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基于TLBO算法的不确定性条件下复杂产品协同设计的可靠性拓扑优化

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Engineering 2023年第3期22卷 71-81页

作者： Zhaoxi Hong Xiangyu Jiang 冯毅雄 Qinyu Tian 谭建荣 State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China Key Laboratory of Advanced Manufacturing Technology of Zhejiang Province Zhejiang UniversityHangzhou 310027China

复杂产品的拓扑优化设计可以显著节省材料和节能,有效地降低惯性力和机械振动。本研究以一种大吨位液压机作为典型的复杂产品,用于阐述该优化方法。本文提出了一种基于可靠性与优化解耦模型和基于教学学习的优化(TLBO)算法的可靠性拓扑... 详细信息

复杂产品的拓扑优化设计可以显著节省材料和节能,有效地降低惯性力和机械振动。本研究以一种大吨位液压机作为典型的复杂产品,用于阐述该优化方法。本文提出了一种基于可靠性与优化解耦模型和基于教学学习的优化(TLBO)算法的可靠性拓扑优化方法。将由板结构形成的支撑物作为拓扑优化对象,重量轻、稳定性好。将不确定性下的可靠性优化和结构拓扑优化协同处理。首先,利用有限差分法将优化问题中的不确定性参数修正为确定性参数。然后,将不确定性可靠性分析和拓扑优化的复杂嵌套解耦。最后,利用TLBO算法求解解耦模型,该算法参数少,求解速度快。TLBO算法采用了自适应教学因子,在初始阶段实现了更快的收敛速度,并在后期进行了更精细的搜索。本文给出了一个液压机基板结构的数值实例,说明了该方法的有效性。

关键词： Plates structure Reliability Collaborative topology optimization Teaching-learning-based optimization algorithm Uncertainty Collaborative design for product life cycle

algorithm design and the development of a discrete element method for simulating particulate flow and heat transfer

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Clean Energy 2021年第2期5卷 141-166页

作者： Bing Liu National Institute of Clean-and-Low-Carbon Energy CHN Energy InvestmentBeijing 102211P.R.China

An algorithm using the discrete element method(DEM)for simulating the particulate behaviour of flow and heat transfer is developed and described,the reasonable hypothesis and the ingenious design of which have been presented in detail.The organizational structure of the developed algorithm contains an efficient method for determining particle collisions,the status analysis for each particle and the particulate-kinematics analysis during the time step.The reasonability and correctness of the developed DEM algorithm are validated by laboratory experiments:the discharge process of glass beads from a silo;and heating of metal alloy particles in a calciner.Afterwards,a group of validated mechanics parameter values for coal and sand have been tested and verified in the article,preparing for the simulation of the pyrolysis process in a downer or screw reactor in subsequent research projects.

关键词： DEM algorithm particulate flow solid mechanics heat-transfer model

Speckle spatial correlations aiding optical transmission matrix retrieval:the smoothed Gerchberg–Saxton single-iteration algorithm

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Photonics Research 2022年第10期10卷 2349-2358页

作者： DANIELE ANCORA LORENZO DOMINICI ANTONIO GIANFRATE PAOLO CAZZATO MILENA DE GIORGI DARIO BALLARINI DANIELE SANVITTO LUCA LEUZZI Department of Physics Universitàdi Roma la SapienzaPiazzale Aldo Moro 5I-00185 RomeItaly Institute of Nanotechnology Consiglio Nazionale delle Ricerche(CNR-NANOTEC)Via MonteroniI-73100 LecceItaly Institute of Nanotechnology Soft and Living Matter LaboratoryConsiglio Nazionale delle Ricerche(CNR-NANOTEC)Piazzale Aldo Moro 5I-00185 RomeItaly

The estimation of the transmission matrix of a disordered medium is a challenging problem in disordered photonics.Usually,its reconstruction relies on a complex inversion that aims at connecting a fully controlled input to the deterministic interference of the light field scrambled by the device.At the moment,iterative phase retrieval protocols provide the fastest reconstructing frameworks,converging in a few tens of iterations.Exploiting the knowledge of speckle correlations,we construct a new phase retrieval algorithm that reduces the computational cost to a single iteration.Besides being faster,our method is practical because it accepts fewer measurements than state-of-the-art protocols.Thanks to reducing computation time by one order of magnitude,our result can be a step forward toward real-time optical imaging that exploits disordered devices.

关键词： optical matrix algorithm

A nonlinear wave coupling algorithm and its programing and application in plasma turbulences

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Chinese Physics B 2022年第6期31卷 541-548页

作者：沈勇沈煜航董家齐赵开君石中兵李继全 Southwestern Institute of Physics Chengdu 610041China School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Institute for Fusion Theory and Simulation Zhejiang UniversityHangzhou 310013China College of Nuclear Science and Engineer East China University of TechnologyNanchang 330013China

The fully developed turbulence can be regarded as a nonlinear system,with wave coupling inside,which causes the nonlinear energy to transfer,and drives the turbulence to develop further or be suppressed.Spectral analysis is one of the most effective methods to study turbulence system.In order to apply it to the study of the nonlinear wave coupling process of edge plasma turbulence,an efficient algorithm based on spectral analysis technology is proposed to solve the nonlinear wave coupling equation.The algorithm is based on a mandatory temporal static condition with the nonideal spectra separated from the ideal spectra.The realization idea and programing flow are given.According to the characteristics of plasma turbulence,the simulation data are constructed and used to verify the algorithm and its implementation program.The simulation results and experimental results show the accuracy of the algorithm and the corresponding program,which can play a great role in the studying the energy transfer in edge plasma turbulences.As an application,the energy cascade analysis of typical edge plasma turbulence is carried out by using the results of a case calculation.Consequently,a physical picture of the energy transfer in a kind of fully developed turbulence is constructed,which confirms that the energy transfer in this turbulent system develops from lower-frequency region to higher-frequency region and from linear growing wave to damping wave.

关键词： bispectral analysis wave coupling algorithm plasma turbulence energy cascade

Pressure sensing recognition of FBG array based on random forest algorithm

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Optoelectronics Letters 2023年第5期19卷 262-268页

作者： WANG Yan ZHU Wei GE Ziyang WANG Junliang XU Haoyu JIANG Chao School of Electrical and Information Engineering Anhui University of TechnologyMaanshan 243000China

In order to improve the precision of static load pressure recognition and identify the position of the applied force accurately,a fiber Bragg grating(FBG)flexible sensor array is proposed in this work.Numerical analysis for the package thickness(4 mm)and package position(2 mm from the bottom)of the FBG flexible sensor is performed using COMSOL,and optimal package thickness(4 mm)and package position(2 mm from the bottom)are selected in the analysis.By using 12-FBGs layout method and random forest algorithm,the position and load prediction model is established.The results show that the average error of the distance between the prediction points of coordinates X-Y and static load F and the real sample points is 0.092.Finally,to verify the proposed models,the pressure sensing experiments of the flexible FBG array are carried out on this basis.The weights of 100 g to 1000 g are applied to different regions of the flexible sensor array one by one in accordance with a certain trajectory.The variation of each FBG wavelength was taken as the input of the stochastic forest prediction model,and the coordinate position and the static load size F were taken as the output to establish the prediction model.The minimum distance error between the actual point and the predicted point was calculated by experiment as 0.03491.The maximum is 0.2481,and the mean error is 0.1515.It is concluded that the random forest prediction model has a good prediction effect on the pressure sensing of the flexible FBG sensing array.

关键词： prediction random algorithm

Improved sparrow search algorithm for RFID network planning

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中国邮电高校学报：英文版 2023年第1期30卷 93-102页

作者： Zhang Jiangbo Zheng Jiali Quan Yixuan Lin Zihan Xie Xiaode School of Computer Electrics and InformationGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Multimedia Communications and Network Technology Guangxi UniversityNanning 530004China

To solve the problem that the performance of the coverage,interference rate,load balance andweak power in the radio frequency identification(RFID)network planning.This paper proposes an elite opposition-based learning and Lévy flight sparrow search algorithm(SSA),which is named elite opposition-based learning and Levy flight SSA(ELSSA).First,the algorithm initializes the population by an elite opposed-based learning strategy to enhance the diversity of the population.Second,Lévy flight is introduced into the scrounger’s position update formula to solve the situation that the algorithm falls into the local optimal solution.It has a probability that the current position is changed by Lévy flight.This method can jump out of the local optimal solution.In the end,the proposed method is compared with particle swarm optimization(PSO)algorithm,grey wolf optimzer(GWO)algorithm and SSA in the multiple simulation tests.The simulated results showed that,under the same number of readers,the average fitness of the ELSSA is improved respectively by 3.36%,5.67%and 18.45%.By setting the different number of readers,ELSSA uses fewer readers than other algorithms.The conclusion shows that the proposed method can ensure a satisfying coverage by using fewer readers and achieving higher comprehensive performance.

关键词： radio frequency identification network planning sparrow search algorithm elite opposition-based learning Levy flight

Bit level image encryption algorithm based on hyperchaotic system

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光电子快报：英文版 2023年第3期19卷 186-192页

作者： MAN Zhenlong ZHANG Yue ZHOU Ying LU Xiaoli WANG Zhaoquan School of Electronic and Information Engineering Liaoning Technical UniversityHuludao 125100China Advanced Interactive Technology and Application Laboratory Computer Network Information CenterChinese Academy of SciencesBeijing 100190China

Because chaotic systems are unpredictable,ergodic and sensitive to initial values and parameters,they are often used in the field of encryption.To avoid the bad randomness of the random key generated by the low dimensional chaotic map system,a 5-dimensional multi-wing hyperchaotic system is adopted in this paper.The key stream generated by the chaotic system is related to the plaintext image.So it can effectively resist the attacks of selecting plaintext.The plaintext graph is decomposed into binary form by bit plane decomposition technique,and then these bit planes are divided into high and low groups.The designed control matrix is used to identify the specific scrambling mode,and each bit is permuted within and between groups.Finally,bit diffusion is used to change the pixel value of each pixel.Theoretical analysis and numerical simulation show that the algorithm has good encryption performance for image encryption.

关键词： chaotic system algorithm

Multi-level modulation scheme based on PAK algorithm for optical camera communications

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Optoelectronics Letters 2022年第3期18卷 152-157页

作者： WU Jing CHI Xuefen JI Fenglei JIANG Keyu CHEN Shaoqi LI Shuai Department of Communications Engineering Jilin UniversityChangchun 130012China

In an optical camera communication(OCC) system, multi-level modulation is essential for data rate enhancement with the finite frame rate of the receiving camera constraint, where the K-means algorithm is widely used as a thresholding scheme. The result of K-means clustering is sensitive to initial cluster centers. In this paper, we propose a multi-level modulation scheme utilizing the pilot-aided K-means(PAK) algorithm. PAK algorithm innovates in both obtaining the state of the stripes propagated through the optical channel under different environments and overcoming the susceptibility of K-means. Our scheme could prompt data rate and improve the performance of OCC. Finally, non-orthogonal multiple access(NOMA) pattern is designed based on the proposed scheme to achieve multiplex communications.

关键词： prompt scheme algorithm

A Novel Metaheuristic algorithm: The Team Competition and Cooperation Optimization algorithm

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Computers, Materials & Continua 2022年第11期73卷 2879-2896页

作者： Tao Wu Xinyu Wu Jingjue Chen Xi Chen Amir Homayoon Ashrafzadeh School of Computer Science Chengdu University of Information TechnologyChengdu610225China School of Computer Science and Engineering Southwest Minzu UniversityChengdu610041China CSIT Department School of ScienceRMIT UniversityMelbourne3058Australia

Metaheuristic algorithm is a generalization of heuristic algorithm that can be applied to almost all optimization problems.For optimization problems,metaheuristic algorithm is one of the methods to find its optimal solution or approximate solution under limited conditions.Most of the existing metaheuristic algorithms are designed for serial systems.Meanwhile,existing algorithms still have a lot of room for improvement in convergence speed,robustness,and performance.To address these issues,this paper proposes an easily parallelizable metaheuristic optimization algorithm called team competition and cooperation optimization(TCCO)inspired by the process of human team cooperation and competition.The proposed algorithm attempts to mathematically model human team cooperation and competition to promote the optimization process and find an approximate solution as close as possible to the optimal solution under limited conditions.In order to evaluate the performance of the proposed algorithm,this paper compares the solution accuracy and convergence speed of the TCCO algorithm with the Grasshopper Optimization algorithm(GOA),Seagull Optimization algorithm(SOA),Whale Optimization algorithm(WOA)and Sparrow Search algorithm(SSA).Experiment results of 30 test functions commonly used in the optimization field indicate that,compared with these current advanced metaheuristic algorithms,TCCO has strong competitiveness in both solution accuracy and convergence speed.

关键词： Optimization metaheuristic algorithm