• Title/Summary/Keyword: and clustering

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Classification of Volatile Chemicals using Fuzzy Clustering Algorithm (퍼지 Clustering 알고리즘을 이용한 휘발성 화학물질의 분류)

  • Byun, Hyung-Gi;Kim, Kab-Il
    • Proceedings of the KIEE Conference
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    • 1996.07b
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    • pp.1042-1044
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    • 1996
  • The use of fuzzy theory in task of pattern recognition may be applicable gases and odours classification and recognition. This paper reports results obtained from fuzzy c-means algorithms to patterns generated by odour sensing system using an array of conducting polymer sensors, for volatile chemicals. For the volatile chemicals clustering problem, the three unsupervise fuzzy c-means algorithms were applied. From among the pattern clustering methods, the FCMAW algorithm, which updated the cluster centres more frequently, consistently outperformed. It has been confirmed as an outstanding clustering algorithm throughout experimental trials.

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Fast Super-Resolution Algorithm Based on Dictionary Size Reduction Using k-Means Clustering

  • Jeong, Shin-Cheol;Song, Byung-Cheol
    • ETRI Journal
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    • v.32 no.4
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    • pp.596-602
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    • 2010
  • This paper proposes a computationally efficient learning-based super-resolution algorithm using k-means clustering. Conventional learning-based super-resolution requires a huge dictionary for reliable performance, which brings about a tremendous memory cost as well as a burdensome matching computation. In order to overcome this problem, the proposed algorithm significantly reduces the size of the trained dictionary by properly clustering similar patches at the learning phase. Experimental results show that the proposed algorithm provides superior visual quality to the conventional algorithms, while needing much less computational complexity.

A Study of Similar Blog Recommendation System Using Termite Colony Algorithm (흰개미 군집 알고리즘을 이용한 유사 블로그 추천 시스템에 관한 연구)

  • Jeong, Gi Sung;Jo, I-Seok;Lee, Malrey
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.1
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    • pp.83-88
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    • 2013
  • This paper proposes a recommending system of the similar blogs gathered with similarities between blogs according to the similarity, dividing words, for each frequency, that individual blogs have. It improved the algorithm of k-means, using the model of the habits of white ants for better performance of clustering, and showed better performance of clustering as a result of evaluating and comparing with the existing algorithm of k-means as the improved algorithm. The recommending system of similar blog was designed and embodied, using the improved algorithm. TCA can reduce clustering time and the number of moving time for clustering compare with K-means algorithm.

Fuzzy Technique-based Identification of Close and Distant Clusters in Clustering

  • Lee, Kyung-Mi;Lee, Keon-Myung
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.11 no.3
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    • pp.165-170
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    • 2011
  • Due to advances in hardware performance, user-friendly interfaces are becoming one of the major concerns in information systems. Linguistic conversation is a very natural way of human communications. Fuzzy techniques have been employed to liaison the discrepancy between the qualitative linguistic terms and quantitative computerized data. This paper deals with linguistic queries using clustering results on data sets, which are intended to retrieve the close clusters or distant clusters from the clustering results. In order to support such queries, a fuzzy technique-based method is proposed. The method introduces distance membership functions, namely, close and distant membership functions which transform the metric distance between two objects into the degree of closeness or farness, respectively. In order to measure the degree of closeness or farness between two clusters, both cluster closeness measure and cluster farness measure which incorporate distance membership function and cluster memberships are considered. For the flexibility of clustering, fuzzy clusters are assumed to be formed. This allows us to linguistically query close or distant clusters by constructing fuzzy relation based on the measures.

The Alcock-Paczynski effect via clustering shells

  • Sabiu, Cristiano G.;Lee, Seokcheon;Park, Changbom
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.58.2-58.2
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    • 2013
  • Both peculiar velocities and errors in the assumed redshift-distance relation ("Alcock-Paczynski effect") generate correlations between clustering amplitude and orientation with respect to the line-of-sight. In this talk we propose a novel technique to extract the Alcock-Paczynski, geometric, distortion information from the anisotropic clustering of galaxies in 3-dimensional redshift space while minimizing non-linear clustering and peculiar velocity effects. We capitalize on the recent, large dataset from the Sloan Digital Sky Survey III (SDSS-III), which provides a large comoving sample of the universe out to high redshift. We focus our analysis on the Baryon Oscillation Spectroscopic Survey (BOSS) constant mass (CMASS) sample of 549,005 bright galaxies in the redshift range 0.43

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Speaker Adaptation Using i-Vector Based Clustering

  • Kim, Minsoo;Jang, Gil-Jin;Kim, Ji-Hwan;Lee, Minho
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.7
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    • pp.2785-2799
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    • 2020
  • We propose a novel speaker adaptation method using acoustic model clustering. The similarity of different speakers is defined by the cosine distance between their i-vectors (intermediate vectors), and various efficient clustering algorithms are applied to obtain a number of speaker subsets with different characteristics. The speaker-independent model is then retrained with the training data of the individual speaker subsets grouped by the clustering results, and an unknown speech is recognized by the retrained model of the closest cluster. The proposed method is applied to a large-scale speech recognition system implemented by a hybrid hidden Markov model and deep neural network framework. An experiment was conducted to evaluate the word error rates using Resource Management database. When the proposed speaker adaptation method using i-vector based clustering was applied, the performance, as compared to that of the conventional speaker-independent speech recognition model, was improved relatively by as much as 12.2% for the conventional fully neural network, and by as much as 10.5% for the bidirectional long short-term memory.

Clustering analysis and classification of cryptocurrency transaction using genetic algorithm (유전알고리즘을 이용한 암호화폐 거래정보의 군집화 분석 및 분류)

  • Park, Junhyung;Jeong, Seokhyeon;Park, Eunsik;Kim, Kyungsup;Won, Yoojae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2018.10a
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    • pp.22-26
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    • 2018
  • In this paper, we propose a model that classifies different transaction information by clustering and learning through similarity and transaction pattern of cryptocurrency transaction information. By using characteristics of genetic algorithms, we can get better clustering performance by eliminating unnecessary elements in clustering process. The transaction information including the clustering value is set as the training data, and the transaction information can be predicted through the classification algorithm. This can be used to automatically detect abnormal transactions from various transaction information of the cryptocurrency.

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Document Clustering using Term reweighting based on NMF (NMF 기반의 용어 가중치 재산정을 이용한 문서군집)

  • Lee, Ju-Hong;Park, Sun
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.4
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    • pp.11-18
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    • 2008
  • Document clustering is an important method for document analysis and is used in many different information retrieval applications. This paper proposes a new document clustering model using the re-weighted term based NMF(non-negative matrix factorization) to cluster documents relevant to a user's requirement. The proposed model uses the re-weighted term by using user feedback to reduce the gap between the user's requirement for document classification and the document clusters by means of machine. The Proposed method can improve the quality of document clustering because the re-weighted terms. the semantic feature matrix and the semantic variable matrix, which is used in document clustering, can represent an inherent structure of document set more well. The experimental results demonstrate appling the proposed method to document clustering methods achieves better performance than documents clustering methods.

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Variational Autoencoder Based Dimension Reduction and Clustering for Single-Cell RNA-seq Gene Expression (단일세포 RNA-SEQ의 유전자 발현 군집화를 위한 변이 자동인코더 기반의 차원감소와 군집화)

  • Chi, Sang-Mun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.11
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    • pp.1512-1518
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    • 2021
  • Since single cell RNA sequencing provides the expression profiles of individual cells, it provides higher cellular differential resolution than traditional bulk RNA sequencing. Using these single cell RNA sequencing data, clustering analysis is generally conducted to find cell types and understand high level biological processes. In order to effectively process the high-dimensional single cell RNA sequencing data fir the clustering analysis, this paper uses a variational autoencoder to transform a high dimensional data space into a lower dimensional latent space, expecting to produce a latent space that can give more accurate clustering results. By clustering the features in the transformed latent space, we compare the performance of various classical clustering methods for single cell RNA sequencing data. Experimental results demonstrate that the proposed framework outperforms many state-of-the-art methods under various clustering performance metrics.

A Study On Predicting Stock Prices Of Hallyu Content Companies Using Two-Stage k-Means Clustering (2단계 k-평균 군집화를 활용한 한류컨텐츠 기업 주가 예측 연구)

  • Kim, Jeong-Woo
    • Journal of the Korea Convergence Society
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    • v.12 no.7
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    • pp.169-179
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    • 2021
  • This study shows that the two-stage k-means clustering method can improve prediction performance by predicting the stock price, To this end, this study introduces the two-stage k-means clustering algorithm and tests the prediction performance through comparison with various machine learning techniques. It selects the cluster close to the prediction target obtained from the k-means clustering, and reapplies the k-means clustering method to the cluster to search for a cluster closer to the actual value. As a result, the predicted value of this method is shown to be closer to the actual stock price than the predicted values of other machine learning techniques. Furthermore, it shows a relatively stable predicted value despite the use of a relatively small cluster. Accordingly, this method can simultaneously improve the accuracy and stability of prediction, and it can be considered as the new clustering method useful for small data. In the future, developing the two-stage k-means clustering is required for the large-scale data application.