• The Transactions of the Korean Institute of Electrical Engineers P
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• v.51 no.1
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• pp.52-54
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• 2002

This research presented in this paper focuses on a system development for checking stator's wedge of large generator in heavy industry. The system is composed of impactor, A/D converter and digital signal processing board. Also this paper proposes a method for detection of stator's insulating state using analysis algorithm. As developed impact system is acting, impact wave is generated real time and transferred data to microprocessor. Using communication program this signal move microprocessor to hard directory of note book with 1000 data/sec. The developed system and analysis program performed very well by real stator's wedge in large generator.

• Journal of information and communication convergence engineering
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• v.21 no.1
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• pp.24-31
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• 2023

The solid-state drive (SSD) possesses higher input and output speeds, more resistance to physical shock, and lower latency compared with regular hard disks; hence, it is an increasingly popular storage device. However, tiny components on an internal printed circuit board (PCB) hinder the manual detection of malfunctioning components. With the rapid development of artificial intelligence technologies, automatic detection of components through convolutional neural networks (CNN) can provide a sound solution for this area. This study proposes applying the YOLOv5 model to SSD PCB component detection, which is the first step in detecting defective components. It achieves pioneering state-of-the-art results on the SSD PCB dataset. Contrast experiments are conducted with YOLOX, a neck-and-neck model with YOLOv5; evidently, YOLOv5 obtains an mAP@0.5 of 99.0%, essentially outperforming YOLOX. These experiments prove that the YOLOv5 model is effective for tiny object detection and can be used to study the second step of detecting defective components in the future.

• Journal of Broadcast Engineering
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• v.25 no.2
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• pp.200-207
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• 2020

Recently, deep neural networks such as CNN are showing excellent performance in various fields such as image classification, object recognition, visual quality enhancement, etc. However, as the model size and computational complexity of deep learning models for most applications increases, it is hard to apply neural networks to IoT and mobile environments. Therefore, neural network compression algorithms for reducing the model size while keeping the performance have been being studied. In this paper, we apply few compression methods to CNN models and evaluate their performances in the embedded environment. For evaluate the performance, the classification performance and inference time of the original CNN models and the compressed CNN models on the image inputted by the camera are evaluated in the embedded board equipped with QCS605, which is a customized AI chip. In this paper, a few CNN models of MobileNetV2, ResNet50, and VGG-16 are compressed by applying the methods of pruning and matrix decomposition. The experimental results show that the compressed models give not only the model size reduction of 1.3~11.2 times at a classification performance loss of less than 2% compared to the original model, but also the inference time reduction of 1.2~2.21 times, and the memory reduction of 1.2~3.8 times in the embedded board.

• KIPS Transactions on Software and Data Engineering
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• v.4 no.2
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• pp.65-70
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• 2015

In the PCB(Printed Circuit Board) manufacturing industry, the yield is an important management factor because it affects the product cost and quality significantly. In real situation, it is very hard to ensure a high yield in a manufacturing shop because products called chips are made through hundreds of nano-scale manufacturing processes. Therefore, in order to improve the yield, it is necessary to analyze main fault process and equipment that cause low PCB yield. This paper proposes a systematic approach to discover fault-causing processes and equipment by using a logistic regression and a stepwise variable selection procedure. We tested our approach with lot trace records of real work-site. A lot trace record consists of the equipment sequence that the lot passed through and the number of faults for each fault type in the lot. We demonstrated that the test results reflected the real situation of a PCB manufacturing line.

• Archives of Reconstructive Microsurgery
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• v.16 no.2
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• pp.133-143
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• 2007

For the better success in the society, it is important to collect opinions from members. The progress was slow before because it was hard to collect the opinions from each member. But since we have opened the web site it gets easier to evolve with the society for microsurgery, and expect to have active participations from the members. We make 20 questions in three different groups. The researches are made on participation, development in science council that starting from 2005 October to 2007 June, education on training with member's preference to thesis and individuality and suggestion. Thus we have results following to that research. 1.75% of the members vote for the lecture has to be substantial, and also want the atmosphere of the council to be more sincere. 46.2% of members want the council to be not only exchange information but also the place to experience the social intercourse. 2. When the thesis is present and submitted that will also connect to main society. It will be counted as equal as board thesis, only if the thesis can count in both plastic & reconstructive surgery and orthopedic surgery. Then it will be scored as same as examination of board, and will be a receipt of paper by home page 3. The information-oriented project on our council is slower than what members expected. 100% of members voted yes to online thesis examination, and 66.7% of members voted for preference of web site. We need to make improvements on our web pages as soon as possible such as online payment with credit card. 4. According to the result of questionnaire, our web site helps member's participation in council and eventually become a bridge between members. We hope the questionnaires would help us to develop the council and eventually would help us to society with each other in the council. We also hope this council would be the one that connect all of us in society.

• Journal of IKEEE
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• v.20 no.1
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• pp.89-93
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• 2016

In this paper, we proposed SIMT based Image Signal Processor which can apply various image preprocessing algorithms and allow parallel processing of application programs such as image recognition. Conventional ISP has the hard-wired image enhancement algorithm of which the processing speed is fast, but there was difficult to optimize performance depending on various image processing algorithms. The proposed ISP improved the processing time applying SIMT architecture and processed a variety of image processing algorithms as an instruction based processor. We used Xilinx Virtex-7 board and the processing time compared to cell multicore processor, ARM Cortex-A9, ARM Cortex-A15 was reduced by about 71 percent, 63 percent and 33 percent, respectively.

• Publications of The Korean Astronomical Society
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• v.32 no.1
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• pp.197-199
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• 2017

Using the InfraRed Camera (IRC) on board the infrared astronomical satellite AKARI we study the ${3.3{\mu}m}$ polycyclic aromatic hydrocarbon (PAH) feature and its connection to active galactic nucleus (AGN) properties for a sample of 54 hard X-ray selected bright AGN, including both Seyfert 1 and Seyfert 2 type objects. The sample is selected from the 9-month Swift/BAT survey in the 14-195 keV band and all of the sources have known neutral hydrogen column densities ($N_H$). The ${3.3{\mu}m}$ PAH luminosity ($L_{3.3{\mu}m}$) is used as a proxy for star-formation (SF) activity and hard X-ray luminosity ($L_{14-195keV}$) as an indicator of the AGN power. We explore for possible difference of SF activity between type 1 (un-absorbed) and type 2 (absorbed) AGN. We use several statistical analyses taking the upper-limits of the PAH lines into account utilizing survival analysis methods. The results of our log($L_{14-195keV}$) versus log($L_{3.3{\mu}m}$) regression shows a positive correlation and the slope for the type 1/unobscured AGN is steeper than that of type 2/obscured AGN at a $3{\sigma}$ level. Also our analysis shows that the circum-nuclear SF is more enhanced in type 2/absorbed AGN than type 1/un-absorbed AGN for low $L_{14-195keV}$ luminosity/low Eddington ratio AGN, while there is no significant dependence of SF activity on the AGN type in the high $L_{14-195keV}$ luminosities/Eddington ratios.

• Journal of Conservation Science
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• v.34 no.5
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• pp.359-368
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• 2018

The purpose of this study was to analyze the wood species of the stern plank and persimmon seed from Daebudo shipwreck No.2 excavated from Daebudo, Danwon-gu, Ansan-si, and Gyeonggi-do by wiggle-matching of radiocarbon measurements. Results of the analysis showed that all the wooden boards of the hull were made from Pinus Hard Pine Group. The other parts of hull and wooden pegs were made from Pinus Hard Pine Group, Castanea spp., Quercus spp. sect. Lepidobalanus, Alnus spp., and Zelkova serrata Makino. Excavated wide-tooth wooden comb and fine-tooth bamboo comb were made from Acer spp. and Bambusoideae. Excavated rope was made from Pueraria thunbergiana Benth. The stern plank, wooden support, and persimmon stone showed ${\pm}2{\sigma}$ radiocarbon date(95.4% confidence interval) of AD 1151-1224. This indicated that the Daebudo shipwreck No.2 occurred during the early or middle 12-13th century. Our radiocarbon dating results confirmed the date speculated by archeologists based on the ceramic style.

• Korean journal of communication and information
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• v.16
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• pp.207-254
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• 2001

This study is focused on forecasting the future of tole-democracy. Many Scholars expect that internet provides technological space needing realizing the tole-democracy or deliberate democracy. Especially in Korea, this expectation is higher than other nations because of political corruption and inefficiency. Therefore internet is intended to considering as new technologies reforming political process. In 16th the general election period, many candidates established home page and used as election campaign tool. And a little of home pages is payed attention to among voters. In spite of using internet as political medium, many political communication researchers have a doubt that internet will realize ideal direct democracy. It's reason is that internet is open and anonymous space. At anonymous space, communication participators is tended to be irresponsible and non-serious. Therefore it is hard that cyber-politics will be ideal type of democracy. In this context, this paper analyzed how pauicipators communicate with others at cyber bulletin board establishing candidate's home pages. Main research questions is how do discussions at cyberspace fulfill the conditions of deliberate democracy. Therefore, concrete questions include; who are participators at candidate's cyber bulletin board; which pattern do they communicate; what is the theme of communication; which effects do the anonymous character of cyberspace influence. To that purpose, this study conducted content analysis on 4,210 written matters at 82 cyber bulletin boards of candidate's home page establishing during 16th the general election period. It can be found that cyberspace in Korea still is not deliberate democracy space and not will be. Firstly, discussion patterns at cyber bulletin board is "candidate with supporters communication space. To be exact, it is said that candidate's home page is "the space of self-convincing among supporters." Secondly, the main themes of discussion are simple emotional expressions; "I support you!" "fighting" "Be vigor" etc. By contrast, real political contents'-central or local political matters - is relatively few. In the mode of expression, real political messages are more positive, logical than simple expressions, candidates private matters. Especially this characteristic will make cyberspace as "mutual slander space" consolidating anonymous characteristic of cyberspace. finally, Cyberspace in Korea still is not real "public sphere" realizing deliberate process. Therefore to be real public sphere, it is needed to participant's ethical maturity and political citizenship. In conclusion, it is difficult that cyberspace will reconstruct the Athene's Agora. On the contrary, Cyberagora will like to be irrespectable area fulfilling the sweeping. Making the deliberate space, technological possibility and ethical condition will have to be balanced together.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1295-1299
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• 2003

The Mass Flow Controller(MFC) has become crucial in semiconductor manufacturing equipments. It is an important element because the quality and the yield of a semiconductor process are decided by the accurate flow control of gas. Therefore, the demand for the high speed and the highly accurate control of MFCs has been requested. It is hard to find an article of the control algorithm applied to MFCs. But, it is known that commercially available MFCs have PID control algorithms. Particularly, when the system detects the flow by way of heat transfer, MFC control problem contains the time delay and the nonlinearity. In this presentation, MFC control algorithm with the superior performance to the conventional PID algorithm is discussed and the superiority is demonstrated through the experiment. Fuzzy controller was utilized in order to compensate the nonlinearity and the time delay, and the performance is compared with that of a product currently available in the market. The control system, in this presentation, consists of a personal computer, the data acquisition board and the control algorithm carried out by LabWindows/CVI program on the PC. In addition, the method of estimating an actual flow from sensor output containing the time delay and the nonlinearity is presented. In conclusion, according to the result of the experiment, the proposed algorithm shows better accuracy and is faster than the conventional controller.