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我国专业学位研究生教育协同育人影响因素分析——基于PLS-SEM模型 被引量:2
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作者 张丽华 宁梦妍 王一然 《教育理论与实践》 北大核心 2025年第3期19-23,共5页
专业学位研究生教育是培养高层次应用型人才的重要途径。全面深化协同育人机制是促进专业学位研究生教育从有质量地发展到高质量发展的关键点和突破口。从高校、企业、政府三个利益相关主体出发,通过PLS-SEM模型分析我国专业学位研究生... 专业学位研究生教育是培养高层次应用型人才的重要途径。全面深化协同育人机制是促进专业学位研究生教育从有质量地发展到高质量发展的关键点和突破口。从高校、企业、政府三个利益相关主体出发,通过PLS-SEM模型分析我国专业学位研究生教育协同育人影响因素的研究结果表明:高等学校发表科技成果、政府对境内企业R&D支出以及企业科研人员占比对协同育人产生显著影响。为了更好地促进我国专业学位研究生教育协同育人的发展,应建立高校赋能新质生产力的协同育人机制、多主体共建数字化协同育人平台并发挥资源集聚效应提升协同育人成效。 展开更多
关键词 专业学位研究生教育 协同育人 pls-sem模型 高校 企业 政府
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基于PLS-SEM的渭河流域径流演变效应解耦
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作者 江善虎 江宏 +2 位作者 朱永卫 崔豪 任立良 《水资源保护》 北大核心 2025年第5期223-230,共8页
为定量解耦气候变化、人类活动与植被动态等多因素对流域水循环演变的影响,构建了渭河流域水循环多要素影响解耦框架;利用偏最小二乘结构方程模型(PLS-SEM)、Pearson相关分析与趋势分析法,解耦了1982—2020年渭河流域气候变化、人类活... 为定量解耦气候变化、人类活动与植被动态等多因素对流域水循环演变的影响,构建了渭河流域水循环多要素影响解耦框架;利用偏最小二乘结构方程模型(PLS-SEM)、Pearson相关分析与趋势分析法,解耦了1982—2020年渭河流域气候变化、人类活动、植被动态对渭河流域径流变化的直接和间接效应。结果表明:1982—2001年渭河流域气候变化与人类活动对径流影响的综合效应呈现均衡态势,气候变化和人类活动对径流的综合效应值分别为0.313、-0.315;2002—2020年人类活动的综合效应值(-0.667)显著超越气候变化(0.319),成为流域径流演变的主导驱动因素;1982—2001年径流减少的机制特征为降水主导、多因子协同,降水减少的直接效应与气温升高、植被恢复及人类活动的综合效应共同主导径流衰减过程;2002—2020年径流增加的机制特征为降水主控、工程消减,降水显著增加是导致径流增加的主导因素,而工程调控的直接效应抑制了径流增加的趋势,导致径流仅呈现微弱的恢复态势。 展开更多
关键词 气候变化 人类活动 植被动态 径流演变 pls-sem 渭河流域
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基于PLS-SEM模型的适老化橱柜设计影响因素分析
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作者 张玲玲 戴向东 +3 位作者 李佳莹 罗方 吕宙 肖文波 《中南林业科技大学学报》 北大核心 2025年第4期211-224,共14页
【目的】精准获取老年人对橱柜使用的需求,通过构建结构方程模型分析适老化橱柜设计的关键影响因素,为设计适老化橱柜及制定其产品市场营销策略提供重要的数据支持。【方法】以60岁以上的老年人为研究对象,采用问卷量表法,通过发放457... 【目的】精准获取老年人对橱柜使用的需求,通过构建结构方程模型分析适老化橱柜设计的关键影响因素,为设计适老化橱柜及制定其产品市场营销策略提供重要的数据支持。【方法】以60岁以上的老年人为研究对象,采用问卷量表法,通过发放457份有效问卷收集影响适老化橱柜设计的自变量指标数据,并运用李克特五级量表分析,量化各指标对适老化橱柜设计的影响度。从材料、尺寸、布局、功能、色彩和智能6个方面选取36项设计指标,以创新性作为中介变量,消费意愿作为因变量,通过偏最小二乘结构方程模型(PLS-SEM)对影响适老化橱柜设计的关键因素进行实证分析。【结果】1)在量表信效度检验中,布局、材料、尺寸、功能、色彩、智能、创新和消费8个维度的克隆巴赫系数均高于0.86,各测量题项间具有较强的内部关联性和一致性;组成信度均超过0.8,进一步证实量表具备高度的可靠性;平均抽取变异量(AVE)均高于0.7,显示出各变量具备良好的聚合效能,本研究构建的适老化橱柜设计测量模型在信度与效度方面均具有良好表现。2)采用amos软件对量表进行验证,区分效度检验各个维度所对应的AVE平方根都高于它与其他所有变量的相关系数的平方值,证明各变量之间具有良好的区分效度,检验成立。3)在PLS-SEM建模中显示构成各维度的因子荷载系数均较高,但不同指标在其所属维度内的荷载系数存在差异,应优先考虑荷载系数较高的指标,他们对潜在变量的解释能力更强。4)通过假设验证,H1~H6的路径系数均通过显著性检验(P<0.05),H7~H12对不同路径的间接效应通过显著性检验(P<0.05),表明先前假设在一定显著性水平下成立。【结论】研究结果得出一系列对适老化橱柜设计至关重要的影响因素,功能对购买意愿的影响系数最高,智能因素的影响系数相对较低,产品的功能特性是适老化橱柜设计最关键的因素之一,为适老化橱柜设计和市场营销策略的制定提供了理论依据。 展开更多
关键词 橱柜 适老化 智能化 适配性 pls-sem模型
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基于24Model的动火作业事故致因文本挖掘 被引量:1
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作者 牛茂辉 李威君 +1 位作者 刘音 王璐 《中国安全科学学报》 北大核心 2025年第3期151-158,共8页
为探究工业动火作业事故的根源,提出一种基于“2-4”模型(24Model)的文本挖掘方法。首先,收集整理220篇动火作业事故报告,并作为数据集,构建基于来自变换器的双向编码器表征量(BERT)的24Model分类器,使用预训练模型训练和评估事故报告... 为探究工业动火作业事故的根源,提出一种基于“2-4”模型(24Model)的文本挖掘方法。首先,收集整理220篇动火作业事故报告,并作为数据集,构建基于来自变换器的双向编码器表征量(BERT)的24Model分类器,使用预训练模型训练和评估事故报告数据集,构建分类模型;然后,通过基于BERT的关键字提取算法(KeyBERT)和词频-逆文档频率(TF-IDF)算法的组合权重,结合24Model框架,建立动火作业事故文本关键词指标体系;最后,通过文本挖掘关键词之间的网络共现关系,分析得到事故致因之间的相互关联。结果显示,基于BERT的24Model分类器模型能够系统准确地判定动火作业事故致因类别,通过组合权重筛选得到4个层级关键词指标体系,其中安全管理体系的权重最大,结合共现网络分析得到动火作业事故的7项关键致因。 展开更多
关键词 “2-4”模型(24model) 动火作业 事故致因 文本挖掘 指标体系
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基于PLS-SEM的生态系统健康变化及驱动因素分析——以京津冀地区为例
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作者 闫语 秦耀伟 +4 位作者 赵振宇 东嘉琪 李双江 曹建生 肖捷颖 《环境工程技术学报》 北大核心 2025年第4期1387-1397,共11页
明确区域生态系统健康时空变化及其驱动因素影响途径,对生态系统管理和恢复具有重要意义。基于“活力-组织-弹性-服务”模型,评估2000—2022年京津冀地区生态系统健康水平,从全局和分区(山区、平原)角度分析其动态演变特征,利用偏最小二... 明确区域生态系统健康时空变化及其驱动因素影响途径,对生态系统管理和恢复具有重要意义。基于“活力-组织-弹性-服务”模型,评估2000—2022年京津冀地区生态系统健康水平,从全局和分区(山区、平原)角度分析其动态演变特征,利用偏最小二乘-结构方程模型(PLS-SEM)分析人为与自然因素对生态系统健康的影响路径,运用最优参数地理探测器模型识别主要驱动因子。结果表明:2000—2022年京津冀地区生态系统健康呈改善趋势,其中山区持续增长,平原为先降后升,空间分布呈山区高平原低的特征,山区北部和西部生态系统健康改善显著;人类活动对生态系统健康产生的负面影响高于自然因素产生的正面影响,全局和山区的地形和植被覆盖产生较高正面影响,景观组成则产生了显著的直接负面影响,而社会经济因素产生间接负面影响;平原地区景观组成、地形和植被覆盖因素均产生较高的直接正面影响,社会经济则产生为显著负面影响。单因子分析表明,林地及建设用地占比、坡度和高程是全局生态系统健康的主要驱动因子,林地占比、耕地占比、建设用地占比和归一化植被指数为山区的主要驱动因子,而建设用地占比、归一化植被指数和夜间灯光为平原的主要驱动因子。建议基于山区与平原生态系统健康驱动因子分区施策,加强山区生态保护政策的实施,优化平原地区土地利用与植被覆盖,以实现区域生态可持续发展。 展开更多
关键词 生态系统健康 “活力-组织-弹性-服务”模型 驱动因素 偏最小二乘-结构方程模型(pls-sem) 京津冀地区
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高中生“原子结构”学习成效影响因素的PLS-SEM实证研究
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作者 金雄鹰 蒋永贵 《化学教学》 北大核心 2025年第11期20-26,共7页
采用PLS-SEM模型探讨高中生“原子结构”学习成效的影响因素,发现化学自我效能感、化学空间能力、学习态度、学习策略及教师支持是重要因素。化学空间能力对学习成效影响最大,同时化学自我效能感在多个关系中起中介作用。学习态度和学... 采用PLS-SEM模型探讨高中生“原子结构”学习成效的影响因素,发现化学自我效能感、化学空间能力、学习态度、学习策略及教师支持是重要因素。化学空间能力对学习成效影响最大,同时化学自我效能感在多个关系中起中介作用。学习态度和学习策略直接影响化学自我效能感和化学空间能力,进而影响学习成效。教师支持通过影响学习策略和态度对学习成效产生积极作用。研究建议教师要因材施教,强化空间能力训练,优化学生自我效能感,进而提高学习成效。 展开更多
关键词 原子结构 学习成效 影响因素 pls-sem模型
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Comparative study on the oblique water-entry of high-speed projectile based on rigid-body and elastic-plastic body model 被引量:2
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作者 Xiangyan Liu Xiaowei Cai +3 位作者 Zhengui Huang Yu Hou Jian Qin Zhihua Chen 《Defence Technology(防务技术)》 2025年第4期133-155,共23页
To examine the similarities and differences in the evolution of cavity,wetting and dynamics of a highspeed,oblique water-entry projectile with different positive angles of attack,a comparative analysis has been conduc... To examine the similarities and differences in the evolution of cavity,wetting and dynamics of a highspeed,oblique water-entry projectile with different positive angles of attack,a comparative analysis has been conducted based on the numerical results of two mathematical models,the rigid-body model and fluid-structure interaction model.In addition,the applicable scope of the above two methods,and the structural response characteristics of the projectile have also been investigated.Our results demonstrate that:(1) The impact loads and angular motion of the projectile of the rigid-body method are more likely to exhibit periodic variations due to the periodic tail slap,its range of positive angles of attack is about α<2°.(2) When the projectile undergone significant wetting,a strong coupling effect is observed among wetting,structural deformation,and projectile motion.With the applied projectile shape,it is observed that,when the projectile bends,the final wetting position is that of Part B(cylinder of body).With the occu rrence of this phenomenon,the projectile ballistics beco me completely unstable.(3) The force exerted on the lower surface of the projectile induced by wetting is the primary reason of the destabilization of the projectile traj ectory and structu ral deformation failure.Bending deformation is most likely to appear at the junction of Part C(cone of body) and Part D(tail).The safe angles of attack of the projectile stability are found to be about α≤2°. 展开更多
关键词 Fluid-structure interaction Rigid-body model Elastic-plastic model Structural deformation Impact loads Structural safety of projectile
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基于UTAUT2和PLS-SEM大语言模型平台的用户交互行为影响因素研究
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作者 崔鑫龙 王建华 +1 位作者 彭浩 陈渝 《印刷与数字媒体技术研究》 北大核心 2025年第5期78-90,共13页
大语言模型平台凭借高效的运算速率和智能交互表现而被各领域深度应用,但对其用户行为驱动机制的系统性认知尚缺乏深入理解。本研究通过探讨大语言模型平台用户交互行为影响因素及作用路径,解析关键变量间内生因素,揭示用户行为驱动机... 大语言模型平台凭借高效的运算速率和智能交互表现而被各领域深度应用,但对其用户行为驱动机制的系统性认知尚缺乏深入理解。本研究通过探讨大语言模型平台用户交互行为影响因素及作用路径,解析关键变量间内生因素,揭示用户行为驱动机制与多维路径效应。通过整合UTAUT2与TAM核心变量,形成理论框架并提出假设路径,以此构建基于偏最小二乘法结构方程模型(PLS-SEM)的分析模型,并采用Smart PLS 4.1分析问卷以验证各变量间解释效度和路径效应的作用机制。结果表明,感知有用性、感知易用性、社会影响和习惯对行为意愿具有显著正向影响,便利条件直接促发使用行为;而价值价格对行为意愿呈负向影响,行为意愿在各前因变量间起部分中介作用,便利条件通过“机会驱动”路径能直接触发使用行为。基于研究结果,提出优化环境支持、透明化成本结构、融合功能性与娱乐性的建议,为大语言模型平台用户行为优化提供理论框架与实践路径。 展开更多
关键词 大语言模型平台 UTAUT2 交互行为 pls-sem 使用意愿
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基于PLS-SEM的中国公立医院集体领导力评价工具验证
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作者 赵金红 刘庭芳 《中国医院》 北大核心 2025年第3期26-31,共6页
目的:对已构建的中国公立医院领导力评价指标体系进行验证,检验其信度和效度。方法:选取东部、中部和西部9所公立医院开展问卷调查,采用探索性因子分析、验证性因子分析和偏最小二乘法结构方程模型(PLS-SEM)对评价工具的信度和效度进行... 目的:对已构建的中国公立医院领导力评价指标体系进行验证,检验其信度和效度。方法:选取东部、中部和西部9所公立医院开展问卷调查,采用探索性因子分析、验证性因子分析和偏最小二乘法结构方程模型(PLS-SEM)对评价工具的信度和效度进行验证。结果:通过EFA得出评价工具的3个关键因素,分别是道德规范、领导特质和管理风格。PLS-SEM检验结果显示,管理风格、领导特质和道德规范对领导力的总效应分别为0.558、0.389和0.112,工作作风、团队建设、魅力、员工关怀、能力、价值观和人际关系的总效应分别为0.184、0.180、0.151、0.147、0.141、0.115和0.073。结论:本研究聚焦于中国公立医院领导班子集体领导力的科学测量,构建了以行为和能力为导向的公立医院集体领导力评价指标体系,量化了公立医院领导班子的领导力水平。从中层管理人员视角来评价医院领导班子的领导力,有助于中国医院领导力科学评估评价领域的发展。 展开更多
关键词 公立医院 领导力 评价工具 pls-sem
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Solubility and Thermodynamic Modeling of 3⁃Nitro⁃1,2,4⁃triazole⁃5⁃one(NTO)in Different Binary Solvents 被引量:1
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作者 GUO Hao-qi YANG Yu-lin 《含能材料》 北大核心 2025年第3期295-303,共9页
Using a dynamic laser monitoring technique,the solubility of 3-nitro-1,2,4-triazole-5-one(NTO)was investigated in two different binary systems,namely hydroxylamine nitrate(HAN)-water and boric acid(HB)-water ranging f... Using a dynamic laser monitoring technique,the solubility of 3-nitro-1,2,4-triazole-5-one(NTO)was investigated in two different binary systems,namely hydroxylamine nitrate(HAN)-water and boric acid(HB)-water ranging from 278.15 K to 318.15 K.The solubility in each system was found to be positively correlated with temperature.Furthermore,solubility data were analyzed using four equations:the modified Apelblat equation,Van’t Hoff equation,λh equation and CNIBS/R-K equations,and they provided satisfactory results for both two systems.The average root-mean-square deviation(105RMSD)values for these models were less than 13.93.Calculations utilizing the Van’t Hoff equation and Gibbs equations facilitated the derivation of apparent thermodynamic properties of NTO dissolution in the two systems,including values for Gibbs free energy,enthalpy and entropy.The%ζ_(H)is larger than%ζ_(TS),and all the%ζ_(H)data are≥58.63%,indicating that the enthalpy make a greater contribution than entropy to theΔG_(soln)^(Θ). 展开更多
关键词 3-nitro-l 2 4-triazole-5-one(NTO) SOLUBILITY thermodynamic models apparent thermodynamic analysis
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Investigation on the Ice Load on a Cylinder Vertically Breaking through Model Ice Sheet from Underneath
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作者 ZHAO Wei−hang TIAN Yu−kui +3 位作者 JI Shao−peng GANG Xu−hao YU Chao−ge KONG Shuai 《船舶力学》 北大核心 2025年第6期964-975,共12页
Ice load on underwater vehicles breaking through ice covers from underneath is a significant concern for researchers in polar exploration,and the research on this problem is still in its early stages.Both mechanical e... Ice load on underwater vehicles breaking through ice covers from underneath is a significant concern for researchers in polar exploration,and the research on this problem is still in its early stages.Both mechanical experimental measurement and numerical simulation pose research challenges.This study focuses on the ice load of a cylinder structure breaking upward through the ice sheet form underneath in the Small Ice Model Basin of China Ship Scientific Research Center(CSSRC SIMB).A high-speed camera system was employed to observe the ice sheet failure during the tests,in which,with the loading position as center,local radial cracks and circumferential cracks were generated.A load sensor was used to measure the overall ice load during this process.Meanwhile,a numerical model was developed using LS-DYNA for validation and comparison.With this model,numerical simulation was conducted under various ice thicknesses and upgoing speeds to analyze the instantaneous curves of ice load.The calculation results were statistically analyzed under different working conditions to determine the influence of the factors on the ice load of the cylinder.The study explores the measurement method about ice load of objects vertically breaking through model ice sheet and is expected to provide some fundamental insights into the safety design of underwater structures operating in ice waters. 展开更多
关键词 CYLINDER model test failure mode crack propagation ice load numerical modeling
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Dynamics of a Stochastic Epidemic Model with Age-group
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作者 LAN Xiaomin CHEN Guangmin +5 位作者 ZHOU Ruiyang ZHENG Kuicheng CAI Shaojian WEI Fengying JIN Zhen MAO Xuerong 《应用数学》 北大核心 2025年第1期294-307,共14页
A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,t... A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,the aging rates between two age groups are set to be constant.The existence-and-uniqueness of global positive solution is firstly showed.Then,by constructing several appropriate Lyapunov functions and using the high-dimensional Itô’s formula,the sufficient conditions for the stochastic extinction and stochastic persistence of the exposed individuals and the infected individuals are obtained.The stochastic extinction indicator and the stochastic persistence indicator are less-valued expressions compared with the basic reproduction number.Meanwhile,the main results of this study are modified into multi-age groups.Furthermore,by using the surveillance data for Fujian Provincial Center for Disease Control and Prevention,Fuzhou COVID-19 epidemic is chosen to carry out the numerical simulations,which show that the age group of the population plays the vital role when studying infectious diseases. 展开更多
关键词 Epidemic model Age groups PERSISTENCE EXTINCTION
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Mechanism of post cardiac arrest syndrome based on animal models of cardiac arrest
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作者 Halidan ABUDU WANG Yiping +10 位作者 HE Kang LIU Ziquan GUO Liqiong DONG Jinrui Ailijiang KADEER XU Guowu LIU Yanqing MENG Xiangyan CAI Jinxia LI Yongmao FAN Haojun 《中南大学学报(医学版)》 北大核心 2025年第5期731-746,共16页
Cardiac arrest(CA)is a critical condition in the field of cardiovascular medicine.Despite successful resuscitation,patients continue to have a high mortality rate,largely due to post CA syndrome(PCAS).However,the inju... Cardiac arrest(CA)is a critical condition in the field of cardiovascular medicine.Despite successful resuscitation,patients continue to have a high mortality rate,largely due to post CA syndrome(PCAS).However,the injury and pathophysiological mechanisms underlying PCAS remain unclear.Experimental animal models are valuable tools for exploring the etiology,pathogenesis,and potential interventions for CA and PCAS.Current CA animal models include electrical induction of ventricular fibrillation(VF),myocardial infarction,high potassium,asphyxia,and hemorrhagic shock.Although these models do not fully replicate the complexity of clinical CA,the mechanistic insights they provide remain highly relevant,including post-CA brain injury(PCABI),post-CA myocardial dysfunction(PAMD),systemic ischaemia/reperfusion injury(IRI),and the persistent precipitating pathology.Summarizing the methods of establishing CA models,the challenges encountered in the modeling process,and the mechanisms of PCAS can provide a foundation for developing standardized CA modeling protocols. 展开更多
关键词 cardiac arrest animal model post cardiac arrest syndrome PATHOPHYSIOLOGY modeling method
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Study on correlation of thermal model to in-orbit data for infrared optical payloads on FY-3E/HIRAS-Ⅱ
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作者 LI Yu-Han YANG Bao-Yu +4 位作者 ZHANG Qiang GUO Zhi-Peng WU Yi-Nong TANG Xiao LI Shang-Ju 《红外与毫米波学报》 北大核心 2025年第3期394-405,共12页
The Infrared Hyperspectral Atmospheric SounderⅡ(HIRAS-Ⅱ)is the key equipment on FengYun-3E(FY-3E)satellite,which can realize vertical atmospheric detection,featuring hyper spectral,high sensitivity and high precisio... The Infrared Hyperspectral Atmospheric SounderⅡ(HIRAS-Ⅱ)is the key equipment on FengYun-3E(FY-3E)satellite,which can realize vertical atmospheric detection,featuring hyper spectral,high sensitivity and high precision.To ensure its accuracy of detection,it is necessary to correlate their thermal models to in-orbit da⁃ta.In this work,an investigation of intelligent correlation method named Intelligent Correlation Platform for Ther⁃mal Model(ICP-TM)was established,the advanced Kriging surrogate model and efficient adaptive region opti⁃mization algorithm were introduced.After the correlation with this method for FY-3E/HIRAS-Ⅱ,the results indi⁃cate that compared with the data in orbit,the error of the thermal model has decreased from 5 K to within±1 K in cold case(10℃).Then,the correlated model is validated in hot case(20℃),and the correlated model exhibits good universality.This correlation precision is also much superiors to the general ones like 3 K in other similar lit⁃erature.Furthermore,the process is finished in 8 days using ICP-TM,the efficiency is much better than 3 months based on manual.The results show that the proposed approach significantly enhances the accuracy and efficiency of thermal model,this contributes to the precise thermal control of subsequent infrared optical payloads. 展开更多
关键词 thermal model intelligent correlation method surrogate model infrared optical payload FY-3E
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Modeling and sliding mode control based on inverse compensation of piezo-positioning system
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作者 LI Zhi-bin XIN Yuan-ze +1 位作者 ZHANG Jian-qiang SUN Chong-shang 《中国光学(中英文)》 北大核心 2025年第1期170-185,共16页
In order to enhance the control performance of piezo-positioning system,the influence of hysteresis characteristics and its compensation method are studied.Hammerstein model is used to represent the dynamic hysteresis... In order to enhance the control performance of piezo-positioning system,the influence of hysteresis characteristics and its compensation method are studied.Hammerstein model is used to represent the dynamic hysteresis nonlinear characteristics of piezo-positioning actuator.The static nonlinear part and dynamic linear part of the Hammerstein model are represented by models obtained through the Prandtl-Ishlinskii(PI)model and Hankel matrix system identification method,respectively.This model demonstrates good generalization capability for typical input frequencies below 200 Hz.A sliding mode inverse compensation tracking control strategy based on P-I inverse model and integral augmentation is proposed.Experimental results show that compared with PID inverse compensation control and sliding mode control without inverse compensation,the sliding mode inverse compensation control has a more ideal step response and no overshoot,moreover,the settling time is only 6.2 ms.In the frequency domain,the system closed-loop tracking bandwidth reaches 119.9 Hz,and the disturbance rejection bandwidth reaches 86.2 Hz.The proposed control strategy can effectively compensate the hysteresis nonlinearity,and improve the tracking accuracy and antidisturbance capability of piezo-positioning system. 展开更多
关键词 piezo-positioning system hysteresis nonlinearity Hammerstein model Prandtl-Ishlinskii(P-I)model system identification sliding mode control
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Millimeter-wave modeling based on transformer model for InP high electron mobility transistor
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作者 ZHANG Ya-Xue ZHANG Ao GAO Jian-Jun 《红外与毫米波学报》 北大核心 2025年第4期534-539,共6页
In this paper,the small-signal modeling of the Indium Phosphide High Electron Mobility Transistor(InP HEMT)based on the Transformer neural network model is investigated.The AC S-parameters of the HEMT device are train... In this paper,the small-signal modeling of the Indium Phosphide High Electron Mobility Transistor(InP HEMT)based on the Transformer neural network model is investigated.The AC S-parameters of the HEMT device are trained and validated using the Transformer model.In the proposed model,the eight-layer transformer encoders are connected in series and the encoder layer of each Transformer consists of the multi-head attention layer and the feed-forward neural network layer.The experimental results show that the measured and modeled S-parameters of the HEMT device match well in the frequency range of 0.5-40 GHz,with the errors versus frequency less than 1%.Compared with other models,good accuracy can be achieved to verify the effectiveness of the proposed model. 展开更多
关键词 transformer model neural network high electron mobility transistor(HEMT) small signal model
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Undrained mechanical behavior of unsaturated completely weathered granite:Experimental investigation and constitutive modeling 被引量:1
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作者 DU Shao-hua MA Jin-yin +2 位作者 RUAN Bo WU Gen-shui ZHANG Rui-chao 《Journal of Central South University》 2025年第6期2307-2327,共21页
The undrained mechanical behavior of unsaturated completely weathered granite(CWG)is highly susceptible to alterations in the hydraulic environment,particularly under uniaxial loading conditions,due to the unique natu... The undrained mechanical behavior of unsaturated completely weathered granite(CWG)is highly susceptible to alterations in the hydraulic environment,particularly under uniaxial loading conditions,due to the unique nature of this soil type.In this study,a series of unconfined compression tests were carried out on unsaturated CWG soil in an underground engineering site,and the effects of varying the environmental variables on the main undrained mechanical properties were analyzed.Based on the experimental results,a novel constitutive model was then established using the damage mechanics theory and the undetermined coefficient method.The results demonstrate that the curves of remolded CWG specimens with different moisture contents and dry densities exhibited diverse characteristics,including brittleness,significant softening,and ductility.As a typical indicator,the unconfined compression strength of soil specimens initially increased with an increase in moisture content and then decreased.Meanwhile,an optimal moisture content of approximately 10.5%could be observed,while a critical moisture content value of 13.0%was identified,beyond which the strength of the specimen decreases sharply.Moreover,the deformation and fracture of CWG specimens were predominantly caused by shear failure,and the ultimate failure modes were primarily influenced by moisture content rather than dry density.Furthermore,by comparing several similar models and the experimental data,the proposed model could accurately replicate the undrained mechanical characteristics of unsaturated CWG soil,and quantitatively describe the key mechanical indexes.These findings offer a valuable reference point for understanding the underlying mechanisms,anticipating potential risks,and implementing effective control measures in similar underground engineering projects. 展开更多
关键词 completely weathered granite undrained mechanical behavior environmental variable unconfined compression test constitutive model
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Fault-observer-based iterative learning model predictive controller for trajectory tracking of hypersonic vehicles 被引量:2
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作者 CUI Peng GAO Changsheng AN Ruoming 《Journal of Systems Engineering and Electronics》 2025年第3期803-813,共11页
This work proposes the application of an iterative learning model predictive control(ILMPC)approach based on an adaptive fault observer(FOBILMPC)for fault-tolerant control and trajectory tracking in air-breathing hype... This work proposes the application of an iterative learning model predictive control(ILMPC)approach based on an adaptive fault observer(FOBILMPC)for fault-tolerant control and trajectory tracking in air-breathing hypersonic vehicles.In order to increase the control amount,this online control legislation makes use of model predictive control(MPC)that is based on the concept of iterative learning control(ILC).By using offline data to decrease the linearized model’s faults,the strategy may effectively increase the robustness of the control system and guarantee that disturbances can be suppressed.An adaptive fault observer is created based on the suggested ILMPC approach in order to enhance overall fault tolerance by estimating and compensating for actuator disturbance and fault degree.During the derivation process,a linearized model of longitudinal dynamics is established.The suggested ILMPC approach is likely to be used in the design of hypersonic vehicle control systems since numerical simulations have demonstrated that it can decrease tracking error and speed up convergence when compared to the offline controller. 展开更多
关键词 hypersonic vehicle actuator fault tracking control iterative learning control(ILC) model predictive control(MPC) fault observer
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Design and validation of RLC equivalent circuit model based on long-wave infrared metamaterial absorber
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作者 ZHAO Ji-Cong DANG Yan-Meng +3 位作者 HOU Hai-Yang LIN Ye-Fan SUN Hai-Yan ZHANG Kun 《红外与毫米波学报》 北大核心 2025年第1期129-137,共9页
In this paper,we propose an RLC equivalent circuit model theory which can accurately predict the spectral response and resonance characteristics of metamaterial absorption structures,extend its design,and characterize... In this paper,we propose an RLC equivalent circuit model theory which can accurately predict the spectral response and resonance characteristics of metamaterial absorption structures,extend its design,and characterize the parameters of the model in detail.By employing this model,we conducted computations to characterize the response wavelength and bandwidth of variously sized metamaterial absorbers.A comparative analysis with Finite Difference Time Domain(FDTD)simulations demonstrated a remarkable level of consistency in the results.The designed absorbers were fabricated using micro-nano fabrication processes,and were experimentally tested to demonstrate absorption rates exceeding 90%at a wavelength of 9.28μm.The predicted results are then compared with test results.The comparison reveals good consistency in two aspects of the resonance responses,thereby confirming the rationality and accuracy of this model. 展开更多
关键词 METAMATERIAL surface plasmons magnetic dipoles RLC circuit model
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A literature review and outlook of advertising avoidance:An integrated theoretical framework based on the SOMR model
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作者 Shengliang Zhang Jianhui Jin Xiaodong Li 《中国科学技术大学学报》 北大核心 2025年第1期2-16,1,I0001,共17页
Advertising avoidance is resistance to advertising intrusion.This issue has been the subject of much academic research in recent years.To guide scholars to better carry out relevant research and promote enterprises to... Advertising avoidance is resistance to advertising intrusion.This issue has been the subject of much academic research in recent years.To guide scholars to better carry out relevant research and promote enterprises to better implement advertising activities,this study intends to summarize the relevant research on advertising avoidance in recent years.The specific method is to use the core literature meta-analysis method to identify,filter,and screen relevant literature published in core journals from 1997 to 2020 with the keywords advertising avoidance and advertising resistance.We review the collected articles from the following perspectives:the definition and classification,external stimulating factors,internal perception factors,and moderating factors of advertising avoidance.On this basis,the SOMR model of advertising avoidance is constructed according to the SOR model.Finally,some prospects for future related research are presented. 展开更多
关键词 ADVERTISING advertising avoidance SOMR model perceived value perceived infringement
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