• Transactions of Materials Processing
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• 제23권8호
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• pp.482-488
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• 2014

Flexible forming technology has advantages in sheet metal forming, because it can be implemented to produce various shaped molds using a single apparatus. Due to this advantage, it is possible to apply it to the manufacture of an aircraft winglet mold. Presently, most aircraft winglets are manufactured from composite materials. Therefore, the mold for the curing process is an essential element in the fabrication of such composite materials. Compared to conventional mold forming, flexible forming has some advantages such as reduced manufacturing cost and uniformity of mold thickness. If the thickness of the mold is consistent, then the heat transfer will occur uniformly during the curing process leading to improved formability of the composite material. In the current study, numerical simulations were performed to investigate the possibility of flexible forming for manufacturing of the winglet mold. In order to match the size of the actual product, the shape of objective surface was divided to fit the dimensions of the apparatus. The results from the numerical simulations are compared with the objective surface to verify the accuracy. In conclusion, the current study confirms the feasibility and the potential to manufacture winglet molds by flexible forming.

• Journal of the Korean Data and Information Science Society
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• 제28권3호
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• pp.709-720
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• 2017

In healthcare and medical research, many important variables have a measurement error such as body mass index and laboratory data. It is also not easy to collect samples of large size because of high cost and long time required to collect the target patient satisfied with inclusion and exclusion criteria. Beside, the demand for solving a complex scientific problem has highly increased so that a semiparametric regression approach could be of substantial value solving this problem. To address the issues of measurement error, small domain and a scientific complexity, we conduct a multivariable Bayesian smoothing under structural measurement error covariate in this article. Specifically we enhance our previous model by incorporating other useful auxiliary covariates free of measurement error. For the regression spline, we use a radial basis functions with fixed knots for the measurement error covariate. We organize a fully Bayesian approach to fit the model and estimate parameters using Markov chain Monte Carlo. Simulation results represent that the method performs well. We illustrate the results using a national survey data for application.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제28권4호
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• pp.256-263
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• 2002

Using the rat's skull, the study on the biodegradability and guided bone regeneration of the chitosan membrane was performed. The results are as follows: 1. The biodegradability of the chitosan membrane could not be confirmed, but after 12 weeks, this membrane did not yet break into small pieces and there was no specific local tissue reaction. 2. It was not certain whether the pore size of this membrane was affected on osteoblastic activity. 3. After 6 weeks, the bony defect area of rat's skull was not completely filled, but on high magnification it showed that the osteoclasts and the osteoblasts were observed in the regenerating area. In conclusion, the chitosan membrane developed in this study was fit for guided bone regeneration.

• Transactions of the Korean Society of Mechanical Engineers A
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• 제24권12호
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• pp.3080-3087
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• 2000

We obtain the mathematical model of the hard disk drive actuator system the system response data of the finite element analysis or experimental results. The model is base on the Rayleigh-Ritz method to approximate the dynamic response of the actuator system. The basic idea is to use the curve-fit technique to obtain the approximation coefficients. It allows the dynamic analysis of the actuator system without resort to the repetitive finite element modeling work. Even though the dynamic characteristics of the system of the system are affected somewhat by the structural modification and the change of the material properties, we can use the modified size and dynamic properties of the actuator system in the mathematical model to some extent. In this study, we express the mathematical model of the simplified rectangular plate first and then proceed to the actual hard disk drive actuator system.

• Asian-Australasian Journal of Animal Sciences
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• 제18권6호
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• pp.772-779
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• 2005

The objectives of this study were to examine problems with using F$_1$ data by simulation, association of marker loci and QTL from crosses of inbred parental lines and to enumerate the preliminary characterization of genetic superiority within inbred parental lines. In this study, the association between markers for QTL used as covariates and estimates of variance components due to effects of lines was investigated through computer simulation. The effects of size of population to develop inbred lines and initial frequencies and magnitudes of effects of QTL were also considered. Results show that estimates of variance components due to line effects are influenced by including marker information as covariates in the model for analysis. Estimates of line variance were increased by adding marker information into the analysis, because negative covariances between effects associated with the markers and the remaining effects associated with other loci existed. However, the fit of the model as indicated by the log likelihood improved by adding more markers as covariates into the analysis. Marker assisted selection will be beneficial when markers explain unexplained genetic difference during selection procedure. Markers can be used to identify QTLs affecting traits, and to select for favorable QTL alleles. To efficiently use genetic markers, location of markers at the genome must be identified. The estimates of variance due to effects of with and without marker information used as covariates in the analysis were investigated. The estimates of line variances were always increased when markers were included as covariates for the model because a negative covariance were existed.

• Journal of the Korean Institute of Telematics and Electronics S
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• 제36S권8호
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• pp.65-80
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• 1999

This paper presents an elegant method, an affine-model based approach, that can qualitatively estimate the information of camera motion. We define various types of camera motion by means of parameters of an affine-model. To get those parameters form images, we fit an affine-model to the field of instantaneous velocities, rather than raw images. We correlate consecutive images to get instantaneous velocities. The size filtering of the velocities are applied to remove noisy components, and the regression approach is employed for the fitting procedure. The fitted values of the parameters are examined to get the estimates of camera motion. The experimental results show that the suggested approach can yield the qualitative information of camera motion successfully.

• Journal of Magnetics
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• 제20권3호
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• pp.246-251
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• 2015

This study was aimed to study the effect of Zn content on the hyperfine parameters and the structural variation of $Ni_{1-x}Zn_xFe_2O_4$ for x = 0, 0.2, 0.4, 0.6, and 0.8. To achieve this, a sol-gel route was used for the preparation of samples and the obtained ferrites were investigated by X-ray diffraction, scanning electron microscopy, and $M{\ddot{o}}ssbauer$ spectroscopy. The formation of spinel phase without any impurity peak was identified by X-ray diffraction of all the samples. Moreover, the estimated crystallite size by X-ray line broadening indicates a decrease with increasing Zn content. This result was in agreement with the scanning electron microscopy result, indicating the reduction in grain growth with further zinc substitution. The room-temperature $M{\ddot{o}}ssbauer$ spectra show that the hyperfine fields at both the A and B sites decreased with increasing Zn content; however, the rate of reduction is not the same for different sites. Moreover, the best fit parameter showed that the quadrupole splitting values of B site increased from the pure nickel ferrite to the sample with x = 0.8.

• The Journal of Korean Obstetrics and Gynecology
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• 제21권2호
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• pp.232-251
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• 2008

Purpose: Obesity is already a major clinical problem in Korea, so obesity prevention and treatment practices are gradually interested in Korean Medicine doctors. Moreover subjective body shape image entered as a important medical topic recently. To make a graph system for clinical tool which based on the Korean national standard physical scale in 30yrs Korean women. Methods: Physical data of the girth of upper arm, abdomen, hip, buttock, flank, calf, and body weight were statistically analyzed, which collected through the fifth national standard physical scale research. And then reviewed those statistical validation. Results: Relationship of the each body scale data and those graphs were fit and right statistically. Conclusion: These new achieved graph system of Korean standard body scales could be adopt as a useful clinical tool for body image related patients such as obesity, PCOD and postpartum patient in 30yrs Korean women.

• Journal of the Korean Society of Clothing and Textiles
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• 제27권7호
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• pp.789-799
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• 2003

The purpose of this study was to find out clothing evaluation criteria and purchase intention according to consumers' shopping orientation and demographic factors when they shop online. The subjects were 240 men and women living in the metropolitan area. For data analysis, factor analysis, cluster analysis, ANOVA, t-test, Duncan test and descriptive statistics were conducted. The results are as follows: 1. Important clothing evaluation criteria were considered in order of price, style, fit, size and product guarantee etc. Purchase intention was showed more highly when products are related to low involvement than high involvement. 2. Consumers with high hedonic and utilitarian shopping orientation considered clothing evaluation criteria more importantly but showed low level of purchase intention in cyber shopping. And consumers with low hedonic and utilitarian shopping orientation considered clothing evaluation criteria less importantly but showed high level of purchase intention in cyber shopping. 3. There were significant differences in evaluation criteria and purchase intention according to demographic variables. Especially women considered evaluation criteria more importantly and had higher level of purchase intention than men.

• Journal of the Korean Society of Clothing and Textiles
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• 제20권1호
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• pp.28-42
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• 1996

The purposes of this sturfy were 1) to examine the difference between cognitive and actual age, 2) to understand apparel shopping orientations and the importance of store attributes related to cognitive age and 3) to identify relationship.; between apparel shopping orientations and importance of store attribute, ; in cognitively younger and older groups For the study, questionnaires were administered to 450 elderly women over 55 years of age. The questionnaires were designed to mea, ;ore apparel shopping orientations (hedonic, store loyal and brand conscious, careful and planned, confidented and independent, and economic shopping), importance of store attributes, cognitive age and demographics. Using a base of 204 women, data was analyzed by using descriptive statistics, t-test and correlation coeffictents. The results of this study weve summarized as follows. 1. The older women saw themselves on average 6. 6 years younger than they really were 77.6% of the respondents blieved themselves to be cognitively younger 2 Cognitively younger women were more hedonic and less carefull and planned than cognitively older women in apparel Shopping. 3. Cognitively older women thought that proximity and private dressing rooms in apparel stores were mote important attributes than cognitively younger women. In terms of apparel store attributes, older consumers placed importances on product quality, fit and size, design suited to their age, attractive price, and the availability to return unsatisfactory products, in orders.