• Journal of the Korean Crystal Growth and Crystal Technology
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• v.26 no.4
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• pp.145-149
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• 2016

The effect of process parameters such as plasma composition, ICP (Inductively Coupled Plasma) source power and rf chuck power on the etch characteristics of GaN epitaxy layer was studied. $Cl_2/Ar$ ICP discharges showed higher etch rates than $SF_6/Ar$ discharges because of the higher volatility of $GaCl_x$ etch products than $GaF_x$ compounds. As the Ar ratio increases in the $Cl_2/Ar$ ICP discharges, the etch anisotropy was enhanced due to the improved physical component of the etching. For both plasma chemistries, the GaN etch rate increased continuously as both the ICP source power and rf chuck power increased, and a maximum etch rate of 251.9 nm/min was obtained at $13Cl_2/2Ar$, 750W ICP power, 400W rf chuck power and 10 mTorr condition.

• Journal of the Korea Convergence Society
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• v.9 no.9
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• pp.1-8
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• 2018

It is a key role in leading and activating coding education as a process to solve problems creatively to produce and provide the educational contents on the basis of 3D printing. In this paper, we develop a variety of fusion contents to use 3D printing and 8bit MCU base control board which provides specific functions through Arduino. The developed control program conducts various packet monitoring more than ten times per a second, supporting intrinsically full duplex. In addition, communication protocol optimized in conveying a lot of information enables to control different contents. The contents produced with the control board and 3D printing are useful as a programming education tool to train the principle and the concept of coding.

• Fibers and Polymers
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• v.6 no.4
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• pp.343-347
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• 2005

The purpose of this study was to investigate the appropriate amounts of phase change materials to give objective and subjective wear sensations. Vapor-permeable water-repellent fabrics with (WR-PCM) and without (WR) octadecane containing microcapsules were obtained by wet-porous coating process. Then, calculating the area of the WR-PCM treated clothes, we estimated the total calories of the clothing by multiplying the heat of fusion and heat of crystallization of PCM to the calculated area. Wear tests were conducted in both warm environment $(30^{\circ}C,\;65\%\;RH)$ and cold environment $(5^{\circ}C,\;65\%\;RH)$ with sports warm up style experimental garments made with WR and WR-PCM fabrics. Rectal, skin, and clothing microclimate temperatures, saliva and subjective evaluation measurements were done during the wear test. There was no difference of rectal and mean skin temperatures between WR and WR-PCM, but the clothing microclimate temperature of WR-PCM under warm environment was slightly lower than that of WR. In cold environment, WR-PCM showed much higher temperature than in WR. Saliva change did not appear between clothes, but did between two environments. Although subjective sensation between WR and WR-PCM was not significantly different, WR-PCM was rated as cooler than WR in warm environment and as warmer than WR in cold environment. The results of this study indicated that octadecane containing microcapsules in water-repellent fabric provide cooling effect.

• Journal of the Korean Society of Costume
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• v.66 no.7
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• pp.124-138
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• 2016

The present study observes collaboration methods in which 3D printing was a part of the fashion manufacturing process, expression methods of such cases, and their ripple effects. As a result, the three types of collaborations between fashion designers and other industry fields, fashion brands and 3D printing companies, and fashion designers and artists. Case analysis results and ripple effects found according to each collaboration method were as follows. First, in collaborations found were between fashion designers and other industry fields, 3D printed fashion works with futuristic images were seen through the fusion of future industries, which claim to support cutting edge digital technology, and creative fashion design. As they were mainly collaborations between automobile industries with cutting edge images or digital related industries and fashion designers, they were expressed as a new form of experimental clothing, and were used as strategies to improve future corporate images of the high tech industry. Second, in collaborations between fashion brands and 3D printing technology businesses, the sporting good brands and the shoe industry attempted to let their products be known through the promotion of functional material or ergonomic technology. While they emphasize practicality by mainly using flexible material, they were mainly proposed as functional sporting goods for famous players or as shoe accessories, so methods are still used for public distribution as brand promoting marketing strategies. Third, with collaborations between fashion designers and artists, creative pieces were shown through the grafting of 3D printing technology, the artistry of artists, and the experimentation of fashion designers. In particular, the innovative value of fashion as art was created through the union of the artistic 3D modeling technology support of artists and the creativity of designers. Like this, 3D printing fashion can graft the cutting edge nature of fashion to other industry fields through collaborations, enhancing pacesetting images, and in the fashion field, it can improve possibilities for innovations in the fashion industry through the support of 3D printing technology businesses and artists, raising expectations towards future human living.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.4
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• pp.413-421
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• 2010

In this study, residual-stress distributions in welds with different strength used in natural gas pipelines are calculated by using finite-element analysis and simulating a realistic welding process. The temperature and residual-stress analysis results are compared with the real fusion profile and the application results of the Fitness-For-Service assessment code, API 579 in order to validate the finite-element analysis model and procedure. Parametric study is performed to assess the effect of welding and material variables such as mechanical strength mismatch, the strength of weld metal, reinforcement, and heat input on the residual stress distributions. Finally, on the basis of the parametric study results, the effects of these variables on residual stress distributions are investigated. In particular, the strength mismatch between base metals has an insignificant effect on residual-stress distributions.

• Journal of Korean Society for Geospatial Information Science
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• v.25 no.2
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• pp.21-29
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• 2017

For the efficient and stable operation of autonomous vehicles or advanced driver assistance systems being actively studied nowadays, it is important to determine the positions of the vehicle accurately and economically. A satellite based navigation system is mainly used for positioning, but it has a limitation in signal blockage areas. To overcome this limitation, sensor fusion methods including additional sensors such as an inertial navigation system have been mainly proposed but the high sensor cost has been a problem. In this work, we develop a vehicle position estimation algorithm using in-vehicle sensors and a low-cost imaging sensor without any expensive additional sensor. We determine the vehicle positions using the velocity and yaw-rate of a car from the in-vehicle sensors and the position and attitude of the camera based on the single photo resection process. For the evaluation, we built a prototype system, acquired test data using the system, and estimated the trajectory. The proposed algorithm shows the accuracy of about 40% higher than an in-vehicle sensor only method.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.7
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• pp.1037-1043
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• 2016

Epigenetic processes in the development of skeletal muscle have been appreciated for over a decade. DNA methylation is a major epigenetic modification important for regulating gene expression and suppressing spurious transcription. Up to now, the importance of epigenetic marks in the regulation of Pax7 and myogenic regulatory factors (MRFs) expression is far less explored. In the present study, semi-quantitative the real-time polymerase chain reaction (RT-PCR) analyses showed MyoD and Myf5 were expressed in activated and quiescent C2C12 cells. MyoG was expressed in a later stage of myogenesis. Pax7 was weakly expressed in differentiated C2C12 cells. To further understand the regulation of expression of these genes, the DNA methylation status of Pax7, MyoD, and Myf5 was determined by bisulfite sequencing PCR. During the C2C12 myoblasts fusion process, the changes of promoter and exon 1 methylation of Pax7, MyoD, and Myf5 genes were observed. In addition, an inverse relationship of low methylation and high expression was found. These results suggest that DNA methylation may be an important mechanism regulating Pax7 and MRFs transcription in cell myogenic differentiation.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.347-350
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• 2006

Today the domestic construction industries are changing. The bigger, higher and more professional are gradually the construction industries, the faster does the fusion into the other industries also undergone. It is gradually needed to estimate the process of the project in the construction industries through this tendency. Consumers or the owner gradually reify their needs and it is essential for an objective appraisal standard to estimate the accomplishment of the project because its level is raised. In this study the problem is understood through the analysis on the existing system of construction industries and it is indicated to new performance measurement system in construction project through the analysis on the influential factors including the qualitative analysis such as consumer satisfaction.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.7
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• pp.1732-1739
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• 2013

The identification of haplotypes, which encode SNPs in a single chromosome, makes it possible to perform a haplotype-based association test with diseases. Given a set of genotypes from a population, the process of recovering the haplotypes that explain the genotypes is called haplotype inference. We propose a new preprocessing algorithm for the haplotype inference by pure parsimony (HIPP). The proposed algorithm excludes a large amount of redundant candidate haplotypes by detecting some groups of haplotypes that are dispensable for optimal solutions. For the well-known synthetic and biological data, the experimental results of our method show that our method run much faster than other preprocessing methods. After applying our preprocessing results, the numbers of haplotypes of HIPP solvers are equal to or slightly larger than that of optimal solutions.

• Korean Journal of Veterinary Research
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• v.56 no.4
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• pp.215-221
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• 2016

Due to the shortage of the fingerling/juvenile mud loach, Misgurnus mizolepis in Korea, these fish have been imported from China. However, the mortality rate during and after their transportation is very high. In this study, we examined various physiological and histological parameters to evaluate the effect of salt treatment on the survival and recovery of mud loaches in holding farms during the quarantine process. Glucose, osmolality, $Na^+$, $Cl^-$, and histological changes were assessed for three different salinities. Non-treated fish (control 0.0%) exhibited lower levels of osmolality, and $Na^+$ and $Cl^-$ concentrations compared with those kept in solar salt solution (0.5% and 1.0%). Glucose levels in control fish were higher than those in fish exposed to 0.5% and 1.0% solar salt solution. Histologically, control fish showed thinner epidermis of skin, branchial hyperplasia and lamellar fusion with an abundance of eosinophilic granule cell-like cells. After solar salt solution treatment, damaged gill structures in the fish almost recovered within 5 days. The present study demonstrates that mud loaches transported from China suffer from skin and gill damage and physiological dysfunction which may increase the mortality and morbidity. Moreover, saline treatment might alleviate the stress responses and ionic/osmotic imbalances, and help heal gill damage.