• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(1)
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• pp.97-101
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• 2003

In this paper, we propose a new diagnosis method of DC/UC converter aging. The method is based on parasitic resister change with aging process. we apply to on-line diagnosis of DC/DC converter because of observing not a device but a system. We present the mathematical analysis and experimental study.

• 전기학회논문지
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• 제56권4호
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• pp.724-729
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• 2007

In this paper, we propose a new diagnosis method of DC/DC converter aging. The method is based on variations of the parasitic resistor for the aging process. We apply an on-line diagnosis of the DC/DC converter because the observation is not a device, but a system. This study proposes a method of DC/DC converter diagnosis by analyzing the variations of model on the variations of parasitic resistor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.1278-1280
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• 2004

In this paper, we propose a new diagnosis method of DC/DC converter aging. The method is based on the variations of parasitic resistor for the aging process. We apply an on-line diagnosis of DC/DC converter because the observation is not a device, but a system. This study proposes a method of DC/DC converter diagnosis by analyzing the variations of model on the variations of parasitic resistor.

• International Journal of Internet, Broadcasting and Communication
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• 제14권2호
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• pp.129-135
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• 2022

Currently, the rapid growth of electric vehicles and the collection and disposal of waste batteries are becoming a social problem. The purpose of this paper is to propose a fast and efficient battery screening method through a safe inspection and storage method according to the collection and storage of waste batteries of electric vehicles. In addition, as the resistance inside the waste battery increases, an instantaneous voltage drop occurs, and there is a risk of overcharging and overdischarging compared to the initial state of the battery. Accordingly, there are great difficulties in operation, so the final goal of this study is to develop a device for diagnosing aging through real-time battery internal resistance measurement. Final result As a result of simulation of the internal resistance measurement test circuit through external impedance (AC), the actual simulation value was 0.05Ω, RS = Vrms / Irms => Vrms = 8.0036mV, Irms = 162.83Ma. Substitute the suggested method. The result was calculated as Rs = 0.0495Ω. It is possible to measure up to 64 impedances inside the aging diagnostic equipment that enables real-time monitoring of the developed battery cells, and the range can be changed according to the application method.

• 한국산학기술학회논문지
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• 제22권6호
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• pp.27-35
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• 2021

일반적으로, 태양광모듈은 20년 이상의 장기간 동안 사용할 수 있다고 알려져 있지만, 설치된 주변 환경요인(염분, 온도, 습도, 자외선, 음영 등)에 따라 다양한 열화현상이 발생하여, 전기적 성능과 수명이 크게 감소할 수 있어 태양광 모듈에 대한 정확한 열화특성 분석이 요구되고 있다. 그러나, 태양광모듈의 출력을 STC조건으로 보정하여 초기 사양과 비교분석하는 기존의 열화특성 분석방법은 데이터 보정 시 필연적으로 발생하는 데이터 오류로 인하여 객관성이 결여될 수 있다. 따라서, 본 논문에서는 태양광전원 모듈부와 모니터링부로 구성된 열화진단 시험장치를 구축하여 모듈별 출력 데이터를 측정 및 수집하고, 태양광모듈의 출력 변동성과 통신 에러 및 지연에 따른 영향을 최소화하기 위하여, MATLAB을 이용한 열화특성 분석 모델링을 통하여 실측 데이터를 평활화한다. 또한, 이를 바탕으로 태양광모듈의 열화 상태를 계절별 실측 출력특성에 따라 분석한 결과, 전체 구형모듈의 평균 열화율은 총 25.73%이고, 연평균 1.55%씩 열화됨을 진단할 수 있어, 본 논문에서 구축한 열화진단 시험장치의 유용성을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.1275-1277
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• 2004

In this paper, we propose a new diagnosis method of DC/DC converter aging. The method is based on the variations of parasitic resistor for the aging process. We apply an on-line diagnosis of DC/DC converter because the observation is not a device, but a system. This study proposes a method of DC/DC converter diagnosis by analyzing the variations of model on the variations of parasitic resistor.

• Design & Manufacturing
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• 제16권4호
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• pp.52-59
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• 2022

Currently, Korea is an aging society and is expected to become a super-aged society in about four years. X-ray devices are widely used for early diagnosis in hospitals, and many X-ray technologies are being developed. The development of X-ray device technology is important, but it is also important to increase the reliability of the device through accurate data management. Sensor nodes such as temperature, voltage, and current of the diagnosis device may malfunction or transmit inaccurate data due to various causes such as failure or power outage. Therefore, in this study, the temperature, tube voltage, and tube current data related to each sensor and detection circuit of the diagnostic X-ray imaging device were measured and analyzed. Based on QC data, device failure prediction and diagnosis algorithms were designed and performed. The fault diagnosis algorithm can configure a simulator capable of setting user parameter values, displaying sensor output graphs, and displaying signs of sensor abnormalities, and can check the detection results when each sensor is operating normally and when the sensor is abnormal. It is judged that efficient device management and diagnosis is possible because it monitors abnormal data values (temperature, voltage, current) in real time and automatically diagnoses failures by feeding back the abnormal values detected at each stage. Although this algorithm cannot predict all failures related to temperature, voltage, and current of diagnostic X-ray imaging devices, it can detect temperature rise, bouncing values, device physical limits, input/output values, and radiation-related anomalies. exposure. If a value exceeding the maximum variation value of each data occurs, it is judged that it will be possible to check and respond in preparation for device failure. If a device's sensor fails, unexpected accidents may occur, increasing costs and risks, and regular maintenance cannot cope with all errors or failures. Therefore, since real-time maintenance through continuous data monitoring is possible, reliability improvement, maintenance cost reduction, and efficient management of equipment are expected to be possible.

• The Korean journal of internal medicine
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• 제33권6호
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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.

• 공업화학전망
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• 제23권6호
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• pp.3-13
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• 2020

저출산 고령화 사회로의 진입은 대한민국뿐만 아니라 전 세계적으로 많은 사회 문제를 야기하고 있다. 그 중에서 고령 인구 증가로 인한 의료 수요 증가와 이를 뒷받침 할 의료인력 부족은 곧 다가올 사회문제이다. 4차 산업 혁명으로 인해 다양한 사회문제에 대한 혁신적인 해법들이 제시되고 있는데, 본 기고문에서는 다가올 고령화 사회에서 의료인력 부족 등에 의한 해결법으로 원격의료 지원을 위한 인공지능 활용을 다루고자 한다. 병 진단 및 예측을 위한 여러 가지 인공지능 알고리즘은 이미 많이 개발 되어 있으나, 일반적으로 딥러닝에 많이 쓰이는 인공신경망 구조인 합성곱 뉴럴네트워크(convolution neural network)나 기존 퍼셉트론(perceptron) 구조에서 벗어나 확률론적 인공신경망 중에 하나인 베이지안 뉴럴네트워크(Bayesian neural network)를 다루고자 한다. 그중에서 연산효율적이며 뉴로모픽 하드웨어로 구현 가능성이 높고 실제 진단 예측(diagnosis prediction) 문제 해결에 강점을 보이는 알고리즘으로써 naive Bayes classifer를 활용한 연구를 소개하고자 한다.

• 한국방사선학회논문지
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• 제15권2호
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• pp.159-164
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• 2021

진단용방사선발생장치를 이용한 검사는 영상의학과에서 인체 내 정보를 파악하기 위한 가장 유용한 진단장비 중 하나로 신뢰도가 매우 높다. 이와 같은 이유로, 최근에는 영상의학과 영역의 진단 검사 장비를 이용한 검사 건수가 매년 증가하고 있다. 또한, 검사 건수 증가는 장치의 빠른 노화를 불러일으키고 이로 인해 장치에 대한 정도관리(quality control, QC)의 중요성이 대두된다. 특히, 진단용방사선발생장치를 이용한 검사에서 정도관리란 검사시작부터 검사가 끝날 때 까지 발생할 수 있는 모든 문제점을 사전에 알아내고 대처하여 신뢰가 확보된 영상을 획득하여 제공하는 과정에 있는 일련의 모든 활동을 의미한다. 이에 본 연구에서는 진단용방사선발생장치를 이용한 검사에서 정도관리에 대해보고 한다.