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基于Space P和K-means的货运航司航线网络特征分析研究
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作者 罗凤娥 卫昌波 +1 位作者 韩晓彤 郭玲玉 《现代电子技术》 北大核心 2026年第1期102-107,共6页
针对航空货运行业的迅速扩张,航空货运网络结构变得更加复杂,文中通过Space P建模方法构建了货运航空公司航线网络模型,并运用K-means聚类算法对网络进行了深入分析。选取度、平均路径长度、聚类系数和中间度等关键网络特性指标对航线... 针对航空货运行业的迅速扩张,航空货运网络结构变得更加复杂,文中通过Space P建模方法构建了货运航空公司航线网络模型,并运用K-means聚类算法对网络进行了深入分析。选取度、平均路径长度、聚类系数和中间度等关键网络特性指标对航线网络进行层次化分类,揭示了网络的复杂特征和层次结构。通过仿真实验评估了网络的小世界特性,并利用轮廓系数得到不同K值下的聚类结果,进而确定最优聚类结果。同时,模拟了航线网络在遭受攻击时的鲁棒性,实验结果表明:在航线网络较为脆弱的情况下,该方法为货运航司航线网络的优化和抗风险能力的提升提供了重要参考。 展开更多
关键词 航空货运 space P 航线网络 复杂网络 聚类算法 网络特征
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Indoor space layout research based on redirection algorithm
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作者 Qizhao WANG 《虚拟现实与智能硬件(中英文)》 2025年第6期618-638,共21页
Background Advancements in computer science and knowledge have made the incorporation of control theory,graphics processing,and mathematical models increasingly important for urban design planning.However,challenges r... Background Advancements in computer science and knowledge have made the incorporation of control theory,graphics processing,and mathematical models increasingly important for urban design planning.However,challenges remain in aligning virtual reality(VR)environments with real-world spatial and preparation requirements,particularly in indoor urban spaces.Methods This study investigates the application of VR technology to urban design,focusing on the growth and assessment of the redirection of the space-tree sorter algorithm(STSA).It outlines various assessment indicators,organization of the VR-based system architecture,and construction of 3D urban models and databases.This research also examined methods for the interactive adjustment of indoor space layout plans within a VR environment.Results This research study involved developing and demonstrating the creation and simulation of urban indoor spaces and cityscapes in VR and implementing an experimental setup to test layout modifications and system interactivity.The results indicated enhanced alignment between the virtual and physical spatial configurations.The analysis highlights the strengths and limitations of current VR systems for urban design and identifies key areas for optimization and refinement.Conclusion High congruence between virtual simulations and real-world urban spaces is necessary for effective VR-driven urban planning.This study contributes to a clearer understanding of how 3D modeling,interactive layout design,and reproduction technology can be efficiently employed to support urban increase initiatives. 展开更多
关键词 Virtual reality(VR) Indoor space layout 3D visualization space-Trek Sorter algorithm Redirection algorithm
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Calculation algorithm for the space charge force of a train with infinite bunches
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作者 San-Hai Ren Hong-Yu Li +5 位作者 Jia-Ru Shi Hao Zha Wei-Hang Gu Qiang Gao Qian Tan Huai-Bi Chen 《Nuclear Science and Techniques》 2025年第6期13-25,共13页
Industrial linear accelerators often contain many bunches when their pulse widths are extended to microseconds.As they typically operate at low electron energies and high currents,the interactions among bunches cannot... Industrial linear accelerators often contain many bunches when their pulse widths are extended to microseconds.As they typically operate at low electron energies and high currents,the interactions among bunches cannot be neglected.In this study,an algorithm is introduced for calculating the space charge force of a train with infinite bunches.By utilizing the ring charge model and the particle-in-cell(PIC)method and combining analytical and numerical methods,the proposed algorithm efficiently calculates the space charge force of infinite bunches,enabling the accurate design of accelerator parameters and a comprehensive understanding of the space charge force.This is a significant improvement on existing simulation software such as ASTRA and PARMELA that can only handle a single bunch or a small number of bunches.The PIC algorithm is validated in long drift space transport by comparing it with existing models,such as the infinite-bunch,ASTRA single-bunch,and PARMELA several-bunch algorithms.The space charge force calculation results for the external acceleration field are also verified.The reliability of the proposed algorithm provides a foundation for the design and optimization of industrial accelerators. 展开更多
关键词 Particle-in-cell method space charge force algorithm Infinite bunches
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Weighted adaptive filtering algorithm for carrier tracking of deep space signal 被引量:8
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作者 Song Qingping Liu Rongke 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第4期1236-1244,共9页
Carrier tracking is laid great emphasis and is the difficulty of signal processing in deep space communication system.For the autonomous radio receiving system in deep space, the tracking of the received signal is aut... Carrier tracking is laid great emphasis and is the difficulty of signal processing in deep space communication system.For the autonomous radio receiving system in deep space, the tracking of the received signal is automatic when the signal to noise ratio(SNR) is unknown.If the frequency-locked loop(FLL) or the phase-locked loop(PLL) with fixed loop bandwidth, or Kalman filter with fixed noise variance is adopted, the accretion of estimation error and filter divergence may be caused.Therefore, the Kalman filter algorithm with adaptive capability is adopted to suppress filter divergence.Through analyzing the inadequacies of Sage–Husa adaptive filtering algorithm, this paper introduces a weighted adaptive filtering algorithm for autonomous radio.The introduced algorithm may resolve the defect of Sage–Husa adaptive filtering algorithm that the noise covariance matrix is negative definite in filtering process.In addition, the upper diagonal(UD) factorization and innovation adaptive control are used to reduce model estimation errors,suppress filter divergence and improve filtering accuracy.The simulation results indicate that compared with the Sage–Husa adaptive filtering algorithm, this algorithm has better capability to adapt to the loop, convergence performance and tracking accuracy, which contributes to the effective and accurate carrier tracking in low SNR environment, showing a better application prospect. 展开更多
关键词 Adaptive algorithms Carrier tracking Deep space communicationKalman filters Tracking accuracy WEIGHTED
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An adaptive ant colony system algorithm for continuous-space optimization problems 被引量:20
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作者 李艳君 吴铁军 《Journal of Zhejiang University Science》 CSCD 2003年第1期40-46,共7页
Ant colony algorithms comprise a novel category of evolutionary computation methods for optimization problems, especially for sequencing-type combinatorial optimization problems. An adaptive ant colony algorithm is pr... Ant colony algorithms comprise a novel category of evolutionary computation methods for optimization problems, especially for sequencing-type combinatorial optimization problems. An adaptive ant colony algorithm is proposed in this paper to tackle continuous-space optimization problems, using a new objective-function-based heuristic pheromone assignment approach for pheromone update to filtrate solution candidates.Global optimal solutions can be reached more rapidly by self-adjusting the path searching behaviors of the ants according to objective values. The performance of the proposed algorithm is compared with a basic ant colony algorithm and a Square Quadratic Programming approach in solving two benchmark problems with multiple extremes. The results indicated that the efficiency and reliability of the proposed algorithm were greatly improved. 展开更多
关键词 Ant colony algorithm Continuous space optimization Pheromone update strategy
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N4SID and MOESP Algorithms to Highlight the Ill-conditioning into Subspace Identification 被引量:4
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作者 Slim Hachicha Maher Kharrat Abdessattar Chaari 《International Journal of Automation and computing》 EI CSCD 2014年第1期30-38,共9页
In this paper,an analysis for ill conditioning problem in subspace identifcation method is provided.The subspace identifcation technique presents a satisfactory robustness in the parameter estimation of process model ... In this paper,an analysis for ill conditioning problem in subspace identifcation method is provided.The subspace identifcation technique presents a satisfactory robustness in the parameter estimation of process model which performs control.As a frst step,the main geometric and mathematical tools used in subspace identifcation are briefly presented.In the second step,the problem of analyzing ill-conditioning matrices in the subspace identifcation method is considered.To illustrate this situation,a simulation study of an example is introduced to show the ill-conditioning in subspace identifcation.Algorithms numerical subspace state space system identifcation(N4SID)and multivariable output error state space model identifcation(MOESP)are considered to study,the parameters estimation while using the induction motor model,in simulation(Matlab environment).Finally,we show the inadequacy of the oblique projection and validate the efectiveness of the orthogonal projection approach which is needed in ill-conditioning;a real application dealing with induction motor parameters estimation has been experimented.The obtained results proved that the algorithm based on orthogonal projection MOESP,overcomes the situation of ill-conditioning in the Hankel s block,and thereby improving the estimation of parameters. 展开更多
关键词 Subspace identification ILL-CONDITIONING oblique projection orthogonal projection algorithms numerical subspace state space system identification (N4SID) multivariable output error state space model identification (MOESP) induction motor
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Gaussian fitting based optimal design of aircraft mission success space using multi-objective genetic algorithm 被引量:4
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作者 Yuan GAO Yongliang TIAN +1 位作者 Hu LIU Xue SUN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第12期3318-3330,共13页
In order to obtain the optimized aircraft design concept which meets the increasingly complex operation environment at the conceptual design stage,System-of-systems(So S)engineering must be considered.This paper propo... In order to obtain the optimized aircraft design concept which meets the increasingly complex operation environment at the conceptual design stage,System-of-systems(So S)engineering must be considered.This paper proposes a novel optimization method for the design of aircraft Mission Success Space(MSS)based on Gaussian fitting and Genetic Algorithm(GA)in the So S area.First,the concepts in the design and evaluation of MSS are summarized to introduce the Contribution to System-of-Systems(CSS)by using a conventional effectiveness index,Mission Success Rate(MSR).Then,the mathematic modelling of Gaussian fitting technique is noted as the basis of the optimization work.After that,the proposed optimal MSS design is illustrated by the multiobjective optimization process where GA acts as the search tool to find the best solution(via Pareto front).In the case study,a simulation system of penetration mission was built.The simulation results are collected and then processed by two MSS design schemes(contour and neural network)giving the initial variable space to GA optimization.Based on that,the proposed optimization method is implemented under both schemes whose optimal solutions are compared to obtain the final best design in the case study. 展开更多
关键词 EVALUATION Gaussian fitting Genetic algorithm Mission success space Neural network System-of-systems
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Stable Perturbed Algorithms for a New Class of Generalized Nonlinear Implicit Quasi Variational Inclusions in Banach Spaces 被引量:2
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作者 Salahuddin Salahuddin Mohammad Kalimuddin Ahmad 《Advances in Pure Mathematics》 2012年第3期139-148,共10页
In this work, a new class of variational inclusion involving T-accretive operators in Banach spaces is introduced and studied. New iterative algorithms for stability for their class of variational inclusions and its c... In this work, a new class of variational inclusion involving T-accretive operators in Banach spaces is introduced and studied. New iterative algorithms for stability for their class of variational inclusions and its convergence results are established. 展开更多
关键词 T-Accretive Operators VARIATIONAL INCLUSIONS Iterative algorithms Stability Conditions Convergence Strong Accretivity BANACH spaces
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Multi-objective Collaborative Optimization for Scheduling Aircraft Landing on Closely Spaced Parallel Runways Based on Genetic Algorithms 被引量:1
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作者 Zhang Shuqin Jiang Yu Xia Hongshan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第4期502-509,共8页
A scheduling model of closely spaced parallel runways for arrival aircraft was proposed,with multi-objections of the minimum flight delay cost,the maximum airport capacity,the minimum workload of air traffic controlle... A scheduling model of closely spaced parallel runways for arrival aircraft was proposed,with multi-objections of the minimum flight delay cost,the maximum airport capacity,the minimum workload of air traffic controller and the maximum fairness of airlines′scheduling.The time interval between two runways and changes of aircraft landing order were taken as the constraints.Genetic algorithm was used to solve the model,and the model constrained unit delay cost of the aircraft with multiple flight tasks to reduce its delay influence range.Each objective function value or the fitness of particle unsatisfied the constrain condition would be punished.Finally,one domestic airport hub was introduced to verify the algorithm and the model.The results showed that the genetic algorithm presented strong convergence and timeliness for solving constraint multi-objective aircraft landing problem on closely spaced parallel runways,and the optimization results were better than that of actual scheduling. 展开更多
关键词 air transportation runway scheduling closely spaced parallel runways genetic algorithm multi-objections
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SINGLE PROJECTION ALGORITHM FOR VARIATIONAL INEQUALITIES IN BANACH SPACES WITH APPLICATION TO CONTACT PROBLEM 被引量:3
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作者 Yekini SHEHU 《Acta Mathematica Scientia》 SCIE CSCD 2020年第4期1045-1063,共19页
We study the single projection algorithm of Tseng for solving a variational inequality problem in a 2-uniformly convex Banach space.The underline cost function of the variational inequality is assumed to be monotone a... We study the single projection algorithm of Tseng for solving a variational inequality problem in a 2-uniformly convex Banach space.The underline cost function of the variational inequality is assumed to be monotone and Lipschitz continuous.A weak convergence result is obtained under reasonable assumptions on the variable step-sizes.We also give the strong convergence result for when the underline cost function is strongly monotone and Lipchitz continuous.For this strong convergence case,the proposed method does not require prior knowledge of the modulus of strong monotonicity and the Lipschitz constant of the cost function as input parameters,rather,the variable step-sizes are diminishing and non-summable.The asymptotic estimate of the convergence rate for the strong convergence case is also given.For completeness,we give another strong convergence result using the idea of Halpern iteration when the cost function is monotone and Lipschitz continuous and the variable step-sizes are bounded by the inverse of the Lipschitz constant of the cost function.Finally,we give an example of a contact problem where our proposed method can be applied. 展开更多
关键词 variational inequality 2-uniformly convex Banach space Tseng’s algorithm strong convergence rate of convergence
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Using Genetic Algorithms to Improve the Search of the Weight Space in Cascade-Correlation Neural Network 被引量:1
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作者 E.A.Mayer, K. J. Cios, L. Berke & A. Vary(University of Toledo, Toledo, OH 43606, U. S. A.)(NASA Lewis Research Center, Cleveland, OH) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第2期9-21,共13页
In this paper, we use the global search characteristics of genetic algorithms to help search the weight space of the neurons in the cascade-correlation architecture. The cascade-correlation learning architecture is a ... In this paper, we use the global search characteristics of genetic algorithms to help search the weight space of the neurons in the cascade-correlation architecture. The cascade-correlation learning architecture is a technique of training and building neural networks that starts with a simple network of neurons and adds additional neurons as they are needed to suit a particular problem. In our approach, instead ofmodifying the genetic algorithm to account for convergence problems, we search the weight-space using the genetic algorithm and then apply the gradient technique of Quickprop to optimize the weights. This hybrid algorithm which is a combination of genetic algorithms and cascade-correlation is applied to the two spirals problem. We also use our algorithm in the prediction of the cyclic oxidation resistance of Ni- and Co-base superalloys. 展开更多
关键词 Genetic algorithm Cascade correlation Weight space search Neural network.
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Space gripper configuration and its dimension synthesis based on genetic algorithm 被引量:1
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作者 朱映远 Shi Shicai +1 位作者 Xie Zongwu Liu Hong 《High Technology Letters》 EI CAS 2008年第3期300-303,共4页
The special fingers of the gripper on the space robot have been developed based on genetic algorithmfor the space application.Therefore,the symmetrical wedgelike finger composed of the 4-1ink mechanismand the relevant... The special fingers of the gripper on the space robot have been developed based on genetic algorithmfor the space application.Therefore,the symmetrical wedgelike finger composed of the 4-1ink mechanismand the relevant track were designed.To decrease the weight and optimize the kinematics and grip force,the compositive fitness function for dynamics and kinematics was created.The calculation efficiency couldbe improved by novel methods which overcame the problem of too many constraints in the solution space,such as introducing the specialist's experience and punishment function and simplifying the variables.The solutions show that the optimized finger could perform well and the methods were effectual. 展开更多
关键词 space finger genetic algorithm dimension synthesis
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Directional Routing Algorithm for Deep Space Optical Network
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作者 Lei Guo Xiaorui Wang +3 位作者 Yejun Liu Pengchao Han Yamin Xie Yuchen Tan 《China Communications》 SCIE CSCD 2017年第1期158-168,共11页
With the development of science, economy and society, the needs for research and exploration of deep space have entered a rapid and stable development stage. Deep Space Optical Network(DSON) is expected to become an i... With the development of science, economy and society, the needs for research and exploration of deep space have entered a rapid and stable development stage. Deep Space Optical Network(DSON) is expected to become an important foundation and inevitable development trend of future deepspace communication. In this paper, we design a deep space node model which is capable of combining the space division multiplexing with frequency division multiplexing. Furthermore, we propose the directional flooding routing algorithm(DFRA) for DSON based on our node model. This scheme selectively forwards the data packets in the routing, so that the energy consumption can be reduced effectively because only a portion of nodes will participate the flooding routing. Simulation results show that, compared with traditional flooding routing algorithm(TFRA), the DFRA can avoid the non-directional and blind transmission. Therefore, the energy consumption in message routing will be reduced and the lifespan of DSON can also be prolonged effectively. Although the complexity of routing implementation is slightly increased compared with TFRA, the energy of nodes can be saved and the transmission rate is obviously improved in DFRA. Thus the overall performance of DSON can be significantly improved. 展开更多
关键词 deep space optical network routing algorithm directional flooding routing algorithm traditional flooding routing algorithm
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Multi-objective Evolutionary Algorithm Based on Target Space Partitioning Method
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作者 尚兆霞 刘弘 李焱 《Journal of Donghua University(English Edition)》 EI CAS 2011年第2期177-181,共5页
Considering the defects of conventional optimization methods, a novel optimization algorithm is introduced in this paper. Target space partitioning method is used in this algorithm to solve multi-objective optimizatio... Considering the defects of conventional optimization methods, a novel optimization algorithm is introduced in this paper. Target space partitioning method is used in this algorithm to solve multi-objective optimization problem, thus achieve the coherent solution which can meet the requirements of all target functions, and improve the population's overall evolution level. The algorithm which guarantees diversity preservation and fast convergence to the Pareto set is applied to structural optimization problems. The empirical analysis supports the algorithm and gives an example with program. 展开更多
关键词 OPTIMIZATION algorithm MULTI-OBJECTIVE TARGET space partitioning METHOD
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STATE SPACE TREE METHOD AND EXACT DECOMPOSITION ALGORITHM FOR FINDING NETWORK OVERALL RELIABILITY
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作者 黄汝激 《Journal of Electronics(China)》 1990年第4期296-305,共10页
First,the state space tree method for finding communication network overall re-liability is presented.It directly generates one disjoint tree multilevel polynomial of a networkgraph.Its advantages are smaller computat... First,the state space tree method for finding communication network overall re-liability is presented.It directly generates one disjoint tree multilevel polynomial of a networkgraph.Its advantages are smaller computational effort(its computing time complexity is O(en_l),where e is the number of edges and n_l is the number of leaves)and shorter resulting expression.Second,based on it an exact decomposition algorithm for finding communication network overallreliability is presented by applying the hypergraph theory.If we use it to carry out the m-timedecomposition of a network graph,the communication network scale which can be analyzed by acomputer can be extended to m-fold. 展开更多
关键词 Communication NETWORK Overall RELIABILITY GRAPH HYPERGRAPH State space TREE EXACT decomposition algorithm
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ALGORITHM OF SOLUTIONS FOR MIXEDNONLINEAR VARIATIONAL-LIKE INEQUALITIES IN REFLEXIVE BANACH SPACE
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作者 丁协平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第6期521-529,共9页
In this paper, the author studies a class of mixed nonlinear variational-like inequalities in reflexive Banach space. By applying a minimax inequality obtained by the author, some existence uniqueness theorems of solu... In this paper, the author studies a class of mixed nonlinear variational-like inequalities in reflexive Banach space. By applying a minimax inequality obtained by the author, some existence uniqueness theorems of solutions for the mixed nonlinear variational-like inequalities are proved. Next, by applying the auxiliary problem technique, rite author suggests an innovative iterative algorithm to compute the approximate solutions of the mixed nonlinear variational-like inequalities. Finally, the convergence criteria is also discussed. 展开更多
关键词 mixed nonlinear variational-like inequality minimax inequality auxiliary variational inequality general algorithm reflexive Banach space
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An Orthogonal Wavelet Transform Fractionally Spaced Blind Equalization Algorithm Based on the Optimization of Genetic Algorithm
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作者 廖娟 郭业才 季童莹 《Defence Technology(防务技术)》 SCIE EI CAS 2011年第2期65-71,共7页
An orthogonal wavelet transform fractionally spaced blind equalization algorithm based on the optimization of genetic algorithm(WTFSE-GA) is proposed in viewof the lowconvergence rate,large steady-state mean square er... An orthogonal wavelet transform fractionally spaced blind equalization algorithm based on the optimization of genetic algorithm(WTFSE-GA) is proposed in viewof the lowconvergence rate,large steady-state mean square error and local convergence of traditional constant modulus blind equalization algorithm(CMA).The proposed algorithm can reduce the signal autocorrelation through the orthogonal wavelet transform of input signal of fractionally spaced blind equalizer,and decrease the possibility of CMA local convergence by using the global random search characteristics of genetic algorithm to optimize the equalizer weight vector.The proposed algorithm has the faster convergence rate and smaller mean square error compared with FSE and WT-FSE.The efficiency of the proposed algorithm is proved by computer simulation of underwater acoustic channels. 展开更多
关键词 information processing technique genetic algorithm orthogonal wavelet transform fractionally spaced equalizer blind equalization underwater acoustic channel
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Existence and algorithm of solutions for a system of generalized mixed implicit equilibrium problems in Banach spaces
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作者 丁协平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第9期1049-1062,共14页
A new system of generalized mixed implicit equilibrium problems is introduced and studied in Banach spaces. First, the notion of the Yosida proximal mapping for generalized mixed implicit equilibrium problems is intro... A new system of generalized mixed implicit equilibrium problems is introduced and studied in Banach spaces. First, the notion of the Yosida proximal mapping for generalized mixed implicit equilibrium problems is introduced. By using the notion, a system of generalized equation problems is considered, and its equivalence with the system of generalized mixed implicit equilibrium problems is also proved. Next, by applying the system of generalized equation problems, we suggest and analyze an iterative algorithm to compute the approximate solutions of the system of generalized mixed implicit equilibrium problems. The strong convergence of the iterative sequences generated by the algorithm is proved under quite mild conditions. The results are new and unify and generalize some recent results in this field. 展开更多
关键词 generalized mixed implicit equilibrium problem Yosida proximal mapping generalized equation problem iterative algorithm Banach space
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Space-borne antenna adaptive anti-jamming method based on gradient-genetic algorithm 被引量:2
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作者 Tao Haihong Liao Guisheng Yu Jiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期469-475,共7页
A novel space-borne antenna adaptive anti-jamming method based on the genetic algorithm (GA), which is combined with gradient-like reproduction operators is presented, to search for the best weight for pattern synth... A novel space-borne antenna adaptive anti-jamming method based on the genetic algorithm (GA), which is combined with gradient-like reproduction operators is presented, to search for the best weight for pattern synthesis in radio frequency (RF). Combined, the GA's the capability of the whole searching is, but not limited by selection of the initial parameter, with the gradient algorithm's advantage of fast searching. The proposed method requires a smaller sized initial population and lower computational complexity. Therefore, it is flexible to implement this method in the real-time systems. By using the proposed algorithm, the designer can efficiently control both main-lobe shaping and side-lobe level. Simulation results based on the spot survey data show that the algorithm proposed is efficient and feasible. 展开更多
关键词 space-borne antenna genetic algorithm (GA) gradient-like ANTI-JAMMING pattern synthesis.
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