• International Journal of Automotive Technology
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• v.6 no.3
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• pp.293-303
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• 2005

Bonded dissimilar materials are being increasingly used in automobiles, aircraft, rolling stocks, electronic devices and engineering structures. Bonded dissimilar materials have several material advantages over homogeneous materials such as high strength, high reliability, light weight and vibration reduction. Due to their increased use it is necessary to understand how these materials behave under stress conditions. One important area is the analysis of the stress intensity factors for interface cracks emanating from circular holes in bonded dissimilar materials. In this study, the bonded scarf joint is selected for analysis using a model which has comprehensive mixed-mode components. The stress intensity factors were determined by using the boundary element method (BEM) on the interface cracks. Variations of scarf angles and crack lengths emanating from a centered circular hole and an edged semicircular hole in the Al/Epoxy bonded scarf joints of dissimilar materials are computed. From these results, the stress intensity factor calculations are verified. In addition, the relationship between scarf angle variation and the effect by crack length and holes are discussed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.5
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• pp.240-248
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• 2020

Over the past 20 years, brain science has developed rapidly thanks to new technologies such as functional magnetic resonance imaging (fMRI), leading to more accurate knowledge of human nature and behavioral changes. This knowledge is also actively applied in the field of management. This research aimed to gain insights into how neuroscience can be incorporated into management through the case of Midas IT Co. This construction software company has a separate organization with the purpose of studying brain science, and it makes and implements human resource management policies based on brain science. The founder Lee Hyung-woo has a humanist management philosophy, and the company's brain science research supports that philosophy. The case study method was adopted as the research method, and procedures such as interviews and direct observation, participation observation, and document information were carried out. The company's human resource management system can be explained by a brain science model called "SCARF", which combines various neuroscience discoveries. As this model suggests, the company has improved the trust and satisfaction of its members by reducing threat of status and by increasing certainty, autonomy, relationship, and fairness in the workplace, resulting in the creation of a platform for creativity, integrity, and high performance.

• Journal of Information Technology Services
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• v.19 no.3
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• pp.151-163
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• 2020

This paper describes a study on the FRACAS(Failure Reporting Analysis and Corrective Action System)-based dependability control platform for domestic urban railway trains. There are more demands for the verification of the dependability of trains as it becomes a regulation for train manufacturers to verify the dependability recently. Train manufacturers as well as railway operators need a effective FRACAS solution to perform the verification of the dependability. Yet current FRACAS solutions have limitations to support the verification processes effectively. This paper addresses the issues of current FRACAS solutions and suggests a FRACAS framework designed for the domestic urban railway trains. Service failure scenarios are standardized using the proposed availability model to implement a more user-friendly and reliable platform. A new FRACAS-based platform for the dependability control (SCARF^®) has been developed to implement the suggested framework. The detail interfaces and functions of the platform are explained. The SCARF^® platform is expected to engage the increasing demands for the dependability control successfully enhancing the reliability, maintainability, availability and safety of domestic urban railway trains eventually.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.12
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• pp.1735-1745
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• 1998

Oil-film surface flow visualizations and three-dimensional flow measurements using a straight five-hole probe have been conducted for a circular impinging jet which is normally oriented to the crossflow in a channel. Throughout the experiments, the ratio of channel height to injection hole diameter, H/D, is fixed to be 1.0, and blowing ratio is varied to be 1.0, 2.0, 3.0 and 4.0. From the surface flow visualizations for both top wall(target plate) and bottom wall, impinging jet region on the target plate can be clearly identified, and for the small value of H/D = 1.0, presence of the bottom wall changes the near-hole flow structure, significantly. The three-dimensional flow measurements show that in the dawnstream region of the injection hole, there exist a pair of counter-rotating vortices, called "scarf vortices", and the strength of the vortices strongly depends on the blowing ratio. In addition, a new flow model in the flow symmetry plane has been proposed for H/D = 1.0.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.5 s.176
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• pp.1203-1214
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• 2000

In this paper, a failure model for co-cured steel-composite tubular single lap joints has been proposed incorporating the nonlinear mechanical behavior of steel adherends and different failure mode s such as steel adherend failure and composite adherend failure. The characteristics of the co-cured steel-composite tubular single lap joint were investigated with respect to the test temperature, the stacking sequence of composite adherend, the thickness ratio of steel adherend to composite adherend, and the scarf ratio of steel adherend. Thus, the optimum design method for the co-cured steel-composite tubular single lap joint was suggested.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.3 s.43
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• pp.181-195
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• 1992

The purposes of this study were to investigate 1) the effect of body exposure and color of a woman's suit on the perception of modesty, and 2) the effect of perceiver's sex and age on impression formed by the function of clothing variables. The instrument of this study consisted of a response scale and stimuli. Thirteen items of 7-point semantic differential scales were developed to measure the perceiver's impression on wearer's modesty. Stimuli were color pictures of a model wearing one of 8 types of suit constructed by a 2 $\times$ 2 $\times$ 2 factorial design. The manipulation of each level of the clothing variables were: color of the suit by black and red, leg exposure by varying skirt lengths to a Chanel-line and mini skirt, and neck exposure by shirt collar blouse and scarf. Two models, representing typical female college students living in Seoul, were selected to eliminate model effect. The sample include 384 subjects, consisting of 4 groups of male and female college students and middle aged men and women. Eight experimental groups were randomly assigned to one of eight stimuli based on between-subject design. One half of each group responded to model 1 and the other half to model 2 of same stimulus. Responses to the semantic differential scales were factor analyzed (pc model, Varimax rotation) to identify factors constructing impression of modesty. Two factors emerged regard­less of subgroups; Elegance and Extroversion factor. The first factor was found to be dominant, accounting for 60 percent of the total variance. The other accounted for just 11 percent. Multidimensional ANOVA (5-way, 3-way) was conducted to test the effect of the clothing variables against two factors identified from the factor analysis. Leg exposure was the most powerful variable affecting the impression of Elegance and Extroversion factor for all per. ceiver subgroups. Neck exposure had primary effect on the impression of Elegance, whereas it partially influenced that of Extroversion. Color of suit had only partial effect on the impression of Extroversion. Hypothesis I was partially supported from the findings above. The effect of perceiver's age and sex on impression by the function of clothing variables was tested by comparing the result between four subgroups. In forming an impression of the wearer's modesty, male college students were least affected by the manipulation of clothing variables, while middle aged males were affected most. In the female groups, there was no age difference and they fell between the male groups in the degree to which they were affected. Hypothesis II was supported only by age difference in two male groups, and by sex difference in two student groups.

• Water for future
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• v.28 no.6
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• pp.147-158
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• 1995

The purpose of this study is to establish a method of estimating the daily urban water demand using statistical model. This method will be used for the development of the efficient management and operation of the water supply facilities. The data used were the daily urban water use, the population, the year lapse and the weather conditions such as temperature, precipitation, relative humidity, etc. Kwangju city was selected for the case study area. The raw data used in this study were rearranged either by month or by season for the purpose of analysis, and the statistical analysis was applied to the data to obtain the regression model. As a result, the multiple linear regression model was developed to estimate the daily urban water use based on the seather condition. The regression constant and the model coefficients were determined for each month of a year. The accuracy of the model was within 3% of average error and within 10% of maximum error. The developed model was found to be useful to the practical operation and management of the water supply facilities.