• 대한방사선협회지
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• 제27권2호
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• pp.86-94
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• 2001

I. Purpose : There are many kinds of MRI techniques and there have been new techniques spreading clinically with the development of software. Clinical diagnosis value has been comparatively studied by conducting the techniques of SE, TSE, and TGSE on the

• Nuclear Engineering and Technology
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• 제46권6호
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• pp.725-736
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• 2014

It is very important to detect and identify small anomalies and component failures for the safe operation of complex and large-scale artifacts such as nuclear power plants. Each diagnostic technique has its own advantages and limitations. These facts inspire us not only to enhance the capability of diagnostic techniques but also to integrate the results of diagnostic subsystems in order to obtain more accurate diagnostic results. The article describes the outline of four diagnostic techniques developed for the condition monitoring of the fast breeder reactor "Monju". The techniques are (1) estimation technique of important state variables based on a physical model of the component, (2) a state identification technique by non-linear discrimination function applying SVM (Support Vector Machine), (3) a diagnostic technique applying WT (Wavelet Transformation) to detect changes in the characteristics of measurement signals, and (4) a state identification technique effectively using past cases. In addition, a hybrid diagnostic system in which a final diagnostic result is given by integrating the results from subsystems is introduced, where two sets of values called confidence values and trust values are used. A technique to determine the trust value is investigated under the condition that the confidence value is determined by each subsystem.

• Investigative Magnetic Resonance Imaging
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• 제25권4호
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• pp.218-228
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• 2021

Due to their high degree of freedom to transfer and acquire light, fiber optics can be used in the presence of strong magnetic fields. Hence, optical sensing and imaging based on fiber optics can be integrated with magnetic resonance imaging (MRI) diagnostic systems to acquire valuable information on biological tissues and organs based on a magnetic field. In this article, we explored the combination of MRI and optical sensing/imaging techniques by classifying them into the following topics: 1) functional near-infrared spectroscopy with functional MRI for brain studies and brain disease diagnoses, 2) integration of fiber-optic molecular imaging and optogenetic stimulation with MRI, and 3) optical therapeutic applications with an MRI guidance system. Through these investigations, we believe that a combination of MRI and optical sensing/imaging techniques can be employed as both research methods for multidisciplinary studies and clinical diagnostic/therapeutic devices.

• Imaging Science in Dentistry
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• 제44권1호
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• pp.31-35
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• 2014

Purpose: This study was performed to investigate the effect of image enhancement of periapical radiographs according to the diagnostic task. Materials and Methods: Eighty digital intraoral radiographs were obtained from patients and classified into four groups according to the diagnostic tasks of dental caries, periodontal diseases, periapical lesions, and endodontic files. All images were enhanced differently by using five processing techniques. Three radiologists blindly compared the subjective image quality of the original images and the processed images using a 5-point scale. Results: There were significant differences between the image quality of the processed images and that of the original images (P< 0.01) in all the diagnostic task groups. Processing techniques showed significantly different efficacy according to the diagnostic task (P< 0.01). Conclusion: Image enhancement affects the image quality differently depending on the diagnostic task. And the use of optimal parameters is important for each diagnostic task.

• 전자통신동향분석
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• 제39권4호
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• pp.54-62
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• 2024

The emergence and resurgence of novel respiratory infectious diseases since the turn of the millennium, including SARS, H1N1 flu, MERS, and COVID-19, have posed a significant global health threat. Efforts to combat these threats have involved various approaches, however, continued research and development are crucial to prepare for the possibility of emerging viruses and viral variants. Direct detection methods for viral pathogens include molecular diagnostic techniques and immunodiagnostic methods, while indirect diagnostic methods involve detecting changes in the condition of infected patients through imaging diagnostics, gas analysis, and biosignal measurement. Molecular diagnostic techniques, utilizing advanced technologies such as gene editing, are being developed to enable faster detection than traditional PCR methods, and research is underway to improve the efficiency of diagnostic devices. Diagnostic technologies for infectious diseases continue to evolve, and several key trends are expected to emerge in the future. Automation will facilitate widespread adoption of rapid and accurate diagnostics, portable diagnostic devices will enable immediate on-site diagnosis by healthcare professionals, and advancements in AI-based deep learning diagnostic models will enhance diagnostic accuracy.

• Tuberculosis and Respiratory Diseases
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• 제87권3호
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• pp.282-291
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• 2024

The increasing incidence of incidental pulmonary nodules necessitates effective biopsy techniques for accurate diagnosis and treatment planning. This paper reviews the widely used advanced bronchoscopic techniques, such as radial endobronchial ultrasound-guided transbronchial lung biopsy, electromagnetic navigation bronchoscopy, and the cutting-edge robotic-assisted bronchoscopy. In addition, the cryobiopsy technique, which can enhance diagnostic yield by combination with conventional biopsy tools, is described for application to peripheral pulmonary lesions and mediastinal lesions, respectively.

• Nuclear Engineering and Technology
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• 제37권2호
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• pp.127-138
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• 2005

Approaches to several recent issues in the operation of nuclear power plants using computational intelligence are discussed. These issues include 1) noise analysis techniques, 2) on-line monitoring and sensor validation, 3) regularization of ill-posed surveillance and diagnostic measurements, 4) transient identification, 5) artificial intelligence-based core monitoring and diagnostic system, 6) continuous efficiency improvement of nuclear power plants, and 7) autonomous anticipatory control and intelligent-agents. Several changes to the focus of Computational Intelligence in Nuclear Engineering have occurred in the past few years. With earlier activities focusing on the development of condition monitoring and diagnostic techniques for current nuclear power plants, recent activities have focused on the implementation of those methods and the development of methods for next generation plants and space reactors. These advanced techniques are expected to become increasingly important as current generation nuclear power plants have their licenses extended to 60 years and next generation reactors are being designed to operate for extended fuel cycles (up to 25 years), with less operator oversight, and especially for nuclear plants operating in severe environments such as space or ice-bound locations.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 제4회 영호남학술대회 논문집
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• pp.142-145
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• 2002

This paper describes an influence of system voltage harmonics on arrester deterioration diagnostic techniques based on leakage current measurement because the resistive current is composed of two components caused by nonlinear characteristics of arrester and by system voltage harmonics. Resistive leakage currents of arresters, which can be evaluated by the third harmonic component of total leakage currents, increase with its deterioration progress. In this paper, we developed a PSpice model for ZnO arrester to simulate the harmonics' effect described above. In simulation, pure sinusoidal voltage and the $3^{rd}$ harmonic voltage are applied to the model, and the leakage current changes are compared. The simulation results showed that the magnitudes of resistive leakage current depend not only on the phase of system voltage harmonics but also on the magnitude of it.

• Clinical Endoscopy
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• 제55권5호
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• pp.637-644
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• 2022

Background/Aims: Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is integral to the diagnosis of gastrointestinal (GI) subepithelial tumors (SETs). The impact of different EUS-FNB tissue sampling techniques on specimen adequacy and diagnostic accuracy in SETs has not been fully evaluated. This study aimed to compare the diagnostic outcomes of slow-pull (SP) and standard suction (SS) in patients with GI SETs. Methods: In this retrospective comparative study, 54 patients were enrolled. Medical records were reviewed for location and size of the target lesion, FNB needle type/size, technical order, specimen adequacy, diagnostic yield, and adverse events. The acquisition rate of adequate specimens and diagnostic accuracy were compared according to EUS-FNB techniques. Results: The mean lesion size was 42.6±36.4 mm, and most patients were diagnosed with GI stromal tumor (75.9%). The overall diagnostic accuracies of the SP and SS techniques were 83.3% and 81.5%, respectively (p=0.800). The rates of obtaining adequate core tissue were 79.6% and 75.9%, respectively (p=0.799). No significant clinical factors affected the rate of obtaining adequate core tissue, including lesion location and size, FNB needle size, and final diagnosis. Conclusions: SP and SS had comparable diagnostic accuracies and adequate core tissue acquisition for GI SETs via EUS-FNB.

• Tuberculosis and Respiratory Diseases
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• 제56권3호
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• pp.241-247
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• 2004

In the diagnostic evaluation of thoracic lesions, the image-guided transthoracic needle biopsy was developed, and its role was expanded with the development of cross-sectional detection and characterization of thoracic lesions and advances in biopsy needle design and techniques. Particularly for diagnostic evaluation of solitary pulmonary nodules, transthoracic needle biopsy has emerged as the invasive procedure of choice. This article covers the indication, the pre-procedure preparation, various guidance-modalities and techniques, and complications.