• Wind and Structures
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• v.19 no.6
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• pp.585-601
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• 2014

The effect of multiple roughness changes close to a building site was examined through three dimensional computational fluid dynamics (CFD) simulations conducted in a virtual boundary layer wind tunnel (V-BLWT). The results obtained were compared with existing wind speed models, namely ESDU-82026 and Wang and Stathopoulos (WS) model. The latter was verified by wind tunnel tests of sixty nine cases of multiple roughness patches, and also with a simplified 2D numerical model. This work extends that numerical study to three dimensions and also models roughness elements explicitly. The current numerical study shows better agreement with the WS model, that has shown better agreements with BLWT tests, than the ESDU model. This is in contrast to previous results of Wang and Stathopoulos, who concluded that CFD shows better agreement with the ESDU model. Many cases were simulated in a V-BLWT that has same dimensions as BLWT used in the original experiment and also in a reduced symmetrical version (S-BLWT) that takes advantage of regular arrangement of roughness blocks. The S-BLWT gives results almost identical to V-BLWT simulations, while achieving significant reduction on computational time and resources.

• Journal of the Optical Society of Korea
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• v.11 no.4
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• pp.162-172
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• 2007

Scanning Laser Optical Tweezers(SLOT) is an optical instrument frequently employed on a microscope with laser being delivered through its various ports. In most SLOT systems, a mechanical tilt stage with a mirror on top is used to dynamically move the laser focal point in two-dimensions. The focal point acts as a tweezing spot, trapping nearby microscopic objects. By adding a mechanical translational stage with a lens, SLOT can be expanded to work in three-dimensions. When two mechanical stages operate together, the focal point can address a closed three-dimensional volume that we call a workspace. It would be advantageous to have a large workspace since it means one can trap and work on multiple objects without interruptions, such as translating the microscope stage. However, previous studies have paid less consideration of the volumetric size of the workspace. In this paper, we propose a new method for designing a SLOT such that its workspace is maximized through optimization. The proposed method utilizes a matrix based ray tracing method and genetic algorithm(GA). To demonstrate the performance of the proposed method, experimental results are shown.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.834-840
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• 2001

Gear is general mechanical elements that used for power transmission between two shafts that interval is comparatively short. and it delivers big power as accurate ratio of speed. The profile of Spur gear which is the most basic factor is divided into Trochoidal fillet curve and Involute curve. Involute curve is used a lot of a shaped curve of machine parts such as a gear, a scroll compressor and a collar of centrifugal pump. However, It is poor to study the modeling of Trochoidal fillet curve and the three dimensions model shaped mathematical curve. This paper describes a mathematical model of profile shifted involute gear. and this model is based on Camus's theory. We draw three dimensions gear have accurate mathematical function using ADS, VisualLISP. and To check accuracy and perfection, we make a program of checking Interference. and use for this study.

• Journal of the Korean Society of Costume
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• v.51 no.8
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• pp.171-183
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• 2001

The purpose of this study was to develop service quality dimension of beauty parolrs in seoul area. The subject consisted of 545 adults with ages ranged between 20 and 30 who had evaluated service qualify dimension on one of the three different types of beauty parlors in seoul. The beauty parlors were classify into three types. Type I is franchised one, type II is located in center of city and type III is close to consumer's residence area. The result was as follows : 1. Four dimensions of the service quality of the beauty parlor were physical aspects(tangibles·accessibility·cleanness), employee aspects(empathy·capability), policy aspects of beauty parlor (management·reputation·credit card), the skill of the hair stylist. 2. To predict comsumer satisfaction. service quality dimensions were as follows : In franchised beauty parlor, the employee aspects(empathy), the policy aspect (reputation), the skill of the hair stylist were should be considered. In beauty parlor in downtown area, Physical aspects(accessibility), the employee aspects(capability), the policy aspects(reputation), the skill of the hair stylist were should be considered. And the beauty parlor in residence area, the employee aspects(empathy), the policy aspects(reputation) were should be considered.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.9
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• pp.499-504
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• 2020

Service quality of any institution is a pull factor for attracting and retaining the customer. The present study examines the customer satisfaction level toward the quality of service offered by the Islamic banks in Oman. It also aims to find out which dimension influences customer satisfaction more concerning the other dimension chosen for the study. To fulfil the need of the study, a structured questionnaire is distributed amongst 100 customers of Islamic banks. The random stratified sampling technique is used for the collection of the data. The collected data is analyzed using the correlation and the multiple linear regression techniques. The result of the study indicates that timely service provided by the banking personnel has a mean score of 4.57, bank staff readiness to serve the customer has a mean score of 4.36, and the security of the banking operation has a mean score of 4.37 occupies the highest rank in their respective dimension chosen for the study. The study reveals that all three dimensions of quality of service represented by Services Reliability, Services Responsiveness and Services Security have a positive and significant correlation with customer satisfaction. The regression results also indicate that all three dimensions influence customer satisfaction of the Islamic banks.

• Tribology and Lubricants
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• v.33 no.6
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• pp.303-308
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• 2017

Most automobile tire companies have not yet considered the geometric information of a road at the design stage of a tire because the topographical characterization of a road surface is very difficult owing to its vastness and randomness. A road surface shows variable surface roughness values according to magnification, and thus, the contact force between the road and tire significantly fluctuates with respect to the scale. In this study, we make an attempt to define a representative value for surface topographical information at multi-scale levels. To represent surface topography, we use a statistical method called power spectral density (PSD). We use the fast Fourier transform (FFT) and PSD to analyze the height profiles of a random surface. The FFT and PSD of a surface help in obtaining a fractal dimension, which is a representative value of surface topography at all length scales. We develop three surfaces with different fractal dimensions. We use finite element analysis (FEA) to observe the contact forces between a tire and the road surfaces with three different fractal dimensions. The results from FEA reveal that an increase in the fractal dimension decreases the contact length between the tire and road surfaces. On the contrary, the average contact force increases. This result indicates that designing and manufacturing a tire considering the fractal dimension of a road makes safe driving possible, owing to the improvement in service life and braking performance of the tire.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.2
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• pp.320-331
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• 2004

This study was attempted to examine male consumers＇suit purchasing Behavior of subdivided groups according to apparel shopping orientation in men＇s suit purchasing and to suggest basic information applicable to marketing. The sample was taken from 705 men who were aged twenties through forties living in and suburbs. A total of 655 questionnaires were used in the final statistical analysis using factor analysis, reliability test, ANOVA, Duncan test, and X$^2$-test. The results of this study were as follows： 1. The dimensions of apparel shopping orientation were composed of economical, brand/store loyalty, fashion consciousness and convenience shopping orientation. 2. The dimensions of apparel store attributes were composed of atmosphere and service, convenient shopping, fashion and sale promotion, price, quality and reputation. 3. Three groups were classified after group analysis of four factors in male consumers＇apparel shopping orientation： group focusing on convenience (47.2％), group focusing enjoyment of shopping(31.0％), and group focusing economic aspects(21.8％). Additionally differences of the three groups were examined according to importance of store attributes, use of information sources, purchasing Behavior, clothing evaluation criteria and demographic variables.

• KIEAE Journal
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• v.11 no.3
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• pp.19-30
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• 2011

This study examined apartment residents' energy-lifestyle, and their energy consumption patterns by energy-lifestyle. The major findings are as follow: 1)In order to identify energy lifestyle, three dimensions - value of life, energy consuming behavior and energy awareness - were defined by literature reviews, and each dimension was tested to define components. 2)The scores of the 14 factors that were defined by factor analysis on the three dimensions of the energy lifestyle were subject to cluster analysis, and then lifestyle was categorized into five groups. G1 is very negative, and indifferent to energy waste or saving at home. G2 is passively carrying out energy saving activities at home, only within their comfort. G3 is aware of energy saving, and more actively keeping energy saving behavior in their everyday lives, while they also show energy waste behavior at the same time. G4 is particularly indifferent to energy costs, and presenting energy squandering behaviors. G5 is better aware of energy saving than other groups, and carrying out energy saving behaviors in their everyday lives. This study would be of help to establish energy saving management and education plans in apartments.

• The Korean Journal of Applied Statistics
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• v.30 no.4
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• pp.555-566
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• 2017

For multivariate datasets with large number of variables, classical dimensional reduction methods such as principal component analysis may not be effective for data visualization. The underlying reason is that the dimensionality of the space of variables is often larger than two or three, while the visualization to the human eye is most effective with two or three dimensions. This paper proposes a working procedure which first partitions the variables into several "latent" clusters, explores individual data subsets, and finally integrates findings. We use R pakacage "ClustOfVar" for partitioning variables around latent dimensions and the principal component biplot method to visualize within-cluster patterns. Additionally, we use the technique for embedding supplementary variables to figure out the relationships between within-cluster variables and outside variables.

• Journal of Agricultural Extension & Community Development
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• v.25 no.3
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• pp.135-148
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• 2018

Sense of community and length of residence are important variables influencing community participation. The study aims to identify the factors influencing community participation on sense of community. Particularly, the study examine the moderating effects on the length of residency between sense of community and community participation. Data were collected from 130 usable questionnaires among residents of rural villages. Results of a factor analysis yielded three dimensions of sense of community which are solidarity, belonging, and emotional intimacy. Results show that all of factors among three dimensions of sense of community have significance for community participation. And length of residency has a positive effects as a moderator between community capacity and community satisfaction. Results also indicated that length of residence has an negative interactional effects with moderator. It means that even though higher belonging, less community participation if people live in longer their community. It was suggested that sense of community and length of residency should be considered in rural community development policy.