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A Boundary Element Reconstruction (BER) Model for Moving Morphable Component Topology Optimization
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作者 Zhao Li Hongyu Xu +2 位作者 Shuai Zhang Jintao Cui Xiaofeng Liu 《Computers, Materials & Continua》 2026年第1期2213-2230,共18页
The moving morphable component(MMC)topology optimization method,as a typical explicit topology optimization method,has been widely concerned.In the MMC topology optimization framework,the surrogate material model is m... The moving morphable component(MMC)topology optimization method,as a typical explicit topology optimization method,has been widely concerned.In the MMC topology optimization framework,the surrogate material model is mainly used for finite element analysis at present,and the effectiveness of the surrogate material model has been fully confirmed.However,there are some accuracy problems when dealing with boundary elements using the surrogate material model,which will affect the topology optimization results.In this study,a boundary element reconstruction(BER)model is proposed based on the surrogate material model under the MMC topology optimization framework to improve the accuracy of topology optimization.The proposed BER model can reconstruct the boundary elements by refining the local meshes and obtaining new nodes in boundary elements.Then the density of boundary elements is recalculated using the new node information,which is more accurate than the original model.Based on the new density of boundary elements,the material properties and volume information of the boundary elements are updated.Compared with other finite element analysis methods,the BER model is simple and feasible and can improve computational accuracy.Finally,the effectiveness and superiority of the proposed method are verified by comparing it with the optimization results of the original surrogate material model through several numerical examples. 展开更多
关键词 Topology optimization MMC method boundary element reconstruction surrogate material model local mesh
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Efficient Arabic Essay Scoring with Hybrid Models: Feature Selection, Data Optimization, and Performance Trade-Offs
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作者 Mohamed Ezz Meshrif Alruily +4 位作者 Ayman Mohamed Mostafa Alaa SAlaerjan Bader Aldughayfiq Hisham Allahem Abdulaziz Shehab 《Computers, Materials & Continua》 2026年第1期2274-2301,共28页
Automated essay scoring(AES)systems have gained significant importance in educational settings,offering a scalable,efficient,and objective method for evaluating student essays.However,developing AES systems for Arabic... Automated essay scoring(AES)systems have gained significant importance in educational settings,offering a scalable,efficient,and objective method for evaluating student essays.However,developing AES systems for Arabic poses distinct challenges due to the language’s complex morphology,diglossia,and the scarcity of annotated datasets.This paper presents a hybrid approach to Arabic AES by combining text-based,vector-based,and embeddingbased similarity measures to improve essay scoring accuracy while minimizing the training data required.Using a large Arabic essay dataset categorized into thematic groups,the study conducted four experiments to evaluate the impact of feature selection,data size,and model performance.Experiment 1 established a baseline using a non-machine learning approach,selecting top-N correlated features to predict essay scores.The subsequent experiments employed 5-fold cross-validation.Experiment 2 showed that combining embedding-based,text-based,and vector-based features in a Random Forest(RF)model achieved an R2 of 88.92%and an accuracy of 83.3%within a 0.5-point tolerance.Experiment 3 further refined the feature selection process,demonstrating that 19 correlated features yielded optimal results,improving R2 to 88.95%.In Experiment 4,an optimal data efficiency training approach was introduced,where training data portions increased from 5%to 50%.The study found that using just 10%of the data achieved near-peak performance,with an R2 of 85.49%,emphasizing an effective trade-off between performance and computational costs.These findings highlight the potential of the hybrid approach for developing scalable Arabic AES systems,especially in low-resource environments,addressing linguistic challenges while ensuring efficient data usage. 展开更多
关键词 Automated essay scoring text-based features vector-based features embedding-based features feature selection optimal data efficiency
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Energy Optimization for Autonomous Mobile Robot Path Planning Based on Deep Reinforcement Learning
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作者 Longfei Gao Weidong Wang Dieyun Ke 《Computers, Materials & Continua》 2026年第1期984-998,共15页
At present,energy consumption is one of the main bottlenecks in autonomous mobile robot development.To address the challenge of high energy consumption in path planning for autonomous mobile robots navigating unknown ... At present,energy consumption is one of the main bottlenecks in autonomous mobile robot development.To address the challenge of high energy consumption in path planning for autonomous mobile robots navigating unknown and complex environments,this paper proposes an Attention-Enhanced Dueling Deep Q-Network(ADDueling DQN),which integrates a multi-head attention mechanism and a prioritized experience replay strategy into a Dueling-DQN reinforcement learning framework.A multi-objective reward function,centered on energy efficiency,is designed to comprehensively consider path length,terrain slope,motion smoothness,and obstacle avoidance,enabling optimal low-energy trajectory generation in 3D space from the source.The incorporation of a multihead attention mechanism allows the model to dynamically focus on energy-critical state features—such as slope gradients and obstacle density—thereby significantly improving its ability to recognize and avoid energy-intensive paths.Additionally,the prioritized experience replay mechanism accelerates learning from key decision-making experiences,suppressing inefficient exploration and guiding the policy toward low-energy solutions more rapidly.The effectiveness of the proposed path planning algorithm is validated through simulation experiments conducted in multiple off-road scenarios.Results demonstrate that AD-Dueling DQN consistently achieves the lowest average energy consumption across all tested environments.Moreover,the proposed method exhibits faster convergence and greater training stability compared to baseline algorithms,highlighting its global optimization capability under energy-aware objectives in complex terrains.This study offers an efficient and scalable intelligent control strategy for the development of energy-conscious autonomous navigation systems. 展开更多
关键词 Autonomous mobile robot deep reinforcement learning energy optimization multi-attention mechanism prioritized experience replay dueling deep Q-Network
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Mo、W对多晶铸造镍基高温合金组织及应用性能影响的研究进展
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作者 谢树磊 欧美琼 +2 位作者 侯坤磊 王旻 马颖澈 《材料导报》 北大核心 2026年第1期159-169,共11页
多晶铸造镍基高温合金主要应用于航空发动机机匣等需要整体铸造的较大尺寸、结构复杂的热端部件。随着发动机性能和部件服役温度的不断提高,多晶铸造镍基高温合金的合金化程度也不断提高。Mo、W元素在高温合金中具有重要的强化作用,其... 多晶铸造镍基高温合金主要应用于航空发动机机匣等需要整体铸造的较大尺寸、结构复杂的热端部件。随着发动机性能和部件服役温度的不断提高,多晶铸造镍基高温合金的合金化程度也不断提高。Mo、W元素在高温合金中具有重要的强化作用,其主要通过固溶强化效应以及参与第二相析出的方式提高合金的力学性能,目前Mo、W元素的强化效果及相关机理得到了较为充分的研究。本文主要总结了Mo、W元素在枝晶、碳化物、TCP、γ/γ′组织的分布以及对它们形貌与稳定性的影响,同时对当前两种元素对合金的强度、焊接及抗氧化性等应用性能的影响及相关机理的研究进行了总结。 展开更多
关键词 多晶 铸造 高温合金 mo W 微观组织 力学性能
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A Modified PRP-HS Hybrid Conjugate Gradient Algorithm for Solving Unconstrained Optimization Problems 被引量:1
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作者 LI Xiangli WANG Zhiling LI Binglan 《应用数学》 北大核心 2025年第2期553-564,共12页
In this paper,we propose a three-term conjugate gradient method for solving unconstrained optimization problems based on the Hestenes-Stiefel(HS)conjugate gradient method and Polak-Ribiere-Polyak(PRP)conjugate gradien... In this paper,we propose a three-term conjugate gradient method for solving unconstrained optimization problems based on the Hestenes-Stiefel(HS)conjugate gradient method and Polak-Ribiere-Polyak(PRP)conjugate gradient method.Under the condition of standard Wolfe line search,the proposed search direction is the descent direction.For general nonlinear functions,the method is globally convergent.Finally,numerical results show that the proposed method is efficient. 展开更多
关键词 Conjugate gradient method Unconstrained optimization Sufficient descent condition Global convergence
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Mo含量对激光增材制造TC4钛合金组织与性能影响
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作者 陈祖斌 王旭红 +2 位作者 汤华国 潘昆明 朱礼龙 《稀有金属材料与工程》 北大核心 2026年第1期124-135,共12页
TC4钛合金因其出色的力学性能和优异的生物相容性,在航空航天及医疗器械领域具有广泛的应用。激光增材制造(LAM)是钛合金成形制造的重要手段,增材制造TC4钛合金内部存在大量的柱状晶和针状的马氏体,会导致材料性能存在各向异性、塑性降... TC4钛合金因其出色的力学性能和优异的生物相容性,在航空航天及医疗器械领域具有广泛的应用。激光增材制造(LAM)是钛合金成形制造的重要手段,增材制造TC4钛合金内部存在大量的柱状晶和针状的马氏体,会导致材料性能存在各向异性、塑性降低。本研究采用添加钼(Mo)对增材制造TC4钛合金进行组织性能调控,旨在探究Mo含量对激光增材制造TC4钛合金的组织结构和性能的影响。结果表明:适量的Mo含量能有效细化晶粒,随Mo元素的添加,合金基体中逐渐析出TiAl_(3)相,其含量随Mo含量的增加而增多,当Mo含量达到8wt%,合金中分布着细小弥散的片层状组织,β相的含量急剧增加,晶粒细化程度和位错密度均达到最大值。随Mo含量从0增加到10wt%,合金的抗拉强度、硬度呈先增大后减小趋势,伸长率先减小后增大,杨氏模量逐渐降低,而耐腐蚀性能呈先上升后下降趋势。当Mo含量为8wt%,合金获得最佳的强度与塑性匹配,抗拉强度、伸长率和杨氏模量值分别为1065.6 MPa、11.5%和55.4 GPa,合金耐腐蚀性能有所提升。综合考虑,TC4-8Mo试样有着优良的力学性能和良好的耐腐蚀性能,具有做人体医学植入物材料的潜力。 展开更多
关键词 钛合金 激光增材制造 微观组织 mo含量
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A survey on multi-objective,model-based,oil and gas field development optimization:Current status and future directions 被引量:1
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作者 Auref Rostamian Matheus Bernardelli de Moraes +1 位作者 Denis Jose Schiozer Guilherme Palermo Coelho 《Petroleum Science》 2025年第1期508-526,共19页
In the area of reservoir engineering,the optimization of oil and gas production is a complex task involving a myriad of interconnected decision variables shaping the production system's infrastructure.Traditionall... In the area of reservoir engineering,the optimization of oil and gas production is a complex task involving a myriad of interconnected decision variables shaping the production system's infrastructure.Traditionally,this optimization process was centered on a single objective,such as net present value,return on investment,cumulative oil production,or cumulative water production.However,the inherent complexity of reservoir exploration necessitates a departure from this single-objective approach.Mul-tiple conflicting production and economic indicators must now be considered to enable more precise and robust decision-making.In response to this challenge,researchers have embarked on a journey to explore field development optimization of multiple conflicting criteria,employing the formidable tools of multi-objective optimization algorithms.These algorithms delve into the intricate terrain of production strategy design,seeking to strike a delicate balance between the often-contrasting objectives.Over the years,a plethora of these algorithms have emerged,ranging from a priori methods to a posteriori approach,each offering unique insights and capabilities.This survey endeavors to encapsulate,catego-rize,and scrutinize these invaluable contributions to field development optimization,which grapple with the complexities of multiple conflicting objective functions.Beyond the overview of existing methodologies,we delve into the persisting challenges faced by researchers and practitioners alike.Notably,the application of multi-objective optimization techniques to production optimization is hin-dered by the resource-intensive nature of reservoir simulation,especially when confronted with inherent uncertainties.As a result of this survey,emerging opportunities have been identified that will serve as catalysts for pivotal research endeavors in the future.As intelligent and more efficient algo-rithms continue to evolve,the potential for addressing hitherto insurmountable field development optimization obstacles becomes increasingly viable.This discussion on future prospects aims to inspire critical research,guiding the way toward innovative solutions in the ever-evolving landscape of oil and gas production optimization. 展开更多
关键词 Derivative-free algorithms Ensemble-based optimization Gradient-based methods Life-cycle optimization Reservoir field development and management
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Reactive Power Optimization Model of Active Distribution Network with New Energy and Electric Vehicles 被引量:1
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作者 Chenxu Wang Jing Bian Rui Yuan 《Energy Engineering》 2025年第3期985-1003,共19页
Considering the uncertainty of grid connection of electric vehicle charging stations and the uncertainty of new energy and residential electricity load,a spatio-temporal decoupling strategy of dynamic reactive power o... Considering the uncertainty of grid connection of electric vehicle charging stations and the uncertainty of new energy and residential electricity load,a spatio-temporal decoupling strategy of dynamic reactive power optimization based on clustering-local relaxation-correction is proposed.Firstly,the k-medoids clustering algorithm is used to divide the reduced power scene into periods.Then,the discrete variables and continuous variables are optimized in the same period of time.Finally,the number of input groups of parallel capacitor banks(CB)in multiple periods is fixed,and then the secondary static reactive power optimization correction is carried out by using the continuous reactive power output device based on the static reactive power compensation device(SVC),the new energy grid-connected inverter,and the electric vehicle charging station.According to the characteristics of the model,a hybrid optimization algorithm with a cross-feedback mechanism is used to solve different types of variables,and an improved artificial hummingbird algorithm based on tent chaotic mapping and adaptive mutation is proposed to improve the solution efficiency.The simulation results show that the proposed decoupling strategy can obtain satisfactory optimization resultswhile strictly guaranteeing the dynamic constraints of discrete variables,and the hybrid algorithm can effectively solve the mixed integer nonlinear optimization problem. 展开更多
关键词 Active distribution network new energy electric vehicles dynamic reactive power optimization kmedoids clustering hybrid optimization algorithm
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Enhanced Lead and Zinc Removal via Prosopis Cineraria Leaves Powder: A Study on Isotherms and RSM Optimization 被引量:1
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作者 Rakesh Namdeti Gaddala Babu Rao +7 位作者 Nageswara Rao Lakkimsetty Noor Mohammed Said Qahoor Naveen Prasad B.S Uma Reddy Meka Prema.P.M Doaa Salim Musallam Samhan Al-Kathiri Muayad Abdullah Ahmed Qatan Hafidh Ahmed Salim Ba Alawi 《Journal of Environmental & Earth Sciences》 2025年第1期292-305,共14页
This study investigates the potential of Prosopis cineraria Leaves Powder(PCLP)as a biosorbent for removing lead(Pb)and zinc(Zn)from aqueous solutions,optimizing the process using Response Surface Methodology(RSM).Pro... This study investigates the potential of Prosopis cineraria Leaves Powder(PCLP)as a biosorbent for removing lead(Pb)and zinc(Zn)from aqueous solutions,optimizing the process using Response Surface Methodology(RSM).Prosopis cineraria,commonly known as Khejri,is a drought-resistant tree with significant promise in environmental applications.The research employed a Central Composite Design(CCD)to examine the independent and combined effects of key process variables,including initial metal ion concentration,contact time,pH,and PCLP dosage.RSM was used to develop mathematical models that explain the relationship between these factors and the efficiency of metal removal,allowing the determination of optimal operating conditions.The experimental results indicated that the Langmuir isotherm model was the most appropriate for describing the biosorption of both metals,suggesting favorable adsorption characteristics.Additionally,the D-R isotherm confirmed that chemisorption was the primary mechanism involved in the biosorption process.For lead removal,the optimal conditions were found to be 312.23 K temperature,pH 4.72,58.5 mg L-1 initial concentration,and 0.27 g biosorbent dosage,achieving an 83.77%removal efficiency.For zinc,the optimal conditions were 312.4 K,pH 5.86,53.07 mg L-1 initial concentration,and the same biosorbent dosage,resulting in a 75.86%removal efficiency.These findings highlight PCLP’s potential as an effective,eco-friendly biosorbent for sustainable heavy metal removal in water treatment. 展开更多
关键词 Prosopis Cineraria LEAD ZINC Isotherms optimization
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DDoS Attack Autonomous Detection Model Based on Multi-Strategy Integrate Zebra Optimization Algorithm
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作者 Chunhui Li Xiaoying Wang +2 位作者 Qingjie Zhang Jiaye Liang Aijing Zhang 《Computers, Materials & Continua》 SCIE EI 2025年第1期645-674,共30页
Previous studies have shown that deep learning is very effective in detecting known attacks.However,when facing unknown attacks,models such as Deep Neural Networks(DNN)combined with Long Short-Term Memory(LSTM),Convol... Previous studies have shown that deep learning is very effective in detecting known attacks.However,when facing unknown attacks,models such as Deep Neural Networks(DNN)combined with Long Short-Term Memory(LSTM),Convolutional Neural Networks(CNN)combined with LSTM,and so on are built by simple stacking,which has the problems of feature loss,low efficiency,and low accuracy.Therefore,this paper proposes an autonomous detectionmodel for Distributed Denial of Service attacks,Multi-Scale Convolutional Neural Network-Bidirectional Gated Recurrent Units-Single Headed Attention(MSCNN-BiGRU-SHA),which is based on a Multistrategy Integrated Zebra Optimization Algorithm(MI-ZOA).The model undergoes training and testing with the CICDDoS2019 dataset,and its performance is evaluated on a new GINKS2023 dataset.The hyperparameters for Conv_filter and GRU_unit are optimized using the Multi-strategy Integrated Zebra Optimization Algorithm(MIZOA).The experimental results show that the test accuracy of the MSCNN-BiGRU-SHA model based on the MIZOA proposed in this paper is as high as 0.9971 in the CICDDoS 2019 dataset.The evaluation accuracy of the new dataset GINKS2023 created in this paper is 0.9386.Compared to the MSCNN-BiGRU-SHA model based on the Zebra Optimization Algorithm(ZOA),the detection accuracy on the GINKS2023 dataset has improved by 5.81%,precisionhas increasedby 1.35%,the recallhas improvedby 9%,and theF1scorehas increasedby 5.55%.Compared to the MSCNN-BiGRU-SHA models developed using Grid Search,Random Search,and Bayesian Optimization,the MSCNN-BiGRU-SHA model optimized with the MI-ZOA exhibits better performance in terms of accuracy,precision,recall,and F1 score. 展开更多
关键词 Distributed denial of service attack intrusion detection deep learning zebra optimization algorithm multi-strategy integrated zebra optimization algorithm
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Mole-inspired Forepaw Design and Optimization Based on Resistive Force Theory 被引量:1
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作者 Tao Zhang Zhaofeng Liang +8 位作者 Hongmin Zheng Zibiao Chen Kunquan Zheng Ran Xu Jiabin Liu Haifei Zhu Yisheng Guan Kun Xu Xilun Ding 《Journal of Bionic Engineering》 2025年第1期171-180,共10页
Moles exhibit highly effective capabilities due to their unique body structures and digging techniques,making them ideal models for biomimetic research.However,a major challenge for mole-inspired robots lies in overco... Moles exhibit highly effective capabilities due to their unique body structures and digging techniques,making them ideal models for biomimetic research.However,a major challenge for mole-inspired robots lies in overcoming resistance in granular media when burrowing with forelimbs.In the absence of effective forepaw design strategies,most robotic designs rely on increased power to enhance performance.To address this issue,this paper employs Resistive Force Theory to optimize mole-inspired forepaws,aiming to enhance burrowing efficiency.By analyzing the relationship between geometric parameters and burrowing forces,we propose several forepaw design variations.Through granular resistance assessments,an effective forepaw configuration is identified and further refined using parameters such as longitudinal and transverse curvature.Subsequently,the Particle Swarm Optimization algorithm is applied to determine the optimal forepaw design.In force-loading tests,the optimized forepaw demonstrated a 79.44%reduction in granular lift force and a 22.55%increase in propulsive force compared with the control group.In robotic burrowing experiments,the optimized forepaw achieved the longest burrow displacement(179.528 mm)and the lowest burrowing lift force(0.9355 mm/s),verifying its effectiveness in reducing the lift force and enhancing the propulsive force. 展开更多
关键词 Resistive force theory mole-inspired forepaw design Structural optimization Bioinspired robot
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Prediction of Shear Bond Strength of Asphalt Concrete Pavement Using Machine Learning Models and Grid Search Optimization Technique
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作者 Quynh-Anh Thi Bui Dam Duc Nguyen +2 位作者 Hiep Van Le Indra Prakash Binh Thai Pham 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期691-712,共22页
Determination of Shear Bond strength(SBS)at interlayer of double-layer asphalt concrete is crucial in flexible pavement structures.The study used three Machine Learning(ML)models,including K-Nearest Neighbors(KNN),Ext... Determination of Shear Bond strength(SBS)at interlayer of double-layer asphalt concrete is crucial in flexible pavement structures.The study used three Machine Learning(ML)models,including K-Nearest Neighbors(KNN),Extra Trees(ET),and Light Gradient Boosting Machine(LGBM),to predict SBS based on easily determinable input parameters.Also,the Grid Search technique was employed for hyper-parameter tuning of the ML models,and cross-validation and learning curve analysis were used for training the models.The models were built on a database of 240 experimental results and three input variables:temperature,normal pressure,and tack coat rate.Model validation was performed using three statistical criteria:the coefficient of determination(R2),the Root Mean Square Error(RMSE),and the mean absolute error(MAE).Additionally,SHAP analysis was also used to validate the importance of the input variables in the prediction of the SBS.Results show that these models accurately predict SBS,with LGBM providing outstanding performance.SHAP(Shapley Additive explanation)analysis for LGBM indicates that temperature is the most influential factor on SBS.Consequently,the proposed ML models can quickly and accurately predict SBS between two layers of asphalt concrete,serving practical applications in flexible pavement structure design. 展开更多
关键词 Shear bond asphalt pavement grid search optimization machine learning
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Max-Min Security Rate Optimization in STAR-RIS Aided Secure MIMO Systems
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作者 HUANG Jinhao MIAO Ling +1 位作者 SUO Long ZHOU Wen 《电讯技术》 北大核心 2025年第10期1657-1664,共8页
The simultaneous transmitting and reflecting reconfigurable intelligent surface(STAR-RIS)can independently adjust surface’s reflection and transmission coefficients so as to enhance space coverage.For a multiple-inpu... The simultaneous transmitting and reflecting reconfigurable intelligent surface(STAR-RIS)can independently adjust surface’s reflection and transmission coefficients so as to enhance space coverage.For a multiple-input multiple-output(MIMO)communication system with a STAR-RIS,a base station(BS),an eavesdropper,and multiple users,the system security rate is studied.A joint design of the power allocation at the transmitter and phase shift matrices for reflection and transmission at the STAR-RIS is conducted,in order to maximize the worst achievable security data rate(ASDR).Since the problem is nonconvex and hence challenging,a particle swarm optimization(PSO)based algorithm is developed to tackle the problem.Both the cases of continuous and discrete phase shift matrices at the STAR-RIS are considered.Simulation results demonstrate the effectiveness of the proposed algorithm and shows the benefits of using STAR-RIS in MIMO mutliuser systems. 展开更多
关键词 multiple-input multiple-output(MImo) reflecting reconfigurable intelligent surface(STAR-RIS) particle swarm optimization(PSO) max-min security rate optimization
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铸态00Cr25Ni7Mo4N的热变形行为及其微观组织研究
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作者 郭旭军 田继红 +3 位作者 陈慧琴 陈国豪 刘利军 温凯 《塑性工程学报》 北大核心 2026年第1期180-189,共10页
为探究铸态超级双相不锈钢00Cr25Ni7Mo4N的高温变形行为,采用Gleeble-3800热/力模拟试验机进行热压缩实验,研究了铸态超级双相不锈钢00Cr25Ni7Mo4N在变形温度为1000~1200℃、应变速率为0.001~1 s^(-1)、真应变为0.916条件下的热变形行为... 为探究铸态超级双相不锈钢00Cr25Ni7Mo4N的高温变形行为,采用Gleeble-3800热/力模拟试验机进行热压缩实验,研究了铸态超级双相不锈钢00Cr25Ni7Mo4N在变形温度为1000~1200℃、应变速率为0.001~1 s^(-1)、真应变为0.916条件下的热变形行为,并绘制真应力-真应变曲线。实验结果表明,00Cr25Ni7Mo4N不锈钢在高变形温度和低应变速率下更容易发生动态再结晶。通过对实验数据进行多元线性拟合计算,得到了00Cr25Ni7Mo4N不锈钢的热变形激活能,建立了00Cr25Ni7Mo4N不锈钢的高温塑性本构方程。使用电子背散射衍射技术观察到铁素体在各种变形条件下均发生了动态再结晶,其动态软化机制为连续动态再结晶;而奥氏体的动态软化机制受变形温度的影响,当变形温度较低时,动态回复是奥氏体相的主要软化机制,伴随着变形温度的升高,又呈现出非连续动态再结晶。 展开更多
关键词 00Cr25Ni7mo4N不锈钢 本构方程 动态回复 连续动态再结晶 非连续动态再结晶
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Grid-Connected/Islanded Switching Control Strategy for Photovoltaic Storage Hybrid Inverters Based on Modified Chimpanzee Optimization Algorithm
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作者 Chao Zhou Narisu Wang +1 位作者 Fuyin Ni Wenchao Zhang 《Energy Engineering》 EI 2025年第1期265-284,共20页
Uneven power distribution,transient voltage,and frequency deviations are observed in the photovoltaic storage hybrid inverter during the switching between grid-connected and island modes.In response to these issues,th... Uneven power distribution,transient voltage,and frequency deviations are observed in the photovoltaic storage hybrid inverter during the switching between grid-connected and island modes.In response to these issues,this paper proposes a grid-connected/island switching control strategy for photovoltaic storage hybrid inverters based on the modified chimpanzee optimization algorithm.The proposed strategy incorporates coupling compensation and power differentiation elements based on the traditional droop control.Then,it combines the angular frequency and voltage amplitude adjustments provided by the phase-locked loop-free pre-synchronization control strategy.Precise pre-synchronization is achieved by regulating the virtual current to zero and aligning the photovoltaic storage hybrid inverter with the grid voltage.Additionally,two novel operators,learning and emotional behaviors are introduced to enhance the optimization precision of the chimpanzee algorithm.These operators ensure high-precision and high-reliability optimization of the droop control parameters for photovoltaic storage hybrid inverters.A Simulink model was constructed for simulation analysis,which validated the optimized control strategy’s ability to evenly distribute power under load transients.This strategy effectively mitigated transient voltage and current surges during mode transitions.Consequently,seamless and efficient switching between gridconnected and island modes was achieved for the photovoltaic storage hybrid inverter.The enhanced energy utilization efficiency,in turn,offers robust technical support for grid stability. 展开更多
关键词 Photovoltaic storage hybrid inverters modified chimpanzee optimization algorithm droop control seamless switching
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Convex Optimization-Based Model Predictive Control for Mars Ascent Vehicle Guidance System
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作者 Kun Li Yanning Guo +2 位作者 Guangtao Ran Yueyong Lyu Guangfu Ma 《IEEE/CAA Journal of Automatica Sinica》 2025年第10期2159-2161,共3页
Dear Editor,This letter proposes a convex optimization-based model predictive control(MPC)autonomous guidance method for the Mars ascent vehicle(MAV).We use the modified chebyshev-picard iteration(MCPI)to solve optimi... Dear Editor,This letter proposes a convex optimization-based model predictive control(MPC)autonomous guidance method for the Mars ascent vehicle(MAV).We use the modified chebyshev-picard iteration(MCPI)to solve optimization sub-problems within the MPC framework,eliminating the dynamic constraints in solving the optimal control problem and enhancing the convergence performance of the algorithm.Moreover,this method can repeatedly perform trajectory optimization calculations at a high frequency,achieving timely correction of the optimal control command.Numerical simulations demonstrate that the method can satisfy the requirements of rapid computation and reliability for the MAV system when considering uncertainties and perturbations. 展开更多
关键词 guidance method optimal control problem model predictive mars ascent vehicle mav we Mars ascent vehicle convex optimization trajectory optimization enhancing convergence performance
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Modeling and Layout Optimization of Bio-inspired Swarm Vigilance Tasks
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作者 Ruyi ZHENG Zhenxin MU +3 位作者 Shihan KONG Yingnan LI Fang WU Junzhi YU 《Artificial Intelligence Science and Engineering》 2025年第3期229-238,共10页
This paper considers the swarm vigilance problem for multi-agent systems(MAS),where multiple agents are deployed within a rectangular region for perception-based vigilance.There are two main challenges,namely the task... This paper considers the swarm vigilance problem for multi-agent systems(MAS),where multiple agents are deployed within a rectangular region for perception-based vigilance.There are two main challenges,namely the task allocation for vigilance roles and the coverage planning of the perception ranges.Firstly,vigilance behavioral patterns and processes in animal populations within natural habitats are investigated.Inspired by these biological vigilance behaviors,an efficient vigilance task allocation model for MAS is proposed.Secondly,the subsequent optimization of task layouts can achieve efficient surveillance coverage with fewer agents,minimizing resource consumption.Thirdly,an improved particle swarm optimization(IPSO)algorithm is proposed,which incorporates fitness-driven adaptive inertia weight dynamics.According to simulation analysis and comparative studies,optimal parameter configurations for genetic algorithm(GA)and IPSO are determined.Finally,the results indicate the proposed IPSO's superior performance to both GA and standard particle swarm optimization(PSO)in vigilance task allocation optimization,with satisfying advantages in computational efficiency and solution quality. 展开更多
关键词 multi-agent systems swarm vigilance task optimization bio-inspired control particle swarm optimization
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Mordukhovich Subdifferential Optimization Framework for Multi-Criteria Voice Cloning of Pathological Speech
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作者 Rytis Maskeliūnas Robertas Damaševicius +3 位作者 Audrius Kulikajevas Kipras Pribuišis Nora Ulozaite-Staniene Virgilijus Uloza 《Computer Modeling in Engineering & Sciences》 2025年第12期4203-4223,共21页
This study introduces a novel voice cloning framework driven by Mordukhovich Subdifferential Optimization(MSO)to address the complex multi-objective challenges of pathological speech synthesis in underresourced Lithua... This study introduces a novel voice cloning framework driven by Mordukhovich Subdifferential Optimization(MSO)to address the complex multi-objective challenges of pathological speech synthesis in underresourced Lithuanian language with unique phonemes not present in most pre-trained models.Unlike existing voice synthesis models that often optimize for a single objective or are restricted to major languages,our approach explicitly balances four competing criteria:speech naturalness,speaker similarity,computational efficiency,and adaptability to pathological voice patterns.We evaluate four model configurations combining Lithuanian and English encoders,synthesizers,and vocoders.The hybrid model(English encoder,Lithuanian synthesizer,English vocoder),optimized via MSO,achieved the highest Mean Opinion Score(MOS)of 4.3 and demonstrated superior intelligibility and speaker fidelity.The results confirm that MSO enables effective navigation of trade-offs in multilingual pathological voice cloning,offering a scalable path toward high-quality voice restoration in clinical speech applications.This work represents the first integration of Mordukhovich optimization into pathological TTS,setting a new benchmark for speech synthesis under clinical and linguistic constraints. 展开更多
关键词 mordukhovich subdifferential optimization multi-objective optimization alaryngeal voice reconstruction
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Integrated optimization of reservoir production and layer configurations using relational and regression machine learning models
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作者 Qin-Yang Dai Li-Ming Zhang +6 位作者 Kai Zhang Hao Hao Guo-Dong Chen Xia Yan Pi-Yang Liu Bao-Bin Zhang Chen-Yang Wang 《Petroleum Science》 2025年第9期3745-3759,共15页
This study introduces a novel approach to addressing the challenges of high-dimensional variables and strong nonlinearity in reservoir production and layer configuration optimization.For the first time,relational mach... This study introduces a novel approach to addressing the challenges of high-dimensional variables and strong nonlinearity in reservoir production and layer configuration optimization.For the first time,relational machine learning models are applied in reservoir development optimization.Traditional regression-based models often struggle in complex scenarios,but the proposed relational and regression-based composite differential evolution(RRCODE)method combines a Gaussian naive Bayes relational model with a radial basis function network regression model.This integration effectively captures complex relationships in the optimization process,improving both accuracy and convergence speed.Experimental tests on a multi-layer multi-channel reservoir model,the Egg reservoir model,and a real-field reservoir model(the S reservoir)demonstrate that RRCODE significantly reduces water injection and production volumes while increasing economic returns and cumulative oil recovery.Moreover,the surrogate models employed in RRCODE exhibit lightweight characteristics with low computational overhead.These results highlight RRCODE's superior performance in the integrated optimization of reservoir production and layer configurations,offering more efficient and economically viable solutions for oilfield development. 展开更多
关键词 Surrogate model Reservoir management Evolutionary algorithm Joint optimization Layer configuration Production optimization Relational learning
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Research on the Optimal Scheduling Model of Energy Storage Plant Based on Edge Computing and Improved Whale Optimization Algorithm
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作者 Zhaoyu Zeng Fuyin Ni 《Energy Engineering》 2025年第3期1153-1174,共22页
Energy storage power plants are critical in balancing power supply and demand.However,the scheduling of these plants faces significant challenges,including high network transmission costs and inefficient inter-device ... Energy storage power plants are critical in balancing power supply and demand.However,the scheduling of these plants faces significant challenges,including high network transmission costs and inefficient inter-device energy utilization.To tackle these challenges,this study proposes an optimal scheduling model for energy storage power plants based on edge computing and the improved whale optimization algorithm(IWOA).The proposed model designs an edge computing framework,transferring a large share of data processing and storage tasks to the network edge.This architecture effectively reduces transmission costs by minimizing data travel time.In addition,the model considers demand response strategies and builds an objective function based on the minimization of the sum of electricity purchase cost and operation cost.The IWOA enhances the optimization process by utilizing adaptive weight adjustments and an optimal neighborhood perturbation strategy,preventing the algorithm from converging to suboptimal solutions.Experimental results demonstrate that the proposed scheduling model maximizes the flexibility of the energy storage plant,facilitating efficient charging and discharging.It successfully achieves peak shaving and valley filling for both electrical and heat loads,promoting the effective utilization of renewable energy sources.The edge-computing framework significantly reduces transmission delays between energy devices.Furthermore,IWOA outperforms traditional algorithms in optimizing the objective function. 展开更多
关键词 Energy storage plant edge computing optimal energy scheduling improved whale optimization algorithm
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