• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1810-1812
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• 2002

This test was performed to assess the insulation deterioration condition of the stator winding of Chung-Ju hydrogenerator #4 and Dae-Cheong hydrogenerator #2 which had been in service after being constructed 1980. The insulation diagnostic tests include resistance polarization index(P.I.) AC current, dissipation factor(Tan ${\delta}$) and partial discharges ($Q_{max}$). The results of diagnostic tests were compared to factory test measurements.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1330-1332
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• 2000

In general, the expected life of power semiconductor elements is known for semi-permanent, but actual characteristics are changed according to the such environment conditions obviously because of using time or operating condition. Specially, in case of using at the power plant it is very important to sustain reliability for power semiconductor which it affect to stop operating condition as deterioration or break. Therefore, we need to apply maintenance technics to got the reliability which is a prediction method of life cycle. This paper shows the result of the analyzed data for element characteristic and effects used practically and we had developed the effective equipment which for diagnostic the semiconductor performance.

• Tuberculosis and Respiratory Diseases
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• v.78 no.2
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• pp.47-55
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• 2015

Extrapulmonary tuberculosis (EPTB) constitutes about 20% of all cases of tuberculosis (TB) in Korea. Diagnosing EPTB remains challenging because clinical samples obtained from relatively inaccessible sites may be paucibacillary, thus decreasing the sensitivity of diagnostic tests. Whenever practical, every effort should be made to obtain appropriate specimens for both mycobacteriologic and histopathologic examinations. The measurement of biochemical markers in TB-affected serosal fluids (adenosine deaminase or gamma interferon) and molecular biology techniques such as polymerase chain reaction may be useful adjuncts in the diagnosis of EPTB. Although the disease usually responds to standard anti-TB drug therapy, the ideal regimen and duration of treatment have not yet been established. A paradoxical response frequently occurs during anti-TB therapy. It should be distinguished from other causes of clinical deterioration. Surgery is required mainly to obtain valid diagnostic specimens and to manage complications. Because smear microscopy or culture is not available to monitor patients with EPTB, clinical monitoring is the usual way to assess the response to treatment.

• Proceedings of the KIEE Conference
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• summer
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• pp.1124-1126
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• 2004

The measurements were performed to assess the insulation deterioration condition of the stator winding of Dae-Cheong hydro-generator ${\sharp}2$ which had been in service after being constructed 1980. After repair of the stator winding insulation. we conducted insulation diagnostic tests which include resistance, polarization index(P. I). AC current, dissipation factor($Tan{\delta}$) and partial discharges ($Q_{max}$). The results of diagnostic tests were compared to the previous records. On the basis of these test results. this paper tried to present the importance of insulation repair for the generator stator winding.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2118-2122
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• 2005

This test was performed to assess the corelation of insulation deterioration condition with breakdown voltage of the stator winding of 3.3kV class induction motors which have been in service for 10 years after being installed in 1993. The insulation diagnostic tests include resistance, polarization index(P.I), dissipation factor$({\Delta}tan{\delta})$, maximum partial discharges (Qmax) and AC breakdown test. we evaluated the corelation of insulation diagnostic test with AC breakdown test for stator wilding of high voltage induction motor.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.783-785
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• 2003

This test was performed to assess the insulation deterioration condition of the stator winding of 3.3kV class induction motors which have been in service for 15 years after being installed in 1988. The insulation diagnostic tests include resistance, polarization index(P.I). dissipation factor(${\Delta}tan{\delta}$) and maximum partial discharges(Qmax). The results of diagnostic tests were compared to the visual inspection in overhaul.

• Proceedings of the KIEE Conference
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• 2004.05b
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• pp.39-41
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• 2004

The measurements were performed to assess the insulation deterioration condition of the stator winding of Dae-Cheong hydro-generator #2 which had been in service after being constructed 1980. After repair of the stator winding insulation, we conducted insulation diagnostic tests which include resistance, polarization index(P.I), AC current, dissipation factor($Tan\delta$) and partial discharges ($Q_{max}$). The results of diagnostic tests were compared to the previous records. On the basis of these test results, this paper tried to present the importance of insulation repair for the generator stator winding.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.493-495
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• 2003

The establishment of the investigation and the maintenance technique is required for preservation of old structures in Japan. This study attempts to diagnose the deterioration status of the historic structures using the thermal infrared camera. In some structures, the difference of the spatio-temporal change was observed in the surface temperature. For example, the cold joint of concrete was examined using this method effectively. As a result of this study, we have found useful guidelines in developing methodology to conduct diagnosis of historic buildings by using thermal infrared camera.

• Proceedings of the KIEE Conference
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• 2006.07e
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• pp.51-52
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• 2006

Our company(KOWACO) has periodically performed off-line diagnostic test for 14 hydro generators (rated 11 kV over) for 15 years. In this paper, we summarized results of dissipation factor tip-up test and partial discharge test about these generators. Among these, we chose two generators and performed insulation reinforcement (cleaning and varnish painting). We compared change of insulation condition for the stator winding based upon off-line diagnostic test result before and after repair. Test result shows that insulation condition was improved after insulation reinforcement. This insulation reinforcement has a function to reduce cause of deterioration, so we can know that it extends lifetime of generator and it is a very important factor for stable operation of facilities.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.680-687
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• 2009

Several kinds of Electrical Wires have been used in Electric Multiple Units(EMU) for the supply of electric power, supervision, and the propagation of control signals. These Electrical Wires must be inspected for safe and stable operation of EMU. The degradation diagnosis to estimate the integrity of Electrical Wires has recently been requested according to the long use of EMU. This paper describes on application of diagnosis method for EMU.