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Bridging the gap:A scoping review of wet and dry lab simulation training in orthopaedic surgical education
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作者 Sari Wathiq Al Hajaj Chandramohan Ravichandran +4 位作者 Karthic Swaminathan Sanjeevi Bharadwaj Vishnu V Nair Hussein Shoukry Sriram Srinivasan 《World Journal of Orthopedics》 2026年第1期132-139,共8页
BACKGROUND Orthopaedic surgical education has traditionally depended on the apprenticeship model of“see one,do one,teach one”.However,reduced operative exposure,stricter work-hour regulations,medicolegal constraints... BACKGROUND Orthopaedic surgical education has traditionally depended on the apprenticeship model of“see one,do one,teach one”.However,reduced operative exposure,stricter work-hour regulations,medicolegal constraints,and patient safety concerns have constrained its practicality.Simulation-based training has become a reliable,safe,and cost-efficient alternative.Dry lab techniques,especially virtual and augmented reality,make up 78%of current dry lab research,whereas wet labs still set the standard for anatomical realism.AIM To evaluate the effectiveness,limitations,and future directions of wet and dry lab simulation in orthopaedic training.METHODS A scoping review was carried out across four databases-PubMed,Cochrane Library,Web of Science,and EBSCOhost-up to 2025.Medical Subject Headings included:"Orthopaedic Education","Wet Lab","Dry Lab","Simulation Training","Virtual Reality",and"Surgical Procedure".Eligible studies focused on orthopaedic or spinal surgical education,employed wet or dry lab techniques,and assessed training effectiveness.Exclusion criteria consisted of non-English publications,abstracts only,non-orthopaedic research,and studies unrelated to simulation.Two reviewers independently screened titles,abstracts,and full texts,resolving discrepancies with a third reviewer.RESULTS From 1851 records,101 studies met inclusion:78 on dry labs,7 on wet labs,4 on both.Virtual reality(VR)simulations were most common,with AI increasingly used for feedback and assessment.Cadaveric training remains the gold standard for accuracy and tactile feedback,while dry labs-especially VR-offer scalability,lower cost(40%-60%savings in five studies),and accessibility for novices.Senior residents prefer wet labs for complex tasks;juniors favour dry labs for basics.Challenges include limited transferability data,lack of standard outcome metrics,and ethical concerns about cadaver use and AI assessment.CONCLUSION Wet and dry labs each have unique strengths in orthopaedic training.A hybrid approach combining both,supported by standardised assessments and outcome studies,is most effective.Future efforts should aim for uniform reporting,integrating new technologies,and policy support for hybrid curricula to enhance skills and patient care. 展开更多
关键词 Orthopaedic education Wet lab Dry lab Simulation training Virtual reality Surgical procedure
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Advances in the application of virtual reality technology in ophthalmic surgical skills training
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作者 Jia-Wen Wei Qing Zhang +4 位作者 Xiao-Yan Wang Ming-Xue Huang Jin-Hua Gan Wei-Hua Yang Wei Chi 《International Journal of Ophthalmology(English edition)》 2026年第2期393-404,共12页
Conventional surgical teaching techniques face several challenges,highlighting a necessity for ongoing innovation in ophthalmology education to align with the evolving demands of clinical practice.The recent rapid adv... Conventional surgical teaching techniques face several challenges,highlighting a necessity for ongoing innovation in ophthalmology education to align with the evolving demands of clinical practice.The recent rapid advancement of computer technology has enabled the integration of virtual reality(VR)into medical training,thereby revolutionizing ophthalmic surgical education through VRbased educational methods.VR technology offers a safe,risk-free environment for trainees to practice repeatedly,enhancing surgical skills and accelerating the learning curve without compromising patient safety.This research outlines the application of VR technology in ophthalmic surgical skills training,particularly in cataract and vitreoretinal surgery.Including assessing the effectiveness of intraocular surgery training systems,evaluating skills transfer to the operating room,comparing it with wet lab cataract surgery training,and enhancing non-dominant hand training for cataract surgery,among other aspects.Additionally,this paper will identify the limitations of VR technology in ocular surgical skills training,offer improvement strategies,and detail the advantages and prospects,with the objective of guiding subsequent researchers. 展开更多
关键词 virtual reality OPHTHALMOLOGY ophthalmic surgical skills training surgical simulation cataract surgery vitreoretinal surgery
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Changing Tracks--The new CR450 train, currently in the testing phase, reaches speeds of 450 km/h thanks to technological advances
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作者 GE LIJUN 《ChinAfrica》 2026年第1期51-51,共1页
Safer,smarter,faster...In China,people prefer high-speed trains to flights if the journey time is under five hours.High-speed train travel is set to become even more attractive with the addition of a new member to the... Safer,smarter,faster...In China,people prefer high-speed trains to flights if the journey time is under five hours.High-speed train travel is set to become even more attractive with the addition of a new member to the high-speed train family:the CR450,the world’s fastest electric multiple unit(EMU). 展开更多
关键词 journey time electric multiple unit CR high speed trains FLIGHTS electric multiple unit emu
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基于车辆响应HHT和PSD相结合的桥梁损伤识别方法
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作者 方有亮 邢杰 +2 位作者 张颖 刘雪婷 刘丹阳 《河北大学学报(自然科学版)》 北大核心 2025年第5期458-465,共8页
传统的桥梁损伤检测方法通常在桥梁上布置大量的传感器,成本高,费时费力,限制了在实际工程中的应用.本文提出一种希尔伯特-黄变换(Hilbert-Huang transform,HHT)和功率谱密度(power spectral density,PSD)相结合的损伤识别方法,对桥梁... 传统的桥梁损伤检测方法通常在桥梁上布置大量的传感器,成本高,费时费力,限制了在实际工程中的应用.本文提出一种希尔伯特-黄变换(Hilbert-Huang transform,HHT)和功率谱密度(power spectral density,PSD)相结合的损伤识别方法,对桥梁进行损伤识别研究.首先,在测试车辆上布置1个加速度传感器,将车辆的加速度响应进行HHT变换,获取三维时频幅值谱;然后,利用该幅值谱的突变识别桥梁的损伤位置;最后,通过PSD识别桥梁的损伤程度α.结果表明,该方法不仅能够准确地识别桥梁的单损伤和多损伤位置,而且能够识别桥梁的损伤程度,识别精度较高,单损伤程度识别的最大误差为2.5%,多损伤程度识别的最大误差为2.6%. 展开更多
关键词 损伤识别 移动车辆响应 hht PSD
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商业银行基于Group Training技术的小样本学习应用研究
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作者 吴永飞 寿弘宇 +3 位作者 王彦博 魏文术 徐奇 张月 《金融科技时代》 2025年第3期16-22,共7页
人工智能是推动社会进步和经济发展的关键力量。商业银行已经在诸多业务领域广泛使用人工智能技术,如精准营销、智能风控、智慧运营等业务领域。然而,有些业务场景在“冷启动”阶段面临样本量不足,并且坏样本量极少的小样本学习问题,这... 人工智能是推动社会进步和经济发展的关键力量。商业银行已经在诸多业务领域广泛使用人工智能技术,如精准营销、智能风控、智慧运营等业务领域。然而,有些业务场景在“冷启动”阶段面临样本量不足,并且坏样本量极少的小样本学习问题,这导致现有的人工智能技术可能失效。基于此,文章创新提出了一种Group Training(群组训练)建模思路,可以有效解决小样本学习问题。实证结果表明,Group Training建模方案在多个金融数据集上效果均明显优于传统的建模方案,这为商业银行小样本学习提供了新的研究思路和解决方案。 展开更多
关键词 人工智能 小样本学习 Group Learning Group training
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基于CEEMD-HHT的公路隧道爆破洞外空气噪声时频能量分析
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作者 赵一聪 韩风雷 +1 位作者 肖东辉 张学富 《振动与冲击》 北大核心 2025年第4期198-206,共9页
为揭示隧道爆破噪声声源特性,给精准、科学的噪声污染防治提供理论基础,基于互补集合经验模态分解(complementary ensemble empirical mode decomposition,CEEMD)改进的希尔伯特-黄变换(Hilbert-Huang transform,HHT)方法分析了实测隧... 为揭示隧道爆破噪声声源特性,给精准、科学的噪声污染防治提供理论基础,基于互补集合经验模态分解(complementary ensemble empirical mode decomposition,CEEMD)改进的希尔伯特-黄变换(Hilbert-Huang transform,HHT)方法分析了实测隧道爆破空气噪声的时间-频率-能量特征,并运用统计学原理对所测系列噪声的主频带进行了估计。主要结论如下:①CEEMD-HHT法有效滤除了噪声信号中的无关高、低频分量;②隧道爆破噪声信号在幅值和能量方面都呈现瞬时脉冲特点,信号频带分布宽,频率成分丰富,但能量主要集中于低频段的窄带内;③宜采用基于主要能量分布特点确定的主频带描述爆破噪声信号特征;④所测系列爆破噪声的能量绝大部分(>95%)分布在80 Hz以下,次声波(<20 Hz)频段所含能量>30%。文章的研究结果可为隧道爆破噪声的源头防控提供理论指导。 展开更多
关键词 隧道爆破 爆破噪声 信号分析 希尔伯特-黄变换(hht)
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Low-Strain Damage Imaging Detection Experiment for Model Pile Integrity Based on HHT
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作者 Ziyang Jiang Ziping Wang +2 位作者 Kan Feng Yang Zhang Rahim Gorgin 《Structural Durability & Health Monitoring》 EI 2023年第6期557-569,共13页
With the advancement of computer and mathematical techniques,significant progress has been made in the 3D modeling of foundation piles.Existing methods include the 3D semi-analytical model for non-destructive low-stra... With the advancement of computer and mathematical techniques,significant progress has been made in the 3D modeling of foundation piles.Existing methods include the 3D semi-analytical model for non-destructive low-strain integrity assessment of large-diameter thin-walled pipe piles and the 3D soil-pile dynamic interaction model.However,these methods have complex analysis procedures and substantial limitations.This paper introduces an innovative and streamlined 3D imaging technique tailored for the detection of pile damage.The approach harnesses the power of an eight-channel ring array transducer to capture internal reflection signals within foundation piles.The acquired signals are subsequently processed using the Hilbert-Huang Transform(HHT),a robust analytical tool known for its effectiveness in handling non-stationary signals.Through the development of a sophisticated multi-channel ring array imaging algorithm,this technique empowers engineers and researchers to identify various pile defects,including their specific type,precise location,and obtain detailed 3D imaging representations.The findings of this research offer a valuable blend of theoretical insights and practical guidance,significantly advancing the state-of-the-art in the realm of concrete pile integrity inspection.By simplifying and enhancing the assessment process,this innovative approach not only addresses the complexities of existing methods but also contributes to the overall safety and reliability of concrete engineering structures. 展开更多
关键词 PILE integrity inspection annular array imaging hht
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基于时差的多输出tri-training异构软测量建模 被引量:2
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作者 王大芬 唐莉丽 +3 位作者 张鑫焱 聂春雨 李明珠 吴菁 《化工学报》 北大核心 2025年第3期1143-1155,共13页
软测量技术为工业过程中重要变量及难测变量的预测提供了一个有效的解决办法。然而,由于工业过程的复杂化和高昂的数据获取成本,使得标记数据与未标记数据分布不平衡。此时,构建高性能的软测量模型成为一个挑战。针对这一问题,提出了一... 软测量技术为工业过程中重要变量及难测变量的预测提供了一个有效的解决办法。然而,由于工业过程的复杂化和高昂的数据获取成本,使得标记数据与未标记数据分布不平衡。此时,构建高性能的软测量模型成为一个挑战。针对这一问题,提出了一种基于时差的多输出tri-training异构软测量方法。通过构建一种新的tri-training框架,采用多输出的高斯过程回归(multi-output Gaussian process regression,MGPR)、相关向量机(multi-output relevance vector machine,MRVM)、最小二乘支持向量机(multi-output least squares support vector machine,MLSSVM)三种模型作为基线监督回归器,使用标记数据进行训练和迭代;同时,引入时间差分(time difference,TD)改进模型的动态特性,并通过卡尔曼滤波(Kalman filtering,KF)优化模型的参数,提高其预测性能;最后通过模拟污水处理平台(benchmark simulation model 1,BSM1)和实际污水处理厂对该模型进行了验证。结果表明,与传统的软测量建模方法相比,该模型能显著提高数据分布不平衡下软测量模型的自适应性和预测性能。 展开更多
关键词 TRI-trainING 软测量 时间差分 协同训练 集成 预测 过程控制
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一种基于HHT的交直流微电网故障检测方案
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作者 张建文 包义玖 +3 位作者 臧甲杰 周剑桥 施刚 杨兴武 《电源学报》 北大核心 2025年第8期317-328,共12页
交直流微电网能够有效促进可再生能源的应用。然而,由于互联变换器的存在,交流和直流侧之间产生了较强的电气耦合,导致系统内故障特性更加复杂,严重影响系统安全运行。在交直流微电网中,传统的基于互联变换器IGBT闭锁后故障特征的故障... 交直流微电网能够有效促进可再生能源的应用。然而,由于互联变换器的存在,交流和直流侧之间产生了较强的电气耦合,导致系统内故障特性更加复杂,严重影响系统安全运行。在交直流微电网中,传统的基于互联变换器IGBT闭锁后故障特征的故障检测方案,在故障检测灵敏性和速动性方面难以满足系统的故障检测和保护需求。结合系统接地方式和交直流微电网的故障耦合特征,针对故障期间IGBT未闭锁暂态过程中交直流系统的特征形态,探索利用希尔伯特-黄变换HHT(Hilbert-Huang transform)频谱及能量幅值进行交直流微电网故障检测应用的可行性。通过仿真验证,所提基于HHT的故障检测方案能够实现2 ms内对交直流微电网故障类型的快速、准确识别,有效提高了微电网的安全性和可靠性。 展开更多
关键词 交直流微电网 互联变换器 故障耦合特性分析 希尔伯特-黄变换 故障检测
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基于改进型贝叶斯网络模型和HHT的电网故障诊断方法研究 被引量:1
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作者 伍冲翀 王健 龚黎慧倩 《电力科学与技术学报》 北大核心 2025年第2期42-49,共8页
电网安全稳定运行是其进行可靠输电、变电、配电的前提。当电网发生故障时,在故障区域进行快速、准确的定位对缩短故障时间十分重要。先从电网相关监测系统获取元件开关量和电气量信息,并根据故障区域形成相关开关量信息的初始决策表,... 电网安全稳定运行是其进行可靠输电、变电、配电的前提。当电网发生故障时,在故障区域进行快速、准确的定位对缩短故障时间十分重要。先从电网相关监测系统获取元件开关量和电气量信息,并根据故障区域形成相关开关量信息的初始决策表,提取电气量信息的有效信号;再采用粗糙集理论、贝叶斯网络、希尔伯特-黄变换(Hilbert-Huang transform,HHT)等理论,计算元件故障度和畸变度;然后,利用改进的D-S证据理论,对元件开关量的故障度与电气量的畸变度进行融合;最后,以某区域电网的局部拓扑为实例,对该改进型贝叶斯网络模型进行了仿真测试,该实例仿真结果表明该模型可提升算法诊断速度。并以IEEE 39节点为例进行了仿真,该仿真结果表明,开关量的引入可提升故障诊断精度,且融合数据降低了评估模型内的不确定程度。 展开更多
关键词 电网 粗糙集理论 贝叶斯网络 希尔伯特-黄变换 证据理论
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Research on optimization and evaluation method of heavy-haul train cyclic braking manipulation 被引量:1
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作者 Wen He Chongyi Chang +1 位作者 Lan Li Yupan Song 《Railway Sciences》 2025年第2期231-248,共18页
Purpose–The study aims to build a high-precision longitudinal dynamics model for heavy-haul trains and validate it with line test data,present an optimization method for multi-stage cyclic brakes based on the model a... Purpose–The study aims to build a high-precision longitudinal dynamics model for heavy-haul trains and validate it with line test data,present an optimization method for multi-stage cyclic brakes based on the model and conduct a multi-objective detailed evaluation of the driver’s manipulation during cyclic braking.Design/methodology/approach–The high-precision longitudinal train dynamics model was established and verified by the cyclic braking test data of the 20,000 t heavy-haul combination train on the long and steep downgrade.Then the genetic algorithm is employed for optimization subsequent to decoupling multiple cyclic braking procedures,with due consideration of driver operation rules.For evaluation,key manipulation assessments in the scenario are prioritized,supplemented by multi-objective evaluation requirements,and the computational model is employed for detailed evaluation analysis.Findings–Based on the model,experimental data reveal that the probability of longitudinal force error being less than 64.6 kN is approximately 68%,95%for less than 129.2 kN and 99.7%for less than 193.8 kN.Upon optimizing manipulations during the cyclic braking,the maximum reduction in coupler force spans from 21%∼23.9%.Andtheevaluation scoresimply that a proper elevationof the releasingspeed favorssafety.A high electric braking force,although beneficial to some extent for energy-saving,is detrimental to reducing coupler force.Originality/value–The results will provide a theoretical basis and practical guidance for further ensuring the safety and energy-efficient operation of heavy haul trains on long downhill sections and improving the operational quality of heavy-haul trains. 展开更多
关键词 Heavy-haul trains Longitudinal train dynamics Cyclic brake Manipulation optimization Detailed manipulation evaluation
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Intelligent human-computer interactive training assistant system for rail systems 被引量:1
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作者 Yuexuan Li Junhua Chen +1 位作者 Xiangyong Luo Han Zheng 《High-Speed Railway》 2025年第1期64-77,共14页
In recent years,railway construction in China has developed vigorously.With continuous improvements in the highspeed railway network,the focus is gradually shifting from large-scale construction to large-scale operati... In recent years,railway construction in China has developed vigorously.With continuous improvements in the highspeed railway network,the focus is gradually shifting from large-scale construction to large-scale operations.However,several challenges have emerged within the high-speed railway dispatching and command system,including the heavy workload faced by dispatchers,the difficulty of quantifying subjective expertise,and the need for effective training of professionals.Amid the growing application of artificial intelligence technologies in railway systems,this study leverages Large Language Model(LLM)technology.LLMs bring enhanced intelligence,predictive capabilities,robust memory,and adaptability to diverse real-world scenarios.This study proposes a human-computer interactive intelligent scheduling auxiliary training system built on LLM technology.The system offers capabilities including natural dialogue,knowledge reasoning,and human feedback learning.With broad applicability,the system is suitable for vocational education,guided inquiry,knowledge-based Q&A,and other training scenarios.Validation results demonstrate its effectiveness in auxiliary training,providing substantial support for educators,students,and dispatching personnel in colleges and professional settings. 展开更多
关键词 High-speed railway Dispatch training assistance Large language model Human-computer interactive training assistant system Reinforcement learning
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基于HHT的深厚基覆型边坡地震损伤模式研究
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作者 张宁 黄韬 +2 位作者 苏祝政 王静 席呈虎 《铁道建筑》 北大核心 2025年第7期140-146,共7页
为探明地震作用下深厚基覆型边坡的失稳机制,以西南山区某深厚基覆型边坡为依托,构建含双层覆盖层的边坡测试模型并开展了振动台试验。基于希尔伯特黄变换(Hilbert-Huang Transform,HHT)方法获取了不同覆盖层和基岩的时域-频域-幅值特征... 为探明地震作用下深厚基覆型边坡的失稳机制,以西南山区某深厚基覆型边坡为依托,构建含双层覆盖层的边坡测试模型并开展了振动台试验。基于希尔伯特黄变换(Hilbert-Huang Transform,HHT)方法获取了不同覆盖层和基岩的时域-频域-幅值特征,结合观测到的边坡破坏现象,揭示了边坡地震损伤模式的内在机理。结果表明:HHT方法可以有效分析地震作用下深厚基覆型边坡的破坏模式。地震作用下浅表层、厚覆盖层和基岩之间一直存在频率差,这种频率差引发了土层间的非一致性运动,从而诱发滑坡;浅表层与厚覆盖层的地震波能量传递差异一直存在,并且随地震动强度的增加而增大,这加剧了浅表层的非一致性滑动。 展开更多
关键词 铁路边坡 损伤破坏模式 hht 基覆型边坡 振动台试验
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Anti-obesity drugs alone or combined with exercise training in the management of obesity:a systematic review with meta-analysis 被引量:1
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作者 Bruna Marmett Igor da Silva +1 位作者 Fabio Lira Gilson Dorneles 《Translational Exercise Biomedicine》 2025年第1期51-62,共12页
Here we compare the efficacy of anti-obesity drugs alone or combined with exercise training on body weight and exercise capacity of obese patients.Randomized clinical trials that assessed the impact of any anti-obesit... Here we compare the efficacy of anti-obesity drugs alone or combined with exercise training on body weight and exercise capacity of obese patients.Randomized clinical trials that assessed the impact of any anti-obesity drug alone or combined with exercise training on body weight,body fat,fat-free mass and cardiorespiratory fitness in obese patients were retrieved from Pubmed and EMBASE up to May 2024.Risk of bias assessment was performed with RoB 2.0,and the GRADE approach assessed the certainty of evidence(CoE)of each main outcome.We included four publications summing up 202 patients.Two publications used orlistat as an anti-obesity drug treatment,while the other two adopted GLP-1 receptor agonist(liraglutide or tirzepatide)as a pharmacotherapy for weight management.Orlistat combined with exercise was superior to change body weight(mean difference(MD):−2.27 kg;95%CI:−2.86 to−1.69;CoE:very low),fat mass(MD:−2.89;95%CI:−3.87 to−1.91;CoE:very low),fat-free mass(MD:0.56;95%CI:0.40–0.72;CoE:very low),and VO_(2)Peak(MD:2.64;95%CI:2.52–2.76;CoE:very low).GLP-1 receptor agonist drugs combined with exercise had a great effect on body weight(MD:−3.96 kg;95%CI:−5.07 to−2.85;CoE:low),fat mass(MD:−1.76;95%CI:−2.24 to−1.27;CoE:low),fat-free mass(MD:0.50;95%CI:−0.98 to 1.98;CoE:very low)and VO_(2)Peak(MD:2.47;95%CI:1.31–3.63;CoE:very low).The results reported here suggest that exercise training remains an important approach in weight management when combined with pharmacological treatment. 展开更多
关键词 body weight PHARMACOTHERAPY physical training OBESITY
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Effects of exercise-cognitive dual-task training on elderly patients with cognitive frailty and depression 被引量:2
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作者 Ying Zhou Xiao-Ming Miao +4 位作者 Kai-Lian Zhou Cheng-Ji Yu Ping Lu Yin Lu Juan Zhao 《World Journal of Psychiatry》 2025年第4期149-159,共11页
BACKGROUND Cognitive frailty and depression are prevalent among the elderly,significantly impairing physical and cognitive functions,psychological well-being,and quality of life.Effective interventions are essential t... BACKGROUND Cognitive frailty and depression are prevalent among the elderly,significantly impairing physical and cognitive functions,psychological well-being,and quality of life.Effective interventions are essential to mitigate these adverse effects and enhance overall health outcomes in this population.AIM To evaluate the effects of exercise-cognitive dual-task training on frailty,cognitive function,psychological status,and quality of life in elderly patients with cognitive frailty and depression.METHODS A retrospective study was conducted on 130 patients with cognitive frailty and depression admitted between December 2021 and December 2023.Patients were divided into a control group receiving routine intervention and an observation group undergoing exercise-cognitive dual-task training in addition to routine care.Frailty,cognitive function,balance and gait,psychological status,and quality of life were assessed before and after the intervention.RESULTS After the intervention,the frailty score of the observation group was(5.32±0.69),lower than that of the control group(5.71±0.55).The Montreal cognitive assessment basic scale score in the observation group was(24.06±0.99),higher than the control group(23.43±1.40).The performance oriented mobility assessment score in the observation group was(21.81±1.24),higher than the control group(21.15±1.26).The self-efficacy in the observation group was(28.27±2.66),higher than the control group(30.05±2.66).The anxiety score in the hospital anxiety and depression scale(HADS)for the observation group was(5.86±0.68),lower than the control group(6.21±0.64).The depression score in the HADS for the observation group was(5.67±0.75),lower than the control group(6.27±0.92).Additionally,the scores for each dimension of the 36-item short form survey in the observation group were higher than those in the control group,with statistically significant differences(P<0.05).CONCLUSION Exercise-cognitive dual-task training is beneficial for improving frailty,enhancing cognitive function,and improving psychological status and quality of life in elderly patients with cognitive frailty and depression. 展开更多
关键词 Exercise-cognitive dual-task training Elderly patients Cognitive frailty Depression patients Frailty score Cognitive function
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A Surrogate-assisted Multi-objective Grey Wolf Optimizer for Empty-heavy Train Allocation Considering Coordinated Line Utilization Balance 被引量:1
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作者 Zhigang Du Shaoquan Ni +1 位作者 Jeng-Shyang Pan Shuchuan Chu 《Journal of Bionic Engineering》 2025年第1期383-397,共15页
This paper introduces the Surrogate-assisted Multi-objective Grey Wolf Optimizer(SMOGWO)as a novel methodology for addressing the complex problem of empty-heavy train allocation,with a focus on line utilization balanc... This paper introduces the Surrogate-assisted Multi-objective Grey Wolf Optimizer(SMOGWO)as a novel methodology for addressing the complex problem of empty-heavy train allocation,with a focus on line utilization balance.By integrating surrogate models to approximate the objective functions,SMOGWO significantly improves the efficiency and accuracy of the optimization process.The effectiveness of this approach is evaluated using the CEC2009 multi-objective test function suite,where SMOGWO achieves a superiority rate of 76.67%compared to other leading multi-objective algorithms.Furthermore,the practical applicability of SMOGWO is demonstrated through a case study on empty and heavy train allocation,which validates its ability to balance line capacity,minimize transportation costs,and optimize the technical combination of heavy trains.The research highlights SMOGWO's potential as a robust solution for optimization challenges in railway transportation,offering valuable contributions toward enhancing operational efficiency and promoting sustainable development in the sector. 展开更多
关键词 Surrogate-assisted model Grey wolf optimizer Multi-objective optimization Empty-heavy train allocation
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基于HHT的海拉尔地震监测中心站连续重力观测背景噪声分析
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作者 邹鑫慈 王怡 +6 位作者 谭圆梦 金志辉 叶子青 吴桐 堵伟鹏 周金玲 申影 《地震科学进展》 2025年第8期472-476,共5页
以海拉尔地震监测中心站PET重力仪2021—2023年连续观测数据为研究对象,利用Tsoft软件对原始连续重力数据预处理,获取重力残差数据。通过HHT (Hilbert-Huang Transform)方法对重力残差数据进行时频分析,总结台站连续重力数据背景噪声频... 以海拉尔地震监测中心站PET重力仪2021—2023年连续观测数据为研究对象,利用Tsoft软件对原始连续重力数据预处理,获取重力残差数据。通过HHT (Hilbert-Huang Transform)方法对重力残差数据进行时频分析,总结台站连续重力数据背景噪声频谱特征,得出海拉尔站连续重力观测背景噪声主要集中在0.05~0.28 Hz频段,优势频率为0.23 Hz。此研究有助于识别重力资料正常观测背景和干扰特征,为分析地震异常信息提供背景依据。 展开更多
关键词 连续重力 hht 背景噪声
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基于小波分解和HHT变换的运载火箭截面动载荷识别
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作者 王檑 姜人伟 +2 位作者 胡鹏翔 高艺航 王明杰 《宇航总体技术》 2025年第1期41-46,共6页
运载火箭截面动载荷难以直接测量,利用飞行过载、低频振动等遥测数据进行反向辨识是一种有效方法。针对在火箭低频模态较为密集时小波分解和HHT变换存在的频率混叠和模态混叠等问题,提出一种结合小波分解和HHT变换的识别方法。首先根据... 运载火箭截面动载荷难以直接测量,利用飞行过载、低频振动等遥测数据进行反向辨识是一种有效方法。针对在火箭低频模态较为密集时小波分解和HHT变换存在的频率混叠和模态混叠等问题,提出一种结合小波分解和HHT变换的识别方法。首先根据运载火箭模态计算结果,利用小波分解将振动信号分解到火箭低阶振动的频率范围;然后利用经验模态分解(Empirical Mode Decomposition,EMD)对小波分解后信号进行经验模态分解,通过希尔伯特变换计算每个分量的瞬时频率,对某一阶箭体振动,考虑一定频率偏差,将在此阶火箭固有频率附近的分量进行叠加,得到火箭在不同阶模态下的振动;最后利用模态叠加原理得到箭体各截面动载荷。对遥测数据进行了动载荷识别,识别结果约为设计值的30%,具有重要的工程应用价值。 展开更多
关键词 运载火箭 动载荷识别 小波分解 hht变换 遥测数据
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Aerodynamics and countermeasures of train-tail swaying inside single-line tunnels 被引量:1
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作者 Yadong SONG Yanpeng ZOU +2 位作者 Yuan YAO Ting QIN Longjiang SHEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第5期438-455,共18页
In recent years,train-tail swaying of 160 km/h electric multiple units(EMUs)inside single-line tunnels has been heavily researched,because the issue needs to be solved urgently.In this paper,a co-simulation model of v... In recent years,train-tail swaying of 160 km/h electric multiple units(EMUs)inside single-line tunnels has been heavily researched,because the issue needs to be solved urgently.In this paper,a co-simulation model of vortex-induced vibration(VIV)of the tail car body is established,and the aerodynamics of train-tail swaying is studied.The simulation results were confirmed through a field test of operating EMUs.Furthermore,the influence mechanism of train-tail swaying on the wake flow field is studied in detail through a wind-tunnel experiment and a simulation of a reduced-scaled train model.The results demonstrate that the aerodynamic force frequency(i.e.,vortex-induced frequency)of the train tail increases linearly with train speed.When the train runs at 130 km/h,with a small amplitude of train-tail swaying(within 10 mm),the vortex-induced frequency is 1.7 Hz,which primarily depends on the nose shape of the train tail.After the tail car body nose is extended,the vortex-induced frequency is decreased.As the swaying amplitude of the train tail increases(exceeding 25 mm),the separation point of the high-intensity vortex in the train wake shifts downstream to the nose tip,and the vortex-induced frequency shifts from 1.7 Hz to the nearby car body hunting(i.e.,the primary hunting)frequency of 1.3 Hz,which leads to the frequency-locking phenomenon of VIV,and the resonance intensifies train-tail swaying.For the motor vehicle of the train tail,optimization of the yaw damper to improve its primary hunting stability can effectively alleviate train-tail swaying inside single-line tunnels.Optimization of the tail car body nose shape reduces the amplitude of the vortex-induced force,thereby weakening the aerodynamic effect and solving the problem of train-tail swaying inside the single-line tunnels. 展开更多
关键词 train tail swaying wind tunnel experiment field test single line tunnels AERODYNAMICS co simulation electric multiple units emus inside vortex induced vibration
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A review of artificial intelligence in train driving and control
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作者 Yunxiang Xie Huachang Yang 《Railway Sciences》 2025年第6期762-782,共21页
Purpose–In recent years,the rapid advancement of artificial intelligence(AI)has exerted profound impacts on and provided strong impetus to numerous fields in the industrial sector.Within the railway industry,AI has d... Purpose–In recent years,the rapid advancement of artificial intelligence(AI)has exerted profound impacts on and provided strong impetus to numerous fields in the industrial sector.Within the railway industry,AI has driven continuous upgrading and optimization of intelligent train control technology,thanks to its enhanced computational capabilities derived from advanced algorithms and models,as well as its role in improving safety performance.Integrating AI technology more extensively into train autonomous driving and control has thus become an inevitable trend in the global development of railways.Design/methodology/approach–This paper,therefore,conducts a comprehensive analysis of the development progress and current status of AI technology applications in the field of train driving and control on a global scale.It systematically sorts out and analyzes the advantages of various AI technologies and the positive impacts they bring to the upgrading of train control technology,elucidates the feasibility and future prospects of applying a range of emerging AI technologies from the perspective of technical theory and provides guidance for the intelligent development of this field from a practical perspective.Findings–The application of AI technology in the train driving and control field is still in its infancy.While a large number of AI technologies have been widely adopted,there remains significant room for further optimization and improvement of these technologies.Additionally,a variety of AI technologies that have been applied in other industrial sectors but not yet widely implemented in training autonomous driving and control have demonstrated tremendous development potential.Originality/value–The research findings provide references and guidance for advancing train control technology,promoting the digital transformation of railways,accelerating the overall optimization and upgrading of railway industry technologies,and facilitating the accelerated development of global railways. 展开更多
关键词 Autonomous train driving Artificial intelligence train control train safety Quantum computing
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