• Title/Summary/Keyword: network optimization

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An intelligent optimization method for the HCSB blanket based on an improved multi-objective NSGA-III algorithm and an adaptive BP neural network

  • Wen Zhou;Guomin Sun;Shuichiro Miwa;Zihui Yang;Zhuang Li;Di Zhang;Jianye Wang
    • Nuclear Engineering and Technology
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    • v.55 no.9
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    • pp.3150-3163
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    • 2023
  • To improve the performance of blanket: maximizing the tritium breeding rate (TBR) for tritium self-sufficiency, and minimizing the Dose of backplate for radiation protection, most previous studies are based on manual corrections to adjust the blanket structure to achieve optimization design, but it is difficult to find an optimal structure and tends to be trapped by local optimizations as it involves multiphysics field design, which is also inefficient and time-consuming process. The artificial intelligence (AI) maybe is a potential method for the optimization design of the blanket. So, this paper aims to develop an intelligent optimization method based on an improved multi-objective NSGA-III algorithm and an adaptive BP neural network to solve these problems mentioned above. This method has been applied on optimizing the radial arrangement of a conceptual design of CFETR HCSB blanket. Finally, a series of optimal radial arrangements are obtained under the constraints that the temperature of each component of the blanket does not exceed the limit and the radial length remains unchanged, the efficiency of the blanket optimization design is significantly improved. This study will provide a clue and inspiration for the application of artificial intelligence technology in the optimization design of blanket.

Network Mobility Handoff Scheme to Support Fast Route Optimization in Nested Network Mobility (중첩된 이동 네트워크 환경에서 빠른 경로 최적화를 지원하는 핸드오프 방안)

  • Lee, Il-Ho;Lee, Jun-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.5
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    • pp.119-131
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    • 2009
  • Existing proposals on route optimization for nested Network Mobility(NEMO) have a problem that it is difficult to optimize a route promptly in an environment where a MR moves frequently. Also, they have L3 handoff latency as well as route optimization latency until an optimized route is formed. In this paper, we propose a L3 handoff scheme that supports fast route optimization for nested NEMO without any additional optimization procedure. To achieve this, our proposed scheme is designed to include a procedure that an AR acquires address informations of a MR. After receiving binding update message from the MR, the AR performs the binding update procedure with the MR's HA on behalf of the MR. Packets are delivered to the AR only passing by the MR's HA after a bi-directional tunnel is formed between the AR and the HA. The result of our performance evaluation has shown that the proposed scheme could provide excellent performance compared with the RRH and the ONEMO.

Performance Analysis of Neural Network on Determining The Optimal Stand Management Regimes (임분의 적정 시업체계분석을 위한 Neural Network 기법의 적용성 검토)

  • Chung, Joo Sang;Roise, Joseph P.
    • Journal of Korean Society of Forest Science
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    • v.84 no.1
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    • pp.63-70
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    • 1995
  • This paper discusses applications of neural network to stand stocking control problems. The scope of this research was to develop a neural network model for finding optimal stand management regimes and examining the performance of the model for field application. Performance was analyzed in consideration of the number of training examples and structural aspects of neural network. Research on network performance was based on extensive optimization studies for pure longleaf pine(Pinus palustris) stands. For experimental purposes. an existing nonlinear even-aged stand optimization model with a whole-stand growth and yield simulator was used to generate data samples required for the performance analysis.

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Introduction to a Novel Optimization Method : Artificial Immune Systems (새로운 최적화 기법 소개 : 인공면역시스템)

  • Yang, Byung-Hak
    • IE interfaces
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    • v.20 no.4
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    • pp.458-468
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    • 2007
  • Artificial immune systems (AIS) are one of natural computing inspired by the natural immune system. The fault detection, the pattern recognition, the system control and the optimization are major application area of artificial immune systems. This paper gives a concept of artificial immune systems and useful techniques as like the clonal selection, the immune network theory and the negative selection. A concise survey on the optimization problem based on artificial immune systems is generated. The overall performance of artificial immune systems for the optimization problem is discussed.

Analysis of Open-Source Hyperparameter Optimization Software Trends

  • Lee, Yo-Seob;Moon, Phil-Joo
    • International Journal of Advanced Culture Technology
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    • v.7 no.4
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    • pp.56-62
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    • 2019
  • Recently, research using artificial neural networks has further expanded the field of neural network optimization and automatic structuring from improving inference accuracy. The performance of the machine learning algorithm depends on how the hyperparameters are configured. Open-source hyperparameter optimization software can be an important step forward in improving the performance of machine learning algorithms. In this paper, we review open-source hyperparameter optimization softwares.

Max Flow Algorithm for the Network Flow Optimization (물류 유통을 최적화하기 위한 네트워크-유통 알고리즘)

  • Rhee, Chung-Sei;Jin, Ming-He
    • Convergence Security Journal
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    • v.8 no.3
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    • pp.65-71
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    • 2008
  • Network Flow has been playing important role in the modern industrial society. No matter what people or company run the network, both of them can't avoid circulating goods among the many branches. But in practical situations, not only the price rising in network increase the transportation costs, but the huge traffic flow volumes increase the transportation costs. Given to such a network environment, how to flow goods in the network is very important. In this paper, the MAX-Flow algorithm will be applied to network flow in order to maximize the network flow volumes. As far as the functions of network are correctly provided, the optimized network system always can make the flow process efficiently.

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Utility Bounds of Joint Congestion and Medium Access Control for CSMA based Wireless Networks

  • Wang, Tao;Yao, Zheng;Zhang, Baoxian;Li, Cheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.1
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    • pp.193-214
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    • 2017
  • In this paper, we study the problem of network utility maximization in a CSMA based multi-hop wireless network. Existing work in this aspect typically adopted continuous time Markov model for performance modelling, which fails to consider the channel conflict impact in actual CSMA networks. To maximize the utility of a CSMA based wireless network with channel conflict, in this paper, we first model its weighted network capacity (i.e., network capacity weighted by link queue length) and then propose a distributed link scheduling algorithm, called CSMA based Maximal-Weight Scheduling (C-MWS), to maximize the weighted network capacity. We derive the upper and lower bounds of network utility based on C-MWS. The derived bounds can help us to tune the C-MWS parameters for C-MWS to work in a distributed wireless network. Simulation results show that the joint optimization based on C-MWS can achieve near-optimal network utility when appropriate algorithm parameters are chosen and also show that the derived utility upper bound is very tight.

Genetic Optimization of Fuzzy C-Means Clustering-Based Fuzzy Neural Networks (FCM 기반 퍼지 뉴럴 네트워크의 진화론적 최적화)

  • Choi, Jeoung-Nae;Kim, Hyun-Ki;Oh, Sung-Kwun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.3
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    • pp.466-472
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    • 2008
  • The paper concerns Fuzzy C-Means clustering based fuzzy neural networks (FCM-FNN) and the optimization of the network is carried out by means of hierarchal fair competition-based parallel genetic algorithm (HFCPGA). FCM-FNN is the extended architecture of Radial Basis Function Neural Network (RBFNN). FCM algorithm is used to determine centers and widths of RBFs. In the proposed network, the membership functions of the premise part of fuzzy rules do not assume any explicit functional forms such as Gaussian, ellipsoidal, triangular, etc., so its resulting fitness values directly rely on the computation of the relevant distance between data points by means of FCM. Also, as the consequent part of fuzzy rules extracted by the FCM-FNN model, the order of four types of polynomials can be considered such as constant, linear, quadratic and modified quadratic. Since the performance of FCM-FNN is affected by some parameters of FCM-FNN such as a specific subset of input variables, fuzzification coefficient of FCM, the number of rules and the order of polynomials of consequent part of fuzzy rule, we need the structural as well as parametric optimization of the network. In this study, the HFCPGA which is a kind of multipopulation-based parallel genetic algorithms(PGA) is exploited to carry out the structural optimization of FCM-FNN. Moreover the HFCPGA is taken into consideration to avoid a premature convergence related to the optimization problems. The proposed model is demonstrated with the use of two representative numerical examples.

A Study on Automatic Learning of Weight Decay Neural Network (가중치감소 신경망의 자동학습에 관한 연구)

  • Hwang, Chang-Ha;Na, Eun-Young;Seok, Kyung-Ha
    • Journal of the Korean Data and Information Science Society
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    • v.12 no.2
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    • pp.1-10
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    • 2001
  • Neural networks we increasingly being seen as an addition to the statistics toolkit which should be considered alongside both classical and modern statistical methods. Neural networks are usually useful for classification and function estimation. In this paper we concentrate on function estimation using neural networks with weight decay factor The use of weight decay seems both to help the optimization process and to avoid overfitting. In this type of neural networks, the problem to decide the number of hidden nodes, weight decay parameter and iteration number of learning is very important. It is called the optimization of weight decay neural networks. In this paper we propose a automatic optimization based on genetic algorithms. Moreover, we compare the weight decay neural network automatically learned according to automatic optimization with ordinary neural network, projection pursuit regression and support vector machines.

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An Improved Coyote Optimization Algorithm-Based Clustering for Extending Network Lifetime in Wireless Sensor Networks

  • Venkatesh Sivaprakasam;Vartika Kulshrestha;Godlin Atlas Lawrence Livingston;Senthilnathan Arumugam
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.7
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    • pp.1873-1893
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    • 2023
  • The development of lightweight, low energy and small-sized sensors incorporated with the wireless networks has brought about a phenomenal growth of Wireless Sensor Networks (WSNs) in its different fields of applications. Moreover, the routing of data is crucial in a wide number of critical applications that includes ecosystem monitoring, military and disaster management. However, the time-delay, energy imbalance and minimized network lifetime are considered as the key problems faced during the process of data transmission. Furthermore, only when the functionality of cluster head selection is available in WSNs, it is possible to improve energy and network lifetime. Besides that, the task of cluster head selection is regarded as an NP-hard optimization problem that can be effectively modelled using hybrid metaheuristic approaches. Due to this reason, an Improved Coyote Optimization Algorithm-based Clustering Technique (ICOACT) is proposed for extending the lifetime for making efficient choices for cluster heads while maintaining a consistent balance between exploitation and exploration. The issue of premature convergence and its tendency of being trapped into the local optima in the Improved Coyote Optimization Algorithm (ICOA) through the selection of center solution is used for replacing the best solution in the search space during the clustering functionality. The simulation results of the proposed ICOACT confirmed its efficiency by increasing the number of alive nodes, the total number of clusters formed with the least amount of end-to-end delay and mean packet loss rate.