• The Journal of the Korea Contents Association
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• 제11권12호
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• pp.357-363
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• 2011

The aim of this study is to compare radiation dose in diagnostic X-ray radiography and calculated by different mathematical equation. The result of ESDs direct measurement and that calculated by Mori NDD-M shows the biggest difference. On the other hand, equation by Edmonds shows the lowest difference of ESDs. Also, Rectification due to the difference between direct dose measurement and calculation method commutated three-phase, single phase and inverter type, show less difference in the drive way. In conclusion, this study can be helpful for expecting radiation dose-exposure and control exposure parameters for the diagnostic x-ray radiography.

• Journal of Korean Neurosurgical Society
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• 제52권2호
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• pp.103-106
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• 2012

Objective : To prospectively assess the diagnostic and clinical value of a new technique (3-tesla magnetic resonance myelography, 3T MRM) as compared to computed tomographic discography (disco-CT) in patients with far lateral disc herniation. Methods : We evaluated 3T MRM and disco-CT of 25 patients, whom we suspected of suffering from far lateral disc herniation. Using an assessment scale, 4 observers examined independently both 3T MRM and disco-CT images. We analyzed observer agreement and the accentuation of each image. Results : We found complete matching, and observer agreement, between high resolution images of 3T MRM and disco-CT for diagnosing far lateral disc herniation. Conclusion : We think noninvasive 3T MRM is an appropriate diagnostic tool for far lateral disc herniation as compared to disco-CT.

• Journal of the Korean Society for Railway
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• 제9권4호
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• pp.357-361
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• 2006

This paper dealt with the performance evaluation and the diagnostic techniques of lightning arresters for DC electric traction vehicle. Field Measurements on the protective operation of lightning arresters against surge currents were carried out on running vehicles to acquire the data necessary for the diagnosis. The frequency and the magnitude of surge events were analyzed. Surge currents of $1\sim3$ times were recorded in one running service route and their magnitudes were ranges of $150A\sim2kA$. Also, an acceleration experiment on a lightning arrester by the standard lightning impulse current of 8/20 us and 5 kA was performed to know the aging characteristics. After the surge current application of 3,000 times, the reference voltage decreased by 4.5 %, and the leakage current was below 10 uA at the continuous operating voltage and about 50 uA at the rated voltage. From the experimental results, we propose a decision level of leakage current for the arrester used in this paper and designed an arrester tester which analyzes arrester condition by the magnitude of leakage current.

• Nuclear Engineering and Technology
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• 제38권2호
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• pp.155-162
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• 2006

It is necessary to monitor periodically the operability of safety-related motor-operated valves (MOVs) in nuclear power plants. However, acquiring diagnostic signals for MOVs is very difficult, and doing so requires an excessive amount of time, effort, and expenditure. This paper introduces an accurate and economical method to evaluate the performance of MOVs remotely. The technique to be utilized includes electrical measurements and signal processing to estimate the motor torque and the stem thrust, which have been cited as the two most effective parameters in diagnosing MOVs by the US Nuclear Regulatory Commission. The motor torque is calculated by using electrical signals, which can be measured in the motor control center (MCC). Some advantages of using the motor torque signature over other signatures are examined. The stem thrust is calculated considering the characteristics of the MOV and the estimated motor torque. The basic principle of estimating stem thrust is explained. The developed method is implemented in diagnostic equipment, namely, the Motor Operated Valve Intelligent Diagnostic System (MOVIDS), which is used to obtain the accuracy of and to validate the applicability of the developed method in nuclear power plants. Finally, the accuracy of the developed method is presented and some examples applied to field data are discussed.

• Proceedings of the KSMRM Conference
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• 대한자기공명의과학회 2003년도 제8차 학술대회 초록집
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• pp.32-32
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• 2003

The purpose of paper is to implement a PC-based software for 3D visualization of brain fiber tractography and high-resolution anatomical data 서론： DTI (Diffusion tensor imaging) is a very useful noninvasive MRI technique for providing the direction and connectivity information of brain fiber tracts. Especially in patients with glioma, fiber tracts on the lesion side in the brain had varying degrees of displacement or disruption as a result of the tumor. Tract disruption resulted from direct tumor involvement, compression on the tract, and vasogenic edema surrounding the tumor. To combine information on fiber tracts surrounding turner with a high-resolution anatomical 3D image may be clinically useful for surgical planning. Therefore we implemented a software for visualizing both brain fiber tractography and anatomical data.

• Proceedings of the KSMRM Conference
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• 대한자기공명의과학회 2003년도 제8차 학술대회 초록집
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• pp.83-83
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• 2003

Purpose： The purpose of paper is to implement a PC-based software for 3D visualization of brain fiber tractography and high-resolution anatomical data introduction： DTI (Diffusion tensor imaging) is a very useful noninvasive MRI technique for providing the direction and connectivity information of brain fiber tracts. Especially in patients with glioma, fiber tracts on the lesion side in the brain had varying degrees of displacement or disruption as a result of the tumor. Tract disruption resulted from direct tumor involvement, compression on the tract, and vasogenic edema surrounding the tumor. To combine information on fiber tracts surrounding tumor with a high-resolution anatomical 3D image may be clinically useful for surgical planning. Therefore we implemented a software for visualizing both brain fiber tractography and anatomical data.

• Transactions of the Korean Society of Mechanical Engineers
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• 제18권2호
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• pp.323-338
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• 1994

This paper outlines a framework for performing intelligent sensor validation for a diagnostic expert system while reasoning under uncertainty. The emphasis is on the algorithmic preprocess technique. A companion paper focusses on heuristic post-processing. Sensor validation plays a vital role in the ability of the overall system to correctly detemine the state of a plant monitored by imperfect sensors. Especially, several theoretical developments were made in understanding uncertain sensory data in statistical aspect. Uncertain information in sensory values is represented through probability assignments on three discrete states, "high", "normal", and "low", and additional sensor confidence measures in Algorithmic Sv.Upper and lower warning limits are generated from the historical learning sets, which represents the borderlines for heat rate degradation generated in the Algorithmic SV initiates a historic data base for better reference in future use. All the information generated in the Algorithmic SV initiate a session to differentiate the sensor fault from the process fault and to make an inference on the system performance. This framework for a diagnostic expert system with sensor validation and reasonig under uncertainty applies in HEATXPRT$^{TM}$, a data-driven on-line expert system for diagnosing heat rate degradation problems in fossil power plants.

• Pediatric Infection and Vaccine
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• 제3권2호
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• pp.207-213
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• 1996

Herpes simplex virus(HSV) infections of the CNS are associated with significant morbidity and mortality even when appropriate antiviral therapy is administered. HSV infections of the brain can be subdivided into two categories : neonatal HSV infections, which usually are caused by HSV type 2, and herpes simplex encephalitis(HSE), which occur in patients over 3 months old and is nearly uniformly caused by HSV type 1. The clinical presentation of HSE is one of the focal encephalopathic process associated with altered levels of consciousness, fever, focal seizures and hemiparesis. But because of the lack of pathognomic clinical presentation and diagnostic procedure, the efforts to develop alternative diagnostic procedure have led to the use of new diagnostic technique such as polymerase chain reaction(PCR). We report a case of HSV type 1 encephalitis in 13 month old male infant who presented with altered level of consciousness, fever and focal seizures. With the use of the PCR, HSV-1 DNA was detected in cerebrospinal fluid from the patient. The symptoms and signs of encephalitis subsided by treatment with acyclovir in 14 days.

• Korean Journal of Bronchoesophagology
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• 제17권1호
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• pp.9-13
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• 2011

Endobronchial ultrasound (EBUS), which enables visualization of lesions beyond the bronchus, broadens the fields of bronchoscopy. Two types of ultrasound, radial and linear, are used for bronchoscopy. Radial EBUS is performed by inserting an ultrasound mini-probe through the working channel of a flexible bronchoscope. Evaluation of the depth of invasion of early endobronchial lung cancers using radial EBUS is useful in deciding endobronchial treatment. A central tumor limited to within the cartilaginous layer is a good indication for endobronchial photodynamic therapy. EBUS-guide sheath (GS) technique is a sampling method assisted by localization of peripheral lesions using EBUS. The diagnostic yield of EBUS-GS method is higher than that of conventional transbronchial biopsy. High diagnostic values of EBSU-GS method are reported even in small (${\leq}2cm$) peripheral tumors. Linear EBUS is used for endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA). EBUS-TBNA has high diagnostic yields in mediastinal staging of lung cancer even in patients having radiologically early stage lung cancers with normal CT or PET findings in the mediastinum. EBUS is a valuable method in evaluating early endobronchial tumors and peripheral small lung cancers and as well as in mediastinal staging.

• The Journal of the Korean dental association
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• 제49권3호
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• pp.146-152
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• 2011

Historically, the screening of patients for signs of oral cancer and precancerous lesions has relied upon the conventional oral examination. A variety of commercial diagnostic aids and adjunctive techniques are developed to potentially assist in the screening of healthy patients for evidence of occult cancerous change. This paper is reviewing the literature associated with current oral cancer screening aids such as spectroscopy, chemoiluminescence, exfoliative cytopathology, vital staining and saliva as a diagnostic tool. Despite the increased public awareness of oral cancer, no technique or technology to date has provided definitive evidence to suggest that it improves the sensitivity or specificity of oral cancer screening beyond clinical oral examination alone.