• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.11
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• pp.1733-1740
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• 2010

The analysis of the dynamic behavior of the packaging of a drum washing machine has been carried out under the drop impact conditions. LS-DYNA software is used for performing the finite element analysis, and the validations are performed by comparing with the impact acceleration, effective stress and deformation of cushioned package with high-speed camera during free drop test. By analyzing the cushion characteristics and the design parameters of the original packaging, a packaging with an improved design is developed, and this design is validated on the basis of the results of the distribution test which consists of drop test, vibration test, stacking test, squeez test and so on. The drop impact simulation and analysis methods developed in this study can be adopted to successfully improve the cushioning provided by the packaging and to reduce the cost involved in developing new packaging for drum washing machines.

• Journal of the Korean Data and Information Science Society
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• v.25 no.5
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• pp.1039-1055
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• 2014

The distribution of a test statistic under a null hypothesis depends on the unknown distribution of the data and thus is unknown as well. Conditional tests replace the unknown null distribution by the conditional null distribution, that is, the distribution of the test statistic given the observed data. This approach is known as permutation tests and was developed by Fisher (Fisher, 1935). Theoretical framework for permutation tests was given by Strasser and Weber(1999). The coin package developed by Hothon et al. (2006, 2008) implements a unified approach for conditional inference via the generic independence test. Because convenient functions for the most prominent problems are available, users will not have to use the extremely flexible procedure. In this article we briefly review the underlying theory from Strasser and Weber (1999) and explain how to transform the data to perform the generic function independence test. Finally it was illustrated with a few real data sets.

• Industry Promotion Research
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• v.6 no.1
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• pp.1-7
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• 2021

We investigated multi-layer perceptrons and supervised learning algorithms, and also examined how to model functional relationships between covariates and response variables using a package called neuralnet. The algorithm applied in this paper is characterized by continuous adjustment of the weights, which are parameters to minimize the error function based on the comparison between the actual and predicted values of the response variable. In the neuralnet package, the activation and error functions can be appropriately selected according to the given situation, and the remaining parameters can be set as default values. As a result of using the neuralnet package for the infertility data, we found that age has little influence on infertility among the four independent variables. In addition, the weight of the neural network takes various values from -751.6 to 7.25, and the intercepts of the first hidden layer are -92.6 and 7.25, and the weights for the covariates age, parity, induced, and spontaneous to the first hidden neuron are identified as 3.17, -5.20, -36.82, and -751.6.

• Journal of the Ergonomics Society of Korea
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• v.17 no.3
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• pp.1-11
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• 1998

Focuses of this study are to investigate the usage status of head-restraint system(H/R) in usual driving and to simulate usage conditions of H/R at rear-end crashes. The usage of H/R was categorized into five classes according to the height and distance from occupant's head ; Large-$90^{\circ}$ H/R for enough height and short distance. Large-$70^{\circ}$ H/R for enough height and long distance. Small-$90^{\circ}$ H/R for low height and short distance. Small-$70^{\circ}$ H/R for low height and long distance. and No H/R. Then. these five conditions were tested to find out the degree of neck injuries by using a car-crash simulation package, DYNAMAN. Results from the investigation of H/R usage show that most of drivers(60%) have Small-$70^{\circ}$ H/R for low height and long distance. Results from the simulation performed at 15mph and 30mph show that: 1) at 15 mph, there is a possibility for neck injury in Small-$90^{\circ}$ H/R and Small-$70^{\circ}$ H/R. 2) at 30 mph. there is a high possibility of death in Small-$70^{\circ}$ H/R and Small-$90^{\circ}$ H/R.

• Journal of Technologic Dentistry
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• v.36 no.1
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• pp.17-23
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• 2014

Purpose: The purpose of this study was to analyze and compare the relative accuracy of digitized stone models of lower full arch, using two different scanning system. Methods: Replica stone models(N=20) were produced from lower arch acrylic model. Twenty digital models were made with the white light and blue LED($Medit^{(R)}$, Korea) scanner. Two-dimensional distance between the landmarks were measured on the Delcam $CopyCAD^{(R)}$(Delcam plc, UK). Independent samples t-test was applied for comparison of the groups. All statistical analyses were performed using the SPSS software package(Statistical Package for Social Sciences for Windows, version 12.0). Results: The absolute disagreement between measurements made directly on the two different scanner-based dental digital models was 0.02~0.04mm, and was not statistically significant(P>0.05). Conclusion: The precision of the blue LED optical scanner was comparable with the digitization device, and relative accuracy was similar. However, there still is room for improvement and further standardization of dental CAD technologies.

• Korean Journal of Optics and Photonics
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• v.16 no.4
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• pp.345-353
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• 2005

We proposed a new and cost-effective method fer assembling holographic pickup modules without any high resolution vision system. Assembling was accomplished by adjusting photodiode package only, leading to a low cost, holographic pickup module. Focus and tracking error signals were simply determined by comparing spot sizes and by using the 3 beam method, respectively, based on four-sectional holographic optical elements. In experiment, we assembled a hologram module and estimated performance of the proposed method fur a holographic pickup module used in compact disc system.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.614-615
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• 2005

The use of plastic substrates enables new applications, such as flexible display devices, and other flexible electronic devices, using low cost, roll-to-roll (R2R) fabrication technologies. One of the limitations of polymeric substrate in these applications is that oxygen and moisture rapidly diffuse through the material and subsequently degrade the electro-optical devices. GE Global Research (GEGR) has developed a plastic substrate technology comprised of a superior high-heat polycarbonate ($LEXAN^{(R)}$) substrate film and a unique transparent coating package that provides the ultrahigh barrier (UHB) to moisture and oxygen,chemical resistance to solvents used in device fabrications, and a high performance transparent conductor. This article describes the coating solutions for polycarbonate ($LEXAN^{(R)}$) films and its compatibility with OLED device fabrication processes.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.882-884
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• 2003

In this paper, thermal analysis of Cubicle type Gas Insulated Switchgear(C-GIS) was investigated through experiments and numerical analysis. To predict 3-dimensional temperature and velocity distribution, the commercial package was used. Although some assumptions and simplifications were introduced to simulate the model, results from the computational model were in good agreement with actual temperature rise measurements obtained from experiments.

• Journal of the Ergonomics Society of Korea
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• v.21 no.2
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• pp.47-58
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• 2002

This research suggested the mathematical model (forward kinematics method) to provide the reference points of driver space more easily and accurately in designing the package layout of vehicle interiors. For this purpose, the lengths of body segments of drivers and various joint angles occurred while were used. The length data between joints for the mathematical model were extracted from $SAFEWORK^{\circed{R}}$ as well as 95th percentile male and 5th percentile female body dimensions were utilized. In addition, the angles of body segments were applied on its diverse values within proper ranges in order to compare them each other. the mathematical model in this study was based on the concept of converting polar coordinate system to Cartesian coordinate system so that reference points of driver space were acquired in Cartesian coordinate system after using the segment lengths of drivers and the joint angles of driving postures as an input of polar coordinate system. It is expected that reference points of driver space obtained from this research are helpful to the study on package layout that is appropriate for physical characteristics of drivers.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.3
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• pp.242-250
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• 2006

The purpose of this study was to identify tourist product factor combinations which confer the highest utility to tourists and to establish the relative importance of factors in terms of their contribution to total utility across gender. Among 250 questionnaires, 230 questionnaires were utilized for the analysis. $X^2$ analysis, Conjoint model, Max. Utility model, BTL model, Logit model, K-means cluster analysis, and one-way anova analysis were used for this study. The findings from this study were as follows. First, the Pearson's R and Kendall's tau statistics showed that the model fitted the data well across gender. Second, it was found that total respondents and three clusters regarded taste price as the very important factor across gender. Third, it was found that the male and female tourists most preferred product with light red color, shaped package, and highly pungent taste sold at a cheap price in factory. Fourth, it was found that the male tourists most preferred simulation product with light red color, shaped package, and highly pungent taste sold at a cheap price in factory. The female tourists most preferred simulation product with light red color, shaped package, and mild taste sold at a cheap price in factory. Finally, the results of the study provide some insights into the types of effective product designs that can be successfully developed by marketers.