• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.4
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• pp.108-116
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• 2000

Undesired trouble such as chatter vibration and burning on the ground surface appears frequently in the cylindrical plunge grinding process. Establishment of a credible fault diagnostic system for the grinding process is the major purpose of this study. Power signals generated during the grinding operation were sampled and analyzed to determine the relationship between grinding troubles and behavior of signal changes. In addition, a neural network was optimized with a momentum coefficient a learning rate, and a structure of the hidden layer through the iterative learning process. Based on the established system, success rates of the trouble recognition were verified.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.441-445
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• 2007

In this paper we demonstrated the applications of OTFTs (organic thin film transistors) to flexible displays such as AM-EPD (active matrix electrophoretic display) and AM-OLED (active matrix organic light emitting diode), and also to integrated circuits. The OTFTs using pentacene semiconductor layer and PVP gate dielectric and Au S/D electrodes exhibited good performance for AM-EPD with the mobility of $0.59\;cm^{2}/V.sec,$ and with also good uniformity over 2.5" diagonal area. However, it is nor enough for AM-OLED requiring the mobility larger than $1\;cm^{2}/V.sec$ for large area displays. The integrated circuits also worked, producing the operating frequency of 1MHz. We need to develop a fabrication process to reduce parasitic capacitance for high frequency operation.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.831-835
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• 2007

Energy Saving is one of worldwide emerging issues. These days, applicable techniques of railway vehicle's regenerative energy are investigating in worldwide railway industries. Energy saving methods are "Downsizing energy loss" and "Re-utilizing kinetic energy". Useful plans for Downsizing energy loss are "adjusting operation table" and "optimizing running pattern". Furthermore, regenerative energy that is produced with decreasing speed and stoping, is an important element with reducing vehicle's weight, raising equipment 's efficiency, decreasing running resistance and re-configurating running pattern. Sustainable energy storage mass : Flywheel, EDLC(electrical double layer capacitor) and Secondary battery are applied in overseas, but these cases are not reported within the country. This research is reported for problems and economical validity that comes from by installing sustainable regenerative energy storage system in korean railway industries.

• Journal of Chest Surgery
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• v.25 no.9
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• pp.891-899
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• 1992

Esophageal atresia with tracheoesophageal fistula may occur as separate, but usually occur in combination. First described by Thomas Gibson in 1696, esophageal atresia was not successfully treated until 1939 when the first two survivors of staged correction were described by Ladd and Leven. In 1941, Haight and Towsley performed the first successful one-stage primary repair. We report three cases of esophageal atresia with tracheoesophageal fistula of which were treated with one-stage surgical repair method. The operation was performed tra-nspleurally through right 4th intercostal space. The fistula in the trachea was closed with interrupted 5-O prolene sutures and esophagoesophageal anastomosis was performed with 3-O prolene single layer sutures in all cases. All patients tolerated the operative procedures and recovered uneventfully. On follow-up study, anastomotic stricture was developed in one patients, so esophageal dilatation was performed for it with the Griintzig balloon catheter and the result was satisfactory. The other patients were well-being without any complication.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.6
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• pp.54-66
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• 1997

The objectives of this study is to introduce and apply neural network theory to real hydrologic systems for stochastic nonlinear predicting of daily runoff discharge in the river catchment. Back propagation algorithm of neural network model is applied for the estimation of daily stochastic runoff discharge using historical daily rainfall and observed runoff discharge. For the fitness and efficiency analysis of models, the statistical analysis is carried out between observed discharge and predicted discharge in the chosen runoff periods. As the result of statistical analysis, method 3 which has much processing elements of input layer is more prominent model than other models(method 1, method 2) in this study.Therefore, on the basis of this study, further research activities are needed for the development of neural network algorithm for the flood prediction including real-time forecasting and for the optimal operation system of dams and so forth.

• 한국연소학회:학술대회논문집
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• 2000.05a
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• pp.152-161
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• 2000

The catalytically stabilized combustion of $CH_4$-air mixture on platinum catalyst was investigated numerically using a 2-D boundary layer model with detailed heterogeneous and homogeneous chemistries. The actual surface site density of monolith coated with platinum was decided by the comparison with experimental data. The comparisons were made between results for cases where only heterogeneous chemistry was allowed and both heterogeneous and homogeneous chemistries were allowed. It was found that the homogeneous reaction in the monolith had little effect on the change of temperature profile, methane conversion rate and light off location. The contributions of each reactions related with CO formation were discussed on the surface. The effects of operation conditions such as equivalence ratio, temperature, velocity and pressure at the entrance were studied. In thermal combustor, CO and NOx was produced less than 1 ppm at the exit and the production of $N_{2}O$ was more dominant than that of NO.

• Journal of Astronomy and Space Sciences
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• v.27 no.4
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• pp.407-412
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• 2010

Software reusability is one of key factors which impacts cost and schedule on a software development project. It is very crucial also in satellite simulator development since there are many commercial simulator models related to satellite and dynamics. If these models can be used in another simulator platform, great deal of confidence and cost/schedule reduction would be achieved. Simulation model portability (SMP) is maintained by European Space Agency and many models compatible with SMP/simulation model interface (SMI) are available. Korea Aerospace Research Institute (KARI) is developing hardware abstraction layer (HAL) supported satellite simulator to verify on-board software of satellite. From above reasons, KARI wants to port these SMI compatible models to the HAL supported satellite simulator. To port these SMI compatible models to the HAL supported satellite simulator, simulation scheduler is preliminary designed according to the SMI standard.

• Journal of Korean Neurosurgical Society
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• v.40 no.5
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• pp.381-383
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• 2006

Spinal extradural arachnoid cyst is uncommon and rarely cause neural compression. We report a rare case of severe cord compression due to septated spinal extradural arachnoid cyst. A 35-year-old woman has developed back pain 3 months prior to her visit, but recently motor weakness and urinary incontinence occurred. Magnetic resonance images showed an extradural cyst posterior to the cord, which was flattened and displaced from T12 to L2. Urgent decompressive laminectomy and cyst removal was performed. Histopathological examination confirmed that cyst wall was formed by nonspecific fibrous connective tissue without a single-cell layer of inner arachnoid lining. Motor weakness and voiding difficulty were recovered completely after operation.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1403-1406
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• 2007

An effective WOLED structure was demonstrated which improved a luminous efficiency and white color chromaticity independent on applied bias by employing effective carrier transporting layer, without any alteration of emissive materials. The modified WOLEDs exhibited 2 times higher luminous efficiency than the control device and showed balanced white emission during an operation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.2
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• pp.202-210
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• 1994

In this paper, the network management system is implemented based on the analysis of reguirements and network operation and management for Flexible Automation. Network management is necessary, which controls and supervises the network resources in the communication network. By means of both analytical methods and queueing model, the delay time distributions due to the increasement of transmission data are obtained and analyzed. The operations of this network management system are certified through the test environments with the network adaptor and softwares for each layer.