• 제목/요약/키워드: Networks

검색결과 22,120건 처리시간 0.038초

입자군집 최적화를 이용한 SVM 기반 다항식 뉴럴 네트워크 분류기 설계 (Design of SVM-Based Polynomial Neural Networks Classifier Using Particle Swarm Optimization)

  • 노석범;오성권
    • 전기학회논문지
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    • 제67권8호
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    • pp.1071-1079
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    • 2018
  • In this study, the design methodology as well as network architecture of Support Vector Machine based Polynomial Neural Network, which is a kind of the dynamically generated neural networks, is introduced. The Support Vector Machine based polynomial neural networks is given as a novel network architecture redesigned with the aid of polynomial neural networks and Support Vector Machine. The generic polynomial neural networks, whose nodes are made of polynomials, are dynamically generated in each layer-wise. The individual nodes of the support vector machine based polynomial neural networks is constructed as a support vector machine, and the nodes as well as layers of the support vector machine based polynomial neural networks are dynamically generated as like the generation process of the generic polynomial neural networks. Support vector machine is well known as a sort of robust pattern classifiers. In addition, in order to enhance the structural flexibility as well as the classification performance of the proposed classifier, multi-objective particle swarm optimization is used. In other words, the optimization algorithm leads to sequentially successive generation of each layer of support vector based polynomial neural networks. The bench mark data sets are used to demonstrate the pattern classification performance of the proposed classifiers through the comparison of the generalization ability of the proposed classifier with some already studied classifiers.

An Energy-Efficient Multicast Algorithm with Maximum Network Throughput in Multi-hop Wireless Networks

  • Jiang, Dingde;Xu, Zhengzheng;Li, Wenpan;Yao, Chunping;Lv, Zhihan;Li, Tao
    • Journal of Communications and Networks
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    • 제18권5호
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    • pp.713-724
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    • 2016
  • Energy consumption has become a main problem of sustainable development in communication networks and how to communicate with high energy efficiency is a significant topic that researchers and network operators commonly concern. In this paper, an energy-efficient multicast algorithm in multi-hop wireless networks is proposed aiming at new generation wireless communications. Traditional multi-hop wireless network design only considers either network efficiency or minimum energy consumption of networks, but rarely the maximum energy efficiency of networks. Different from previous methods, the paper targets maximizing energy efficiency of networks. In order to get optimal energy efficiency to build network multicast, our proposed method tries to maximize network throughput and minimize networks' energy consumption by exploiting network coding and sleeping scheme. Simulation results show that the proposed algorithm has better energy efficiency and performance improvements compared with existing methods.

신경회로망과 실험계획법을 이용한 타이어의 장력 추정 (Tension Estimation of Tire using Neural Networks and DOE)

  • 이동우;조석수
    • 한국정밀공학회지
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    • 제28권7호
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    • pp.814-820
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    • 2011
  • It takes long time in numerical simulation because structural design for tire requires the nonlinear material property. Neural networks has been widely studied to engineering design to reduce numerical computation time. The numbers of hidden layer, hidden layer neuron and training data have been considered as the structural design variables of neural networks. In application of neural networks to optimize design, there are a few studies about arrangement method of input layer neurons. To investigate the effect of input layer neuron arrangement on neural networks, the variables of tire contour design and tension in bead area were assigned to inputs and output for neural networks respectively. Design variables arrangement in input layer were determined by main effect analysis. The number of hidden layer, the number of hidden layer neuron and the number of training data and so on have been considered as the structural design variables of neural networks. In application to optimization design problem of neural networks, there are few studies about arrangement method of input layer neurons. To investigate the effect of arrangement of input neurons on neural network learning tire contour design parameters and tension in bead area were assigned to neural input and output respectively. Design variables arrangement in input layer was determined by main effect analysis.

사설망 인터페이스에서 토폴로지 요약 테스트를 위한 시뮬레이터 설계 구현 및 TA 알고리즘 성능분석 (Design and Implementation of Simulator for Topology Aggregation in Private Networks to Networks Interface and Performance Analysis of TA Algorithms)

  • 김남희;김변곤;서혜영;박기홍
    • 한국콘텐츠학회논문지
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    • 제7권5호
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    • pp.1-9
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    • 2007
  • 토폴로지 정보는 망에서 계층적으로 구성될 수 있으며, 토폴로지 정보를 요약하는 과정을 토폴로지 요약이라 한다. 이는 라우팅과 네트워크의 확장성에 매우 중요한 요소이다. 특히, 사설망 인터페이스에서 라우팅 알고리즘과 토폴로지 요약 알고리즘은 네트워크의 성능에 중요한 변수가 된다. 따라서 본 논문에서는 사설망 인터페이스에서 토폴로지 요약을 위한 라우팅 시뮬레이터를 설계 및 구현하였다. 그리고 구현된 시뮬레이터를 사용하여 기존 토폴로지 요약 알고리즘의 성능을 분석하였다. 구현된 사설망 인터페이스 시뮬레이터는 토폴로지 요약 알고리즘 개발에 유용하게 사용될 수 있다.

Handover Control for WCDMA Femtocell Networks

  • Chowdhury, Mostafa Zaman;Jang, Yeong-Min
    • 한국통신학회논문지
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    • 제35권5B호
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    • pp.741-752
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    • 2010
  • The ability to seamlessly switch between the macro networks and femtocell networks is a key driver for femtocell network deployment. The handover procedures for the integrated femtocell/macrocell networks differ from the existing handovers. Some modifications of existing network and protocol architecture for the integration of femtocell networks with the existing macrocell networks are also essential. These modifications change the signal flow for handover procedures due to different 2-tier cell (macrocell and femtocell) environment. The handover between two networks should be performed with minimum signaling. A frequent and unnecessary handover is another problem for hierarchical femtocell/macrocell network environment that must be minimized. This work studies the details mobility management schemes for small and medium scale femtocell network deployment. To do that, firstly we present two different network architectures for small scale and medium scale WCDMA femtocell deployment. The details handover call flow for these two network architectures and CAC scheme to minimize the unnecessary handovers are proposed for the integrated femtocell/macrocell networks. The numerical analysis for the proposed M/M/N/N queuing scheme and the simulation results of the proposed CAC scheme demonstrate the handover call control performances for femtocell environment.

중년기 남성의 사회관계망과 심리적 복지감 (A Study on Social Networks and Psychological Well-being of Middle-aged Men)

  • 이기숙;김현지
    • 대한가정학회지
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    • 제40권6호
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    • pp.133-144
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    • 2002
  • The purpose of this study was to investigate the characteristics of the social networks and its relationship with the psychological well-being of middle-aged men. The participants were 314 men who were married living in Pusan, aged between 40 and 59, having occupation and children. Data were collected by questionnaire which consists of Social Networks Scale and Psychological Well-being Scale. The major results of the study were summarized as follows; First, the range of the social contact with men's own kin was wider than women's. In the contact frequency of midge-aged men, primary networks were shown more frequent contact than the secondary networks. In the characteristics of interactive function of social networks, kinship of the middle- aged men, their partners and friendship networks were the most important among the six networks, which agrees the fact that kin are still the primary source of social support. Second, the level of psychological well-being was lower than family-related satisfaction and work-related satisfaction. In the work-related satisfaction, the level of job satisfaction was lower than the other sub-categories. Psychological well-being of middle-aged men were affected by Social economic status as well.

Formalizing the Design, Evaluation, and Analysis of Quality of Protection in Wireless Networks

  • Lim, Sun-Hee;Yun, Seung-Hwan;Lim, Jong-In;Yi, Ok-Yeon
    • Journal of Communications and Networks
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    • 제11권6호
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    • pp.634-644
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    • 2009
  • A diversity of wireless networks, with rapidly evolving wireless technology, are currently in service. Due to their innate physical layer vulnerability, wireless networks require enhanced security components. WLAN, WiBro, and UMTS have defined proper security components that meet standard security requirements. Extensive research has been conducted to enhance the security of individual wireless platforms, and we now have meaningful results at hand. However, with the advent of ubiquitous service, new horizontal platform service models with vertical crosslayer security are expected to be proposed. Research on synchronized security service and interoperability in a heterogeneous environment must be conducted. In heterogeneous environments, to design the balanced security components, quantitative evaluation model of security policy in wireless networks is required. To design appropriate evaluation method of security policies in heterogeneous wireless networks, we formalize the security properties in wireless networks. As the benefit of security protocols is indicated by the quality of protection (QoP), we improve the QoP model and evaluate hybrid security policy in heterogeneous wireless networks by applying to the QoP model. Deriving relative indicators from the positive impact of security points, and using these indicators to quantify a total reward function, this paper will help to assure the appropriate benchmark for combined security components in wireless networks.

On the Formulation and Optimal Solution of the Rate Control Problem in Wireless Mesh Networks

  • Le, Cong Loi;Hwang, Won-Joo
    • 한국통신학회논문지
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    • 제32권5B호
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    • pp.295-303
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    • 2007
  • An algorithm is proposed to seek a local optimal solution of the network utility maximization problem in a wireless mesh network, where the architecture being considered is an infrastructure/backbone wireless mesh network. The objective is to achieve proportional fairness amongst the end-to-end flows in wireless mesh networks. In order to establish the communication constraints of the flow rates in the network utility maximization problem, we have presented necessary and sufficient conditions for the achievability of the flow rates. Since wireless mesh networks are generally considered as a type of ad hoc networks, similarly as in wireless multi-hop network, the network utility maximization problem in wireless mesh network is a nonlinear nonconvex programming problem. Besides, the gateway/bridge functionalities in mesh routers enable the integration of wireless mesh networks with various existing wireless networks. Thus, the rate optimization problem in wireless mesh networks is more complex than in wireless multi-hop networks.

Spiking Neural Networks(SNN) 구조에서 뉴런의 개수와 학습량에 따른 학습 성능 변화 분석 (An analysis of learning performance changes in spiking neural networks(SNN))

  • 김용주;김태호
    • 문화기술의 융합
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    • 제6권3호
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    • pp.463-468
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    • 2020
  • 인공지능 연구는 다양한 분야에 적용되며 발전하고 있다. 본 논문에서는 차세대 인공지능 연구 분야인 SNN(Spiking Neural Networks) 형태의 인공지능 구현 방식을 사용하여 신경망을 구축하고, 그 신경망에서 뉴런의 개수가 신경망의 성능에 어떠한 영향을 미치는지를 분석한다. 또한 신경망 학습량을 증가시키면서 신경망의 성능이 어떻게 바뀌는지를 분석한다. 해당 연구 결과를 통해 각 분야에서 사용되는 SNN 기반의 신경망을 최적화 할 수 있을 것이다.

A New Roaming Authentication Framework For Wireless Communication

  • Li, Xiaowei;Zhang, Yuqing;Liu, Xuefeng;Cao, Jin;Zhao, Qianqian
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권8호
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    • pp.2061-2080
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    • 2013
  • Roaming authentication protocol is widely used in wireless network which can enable a seamless service for the mobile users. However, the classical approach requires the home server's participation during the authentication between the mobile user and the foreign server. So the more the roaming requests are performed the heavier burden will be on the home server. In this paper, we propose a new roaming authentication framework for wireless communication without the home server's participation. The new roaming authentication protocol in the new framework takes advantage of the ID-based cryptography and provides user anonymity. It has good performance compared with the roaming authentication protocols whose authentication do not need the home server's participation in terms of security and computation costs. Moreover, a new User-to-User authentication protocol in the new framework is also present. All the authentications proposed in this paper can be regarded as a common construction and can be applied to various kinds of wireless networks such as Cellular Networks, Wireless Mesh Networks and Vehicle Networks.