• Title/Summary/Keyword: 클러스터링 문제

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Design of the Fuzzy Traffic Controller by the Input-Output Data Clustering (입출력 데이터 클러스터링에 의한 퍼지 교통 제어기의 설계)

  • 지연상;최완규;이성주
    • Journal of the Korean Institute of Intelligent Systems
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    • v.11 no.3
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    • pp.241-245
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    • 2001
  • The existing fuzzy traffic controllers construct the rule-base based on the intuitive knowledge and experience or the standard rule-base, but the rule-base constructed by the above methods has difficulty in representing exactly and detailedly the control knowledge of the export and the operator. Therefore, in this paper, we propose a method that can improve the performance of the fuzzy traffic control by designing the fuzzy traffic controller which represents the control knowledge more exactly. The proposed method so modifies the position and shape of the fuzzy membership function based on the input-output data clustering that the fuzzy traffic controller can represent the control knowledge more exactly. Our method use the rough control knowledge based on intuitive knowledge and experience as the evaluation function for clustering the input-output data. The fuzzy traffic controller designed by the our method could represent the control knowledge of the expert and the operator more exactly, and it outperformed the existing controller in terms of the number of passed vehicles and the wasted green-time.

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Feature Selection of Fuzzy Pattern Classifier by using Fuzzy Mapping (퍼지 매핑을 이용한 퍼지 패턴 분류기의 Feature Selection)

  • Roh, Seok-Beom;Kim, Yong Soo;Ahn, Tae-Chon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.6
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    • pp.646-650
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    • 2014
  • In this paper, in order to avoid the deterioration of the pattern classification performance which results from the curse of dimensionality, we propose a new feature selection method. The newly proposed feature selection method is based on Fuzzy C-Means clustering algorithm which analyzes the data points to divide them into several clusters and the concept of a function with fuzzy numbers. When it comes to the concept of a function where independent variables are fuzzy numbers and a dependent variable is a label of class, a fuzzy number should be related to the only one class label. Therefore, a good feature is a independent variable of a function with fuzzy numbers. Under this assumption, we calculate the goodness of each feature to pattern classification problem. Finally, in order to evaluate the classification ability of the proposed pattern classifier, the machine learning data sets are used.

A Design of TNA(Traceback against Network Attacks) Based on Multihop Clustering using the depth of Tree structure on Ad-hoc Networks (애드혹 네트워크 상에 트리구조 깊이를 이용한 다중홉 클러스터링 기반 TNA(Traceback against Network Attacks) 설계)

  • Kim, Ju-Yung;Lee, Byung-Kwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37A no.9
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    • pp.772-779
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    • 2012
  • In the current MANET, DOS or DDOS attacks are increasing, but as MANET has limited bandwidth, computational resources and battery power, the existing traceback mechanisms can not be applied to it. Therefore, in case of traceback techniques being applied to MANET, the resource of each node must be used efficiently. However, in the traceback techniques applied to an existing ad hoc network, as a cluster head which represents all nodes in the cluster area manages the traceback, the overhead of the cluster head shortens each node's life. In addition, in case of multi-hop clustering, as one Cluster head manages more node than one, its problem is getting even worse. This paper proposes TNA(Traceback against Network Attacks) based on multihop clustering using the depth of tree structure in order to reduce the overhead of distributed information management.

Speech Recognition Performance Improvement using a convergence of GMM Phoneme Unit Parameter and Vocabulary Clustering (GMM 음소 단위 파라미터와 어휘 클러스터링을 융합한 음성 인식 성능 향상)

  • Oh, SangYeob
    • Journal of Convergence for Information Technology
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    • v.10 no.8
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    • pp.35-39
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    • 2020
  • DNN error is small compared to the conventional speech recognition system, DNN is difficult to parallel training, often the amount of calculations, and requires a large amount of data obtained. In this paper, we generate a phoneme unit to estimate the GMM parameters with each phoneme model parameters from the GMM to solve the problem efficiently. And it suggests ways to improve performance through clustering for a specific vocabulary to effectively apply them. To this end, using three types of word speech database was to have a DB build vocabulary model, the noise processing to extract feature with Warner filters were used in the speech recognition experiments. Results using the proposed method showed a 97.9% recognition rate in speech recognition. In this paper, additional studies are needed to improve the problems of improved over fitting.

The Shot Change Detection Using a Hybrid Clustering (하이브리드 클러스터링을 이용한 샷 전환 검출)

  • Lee, Ji-Hyun;Kang, Oh-Hyung;Na, Do-Won;Lee, Yang-Won
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.2
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    • pp.635-638
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    • 2005
  • The purpose of video segmentation is to segment video sequence into shots where each shot represents a sequence of frames having the same contents, and then select key frames from each shot for indexing. There are two types of shot changes, abrupt and gradual. The major problem of shot change detection lies on the difficulty of specifying the correct threshold, which determines the performance of shot change detection. As to the clustering approach, the right number of clusters is hard to be found. Different clustering may lead to completely different results. In this thesis, we propose a video segmentation method using a color-X$^2$ intensity histogram-based fuzzy c-means clustering algorithm.

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A Consolidated Wireless Internet Proxy Server Cluster Architecture (통합형 무선 인터넷 프록시 서버 클러스터 구조)

  • Kwak Hu-Keun;Chung Kyu-Sik
    • The KIPS Transactions:PartA
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    • v.13A no.3 s.100
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    • pp.231-240
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    • 2006
  • In this paper, wireless internet proxy server clusters are used for the wireless internet because their caching, distillation, and clustering functions are helpful to overcome the limitations and needs of the wireless internet. TranSend was proposed as a clustering based wireless internet proxy server but it has disadvantages; 1) its scalability is difficult to achieve because there is no systematic way to do it and 2) its structure is complex because of the inefficient communication structure among modules. In our former research, we proposed the CD-A structure which can be scalable in a systematic way but it also has disadvantages; its communication structure among modules is partly complex. In this paper, we proposed a consolidated scheme which has a systematic scalability and an efficient communication structure among modules. We performed experiments using 16 PCs and experimental results show 196% and 40% performance improvement of the proposed system compared to the TranSend and the CD-A system, respectively.

Development of Traffic State Classification Technique (교통상황 분류를 위한 클러스터링 기법 개발)

  • Woojin Kang;Youngho Kim
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.22 no.1
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    • pp.81-92
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    • 2023
  • Traffic state classification is crucial for time-of-day (TOD) traffic signal control. This paper proposed a traffic state classification technique applying Deep-Embedded Clustering (DEC) method that uses a high dimensional traffic data observed at all signalized intersections in a traffic signal control sub area (SA). So far, signal timing plan has been determined based on the traffic data observed at the critical intersection in SA. The current method has a limitation that it cannot consider a comprehensive traffic situation in SA. The proposed method alleviates the curse of dimensionality and turns out to overcome the shortcomings of the current signal timing plan.

Clustering Algorithm for Data Mining using Posterior Probability-based Information Entropy (데이터마이닝을 위한 사후확률 정보엔트로피 기반 군집화알고리즘)

  • Park, In-Kyoo
    • Journal of Digital Convergence
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    • v.12 no.12
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    • pp.293-301
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    • 2014
  • In this paper, we propose a new measure based on the confidence of Bayesian posterior probability so as to reduce unimportant information in the clustering process. Because the performance of clustering is up to selecting the important degree of attributes within the databases, the concept of information entropy is added to posterior probability for attributes discernibility. Hence, The same value of attributes in the confidence of the proposed measure is considerably much less due to the natural logarithm. Therefore posterior probability-based clustering algorithm selects the minimum of attribute reducts and improves the efficiency of clustering. Analysis of the validation of the proposed algorithms compared with others shows their discernibility as well as ability of clustering to handle uncertainty with ACME categorical data.

A Clustering Scheme Considering the Structural Similarity of Metadata in Smartphone Sensing System (스마트폰 센싱에서 메타데이터의 구조적 유사도를 고려한 클러스터링 기법)

  • Min, Hong;Heo, Junyoung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.6
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    • pp.229-234
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    • 2014
  • As association between sensor networks that collect environmental information by using numberous sensor nodes and smartphones that are equipped with various sensors, many applications understanding users' context have been developed to interact users and their environments. Collected data should be stored with XML formatted metadata containing semantic information to share the collected data. In case of distance based clustering schemes, the efficiency of data collection decreases because metadata files are extended and changed as the purpose of each system developer. In this paper, we proposed a clustering scheme considering the structural similarity of metadata to reduce clustering construction time and improve the similarity of metadata among member nodes in a cluster.

Temperature Control by On-line CFCM-based Adaptive Neuro-Fuzzy System (온 라인 CFCM 기반 적응 뉴로-퍼지 시스템에 의한 온도제어)

  • 윤기후;곽근창
    • Journal of the Institute of Electronics Engineers of Korea TE
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    • v.39 no.4
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    • pp.414-422
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    • 2002
  • In this paper, we propose a new method of adaptive neuro-fuzzy control using CFCM(Conditional Fuzzy c-means) clustering and fuzzy equalization method to deal with adaptive control problem. First, in the off-line design, CFCM clustering performs structure identification of adaptive neuro-fuzzy control with the homogeneous properties of the given input and output data. The parameter identification are established by hybrid learning using back-propagation algorithm and RLSE(Recursive Least Square Estimate). In the on-line design, the premise and consequent parameters are tuned to RLSE with forgetting factor due to a characteristic of time variant. Finally, we applied the proposed method to the water temperature control system and obtained better results than previous works such as fuzzy control.