• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.41-41
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• 1998

Rare earth metal films have been used as a buffer layer for growing ferroelectric t thin film or a seed layer for magnetic multilayer. But when it was deposited on s semiconductor substrates for the application of magneto-optic (MO) storage media, it i is difficult to exactly measure magnetic cons떠nts due to shunting current, and so it n needs to grow metal films on insulator substrate to reduce such effect. Recently, it w was reported that ultra-thin Pt layer were epitaxially grown on A12O:J by ion beam s sputtering in 비떠 high vacuum and it can be used as a seed layer for the growth of C Co-contained magnetic multilayer. In this stu$\phi$, Pt thin film were epi떠xially grown on AI2D3 ($\alpha$)OJ) by RF magnetron s sputtering. The crystalline structure was analyzed by transmission electron microscope ( (TEM) and Rutherford Back Scattering (RBS)/Ion Channeling. In TEM study, Pt was b believed to be twinned on AI잉3($\alpha$)01) su$\pi$ace about Pt(ll1) plane.Moreover, RBS c channeling spectra showed that minimum scattering yield of Pt(111)/AI2O:J(1$\alpha$)OJ) was 4 4% and Pt(11J)/AI2D3($\alpha$)OJ) had 3-fold symmetry.

• IEMEK Journal of Embedded Systems and Applications
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• v.19 no.3
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• pp.151-158
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• 2024

Although on-device artificial intelligence (AI) has gained attention to diagnosing machine faults in real time, most previous studies did not consider the model retraining and redeployment processes that must be performed in real-world industrial environments. Our study addresses this challenge by proposing an on-device AI-based real-time machine fault diagnosis system that utilizes continual learning. Our proposed system includes a lightweight convolutional neural network (CNN) model, a continual learning algorithm, and a real-time monitoring service. First, we developed a lightweight 1D CNN model to reduce the cost of model deployment and enable real-time inference on the target edge device with limited computing resources. We then compared the performance of five continual learning algorithms with three public bearing fault datasets and selected the most effective algorithm for our system. Finally, we implemented a real-time monitoring service using an open-source data visualization framework. In the performance comparison results between continual learning algorithms, we found that the replay-based algorithms outperformed the regularization-based algorithms, and the experience replay (ER) algorithm had the best diagnostic accuracy. We further tuned the number and length of data samples used for a memory buffer of the ER algorithm to maximize its performance. We confirmed that the performance of the ER algorithm becomes higher when a longer data length is used. Consequently, the proposed system showed an accuracy of 98.7%, while only 16.5% of the previous data was stored in memory buffer. Our lightweight CNN model was also able to diagnose a fault type of one data sample within 3.76 ms on the Raspberry Pi 4B device.

• Journal of Animal Science and Technology
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• v.65 no.4
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• pp.720-734
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• 2023

In Korea, Korea Proven Bulls (KPN) program has been well-developed. Breeding and evaluation of cows are also an essential factor to increase earnings and genetic gain. This study aimed to evaluate the accuracy of cow breeding value by using three methods (pedigree index [PI], pedigree-based best linear unbiased prediction [PBLUP], and genomic-BLUP [GBLUP]). The reference population (n = 16,971) was used to estimate breeding values for 481 females as a test population. The accuracy of GBLUP was 0.63, 0.66, 0.62 and 0.63 for carcass weight (CWT), eye muscle area (EMA), back-fat thickness (BFT), and marbling score (MS), respectively. As for the PBLUP method, accuracy of prediction was 0.43 for CWT, 0.45 for EMA, 0.43 for MS, and 0.44 for BFT. Accuracy of PI method was the lowest (0.28 to 0.29 for carcass traits). The increase by approximate 20% in accuracy of GBLUP method than other methods could be because genomic information may explain Mendelian sampling error that pedigree information cannot detect. Bias can cause reducing accuracy of estimated breeding value (EBV) for selected animals. Regression coefficient between true breeding value (TBV) and GBLUP EBV, PBLUP EBV, and PI EBV were 0.78, 0.625, and 0.35, respectively for CWT. This showed that genomic EBV (GEBV) is less biased than PBLUP and PI EBV in this study. In addition, number of effective chromosome segments (M_e) statistic that indicates the independent loci is one of the important factors affecting the accuracy of BLUP. The correlation between M_e and the accuracy of GBLUP is related to the genetic relationship between reference and test population. The correlations between M_e and accuracy were -0.74 in CWT, -0.75 in EMA, -0.73 in MS, and -0.75 in BF, which were strongly negative. These results proved that the estimation of genetic ability using genomic data is the most effective, and the smaller the M_e, the higher the accuracy of EBV.

• Macromolecular Research
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• v.17 no.5
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• pp.319-324
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• 2009

A new $\pi$-conjugated polymer, poly[(2-methoxy-(5-(2-(4-oxyphenyl)-5-phenyl-1,3,4-oxadiazole)-hexyloxy))-1,4-pheny1ene-1,2-etheny1ene-alt-(10-hexyl-3,7-phenothiazine )-1,2-ethenylene] (PTOXDPPV), was synthesized by the Heck coupling reaction. The electron transporting unit, conjugated 1,3,4-oxadiazo1e (OXD), is attached on the main chain via linear 1,6-hexamethylenedioxy chain. The band gap and photoluminescence (PL) maximum of PTOXDPPV are 2.35 eV and 565 nm, respectively. These values are very close to those of po1y[(2,5-didecyloxy-1,4-phenylene-1,2-etheny1ene )-alt-(l0-hexyl-3,7-phenothiazine)-1,2-ethenylene] (PTPPV), which does not have OXD pendant. The estimated HOMO energy level of PTOXDPPV was -4.98 eV, which is very close to that of PTPPV (-4.91 eV). The maximum wavelength of EL device based on PTOXDPPV and PTPPV appeared at 587 and 577 nm, respectively. In the PL and EL spectrum, the emission from OXD pendant was not observed. This indicates that the energy transfer from OXD pendants to main chain is occurred completely. The EL device based on PTOXD-PPV (ITO/PEDOT/PTOXDPPV/AI) has an efficiency of 0.033 cd/A, which is significantly higher than the device based on PTPPV (ITO/PEDOT/PTPPV/AI) ($4.28{\times}10^{-3}\;cd/A$). From the results, we confirm that the OXD pendants in PTOXDPPV facilitate hole-electron recombination processes in the emissive layer effectively.

• Smart Media Journal
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• v.9 no.3
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• pp.41-45
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• 2020

Recently, artificial intelligence (AI) and the Internet of things (IoT), which are represented by machine learning and deep learning among IT technologies related to the Fourth Industrial Revolution, are applied to our real life in various fields through various researches. In this paper, IoT and AI using object recognition technology are applied to classify clothing. For this purpose, the image dataset was taken using webcam and raspberry pi, and GoogLeNet, a convolutional neural network artificial intelligence network, was applied to transfer the photographed image data. The clothing image dataset was classified into two categories (shirtwaist, trousers): 900 clean images, 900 loss images, and total 1800 images. The classification measurement results showed that the accuracy of the clean clothing image was about 97.78%. In conclusion, the study confirmed the applicability of other objects using artificial intelligence networks on the Internet of Things based platform through the measurement results and the supplementation of more image data in the future.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.3
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• pp.124-129
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• 1989

The cordierite is of great interest for microelectronic packaging. Its main advantages are low dielectric constant and low thermal expansion. The cordierite precursor obtained by sol-gel synthesis whose sintering temperature is about $900^{circ}C$ is an amorphous and cristal white powder. Green and fired cordierite samples were studied by XPS for microscopic properties. At the surface the results of XPS show forte diminution of Mg in comparison with its value at volume and the deficit of Mg compensates by augmentation of Al and Si. $pi$-cordierite phase is present near the surface $<100{\AA}$ and small quantities of magnesium aluminate ($MgAl_2O_4) is present in the bulk. Sintering of the green cordierite introduces no chemical modification at the surface.

• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.1
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• pp.49-55
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• 2019

This study proposes a robust control of a fin position servo system using the H-infinity loop-shaping method. The fin position control system has a proportional (P) position controller and a proportional-integral (PI) controller. In this work, the position control loop requires a wide bandwidth. No current control loop exists due to the compact design of the system. Hence, the controller parameters are difficult to determine using the traditional cascade design method. The $H_{\infty}$ controller design method is used to design the controller's gain to achieve good performance and robustness. First, the transfer function of the system, which can be divided into tunable and fixed parts, is derived. The tunable part includes the position P controller and speed PI controller. The fixed part includes the rest of the system. Second, the optimized controller parameters are calculated using Matlab $H_{\infty}$ controller design program. Finally, the system with optimized controller is tested by simulation and experiment. The control performance is satisfactory, and the $H_{\infty}$ controller design method is proven to be valid.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.5
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• pp.509-515
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• 2022

As the 4th industrial revolution based on ICT is progressing in the manufacturing field, interest in building smart factories that can be flexible and customized according to customer demand is increasing. To this end, it is necessary to maximize the efficiency of factory by performing an automated process in real time through a network communication between engineers and equipment to be able to link the established IT system. It is also necessary to collect and store real-time data from heterogeneous facilities and to analyze and visualize a vast amount of data to utilize necessary information. Therefore, in this study, four types of controllers such as PLC, Arduino, Raspberry Pi, and embedded system, which are generally used to build a smart factory that can connect technologies such as artificial intelligence (AI), Internet of Things (IoT), and big data, are configured. This study was conducted for the development of a program that can collect and store data in real time to visualize and manage information. For communication verification by controller, data communication was implemented and verified with the data log in the program, and 3D monitoring was implemented and verified to check the process status such as planned quantity for each controller, actual quantity, production progress, operation rate, and defect rate.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.7
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• pp.520-527
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• 2011

Recently, Influenza(AI, PI) patients have been increasing rapidly. But, there is a lack of isolation hospitals. In particular, according to increase the rate of patients with airborne infection, in order to prevent the spread of pathogens, design of layout plan and air conditioning system of isolation hospitals becomes more important to maintain patient's room as negative pressure. In this study, the spread of pathogens are analyzed as room differential pressure, moving time of medical staff and patients, and moving way in isolation hospitals by multizone simulation; CONTAM 2.4. Through the analysis, the ways to improve isolation hospital considered at the design step are reached to prevent the spread of pathogens effectively. Also, it verifies that HVAC system for isolation hospital is suitably designed as standard.

• Cross-Cultural Studies
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• v.37
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• pp.185-209
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• 2014

This paper is a study on The Korea Magzine. The magazine has a series. One of them is KOREA'S NOTED WOMEN. This is the women who are all Chinese women. They are Yo-WHA-SI(여와씨), A-WHANG, YU-YUNG(아황과 여영), T'AI-IM AND T'AI-SA(태임과 태사), WANG SO-KOON(왕소군), Su Wang Mo(서왕모), Yang Kwi-pi(양귀비), SU-SI(서시), TAK MOON-KOON(탁문군). The story of the women in the magazine were studied in a series of articles of reasons. First, it is because the Chinese women living in the hearts of Koreans. Second, the Koreans because these women want to love passionately, and be like. Third, because the Chinese women was also well-known in Korea as well known in East Asia. Was This series is used in any way. Features shown in the description was investigated. It explains how to understand what they Korea. Deliberately omitted, and were also added. I also used the analogy and comparison. This does not make sense but were accepted. Finally, we fully understand and take advantage of the literature.