• Title/Summary/Keyword: self-supervised learning

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Human Posture Recognition: Methodology and Implementation

  • Htike, Kyaw Kyaw;Khalifa, Othman O.
    • Journal of Electrical Engineering and Technology
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    • v.10 no.4
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    • pp.1910-1914
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    • 2015
  • Human posture recognition is an attractive and challenging topic in computer vision due to its promising applications in the areas of personal health care, environmental awareness, human-computer-interaction and surveillance systems. Human posture recognition in video sequences consists of two stages: the first stage is training and evaluation and the second is deployment. In the first stage, the system is trained and evaluated using datasets of human postures to ‘teach’ the system to classify human postures for any future inputs. When the training and evaluation process is deemed satisfactory as measured by recognition rates, the trained system is then deployed to recognize human postures in any input video sequence. Different classifiers were used in the training such as Multilayer Perceptron Feedforward Neural networks, Self-Organizing Maps, Fuzzy C Means and K Means. Results show that supervised learning classifiers tend to perform better than unsupervised classifiers for the case of human posture recognition.

The Identifier Recognition from Shipping Container Image by Using The Enhanced Self-Organized Supervised Learning Algorithm (개선된 자가생성 지도학습 알고리즘을 이용한 컨테이너 식별자 연식)

  • 이혜현;김태경;김광백
    • Proceedings of the Korea Multimedia Society Conference
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    • 2002.11b
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    • pp.149-154
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    • 2002
  • 운송 컨테이너의 식별자를 추출하고 인식하는 것은 컨테이너 식별자들의 크기나 위치가 정형화되어 있지 않고 외부의 잡음으로 인하여 식별자의 형태가 훼손되어 있기 때문에 어렵다. 본 논문에서는 이러한 특성을 고려하여 컨테이너 영상에 대해 Canny 에지 추출 기법을 이용하여 컨테이너의 식별자 영역을 추출하고 추출된 컨테이너 식별자 영역에서 히스토그램 방법과 윤곽선 추적 알고리즘을 결합하여 개별 식별자를 추출한다. 추출된 컨테이너 개별 식별자 인식은 ART1을 수정하여 지도 학습 방법과 결합한 개선된 자가생성 지도학습 알고리즘을 제안하여 적용한다. 실험결과에서는 제안된 컨테이너 식별자 추출 및 인식 방법이 다양한 컨테이너 영상에 대해 효율적인 것을 보인다.

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Tool Wear Monitoring in Milling Operation Using ART2 Neural Network (ART2 신경회로망을 이용한 밀링공정의 공구마모 진단)

  • Yoon, Sun-Il;Ko, Tae-Jo;Kim, Hee-Sool
    • Journal of the Korean Society for Precision Engineering
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    • v.12 no.12
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    • pp.120-129
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    • 1995
  • This study introduces a tool wear monitoring technology in face milling operation comprised of an unsupervised neural network. The monitoring system employs two types of sensor signal such as cutting force and acceleration in sensory detection state. The RMS value and band frequency energy of the sensor signals are calculated for te input patterns of neural network. ART2 neural network, which is capable of self organizing without supervised learning, is used for clustering of tool wear states. The experimental results show that tool wear can be effectively detected under various cutting conditions without prior knowledge of cutting processes.

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A Research on Using Wasserstein Distance as a Loss Function in Self-Supervised Learning (자기지도 학습에서 와서스타인 (Wasserstein) 거리의 손실함수로의 이용가능성 연구)

  • Koo, Inhwa;Chae, Dong-Kyu
    • Proceedings of the Korea Information Processing Society Conference
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    • 2022.11a
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    • pp.628-629
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    • 2022
  • 딥러닝의 높은 예측 정확도를 위해서는 많은 양의 학습 데이터가 필요하다. 그러나 실세계에서 많은 양의 레이블이 붙은 데이터를 구하는 것은 어렵고 많은 비용이 든다. 때문에 레이블이 없이도 양질의 표현 학습이 가능한 자기지도학습이 각광을 받고 있다. 와서스타인 거리는 생성모델에도 쓰이지만 의사 레이블 (pseudo label) 을 만들어 레이블이 없는 데이터들을 분류 하는데도 좋은 성능을 보이고 있다. 따라서. 본 연구는 와서스타인 거리를 자기지도학습에 접목시키는 방법을 제안한다. 실험을 통해 연구의 가능성을 보인다.

A Two-Stage Document Page Segmentation Method using Morphological Distance Map and RBF Network (거리 사상 함수 및 RBF 네트워크의 2단계 알고리즘을 적용한 서류 레이아웃 분할 방법)

  • Shin, Hyun-Kyung
    • Journal of KIISE:Software and Applications
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    • v.35 no.9
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    • pp.547-553
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    • 2008
  • We propose a two-stage document layout segmentation method. At the first stage, as top-down segmentation, morphological distance map algorithm extracts a collection of rectangular regions from a given input image. This preliminary result from the first stage is employed as input parameters for the process of next stage. At the second stage, a machine-learning algorithm is adopted RBF network, one of neural networks based on statistical model, is selected. In order for constructing the hidden layer of RBF network, a data clustering technique bared on the self-organizing property of Kohonen network is utilized. We present a result showing that the supervised neural network, trained by 300 number of sample data, improves the preliminary results of the first stage.

Anomaly Detection using Geometric Transformation of Normal Sample Images (정상 샘플 이미지의 기하학적 변환을 사용한 이상 징후 검출)

  • Kwon, Yong-Wan;Kang, Dong-Joong
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.4
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    • pp.157-163
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    • 2022
  • Recently, with the development of automation in the industrial field, research on anomaly detection is being actively conducted. An application for anomaly detection used in factory automation is camera-based defect inspection. Vision camera inspection shows high performance and efficiency in factory automation, but it is difficult to overcome the instability of lighting and environmental conditions. Although camera inspection using deep learning can solve the problem of vision camera inspection with much higher performance, it is difficult to apply to actual industrial fields because it requires a huge amount of normal and abnormal data for learning. Therefore, in this study, we propose a network that overcomes the problem of collecting abnormal data with 72 geometric transformation deep learning methods using only normal data and adds an outlier exposure method for performance improvement. By applying and verifying this to the MVTec data set, which is a database for auto-mobile parts data and outlier detection, it is shown that it can be applied in actual industrial sites.

Research on Developing a Conversational AI Callbot Solution for Medical Counselling

  • Won Ro LEE;Jeong Hyon CHOI;Min Soo KANG
    • Korean Journal of Artificial Intelligence
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    • v.11 no.4
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    • pp.9-13
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    • 2023
  • In this study, we explored the potential of integrating interactive AI callbot technology into the medical consultation domain as part of a broader service development initiative. Aimed at enhancing patient satisfaction, the AI callbot was designed to efficiently address queries from hospitals' primary users, especially the elderly and those using phone services. By incorporating an AI-driven callbot into the hospital's customer service center, routine tasks such as appointment modifications and cancellations were efficiently managed by the AI Callbot Agent. On the other hand, tasks requiring more detailed attention or specialization were addressed by Human Agents, ensuring a balanced and collaborative approach. The deep learning model for voice recognition for this study was based on the Transformer model and fine-tuned to fit the medical field using a pre-trained model. Existing recording files were converted into learning data to perform SSL(self-supervised learning) Model was implemented. The ANN (Artificial neural network) neural network model was used to analyze voice signals and interpret them as text, and after actual application, the intent was enriched through reinforcement learning to continuously improve accuracy. In the case of TTS(Text To Speech), the Transformer model was applied to Text Analysis, Acoustic model, and Vocoder, and Google's Natural Language API was applied to recognize intent. As the research progresses, there are challenges to solve, such as interconnection issues between various EMR providers, problems with doctor's time slots, problems with two or more hospital appointments, and problems with patient use. However, there are specialized problems that are easy to make reservations. Implementation of the callbot service in hospitals appears to be applicable immediately.

Diagnosis and prediction of periodontally compromised teeth using a deep learning-based convolutional neural network algorithm

  • Lee, Jae-Hong;Kim, Do-hyung;Jeong, Seong-Nyum;Choi, Seong-Ho
    • Journal of Periodontal and Implant Science
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    • v.48 no.2
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    • pp.114-123
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    • 2018
  • Purpose: The aim of the current study was to develop a computer-assisted detection system based on a deep convolutional neural network (CNN) algorithm and to evaluate the potential usefulness and accuracy of this system for the diagnosis and prediction of periodontally compromised teeth (PCT). Methods: Combining pretrained deep CNN architecture and a self-trained network, periapical radiographic images were used to determine the optimal CNN algorithm and weights. The diagnostic and predictive accuracy, sensitivity, specificity, positive predictive value, negative predictive value, receiver operating characteristic (ROC) curve, area under the ROC curve, confusion matrix, and 95% confidence intervals (CIs) were calculated using our deep CNN algorithm, based on a Keras framework in Python. Results: The periapical radiographic dataset was split into training (n=1,044), validation (n=348), and test (n=348) datasets. With the deep learning algorithm, the diagnostic accuracy for PCT was 81.0% for premolars and 76.7% for molars. Using 64 premolars and 64 molars that were clinically diagnosed as severe PCT, the accuracy of predicting extraction was 82.8% (95% CI, 70.1%-91.2%) for premolars and 73.4% (95% CI, 59.9%-84.0%) for molars. Conclusions: We demonstrated that the deep CNN algorithm was useful for assessing the diagnosis and predictability of PCT. Therefore, with further optimization of the PCT dataset and improvements in the algorithm, a computer-aided detection system can be expected to become an effective and efficient method of diagnosing and predicting PCT.

Performance of Investment Strategy using Investor-specific Transaction Information and Machine Learning (투자자별 거래정보와 머신러닝을 활용한 투자전략의 성과)

  • Kim, Kyung Mock;Kim, Sun Woong;Choi, Heung Sik
    • Journal of Intelligence and Information Systems
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    • v.27 no.1
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    • pp.65-82
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    • 2021
  • Stock market investors are generally split into foreign investors, institutional investors, and individual investors. Compared to individual investor groups, professional investor groups such as foreign investors have an advantage in information and financial power and, as a result, foreign investors are known to show good investment performance among market participants. The purpose of this study is to propose an investment strategy that combines investor-specific transaction information and machine learning, and to analyze the portfolio investment performance of the proposed model using actual stock price and investor-specific transaction data. The Korea Exchange offers daily information on the volume of purchase and sale of each investor to securities firms. We developed a data collection program in C# programming language using an API provided by Daishin Securities Cybosplus, and collected 151 out of 200 KOSPI stocks with daily opening price, closing price and investor-specific net purchase data from January 2, 2007 to July 31, 2017. The self-organizing map model is an artificial neural network that performs clustering by unsupervised learning and has been introduced by Teuvo Kohonen since 1984. We implement competition among intra-surface artificial neurons, and all connections are non-recursive artificial neural networks that go from bottom to top. It can also be expanded to multiple layers, although many fault layers are commonly used. Linear functions are used by active functions of artificial nerve cells, and learning rules use Instar rules as well as general competitive learning. The core of the backpropagation model is the model that performs classification by supervised learning as an artificial neural network. We grouped and transformed investor-specific transaction volume data to learn backpropagation models through the self-organizing map model of artificial neural networks. As a result of the estimation of verification data through training, the portfolios were rebalanced monthly. For performance analysis, a passive portfolio was designated and the KOSPI 200 and KOSPI index returns for proxies on market returns were also obtained. Performance analysis was conducted using the equally-weighted portfolio return, compound interest rate, annual return, Maximum Draw Down, standard deviation, and Sharpe Ratio. Buy and hold returns of the top 10 market capitalization stocks are designated as a benchmark. Buy and hold strategy is the best strategy under the efficient market hypothesis. The prediction rate of learning data using backpropagation model was significantly high at 96.61%, while the prediction rate of verification data was also relatively high in the results of the 57.1% verification data. The performance evaluation of self-organizing map grouping can be determined as a result of a backpropagation model. This is because if the grouping results of the self-organizing map model had been poor, the learning results of the backpropagation model would have been poor. In this way, the performance assessment of machine learning is judged to be better learned than previous studies. Our portfolio doubled the return on the benchmark and performed better than the market returns on the KOSPI and KOSPI 200 indexes. In contrast to the benchmark, the MDD and standard deviation for portfolio risk indicators also showed better results. The Sharpe Ratio performed higher than benchmarks and stock market indexes. Through this, we presented the direction of portfolio composition program using machine learning and investor-specific transaction information and showed that it can be used to develop programs for real stock investment. The return is the result of monthly portfolio composition and asset rebalancing to the same proportion. Better outcomes are predicted when forming a monthly portfolio if the system is enforced by rebalancing the suggested stocks continuously without selling and re-buying it. Therefore, real transactions appear to be relevant.

Pedestrian and Vehicle Distance Estimation Based on Hard Parameter Sharing (하드 파라미터 쉐어링 기반의 보행자 및 운송 수단 거리 추정)

  • Seo, Ji-Won;Cha, Eui-Young
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.3
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    • pp.389-395
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    • 2022
  • Because of improvement of deep learning techniques, deep learning using computer vision such as classification, detection and segmentation has also been used widely at many fields. Expecially, automatic driving is one of the major fields that applies computer vision systems. Also there are a lot of works and researches to combine multiple tasks in a single network. In this study, we propose the network that predicts the individual depth of pedestrians and vehicles. Proposed model is constructed based on YOLOv3 for object detection and Monodepth for depth estimation, and it process object detection and depth estimation consequently using encoder and decoder based on hard parameter sharing. We also used attention module to improve the accuracy of both object detection and depth estimation. Depth is predicted with monocular image, and is trained using self-supervised training method.