• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.949-950
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• 2007

Before applying HTS power device to the real utility system, a system analysis should be carried out by some simulator. PSCAD/EMTDC simulation tool is one of the most popular system analysis. Unfortunately the model component for HTS coil is not provided in the PSCAD/EMTDC simulation tool. In this paper, the model component for the HTS coil has been developed considering the real field data, temperature and magnetic field, of the HTS coil. The numerical model of HTS coil in PSCAD/EMTDC was designed by using the real experimented data obtained from the $AMSC^{TM}$ wire characteristic. The developed model component for HTS coil could be variously used when the power system includes HTS coil.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.6
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• pp.106-112
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• 2019

Rotary swaging is a method of forging automotive drive shafts. In this paper, we propose a new two-hammer forging technique by applying the problem-solving approach TRIZ to improve the efficiency and productivity of the rotary swaging automation process. We will simplify the materials and hammers via the 3D modeling tool SolidWorks for high accuracy of a comparative analysis of existing and proposed methods under the same boundary conditions. In addition, we will compare the stress trends of the proposed model using ANSYS Workbench and verify the feasibility through a comparison of the simulation results using DEFORM. Relative to the existing method, the proposed method can decrease production costs and improve efficiency of the automation process by reducing the power source.

• Clinical Pain
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• v.19 no.2
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• pp.138-141
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• 2020

Clay-shoveler's fractures are rare stress-type avulsion fractures of the spinous processes especially in sports. There have been two case reports that discussed clay-shoveler's fractures in golf. A 36-year-old beginner golfer presented with a pain in the back after practicing golf swing. No fractures were detected using cervical radiography; however, computed tomography (CT) and magnetic resonance imaging (MRI) revealed T2~T3 spinous process fractures. The patient was treated conservatively and his pain subsided. The mechanism of injury is speculated to that of clay-shoveler's fractures. Therefore, if a golfer suffers persistent pain in the cervicothoracic region, clay-shoveler's fracture is one possibility to consider.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.3
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• pp.36-42
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• 2022

Whereas the necessity for recycling and reuse is being emphasized owing to the depletion of resources and waste disposal problems caused by the continuous development of the industry, the importance of remanufacturing has been highlighted recently. Re-manufacturing involves a series of processes in which failed disposal or aging goods are recovered to a state similar to that of a new product. In this regard, machine tools, which are large structures, can achieve the effect of remanufacturing. Among the various elements constituting the machine tool, the main spindle portion that affects the processing precision is critical. Therefore, this study is conducted to derive improvement measures for the main axis of an old Miller planner via reverse engineering and central composite design, which is one of the core processes of remanufacturing.

• Journal of Ceramic Processing Research
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• v.13 no.spc2
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• pp.394-397
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• 2012

In this work, we studied the influence of the dopant elements concentration on the properties of SnO2 thin films deposited by pulsed laser deposition. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Hall effect measurement and UV-Vis studies were performed to characterize the deposited films. XRD results showed that the films had polycrystalline nature with tetragonal rutile structure. FE-SEM micrographs revealed that the as deposited films composed of dense microstructures with uniform grain size distribution. All the films show n-type conduction and the best transparent conductive oxide (TCO) performance was obtained on 6 wt% Sb2O5 doped SnO2 film prepared at pO2 of 60mtorr and Ts of 500 ℃. Its resitivity, optical transmittance, figure of merit are 7.8 × 10-4 Ω cm, 85% and 1.2 × 10-2 Ω-1, respectively.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.2_2
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• pp.415-424
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• 2024

This study analyzes trends and characteristics of the machine tool remanufacturing industry and proposes a standard process that considers environmental impact assessment during the remanufacturing process. First, trends in remanufacturing and environmental regulations are reviewed. And the current status of the machine tool remanufacturing industry and cases of national R&D projects related to machine tools are analyzed. Machine tool remanufacturing has a high resource saving effect, and remanufacturing is carried out as a finished product rather than as a part. And the scope of remanufacturing work is very wide due to the performance improvement of the machine and the addition of features. In order for the machine tool remanufacturing industry to be competitive, it is necessary to create products with high added value. In addition, in order to respond to international environmental regulations, it is necessary to secure related data by conducting an environmental impact assessment together during remanufacturing.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1726-1728
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• 1999

Dielectric and piezoelectric properties of xPb$(Al_{1/2}Ta_{1/2})O_3$-(1-x)Pb$(Zro_{0.52}Ti_{0.48})O_3$ system were investigated. The highest density of $7.80g/cm^3$ for PAT-PZT ceramics of 5mol% PAT was obtained. The relative permittivity of PAT-PZT ceramics of 5mol% PAT was 1.642 at room temperature. The maximum value of electromechanical coupling factor $k_p$ of 55% and $k_t$ of 33% were obtained at the composition of 5mol% PAT. The grain sizes were reduced by increasing the amount of PAT, however mechanical quality factor$(Q_m)$ had a minimum value of 44 at the composition of 5mol% PAT.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.722-725
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• 2012

In this paper, we design an 8-bit eSuse OTP (one-time programmable) memory based on a $0.35{\mu}m$ BCD process using differential paired eFuse cells which can sense BL data without a reference voltage and also have smaller sensing resistances of programmed eFuse links. The channel widths of a program transistor of the differential eFuse OTP cell are splitted into $45{\mu}m$ and $120{\mu}m$. Also, we implement a sensing margin test circuit with variable pull-up loads in consideration of variations of the programmed eFuse resistances. It is confirmed by measurement results that the designed 8-bit eFuse OTP memory IP gives a better yield when the channel width is $120{\mu}m$.

• Tuberculosis and Respiratory Diseases
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• v.72 no.2
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• pp.228-231
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• 2012

Bronchobiliary fistula (BBF), defined as an abnormal communication between the biliary duct and bronchial trees, is a very rare condition. Bilioptysis is a pathognomonic finding for BBF. We studied a 58-year-old man, who had a BBF complicated by liver biloma that occurred after radiofrequency ablation. The diagnosis was confirmed by the presence of bile-stained sputum and an Endoscopic Retrograde Cholangio-Pancreatography. BBF was treated successfully by endoscopic sphincterotomy and biliary drainage with insertion of a double pig-tail plastic stent into the biloma. We suggest that the optimal choice of treatment modality for BBF depends on the natural course of the underlying disease, and the status of the biliary stricture.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.9
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• pp.107-115
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• 2020

The rotation accuracy of the main spindle that determines the accuracy of CNC machine tools is closely related to the quality of production because it directly affects the shape error and surface roughness of the workpiece. Therefore, the main spindle requires high rotation accuracy, rigidity, and rotation technology. This rotation accuracy is greatly affected by the bearing, center alignment between rotating parts, assembly tolerance, and unbalance of the rotation mass. In this study, the effects of the unbalance of the rotation mass of the main spindle on the rotation accuracy were investigated experimentally. In particular, we tried to study the technical reasons for improving the unbalance of the main spindle and maintaining the rotation accuracy as we verified the correlation between the vibration characteristics of CNC machine tools due to the specifically set unbalance amount and the surface roughness of the workpiece.