• 제목/요약/키워드: Unsupervised-learning

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개념 학습에 의한 신경 회로망 컴퓨터 (A Neural Network for Concept Learning : Recognitron)

  • 이기한;황희융;김춘석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1989년도 하계종합학술대회 논문집
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    • pp.495-499
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    • 1989
  • Concept is the set of selected neurons in a stable state of a neurel network. The Recognitron uses a parallel feedback structure to support concept learning. A number of clusters can exist in response to a given input, each of which make up a selective neuron. There are supervised and unsupervised learnig methods in concept teaming. In this paper, we have chosen unsupervised learning. Also, a new concept called relaxational learning has been introduced to stop runaway weights

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Neural Learning Algorithms for Independent Component Analysis

  • 최승진
    • 전기전자학회논문지
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    • 제2권1호
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    • pp.24-33
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    • 1998
  • Independent Component analysis (ICA) is a new statistical method for extracting statistically independent components from their linear instantaneous mixtures which are generated by an unknown linear generative model. The recognition model is learned in unsupervised manner so that the recovered signals by the recognition model become the possibly scaled estimates of original source signals. This paper addresses the neural learning approach to ICA. As recognition models a linear feedforward network and a linear feedback network are considered. Associated learning algorithms for both networks are derived from maximum likelihood and information-theoretic approaches, using natural Riemannian gradient [1]. Theoretical results are confirmed by extensive computer simulations.

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The principles of artificial intelligence and its applications in dentistry

  • Yoohyun Lee;Seung-Ho Ohk
    • International Journal of Oral Biology
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    • 제48권4호
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    • pp.45-49
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    • 2023
  • Digital dentistry has witnessed significant advancements in recent years, driven by extensive research following the introduction of cutting-edge technologies such as CAD/CAM and 3D oral scanners. Until now, 2D images obtained via x-ray or CT scans were critical to detect anomalies and for decision-making. This review describes the main principles and applications of supervised, unsupervised, and reinforcement learning in medical applications. In this context, we present a diverse range of artificial intelligence networks with potential applications in dentistry, accompanied by existing results in the field.

비감독 학습 기법에 의한 한국어의 키워드 추출 (Keyword Extraction in Korean Using Unsupervised Learning Method)

  • 신성윤;이양원
    • 한국정보통신학회논문지
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    • 제14권6호
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    • pp.1403-1408
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    • 2010
  • 한국어 정보검색에서는 문서를 대표하는 색인어 또는 키워드로서 명사를 사용하는데, 이러한 명사 및 키워드 추출이란 문서 내에 존재하는 모든 명사를 찾아내는 작업이다. 본 논문에서는 기 구축된 사전을 이용하여 키워드를 추출하는 방법을 제시한다. 이 방법은 불필요한 연산을 줄여서 수행 시간을 단축시켰다. 그리고 대용량의 문서에서도 정확도에 크게 영향을 미치지 않으면서 명사를 추출할 수 있다. 본 논문에서는 명사의 출현 특성을 이용한 명사추출 방법 및 비감독 학습 기법에 의한 키워드 추출 방법을 제시한다.

비지도 학습 기법을 사용한 RF 위협의 분포 분석 (Analysis on the Distribution of RF Threats Using Unsupervised Learning Techniques)

  • 김철표;노상욱;박소령
    • 한국군사과학기술학회지
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    • 제19권3호
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    • pp.346-355
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    • 2016
  • In this paper, we propose a method to analyze the clusters of RF threats emitting electrical signals based on collected signal variables in integrated electronic warfare environments. We first analyze the signal variables collected by an electronic warfare receiver, and construct a model based on variables showing the properties of threats. To visualize the distribution of RF threats and reversely identify them, we use k-means clustering algorithm and self-organizing map (SOM) algorithm, which are belonging to unsupervised learning techniques. Through the resulting model compiled by k-means clustering and SOM algorithms, the RF threats can be classified into one of the distribution of RF threats. In an experiment, we measure the accuracy of classification results using the algorithms, and verify the resulting model that could be used to visually recognize the distribution of RF threats.

비감독 학습 기법에 의한 키워드 추출 (Keyword Extraction Using Unsupervised Learning Method)

  • 신성윤;백정욱;이양원
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2010년도 춘계학술대회
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    • pp.165-166
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    • 2010
  • 명사 추출이란 문서 내에 존재하는 모든 명사를 찾아내는 작업으로서, 한국어 정보검색에서는 문서를 대표하는 색인어 또는 키워드로서 명사를 사용한다. 본 논문에서는 기 구축된 사전을 이용하여 키워드를 추출하는 방법을 제시한다. 이 방법은 불필요한 연산을 줄여서 수행 시간을 단축시켰다. 그리고 대용량의 문서에서도 정확도에 크게 영향을 미치지 않으면서 명사를 추출할 수 있다. 본 논문에서는 명사의 출현 특성을 이용한 명사 추출 방법 및 비감독 학습 기법에 의한 키워드 추출 방법을 제시한다.

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한의학 고문헌 텍스트 분석을 위한 비지도학습 기반 단어 추출 방법 비교 (Comparison of Word Extraction Methods Based on Unsupervised Learning for Analyzing East Asian Traditional Medicine Texts)

  • 오준호
    • 대한한의학원전학회지
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    • 제32권3호
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    • pp.47-57
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    • 2019
  • Objectives : We aim to assist in choosing an appropriate method for word extraction when analyzing East Asian Traditional Medical texts based on unsupervised learning. Methods : In order to assign ranks to substrings, we conducted a test using one method(BE:Branching Entropy) for exterior boundary value, three methods(CS:cohesion score, TS:t-score, SL:simple-ll) for interior boundary value, and six methods(BExSL, BExTS, BExCS, CSxTS, CSxSL, TSxSL) from combining them. Results : When Miss Rate(MR) was used as the criterion, the error was minimal when the TS and SL were used together, while the error was maximum when CS was used alone. When number of segmented texts was applied as weight value, the results were the best in the case of SL, and the worst in the case of BE alone. Conclusions : Unsupervised-Learning-Based Word Extraction is a method that can be used to analyze texts without a prepared set of vocabulary data. When using this method, SL or the combination of SL and TS could be considered primarily.

Decision support system for underground coal pillar stability using unsupervised and supervised machine learning approaches

  • Kamran, Muhammad;Shahani, Niaz Muhammad;Armaghani, Danial Jahed
    • Geomechanics and Engineering
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    • 제30권2호
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    • pp.107-121
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    • 2022
  • Coal pillar assessment is of broad importance to underground engineering structure, as the pillar failure can lead to enormous disasters. Because of the highly non-linear correlation between the pillar failure and its influential attributes, conventional forecasting techniques cannot generate accurate outcomes. To approximate the complex behavior of coal pillar, this paper elucidates a new idea to forecast the underground coal pillar stability using combined unsupervised-supervised learning. In order to build a database of the study, a total of 90 patterns of pillar cases were collected from authentic engineering structures. A state-of-the art feature depletion method, t-distribution symmetric neighbor embedding (t-SNE) has been employed to reduce significance of actual data features. Consequently, an unsupervised machine learning technique K-mean clustering was followed to reassign the t-SNE dimensionality reduced data in order to compute the relative class of coal pillar cases. Following that, the reassign dataset was divided into two parts: 70 percent for training dataset and 30 percent for testing dataset, respectively. The accuracy of the predicted data was then examined using support vector classifier (SVC) model performance measures such as precision, recall, and f1-score. As a result, the proposed model can be employed for properly predicting the pillar failure class in a variety of underground rock engineering projects.

일치성규칙과 목표값이 없는 데이터 증대를 이용하는 학습의 성능 향상 방법에 관한 연구 (A study on the performance improvement of learning based on consistency regularization and unlabeled data augmentation)

  • 김현웅;석경하
    • 응용통계연구
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    • 제34권2호
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    • pp.167-175
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    • 2021
  • 준지도학습(semi-supervised learning)은 목표값이 있는 데이터와 없는 데이터를 모두 이용하는 학습방법이다. 준지도학습에서 최근에 많은 관심을 받는 일치성규칙(consistency regularization)과 데이터 증대를 이용한 준지도학습(unsupervised data augmentation; UDA)은 목표값이 없는 데이터를 증대하여 학습에 이용한다. 그리고 성능 향상을 위해 훈련신호강화(training signal annealing; TSA)와 신뢰기반 마스킹(confidence based masking)을 이용한다. 본 연구에서는 UDA에서 사용하는 KL-정보량(Kullback-Leibler divergence)과 TSA 대신 JS-정보량(Jensen-Shanon divergene)과 역-TSA를 사용하고 신뢰기반 마스킹을 제거하는 방법을 제안한다. 실험을 통해 제안된 방법의 성능이 더 우수함을 보였다.

Decoding Brain States during Auditory Perception by Supervising Unsupervised Learning

  • Porbadnigk, Anne K.;Gornitz, Nico;Kloft, Marius;Muller, Klaus-Robert
    • Journal of Computing Science and Engineering
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    • 제7권2호
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    • pp.112-121
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    • 2013
  • The last years have seen a rise of interest in using electroencephalography-based brain computer interfacing methodology for investigating non-medical questions, beyond the purpose of communication and control. One of these novel applications is to examine how signal quality is being processed neurally, which is of particular interest for industry, besides providing neuroscientific insights. As for most behavioral experiments in the neurosciences, the assessment of a given stimulus by a subject is required. Based on an EEG study on speech quality of phonemes, we will first discuss the information contained in the neural correlate of this judgement. Typically, this is done by analyzing the data along behavioral responses/labels. However, participants in such complex experiments often guess at the threshold of perception. This leads to labels that are only partly correct, and oftentimes random, which is a problematic scenario for using supervised learning. Therefore, we propose a novel supervised-unsupervised learning scheme, which aims to differentiate true labels from random ones in a data-driven way. We show that this approach provides a more crisp view of the brain states that experimenters are looking for, besides discovering additional brain states to which the classical analysis is blind.