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面向无人机路径规划的改进Theta^(*)算法
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作者 马超 赵佳宝 孙纬 《制造业自动化》 2025年第5期18-25,共8页
为了优化无人机在未知三维环境中的路径规划,并解决传统Theta^(*)算法在寻优搜索时耗时较长的问题,提出了一种改进的Theta^(*)算法。通过模拟无人机飞行时的真实场景,构造了不同密度障碍的城市环境模型;然后综合考虑实际飞行的避障要求... 为了优化无人机在未知三维环境中的路径规划,并解决传统Theta^(*)算法在寻优搜索时耗时较长的问题,提出了一种改进的Theta^(*)算法。通过模拟无人机飞行时的真实场景,构造了不同密度障碍的城市环境模型;然后综合考虑实际飞行的避障要求与生成路径的平滑程度,改进了传统的代价函数;采用分层规划器划分三维空间,降低了算法在未知飞行环境下的搜索时间;最后使用局部优化方法,优化关键节点的平滑度,使无人机在复杂的环境当中保持飞行的连续。在进行无人机路径规划时,改进后的算法相比于传统的Theta^(*)算法,复杂障碍物环境下路径寻优的效率和精度有了明显改善。 展开更多
关键词 路径规划 无人机 theta^(*)算法 分层规划器 局部优化
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基于Basic Theta^(*)算法的声发射源定位方法 被引量:2
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作者 张力中 任会兰 李涛 《兵工学报》 北大核心 2025年第2期165-177,共13页
对于大型混凝土、岩石等结构,由于其内部含有空区结构,弹性波会绕过空区沿非直线路径传播,基于直线路径的传统时差定位算法误差较大。为提高含空区结构中的声发射源定位精度,基于Basic Theta^(*)算法提出一种适用于含空区结构的声发射... 对于大型混凝土、岩石等结构,由于其内部含有空区结构,弹性波会绕过空区沿非直线路径传播,基于直线路径的传统时差定位算法误差较大。为提高含空区结构中的声发射源定位精度,基于Basic Theta^(*)算法提出一种适用于含空区结构的声发射源定位方法,通过含圆形空区混凝土平板表面的断铅试验对该方法进行了验证,并讨论了传感器数量、传感器位置、声发射源位置对声发射源定位误差的影响。采用多通道声发射测试系统获得了混凝土平板中波速随传播距离衰减的规律;单个和多个声发射源的定位结果表明,相较于传统时差定位方法和A^(*)定位方法,提出的定位方法有效降低了弹性波绕过空区传播对定位的影响,大幅度提高了含空区混凝土结构中的声发射源定位精度及效率。 展开更多
关键词 声发射 含空区混凝土 波速衰减 Basic theta^(*)算法
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Theta爆发式经颅磁刺激的文献计量学和可视化分析 被引量:1
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作者 高文艳 郑兆燕 +3 位作者 潘尚 王佩佩 吉春辉 吕少萍 《中国组织工程研究》 CAS 北大核心 2025年第20期4389-4400,共12页
背景:相比于常规重复经颅磁刺激,Theta爆发式经颅磁刺激因具有刺激时间短、效率高、安全性好和效果持久等优势,正受到各领域学者的广泛关注,研究热度持续上升。目的:通过对近20年国际Theta爆发式经颅磁刺激研究进行文献计量学的可视化分... 背景:相比于常规重复经颅磁刺激,Theta爆发式经颅磁刺激因具有刺激时间短、效率高、安全性好和效果持久等优势,正受到各领域学者的广泛关注,研究热度持续上升。目的:通过对近20年国际Theta爆发式经颅磁刺激研究进行文献计量学的可视化分析,梳理Theta爆发式经颅磁刺激研究的发展脉络,总结研究现状,揭示研究热点和发展趋势,为后续研究提供借鉴和参考。方法:检索Web of Science核心集数据库中2005年1月至2024年6月有关Theta爆发式经颅磁刺激的相关文献,应用CiteSpace软件进行年度发文量分析,国家、机构和作者合作共现分析,参考文献、期刊和作者共被引分析,关键词共现、聚类、时间演化和突现分析等,并绘制可视化知识图谱。结果与结论:①共纳入1914篇文献,近20年Theta爆发式经颅磁刺激研究量呈总体上升趋势,预计未来将继续保持研究热度。②发文量前3位的国家为美国、中国和意大利,机构为加拿大多伦多大学、英国伦敦大学和美国哈佛大学医学院;美国哈佛大学医学院的Pascual-leone,Alvaro研究成果最多,中国长庚大学的HUANG YZ被引频次最高;《NEURON》为影响力最大的期刊。③高频关键词、高被引文献和聚类主题结果显示,近20年Theta爆发式经颅磁刺激研究热点主要集中于:Theta爆发式经颅磁刺激对突触可塑性和神经生理活动的作用机制,Theta爆发式经颅磁刺激刺激不同脑区靶点的作用效果(包括运动皮质、背外侧前额叶皮质、前扣带皮质和小脑等),以及Theta爆发式经颅磁刺激对神经和精神疾病的疗效探讨(包括抑郁症、帕金森病运动障碍、脑卒中后运动障碍和认知障碍,以及阿尔茨海默病记忆障碍等)。此外,综述和临床试验类文献被引频次最高,未来可重点关注。④关键词突现、文献突现和关键词时间演化分析显示,“重度抑郁症、应用指南、评定量表、疗效、障碍、难治性抑郁症、Meta分析”等不仅是当前的研究热点,也是未来的研究趋势。⑤未来,Theta爆发式经颅磁刺激研究应加强核心作者和机构的区域性合作,发掘其在临床难治性疾病中的应用,通过结合前沿技术和优化刺激参数,实现Theta爆发式经颅磁刺激应用的精准化、个性化和最优化,解决更多临床难题。 展开更多
关键词 theta爆发式经颅磁刺激 文献计量学 CiteSpace 可视化分析 可塑性 长时程增强 长时程抑制
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基于Theta^(*)算法和启发路径的无人艇全局路径规划
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作者 杜家辉 李恒宇 +2 位作者 瞿栋 鲍凌志 钟雨轩 《中国测试》 北大核心 2025年第5期101-109,共9页
在无人艇全局路径规划中,许多算法仅考虑效率而忽略航行安全性。为满足安全性需求,该文提出一种由启发路径构建风险评估函数,并引导最终规划路径向启发路径靠拢的方法。首先,依据启发路径的周围环境构建风险评估函数;其次,对Theta^(*)... 在无人艇全局路径规划中,许多算法仅考虑效率而忽略航行安全性。为满足安全性需求,该文提出一种由启发路径构建风险评估函数,并引导最终规划路径向启发路径靠拢的方法。首先,依据启发路径的周围环境构建风险评估函数;其次,对Theta^(*)算法进行改良,将路径代价作为父节点选取的指标之一;最后,提出一种非均匀代价的计算方式,并与改良Theta^(*)算法相结合,进而得到一条能够避开危险区域,兼具效率与安全性的全局路径。此外,通过一系列实验表明,该文方法成功绕开危险区域,并可根据具体任务需求调整危险系数大小,以较少的路径长度增加换取路径安全性的大幅提升,在实际环境中能够有效规划一条满足任务需求的全局路径。 展开更多
关键词 无人艇 路径规划 启发路径 改良theta^(*)算法
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硫酸酯酶抑制剂DU-14拮抗β-淀粉样蛋白改善大鼠海马theta节律及抑郁表现
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作者 岳兴华 王昭君 +2 位作者 武美娜 蔡红艳 张军 《生理学报》 北大核心 2025年第5期801-810,共10页
海马体作为边缘系统的重要组成部分参与学习记忆及情绪调节。阿尔茨海默病患者的认知功能减退及抑郁表现可能与β-淀粉样蛋白(amyloidβ-protein,Aβ)对海马的损伤有关。我们既往研究发现硫酸酯酶抑制剂DU-14可以通过拮抗Aβ毒性,改善A... 海马体作为边缘系统的重要组成部分参与学习记忆及情绪调节。阿尔茨海默病患者的认知功能减退及抑郁表现可能与β-淀粉样蛋白(amyloidβ-protein,Aβ)对海马的损伤有关。我们既往研究发现硫酸酯酶抑制剂DU-14可以通过拮抗Aβ毒性,改善AD动物模型海马突触可塑性并提高其空间记忆能力,但对DU-14是否可以改善AD动物模型的抑郁表现尚缺乏实验证据。本研究利用糖水偏好实验、悬尾实验、强迫游泳实验和在体海马局部场电位记录技术,观察了海马注射DU-14对Aβ_(1-42)海马注射诱导AD大鼠模型的抑郁表现及theta节律神经振荡活动的影响。结果显示,与对照组相比,海马注射Aβ_(1-42)寡聚体两周后:(1)大鼠对愉悦活动的兴趣减弱,在糖水偏好实验中糖水偏好指数降低;(2)大鼠绝望抑郁情绪增加,在悬尾实验及强迫游泳实验中消极不动时间增加;(3)大鼠海马theta节律神经振荡活动减弱,其功率值减低。DU-14+Aβ组大鼠与Aβ组大鼠相比:(1)海马注射DU-14有效缓解了Aβ诱导的大鼠快感缺乏,糖水偏好指数升高;(2)海马注射DU-14有效降低了Aβ诱导的大鼠绝望抑郁表现,悬尾实验及强迫游泳实验中不动时间减少;(3)海马注射DU-14有效阻断了Aβ对大鼠双侧海马theta节律神经振荡活动的压抑。以上结果表明,硫酸酯酶抑制剂DU-14可拮抗Aβ神经毒性,解除其对海马theta节律神经振荡的压抑,并改善AD动物模型的抑郁表现。 展开更多
关键词 Β-淀粉样蛋白 硫酸酯酶抑制剂 抑郁 阿尔茨海默病 theta节律
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Method for Estimating the State of Health of Lithium-ion Batteries Based on Differential Thermal Voltammetry and Sparrow Search Algorithm-Elman Neural Network 被引量:1
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作者 Yu Zhang Daoyu Zhang TiezhouWu 《Energy Engineering》 EI 2025年第1期203-220,共18页
Precisely estimating the state of health(SOH)of lithium-ion batteries is essential for battery management systems(BMS),as it plays a key role in ensuring the safe and reliable operation of battery systems.However,curr... Precisely estimating the state of health(SOH)of lithium-ion batteries is essential for battery management systems(BMS),as it plays a key role in ensuring the safe and reliable operation of battery systems.However,current SOH estimation methods often overlook the valuable temperature information that can effectively characterize battery aging during capacity degradation.Additionally,the Elman neural network,which is commonly employed for SOH estimation,exhibits several drawbacks,including slow training speed,a tendency to become trapped in local minima,and the initialization of weights and thresholds using pseudo-random numbers,leading to unstable model performance.To address these issues,this study addresses the challenge of precise and effective SOH detection by proposing a method for estimating the SOH of lithium-ion batteries based on differential thermal voltammetry(DTV)and an SSA-Elman neural network.Firstly,two health features(HFs)considering temperature factors and battery voltage are extracted fromthe differential thermal voltammetry curves and incremental capacity curves.Next,the Sparrow Search Algorithm(SSA)is employed to optimize the initial weights and thresholds of the Elman neural network,forming the SSA-Elman neural network model.To validate the performance,various neural networks,including the proposed SSA-Elman network,are tested using the Oxford battery aging dataset.The experimental results demonstrate that the method developed in this study achieves superior accuracy and robustness,with a mean absolute error(MAE)of less than 0.9%and a rootmean square error(RMSE)below 1.4%. 展开更多
关键词 Lithium-ion battery state of health differential thermal voltammetry Sparrow Search algorithm
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Theta刺激治疗脑卒中患者下肢运动功能和日常活动能力的Meta分析
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作者 胡鑫 万海丽 +2 位作者 杜亮 李永杰 夏渊 《中国组织工程研究》 北大核心 2026年第10期2576-2583,共8页
目的:通过Meta分析系统性评估间歇性Theta刺激改善脑卒中患者下肢运动功能、平衡功能以及日常活动能力的效果。方法:检索Cochrane Library、Scopus、PubMed、Embase、ProQuest、Web of Science、中国知网、中国生物医学、维普和万方数据... 目的:通过Meta分析系统性评估间歇性Theta刺激改善脑卒中患者下肢运动功能、平衡功能以及日常活动能力的效果。方法:检索Cochrane Library、Scopus、PubMed、Embase、ProQuest、Web of Science、中国知网、中国生物医学、维普和万方数据库,选择各数据库建库至2024年11月期间间歇性Theta刺激治疗脑卒中的随机对照试验。其中,试验组接受小脑/M1区间歇性Theta刺激,对照组进行常规康复治疗。采用RevMan 5.3和Stata 16.0进行Meta分析。结果:共纳入12篇文献,444例患者。Meta分析表明,间歇性Theta刺激有助于提高脑卒中患者下肢Fugl-Meyer量表评分[WMD=2.87,95%CI(1.77,3.98),P<0.00001]、Berg平衡量表评分[WMD=5.79,95%CI(3.80,7.79),P<0.00001]以及改良Barthel指数[WMD=6.32,95%CI(4.02,8.44),P<0.00001]。亚组分析结果显示,相较于600脉冲刺激,1200脉冲刺激更有利于改善下肢Fugl-Meyer量表评分[WMD=4.31,95%CI(2.91,5.71),P<0.00001]、Berg平衡量表评分[WMD=8.12,95%CI(5.27,10.98),P<0.00001]和改良Barthel指数[WMD=8.50,95%CI(6.55,10.45),P<0.00001]。结论:间歇性Theta刺激能够提高脑卒中患者的下肢运动能力、平衡功能及日常生活能力评分。其中,1200脉冲间歇性Theta刺激在改善下肢运动能力、平衡功能和日常生活能力方面,可能具有更大益处。 展开更多
关键词 theta 间歇性theta刺激 脑卒中 下肢 META分析 平衡 日常活动能力 运动功能
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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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Short-TermWind Power Forecast Based on STL-IAOA-iTransformer Algorithm:A Case Study in Northwest China 被引量:2
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作者 Zhaowei Yang Bo Yang +5 位作者 Wenqi Liu Miwei Li Jiarong Wang Lin Jiang Yiyan Sang Zhenning Pan 《Energy Engineering》 2025年第2期405-430,共26页
Accurate short-term wind power forecast technique plays a crucial role in maintaining the safety and economic efficiency of smart grids.Although numerous studies have employed various methods to forecast wind power,th... Accurate short-term wind power forecast technique plays a crucial role in maintaining the safety and economic efficiency of smart grids.Although numerous studies have employed various methods to forecast wind power,there remains a research gap in leveraging swarm intelligence algorithms to optimize the hyperparameters of the Transformer model for wind power prediction.To improve the accuracy of short-term wind power forecast,this paper proposes a hybrid short-term wind power forecast approach named STL-IAOA-iTransformer,which is based on seasonal and trend decomposition using LOESS(STL)and iTransformer model optimized by improved arithmetic optimization algorithm(IAOA).First,to fully extract the power data features,STL is used to decompose the original data into components with less redundant information.The extracted components as well as the weather data are then input into iTransformer for short-term wind power forecast.The final predicted short-term wind power curve is obtained by combining the predicted components.To improve the model accuracy,IAOA is employed to optimize the hyperparameters of iTransformer.The proposed approach is validated using real-generation data from different seasons and different power stations inNorthwest China,and ablation experiments have been conducted.Furthermore,to validate the superiority of the proposed approach under different wind characteristics,real power generation data fromsouthwestChina are utilized for experiments.Thecomparative results with the other six state-of-the-art prediction models in experiments show that the proposed model well fits the true value of generation series and achieves high prediction accuracy. 展开更多
关键词 Short-termwind power forecast improved arithmetic optimization algorithm iTransformer algorithm SimuNPS
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A LODBO algorithm for multi-UAV search and rescue path planning in disaster areas 被引量:1
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作者 Liman Yang Xiangyu Zhang +2 位作者 Zhiping Li Lei Li Yan Shi 《Chinese Journal of Aeronautics》 2025年第2期200-213,共14页
In disaster relief operations,multiple UAVs can be used to search for trapped people.In recent years,many researchers have proposed machine le arning-based algorithms,sampling-based algorithms,and heuristic algorithms... In disaster relief operations,multiple UAVs can be used to search for trapped people.In recent years,many researchers have proposed machine le arning-based algorithms,sampling-based algorithms,and heuristic algorithms to solve the problem of multi-UAV path planning.The Dung Beetle Optimization(DBO)algorithm has been widely applied due to its diverse search patterns in the above algorithms.However,the update strategies for the rolling and thieving dung beetles of the DBO algorithm are overly simplistic,potentially leading to an inability to fully explore the search space and a tendency to converge to local optima,thereby not guaranteeing the discovery of the optimal path.To address these issues,we propose an improved DBO algorithm guided by the Landmark Operator(LODBO).Specifically,we first use tent mapping to update the population strategy,which enables the algorithm to generate initial solutions with enhanced diversity within the search space.Second,we expand the search range of the rolling ball dung beetle by using the landmark factor.Finally,by using the adaptive factor that changes with the number of iterations.,we improve the global search ability of the stealing dung beetle,making it more likely to escape from local optima.To verify the effectiveness of the proposed method,extensive simulation experiments are conducted,and the result shows that the LODBO algorithm can obtain the optimal path using the shortest time compared with the Genetic Algorithm(GA),the Gray Wolf Optimizer(GWO),the Whale Optimization Algorithm(WOA)and the original DBO algorithm in the disaster search and rescue task set. 展开更多
关键词 Unmanned aerial vehicle Path planning Meta heuristic algorithm DBO algorithm NP-hard problems
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基于Theta^(*)算法的消防远程供水可视化平台构建
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作者 曾爱军 周俊秋 《中国人民警察大学学报》 2025年第10期73-78,共6页
为了在大规模灭火救援战斗中快速规划路程短、安全性高的远程供水路径,基于Grasshop⁃per(GH)可视化编程环境搭建消防远程供水可视化智能规划平台。该平台根据矢量地图对建筑、水域、道路、铁路等要素的分类,基于Theta^(*)算法进行障碍规... 为了在大规模灭火救援战斗中快速规划路程短、安全性高的远程供水路径,基于Grasshop⁃per(GH)可视化编程环境搭建消防远程供水可视化智能规划平台。该平台根据矢量地图对建筑、水域、道路、铁路等要素的分类,基于Theta^(*)算法进行障碍规避,并在可用于水带敷设的道路上生成最短路径。Theta^(*)算法需要依据网格进行运算,而在灾情处置的实际应用中,网格尺寸严重影响最短路径的生成质量。在网格划分过程中引入Nelder-Mead(NM)最优化算法,以解决精确匹配网格尺寸存在困难的问题,为大规模灭火救援行动的智能化升级提供经验与支持。 展开更多
关键词 消防远程供水 可视化编程环境 theta^(*)算法 Nelder-Mead算法
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Research on Euclidean Algorithm and Reection on Its Teaching
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作者 ZHANG Shaohua 《应用数学》 北大核心 2025年第1期308-310,共3页
In this paper,we prove that Euclid's algorithm,Bezout's equation and Divi-sion algorithm are equivalent to each other.Our result shows that Euclid has preliminarily established the theory of divisibility and t... In this paper,we prove that Euclid's algorithm,Bezout's equation and Divi-sion algorithm are equivalent to each other.Our result shows that Euclid has preliminarily established the theory of divisibility and the greatest common divisor.We further provided several suggestions for teaching. 展开更多
关键词 Euclid's algorithm Division algorithm Bezout's equation
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基于F-theta 透镜与楔镜分束的太赫兹技术研究
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作者 林子豪 李全勇 +1 位作者 任姣姣 薛竣文 《长春理工大学学报(自然科学版)》 2025年第2期45-54,共10页
为了提高太赫兹线扫描成像系统的扫描精度与信息提取的准确性,优化设计了其中的分束系统与扫描系统。设计了不同角度的楔镜将平板分束镜中多次反射所产生的回波信号消除,分析了不同楔角下的信号强度,并将高阻硅楔镜、薄膜分束器与HDPE(... 为了提高太赫兹线扫描成像系统的扫描精度与信息提取的准确性,优化设计了其中的分束系统与扫描系统。设计了不同角度的楔镜将平板分束镜中多次反射所产生的回波信号消除,分析了不同楔角下的信号强度,并将高阻硅楔镜、薄膜分束器与HDPE(高密度聚乙烯)楔镜进行信号强度对比。设计了准直透镜和F-theta透镜组成的扫描系统,通过使用非球面使得F-theta透镜的视场角在±30°内实现等相位,最后给出透镜扫描的实验结果与预期相符合,误差小于1%。 展开更多
关键词 太赫兹时域光谱系统 扫描系统 分束系统 F-theta透镜 楔镜
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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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Bearing capacity prediction of open caissons in two-layered clays using five tree-based machine learning algorithms 被引量:1
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作者 Rungroad Suppakul Kongtawan Sangjinda +3 位作者 Wittaya Jitchaijaroen Natakorn Phuksuksakul Suraparb Keawsawasvong Peem Nuaklong 《Intelligent Geoengineering》 2025年第2期55-65,共11页
Open caissons are widely used in foundation engineering because of their load-bearing efficiency and adaptability in diverse soil conditions.However,accurately predicting their undrained bearing capacity in layered so... Open caissons are widely used in foundation engineering because of their load-bearing efficiency and adaptability in diverse soil conditions.However,accurately predicting their undrained bearing capacity in layered soils remains a complex challenge.This study presents a novel application of five ensemble machine(ML)algorithms-random forest(RF),gradient boosting machine(GBM),extreme gradient boosting(XGBoost),adaptive boosting(AdaBoost),and categorical boosting(CatBoost)-to predict the undrained bearing capacity factor(Nc)of circular open caissons embedded in two-layered clay on the basis of results from finite element limit analysis(FELA).The input dataset consists of 1188 numerical simulations using the Tresca failure criterion,varying in geometrical and soil parameters.The FELA was performed via OptumG2 software with adaptive meshing techniques and verified against existing benchmark studies.The ML models were trained on 70% of the dataset and tested on the remaining 30%.Their performance was evaluated using six statistical metrics:coefficient of determination(R²),mean absolute error(MAE),root mean squared error(RMSE),index of scatter(IOS),RMSE-to-standard deviation ratio(RSR),and variance explained factor(VAF).The results indicate that all the models achieved high accuracy,with R²values exceeding 97.6%and RMSE values below 0.02.Among them,AdaBoost and CatBoost consistently outperformed the other methods across both the training and testing datasets,demonstrating superior generalizability and robustness.The proposed ML framework offers an efficient,accurate,and data-driven alternative to traditional methods for estimating caisson capacity in stratified soils.This approach can aid in reducing computational costs while improving reliability in the early stages of foundation design. 展开更多
关键词 Two-layered clay Open caisson Tree-based algorithms FELA Machine learning
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Path Planning for Thermal Power Plant Fan Inspection Robot Based on Improved A^(*)Algorithm 被引量:1
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作者 Wei Zhang Tingfeng Zhang 《Journal of Electronic Research and Application》 2025年第1期233-239,共7页
To improve the efficiency and accuracy of path planning for fan inspection tasks in thermal power plants,this paper proposes an intelligent inspection robot path planning scheme based on an improved A^(*)algorithm.The... To improve the efficiency and accuracy of path planning for fan inspection tasks in thermal power plants,this paper proposes an intelligent inspection robot path planning scheme based on an improved A^(*)algorithm.The inspection robot utilizes multiple sensors to monitor key parameters of the fans,such as vibration,noise,and bearing temperature,and upload the data to the monitoring center.The robot’s inspection path employs the improved A^(*)algorithm,incorporating obstacle penalty terms,path reconstruction,and smoothing optimization techniques,thereby achieving optimal path planning for the inspection robot in complex environments.Simulation results demonstrate that the improved A^(*)algorithm significantly outperforms the traditional A^(*)algorithm in terms of total path distance,smoothness,and detour rate,effectively improving the execution efficiency of inspection tasks. 展开更多
关键词 Power plant fans Inspection robot Path planning Improved A^(*)algorithm
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An Algorithm for Cloud-based Web Service Combination Optimization Through Plant Growth Simulation
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作者 Li Qiang Qin Huawei +1 位作者 Qiao Bingqin Wu Ruifang 《系统仿真学报》 北大核心 2025年第2期462-473,共12页
In order to improve the efficiency of cloud-based web services,an improved plant growth simulation algorithm scheduling model.This model first used mathematical methods to describe the relationships between cloud-base... In order to improve the efficiency of cloud-based web services,an improved plant growth simulation algorithm scheduling model.This model first used mathematical methods to describe the relationships between cloud-based web services and the constraints of system resources.Then,a light-induced plant growth simulation algorithm was established.The performance of the algorithm was compared through several plant types,and the best plant model was selected as the setting for the system.Experimental results show that when the number of test cloud-based web services reaches 2048,the model being 2.14 times faster than PSO,2.8 times faster than the ant colony algorithm,2.9 times faster than the bee colony algorithm,and a remarkable 8.38 times faster than the genetic algorithm. 展开更多
关键词 cloud-based service scheduling algorithm resource constraint load optimization cloud computing plant growth simulation algorithm
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一些与仿theta函数相关的函数
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作者 曲帅龙 《曲阜师范大学学报(自然科学版)》 2025年第2期33-40,共8页
在Ramanujan写给Hardy的最后一封信中,引入了17个经典仿theta函数,这些函数可以用欧拉形式、Hecke类型双重求和、Appell-Lerch求和以及亚纯Jocobi形式的傅里叶系数来表示.该文发现了与某些仿theta函数相关的4个新函数.同时构建了这些新... 在Ramanujan写给Hardy的最后一封信中,引入了17个经典仿theta函数,这些函数可以用欧拉形式、Hecke类型双重求和、Appell-Lerch求和以及亚纯Jocobi形式的傅里叶系数来表示.该文发现了与某些仿theta函数相关的4个新函数.同时构建了这些新函数的Hecke类型双重求和.最后建立了这些函数与一些经典仿theta函数之间的关系. 展开更多
关键词 仿theta函数 Hecke型双重求和 Appell-Lerch求和
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间歇性Theta节律经颅磁刺激在脑卒中后构音障碍康复中的应用效果
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作者 于艳梅 王宁 刘茵茵 《中华保健医学杂志》 2025年第5期851-854,共4页
目的 分析间歇性Theta节律经颅磁刺激(iTBS)在脑卒中后构音障碍(DAS)康复中的应用效果。方法 前瞻性选取2022年7月~2024年7月海军青岛特勤疗养中心神经康复科收治的DAS患者98例,随机数表法分为iTBS组(49例)、对照组(49例)。两组患者均... 目的 分析间歇性Theta节律经颅磁刺激(iTBS)在脑卒中后构音障碍(DAS)康复中的应用效果。方法 前瞻性选取2022年7月~2024年7月海军青岛特勤疗养中心神经康复科收治的DAS患者98例,随机数表法分为iTBS组(49例)、对照组(49例)。两组患者均予以言语治疗,iTBS组接受iTBS、对照组接受假iTBS,两组均康复治疗4周。比较两组患者康复治疗4周后疗效;比较两组患者康复治疗前后构音障碍综合性评价量表评分情况;比较两组患者发声情况、嗓音及交流能力。结果 康复治疗4周后,iTBS组总有效率高于对照组[85.71%(42/49)vs. 65.31%(32/49)],差异有统计学意义(χ^(2)=5.518,P<0.05)。康复治疗4周后,两组患者构音障碍综合性评价量表各维度、嗓音障碍指数(VHI)、声嘶听感知评定量表(GRBAS)评分降低,且iTBS组为低于对照组,差异有统计学意义(t=4.906、12.670、7.482、6.503、9.523、12.208、7.988、12.756、11.264、12.714,P<0.05)。康复治疗4周后两组语音清晰度、言语响度、交流有效性指数(CETI)评分、最长发声时间(MPT)升高,且iTBS组高于对照组,差异有统计学意义(t=11.649、2.134、21.649、7.398,P<0.05)。结论 iTBS联合言语治疗可显著改善DAS患者的言语功能,其疗效优于假iTBS联合言语治疗,在发声情况、嗓音及交流能力等方面均表现出更显著的改善,可能作为脑卒中后构音障碍康复治疗的有效辅助手段。 展开更多
关键词 脑卒中 构音障碍 间歇性theta节律经颅磁刺激 嗓音 交流能力
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间歇性Theta节律刺激配合核心肌群训练对脑卒中后偏瘫的影响
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作者 吴柳云 方志 +1 位作者 杨春花 汪道明 《河北医学》 2025年第3期495-500,共6页
目的:探究间歇性Theta节律刺激配合核心肌群训练在脑卒中后偏瘫患者中的应用效果。方法:选取2022年2月到2024年2月来医院就诊的79例脑卒中后偏瘫患者,采用回顾性分析研究按不同的治疗方法分为对照组(n=41例,常规治疗配合核心肌群训练)... 目的:探究间歇性Theta节律刺激配合核心肌群训练在脑卒中后偏瘫患者中的应用效果。方法:选取2022年2月到2024年2月来医院就诊的79例脑卒中后偏瘫患者,采用回顾性分析研究按不同的治疗方法分为对照组(n=41例,常规治疗配合核心肌群训练)和联合组(n=38例,对照组基础上给予间歇性Theta节律刺激),均治疗2周。观察比较两组患者治疗前后的神经功能指标[脑源性神经细胞营养因子(BDNF)、神经元特异性烯醇化酶(NSE)]、Berg平衡量表(BBS)、运动能力[Fugl-Meyer量表]、脑卒中专用生活质量量表(SS-QOL)评分。结果:治疗前,两组患者的神经功能指标、BBS、Fugl-Meye、SS-QOL评分相近(P>0.05),治疗前后,联合组BDNF、BBS评分、Fugl-Meye评分、SS-QOL评分升高幅度大于对照组,NSE降低幅度大于对照组(均P<0.05)。结论:采用间歇性Theta节律刺激配合核心肌群训练治疗脑卒中后偏瘫患者有显著疗效,有利于恢复患者神经功能,提高平衡性,增强运动能力,使患者的生活质量显著提高,有应用价值。 展开更多
关键词 间歇性theta节律刺激 核心肌群训练 脑卒中 偏瘫 神经功能
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