• The Journal of the Korea Contents Association
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• v.7 no.3
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• pp.25-33
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• 2007

The unexpected failure may cause a break in power system and loss of profits. Therefore it Is important to prevent abrupt faults by monitoring the condition of power systems. In this paper, we develop intelligent diagnosis technique for predicting faults of power transformer which plays an important role in the transmission and distribution systems among the various power facilities by using FCM and SOM. More specifically, FCM is used to select the efficient training data and reducing learning process time and SOM is used to diagnosis the power transformer. The proposed technique makes it possible to measures the possibility of aging as well as the faults occurred in transformer To demonstrate the validity of proposed method, various experiments are performed and their results are presented.

• Journal of Electrical Engineering and Technology
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• v.2 no.2
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• pp.157-164
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• 2007

Diagnosis techniques based on the dissolved gas analysis(DGA) have been developed to detect incipient faults in power transformers. Various methods exist based on DGA such as IEC, Roger, Dornenburg, and etc. However, these methods have been applied to different problems with different standards. Furthermore, it is difficult to achieve an accurate diagnosis by DGA without experienced experts. In order to resolve these drawbacks, this paper proposes a novel diagnosis method using fuzzy clustering and a radial basis neural network(RBFNN). In the neural network, fuzzy clustering is effective for selecting the efficient training data and reducing learning process time. After fuzzy clustering, the RBF neural network is developed to analyze and diagnose the state of the transformer. The proposed method measures the possibility and degree of aging as well as the faults occurred in the transformer. To demonstrate the validity of the proposed method, various experiments are performed and their results are presented.

• Journal of the Korean Society of Radiology
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• v.84 no.6
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• pp.1211-1219
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• 2023

Korea is rapidly entering into an aging society, and an increasing socioeconomic burden related to prostate cancer is inevitable. Therefore, the need for early detection and accurate diagnosis of prostate cancer is becoming increasingly critical. Ideally, a biopsy should accurately detect cancers using a minimum number of cores. However, as prostate cancer is often indistinguishable on imaging, image-guided targeted biopsies alone are insufficient for diagnosis. After decades of trial and error, the diagnosis of prostate cancer relies heavily on systematic biopsy, which is characterized by random and repetitive core acquisition throughout the gland. This review will provide an overview of the historical aspects of prostate cancer diagnosis. Moreover, the review will also address the general considerations involved in prostate biopsy, and discuss the periprocedural management of the patients.

• Anatomy and Cell Biology
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• v.56 no.2
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• pp.185-190
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• 2023

The root canal morphology undergoes aging-related changes, and relevant quantitative analyses have not yet been reported. We compared the cone beam computed tomography (CBCT) and micro-computed tomography (microCT) scans of extracted mandibular incisors to check the accuracy of morphological measurements. Thereafter, the root canal morphology and aging-related changes in the mandibular incisors of Japanese individuals were assessed using CBCT. Six extracted teeth were fixed in a phantom head and imaged using CBCT and micro-CT. The correlation between the findings of the two imaging modalities was examined. Further, CBCT reconstructed images of the mandibular incisors of 81 individuals were observed. Age-related changes of the root canals were compared between participants aged <30 years and those aged ≥30 years. The CBCT and micro-CT findings regarding the root canals of the extracted teeth coincided in 94.4% of the cases. Mandibular incisors exhibiting two root canals in either cross-section accounted for 9.9% of central incisors and 12.4% of lateral incisors. Mandibular central incisors with two root canals were observed in two (6.3%) individuals aged <30 years and six (12.2%) aged ≥30 years. Mandibular lateral incisors with two root canals were observed in one (3.1%) individual aged <30 years and nine (18.4%) aged ≥30 years. CBCT allows accurate evaluation of complex root canal morphologies and is useful for endodontic preoperative assessment. Mandibular incisors have more frequent occurrence of two root canals with aging.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.251-254
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• 2004

The aging diagnosis technique using partial discharge detection method detects partial discharge signals cause of power equipment failuer and able to forecast the aging state of insulation system through analysis algorithm, in this paper accumulates HFPD signal during constant scheduled cycles to build HFPD pattern and then analyzes HFPD pattern using statistical parameters and ${\Delta}F$ pattern. The 3D pattern is composed of detected signal frequency, amplitude and repeated number and the FRPDA(frequency resolved partial discharge analysis) technique is used in 3D pattern construction. The ${\Delta}F$ pattern shows variation characteristics of amplitude gradient of consecutive HFPD signal Pulses and able to classify discharge types-internal discharge, surface discharge and coronal discharge etc. Fractal mathematics applied to ${\Delta}F$ pattern quantification and neural networks is used in aging diagnostic algorithm.

• The Korean journal of internal medicine
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• v.33 no.6
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• pp.1039-1049
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• 2018

The populations of Asian countries are expected to age rapidly in the near future, with a dramatic increase in the number of heart failure (HF) patients also anticipated. The need for palliative and end-of-life care for elderly patients with advanced HF is currently recognized in aging societies. However, palliative care and active treatment for HF are not mutually exclusive, and palliative care should be provided to reduce suffering occurring at any stage of symptomatic HF after the point of diagnosis. HF patients are at high risk of sudden cardiac death from the early stages of the disease onwards. The decision of whether to perform cardiopulmonary resuscitation in the event of an emergency is challenging, especially in elderly HF patients, because of the difficulty in accurately predicting the prognosis of the condition. Furthermore, advanced HF patients are often fitted with a device, and device deactivation at the end of life is a complicated process. Treatment strategies should thus be discussed by multi-disciplinary teams, including palliative experts, and should consider patient directives to address the problems discussed above. Open communication with the HF patient regarding the expected prognosis, course, and treatment options will serve to support the patient and aid in future planning.

• Integrative Medicine Research
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• v.5 no.3
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• pp.176-181
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• 2016

Recent studies have focused on evidence-based interventions to prevent mobility decline and enhance physical performance in older adults. Several modalities, in addition to traditional strengthening programs, have been designed to manage age-related functional decline more effectively. In this study, we reviewed the current relevant literatures to assess the therapeutic potential of eccentric exercises for age-related muscle atrophy (sarcopenia). Age-related changes in human skeletal muscle, and their relationship with physical performance, are discussed with reference to in vitro physiologic and human biomechanics studies. An overview of issues relevant to sarcopenia is provided in the context of the recent consensus on the diagnosis and management of the condition. A decline in mobility among the aging population is closely linked with changes in the muscle force-velocity relationship. Interventions based specifically on increasing velocity and eccentric strength can improve function more effectively compared with traditional strengthening programs. Eccentric strengthening programs are introduced as a specific method for improving both muscle force and velocity. To be more effective, exercise interventions for older adults should focus on enhancing the muscle force-velocity relationship. Exercises that can be performed easily, and that utilize eccentric strength (which is relatively spared during the aging process), are needed to improve both muscle force and velocity.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1216-1216
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• 2015

In this study, the author apply the VLF(Very Low Frequency) tan-delta data that has been measured at each office of the KEPCO 2012 to the Weibull distribution which is the statistical analysis as previous studies for the remaining life prediction through the improvement of the sensitivity and reliability of the degradation state assessment of underground distribution power cables. Also, in this paper, UCD(Used Cable Diagnosis) Matrix proposed by KEPCO was applied to the hierarchy of assessment prioritization. it suggests Aging Index for condition assessment and high reliability of proper economic replacement cycle using the weight according to the assessment prioritization.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.3
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• pp.121-129
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• 2001

In this paper, a new efficient feature extraction method based on Daubechies discrete wavelet transform is presented. This paper especially deals with the assessment of process statistical parameter using the features extracted from the wavelet coefficients of measured acoustic emission signals. Since the parameter assessment using all wavelet coefficients will often turn out leads to inefficient or inaccurate results, we selected that level-3 stage of multi decomposition in discrete wavelet transform. We make use of the feature extraction parameter namely, maximum value of acoustic emission signal, average value, dispersion, skewness, kurtosis, etc. The effectiveness of this new method has been verified on ability a diagnosis transformer go through feature extraction in stage of aging(the early period, the middle period, the last period)

• Sleep Medicine and Psychophysiology
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• v.8 no.1
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• pp.18-21
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• 2001

The change of sleep pattern is one of the most often altered normal physiological functions in elderly people. Besides normal change of sleep, insomnia and sleep apnea syndrome (SAS) are (one of) the main complaints. In addition, parasomnia is also frequent in this age group. Several parasomnias frequently found in the elderly are reviewed. Periodic limb movements in sleep (PLMS), restless legs syndrome (RLS), and REM sleep behavior disorder are the most frequent parasomnias in old age. Most parasomnias could be diagnosed by polysomnography, and be treated easily. Therefore, early and precise diagnosis and management for parasomnia in aging people are needed.