• Korea-Australia Rheology Journal
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• v.18 no.1
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• pp.15-24
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• 2006

The first international inter-laboratory study, involving six laboratories, has been conducted to examine issues associated with yield stress measurements in suspensions. The initial focus of the project was to evaluate the reliability and reproducibility of several common yield stress measuring techniques employed in different laboratories and with different instruments. Aqueous suspensions of colloidal $TiO_2$ at concentrations of 40-70 wt% solids were used as the test fluids. A wide range of instruments and techniques employing both direct and indirect methods were used to determine the yield stress of the samples prepared according to a prescribed procedure. The results obtained indicated that although variations of results existed among different techniques, direct yield stress measurements using static methods produced more reliable and repeatable results than other methods. Variability of the yield stress measured using different techniques within any laboratory however was less significant than variability of the results among different laboratories. The nature and condition of the test suspensions was identified as the most likely factor responsible for the poor reproducibility of yield stress measurements from different laboratories.

• 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.

• Tunnel and Underground Space
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• v.19 no.5
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• pp.421-431
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• 2009

As an indirect method, Schmidt hammer test has been employed to investigate correlation between uniaxial compressive strengths and blow values. To conduct the experiment, researchers have examined 11 types (1,417 blocks) of rock, which include igneous, metamorphic and sedimentary rocks in Korea. Every kind of rocks shows different blow behaviors in which correlations of rocks have been analyzed, thus leading to results in new formulas for strength predictions. Cross-check for reliability demonstrates high confidence. Newly proposed test method is highly valued for future research on Korean rocks.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.4
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• pp.685-700
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• 2016

This study investigated the effects of experience elements on store identity, shopping satisfaction, and behavioral intention in lifestyle shops. The respondents of the study were 300 adult males and females who visited lifestyle shops. The data were analyzed by using SPSS 18.0 for exploratory factor analysis and reliability analysis, and AMOS 18.0 for confirmatory factor analysis and path analysis. The results showed that there were four experience elements: entertainment, education, escapist, and esthetic. The experience elements are based on Pine & Gilmore's Experience Economy Theory. The result of path analysis showed that the entertainment experience and escapist experience had significant influences on store identity. Store identity positively influenced shopping satisfaction, but it had no significant influence on behavioral intention. Shopping satisfaction was found to have a significant effect on behavioral intention. The indirect effect analysis showed that the entertainment and escapist experiences have positive influences on shopping satisfaction and behavioral intention mediated by store identity. The store identity had an influence on behavioral intention mediated by shopping satisfaction. This study provides helpful information to domestic lifestyle brands for the establishment of a competitive store identity strategy by implementing the important store experience elements of lifestyle shops.

• Journal of the Korean Home Economics Association
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• v.49 no.5
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• pp.59-70
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• 2011

The purpose of this study was to examine the effects of family economic distress, paternal depression, marital relationship, and controlling parenting style on behavioral problems in young children and to present a program for their reduction. The participants of this study were 344 fathers, whose young children were attending kindergartens located in Cheongju city. Data were analyzed using descriptive statistics, frequency, factor analysis, reliability analysis, and Pearson's productive correlation, t and F-tests via the SPSS 12.0 program, with the path model analyzed using the AMOS 7.0 program. There were six paths where family economic distress, mediated by paternal depression, marital relationship, controlling parenting style, had effects on the behavioral problems in young children. However, the path where family economic distress had an indirect effect on the behavioral problems in young children via paternal depression and marital relationship appeared to be the most influential. Also, paternal depression appeared to have the most impact on young children's behavioral problems.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.6
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• pp.46-53
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• 2004

Heat release analysis is a very important method for understanding the combustion phenomena inside an engine cylinder. In this study, one-zone heat release analysis was used with the measured cylinder pressures of a HSDI(high speed direct injection) and IDI(indirect injection) diesel engines, Those have benefits of simple equation, fast speed, reliability. The objective of the study is to compare the combustion characteristics between a HSDI and an IDI. The result shoes that the maximum heat release rate of a HSDI is higher than that of an IDI because of long ignition delay period. The heat release curve of an IDI is more linear than that of a HSDI, thus is similiar to that of a SI engine. The combustion efficiency of a HSDI is higher than that of an IDI because of the smaller heat transfer loss of a HSDI. There is a suggestion here that an IDI engine has broad heat transfer area which include two combustion chambers, the connection passage of combustion chambers, etc.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.381-391
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• 2020

This research article investigates the way eWOM in social media influences the formation of destination image through development of trust and satisfaction for the potential tourist. The research involved administering an 18-point questionnaire taking online reviews, tourist involvement, and eWOM, destination image components of trust and satisfaction as variables. Data was collected from 554 individuals forming a cross-section of social media users and analyzed using multi-variate techniques (Reliability, CFA, and SEM). Results indicate a positive and significant relationship between all except online review and destination trust and satisfaction. Indirect and direct effects indicate that eWOM fully mediates the relationship between destination satisfaction and involvement and partially mediates the relationship between destination trust and involvement. In the case of online reviews, eWOM acts as a full mediator between destination trust and destination satisfaction for the future traveler using social media. The study proposes that components of image vary depending upon the degree of involvement, volume online reviews and eWOM generated also termed as 'virality' and these in turn influence the intention to revisit or recommend a destination. The study highlights its utility for National Tourist Organizations (NTOs) and online travel intermediaries to enhance destination marketing efforts.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.1
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• pp.31.1-31.1
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• 2013

Barred-spiral galaxies possess double patterns: a bar and spiral arms. While their angular speeds play an important role in governing gas dynamical evolution of barred spiral galaxies, there is no direct way to observe them. The Tremaine-Weinberg (TW) method has been one of the most reliable indirect methods to estimate pattern speeds, although it requires a few strict assumptions, notably one that the gas tracer is in a quasi-steady state. In barred-spiral galaxies, however, non-steady gas flows are significant especially when the double patterns have different angular speeds. Using numerical models, we explore the effect of non-steady gas motions on the determination of double pattern speeds based on the TW method. We find that the TW method is accurate within 15% when there is only a single pattern or when double patterns have the same angular speed. When double patterns have different speeds, on the other hand, neglecting the non-steady flows leads to quite large errors (> 30%) in the derived pattern speeds, and severely underestimate the real values for the viewing angle parallel to the bar minor axis. This suggests that one should be cautious when applying the TW method to galaxies with double patterns with different speeds.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.6
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• pp.21-30
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• 2005

Heat release analysis is a very importent method in understanding the combustion phenomena inside an engine cylinder. In this study, one-zone heat release analysis was used with the mesured cylinder pressures of an IDI(indirect injection), a HSDI(high speed direct injection) and a SI(spark ignition) engine. It has benefits of simple equation, fast speed, reliability. The object of the study is to compare the combustion characteristics among an IDI, a HSDI and SI engine. Result of analysis, the maximum heat release rate of a HSDI is higher than an IDI because of long ignition delay period. The heat release curve of a IDI is more linear than an HSDI, so the combustion characteristics of a IDI is similiar to that of an SI engine. There is a suggestion here that the combustion efficiency of a HSDI is highest of that of all engines because of the smallest heat transfer loss of all engines.

• Journal of Power Electronics
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• v.5 no.3
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• pp.173-179
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• 2005

In this paper, a very low cost and robust sensing method for the rotor position of a TSRM(Toroidal Switched Reluctance Motors) is described. Position information of the rotor is essential for SRM drives. The rotor position sensor such as an opto-interrupter or high performance encoder is generally used for the estimation of rotor position. However, these discrete position sensors not only add complexity and cost to the system but also tend to reduce the reliability of the drive system. In order to solve these problems, in the proposed method, rotor position detection is achieved using voltage waveforms induced by the time varying flux linkage in the search coils, and then the appropriate phases are excited to drive the SRM. But the search coil's EMF is generated only when the motor rotates. Therefore the rotor position sensing method using squared Euclidean distance at a standstill is also examined. The simulation and experimental results are presented to verify the performance of the proposed method in this paper.