• Title/Summary/Keyword: cluster method

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Categorization of Traffic Type According to Seoul-City Administrative District Using Cluster Analysis (군집분석을 이용한 서울시 행정구역별 교통유형 분류)

  • Han, Mahn-Seob;Oh, Heung-Un
    • International Journal of Highway Engineering
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    • v.14 no.4
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    • pp.133-140
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    • 2012
  • PURPOSES : Traffic situation of Seoul City is different each administrative district. because each administrative district population, average travel speed, etc are different. thus, regionally differentiated policy is necessary. METHODS : In this study, first, it is to implement the cluster analysis using the traffic factor of twenty-five administrative districts in Seoul, categorize it into the cluster and understand the properties. second, related factors of speed were derived. and method to increase the speed was investigated. we choose the eleven traffic factors such as the number of traffic accident cases, total length, speed, the number of cross section, the number of cross section per km, the rate of roads, registered cars, population attending office and school, population density, area. RESULTS : In the results, first, we could categorize the Seoul-City administrative district into three clusters. in order to find Factors associated with speed a simple regression analysis was performed. and the number of intersections per km is closely related to the speed. CONCLUSIONS : Through this study, transportation policies reflecting local traffic-related characteristics are required.

Degrees of Freedom of Two-Cluster MIMO Multiway Relay Interference Channels Using Blind Interference Neutralization

  • Zhang, Bowei;Feng, Wenjiang;Dong, Tingting;Deng, Yina
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.1
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    • pp.168-186
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    • 2016
  • In this paper, we investigate the degrees of freedom (DoF) of a two-cluster multiple-input multiple-output (MIMO) multiway relay interference channel (mRIC), where there are two relays and two users per cluster. In this channel, users within the same cluster exchange messages among themselves with the help of two relays.We first obtain the DoF upper bound of the considered MIMO mRIC based on cut-set bound. Then, we propose a novel transmission strategy, blind interference neutralization (BIN), to approach the DoF upper bound. This new method utilizes the overheard information at two relays and focuses on the beamforming matrix designs at two relays so that the channel state information (CSI) at users is not required. Through theoretical analysis and numerical simulations, we show that the DoF upper bound can be obtained by using the BIN scheme. From simulation results, we show that the proposed BIN scheme can provide significant performance gain over the conventional time division multiple access (TDMA) scheme in terms of DoF. In addition, we show that the BIN scheme is a superior approach to the existing signal space alignment (SSA) schemes for the considered mRIC.

Recovery Management of Split-Brain Group in Highly Available Cluster file System $\textrm{SANique}^{TM}$ (고가용성 클러스터 파일 시스템 $\textrm{SANique}^{TM}$의 분할그룹 탐지 및 회복 기법)

  • 이규웅
    • Journal of Korea Multimedia Society
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    • v.7 no.4
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    • pp.505-517
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    • 2004
  • This paper overviews the design details of the cluster file system $\textrm{SANique}^{TM}$ on the SAN environment. $\textrm{SANique}^{TM}$ has the capability of transferring user data from shared SAN disk to client application without control of centralized file server. We, especially, focus on the characteristics and functions of recovery manager CRM of $\textrm{SANique}^{TM}$. The process component for failure detection and its overall procedure are described. We define the split-brain problem that cannot be easily detected in cluster file systems and also propose the recovery management method based on SAN disk in order to detect and solve the split-brain situation.

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Study on the Competitiveness Evaluation of Urban Cultural Tourism Creative Industry in Pan-Yangtze River Delta

  • Mengmeng, Shao
    • The Journal of Industrial Distribution & Business
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    • v.9 no.12
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    • pp.15-21
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    • 2018
  • Purpose - In order to improve the comprehensive competitiveness of cultural tourism creative industries in the region, different grade cities should adapt to local conditions and differentiated development as the angle. It can promote the optimization of regional tourism industry structure, and make relevant suggestions accordingly. Research design, data, and methodology - Based on the characteristics of cultural tourism creative industry, 24 indicators are selected from four aspects. The comprehensive competitiveness evaluation index system of cultural tourism creative industry is constructed. The essay use factor analysis to quantitatively evaluate 27 cities in the Pan-Yangtze River Delta, and use cluster analysis to classify the competitiveness of cultural tourism creative industries in each city into five types. Results - The results of cluster analysis show that the whole area presents five kinds of step-like features, which are mature leading type, the advantageous development type, comparatively advantageous type, well-grounded type and difference-promotion type. Conclusions - The factor analysis method was used to quantitatively evaluate 27 cities in the Pan-Yangtze River Delta, and cluster analysis was used to classify the cultural tourism creative industry competitiveness of each city into fives type city. Based on the differentiation of cultural tourism creative industry competitiveness and 27 cities in the Pan-Yangtze River Delta, the relevant strategies were proposed.

An Analysis on Water Pollution Degree by the Watershed considering Landcover Types in the Mid-Nakdong River (낙동강중류의 토지피복형태를 고려한 유역별 수질오염도 분석)

  • Lee, Woo-Sung;Jung, Sung-Gwan;Park, Kyung-Hun;You, Ju-Han
    • Journal of Environmental Science International
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    • v.15 no.4
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    • pp.349-357
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    • 2006
  • The purpose of this study is to evaluate the water pollution degree in the Mid-Nakdong River watershed regarding to landcover types using GIS method. As a result of landcover classification, rate of urban appeared highly on Daegu Metropolitan city. Also, rate of agriculture showed highly in the riparian zones of the Nakdong and Guemho River and rate of forest appeared highly in the borders of the study area. To identify the groups of watershed with similar landcover patterns using the Cluster Analysis. According to the cluster analysis, the fifty sub-watersheds were grouped in three clusters, 'Urban watershed', 'Agriculture watershed', 'Forest watershed'. The proportion of urban area in each cluster had a positive correlation with water pollution degree. Otherwise, the proportion of agriculture in the Agriculture watershed had a high positive correlation with water pollution degree. Therefore, it is necessary to estimate environmental capacity of water duality considering ecological and environmental characteristics of watershed ecosystem and expand water duality monitoring systems to small stream.

A Cluster Formation Scheme with Remaining Energy Level of Sensor Nodes in Wireless Sensor Networks (무선 센서 네트워크에서 잔여 에너지 레벨을 이용한 클러스터 형성 기법)

  • Jang, Kyung-Soo;Kangm, Jeong-Jin;Kouh, Hoon-Joon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.9 no.6
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    • pp.49-54
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    • 2009
  • Sensor nodes in wireless sensor networks operate in distributed environments with limited resources and sensing capabilities. Especially, a sensor node has a small energy. After the sensor nodes are distributed in some area, it is not accessible to the area. AIso, a battery of sensor node cannot change. One of the hot issues in wireless sensor networks maximizes the network lifetime through minimizing the energy dissipation of sensor nodes. In LEACH, the cluster head is elected based on a kind of probability method without considering remaining energy of sensor node. In this paper, we propose a cluster formation scheme that the network elect the node, which has higher energy level than average energy level of overall sensor network, as cluster head node. We show the superiority of our scheme through computer simulation.

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Lifetime Improvement of WSN by Optimizing Cluster Configuration (클러스터 구성 최적화를 통한 무선 센서 네트워크 수명 개선)

  • Lee, Jong-Yong
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.18 no.5
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    • pp.117-121
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    • 2018
  • A Wireless Sensor Network is a network that is composed of wireless sensor nodes. There is no restriction on the place where it can be installed because it is composed wirelessly. Instead, sensor nodes have limited energy, such as batteries. Therefore, to use the network for a long time, energy consumption should be minimized. Several protocols have been proposed to minimize energy consumption, and the typical protocol is the LEACH protocol. The LEACH protocol is a cluster-based protocol that minimizes energy consumption by dividing the sensor field into clusters. Depending on how you organize the clusters of sensor field, network lifetimes may increase or decrease. In this paper, we will improve the network lifetime by improving the cluster head selection method in LEACH Protocol.

Testing for Dust Stripping of Virgo Cluster Galaxies According to HI Gas Stripping Stage

  • Lee, Hye-Ran;Zabludoff, Ann;Lee, Joon Hyeop;Park, Byeong-Gon
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.75.2-75.2
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    • 2017
  • We Investigate dust stripping of Virgo cluster galaxies that are known to suffer HI gas stripping. The gas stripping phenomena of these galaxies may result from either ram pressure induced by the hot intracluster medium or gravitational tidal interactions between galaxies. While much efforts have been made to directly detect gas removed from cluster galaxies, the spatial distributions of dust, which should also be affected, are hardly known. Several previous studies have tried to directly detect the morphology of gas or dust using radio or infrared observations, but such approaches are hard to widely apply because of the limit of observational resolution and sensitivity. In this study, we try a different approach using optical data: measuring the background galaxy reddening by the dust stripped from the Virgo cluster members. Based on optical color excess maps of the background galaxies, we compare the ambient dust distribution with the HI morphology of the Virgo galaxies. We discuss how efficiently dust stripping can be detected with this method and how the stripped dust is associated with the removed gas according to HI gas stripping stage over the sample.

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The PC Clustering of the SIMD Structure for a Distributed Process of On-line Contingency (온라인 선로상정사고 분산처리를 위한 SIMD 구조의 PC 클러스터링)

  • Jang, Se-Hwan;Kim, Jin-Ho;Park, June-Ho
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.7
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    • pp.1150-1156
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    • 2008
  • This paper introduces the PC clustering of the SIMD structure for a distributed processing of on-line contingency to assess a static security of a power system. To execute on-line contingency analysis of a large-scale power system, we need to use high-speed execution device. Therefore, we constructed PC-cluster system using PC clustering method of the SIMD structure and applied to a power system, which relatively shows high quality on the high-speed execution and has a low price. SIMD(single instruction stream, multiple data stream) is a structure that processes are controlled by one signal. The PC cluster system is consisting of 8 PCs. Each PC employs the 2 GHz Pentium 4 CPU and is connected with the others through ethernet switch based fast ethernet. Also, we consider N-1 line contingency that have high potentiality of occurrence realistically. We propose the distributed process algorithm of the SIMD structure for reducing too much execution time on the on-line N-1 line contingency analysis in the large-scale power system. And we have verified a usefulness of the proposed algorithm and the constructed PC cluster system through IEEE 39 and 118 bus system.

A Strategy Through Segmentation Using Factor and Cluster Analysis: focusing on corporations having a special status (요인분석과 군집분석을 통한 세분화 및 전략방향 제시: 특수법인 사례를 중심으로)

  • Cho, Yong-Jun;Kim, Yeong-Hwa
    • The Korean Journal of Applied Statistics
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    • v.20 no.1
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    • pp.23-38
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    • 2007
  • Corporations adopt a segmentation depends on the existence of target variables, in general. In this paper, for the case of no target variables, a strategy through segmentation is proposed for corporations having a special status based on the management index. In case of segmentation using cluster analysis, however, if one classify according to many variables then he will be in face of difficulties in characterizing. Therefore, after extracting representative factors by factor analysis, a segmentation method through 2 step cluster analysis is employed on the basis of these representative factors. As a result, six segmentation groups are found and the resulting strategy is proposed which strengthens prominent factors and makes up defective factors for each group.