• KIEE International Transactions on Power Engineering
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• 제5A권1호
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• pp.40-45
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• 2005

Substation facilities have become extremely large and complex parts of electric power systems. The development of condition monitoring and diagnosis techniques has been a very significant factor in the improvement of substation transformer security. This paper presents a method to analyze the cause, the degree, and the aging process power transformers by the Self Organizing Map (SOM) method. Dissolved gas data were non-linearly transformed by the sigmoid function in SOM that works much the same way as the human decision making process. The potential for failure and the degree of aging of normal transformers are identified by using the proposed quantitative criterion. Furthermore, transformer aging is monitored by the proposed criterion for a set of transformers. To demonstrate the validity of the proposed method, a case study is performed and its results are presented.

• 동력기계공학회지
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• 제17권4호
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• pp.31-35
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• 2013

The emergency AC power supply system of the nuclear power plant is designed to supply the power to the nuclear power plant at the emergency operating condition. The safety function of the diesel generator at the nuclear power plant is to supply AC electric power to the safety system whenever the preferred AC power supply is unavailable. The reliable operation of onsite standby diesel generator should be ensured by a condition monitoring system designed to maintain, monitor and forecast the reliability level of diesel generator. The purpose of this paper is to improve the existing ultrasonic sensor used for condition diagnosis of engine fuel pump and cylinder head for the accurate diagnosis in actual engine condition of emergency diesel generator(EDG). As a result of this study, we could design and develop much more reliable ultrasonic sensor than existing ones.

• Journal of Chest Surgery
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• 제23권3호
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• pp.588-593
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• 1990

The rupture of tracheobronchial tree caused by non penetrating blunt trauma is being increased in incidence though it is still rarely occurred on now Because this type of injury is uncommon, a high index of suspicion should be maintained in all crush injuries involving the chest. Early diagnosis and primary repair not only restore normal lung function but also avoid the difficulties and complications associated with delayed diagnosis and repair. We experienced a case of tracheobronchial rupture caused by non penetrating blunt chest trauma without rib fracture. The patient was a 16 year old male who was a high school student. He was compressed on anterior chest by hand ball goal post being failed down on the morning of admission day. After this accident, he was suffered from progressively developing dyspnea and subcutaneous emphysema on face, neck and anterior chest. The diagnosis, tracheal rupture, was made by chest CT and bronchoscopy. After right thoracotomy, the ruptured site was directly closed by using interrupted suture. Post-operative course was uneventful. Thus we report this case of traumatic tracheal rupture with review of literature.

• Journal of Yeungnam Medical Science
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• 제36권3호
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• pp.163-182
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• 2019

The primary function of intraoperative frozen consultation is to provide an as accurate and prompt diagnosis as possible during surgery and to guide the surgeon in further management. However, the evaluation of frozen section (FS) is sometimes difficult because of suboptimal tissue quality and frozen artifacts compared with routinely processed tissue section. The pathologist responsible for the FS diagnosis requires experience and good judgment. Ovarian tumors are a heterogeneous group of tumors including primary surface epithelial tumors, germ cell tumors and sex cord-stromal tumors, secondary tumors, and other groups of tumors of uncertain histogenesis or nonspecific stroma. Intraoperative FS is a very important and reliable tool that guides the surgical management of ovarian tumors. In this review, the diagnostic key points for the pathologist and the implication of the FS diagnosis on the operator's decisions are discussed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제49권1호
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• pp.49-52
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• 2023

Osteoblastoma is a rare benign neoplasm formed by osteoid tissue and well-vascularized bone that occurs mainly in children and adolescents. It appears primarily in the long bones, vertebral column, and small bones of the hands and feet, and not typically in the skull and maxillary bones. The purpose of this study is to present the case of an 8-year-old girl with a diagnosis of right mandibular osteoblastoma and a review of the relevant literature. The goals of treatment were to preserve dental occlusion, masticatory function and facial symmetry while minimizing the effects on patient body image and quality of life. Osteoblastoma, although it is benign, can be aggressive, and its treatment will depend on the timing of diagnosis, size and location. Early diagnosis is essential to avoid not only radical surgery as in the case presented, but also to help minimize the risk of possible relapse and potential malignancy of a benign osteoblastoma.

• 한국정밀공학회지
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• 제12권11호
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• pp.82-90
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• 1995

This paper pressents a condition-based maintenance (CBM) method through bibration analysis. The well known frequency analysis is employed for performing machine fault diagnosis. The statistical control chart is also applied for analyzing the trend of the bearing wear. Vibration sensors are attached to prototype machine and signals are continuously monitored. The sampled data are utilized to evaluate how well the fast fourier transform(FFT) and the statistical control chart techniques could be used to identify defects of machine and to analyze the machine degradation. Experimental results show that the propowed approach could classify every mal-function and could be utilized for real machine diagnosis system.

• Journal of Digestive Cancer Research
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• 제1권2호
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• pp.95-99
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• 2013

MicroRNA (miRNA) dysregulations are associated with various types of human cancers, and miRNAs can function as tumor suppressors and oncogenes. Emerging evidence has shown that miRNA pathway is also altered during colorectal tumorigenesis. The detection of cancer-related miRNAs in stool samples may become useful diagnostic marker for colorectal cancer, because miRNAs in stool samples has high stability, and maintains a high portion of its original level. Recent studies reported that stool-based miRNAs can offer more sensitivity and specificity than currently used stool-based screening methods for CRC. In addition, unlike fecal occult blood test, sampling on consecutive dates and special dietary restrictions are not required. In this review, the authors discuss stool-based miRNA for the early diagnosis of CRC and perspectives on future application.

• 한국멀티미디어학회논문지
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• 제22권10호
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• pp.1168-1177
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• 2019

In order to diagnose and prevent Alzheimer's Disease (AD), it is becoming increasingly important to develop a CAD(Computer-aided Diagnosis) system for AD diagnosis, which provides effective treatment for patients by analyzing 3D MRI images. It is essential to apply powerful deep learning algorithms in order to automatically classify stages of Alzheimer's Disease and to develop a Alzheimer's Disease support diagnosis system that has the function of detecting hippocampus and CSF(Cerebrospinal fluid) which are important biomarkers in diagnosis of Alzheimer's Disease. In this paper, for AD diagnosis, we classify a given MRI data into three categories of AD, mild cognitive impairment, and normal control according by applying 3D brain MRI image to the Faster R-CNN model and detect hippocampus and CSF in MRI image. To do this, we use the 2D MRI slice images extracted from the 3D MRI data of the Faster R-CNN, and perform the widely used majority voting algorithm on the resulting bounding box labels for classification. To verify the proposed method, we used the public ADNI data set, which is the standard brain MRI database. Experimental results show that the proposed method achieves impressive classification performance compared with other state-of-the-art methods.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권8호
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• pp.4123-4141
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• 2019

Autonomous driving technology is divided into 0~5 levels. Of these, Level 5 is a fully autonomous vehicle that does not require a person to drive at all. The automobile industry has been trying to develop Level 5 to satisfy safety, but commercialization has not yet been achieved. In order to commercialize autonomous unmanned vehicles, there are several problems to be solved for driving safety. To solve one of these, this paper proposes 'A Deep Learning Part-diagnosis Platform(DLPP) based on an In-vehicle On-board gateway for an Autonomous Vehicle' that diagnoses not only the parts of a vehicle and the sensors belonging to the parts, but also the influence upon other parts when a certain fault happens. The DLPP consists of an In-vehicle On-board gateway(IOG) and a Part Self-diagnosis Module(PSM). Though an existing vehicle gateway was used for the translation of messages happening in a vehicle, the IOG not only has the translation function of an existing gateway but also judges whether a fault happened in a sensor or parts by using a Loopback. The payloads which are used to judge a sensor as normal in the IOG is transferred to the PSM for self-diagnosis. The Part Self-diagnosis Module(PSM) diagnoses parts itself by using the payloads transferred from the IOG. Because the PSM is designed based on an LSTM algorithm, it diagnoses a vehicle's fault by considering the correlation between previous diagnosis result and current measured parts data.

• Journal of Korean Neurosurgical Society
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• 제53권4호
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• pp.228-234
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• 2013

Objective : We have limited understanding on the presentation and survival of primary spinal sarcomas. The survival, recurrence rate, and related prognostic factors were investigated after treatment for primary sarcomas of the spine. Methods : Retrospective analysis of medical records and radiological data was done for 29 patients in whom treatment was performed due to primary sarcoma of the spine from 2000 to 2010. As for treatment method, non-radical operation, radiation therapy, and chemotherapy were simultaneously or sequentially combined. Overall survival (OS), progression free survival (PFS), ambulatory function, and pain status were analyzed. In addition, factors affecting survival and recurrence were analyzed : age (${\leq}42$ or ${\geq}43$), gender, tumor histologic type, lesion location (mobile spine or rigid spine), weakness at diagnosis, pain at diagnosis, ambulation at diagnosis, initial treatment, radiation therapy, kind of irradiation, surgery, chemotherapy and distant metastasis. Results : Median OS was 60 months, the recurrence rate was 79.3% and median PFS was 26 months. Patients with distant metastasis showed significantly shorter survival than those without metastasis. No factors were found to be significant relating to recurrence. Prognostic factor associated with walking ability was the presence of weakness at diagnosis. Conclusion : Primary spinal sarcomas are difficult to cure and show high recurrence rate. However, the development of new treatment methods is improving survival.