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PROMPTx-PE:Adaptive Optimization of Prompt Engineering Strategies for Accuracy and Robustness in Large Language Models
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作者 Talha Farooq Khan Fahad Ali +2 位作者 Majid Hussain Lal Khan Hsien-Tsung Chang 《Computers, Materials & Continua》 2026年第5期685-715,共31页
The outstanding growth in the applications of large language models(LLMs)demonstrates the significance of adaptive and efficient prompt engineering tactics.The existing methods may not be variable,vigorous and streaml... The outstanding growth in the applications of large language models(LLMs)demonstrates the significance of adaptive and efficient prompt engineering tactics.The existing methods may not be variable,vigorous and streamlined in different domains.The offered study introduces an immediate optimization outline,named PROMPTx-PE,that is going to yield a greater level of precision and strength when it comes to the assignments that are premised on LLM.The proposed systemfeatures a timely selection schemewhich is informed by reinforcement learning,a contextual layer and a dynamic weighting module which is regulated by Lyapunov-based stability guidelines.The PROMPTx-PE dynamically varies the exploration and exploitation of the prompt space,depending on real-time feedback and multi-objective reward development.Extensive testing on both benchmark(GLUE,SuperGLUE)and domain-specific data(Healthcare-QA and Industrial-NER)demonstrates a large best performance to be 89.4%and a strong robustness disconnect with under 3%computation expense.The results confirm the effectiveness,consistency,and scalability of PROMPTx-PE as a platform of adaptive prompt engineering based on recent uses of LLMs. 展开更多
关键词 Prompt engineering large language models adaptive optimization robustness multi-objective optimization reinforcement learning natural language processing
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Adversarial robustness evaluation based on classification confidence-based confusion matrix
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作者 YAO Xuemei SUN Jianbin +1 位作者 LI Zituo YANG Kewei 《Journal of Systems Engineering and Electronics》 2026年第1期184-196,共13页
Evaluating the adversarial robustness of classification algorithms in machine learning is a crucial domain.However,current methods lack measurable and interpretable metrics.To address this issue,this paper introduces ... Evaluating the adversarial robustness of classification algorithms in machine learning is a crucial domain.However,current methods lack measurable and interpretable metrics.To address this issue,this paper introduces a visual evaluation index named confidence centroid skewing quadrilateral,which is based on a classification confidence-based confusion matrix,offering a quantitative and visual comparison of the adversarial robustness among different classification algorithms,and enhances intuitiveness and interpretability of attack impacts.We first conduct a validity test and sensitive analysis of the method.Then,prove its effectiveness through the experiments of five classification algorithms including artificial neural network(ANN),logistic regression(LR),support vector machine(SVM),convolutional neural network(CNN)and transformer against three adversarial attacks such as fast gradient sign method(FGSM),DeepFool,and projected gradient descent(PGD)attack. 展开更多
关键词 adversarial robustness evaluation visual evaluation classification confidence-based confusion matrix centroid SKEWING
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Robustness Optimization Algorithm with Multi-Granularity Integration for Scale-Free Networks Against Malicious Attacks 被引量:1
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作者 ZHANG Yiheng LI Jinhai 《昆明理工大学学报(自然科学版)》 北大核心 2025年第1期54-71,共18页
Complex network models are frequently employed for simulating and studyingdiverse real-world complex systems.Among these models,scale-free networks typically exhibit greater fragility to malicious attacks.Consequently... Complex network models are frequently employed for simulating and studyingdiverse real-world complex systems.Among these models,scale-free networks typically exhibit greater fragility to malicious attacks.Consequently,enhancing the robustness of scale-free networks has become a pressing issue.To address this problem,this paper proposes a Multi-Granularity Integration Algorithm(MGIA),which aims to improve the robustness of scale-free networks while keeping the initial degree of each node unchanged,ensuring network connectivity and avoiding the generation of multiple edges.The algorithm generates a multi-granularity structure from the initial network to be optimized,then uses different optimization strategies to optimize the networks at various granular layers in this structure,and finally realizes the information exchange between different granular layers,thereby further enhancing the optimization effect.We propose new network refresh,crossover,and mutation operators to ensure that the optimized network satisfies the given constraints.Meanwhile,we propose new network similarity and network dissimilarity evaluation metrics to improve the effectiveness of the optimization operators in the algorithm.In the experiments,the MGIA enhances the robustness of the scale-free network by 67.6%.This improvement is approximately 17.2%higher than the optimization effects achieved by eight currently existing complex network robustness optimization algorithms. 展开更多
关键词 complex network model MULTI-GRANULARITY scale-free networks robustness algorithm integration
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A robustness assessment approach for transportation networks with cyber-physical interdependencies
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作者 Konstantinos Ntafloukas Liliana Pasquale +1 位作者 Beatriz Martinez-Pastor Daniel P.McCrum 《Resilient Cities and Structures》 2025年第1期71-82,共12页
While in the past the robustness of transportation networks was studied considering the cyber and physical space as isolated environments this is no longer the case.Integrating the Internet of Things devices in the se... While in the past the robustness of transportation networks was studied considering the cyber and physical space as isolated environments this is no longer the case.Integrating the Internet of Things devices in the sensing area of transportation infrastructure has resulted in ubiquitous cyber-physical systems and increasing interdependen-cies between the physical and cyber networks.As a result,the robustness of transportation networks relies on the uninterrupted serviceability of physical and cyber networks.Current studies on interdependent networks overlook the civil engineering aspect of cyber-physical systems.Firstly,they rely on the assumption of a uniform and strong level of interdependency.That is,once a node within a network fails its counterpart fails immedi-ately.Current studies overlook the impact of earthquake and other natural hazards on the operation of modern transportation infrastructure,that now serve as a cyber-physical system.The last is responsible not only for the physical operation(e.g.,flow of vehicles)but also for the continuous data transmission and subsequently the cy-ber operation of the entire transportation network.Therefore,the robustness of modern transportation networks should be modelled from a new cyber-physical perspective that includes civil engineering aspects.In this paper,we propose a new robustness assessment approach for modern transportation networks and their underlying in-terdependent physical and cyber network,subjected to earthquake events.The novelty relies on the modelling of interdependent networks,in the form of a graph,based on their interdependency levels.We associate the service-ability level of the coupled physical and cyber network with the damage states induced by earthquake events.Robustness is then measured as a degradation of the cyber-physical serviceability level.The application of the approach is demonstrated by studying an illustrative transportation network using seismic data from real-world transportation infrastructure.Furthermore,we propose the integration of a robustness improvement indicator based on physical and cyber attributes to enhance the cyber-physical serviceability level.Results indicate an improvement in robustness level(i.e.,41%)by adopting the proposed robustness improvement indicator.The usefulness of our approach is highlighted by comparing it with other methods that consider strong interdepen-dencies and key node protection strategies.The approach is of interest to stakeholders who are attempting to incorporate cyber-physical systems into civil engineering systems. 展开更多
关键词 Transportation network Cyber-physical robustness Interdependencies Natural hazards robustness improvement indicator
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A Robustness Evaluation Method for the Robust Control of Electrical Drive Systems based on Six-sigma Methodology
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作者 Nabil Farah Gang Lei +1 位作者 Jianguo Zhu Youguang Guo 《CES Transactions on Electrical Machines and Systems》 2025年第2期131-145,共15页
Numerous uncertainties in practical production and operation can seriously affect the drive performance of permanent magnet synchronous machines(PMSMs).Various robust control methods have been developed to mitigate or... Numerous uncertainties in practical production and operation can seriously affect the drive performance of permanent magnet synchronous machines(PMSMs).Various robust control methods have been developed to mitigate or eliminate the effects of these uncertainties.However,the robustness to uncertainties of electrical drive systems has not been clearly defined.No systemic procedures have been proposed to evaluate a control system's robustness(how robust it is).This paper proposes a systemic method for evaluating control systems'robustness to uncertainties.The concept and fundamental theory of robust control are illustrated by considering a simple uncertain feedback control system.The effects of uncertainties on the control performance and stability are analyzed and discussed.The concept of design for six-sigma(a robust design method)is employed to numerically evaluate the robustness levels of control systems.To show the effectiveness of the proposed robustness evaluation method,case studies are conducted for second-order systems,DC motor drive systems,and PMSM drive systems.Besides the conventional predictive control of PMSM drive,three different robust predictive control methods are evaluated in terms of two different parametric uncertainty ranges and three application requirements against parametric uncertainties. 展开更多
关键词 Permanent magnet synchronous machines(PMSMs) Predictive control UNCERTAINTIES robustness evaluation Robust control Six-sigma
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Structural Features and Robustness of Coupled Software Networks
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作者 WANG Ershen TONG Zeqi +4 位作者 HONG Chen WANG Yanwen MEI Sen XU Song NA La 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第6期801-812,共12页
Software systems play increasing important roles in modern society,and the ability against attacks is of great practical importance to crucial software systems,resulting in that the structure and robustness of softwar... Software systems play increasing important roles in modern society,and the ability against attacks is of great practical importance to crucial software systems,resulting in that the structure and robustness of software systems have attracted a tremendous amount of interest in recent years.In this paper,based on the source code of Tar and MySQL,we propose an approach to generate coupled software networks and construct three kinds of directed software networks:The function call network,the weakly coupled network and the strongly coupled network.The structural properties of these complex networks are extensively investigated.It is found that the average influence and the average dependence for all functions are the same.Moreover,eight attacking strategies and two robustness indicators(the weakly connected indicator and the strongly connected indicator)are introduced to analyze the robustness of software networks.This shows that the strongly coupled network is just a weakly connected network rather than a strongly connected one.For MySQL,high in-degree strategy outperforms other attacking strategies when the weakly connected indicator is used.On the other hand,high out-degree strategy is a good choice when the strongly connected indicator is adopted.This work will highlight a better understanding of the structure and robustness of software networks. 展开更多
关键词 software network software structure software robustness software system complex network
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Laser-based fabrication of superhydrophobic glass with high transparency and robustness
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作者 LIU Chao WANG Qing-hua +4 位作者 GE Zhi-qiang LI Hao-yu FU Jia-jun WANG Hui-xin ZHANG Tai-rui 《Journal of Central South University》 2025年第1期160-173,共14页
Superhydrophobic glass has inspiring development prospects in endoscopes,solar panels and other engineering and medical fields.However,the surface topography required to achieve superhydrophobicity will inevitably aff... Superhydrophobic glass has inspiring development prospects in endoscopes,solar panels and other engineering and medical fields.However,the surface topography required to achieve superhydrophobicity will inevitably affect the surface transparency and limit the application of glass materials.To resolve the contradiction between the surface transparency and the robust superhydrophobicity,an efficient and low-cost laser-chemical surface functionalization process was utilized to fabricate superhydrophobic glass surface.The results show that the air can be effectively trapped in surface micro/nanostructure induced by laser texturing,thus reducing the solid-liquid contact area and interfacial tension.The deposition of hydrophobic carbon-containing groups on the surface can be accelerated by chemical treatment,and the surface energy is significantly reduced.The glass surface exhibits marvelous robust superhydrophobicity with a contact angle of 155.8°and a roll-off angle of 7.2°under the combination of hierarchical micro/nanostructure and low surface energy.Moreover,the surface transparency of the prepared superhydrophobic glass was only 5.42%lower than that of the untreated surface.This superhydrophobic glass with high transparency still maintains excellent superhydrophobicity after durability and stability tests.The facile fabrication of superhydrophobic glass with high transparency and robustness provides a strong reference for further expanding the application value of glass materials. 展开更多
关键词 superhydrophobic glass laser-chemical functionalization TRANSPARENCY robustness highly efficient
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Improving Robustness for Tag Recommendation via Self-Paced Adversarial Metric Learning
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作者 Zhengshun Fei Jianxin Chen +1 位作者 Gui Chen Xinjian Xiang 《Computers, Materials & Continua》 2025年第3期4237-4261,共25页
Tag recommendation systems can significantly improve the accuracy of information retrieval by recommending relevant tag sets that align with user preferences and resource characteristics.However,metric learning method... Tag recommendation systems can significantly improve the accuracy of information retrieval by recommending relevant tag sets that align with user preferences and resource characteristics.However,metric learning methods often suffer from high sensitivity,leading to unstable recommendation results when facing adversarial samples generated through malicious user behavior.Adversarial training is considered to be an effective method for improving the robustness of tag recommendation systems and addressing adversarial samples.However,it still faces the challenge of overfitting.Although curriculum learning-based adversarial training somewhat mitigates this issue,challenges still exist,such as the lack of a quantitative standard for attack intensity and catastrophic forgetting.To address these challenges,we propose a Self-Paced Adversarial Metric Learning(SPAML)method.First,we employ a metric learning model to capture the deep distance relationships between normal samples.Then,we incorporate a self-paced adversarial training model,which dynamically adjusts the weights of adversarial samples,allowing the model to progressively learn from simpler to more complex adversarial samples.Finally,we jointly optimize the metric learning loss and self-paced adversarial training loss in an adversarial manner,enhancing the robustness and performance of tag recommendation tasks.Extensive experiments on the MovieLens and LastFm datasets demonstrate that SPAML achieves F1@3 and NDCG@3 scores of 22%and 32.7%on the MovieLens dataset,and 19.4%and 29%on the LastFm dataset,respectively,outperforming the most competitive baselines.Specifically,F1@3 improves by 4.7%and 6.8%,and NDCG@3 improves by 5.0%and 6.9%,respectively. 展开更多
关键词 Tag recommendation metric learning adversarial training self-paced adversarial training robustness
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Stabilized adaptive waveform inversion for enhanced robustness in Gaussian penalty matrix parameterization and transcranial ultrasound imaging
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作者 Jun-Jie Zhao Shan-Mu Jin +2 位作者 Yue-Kun Wang Yu Wang Ya-Hui Peng 《Chinese Physics B》 2025年第8期606-621,共16页
Achieving high-resolution intracranial imaging in a safe and portable manner is critical for the diagnosis of intracranial diseases,preoperative planning of craniotomies and intraoperative management during craniotomy... Achieving high-resolution intracranial imaging in a safe and portable manner is critical for the diagnosis of intracranial diseases,preoperative planning of craniotomies and intraoperative management during craniotomy procedures.Adaptive waveform inversion(AWI),a variant of full waveform inversion(FWI),has shown potential in intracranial ultrasound imaging.However,the robustness of AWI is affected by the parameterization of the Gaussian penalty matrix and the challenges posed by transcranial scenarios.Conventional AWI struggles to produce accurate images in these cases,limiting its application in critical medical settings.To address these issues,we propose a stabilized adaptive waveform inversion(SAWI)method,which introduces a user-defined zero-lag position for theWiener filter.Numerical experiments demonstrate that SAWI can achieve accurate imaging under Gaussian penalty matrix parameter settings where AWI fails,perform successful transcranial imaging in configurations where AWI cannot,and maintain the same imaging accuracy as AWI.The advantage of this method is that it achieves these advancements without modifying the AWI framework or increasing computational costs,which helps to promote the application of AWI in medical fields,particularly in transcranial scenarios. 展开更多
关键词 ultrasound brain imaging full waveform inversion robustness PARAMETERIZATION
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Robustness and Performance Comparison of Generative AI Time Series Anomaly Detection under Noise
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作者 Jeongsu Park Moohong Min 《Computer Modeling in Engineering & Sciences》 2025年第12期3913-3948,共36页
Time series anomaly detection is critical in domains such as manufacturing,finance,and cybersecurity.Recent generative AI models,particularly Transformer-and Autoencoder-based architectures,show strong accuracy but th... Time series anomaly detection is critical in domains such as manufacturing,finance,and cybersecurity.Recent generative AI models,particularly Transformer-and Autoencoder-based architectures,show strong accuracy but their robustness under noisy conditions is less understood.This study evaluates three representative models—AnomalyTransformer,TranAD,and USAD—on the Server Machine Dataset(SMD)and cross-domain benchmarks including the SoilMoisture Active Passive(SMAP)dataset,theMars Science Laboratory(MSL)dataset,and the Secure Water Treatment(SWaT)testbed.Seven noise settings(five canonical,two mixed)at multiple intensities are tested under fixed clean-data training,with variations in window,stride,and thresholding.Results reveal distinct robustness profiles:AnomalyTransformermaintains recall but loses precision under abrupt noise,TranAD balances sensitivity yet is vulnerable to structured anomalies,and USAD resists Gaussian perturbations but collapses under block anomalies.Quantitatively,F1 drops 60%–70%on noisy SMD,with severe collapse in SWaT(F1≤0.10,Drop up to 84%)but relative stability on SMAP/MSL(Drop within±10%).Overall,generative models exhibit complementary robustness patterns,highlighting noise-type dependent vulnerabilities and providing practical guidance for robust deployment. 展开更多
关键词 Time series anomaly detection robustness evaluation generative AI models AnomalyTransformer TranAD USAD noise injection cross-domain datasets(SMD SMAP MSL SWaT)
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刚柔复合驱动并联式拣矸机器人动力学与鲁棒模型预测控制
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作者 刘鹏 王毅 +4 位作者 马宏伟 段学超 曹现刚 夏晶 聂珍 《煤炭科学技术》 北大核心 2026年第3期320-334,共15页
矸石分拣可以提升煤炭品质、降低运输成本、减少环境污染,实现煤炭资源的高效清洁利用与矿山可持续发展。传统煤矸石人工分拣存在劳动强度大、效率低的问题,提出刚柔复合驱动并联式拣矸机器人构型方案。但是由于拣矸置矸过程所导致的动... 矸石分拣可以提升煤炭品质、降低运输成本、减少环境污染,实现煤炭资源的高效清洁利用与矿山可持续发展。传统煤矸石人工分拣存在劳动强度大、效率低的问题,提出刚柔复合驱动并联式拣矸机器人构型方案。但是由于拣矸置矸过程所导致的动态冲击和动力学参数的不确定,以及外界干扰等因素,势必会影响拣矸机器人末端抓斗的跟踪精度和稳定性,甚至导致拣矸任务无法完成。鉴于此,开展了刚柔复合驱动并联式拣矸机器人动力学与鲁棒模型预测控制研究。首先,提出了刚柔复合驱动并联式拣矸机器人系统方案,分析了机器人末端抓斗的自由度,并采用矢量封闭原理建立了拣矸机器人的运动学模型。其次,考虑机器人模型参数摄动和拣矸置矸过程的外部扰动,基于牛顿-欧拉方程建立了刚柔复合驱动并联式拣矸机器人的动力学模型。再次,提出了融合张力约束的鲁棒模型预测控制方法,实时优化柔索-推杆驱动力协同分配,动态抵消矸石抓取与置放过程的冲击与外部扰动,实现拣矸机器人末端抓斗高精度轨迹跟踪控制。最后,采用空间螺旋轨迹和4段式分拣轨迹(启动段—准备段—抓矸段—置矸段)对刚柔复合驱动并联式拣矸机器人鲁棒模型预测控制系统进行了仿真分析,结果表明:末端抓斗轨迹最大偏移量仅3.7×10^(-3) m,姿态角误差稳定于3.2×10^(-3) rad,且柔索张力始终满足驱动力约束条件,验证了控制策略对复杂工况下拣矸作业的有效性。 展开更多
关键词 刚柔复合驱动 并联机器人 矸石分拣 鲁棒模型预测控制 鲁棒性
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一种改进抗差自适应滤波的UWB定位方法 被引量:1
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作者 郭英 周振平 +2 位作者 崔健慧 谢永强 苏辕 《武汉大学学报(信息科学版)》 北大核心 2026年第1期182-190,共9页
针对超宽带(ultra-wide band,UWB)定位时存在的非视距(non-line-of-sight,NLOS)误识别、漏识别等问题,提出一种基于滑动窗口方差检测与新息检测的抗差自适应滤波算法。在新息抗差自适应算法的基础上,利用滑动窗口方差检测结合新息检测... 针对超宽带(ultra-wide band,UWB)定位时存在的非视距(non-line-of-sight,NLOS)误识别、漏识别等问题,提出一种基于滑动窗口方差检测与新息检测的抗差自适应滤波算法。在新息抗差自适应算法的基础上,利用滑动窗口方差检测结合新息检测的方式,降低模型扰动状态下的NLOS误识别与漏识别率;同时,利用距离平滑与距离更新对方差检测方法进行优化,解决了方差检测的检测退化问题。实验结果表明,在视距环境下,所提算法定位精度高,为0.073 m;在人员遮挡环境下,定位精度为0.077 m,相较于最小二乘、卡尔曼滤波、新息抗差自适应滤波算法,精度分别提升了40.3%、33.6%、28.7%;在立柱遮挡及地下车库等较严重NLOS环境下,所提算法定位精度为0.125 m,相较于最小二乘、卡尔曼滤波、新息抗差自适应滤波算法,车库环境定位精度分别提升了80.8%、73.7%、36.2%。而且在3种NLOS环境下,相较于新息抗差自适应滤波算法,NLOS误识别率降低了38.2%以上,能够满足室内复杂环境下的高精度定位需求。 展开更多
关键词 UWB定位 扩展卡尔曼滤波 鲁棒自适应滤波 NLOS误差
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计及灵活性供需平衡的源荷储资源数据驱动鲁棒优化调度
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作者 黄震 侯凯元 +3 位作者 张健男 夏德明 鞠立伟 潘昱树 《电网技术》 北大核心 2026年第4期1498-1507,I0033-I0038,共16页
新型电力系统建设背景下,新能源渗透率不断提高造成电力系统灵活性需求剧增。针对电力系统灵活性供需失衡问题,提出含碳捕集电厂的源荷储资源数据驱动鲁棒优化调度模型。首先,基于碳捕集电厂、抽水蓄能等源荷储灵活性资源运行特性,刻画... 新型电力系统建设背景下,新能源渗透率不断提高造成电力系统灵活性需求剧增。针对电力系统灵活性供需失衡问题,提出含碳捕集电厂的源荷储资源数据驱动鲁棒优化调度模型。首先,基于碳捕集电厂、抽水蓄能等源荷储灵活性资源运行特性,刻画电力系统灵活性供给能力;其次,采用数据驱动方法构建椭球不确定性集以刻画风电、光伏波动区间,根据各时刻边界值量化灵活性需求;进而,结合灵活性供需关系,提出源荷储资源数据驱动鲁棒优化模型,并采用改进列与约束生成算法(column and constraint generation,C&CG)进行求解。算例仿真表明,通过协同调度源荷储灵活性资源有助于支撑电力系统功率平衡,提高灵活性裕度,数据驱动鲁棒优化方法能够剔除传统盒式不确定集中的不实际恶劣场景,进而改善传统鲁棒优化模型过于保守的问题,并显著提升计算效率。 展开更多
关键词 源荷储资源 灵活性供需平衡 数据驱动 鲁棒优化
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基于新型趋近律的表贴式永磁同步电机抗扰滑模控制策略
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作者 王要强 陈晨 +3 位作者 张世达 聂福全 张晓光 梁军 《电力系统保护与控制》 北大核心 2026年第2期151-161,共11页
针对表贴式永磁同步电机(permanent magnet synchronous motor,PMSM)转速环存在的负载扰动、参数失配等不确定性问题,提出一种基于新型趋近律的抗扰滑模控制策略。首先,提出一种新型自适应趋近律,所提趋近律在等速项中引入系统滑模变量... 针对表贴式永磁同步电机(permanent magnet synchronous motor,PMSM)转速环存在的负载扰动、参数失配等不确定性问题,提出一种基于新型趋近律的抗扰滑模控制策略。首先,提出一种新型自适应趋近律,所提趋近律在等速项中引入系统滑模变量的自适应增益,解决了传统指数趋近律收敛速度与滑模抖振的矛盾问题,减小了跟踪误差,且避免了趋近速度突变问题。然后,基于所提新型趋近律和非奇异积分终端滑模面设计了转速环滑模控制器。最后,为进一步提高系统的抗扰性能,设计扩展滑模扰动观测器观测并补偿转速环的不确定性扰动。仿真与实验结果表明,所提抗扰滑模控制策略能有效提高电机调速系统的动态性能和鲁棒性。 展开更多
关键词 永磁同步电机 滑模控制 新型趋近律 动态性能 鲁棒性
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基于逐帧迭代幂次法鲁棒远场语音识别
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作者 尚莹莹 马永强 《计算机应用与软件》 北大核心 2026年第2期231-241,共11页
为实现实时远场语音识别,提出一种基于逐帧迭代幂次法的鲁棒远场语音识别方法。在最大似然无失真响应波束形成框架中通过迭代更新规则获得观测噪声语音信号的方差加权空间协方差矩阵估计。逐帧将转向矢量估计和波束形成进行迭代计算,同... 为实现实时远场语音识别,提出一种基于逐帧迭代幂次法的鲁棒远场语音识别方法。在最大似然无失真响应波束形成框架中通过迭代更新规则获得观测噪声语音信号的方差加权空间协方差矩阵估计。逐帧将转向矢量估计和波束形成进行迭代计算,同时用于波束形成和去混响,并且引入幂次法实现在线处理。经过训练的神经网络能够改进具有时变方差的零均值高斯分布。通过多个数据集实验证明了该方法的有效性。 展开更多
关键词 远场语音识别 幂次法 鲁棒性 协方差矩阵
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最优模糊理论的下肢机器人自适应鲁棒控制
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作者 陈元富 贺元成 《机械设计与制造》 北大核心 2026年第2期298-308,共11页
为了解决不确定性和外部干扰,提出了一种基于最优模糊理论的下肢外骨骼机器人自适应鲁棒控制方法。首先提出一种自适应鲁棒控制,保证系统的一致有界性和一致最终有界性。然后采用模糊集理论来描述不确定性和干扰,并用隶属函数确定这些... 为了解决不确定性和外部干扰,提出了一种基于最优模糊理论的下肢外骨骼机器人自适应鲁棒控制方法。首先提出一种自适应鲁棒控制,保证系统的一致有界性和一致最终有界性。然后采用模糊集理论来描述不确定性和干扰,并用隶属函数确定这些不确定性和干扰的界。在此基础上,构造一个包含平均模糊系统性能和控制代价的模糊性能指标,求出自适应鲁棒控制的最优控制增益,并从理论上验证了最优控制增益的存在性。最后,通过仿真结果证明了提出方法可以同时实现高精度跟踪控制和良好的不确定性鲁棒控制。 展开更多
关键词 不确定性 下肢外骨骼机器人 鲁棒控制 模糊集理论
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压电作动器的多目标互补鲁棒控制方法研究
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作者 陈辉 齐苗苗 +2 位作者 刘佳彬 连峰 韩崇昭 《控制理论与应用》 北大核心 2026年第2期227-238,共12页
针对存在模型不确定性、外界干扰和测量噪声下的压电作动器(PEA)高精度跟踪控制问题,本文提出多目标互补鲁棒控制方法.首先,建立基于Hammerstein模型结构的率相关迟滞非线性模型,其中系统的静态迟滞非线性环节采用Prandtl-Ishlinskii(PI... 针对存在模型不确定性、外界干扰和测量噪声下的压电作动器(PEA)高精度跟踪控制问题,本文提出多目标互补鲁棒控制方法.首先,建立基于Hammerstein模型结构的率相关迟滞非线性模型,其中系统的静态迟滞非线性环节采用Prandtl-Ishlinskii(PI)模型描述,动态线性环节则由改进的相关性辨识法得到.然后,在此模型基础上,提出用多目标互补鲁棒控制方法来实现压电作动器的高精度跟踪控制,该控制器应用PID控制理念实现闭环系统的最优性能,并采用鲁棒控制策略达到闭环系统的鲁棒稳定,同时融合了Youla参数化的思想解决系统最优性能与鲁棒性之间的矛盾.最后,通过实验验证系统的跟踪精度及抗干扰能力,证明了本文所提出方法的有效性. 展开更多
关键词 压电作动器 鲁棒控制 相关性辨识 YOULA参数化 卡尔曼滤波 多目标互补控制
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求解时变线性方程的噪声抑制零化神经网络
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作者 李春泉 严达萱 +4 位作者 李定钰 单思淇 汪芊芊 赖青梧 李志农 《振动.测试与诊断》 北大核心 2026年第1期1-9,212,共10页
时变线性方程的快速求解在工程计算和机器人控制中具有重要意义,但现有零化神经网络通常面临收敛速度慢和对噪声敏感的问题。对此,提出了一种具有噪声抑制能力的预定义时间收敛的零化神经网络(predefined-time convergent noise-suppres... 时变线性方程的快速求解在工程计算和机器人控制中具有重要意义,但现有零化神经网络通常面临收敛速度慢和对噪声敏感的问题。对此,提出了一种具有噪声抑制能力的预定义时间收敛的零化神经网络(predefined-time convergent noise-suppressing zeroing neural network,简称PTC-NS-ZNN)模型。首先,设计了一种基于模糊逻辑的参数调节机制,使激活函数可随误差变化自适应调整非线性增益,从而增强系统的瞬态性能并提高稳态精度;其次,从理论上分析了所提模型的稳定性、预定义时间收敛性及抗噪性能,证明了其在给定时间上界内可实现全局收敛,并具备有界噪声抑制能力;然后,在无噪声及多种经典噪声干扰环境下进行了数值仿真对比实验,发现相较于现有模型,PTC-NS-ZNN模型具有更快的收敛速度和更强的抗干扰能力;最后,将所提出模型应用于双机械臂轨迹规划,实验结果验证了其在不同环境下的高精度与实用性。研究结果表明,PTC-NS-ZNN模型在数值仿真和物理实验中均展现出显著优势,具有良好的工程应用潜力。 展开更多
关键词 零化神经网络 时变线性方程 预定义时间收敛 鲁棒性
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带时间趋势面板数据模型的众数回归估计
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作者 程瑶 韩忠成 +1 位作者 闫舒婷 林金官 《统计与信息论坛》 北大核心 2026年第3期1-11,共11页
目前,关于面板数据的研究大多数是基于最小二乘损失和分位数损失展开的,但当数据分布出现严重偏态时,基于以上损失的面板数据模型缺乏稳健性和有效性。一种常见的方法是在面板模型中引入众数损失函数,通过调节参数获得稳健性和有效性。... 目前,关于面板数据的研究大多数是基于最小二乘损失和分位数损失展开的,但当数据分布出现严重偏态时,基于以上损失的面板数据模型缺乏稳健性和有效性。一种常见的方法是在面板模型中引入众数损失函数,通过调节参数获得稳健性和有效性。然而,传统固定效应众数回归模型未考虑时点效应,而时点效应能够刻画被解释变量的时间变化趋势,忽略该效应意味着部分时变规律未被反映。为克服这一局限,将众数回归思想引入固定效应模型,并在模型结构中加入时间趋势项,形成带趋势的固定效应面板数据众数回归模型,从而实现个体异质性与时间变化特征的同步刻画。首先,采用B样条基函数对模型中趋势项进行拟合,然后结合MEM算法通过最大化众数回归目标函数得到众数回归的估计。其次,在一定的正则条件下,给出估计量的渐近分布和大样本性质。蒙特卡罗模拟显示,该模型在偏态分布条件下具有较高估计精度和抗干扰能力。最后,基于中国2012—2021年的省级面板数据,实证分析外商直接投资对区域经济增长的影响。根据R2与BIC指标的比较结果,带趋势项的固定效应众数回归模型在拟合效果和稳健性方面均优于传统方法,能够更充分揭示经济变量的时间动态特征。研究结果表明,该模型拓展了众数回归的理论体系,并为含时间趋势的经济面板数据分析提供了稳健而有效的工具。 展开更多
关键词 B样条 众数回归 稳健估计 时间趋势 固定效应模型
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基于观测状态修正的微电网储能双向DC-DC变换器自抗扰稳压策略
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作者 周雪松 景亚楠 +3 位作者 马幼捷 王鑫 陶珑 问虎龙 《电力自动化设备》 北大核心 2026年第1期185-193,共9页
在直流微电网中,高比例光伏设备的出力波动需要储能单元进行补偿和调节,但在复杂工况下,储能端口双向DC-DC变换器的稳压性能往往不能得到有效保障。为此,以直流微电网中的储能双向DC-DC变换器为研究对象,提出一种考虑观测偏差高阶修正... 在直流微电网中,高比例光伏设备的出力波动需要储能单元进行补偿和调节,但在复杂工况下,储能端口双向DC-DC变换器的稳压性能往往不能得到有效保障。为此,以直流微电网中的储能双向DC-DC变换器为研究对象,提出一种考虑观测偏差高阶修正的自抗扰稳压策略。将传统自抗扰控制中被忽略的偏差项定义为扰动观测高阶分量,并将其补偿到观测器结构中得到精确的修正变量,实现自抗扰观测偏差的精准和快速收敛;从时域、频域维度分析该策略能够有效改善观测性、抗扰性、鲁棒性的原因,并利用李雅普诺夫理论证明所提控制策略的稳定性。仿真结果表明,所提策略控制下的储能双向DC-DC变换器在多种复杂场景中均表现出较好的抗扰性和鲁棒性。 展开更多
关键词 微电网 自抗扰控制 变换器 状态修正 抗扰性能 鲁棒性能
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