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An Overall Optimization Model Using Metaheuristic Algorithms for the CNN-Based IoT Attack Detection Problem
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作者 Le Thi Hong Van Le Duc Thuan +1 位作者 Pham Van Huong Nguyen Hieu Minh 《Computers, Materials & Continua》 2026年第4期1934-1964,共31页
Optimizing convolutional neural networks(CNNs)for IoT attack detection remains a critical yet challenging task due to the need to balance multiple performance metrics beyond mere accuracy.This study proposes a unified... Optimizing convolutional neural networks(CNNs)for IoT attack detection remains a critical yet challenging task due to the need to balance multiple performance metrics beyond mere accuracy.This study proposes a unified and flexible optimization framework that leverages metaheuristic algorithms to automatically optimize CNN configurations for IoT attack detection.Unlike conventional single-objective approaches,the proposed method formulates a global multi-objective fitness function that integrates accuracy,precision,recall,and model size(speed/model complexity penalty)with adjustable weights.This design enables both single-objective and weightedsum multi-objective optimization,allowing adaptive selection of optimal CNN configurations for diverse deployment requirements.Two representativemetaheuristic algorithms,GeneticAlgorithm(GA)and Particle Swarm Optimization(PSO),are employed to optimize CNNhyperparameters and structure.At each generation/iteration,the best configuration is selected as themost balanced solution across optimization objectives,i.e.,the one achieving themaximum value of the global objective function.Experimental validation on two benchmark datasets,Edge-IIoT and CIC-IoT2023,demonstrates that the proposed GA-and PSO-based models significantly enhance detection accuracy(94.8%–98.3%)and generalization compared with manually tuned CNN configurations,while maintaining compact architectures.The results confirm that the multi-objective framework effectively balances predictive performance and computational efficiency.This work establishes a generalizable and adaptive optimization strategy for deep learning-based IoT attack detection and provides a foundation for future hybrid metaheuristic extensions in broader IoT security applications. 展开更多
关键词 Genetic algorithm(GA) particle swarm optimization(PSO) multi-objective optimization convolutional neural network—CNN IoT attack detection metaheuristic optimization CNN configuration
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Advanced Meta-Heuristic Optimization for Accurate Photovoltaic Model Parameterization:A High-Accuracy Estimation Using Spider Wasp Optimization
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作者 Sarah M.Alhammad Diaa Salama AbdElminaam +1 位作者 Asmaa Rizk Ibrahim Ahmed Taha 《Computers, Materials & Continua》 2026年第3期2269-2303,共35页
Accurate parameter extraction of photovoltaic(PV)models plays a critical role in enabling precise performance prediction,optimal system sizing,and effective operational control under diverse environmental conditions.W... Accurate parameter extraction of photovoltaic(PV)models plays a critical role in enabling precise performance prediction,optimal system sizing,and effective operational control under diverse environmental conditions.While a wide range of metaheuristic optimisation techniques have been applied to this problem,many existing methods are hindered by slow convergence rates,susceptibility to premature stagnation,and reduced accuracy when applied to complex multi-diode PV configurations.These limitations can lead to suboptimal modelling,reducing the efficiency of PV system design and operation.In this work,we propose an enhanced hybrid optimisation approach,the modified Spider Wasp Optimization(mSWO)with Opposition-Based Learning algorithm,which integrates the exploration and exploitation capabilities of the Spider Wasp Optimization(SWO)metaheuristic with the diversityenhancing mechanism of Opposition-Based Learning(OBL).The hybridisation is designed to dynamically expand the search space coverage,avoid premature convergence,and improve both convergence speed and precision in highdimensional optimisation tasks.The mSWO algorithm is applied to three well-established PV configurations:the single diode model(SDM),the double diode model(DDM),and the triple diode model(TDM).Real experimental current-voltage(I-V)datasets from a commercial PV module under standard test conditions(STC)are used for evaluation.Comparative analysis is conducted against eighteen advanced metaheuristic algorithms,including BSDE,RLGBO,GWOCS,MFO,EO,TSA,and SCA.Performance metrics include minimum,mean,and maximum root mean square error(RMSE),standard deviation(SD),and convergence behaviour over 30 independent runs.The results reveal that mSWO consistently delivers superior accuracy and robustness across all PV models,achieving the lowest RMSE values of 0.000986022(SDM),0.000982884(DDM),and 0.000982529(TDM),with minimal SD values,indicating remarkable repeatability.Convergence analyses further show that mSWO reaches optimal solutions more rapidly and with fewer oscillations than all competing methods,with the performance gap widening as model complexity increases.These findings demonstrate that mSWO provides a scalable,computationally efficient,and highly reliable framework for PV parameter extraction.Its adaptability to models of growing complexity suggests strong potential for broader applications in renewable energy systems,including performance monitoring,fault detection,and intelligent control,thereby contributing to the optimisation of next-generation solar energy solutions. 展开更多
关键词 modified Spider Wasp Optimizer(mSWO) photovoltaic(PV)modeling meta-heuristic optimization solar energy parameter estimation renewable energy technologies
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Design and optimization of a high-efficiency current-biased reverse load modulated power amplifier with impedance and performance constraints
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作者 Zhongpeng NI Heng ZHANG +4 位作者 Jing XIA Wence ZHANG Wa KONG Chao YU Xiaowei ZHU 《ENGINEERING Information Technology & Electronic Engineering》 2026年第1期71-79,共9页
We propose an optimization method based on evolutionary computation for the design of broadband high-efficiency current-biased reverse load-modulation power amplifiers(CB-RLM PAs).First,given the reverse load-modulati... We propose an optimization method based on evolutionary computation for the design of broadband high-efficiency current-biased reverse load-modulation power amplifiers(CB-RLM PAs).First,given the reverse load-modulation characteristics of CB-RLM PAs,a comprehensive objective function is proposed that combines multi-state impedance trajectory constraints with in-band performance deviations.For the saturation and 6 dB power back-off(PBO)states,approximately optimal impedance regions on the Smith chart are derived using impedance constraint circles based on load-pull simulations.These regions are used together with in-band performance deviations(e.g.,saturated efficiency,6 dB PBO efficiency,and saturated output power)for matching network optimization and design.Second,a multi-objective evolutionary algorithm based on decomposition with adaptive weights,neighborhood,and global replacement is integrated with harmonic balance simulations to optimize design parameters and evaluate performance.Finally,to validate the proposed method,a broadband CB-RLM PA operating from 0.6 to 1.8 GHz is designed and fabricated.Measurement results show that the efficiencies at saturation,6 dB PBO,and 8 dB PBO all exceed 43.6%,with saturated output power being maintained at 40.9–41.5 dBm,which confirms the feasibility and effectiveness of the proposed broadband high-efficiency CB-RLM PA optimization and design approach. 展开更多
关键词 Current-biased reverse load-modulation Broadband High efficiency Power amplifier optimization
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MDMOSA:Multi-Objective-Oriented Dwarf Mongoose Optimization for Cloud Task Scheduling
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作者 Olanrewaju Lawrence Abraham Md Asri Ngadi +1 位作者 Johan Bin Mohamad Sharif Mohd Kufaisal Mohd Sidik 《Computers, Materials & Continua》 2026年第3期2062-2096,共35页
Task scheduling in cloud computing is a multi-objective optimization problem,often involving conflicting objectives such as minimizing execution time,reducing operational cost,and maximizing resource utilization.Howev... Task scheduling in cloud computing is a multi-objective optimization problem,often involving conflicting objectives such as minimizing execution time,reducing operational cost,and maximizing resource utilization.However,traditional approaches frequently rely on single-objective optimization methods which are insufficient for capturing the complexity of such problems.To address this limitation,we introduce MDMOSA(Multi-objective Dwarf Mongoose Optimization with Simulated Annealing),a hybrid that integrates multi-objective optimization for efficient task scheduling in Infrastructure-as-a-Service(IaaS)cloud environments.MDMOSA harmonizes the exploration capabilities of the biologically inspired Dwarf Mongoose Optimization(DMO)with the exploitation strengths of Simulated Annealing(SA),achieving a balanced search process.The algorithm aims to optimize task allocation by reducing makespan and financial cost while improving system resource utilization.We evaluate MDMOSA through extensive simulations using the real-world Google Cloud Jobs(GoCJ)dataset within the CloudSim environment.Comparative analysis against benchmarked algorithms such as SMOACO,MOTSGWO,and MFPAGWO reveals that MDMOSA consistently achieves superior performance in terms of scheduling efficiency,cost-effectiveness,and scalability.These results confirm the potential of MDMOSA as a robust and adaptable solution for resource scheduling in dynamic and heterogeneous cloud computing infrastructures. 展开更多
关键词 Cloud computing MULTI-OBJECTIVE task scheduling dwarf mongoose optimization METAHEURISTIC
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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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Dual Layer Source Grid Load Storage Collaborative Planning Model Based on Benders Decomposition: Distribution Network Optimization Considering Low-Carbon and Economy
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作者 Jun Guo Maoyuan Chen +2 位作者 Yuyang Li Sibo Feng Guangyu Fu 《Energy Engineering》 2026年第2期104-133,共30页
Theauthor proposes a dual layer source grid load storage collaborative planning model based on Benders decomposition to optimize the low-carbon and economic performance of the distribution network.The model plans the ... Theauthor proposes a dual layer source grid load storage collaborative planning model based on Benders decomposition to optimize the low-carbon and economic performance of the distribution network.The model plans the configuration of photovoltaic(3.8 MW),wind power(2.5 MW),energy storage(2.2 MWh),and SVC(1.2 Mvar)through interaction between upper and lower layers,and modifies lines 2–3,8–9,etc.to improve transmission capacity and voltage stability.The author uses normal distribution and Monte Carlo method to model load uncertainty,and combines Weibull distribution to describe wind speed characteristics.Compared to the traditional three-layer model(TLM),Benders decomposition-based two-layer model(BLBD)has a 58.1%reduction in convergence time(5.36 vs.12.78 h),a 51.1%reduction in iteration times(23 vs.47 times),a 8.07%reduction in total cost(12.436 vs.13.528 million yuan),and a 9.62%reduction in carbon emissions(12,456 vs.13,782 t).After optimization,the peak valley difference decreased from4.1 to 2.9MW,the renewable energy consumption rate reached 93.4%,and the energy storage efficiency was 87.6%.Themodel has been validated in the IEEE 33 node system,demonstrating its superiority in terms of economy,low-carbon,and reliability. 展开更多
关键词 Benders decomposition source grid load storage distribution network planning low-carbon economy optimization model
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Optimization of the frequency offset increment of FDA-MIMO based on cuckoo search algorithm
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作者 WANG Bo ZHAO Yu +2 位作者 LI Yonglin YANG Rennong XUE Junjie 《Journal of Systems Engineering and Electronics》 2026年第1期157-170,共14页
Frequency diverse array multiple-input multiple-output(FDA-MIMO)radar has gained considerable research attention due to its ability to effectively counter active repeater deception jamming in complex electromagnetic e... Frequency diverse array multiple-input multiple-output(FDA-MIMO)radar has gained considerable research attention due to its ability to effectively counter active repeater deception jamming in complex electromagnetic environments.The effectiveness of interference suppression by FDA-MIMO is limited by the inherent range-angle coupling issue in the FDA beampattern.Existing literature primarily focuses on control methods for FDA-MIMO radar beam direction under the assumption of static beampatterns,with insufficient exploration of techniques for managing nonstationary beam directions.To address this gap,this paper initially introduces the FDA-MIMO signal model and the calculation formula for the FDA-MIMO array output using the minimum variance distortionless response(MVDR)beamformer.Building on this,the problem of determining the optimal frequency offset for the FDA is rephrased as a convex optimization problem,which is then resolved using the cuckoo search(CS)algorithm.Simulations confirm the effectiveness of the proposed approach,showing that the frequency offsets obtained through the CS algorithm can create a dot-shaped beam direction at the target location while effectively suppressing interference signals within the mainlobe. 展开更多
关键词 frequency diverse array multiple-input multiple-output(FDA-MImo) convex optimization cuckoo search algorithm beampattern
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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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An Improved Variant of Multi-Population Cooperative Constrained Multi-Objective Optimization(MCCMO)for Multi-Objective Optimization Problem
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作者 Muhammad Waqar Khan Adnan Ahmed Siddiqui Syed Sajjad Hussain Rizvi 《Computers, Materials & Continua》 2026年第2期1874-1888,共15页
The multi-objective optimization problems,especially in constrained environments such as power distribution planning,demand robust strategies for discovering effective solutions.This work presents the improved variant... The multi-objective optimization problems,especially in constrained environments such as power distribution planning,demand robust strategies for discovering effective solutions.This work presents the improved variant of the Multi-population Cooperative Constrained Multi-Objective Optimization(MCCMO)Algorithm,termed Adaptive Diversity Preservation(ADP).This enhancement is primarily focused on the improvement of constraint handling strategies,local search integration,hybrid selection approaches,and adaptive parameter control.Theimproved variant was experimented on with the RWMOP50 power distribution systemplanning benchmark.As per the findings,the improved variant outperformed the original MCCMO across the eleven performance metrics,particularly in terms of convergence speed,constraint handling efficiency,and solution diversity.The results also establish that MCCMOADP consistently delivers substantial performance gains over the baseline MCCMO,demonstrating its effectiveness across performancemetrics.The new variant also excels atmaintaining the balanced trade-off between exploration and exploitation throughout the search process,making it especially suitable for complex optimization problems in multiconstrained power systems.These enhancements make MCCMO-ADP a valuable and promising candidate for handling problems such as renewable energy scheduling,logistics planning,and power system optimization.Future work will benchmark the MCCMO-ADP against widely recognized algorithms such as NSGA-Ⅱ,NSGA-Ⅲ,and MOEA/D and will also extend its validation to large-scale real-world optimization domains to further consolidate its generalizability. 展开更多
关键词 MCCmo algorithms adaptive diversity preservation RWmoP50 power distribution system multi-modal multi objective optimization evolutionary algorithm multi objective problem
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V、Nb、Ti微合金元素在低Mo耐火钢中强化机理研究
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作者 万荣春 《船舶职业教育》 2026年第1期49-52,共4页
通过观察两种不同V、Nb、Ti微合金元素含量的Q355级别低Mo(小于0.30 wt.%)耐火钢在不同变形量下滑移带分布特征,结合试验钢显微组织与力学性能,分析研究V、Nb、Ti微合金元素在耐火钢中的强化机理。试验结果表明,V、Nb、Ti微合金元素的加... 通过观察两种不同V、Nb、Ti微合金元素含量的Q355级别低Mo(小于0.30 wt.%)耐火钢在不同变形量下滑移带分布特征,结合试验钢显微组织与力学性能,分析研究V、Nb、Ti微合金元素在耐火钢中的强化机理。试验结果表明,V、Nb、Ti微合金元素的加入,可以增加试验钢的贝氏体体积分数,同时增加铁素体中的析出相和位错密度。V、Nb、Ti微合金元素在耐火钢中的强化机理主要表现在两方面:一是通过析出强化和增加位错密度,强化铁素体组织;二是通过增加贝氏体体积分数,实现贝氏体相变强化,同时强化其周围贝氏体/铁素体复合组织。 展开更多
关键词 V、Nb、Ti mo耐火钢 强化机理
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纳米压痕结合有限元法确定Mo掺杂ZnO薄膜的横观各向同性弹性力学参数
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作者 李召阳 李国友 +4 位作者 潘胡江 陈智勇 宋伟志 李彬 宋亚虎 《中国测试》 北大核心 2026年第1期60-68,共9页
该文提出一种结合有限元分析与纳米压痕实验的方法,研究ZnO基薄膜的横观各向同性力学性能。首先,基于Abaqus软件,通过有限元模拟纳米压痕过程,构建ZnO基薄膜的横观各向同性力学模型,并求解最大加载力F_(max)、加载曲线指数x与薄膜弹性... 该文提出一种结合有限元分析与纳米压痕实验的方法,研究ZnO基薄膜的横观各向同性力学性能。首先,基于Abaqus软件,通过有限元模拟纳米压痕过程,构建ZnO基薄膜的横观各向同性力学模型,并求解最大加载力F_(max)、加载曲线指数x与薄膜弹性参数之间的无量纲函数关系。然后,通过纳米压痕实验获取薄膜的实验数据,结合柔度矩阵分析,计算ZnO和MZO薄膜在纳米压痕过程中的应力-应变关系以及弹性模量和切变模量。结果表明:Mo掺杂对薄膜的力学性能有显著影响,适量掺Mo可提高MZO薄膜的弹性模量,并减小切变模量的各向异性;然而,过量掺Mo会导致弹性模量下降,切变模量上升。该方法可为薄膜材料力学性能的研究提供一种新的思路,能够有效评估不同掺杂浓度下薄膜的稳定性和可靠性。 展开更多
关键词 mo掺杂ZnO 薄膜 横观各向同性 弹性模量 切变模量
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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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电化学抛光对激光粉末床熔融纯Mo降解行为的影响
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作者 李旭卿 张士达 +3 位作者 魏福兰 姜秀丽 张建华 尹瀛月 《金属加工(热加工)》 2026年第1期51-58,共8页
激光粉末床熔融(Laser Powder Bed Fusion,LPBF)技术是定制化多孔纯Mo结构的重要技术。然而,LPBF成形纯Mo试样仍面临表面粗糙度值高及耐蚀性差等问题。电化学抛光(Electrochemical Polishing,ECP)是LPBF成形纯Mo的主要环保型后处理工艺... 激光粉末床熔融(Laser Powder Bed Fusion,LPBF)技术是定制化多孔纯Mo结构的重要技术。然而,LPBF成形纯Mo试样仍面临表面粗糙度值高及耐蚀性差等问题。电化学抛光(Electrochemical Polishing,ECP)是LPBF成形纯Mo的主要环保型后处理工艺。研究了不同ECP抛光状态对LPBF成形纯Mo的表面粗糙度及降解特性的影响。结果表明:经电化学抛光处理后,试样表面粗糙度由4.55μm显著降低至1.05μm;相比原始态试样,抛光后试样腐蚀电流密度降低了78.4%。失重率从大到小顺序为:原始态>半抛光>抛光,且随着浸泡时间增加,失重率逐渐增加。溶液pH值波动≤0.5,验证了降解过程未引发局部酸化,符合生物医用材料要求。通过采用ECP处理Mo基材料表面,为合理调控其植入体的降解行为及降解速率的均匀性提供了重要理论依据。 展开更多
关键词 mo 激光粉末床熔融(LPBF) 电化学抛光 降解行为
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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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基于PSO-SMO的分布式驱动车辆轮胎力级联估计
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作者 王姝 杨再杰 +1 位作者 赵轩 吕洋 《重庆理工大学学报(自然科学)》 北大核心 2026年第1期27-35,共9页
针对传统以轮胎模型为基础的轮胎力估计依赖准确的轮胎模型和路面附着系数等参数的缺点,提出一种基于粒子群优化滑模算法(PSO-SMO)的轮胎力级联估计器。首先,考虑车辆运动时的质心偏移和悬架运动,建立车辆载荷转移模型估计轮胎垂向力;同... 针对传统以轮胎模型为基础的轮胎力估计依赖准确的轮胎模型和路面附着系数等参数的缺点,提出一种基于粒子群优化滑模算法(PSO-SMO)的轮胎力级联估计器。首先,考虑车辆运动时的质心偏移和悬架运动,建立车辆载荷转移模型估计轮胎垂向力;同时,以车轮动力学模型为基础,基于PSO-SMO估计算法设计轮胎纵向力估计器。在此基础上,以纵向力和垂向力估计值为已知信息,结合前轮转角、横摆角速度等参数,基于PSO-SMO估计算法实现侧向力估计。最后在Carsim-Simulink联合仿真平台下进行仿真试验。结果表明,在不同行驶工况下,该估计器能够有效估计轮胎力,相比传统观测器收敛速度更快,估计精度更高,尤其是在附着系数变化的路面下鲁棒性更强。 展开更多
关键词 质心偏移 粒子群优化算法 滑模观测器 轮胎力
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