a mixture of expansive admixtures and grout was injected with the EC packer to trigger an increase in volume of the grout material. This work verifies the compaction effect of the EC packer and the expansive admixture. It reports the concepts of the EC packer, the range of expansive compaction, the effectiveness of injection, and the results of indoor tests performed to verify the effectiveness of the expansive admixtures. The indoor testing comprised a preparatory test and the main test. The preparatory test assessed the admixtures for their compaction effects, while the main test measured and analyzed the admixtures' expansive force, pressure, and compaction effect with a mold to verify the effectiveness of the compaction effect.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.5
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• pp.1137-1143
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• 1994

Through the numerical analysis of the capillary pressure-based Richards equation with and without the effect of the capillary hysteresis under the boundary condition having an antecedent rainfall. the moving tendency of the wetting front, the redistribution of the moisture content, infiltration rate, cumulative infiltration etc, were computed. The effect of the capillary hysteresis cannot be neglected in analyzing an unsaturated flow, and the more accurate results may be obtained by the consideration of the hysteresis effect. If the effect of the hysteresis cannot be considered, the analysis by the use of the main wetting curve may give more reliable result than that of the main drying curve.

• Advances in aircraft and spacecraft science
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• v.4 no.4
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• pp.401-419
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• 2017

This paper presents the main outcomes of the preliminary development of the Anuloid, an innovative disk-shaped VTOL aircraft. The Anuloid has three main features: lift is provided by a ducted fan powered by a turboshaft; control capabilities and anti-torque are due to a system of fixed and movable surfaces that are placed in the circular internal duct and the bottom portion of the aircraft; the Coanda effect is exploited to enable the control capabilities of such surfaces. In this paper, results from CFD analyses and wind tunnel tests are presented. Horizontal and vertical flights were considered, including accelerated flight. Particular attention was paid to the experimental analysis of the Coanda effect via a reduced scale 3D printed model. The results suggest that the Coanda effect is continuously present at the lower surface of the Anuloid and may be exploited for the control of the aircraft. Also, very complex 3D flows may develop around the aircraft.

• Journal of the Korean Home Economics Association
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• v.49 no.10
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• pp.71-79
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• 2011

When adolescents undergo the period of transition, they need to promote self-confidence from social support by parents, teachers or friends. It was believed that boosting subjective perception on their main areas of interest such as academic performance, appearance and fashion will result in happiness. The main purpose of this study was to investigate the influence of social support including family support, teacher support and friend support on self management, appearance satisfaction and fashion opinion leadership. A total of 412 questionnaires from the middle and high school students living in or near Seoul were collected and analyzed. The results indicated that teacher support and family support had a positive effect on self-management and family support had a positive effect on appearance satisfaction. Furthermore, friend support had a positive effect on fashion opinion leadership. In conclusion, implications for promoting self-confidence related to self-management, appearance satisfaction and fashion opinion leadership with the help of social support are suggested.

• The Journal of Korean Physical Therapy
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• v.19 no.3
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• pp.11-17
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• 2007

Purpose: The purpose of this study were to analyze fatigue patterns of the rectus femoris muscle by isometric contraction. Methods: Twenty healthy subjects(10 male, 10 female) participated in this study. Maximal voluntary isometric contraction(MVIC) was measured by the dynamometer. Muscle activity was recorded from the rectus femoris muscle. During the experiment, the subject was seated in the chair. The measured items, median frequency(MDF) and root mean square (RMS), were collected from the surface EMG. All data were analyzed using repeated measures ANOVA. Results: There was significant difference of MVIC between male and female. Endurance time was significant difference by the level of MVIC but no significant in the main effect(sex) and interaction effect. The MDF and fatigue index were significant differences in the interaction effect. The RMS was not significant difference in both of main and interaction effect. The muscle fatigue patterns of female was greater than male after 60% MVIC. Conclusion: This study showed that sex differences of muscle fatigue were started from 60% MVIC.

• Culinary science and hospitality research
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• v.14 no.2
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• pp.205-214
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• 2008

The purpose of this study was to measure the moderating effect of belief homogeneity on the relation-ships among attitudinal ambivalence, behavior intention and consumption behavior. The questionnaire, which consisted of items to measure the constructs of belief homogeneity, attitudinal ambivalence, behavior intention and consumption behavior, were completed by 338 subjects in Jeonnam area. Moderated regression analysis was used to measure the moderating effect of belief homogeneity. To test validity and reliability of constructs, factor analysis and Cronbach's $\alpha$ were used in this study. Results of the study demonstrated that the moderated regression analysis result for the data also indicated a better model fit in Model 2 than Model 1. In the Model 1, the main effects of behavior intention and attitudinal ambivalence on consumption behavior were statistically significant. In the Model 2, the main effects of behavior intention, belief homogeneity and attitudinal ambivalence on consumption behavior were statistically significant. The interactional effects of belief homogeneity$\times$attitudinal ambivalence on consumption behavior were statistically significant. Moreover, the effects of attitudinal ambivalence on consumption behavior were statistically significant at all levels of belief homogeneity, except for when homogeneity was high.

• Korean Journal of Child Studies
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• v.8 no.2
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• pp.45-60
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• 1987

This research examined children's perception of parental authority within three different types of rules : moral, social-conventional, and personal issue. Specifically, two major aspects of parental authority-legitimacy and obedience-were explored. The subjects of this study were 120 children from an elementary school in Kwangju. There were 40 subjects (20 males and 20 females) in each of three age groups: 7-, 9-, and 11- year-olds. The subjects were administered an interview individually. Based on Tisak (1986) open-ended questions concerning three family rules (moral rule, social-conventional rule, personal issue) were administered. Responses to the assessment questions were coded as positive or negative. Responses to the judgment conception questions were coded into 7 categories : Other's Walfare, Social Coordination, Personal choice, Deservedness of Punishment for Wrongdoing, Existence of Authority, Conflicting Personal Interest and Authority, and Personal Development. Statistical analysis of obtained data was by percentage and ${\chi}_2$ test using log linear procedure. The results were as follows : (1) There was a significant main effect of type of rule on the children's assessment regarding legitimacy and obedience of parental authority. The children (average 96%) stated that it was all right for parents to make rules prohiliting an act when it pertained to moral and social conventions. However, the majority of the children (average 40%) stated that it was not right for parents to regulate personal issues. (2) There was a significant interaction effect between type of rule and age. (3) There was a significant main effect of rules on the children's judgment conception of parental authority. (4) There was a significant interaction effect between rules and ages on children's judgment conception of parental authority.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.79.3-80
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• 2016

We have investigated the correlation analysis between global temperature anomaly and two main factors: geomagnetic activity (aa index) of Earth external factor and CO2 of Earth internal factor. For this, we used NOAA Global Surface Temperature anomaly (Ta) data from 1868 to 2015. The aa index indicates the geomagnetic activity measured at two anti-podal subauroral stations (Canberra Australia and Hartland England) and the CO2 data come from historical ice core records and NOAA/ESRL data. From the comparison between (Ta) and aa index, we found several interesting things, First, the linear correlation coefficient between two parameters increases until 1985 and then decreases rapidly. Second, the scattered plot between two parameters shows a boundary of the correlation tendency (positive and negative correlation) near 1985. A partial correlation of (Ta) and two main factors (aa index, CO2) also shows that the geomagnetic effect (aa index) is dominant until about 1985 and the CO2 effect becomes much more important after then. These results indicate that the CO2 effect become very an important factor since at least 1985. For a further analysis, we simply assume that Ta = Ta(aa)+Ta(CO2) and made a linear regression between (Ta) and aa index from 1868 to 2015. A linear model is then made from the linear regression between energy consumption (a proxy of CO2 effect) and Ta-Ta(aa) since 1985. Our results will be discussed in view of the prediction of global warming.

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.345-349
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• 1985

The textural properties of acorn flour gels were investigated with the variations in the concentraction, storage time and storage temperature by the use of Instron Universal Testing Machine. The experimental design was $3^3$ factorial experiment. TPA curves of acorn flour gels showed two sharp peaks in the first bite and no negative peak. The hardness and brittleness of acorn flour gels were very significantly affected by concentration, storage time and storage temperature. For the height difference between first peak and second peals, the main effects for concentration and storage temperature were very significant and the main effect for storage time was not negligible. For bend, the effect of concentration was more significant than the effect of storage temperature, and storage time effect was negligible. Springiness was affected only by the concentration.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.1
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• pp.99-107
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• 2008

There are being a lot of studies for achievement of high speed Dehydration, high-strength and Lightweight of washing machine in the latest washing machine business. It is essential that strength of mechanical press-Joining (MPJ) for spin drum is improved to attain that target. MPJ of spin drum is composed of seaming and caulking process. Because Seaming process of MPJ has various design factors such as thickness, bending radius, seaming width, caulking press width and the dynamic factor such as multistage plastic working, elastic recovery, residual stress, the optimum conditions can't be easily determined. Using a design of experiment (DOE) based on the FEM (Finite Element Method), which has several advantages such as less computing, high accuracy performance and usefulness, this study was performed investigating the interaction effect between the various design factor as well as the main effect of the each design factor during drum MPJ and proposed optimum condition using center composition method among response surface derived from regression equation of simulation-based DOE.