• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.147-150
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• 1999

A T-shaped microstripline-fed printed slot array antenna having wide bandwidth, high gain, and narrow bandwidth is presented in this paper. The proposed antenna is analyzed by using the transmission line model method. We fabricated 4$\times$1 microstrip slot array antenna and measured its return loss and radiation pattern. The maximum bandwidth of this array antenna is from 1.43 ㎓ to 2.60 ㎓, which is 58.1% for the VSWR $\leq$ 2.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.28B no.10
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• pp.783-789
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• 1991

A learing method for the recognition of printed Chinese character by using the input driven multi-layer perceptron model was proposed and the circuit representing the learning result was designed. In learning the extracted features from Chinese characters are used as inputs and the synapse's weight is integer value. So it is possible to implement the learning result with CMOS circuit.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.12
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• pp.3329-3343
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• 1995

The interaction of mixed convection and surface radiation in a printed circuit board(PCB) is investigated numerically. The electronic equipment is modeled by a two-dimensional channel with three hot blocks. In order to calculate the turbulent flow characteristics, the low Reynolds number k-.epsilon. model which is proposed by Launder and Sharma is applied. The S-4 approximation is used to solve the radiative transfer equation. The effects of the Reynolds number and geometric configuration variation of PCB on the flow and heat transfer characteristics are analyzed. As the results of this study, it is found that the thermal boundary layer occured at adiabatic wall in case with thermal radiation included, and the effect of radiation is also found to be insignificant for high Reynolds numbers. It is found, as well, that the heat transfer increases as the Reynolds number and block space increase and the channel height decreases and the heat transfer of vertical channel is greater than that of horizontal channel.

• Journal of the Korean Society for information Management
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• v.22 no.4 s.58
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• pp.61-78
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• 2005

This study investigates the influences of the service qualify of public libraries, including printed publications, internet and electronic materials, culture programs and. service, library environment and facilities, and library staff, on the general satisfaction of the users, complaining intentions, and loyalty including reuse intentions. It develops a library user satisfaction model and testifies it through path analysis using questionnaires from 443 public library users in Daegu Metropolitan City area. This study shows that service qualities of printed publications, culture programs and service, library environment and facilities, and library staff Influence significantly on the general satisfaction of the users, and that service quality of library environment and facilities is the major variable which influences satisfaction and loyalty of the public library.

• The Journal of the Korea Contents Association
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• v.17 no.7
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• pp.182-192
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• 2017

Recently, there is an increasing interest in analysis of big data that is coming from manufacturing industry. In this paper, we use PCB (Printed Circuit Board) manufacturing data to provide manufacturers with information on areas with high PCB defect rates, and to visualize them to facilitate production and quality control. We use the K-means and DBSCAN clustering algorithms to derive the high fraction of PCB defects, and compare which of the two algorithms provides more accurate results. Finally, we develop a system of MVC structure to visualize the information about bad clusters obtained through clustering, and visualize the defected areas on actual PCB images.

• Korean Journal of Oriental Medicine
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• v.10 no.1
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• pp.31-48
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• 2004

${\ulcorner}$Uirimchwaryo(醫林撮要)${\lrcorner}$ is a medical book that takes a model of written in the middle of Chosun dynasty. In the contents side, it seems to unite a korea medicine with the Geum-Won Dynasty(金元時代) in ancient china. we can think much of the value that it combines theory with experience, choosing the merits of ${\ulcorner}$Uibangyuchwi(醫方類聚)${\lrcorner}$ which were the masterpieces of the first half of Chosun Dynasty and it increased a practical use to choose easily prescription in the clinic. This book which was proofread and published by imperial physician Yang Yaesoo(楊禮壽, ? ${\sim}$ 1597) is not exist. In this condition, existing print type is added by scholars only after ${\ulcorner}$Donguibogam(東醫寶鑑)${\lrcorner}$ was compiled. When the academic conference was held in last year, I introduced a chosun printed book in japan's possession, moreover I survey more documents. I will investigate and arrange a few old printed books that are handed down to Chosun and Japan. In addition, I will present Korea and foreign researching results, trend about ${\ulcorner}$Uirimchwaryo${\lrcorner}$ which is finished lately and researching materials about translating into current korean language. We can evaluate the value and effect of ${\ulcorner}$Uirimchwaryo${\lrcorner}$ in Chosun dynasty of medical history.

• The Journal of Korean Medical History
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• v.17 no.2
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• pp.27-43
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• 2004

"Uirimchwaryo(醫林撮要)" is a medical book that takes a model of written in the middle of Chosun dynasty. In the contents side, it seems to unite a korea medicine with the Geum-Won Dynasty(金元時代) in ancient china. we can think much of the value that it combines theory with experience, choosing the merits of "Uibangyuchwi(醫方類聚)" which were the masterpieces of the first half of Chosun Dynasty and it increased a practical use to choose easily prescription in the clinic. This book which was proofread and published by imperial physician Yang Yaesoo(楊禮壽, ? ~ 1597) is not exist. In this condition, existing print type is added by scholars only after "Donguibogam(東醫寶鑑)" was compiled. When the academic conference was held in last year, I introduced a new founded book in japan's possession that printed in Chosun dynasty. Moreover I survey more documents and investigate a few old printed books that are handed down to Chosun and Japan. In addition, I will present that had done interchanges between the ancient nations in par-eastern asia, especially to have done by diplomatic mission. We can evaluate the value and effect of "Uirimchwaryo" in Chosun dynasty of medical history.

• The Transactions of the Korea Information Processing Society
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• v.4 no.7
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• pp.1881-1892
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• 1997

This paper proposes the method for recognition of printed chinese characters by probabilistic VQ networks and multi-stage recognizer has hierarchical structure. We use modular neural networks, because it is difficult to construct a large-scale neural network. Problems in this procedure are replaced by probabilistic neural network model. And, Confused Characters which have significant ratio of miss-classification are reclassified using the entropy theory. The experimental object consists of 4,619 chinese characters within the KSC5601 code except the same shape but different code. We have 99.33% recognition rate to the training data, and 92.83% to the test data. And, the recognition speed of system is 4-5 characters per second. Then, these results demonstrate the usefulness of our work.

• Journal of Technologic Dentistry
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• v.43 no.3
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• pp.84-92
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• 2021

Purpose: The purpose of this study was to compare the dimension safety evaluation between a general ultrasonic cleaner and an ultrasonic cleaner equipped with UV-C (ultraviolet-C). Methods: An edentulous model was prepared. A denture base and an occlusal rim were fabricated, and scanning was performed. After scanning, a denture base and full arch artificial teeth were designed. The full arch artificial teeth were printed using a three-dimensional printer (n=10). The residual resin was washed with alcohol and then scanned (reference data). The printed specimens were classified and cleaned using a general ultrasonic cleaner (GU group) and an ultrasonic cleaner equipped with UV-C (UC group). After each washing, a rescan was performed (scan data). Reference data and scan data were superimposed using overlapping software. Data were statistically analyzed using the Mann-Whitney test (α=0.05). Results: In the deviation values of full arch artificial teeth, the GU group showed a high deviation of 18.02 ㎛ and the UC group showed a low deviation of 15.02 ㎛. The two groups demonstrated a statistically significant difference (p<0.05). Conclusion: Full arch artificial teeth prepared using photopolymerized resin were deformed according to the temperature of water generated in the ultrasonic cleaner. It is judged that there is no deformation according to the UV-C ultrasonic cleaner.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.1085-1097
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• 2022

A printed circuit steam generator (PCSG) is being considered as the component for pressurized water reactor (PWR) type small modular reactor (SMR) that can further reduce the physical size of the system. Since a steam generator in many PWR-type SMR generates superheated steam, it is expected that dryout front oscillation can potentially cause thermal fatigue failure due to cyclic thermal stresses induced by the transition in boiling regimes between convective evaporation and film boiling. To investigate the fatigue issue of a PCSG, a reference PCSG is designed in this study first using an in-house PCSG design tool. For the stress analysis, a finite element method analysis model is developed to obtain the temperature and stress fields of the designed PCSG. Fatigue estimation is performed based on ASME Boiler and pressure vessel code to identify the major parameters influencing the fatigue life time originating from the dryout front oscillation. As a result of this study, the limit on the temperature difference between the hot side and cold side fluids is obtained. Moreover, it is found that the heat transfer coefficient of convective evaporation and film boiling regimes play an essential role in the fatigue life cycle as well as the temperature difference.