• 한국기계가공학회지
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• 제19권9호
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• pp.47-52
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• 2020

With the 4th industrial revolution, condition monitoring using machine learning techniques has become popular among researchers. An overload due to complex operations causes several irregularities in MOSFETs. This study investigated the acquired voltage to analyze the overcurrent effects on MOSFETs using a failure mode effect analysis (FMEA). The results indicated that the voltage pattern changes greatly when the current is beyond the threshold value. Several features were extracted from the collected voltage signals that indicate the health state of a switched-mode power supply (SMPS). Then, the data were reduced to a smaller sample space by using a principal component analysis (PCA). A robust machine learning algorithm, the support vector machine (SVM), was used to classify different health states of an SMPS, and the classification results are presented for different parameters. An SVM approach assisted by a PCA algorithm provides a strong fault diagnosis framework for an SMPS.

• Journal of Platform Technology
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• 제10권1호
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• pp.20-28
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• 2022

인공지능기반의 건강 데이터 검증은 임상 연구에 도움을 줄 뿐만 아니라, 새로운 치료법을 개발하는데 필수 요소가 되었다. 미국 식품의약 관리국이 의학진단 분야 중 인공지능을 이용하여 성인 당뇨병 환자의 경증 이상 당뇨병성 망막증을 감지하는 의료기기 마케팅을 승인한 이래, 인공지능을 이용한 테스트가 증가하고 있다. 본 연구에서는 구글에서 지원하는 Teachable Machine 을 이용하여 이미지 분류 기반의 인공지능모델을 생성하고, 학습을 통한 예측 모델을 완성하였다. 이는 현재 만성질환의 환자들 중 발생하는 안구 질환 중 백내장의 조기 발견하는데 용이하게 할 뿐만 아니라, 눈 건강을 위해 헬스케어 프로그램으로 안 질환 예방을 위한 디지털 개인건강 헬스케어 앱을 개발하기 위한 기초 연구로 진행되었다.

• 안전기술
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• 28호
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• pp.54-55
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• 2000

• Nuclear Engineering and Technology
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• 제52권10호
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• pp.2262-2273
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• 2020

Digital twin technology can provide significant value for the prognostics and health management (PHM) of critical plant components by improving insight into system design and operating conditions. Digital twinning of systems can be utilized for anomaly detection, diagnosis and the estimation of the system's remaining useful life in order to optimize operations and maintenance processes in a nuclear plant. In this regard, a conceptual framework for the application of digital twin technology for the prognosis of Control Element Drive Mechanism (CEDM), and a data-driven approach to anomaly detection using coil current profile are presented in this study. Health management of plant components can capitalize on the data and signals that are already recorded as part of the monitored parameters of the plant's instrumentation and control systems. This work is focused on the development of machine learning algorithm and workflow for the analysis of the CEDM using the recorded coil current data. The workflow involves features extraction from the coil-current profile and consequently performing both clustering and classification algorithms. This approach provides an opportunity for health monitoring in support of condition-based predictive maintenance optimization and in the development of the CEDM digital twin model for improved plant safety and availability.

• International Journal of Internet, Broadcasting and Communication
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• 제15권4호
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• pp.311-325
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• 2023

In the construction machinery rental market, there are frequent cases of sublease through large-scale rental companies or rental through mediation organizations without legal grounds. In addition, institutional improvement of the construction machine safety management system has been required due to concerns over the internalization of legal inspections due to the lack of type approval data and construction machine history management during the construction machine inspection process. The government is responsible for securing safety of construction machinery and promoting mechanization of construction machinery by efficiently managing the construction machinery market by setting safety management such as type approval, registration, and inspection of construction machinery. In order to efficiently implement this, it is required to establish a platform for renting construction machinery and collecting safety management information. We presented a plan to build a public platform for construction machinery to secure the soundness of the construction machinery rental market and to improve safety management.

• 한국전자통신학회논문지
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• 제18권1호
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• pp.85-90
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• 2023

보건의료분야 데이터 분석 방법론이 기존의 통계 중심의 연구방법에서 머신러닝을 이용한 예측 연구로 전환되고 있다. 본 연구에서는 다양한 머신러닝 도구들을 살펴보고, 보건의료분야에서 많이 사용하고 있는 통계 도구인 R을 빅데이터 머신러닝에 적용하기 위해 R과 스파크를 연계한 프로그래밍 모델들을 비교한다. 그리고, R을 스파크 환경에서 수행하는 SparkR을 이용한 선형회귀모델 학습의 성능을 스파크의 기본 언어인 스칼라를 이용한 모델과 비교한다. 실험 결과 SparkR을 이용할 때의 학습 수행 시간이 스칼라와 비교하여 10~20% 정도 증가하였다. 결과로 제시된 성능 저하를 감안한다면 기존의 통계분석 도구인 R을 그대로 활용 가능하다는 측면에서 SparkR의 분산 처리의 유용성을 확인하였다.

• Smart Structures and Systems
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• 제29권1호
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• pp.93-103
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• 2022

With the wider availability of sensor technology through easily affordable sensor devices, several Structural Health Monitoring (SHM) systems are deployed to monitor vital civil infrastructure. The continuous monitoring provides valuable information about the health of the structure that can help provide a decision support system for retrofits and other structural modifications. However, when the sensors are exposed to harsh environmental conditions, the data measured by the SHM systems tend to be affected by multiple anomalies caused by faulty or broken sensors. Given a deluge of high-dimensional data collected continuously over time, research into using machine learning methods to detect anomalies are a topic of great interest to the SHM community. This paper contributes to this effort by proposing a relatively new time series representation named "Shapelet Transform" in combination with a Random Forest classifier to autonomously identify anomalies in SHM data. The shapelet transform is a unique time series representation based solely on the shape of the time series data. Considering the individual characteristics unique to every anomaly, the application of this transform yields a new shape-based feature representation that can be combined with any standard machine learning algorithm to detect anomalous data with no manual intervention. For the present study, the anomaly detection framework consists of three steps: identifying unique shapes from anomalous data, using these shapes to transform the SHM data into a local-shape space and training machine learning algorithms on this transformed data to identify anomalies. The efficacy of this method is demonstrated by the identification of anomalies in acceleration data from an SHM system installed on a long-span bridge in China. The results show that multiple data anomalies in SHM data can be automatically detected with high accuracy using the proposed method.

• International Journal of Computer Science & Network Security
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• 제23권12호
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• pp.225-234
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• 2023

In this era of information and communication technology (ICT), tremendous improvements have been witnessed in our daily lives. The impact of these technologies is subjective and negative or positive. For instance, ICT has brought a lot of ease and versatility in our lifestyles, on the other hand, its excessive use brings around issues related to physical and mental health etc. In this study, we are bridging these both aspects by proposing the idea of AI based mental healthcare (AIMS). In this regard, we aim to provide a platform where the patient can register to the system and take consultancy by providing their assessment by means of a chatbot. The chatbot will send the gathered information to the machine learning block. The machine learning model is already trained and predicts whether the patient needs a treatment by classifying him/her based on the assessment. This information is provided to the mental health practitioner (doctor, psychologist, psychiatrist, or therapist) as clinical decision support. Eventually, the practitioner will provide his/her suggestions to the patient via the proposed system. Additionally, the proposed system prioritizes care, support, privacy, and patient autonomy, all while using a friendly chatbot interface. By using technology like natural language processing and machine learning, the system can predict a patient's condition and recommend the right professional for further help, including in-person appointments if necessary. This not only raises awareness about mental health but also makes it easier for patients to start therapy.

• 한국콘텐츠학회논문지
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• 제10권10호
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• pp.54-67
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• 2010

종래에 헬스케어 영역에서 주로 사용해왔던 기계학습 기법을 U-health 서비스 분석단계에 적용하기에는 여러 가지 문제점들이 있다. 첫째, 아직 U-health 분야의 연구가 초기단계에 불과하여 기존의 기법들을 U-health 환경에 적용한 사례가 매우 부족하다. 둘째, 기계학습 기법은 학습시간이 많이 소요되기 때문에 실시간으로 질환을 관리해야만 하는 U-health 서비스 환경에는 적용하기 어렵다. 셋째, 그동안 다양한 기계 학습 기법들이 제시되었으나 질환 연관변수에 가중치를 부여할 수 있는 방법이 없어, 개인 맞춤형 질병예측 시스템으로 구축할 수 없는 한계를 가진다. 본 논문에서는 이러한 문제점들을 개선하고, U-health 서비스 시스템의 바이오 데이터 분석 과정을 프로세스로 해석하기 위하여, 개인 맞춤형 질병예측 기법인 PCADP를 제안하였다. 또한 이러한 PCADP를 바탕으로 U-health 데이터 및 서비스 명세의 의미 있는 표현을 위하여 U-health 온톨로지 프레임워크를 시멘틱스형으로 모델링하였다. 또한 PCADP 예측 기법은 U-health 환경에서 판별 기법이 갖추어야 할 조건인 유연성과 실시간성이 기존의 방식에 비하여 향상되었고, 판별과정의 모니터링 및 시스템의 지속적인 개선측면에서도 효율적으로 작용함을 확인하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1153-1157
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• 2004

The report of the Korean National Statistics Office shows that Korea has been emerging as an elderly society rapidly, and it will burden the Korean society with excessive social welfare cost for the aged in the near future. If we can help the aged to live healthy in some ways, the social burden for the health care of the aged will be lessened. In order to help physical and mental health of the elderly person, we have developed an exercise apparatus called intelligent arm wrestling machine system. This paper presents the mechanism and scenario of the proposed intelligent arm wrestling machine system. The proposed mechanism and scenario are peculiar. In particular, the proposed scenario determines randomly who will win between the man and the robot and generates a game process that the arm-wrestler cannot predict in advance.