• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.12
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• pp.1613-1618
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• 2012

The wheel bearing is one of the important parts in a vehicle for translating power and bearing weight. When it is mounted on the knuckle by using bolts, the distortion of the outer ring including the seal mounting point and raceway occurs. In this study, a numerical analysis was performed to analyze the distortion of the outer ring by using a finite element method. The commercial software MSC.MARC was used for this purpose. Elastoplastic and contact analysis were carried out to compute the clamping behavior of the outer ring, bolts, and knuckle. Because the concavity on the flange of the outer ring affects the deformation, its effect was considered. To verify the reliability of this study, the roundness of the outer ring was measured. The experimental results were comparatively in agreement with the computational results.

• Journal of dental hygiene science
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• v.15 no.4
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• pp.518-526
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• 2015

The purpose of this study was to relationship between self-esteem and employment, appearance. This survey was performed on 483 of university students in some regions. The research was performed using a self-reported questionnaire. Self-esteem was higher in the first, fourth grade and college of military science & police administration, college of medical science. Job-seeking stress was higher in the fourth grade and college of global business adminstration, college of medical engineering. Job preparation behavior was higher in the fourth grade and college of rehabilitation & welfare education. Interest in appearance & appearance management behavior was higher in the female, fourth grade, college of global business adminstration. Higher self-esteem group showed significant interactive effects between the job preparation behavior, appearance management behavior. Job-seeking stress has also been investigated as a much higher employment preparation behavior. In conclusion, increasing the self-esteem of education in the college will be able to raise the employment.

• Korean Journal of Remote Sensing
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• v.35 no.5_2
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• pp.831-840
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• 2019

Recently, the span length of long-span bridges is getting longer. As a result, it has been suggested that a new concept called 'super long-span bridge'. In case of super long span bridges, the structure is being complicated and the importance of structural stability is being emphasized. However, until recently, the most commonly used sensors (dual axis clinometer, anemometer, strain gauge, etc.) have got limit about the bridge monitoring. Consequently, we researched the application of a Global Navigation Satellite System (GNSS) to improve the limit of the existing sensors. In this study, the dual axis clinometer, the anemometer and the strain gauge together with the GNSS were used to analyze the behavior of a super-long suspension bridge. Also, we propose the detailed method of bridge monitoring using the GNSS. This study consisted of three steps. First step calculated the absolute coordinates of the towers and the longitudinal axis direction of the study bridge using the GNSS. In second step, through the analysis of the long-term behavior in shortly after construction, we calculated the permanent displacement and evaluated the stability of main towers. Third step analyzed the behavior of bridge by the wind direction and was numerically indicated. Consequently, the bridge measurement using the GNSS appeared that the acquired data is able to easy processing according to the analysis purpose. If we will use together the existing measurement sensors with the GNSS on the maintenance of the super long-span bridge, we figure each error of measurement data and improve the monitoring system through calibration. As a result, we acquire the accurate displacement of bridge and figure the behavior of bridge. Consequently, we identified that it is able to construct the effective monitoring system.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.9 s.252
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• pp.905-912
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• 2006

Experiments in low strain rate methane-air counterflow diffusion flames diluted with $CO_2$ have been conducted to investigate the flame extinction behavior and edge flame oscillation in which flame length is less than the burner diameter and thus lateral conductive heat loss in addition to radiative loss could be remarkable at low global strain rates. The critical mole fraction at flame extinction is examined in terms of velocity ratio and global strain rate. It is seen that flame length is closely relevant to lateral heat loss, and this sheets flame extinction and edge flame oscillation considerably. Lateral heat loss causes flame oscillation even at fuel Lewis number less than unity. Edge flame oscillations are categorized into three: a growing-, a harmonic- and a decaying-oscillation mode. Onset conditions of the edge flame oscillation and the relevant modes are examined with global strain rate and $CO_2$ mole fraction in fuel stream. A flame stability map based on the flame oscillation modes is also provided at low strain rate flames.

• Korean Journal of Human Ecology
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• v.3 no.2
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• pp.101-111
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• 2000

The purpose of this study is to examine needed abilities of Korean apparel merchandisers and to propose a basic design of textbook for an education of Korean apparel merchandisers. For this purpose. the role and needed abilities of Korean apparel merchandisers'. and the contents of other textbooks under same topic were examined. Data of Korean apparel merchandisers'abilities to execute their role were collected by interviewing 7 apparel merchandisers who work for major Korean apparel manufacturers. Korean apparel merchandisers are expected to have following abilities : comprehensive and analytic Judgement. knowledge of clothing and textiles. deep understanding of the apparel market, budget planning and accounting. cooperation in the execution of tasks, ability of summarizing data, healthcare, and computing skills. The textbook is divided into five parts. The titles and brief description of them are as follows : Part I - Introduction Basic concept and composition factors of apparel merchandising and the role of apparel merchandisers in Korean apparel industry will be discussed. Part II - Apparel Merchandising Environment The structure of apparel manufacturers and apparel industries In Korea. other environmental factors, and apparel consumer behavior will be investigated. Part III - Apparel Market Analysis Market segmentation. brand evaluation, product positioning. target market strategies, and market research will be investigated. Part IV- Apparel Merchandising Apparel merchandising processes will be introduced and explained in detail. Part V - Global Apparel Merchandising Global apparel merchandising environment and strategies. and global sourcing and marketing will be discussed.

• Corrosion Science and Technology
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• v.19 no.4
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• pp.174-188
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• 2020

Atmospheric corrosion is a natural surface degradation process of metal due to changes in environmental parameters in the surrounding atmosphere. It is very sensitive to environmental parameters such as temperature, relative humidity, sulphur dioxide, and chloride, making it a major global economic challenge. Existing forecasting empirical corrosion models including the ISO standard are based on statistical analysis of experimental studies without considering the behavior of atmospheric parameters. The present study proposes a reliable global empirical model for estimating short and long-term atmospheric corrosion rates based on environmental parameters and corrosion mechanisms obtained from a parametric study. Repercussion of atmospheric corrosion rate due to individual and combined influences of environmental parameters specifies their importance in the estimation. New global empirical coefficients obtained for environmental parameters are statistically established (R² =0.998) with 95% confidence limit. They are validated using experimental datasets of existing studies observed at 88 different continental locations. The current proposed model can predict atmospheric corrosion by means of corrosion formation mechanisms influenced by combined effects of environmental parameters, further abating applicability limitations of location and time.

• Structural Engineering and Mechanics
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• v.58 no.4
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• pp.731-743
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• 2016

Plastic behaviors, based on the von Mises yield criterion, of circular discs containing a purely elastic, circular inclusion under uniform temperature loading are studied with the finite element analysis. Temperature-dependent mechanical properties are considered for the matrix material only. In addition to analyzing the plane stress and plane strain disc, a 3D thin disc and cylinder are also analyzed to compare the plane problems. We determined the elastic irreversible temperature and global plastic collapse temperature by the finite element calculations for the plane and 3D problem. In addition to the global plastic collapse, for the elastically hard case, the plane stress problem and 3D thin disc may exhibit a local plastic collapse, i.e. significant pile up along the thickness direction, near the inclusion-matrix interface. The pileup cannot be correctly modeled by the plane stress analysis. Furthermore, due to numerical difficulties originated from large deformation, only the lower bound of global plastic collapse temperature of the plane stress problem can be identified. Without considerations of temperature-dependent mechanical properties, the von Mises stress in the matrix would be largely overestimated.

• Human Ecology Research
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• v.55 no.2
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• pp.105-124
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• 2017

The recent global economic crisis has resulted in increased discussion and attention on the sharing economy, a form of economic activity where individuals share currently available products. This study investigates consumer sharing economy usage attitudes and usage intentions by applying rational choice theory. For this study, an investigation that had 400 adult consumers from across Korea answer a structured questionnaire was conducted. A statistical approach using SPSS ver. 22.0 was used to analyze the data. The study found that the consumer's sharing economy value and participation levels were higher than usual. Higher than usual consumption patterns were seen for the construct of rational behavior theory. An analysis of the relative influence of variables regarding sharing economy usage intention also found that usage intention was higher for those who had experienced using a sharing economy services rather than those who did not have experience. In addition, the sharing economy usage intention also increased along with the values for subjective norms, sharing economy usage attitudes, sharing economy participation, sharing economy emotional benefits, and increased values. This study found that fundamental materials for consumer education should be made to eliminate difficulties that consumers have when they use sharing economy services. It is also expected that economic policy will develop to stimulate the sharing economy in a stable manner, that sharing economy-related information will be provided to consumers, and that consumer policies will be prepared to prevent consumer problems before they occur.

• Structural Engineering and Mechanics
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• v.68 no.5
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• pp.549-561
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• 2018

Sobol method is applied as a powerful variance decomposition technique in the field of global sensitivity analysis (GSA). The paper is devoted to increase convergence speed of the extracted Sobol indices using a new proposed sampling technique called genetic based Latine hypercube sampling (GBLHS). This technique is indeed an improved version of restricted Latine hypercube sampling (LHS) and the optimization algorithm is inspired from genetic algorithm in a new approach. The new approach is based on the optimization of minimax value of LHS arrays using manipulation of array indices as chromosomes in genetic algorithm. The improved Sobol method is implemented to perform factor prioritization and fixing of an uncertain comprehensive high speed rotor-bearing system. The finite element method is employed for rotor-bearing modeling by considering Eshleman-Eubanks assumption and interaction of axial force on the rotor whirling behavior. The performance of the GBLHS technique are compared with the Monte Carlo Simulation (MCS), LHS and Optimized LHS (Minimax. criteria). Comparison of the GBLHS with other techniques demonstrates its capability for increasing convergence speed of the sensitivity indices and improving computational time of the GSA.

• Korea Trade Review
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• v.44 no.6
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• pp.327-344
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• 2019

This paper explores the hub-and-spoke system as the structure of the global economic network that presents obstacles for international cooperation. With its exclusive jurisdiction and control over the hub, a powerful state can employ coercive economic measures to compel and deter unwanted behavior of rogue states and even its allies. Against this backdrop, this study analyzes the cases of the US blocking access to its market by Chinese Huawei as well as the case of Japan in restricting trade for highly advanced goods to South Korea. This analysis reveals that both measures are forms of secondary boycotts, which affect not only the entities within their jurisdiction but also others located in third countries. In addition, this paper extends its findings to free trade agreements and offers implications on the outward processing scheme for the Gaeseong Industrial Complex in the KORUS FTA and the Korea-China FTA. These events result in a gray-risk for South Korea, a country that aims to resolve North Korea's denuclearization and inter-Korean economic cooperation.