• Title/Summary/Keyword: cluster method

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A Fuzzy Rule Extraction by EM Algorithm and A Design of Temperature Control System (EM 알고리즘에 의한 퍼지 규칙생성과 온도 제어 시스템의 설계)

  • 오범진;곽근창;유정웅
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.16 no.5
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    • pp.104-111
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    • 2002
  • This paper presents a fuzzy rule extraction method using EM(Expectation-Maximization) algorithm and a design method of adaptive neuro-fuzzy control. EM algorithm is used to estimate a maximum likelihood of a GMM(Gaussian Mixture Model) and cluster centers. The estimated clusters is used to automatically construct the fuzzy rules and membership functions for ANFIS(Adaptive Neuro-Fuzzy Inference System). Finally, we applied the proposed method to the water temperature control system and obtained better results with respect to the number of rules and SAE(Sum of Absolute Error) than previous techniques such as conventional fuzzy controller.

An Empirical Study on the Distribution Park Strategy for Logistics-Hub in Northeast Asia (동북아 물류거점화를 위한 항만배후부지 구축전략에 관한 실증연구)

  • Yoon Byeong-Goo;Kwak Kyu-Seok;Ahn Ki-Myung;Kim Myung-Jae
    • Journal of Navigation and Port Research
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    • v.29 no.10 s.106
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    • pp.897-906
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    • 2005
  • The purpose of this research is to verify the strategic fitness and relevance of the distribution park for a hub port in Northeast Asia and to find a method to be a hub-port with a competitive edge. The strategic factor of distribution park development are policy, methodology and promotion method So these factors are analysed by structural equation model. The essential results of the research show that distribution park should be actually developed to produce value-added and to be port cluster.

A Study on the Structural Model and Evaluation of National Maritime Power System(I) (국가해양력시스템의 구조모델과 평가에 관한 연구(I))

  • 임봉택;이철영
    • Journal of Korean Port Research
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    • v.14 no.1
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    • pp.57-64
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    • 2000
  • For composing the structure model of national maritime power system by system structural modeling, in this study, the 50 basic factors are selected by survey of the extensive and through literatures on maritime, sea, maritime power and sea power. And the basic factors are classified into 36 component factors by cluster method. The 9 attributes are extracted by the application of the principle component analysis method, one of the factor analysis method in system engineering, to component factors. In this study, we define the attributes composing the national maritime power system by integrating the result of this study and existed our studies relating to this topic. Which are showed in Table 2. and we show the structure model of national maritime power system in Fig. 3. In Table 2, the 9 attributes are as follows : the fundamental power of maritime, shipping and port power, naval power, fishing power, shipbuilding power, the power of ocean research and development, dependency on seaborne trade, the protection power of ocean environment and the will and inclination of govemment. Also, in the case of evaluating this system, we conform the importance of considering the interactions among the attributes which have strong interactions in structure model of national maritime power system.

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P2P Ranging-Based Cooperative Localization Method for a Cluster of Mobile Nodes Containing IR-UWB PHY

  • Cho, Seong Yun;Kim, Joo Young;Enkhtur, Munkhzul
    • ETRI Journal
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    • v.35 no.6
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    • pp.1084-1093
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    • 2013
  • problem of pedestrian localization using mobile nodes containing impulse radio ultra wideband (IR-UWB) is considered. IEEE 802.15.4a-based IR-UWB can achieve accurate ranging. However, the coverage is as short as 30 m, owing to the restricted transmit power. This factor may cause a poor geometric relationship among the mobile nodes and anchor nodes in certain environments. To localize a group of pedestrians accurately, an enhanced cooperative localization method is proposed. We describe a sequential algorithm and define problems that may occur in the implementation of the algorithm. To solve these problems, a batch algorithm is proposed. The batch algorithm can be carried out after performing the sequential algorithm to linearize the nonlinear range equation. When a sequential algorithm cannot be performed due to a poor geometric relationship among nodes, a batch algorithm can be carried out directly. Herein, Monte Carlo simulations are presented to illustrate the proposed method and verify its performance.

Studies on the Optimization of Contact Oxide Etching Process Using Taguchi Method (Taguchi 방법을 사용한 콘택 산호막 식각 공정 최적화 연구)

  • Jeon, Yeong-Jin;Kim, Chang-Il;Gu, Jin-Geun;Yu, Hyeong-Jun
    • Korean Journal of Materials Research
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    • v.5 no.1
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    • pp.63-74
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    • 1995
  • Process optimization experiments based on the Taguchi method were performed in order to set up the optimal process conditions for the contact oxide etching process module which was built in order to be attached to the cluster system of multi-processing purpose. From the two times experiments of Taguchi method, the overall behaviors of the etchmg characteristics depending upon the equipment parameters were understood at the 1st Taguchi experiment, the detail and optimal process conditions were extracted from the 2nd Taguchi experiment. As a final analysis of experimental results, the optimal etching characteristics were obtalned at the process conditions of $CHF_{3}/CF_{4}$ gas flow rate=72/8 sccm, chamber pressure=50 mTorr, RF power=300 Watts, magnetic field intensity=90 Gauss.

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Post-Processing for JPEG-Coded Image Deblocking via Sparse Representation and Adaptive Residual Threshold

  • Wang, Liping;Zhou, Xiao;Wang, Chengyou;Jiang, Baochen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.3
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    • pp.1700-1721
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    • 2017
  • The problem of blocking artifacts is very common in block-based image and video compression, especially at very low bit rates. In this paper, we propose a post-processing method for JPEG-coded image deblocking via sparse representation and adaptive residual threshold. This method includes three steps. First, we obtain the dictionary by online dictionary learning and the compressed images. The dictionary is then modified by the histogram of oriented gradient (HOG) feature descriptor and K-means cluster. Second, an adaptive residual threshold for orthogonal matching pursuit (OMP) is proposed and used for sparse coding by combining blind image blocking assessment. At last, to take advantage of human visual system (HVS), the edge regions of the obtained deblocked image can be further modified by the edge regions of the compressed image. The experimental results show that our proposed method can keep the image more texture and edge information while reducing the image blocking artifacts.

An Empirical Study on the Distribution Park Strategy for Northeast Asia Logistics-Hub (동북아(東北亞) 물류거점화(物流據點化)를 위한 항만배후부지(港灣背後敷地) 구축전략(構築戰略)에 관(關)한 실증연구(實證硏究))

  • Yun, Byeong-Goo;Kwak, Kyu-Seok;Ahn, Ki-Myung
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.29 no.1
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    • pp.465-470
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    • 2005
  • The purpose of this research is to verify the strategic fitness and relevance of the distribution park for hub port in Northeast Asia and to find a method to be a hub-port with a competitive edge. The Strategic factor of distribution park development are policy, methodology and promotion method. So these factors are analysed by structural equation model. The essential results of the research show that distribution park should be actually developed to product value-added and connected to industry park to be port cluster.

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Segmentation of Color Image by Subtractive and Gravity Fuzzy C-means Clustering (차감 및 중력 fuzzy C-means 클러스터링을 이용한 칼라 영상 분할에 관한 연구)

  • Jin, Young-Goun;Kim, Tae-Gyun
    • Journal of IKEEE
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    • v.1 no.1 s.1
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    • pp.93-100
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    • 1997
  • In general, fuzzy C-means clustering method was used on the segmentation of true color image. However, this method requires number of clusters as an input. In this study, we suggest new method that uses subtractive and gravity fuzzy C-means clustering. We get number of clusters and initial cluster centers by applying subtractive clustering on color image. After coarse segmentation of the image, we apply gravity fuzzy C-means for optimizing segmentation of the image. We show efficiency of the proposed algorithm by qualitative evaluation.

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A CLB based CPLD Low-power Technology Mapping Algorithm consider Area and Delay time (면적과 지연 시간을 고려한 CLB 구조의 CPLD 저전력 기술 매핑 알고리즘)

  • 김재진;조남경;전종식;김희석
    • Proceedings of the IEEK Conference
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    • 2003.07b
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    • pp.1169-1172
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    • 2003
  • In this paper, a CLB-based CPLD low-power technology mapping algorithm consider area and delay time is proposed. To perform low power technology mapping for CPLD, a given Boolean network have to be represented to DAG. The proposed algorithm are consist of three step. In the first step, TD(Transition Density) calculation have to be performed. In the second step, the feasible clusters are generated by considering the following conditions: the number of output, the number of input and the number of OR-terms for CLB(Common Logic Block) within a CPLD. The common node cluster merging method, the node separation method, and the node duplication method are used to produce the feasible clusters. In the final step, low power technology mapping based on the CLBs is packing the feasible clusters into the several proper CLBs. The proposed algorithm is examined by using benchmarks in SIS. In the case of that the number of OR-terms is 5, the experiments results show that reduce the power consumption by 30.73% comparing with that of TEMPLA, and 17.11% comparing with that of PLAmap respectively.

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A Study on the Development of a Cantilever & Swing-Type Fast Tool Servo with Rotational Moment Hinge Design (회전모멘트 힌지 설계에 따른 캔틸레버형 횡방향 구동 Fast Tool Servo 연구 개발에 관한 고찰)

  • Lee, Seung Jun;Jeong, Jae Ho
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.19 no.8
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    • pp.43-49
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    • 2020
  • The growth of the AR/VR market due to the advent of the 4th Industrial Revolution begins with the development of the display industry. The development of OLED and flexible displays is further accelerated by the development of R2R technology. Micro-processing technology using a fast tool servo (FTS), the core technology in R2R processes, is making technological progress in increasingly diverse ways. This paper proposes a method to develop an FTS for horizontal driving and presents this method through experiments and analyses. To develop a swing-type FTS based on a seesaw motion, a rotational moment hinge structure was designed for each type, and research was conducted to determine an effective design method. A cantilever-based swing-type FTS was developed in two variations: one with single-side hinges and another with dual-side hinges. The parameters in the design of the swing-type FTS are rotational moment, natural frequency, and material selection. In conclusion, an FTS with a single-side hinge demonstrates the high performance required for micro processing.