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Isogeometric Analysis with Local Adaptivity for Vibration of Kirchhoff Plate
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作者 Peng Yu Weijing Yun +1 位作者 Junlei Tang Sheng He 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第5期949-978,共30页
Based on our proposed adaptivity strategy for the vibration of Reissner-Mindlin plate,we develop it to apply for the vibration of Kirchhoff plate.The adaptive algorithm is based on the Geometry-Independent Field appro... Based on our proposed adaptivity strategy for the vibration of Reissner-Mindlin plate,we develop it to apply for the vibration of Kirchhoff plate.The adaptive algorithm is based on the Geometry-Independent Field approximaTion(GIFT),generalized from Iso-Geometric Analysis(IGA),and it can characterize the geometry of the structure with NURBS(Non-Uniform Rational B-Splines),and independently apply PHT-splines(Polynomial splines over Hierarchical T-meshes)to achieve local refinement in the solution field.TheMAC(Modal AssuranceCriterion)is improved to locate unique,as well as multiple,modal correspondence between different meshes,in order to deal with error estimation.Local adaptivity is carried out by sweeping modes from low to high frequency.Numerical examples showthat a proper choice of the spline space in solution field(with GIFT)can deliver better accuracy than using NURBS solution field.In addition,for vibration of heterogeneous Kirchhoff plates,our proposed method indicates that the adaptive local h-refinement achieves a better solution accuracy than the uniform h-refinement. 展开更多
关键词 Isogeometric analysis local refinement adaptivity VIBRATION kirchhoff plate
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h-ADAPTIVITY ANALYSIS BASED ON MULTIPLE SCALE REPRODUCING KERNEL PARTICLE METHOD 被引量:4
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作者 ZHANG Zhi-qian(张智谦) ZHOU Jin-xiong(周进雄) +2 位作者 WANG Xue-ming(王学明) ZHANG Yan-fen(张艳芬) ZHANG Ling(张陵) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第8期1064-1071,共8页
An h-adaptivity analysis scheme based on multiple scale reproducing kernel particle method was proposed, and two node refinement strategies were constructed using searching-neighbor-nodes(SNN) and local-Delaunay-tri... An h-adaptivity analysis scheme based on multiple scale reproducing kernel particle method was proposed, and two node refinement strategies were constructed using searching-neighbor-nodes(SNN) and local-Delaunay-triangulation(LDT) techniques, which were suitable and effective for h-adaptivity analysis on 2-D problems with the regular or irregular distribution of the nodes. The results of multiresolution and h- adaptivity analyses on 2-D linear elastostatics and bending plate problems demonstrate that the improper high-gradient indicator will reduce the convergence property of the h- adaptivity analysis, and that the efficiency of the LDT node refinement strategy is better than SNN, and that the presented h-adaptivity analysis scheme is provided with the validity, stability and good convergence property. 展开更多
关键词 meshfree method reproducing kernel particle method multiresolution analysis adaptive analysis
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Mobile Devices Interface Adaptivity Using Ontologies
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作者 Muhammad Waseem Iqbal Muhammad Raza Naqvi +2 位作者 Muhammad Adnan Khan Faheem Khan T.Whangbo 《Computers, Materials & Continua》 SCIE EI 2022年第6期4767-4784,共18页
Currently,many mobile devices provide various interaction styles and modes which create complexity in the usage of interfaces.The context offers the information base for the development of Adaptive user interface(AUI)... Currently,many mobile devices provide various interaction styles and modes which create complexity in the usage of interfaces.The context offers the information base for the development of Adaptive user interface(AUI)frameworks to overcome the heterogeneity.For this purpose,the ontological modeling has been made for specific context and environment.This type of philosophy states to the relationship among elements(e.g.,classes,relations,or capacities etc.)with understandable satisfied representation.The contextmechanisms can be examined and understood by anymachine or computational framework with these formal definitions expressed in Web ontology language(WOL)/Resource description frame work(RDF).The Protégéis used to create taxonomy in which system is framed based on four contexts such as user,device,task and environment.Some competency questions and use-cases are utilized for knowledge obtaining while the information is refined through the instances of concerned parts of context tree.The consistency of the model has been verified through the reasoning software while SPARQL querying ensured the data availability in the models for defined use-cases.The semantic context model is focused to bring in the usage of adaptive environment.This exploration has finished up with a versatile,scalable and semantically verified context learning system.This model can be mapped to individual User interface(UI)display through smart calculations for versatile UIs. 展开更多
关键词 User context adaptive interfaces human computer interaction
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A New Efficient Explicit Deferred Correction Framework:Analysis and Applications to Hyperbolic PDEs and Adaptivity
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作者 Lorenzo Micalizzi Davide Torlo 《Communications on Applied Mathematics and Computation》 EI 2024年第3期1629-1664,共36页
The deferred correction(DeC)is an iterative procedure,characterized by increasing the accuracy at each iteration,which can be used to design numerical methods for systems of ODEs.The main advantage of such framework i... The deferred correction(DeC)is an iterative procedure,characterized by increasing the accuracy at each iteration,which can be used to design numerical methods for systems of ODEs.The main advantage of such framework is the automatic way of getting arbitrarily high order methods,which can be put in the Runge-Kutta(RK)form.The drawback is the larger computational cost with respect to the most used RK methods.To reduce such cost,in an explicit setting,we propose an efcient modifcation:we introduce interpolation processes between the DeC iterations,decreasing the computational cost associated to the low order ones.We provide the Butcher tableaux of the new modifed methods and we study their stability,showing that in some cases the computational advantage does not afect the stability.The fexibility of the novel modifcation allows nontrivial applications to PDEs and construction of adaptive methods.The good performances of the introduced methods are broadly tested on several benchmarks both in ODE and PDE contexts. 展开更多
关键词 Efficient deferred correction(DeC) Arbitrary high order STABILITY Adaptive methods Hyperbolic PDEs
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Conformal Metamaterials with Active Tunability and Self-Adaptivity for Magnetic Resonance Imaging
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作者 Ke Wu Xia Zhu +2 位作者 Xiaoguang Zhao Stephan W.Anderson Xin Zhang 《Research》 2025年第3期719-730,共12页
Metamaterials hold great potential to enhance the imaging performance of magnetic resonance imaging(MRI)as auxiliary devices,due to their unique ability to confine and enhance electromagnetic fields.Despite their prom... Metamaterials hold great potential to enhance the imaging performance of magnetic resonance imaging(MRI)as auxiliary devices,due to their unique ability to confine and enhance electromagnetic fields.Despite their promise,the current implementation of metamaterials faces obstacles for practical clinical adoption due to several notable limitations,including their bulky and rigid structures,deviations from optimal resonance frequency,and inevitable interference with the radiofrequency(RF)transmission field in MRI.Herein,we address these restrictions by introducing a flexible and smart metamaterial that enhances sensitivity by conforming to patient anatomies while ensuring comfort during MRI procedures.The proposed metamaterial selectively amplifies the magnetic field during the RF reception phase by passively sensing the excitation signal strength,remaining“off”during the RF transmission phase.Additionally,the metamaterial can be readily tuned to achieve a precise frequency match with the MRI system through a controlling circuit.The metamaterial presented here paves the way for the widespread utilization of metamaterials in clinical MRI,thereby translating this promising technology to the MRI bedside. 展开更多
关键词 magnetic resonance imaging auxiliary devicesdue confine enhance electromagnetic fieldsdespite patient anatomies magnetic resonance imaging mri self adaptivity sensitivity enhancement conformal metamaterials
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基于自适应模型预测控制的电机低温辅热优化
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作者 田华 陈英才 哈迪 《上海汽车》 2026年第3期31-36,共6页
针对目前新能源汽车在低温工况下充电效率低的问题,提出了一种基于电机堵转的自适应模型预测控制策略,涉及的硬件主要包含主驱电机、油泵、换热器(SPHE)、六通阀等部件。在低温工况下采用电机堵转发热的方式向外传递热量,油泵驱动冷却... 针对目前新能源汽车在低温工况下充电效率低的问题,提出了一种基于电机堵转的自适应模型预测控制策略,涉及的硬件主要包含主驱电机、油泵、换热器(SPHE)、六通阀等部件。在低温工况下采用电机堵转发热的方式向外传递热量,油泵驱动冷却油从电机向SPHE传递热量,SPHE将油路的热量通过热交换传递给水路,最终水路的热量通过六通阀传递至电池包水路,完成电池包的加热。在整个传热过程中,采用自适应模型预测控制算法,基于电机和机油温升特性,对油泵转速进行控制,最大化电机到油路的传热效率,从而达到最优化控制电池包升温的目的,解决低温电池包充电效率低的问题。 展开更多
关键词 新能源汽车驱动电机 低温充电 电机堵转 油泵控制 自适应模型预测控制(Adaptive MPC)
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基于LoRA标签优化的敦煌藻井图案AI生成式设计研究
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作者 孟欣怡 殷晓晨 赵毅龙 《包装工程》 北大核心 2026年第2期197-210,共14页
目的将设计学的方法融入AI生成式设计流程,通过提取LoRA训练集特征优化标签内容,增强LoRA风格迁移效果。方法以敦煌藻井图案为例,构建训练集。首先,通过结构、纹样元素分析,色彩聚类和感性工学实验,提取样本既定的图像特征和能概括样本... 目的将设计学的方法融入AI生成式设计流程,通过提取LoRA训练集特征优化标签内容,增强LoRA风格迁移效果。方法以敦煌藻井图案为例,构建训练集。首先,通过结构、纹样元素分析,色彩聚类和感性工学实验,提取样本既定的图像特征和能概括样本风格的感性词汇;其次,基于眼动追踪技术对藻井图案中纹样元素的特征性进行量化分析,根据视觉显著性对纹样排序;最后,将特征提取结果转换为自然语言,对训练集手动标注。结果对比分析了优化标签文本前后使用LoRA模型的生成内容,结果显示,优化后的模型再现训练集样本风格特征和纹样内容的能力更好。结论通过结合定性和定量方法,能够客观全面提取训练集特征,有效优化标签文本,提高使用LoRA模型生成内容的稳定性,进而通过智能设计推动传统纹样的创新与发展。 展开更多
关键词 Low-Rank Adaptation(LoRA) 图像标注 眼动实验 感性工学 敦煌藻井图案
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Metabolic adaptations of Qingke:A review of stress resilience and nutritional functions 被引量:2
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作者 Congping Xu Yulin Wang +19 位作者 Naoxue Fei Yuzhen Basang Haizhen Yang Jiabu Dunzhu Hongjun Yuan Mu Wang Sang Zha Wa Da Taba Xiongnu Puci Basang Chunbao Yang Qijun Xu Zexiu Wei Yawen Gan Yawei Tang Alisdair R.Fernie Zhaoyan Chen Jie Luo Ganggang Guo Xingquan Zeng 《The Crop Journal》 2026年第1期61-73,共13页
Qingke,a staple crop grown on the high-altitude Tibetan Plateau,has evolved a metabolomic profile providing both environmental stress resilience and human nutrition.We review the hypothesis that the metabolites that c... Qingke,a staple crop grown on the high-altitude Tibetan Plateau,has evolved a metabolomic profile providing both environmental stress resilience and human nutrition.We review the hypothesis that the metabolites that confer cold and UV resistance on the crop also facilitate human adaptation to high-altitude stresses.Specifically,β-glucans regulate blood glucose primarily via short-chain fatty acids(SCFAs)produced through gut microbiota fermentation,which directly mediate glucose homeostasis.Phenolamides accumulate via the phenylpropanoid pathway,with chalcone isomerase(CHI)serving as a key enzyme in flavonoid biosynthesis and enhancing UV-B resistance.Under low temperatures,β-glucans improve frost tolerance by modulating osmotic balance and inhibiting ice-nucleating proteins,while lipids maintain membrane fluidity to sustain cellular function during cold stress.Importantly,we explore the hypothesis that these same metabolites,upon consumption,may facilitate human adaptation to high-altitude stresses.This hypothesis is supported by preliminary epidemiological associations between Qingke consumption and favorable health outcomes in high-altitude populations,as well as established bioactivities of the implicated metabolites in vitro and in animal models.However,direct causal evidence in humans and a comprehensive understanding of the underlying molecular mechanisms remain key knowledge gaps that warrant future investigation.Qingke as a unique resource at the interface of agricultural resilience and human nutrition.Understanding its metabolic blueprint will inform the development of functional foods and climate-resilient crops. 展开更多
关键词 Qingke Metabolomics Multi-omics integration Plateau adaptation
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ADAPTIVITY IN SPACE AND TIME FOR MAGNETOQUASISTATICS 被引量:1
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作者 Markus Clemens Jens Lang +1 位作者 Delia Teleaga Georg Wimmer 《Journal of Computational Mathematics》 SCIE CSCD 2009年第5期642-656,共15页
This paper addresses fully space-time adaptive magnetic field computations. We describe an adaptive Whitney finite element method for solving the magnetoquasistatic formulation of Maxwell's equations on unstructured ... This paper addresses fully space-time adaptive magnetic field computations. We describe an adaptive Whitney finite element method for solving the magnetoquasistatic formulation of Maxwell's equations on unstructured 3D tetrahedral grids. Spatial mesh re- finement and coarsening are based on hierarchical error estimators especially designed for combining tetrahedral H(curl)-conforming edge elements in space with linearly implicit Rosenbrock methods in time. An embedding technique is applied to get efficiency in time through variable time steps. Finally, we present numerical results for the magnetic recording write head benchmark problem proposed by the Storage Research Consortium in Japan. 展开更多
关键词 Magnetoquasistatics Space-time adaptivity Edge elements Rosenbrock meth-ods Hierarchical error estimator SRC benchmark problem.
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Adaptivity and A Posteriori Error Control for Bifurcation Problems Ⅰ:The Bratu Problem 被引量:1
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作者 K.Andrew Cliffe Edward J.C.Hall +2 位作者 Paul Houston Eric T.Phipps Andrew G.Salinger 《Communications in Computational Physics》 SCIE 2010年第9期845-865,共21页
This article is concerned with the numerical detection of bifurcation points of nonlinear partial differential equations as some parameter of interest is varied.In particular,we study in detail the numerical approxima... This article is concerned with the numerical detection of bifurcation points of nonlinear partial differential equations as some parameter of interest is varied.In particular,we study in detail the numerical approximation of the Bratu problem,based on exploiting the symmetric version of the interior penalty discontinuous Galerkin finite element method.A framework for a posteriori control of the discretization error in the computed critical parameter value is developed based upon the application of the dual weighted residual(DWR)approach.Numerical experiments are presented to highlight the practical performance of the proposed a posteriori error estimator. 展开更多
关键词 Bifurcation theory Bratu problem a posteriori error estimation adaptivity discontinuous Galerkin methods
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An Adaptive Cubic Regularisation Algorithm Based on Affine Scaling Methods for Constrained Optimization
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作者 PEI Yonggang WANG Jingyi 《应用数学》 北大核心 2026年第1期258-277,共20页
In this paper,an adaptive cubic regularisation algorithm based on affine scaling methods(ARCBASM)is proposed for solving nonlinear equality constrained programming with nonnegative constraints on variables.From the op... In this paper,an adaptive cubic regularisation algorithm based on affine scaling methods(ARCBASM)is proposed for solving nonlinear equality constrained programming with nonnegative constraints on variables.From the optimality conditions of the problem,we introduce appropriate affine matrix and construct an affine scaling ARC subproblem with linearized constraints.Composite step methods and reduced Hessian methods are applied to tackle the linearized constraints.As a result,a standard unconstrained ARC subproblem is deduced and its solution can supply sufficient decrease.The fraction to the boundary rule maintains the strict feasibility(for nonnegative constraints on variables)of every iteration point.Reflection techniques are employed to prevent the iterations from approaching zero too early.Under mild assumptions,global convergence of the algorithm is analysed.Preliminary numerical results are reported. 展开更多
关键词 Constrained optimization Adaptive cubic regularisation Affine scaling Global convergence
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Evaluating farmers' strategies and socioeconomic drivers for adaptation to climate uncertainty: A case study in the Himalayan region of West Bengal,India
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作者 Sourakanti SARKAR Aishi MUKHERJEE +6 位作者 Auindrila BISWAS Subrata GORAIN Bimal BERA Anmol GIRI Malini ROY CHOUDHURY Suman DUTTA Sumanta DAS 《Regional Sustainability》 2026年第2期116-137,共22页
Climate change poses a profound threat to mountain agro-ecosystems,particularly in the Himalayan region of West Bengal,India,by disrupting precipitation patterns,increasing temperature variability,and intensifying ext... Climate change poses a profound threat to mountain agro-ecosystems,particularly in the Himalayan region of West Bengal,India,by disrupting precipitation patterns,increasing temperature variability,and intensifying extreme weather events.Despite growing evidence of climate change impacts,there remains a critical research gap in understanding how socioeconomic factors drive farmers' adaptation strategies to climate change in this vulnerable region.This study examines how farmers in the Himalayan region of West Bengal,India,perceived and responded to the growing impacts of climate change on mountain agro-ecosystems.Drawing on cross-sectional data from 370 farm households selected through multistage sampling,the research employs a combination of analytical tools,including the severity index(SI) to assess farmers' perceptions to climate change,the adaptation index(AI) to evaluate adaptive responses,the Garrett's ranking technique to prioritize constraints,and the ordered logistic regression to identify key socioeconomic drivers of adaptation.Findings reveal a high level of climate awareness among farmers,particularly regarding the increase in weather extremes(SI=74.87%),increase in temperature(SI=72.31%),and irregular rainfall patterns and highly erratic rainfall(SI=62.52%).The most commonly adopted strategies include adopting intercropping and mixed cropping systems(AI=0.613),adoption of the integrated farming system model(AI=0.600),and shift towards non-farm employment(AI=0.608),while the adoption of climate-resilient crop varieties and improved irrigation remains limited.Regression analysis highlights that education(regression coefficient=0.38),average landholding size(regression coefficient=1.21),and access to daily weather forecast information(regression coefficient=1.92) significantly promote adaptive behaviour,whereas age(regression coefficient= –0.09) and gender(regression coefficient= –0.76) are negatively associated.Institutional constraints,particularly unavailability of institutional credit,emerge as primary barriers.The study underscores the urgent need for region-specific,inclusive policy frameworks that enhance climate advisory services,support technology dissemination,and empower marginalized groups in the Himalayan region of West Bengal.By fostering informed,equitable,and resilient agricultural systems,these strategies can significantly strengthen the adaptive capacity of mountain farming communities and contribute to sustainable development under a changing climate. 展开更多
关键词 Adaptation index Severity index Climate change Adaptation strategies Garrett's ranking Himalayan region
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The biochemical and metabolic adaptations underpinning the health benefits of exercise
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作者 Robyn M.Murphy Mark A.Febbraio 《Journal of Sport and Health Science》 2026年第1期1-2,共2页
1.Introduction The field of exercise science is experiencing a renaissance,with recent research illuminating the molecular,cellular,and systemic effects of physical activity.This is largely due to the now unequivocal ... 1.Introduction The field of exercise science is experiencing a renaissance,with recent research illuminating the molecular,cellular,and systemic effects of physical activity.This is largely due to the now unequivocal evidence that a lack of physical activity,not only has direct effects on the prevalence of non-contagious diseases(NCDs)but has profound additive effects of other risk factors for NCD such as obesity and hypertension.1 The articles in this special topic of Journal of Sport and Health Science(JSHS)are dedicated to research on Exercise biochemistry&metabolism. 展开更多
关键词 OBESITY metabolic adaptations EXERCISE health benefits exercise science biochemical adaptations physical activity non contagious diseases
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Adaptation needs and adaptation options vary among different stakeholders in high-latitude protected areas: A case study of the Qiangtang Protected Area in China
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作者 Jianguo Wu Mengdi Fu 《Chinese Journal of Population,Resources and Environment》 2026年第1期110-128,共19页
It is essential to understand how adaptation needs and options differ among stakeholders in protected areas(PAs)to effectively implement climate change(CC)adaptation strategies.Using the Qiangtang PA in Xizang as a ca... It is essential to understand how adaptation needs and options differ among stakeholders in protected areas(PAs)to effectively implement climate change(CC)adaptation strategies.Using the Qiangtang PA in Xizang as a case study,this research examines CC adaptation needs and options from the perspectives of stakeholders across multiple administrative levels,including provincial,prefectural,county authorities,73 protection stations,and 13364 pastoralists residing within the PA.The findings show that stakeholders at the provincial level,as well as those from the Ali and Naqu prefectures and six counties,place greater emphasis on institutional and resource-related needs than on other categories(attention score:7.0-9.3 vs.5.0-7.0).In contrast,stakeholders from the 73 protection stations prioritize technological and capacity-building needs more strongly than other types(attention score:8.0-9.0 vs.4.0-8.0).The 13364 pastoralists assign the highest importance to social needs relative to other categories(attention score:9.0-9.5 vs.3.0-8.0).Most of the eight existing protection measures were found to indirectly support broader climate adaptation efforts.In particular,protective actions addressing fire,pests,and weather-related disasters can be classified as autonomous adaptation,while other measures generate outcomes that enhance adaptation capacity under specific conditions.Adaptation options,grouped into three main types and 13 subcategories,differ across stakeholder groups,although substantial overlap exists between these options and current protective actions,including ecosystem based adaptation strategies,adaptation-related practices,autonomous adaptation measures,and emergency interventions.Overall,these findings highlight the critical role of all stakeholders-especially staff from the 73 protection stations and the 13364 pastoralists-in the effective implementation of adaptation actions within the PA. 展开更多
关键词 Climate change Biodiversity conservation Protected area Adaptation needs Adaptation options
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Relative Motion Based Predictive Adaptive Control:A Case Study of AUV 3D Trajectory Tracking
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作者 Daxiong Ji Xinwei Wang Yuanchang Liu 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期492-494,共3页
Dear Editor,This letter deals with the autonomous underwater vehicle(AUV)three dimensional(3D)trajectory tracking control chronically suffering from poor accuracy and efficiency in complex hydrodynamics.A state-of-the... Dear Editor,This letter deals with the autonomous underwater vehicle(AUV)three dimensional(3D)trajectory tracking control chronically suffering from poor accuracy and efficiency in complex hydrodynamics.A state-of-the-art predictive adaptive controller(PAC)is proposed with a distinct dual closed-loop structure. 展开更多
关键词 adaptive controller pac autonomous underwater vehicle auv three predictive adaptive control relative motion D trajectory tracking HYDRODYNAMICS closed loop structure complex hydrodynamicsa
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Evaluating ecological resilience and enhancement strategies of the strategic hinterlands in western China
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作者 WU Chen 《Ecological Economy》 2026年第1期31-46,共16页
This study comprehensively measures the ecological resilience level of seven provinces in the strategic hinterland of Western China during 2013-2023.It constructs an ecological resilience evaluation system covering th... This study comprehensively measures the ecological resilience level of seven provinces in the strategic hinterland of Western China during 2013-2023.It constructs an ecological resilience evaluation system covering the three dimensions of"Resistance-Adaptability-Recovery"and adopts the entropy-weighted TOPSIS method for objective weighting and comprehensive ranking.The results show that:(1)The overall ecological resilience of the strategic hinterlands in Western China presents a steady upward trend,evolving from a low resilience level to a medium resilience range over the decade,with continuous investment in ecological governance and institutional supply gradually transformed into resilience enhancement effects in the long run;(2)Ecological resilience exhibits a typical pattern characterized by"high-level stability of Resistance,continuous improvement of Recovery,and relative lag of Adaptability,"among which Recovery shows the most remarkable growth rate,while Adaptability fluctuates significantly and constitutes a key bottleneck for overall leapfrog development;(3)As core carrying areas,Sichuan and Shaanxi perform outstandingly,and Guizhou demonstrates a remarkable upward momentum,while Qinghai,Ningxia,Gansu and other regions still face constraints such as limited ecological governance capacity and relatively strong structural pressures.Based on the differentiated evolutionary characteristics of the three dimensions,the study proposes enhancement paths including constructing a cross-regional ecological security barrier,breaking through the bottleneck of Adaptability,and driving high-quality resilient growth with Recovery. 展开更多
关键词 strategic hinterlands ecological resilience resistance ADAPTABILITY RECOVERY
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The effects of a supervised exercise training program during pregnancy on placental cytokines,and the potential role of fetal sex and maternal weight status
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作者 Pedro Acosta-Manzano Marta Flor-Alemany +5 位作者 Luis J.Martínez-González María Jesús Alvarez-Cubero Laura Baena-García Teresa Nestares Mireille N.M.Van Poppel Virginia A.Aparicio 《Journal of Sport and Health Science》 2026年第3期84-94,共11页
Background:The mechanisms underlying the beneficial effects of exercise on the human placenta are poorly understood.The objective of the current study was to ascertain the influence of a supervised concurrent exercise... Background:The mechanisms underlying the beneficial effects of exercise on the human placenta are poorly understood.The objective of the current study was to ascertain the influence of a supervised concurrent exercise intervention from gestational Week 17 until birth on key cytokines involved in placental development and function.Secondary aims were to explore:(a)the moderating effects of fetal sex and maternal weight status;and(b)whether gestational weight gain,lifestyle behaviors(diet,sleep patterns,and physical activity),and physical fitness(strength and cardiorespiratory fitness)mediated the effects of exercise on placental cytokines.Methods:Seventy-six pregnant women(33±4 years,mean±SD),divided into exercise(n=40)and control(n=36)groups,participated in this study.The exercise group followed a 60-min,3 days/week(aerobic+resistance)training program of moderate-to-vigorous intensity.Placental cytokines—including granulocyte-macrophage colony-stimulating factor(GM-CSF),granulocyte colony-stimulating factor(G-CSF),plateletderived growth factor AA(PDGF-AA),epidermal growth factor(EGF),monocyte chemoattractant protein-1(MCP-1),fractalkine,interleukin(IL)-8,IL-6,IL-1β,interleukin 1-receptor antagonist(IL-1ra),IL-10,tumor necrosis factor alpha(TNF-a),and interferon gamma(IFN-γ)were analyzed using Luminex multi-analyte profiling(x MAP)technology.Results:The exercise group presented higher placental levels of G-CSF and lower concentrations of EGF and IL-1ra than the control group(p<0.05).Significant effects of exercise on placental G-CSF and TNF-a(p<0.05)and a trend toward lower IL-6(p=0.08)were observed only in female placentas.Additionally,a reduction in weight gain partially mediated the effects of exercise on G-CSF(p<0.05).Conclusion:Maternal exercise during pregnancy is related to increased placental levels of G-CSF and lower EGF and IL-1ra levels.Some exercise-induced effects are observed exclusively in female placentas,including increased G-CSF and lower TNF-a and IL-6 concentrations.Notably,the increased levels of G-CSF observed with exercise might be due to a more adequate gestational weight gain. 展开更多
关键词 LIFESTYLE GESTATION Placental adaptations Sexual dimorphism Protein expression
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Whole-genome sequencing provides insights into the evolutionary adaptation and conservation of gibbons
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作者 Guiqiang Wang Yajiang Wu +8 位作者 Song Wang Ting Jia Peng Yang Zhongshi Xu Wenhui Niu Fen Shan Chen Wang Wu Chen Ting Sun 《Journal of Genetics and Genomics》 2026年第2期269-282,共14页
Gibbons are small,arboreal apes that play a critical role in tropical biodiversity and ecosystem ecology.However,nearly all species of gibbons are threatened by habitat loss,illegal trade,hunting,and other human activ... Gibbons are small,arboreal apes that play a critical role in tropical biodiversity and ecosystem ecology.However,nearly all species of gibbons are threatened by habitat loss,illegal trade,hunting,and other human activities.Long-term poor understanding of their genetics and evolution undermines effective conservation efforts.In this study,we analyse comparative population genomic data of four Nomascus species.Our results reveal strong genetic differentiation and gene flow among Nomascus species.Additionally,we identify genomic features that are potentially related to natural selection linked to vocalization,fructose metabolism,motor balance,and body size,consistent with the unique phenotype and adaptability of gibbons.Inbreeding,coupled with population declines due to climate change and historical human activities,leads to reduced genetic diversity and the accumulation of deleterious variations that likely affect cardiovascular disease and the reproductive potential of gibbons and further reduce their fitness,highlighting the urgent need for effective conservation strategies. 展开更多
关键词 GIBBONS Genetic diversity Population history Adaptive evolution CONSERVATION
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GcH1 contributes to high-altitude adaptation in Tibetans by regulating blood nitric oxide
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作者 Yongbo Guo Wangshan Zheng +6 位作者 Tian Yue Baimakangzhuo Xuebin Qi Kai Liu Liya Li Yaoxi He Bing Su 《Journal of Genetics and Genomics》 2026年第1期97-109,共13页
Nitric oxide(NO)is a key vasodilator that regulates vascular pressure and blood flow.Tibetans have developed a"blunted"mechanism for regulating NO levels at high altitude,with GTP cyclohydrolase 1(GCH1)ident... Nitric oxide(NO)is a key vasodilator that regulates vascular pressure and blood flow.Tibetans have developed a"blunted"mechanism for regulating NO levels at high altitude,with GTP cyclohydrolase 1(GCH1)identified as a key candidate gene.Here,we present comprehensive genetic and functional analyses of GCH1,which exhibits strong Darwinian positive selection in Tibetans.We show that Tibetan-enriched GCH1 variants down-regulate its expression in the blood of Tibetans.Based on this observation,we generate the heterozygous Gch1 knockout(Gch1^(+/-))mouse model to simulate its downregulation in Tibetans.We find that under prolonged hypoxia,the Gch1^(+/-)mice have relatively higher blood NO and blood oxygen saturation levels compared with the wild-type(WT)controls,providing better oxygen supplies to the cardiovascular and pulmonary systems.Markedly,hypoxia-induced cardiac hypertrophy and pulmonary remodeling are significantly attenuated in the Gch1^(^(+/-))mice compared with the WT controls,likely due to the adaptive changes in molecular regulations related to metabolism,inflammation,circadian rhythm,extracellular matrix,and oxidative stress.This study sheds light on the role of GCH1 in regulating blood NO,contributing to the physiological adaptation of the cardiovascular and pulmonary systems in Tibetans at high altitude. 展开更多
关键词 GCH1 Nitric oxide Tibetans High altitude HYPOXIA ADAPTATION
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Association between Positive Solitude and Psychological Adaptation of International Students in China:The Intermediary Roles of Authenticity and Loneliness
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作者 Hong Zou Hanwei Wu +2 位作者 Haidi Wu Ningyao Yu Zhiguang Fan 《International Journal of Mental Health Promotion》 2026年第3期163-182,共20页
Objective:International students frequently face psychological adaptation difficulties while studying and living abroad.As an effective psychological resource,positive solitude has been identified as a potential facto... Objective:International students frequently face psychological adaptation difficulties while studying and living abroad.As an effective psychological resource,positive solitude has been identified as a potential factor for improving psychological well-being,but the underlying mechanism linking the two has not been fully explored.The current study aims to explore the relationship between positive solitude and psychological adaptation of international students,with particular emphasis on the intermediary roles of authenticity and loneliness.Methods:A total of 529 international tertiary students(Mage=23.76,SD=5.08;60.68%male)were surveyed using the Positive Solitude Scale(PSS),Authenticity Scale(AS),6-item UCLA Loneliness Scale(ULS-6),and Brief Psychological Adaptation Scale(BPAS).SPSS27.0 was used for descriptive statistical analysis and Pearson correlation analysis.PROCESS macro(Model 6)was employed to test a serial mediation model,in which authenticity and loneliness function as intermediary variables between positive solitude and psychological adaptation.Results:The correlation analysis indicated significant associations among positive solitude,authenticity,loneliness,and psychological adaptation(r=−0.544~0.511).Positive solitude was directly and positively related to psychological adaptation(β=0.132,t=3.609,p<0.001)and indirectly related to psychological adaptation through two pathways:a single mediation via authenticity(indirect effect=0.089)and a serial mediation through authenticity and loneliness(indirect effect=0.062).Loneliness did not serve as a significant mediator(indirect effect=–0.015,95%CI[–0.049,0.019]).The total indirect effect was 0.136.Conclusions:Interventions targeting international students’capacity for experiencing positive solitude and authenticity can help to reduce loneliness and increase psychological adaptation.The findings derived from this study are conducive to understanding the relationship between positive solitude and psychological adaptation,as well as its underlying mechanisms.In addition,the study offers a new perspective for educational management and psychological counseling services for international students. 展开更多
关键词 International students positive solitude AUTHENTICITY psychological adaptation LONELINESS
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