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Spatial morphology optimization for reconciling urban expansion with ecological integrity based on a multi-level ecological network framework
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作者 LU Jie JIAO Sheng CHEN Xingli 《Journal of Geographical Sciences》 2026年第2期399-420,共22页
Urban spatial morphology(USM)optimization is critical to balancing biodiversity conservation and sustainable urbanization.However,previous studies predominantly focused on the socio-economic efficiency and static ecol... Urban spatial morphology(USM)optimization is critical to balancing biodiversity conservation and sustainable urbanization.However,previous studies predominantly focused on the socio-economic efficiency and static ecological metrics and rarely addressed the dynamic USM optimization across spatial scales.Here,we developed a multi-level ecological network(MEN)framework to resolve the tension between urban expansion and ecological integrity.By integrating the cost-weighted distance analysis with a hierarchical network transmission mechanism,we established a cross-scale spatial optimization system,which coordinated the regional ecological corridors and local habitat patches.Comparative experiments with conventional single-scale approaches and scenario simulations using the PLUS model show that the MEN framework had superior performance in three dimensions:(1)spatial governance:the primary-level network(peri-urban natural reserves)effectively contained urban sprawl,and the secondary-level network(intra-urban green corridors)mitigated habitat fragmentation and improved the built-environment;(2)scenario robustness:the model maintained an optimal compactness-loose balance in multiple development pathways;(3)landscape metrics:patch fragmentation decreased by 18.25%,and the internal landscape richness improved by 10.66%compared to the scenario without USM optimization.The findings provide new insight to establish a hierarchical ecological optimization framework as a nature-based spatial protocol to reconcile metropolitan growth with landscape sustainability. 展开更多
关键词 urban spatial morphology ecological network multi-level coupling scenarios simulation urban expansion
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Impact toughness,crack initiation and propagation mechanism of Ti6422 alloy with multi-level lamellar microstructure
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作者 Jie Shen Zhihao Zhang Jianxin Xie 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期595-609,共15页
The influence of different solution and aging conditions on the microstructure,impact toughness,and crack initiation and propagation mechanisms of the novel α+β titanium alloy Ti6422 was systematically investigated.... The influence of different solution and aging conditions on the microstructure,impact toughness,and crack initiation and propagation mechanisms of the novel α+β titanium alloy Ti6422 was systematically investigated.By adjusting the furnace cooling time after solution treatment and the aging temperature,Ti6422 alloy samples were developed with a multi-level lamellar microstructure,in-cluding microscaleαcolonies and α_(p) lamellae,as well as nanoscale α_(s) phases.Extending the furnace cooling time after solution treatment at 920℃ for 1 h from 240 to 540 min,followed by aging at 600℃ for 6 h,increased the α_(p) lamella content,reduced the α_(s) phase content,expanded theαcolonies and α_(p) lamellae size,and improved the impact toughness from 22.7 to 53.8 J/cm^(2).Additionally,under the same solution treatment,raising the aging temperature from 500 to 700℃ resulted in a decrease in the α_(s) phase content and a growth in the thickness of the α_(p) lamella and α_(s) phase.The impact toughness increased significantly with these changes.Samples with high α_(p) lamellae content or large α_(s) phase size exhibited high crack initiation and propagation energies.Impact deformation caused severe kinking of the α_(p) lamellae in crack initiation and propagation areas,leading to a uniform and high-density kernel average misorientation(KAM)distribu-tion,enhancing plastic deformation coordination and uniformity.Moreover,the multidirectional arrangement of coarserαcolonies and α_(p) lamellae continuously deflect the crack propagation direction,inhibiting crack propagation. 展开更多
关键词 novel titanium alloy multi-level lamellar microstructure impact toughness crack initiation and propagation
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A Multi-Level Semantic Constraint Approach for Highway Tunnel Scene Twin Modeling 被引量:2
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作者 LI Yufei XIE Yakun +3 位作者 CHEN Mingzhen ZHAO Yaoji TU Jiaxing HU Ya 《Journal of Geodesy and Geoinformation Science》 2025年第2期37-56,共20页
As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods ge... As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods generally have problems such as insufficient 3D scene description capability and low dynamic update efficiency,which are difficult to meet the demand of real-time accurate management.For this reason,this paper proposes a vehicle twin modeling method for road tunnels.This approach starts from the actual management needs,and supports multi-level dynamic modeling from vehicle type,size to color by constructing a vehicle model library that can be flexibly invoked;at the same time,semantic constraint rules with geometric layout,behavioral attributes,and spatial relationships are designed to ensure that the virtual model matches with the real model with a high degree of similarity;ultimately,the prototype system is constructed and the case region is selected for the case study,and the dynamic vehicle status in the tunnel is realized by integrating real-time monitoring data with semantic constraints for precise virtual-real mapping.Finally,the prototype system is constructed and case experiments are conducted in selected case areas,which are combined with real-time monitoring data to realize dynamic updating and three-dimensional visualization of vehicle states in tunnels.The experiments show that the proposed method can run smoothly with an average rendering efficiency of 17.70 ms while guaranteeing the modeling accuracy(composite similarity of 0.867),which significantly improves the real-time and intuitive tunnel management.The research results provide reliable technical support for intelligent operation and emergency response of road tunnels,and offer new ideas for digital twin modeling of complex scenes. 展开更多
关键词 highway tunnel twin modeling multi-level semantic constraints tunnel vehicles multidimensional modeling
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Research on Multi-Level Automatic Filling Optimization Design Method for Layered Cross-Sectional Layout of Umbilical 被引量:1
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作者 YIN Xu FAN Zhi-rui +4 位作者 CAO Dong-hui LIU Yu-jie LI Meng-shu YAN Jun YANG Zhi-xun 《China Ocean Engineering》 2025年第5期891-903,共13页
The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly comple... The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly complex layout combinations.Furthermore,due to constraints in component quantity and geometry within the cross-sectional layout,filler bodies must be incorporated to maintain cross-section performance.Conventional design approaches based on manual experience suffer from inefficiency,high variability,and difficulties in quantification.This paper presents a multi-level automatic filling optimization design method for umbilical cross-sectional layouts to address these limitations.Initially,the research establishes a multi-objective optimization model that considers compactness,balance,and wear resistance of the cross-section,employing an enhanced genetic algorithm to achieve a near-optimal layout.Subsequently,the study implements an image processing-based vacancy detection technique to accurately identify cross-sectional gaps.To manage the variability and diversity of these vacant regions,the research introduces a multi-level filling method that strategically selects and places filler bodies of varying dimensions,overcoming the constraints of uniform-size fillers.Additionally,the method incorporates a hierarchical strategy that subdivides the complex cross-section into multiple layers,enabling layer-by-layer optimization and filling.This approach reduces manufac-turing equipment requirements while ensuring practical production process feasibility.The methodology is validated through a specific umbilical case study.The results demonstrate improvements in compactness,balance,and wear resistance compared with the initial cross-section,offering novel insights and valuable references for filler design in umbilical cross-sections. 展开更多
关键词 UMBILICAL cross-sectional layout multi-level filling layered layout optimization design
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An Expert Judgment-based Prediction Tool for Developmental and R eproductive Toxicity(DART)
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作者 LI Kangning ZHENG Yuting +7 位作者 Jane ROSE WU Shengde LI Bin Vatsal MEHTA Ashley MUDD George DASTON YU Yang WANG Ying 《生态毒理学报》 北大核心 2025年第2期77-91,共15页
Developmental and reproductive toxicity(DART)endpoint entails a toxicological assessment of all developmental stages and reproductive cycles of an organism.In silico tools to predict DART will provide a method to asse... Developmental and reproductive toxicity(DART)endpoint entails a toxicological assessment of all developmental stages and reproductive cycles of an organism.In silico tools to predict DART will provide a method to assess this complex toxicity endpoint and will be valuable for screening emerging pollutants as well as for m anaging new chemicals in China.Currently,there are few published DART prediction models in China,but many related research and development projects are in progress.In 2013,WU et al.published an expert rule-based DART decision tree(DT).This DT relies on known chemical structures linked to DART to forecast DART potential of a given chemical.Within this procedure,an accurate DART data interpretation is the foundation of building and expanding the DT.This paper excerpted case studies demonstrating DART data curation and interpretation of four chemicals(including 8-hydroxyquinoline,3,5,6-trichloro-2-pyridinol,thiacloprid,and imidacloprid)to expand the existing DART DT.Chemicals were first selected from the database of Solid Waste and Chemicals Management Center,Ministry of Ecology and Environment(MEESCC)in China.The structures of these 4 chemicals were analyzed and preliminarily grouped by chemists based on core structural features,functional groups,receptor binding property,metabolism,and possible mode of actions.Then,the DART conclusion was derived by collecting chemical information,searching,integrating,and interpreting DART data by the toxicologists.Finally,these chemicals were classified into either an existing category or a new category via integrating their chemical features,DART conclusions,and biological properties.The results showed that 8-hydroxyquinoline impacted estrous cyclicity,s exual organ weights,and embryonal development,and 3,5,6-trichloro-2-pyridinol caused central nervous system(CNS)malformations,which were added to an existing subcategory 8e(aromatic compounds with multi-halogen and nitro groups)of the DT.Thiacloprid caused dystocia and fetal skeletal malformation,and imidacloprid disrupted the endocrine system and male fertility.They both contain 2-chloro-5-methylpyridine substituted imidazolidine c yclic ring,which were expected to create a new category of neonicotinoids.The current work delineates a t ransparent process of curating toxicological data for the purpose of DART data interpretation.In the presence of sufficient related structures and DART data,the DT can be expanded by iteratively adding chemicals within the a pplicable domain of each category or subcategory.This DT can potentially serve as a tool for screening emerging pollutants and assessing new chemicals in China. 展开更多
关键词 developmental and reproductive toxicity decision tree prediction tool expert judgment new chemical management
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Fine Tuned Hybrid Deep Learning Model for Effective Judgment Prediction
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作者 G.Sukanya J.Priyadarshini 《Computer Modeling in Engineering & Sciences》 2025年第3期2925-2958,共34页
Advancements in Natural Language Processing and Deep Learning techniques have significantly pro-pelled the automation of Legal Judgment Prediction,achieving remarkable progress in legal research.Most of the existing r... Advancements in Natural Language Processing and Deep Learning techniques have significantly pro-pelled the automation of Legal Judgment Prediction,achieving remarkable progress in legal research.Most of the existing research works on Legal Judgment Prediction(LJP)use traditional optimization algorithms in deep learning techniques falling into local optimization.This research article focuses on using the modified Pelican Optimization method which mimics the collective behavior of Pelicans in the exploration and exploitation phase during cooperative food searching.Typically,the selection of search agents within a boundary is done randomly,which increases the time required to achieve global optimization.To address this,the proposed Chaotic Opposition Learning-based Pelican Optimization(COLPO)method incorporates the concept of Opposition-Based Learning combined with a chaotic cubic function,enabling deterministic selection of random numbers and reducing the number of iterations needed to reach global optimization.Also,the LJP approach in this work uses improved semantic similarity and entropy features to train a hybrid classifier combining Bi-GRU and Deep Maxout.The output scores are fused using improved score level fusion to boost prediction accuracy.The proposed COLPO method experiments with real-time Madras High Court criminal cases(Dataset 1)and the Supreme Court of India database(Dataset 2),and its performance is compared with nature-inspired algorithms such as Sparrow Search Algorithm(SSA),COOT,Spider Monkey Optimization(SMO),Pelican Optimization Algorithm(POA),as well as baseline classifier models and transformer neural networks.The results show that the proposed hybrid classifier with COLPO outperforms other cutting-edge LJP algorithms achieving 93.4%and 94.24%accuracy,respectively. 展开更多
关键词 Bi-GRU deep maxout semantic similarity legal judgment prediction opposition based learning pelican optimization
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Multi-relation spatiotemporal graph residual network model with multi-level feature attention:A novel approach for landslide displacement prediction
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作者 Ziqian Wang Xiangwei Fang +3 位作者 Wengang Zhang Xuanming Ding Luqi Wang Chao Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4211-4226,共16页
Accurate prediction of landslide displacement is crucial for effective early warning of landslide disasters.While most existing prediction methods focus on time-series forecasting for individual monitoring points,ther... Accurate prediction of landslide displacement is crucial for effective early warning of landslide disasters.While most existing prediction methods focus on time-series forecasting for individual monitoring points,there is limited research on the spatiotemporal characteristics of landslide deformation.This paper proposes a novel Multi-Relation Spatiotemporal Graph Residual Network with Multi-Level Feature Attention(MFA-MRSTGRN)that effectively improves the prediction performance of landslide displacement through spatiotemporal fusion.This model integrates internal seepage factors as data feature enhancements with external triggering factors,allowing for accurate capture of the complex spatiotemporal characteristics of landslide displacement and the construction of a multi-source heterogeneous dataset.The MFA-MRSTGRN model incorporates dynamic graph theory and four key modules:multilevel feature attention,temporal-residual decomposition,spatial multi-relational graph convolution,and spatiotemporal fusion prediction.This comprehensive approach enables the efficient analyses of multi-source heterogeneous datasets,facilitating adaptive exploration of the evolving multi-relational,multi-dimensional spatiotemporal complexities in landslides.When applying this model to predict the displacement of the Liangshuijing landslide,we demonstrate that the MFA-MRSTGRN model surpasses traditional models,such as random forest(RF),long short-term memory(LSTM),and spatial temporal graph convolutional networks(ST-GCN)models in terms of various evaluation metrics including mean absolute error(MAE=1.27 mm),root mean square error(RMSE=1.49 mm),mean absolute percentage error(MAPE=0.026),and R-squared(R^(2)=0.88).Furthermore,feature ablation experiments indicate that incorporating internal seepage factors improves the predictive performance of landslide displacement models.This research provides an advanced and reliable method for landslide displacement prediction. 展开更多
关键词 Landslide displacement prediction Spatiotemporal fusion Dynamic graph Data feature enhancement multi-level feature attention
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Multi-level distribution alignment-based domain adaptation for segmentation of 3D neuronal soma images
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作者 Li Ma Xuantai Xu Xiaoquan Yang 《Journal of Innovative Optical Health Sciences》 2025年第6期69-85,共17页
Deep learning networks are increasingly exploited in the field of neuronal soma segmentation.However,annotating dataset is also an expensive and time-consuming task.Unsupervised domain adaptation is an effective metho... Deep learning networks are increasingly exploited in the field of neuronal soma segmentation.However,annotating dataset is also an expensive and time-consuming task.Unsupervised domain adaptation is an effective method to mitigate the problem,which is able to learn an adaptive segmentation model by transferring knowledge from a rich-labeled source domain.In this paper,we propose a multi-level distribution alignment-based unsupervised domain adaptation network(MDA-Net)for segmentation of 3D neuronal soma images.Distribution alignment is performed in both feature space and output space.In the feature space,features from different scales are adaptively fused to enhance the feature extraction capability for small target somata and con-strained to be domain invariant by adversarial adaptation strategy.In the output space,local discrepancy maps that can reveal the spatial structures of somata are constructed on the predicted segmentation results.Then thedistribution alignment is performed on the local discrepancies maps across domains to obtain a superior discrepancy map in the target domain,achieving refined segmentation performance of neuronal somata.Additionally,after a period of distribution align-ment procedure,a portion of target samples with high confident pseudo-labels are selected as training data,which assist in learning a more adaptive segmentation network.We verified the superiority of the proposed algorithm by comparing several domain adaptation networks on two 3D mouse brain neuronal somata datasets and one macaque brain neuronal soma dataset. 展开更多
关键词 Unsupervised domain adaptation multi-level distribution alignment pseudo-labels 3D neuronal soma images
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A robust method for large-scale route optimization on lunar surface utilizing a multi-level map model
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作者 Yutong JIA Shengnan ZHANG +5 位作者 Bin LIU Kaichang DI Bin XIE Jing NAN Chenxu ZHAO Gang WAN 《Chinese Journal of Aeronautics》 2025年第3期134-150,共17页
As we look ahead to future lunar exploration missions, such as crewed lunar exploration and establishing lunar scientific research stations, the lunar rovers will need to cover vast distances. These distances could ra... As we look ahead to future lunar exploration missions, such as crewed lunar exploration and establishing lunar scientific research stations, the lunar rovers will need to cover vast distances. These distances could range from kilometers to tens of kilometers, and even hundreds and thousands of kilometers. Therefore, it is crucial to develop effective long-range path planning for lunar rovers to meet the demands of lunar patrol exploration. This paper presents a hierarchical map model path planning method that utilizes the existing high-resolution images, digital elevation models and mineral abundance maps. The objective is to address the issue of the construction of lunar rover travel costs in the absence of large-scale, high-resolution digital elevation models. This method models the reference and semantic layers using the middle- and low-resolution remote sensing data. The multi-scale obstacles on the lunar surface are extracted by combining the deep learning algorithm on the high-resolution image, and the obstacle avoidance layer is modeled. A two-stage exploratory path planning decision is employed for long-distance driving path planning on a global–local scale. The proposed method analyzes the long-distance accessibility of various areas of scientific significance, such as Rima Bode. A high-precision digital elevation model is created using stereo images to validate the method. Based on the findings, it can be observed that the entire route spans a distance of 930.32 km. The route demonstrates an impressive ability to avoid meter-level impact craters and linear structures while maintaining an average slope of less than 8°. This paper explores scientific research by traversing at least seven basalt units, uncovering the secrets of lunar volcanic activities, and establishing ‘golden spike’ reference points for lunar stratigraphy. The final result of path planning can serve as a valuable reference for the design, mission demonstration, and subsequent project implementation of the new manned lunar rover. 展开更多
关键词 Crewed lunar exploration Long-range path planningi multi-level map Deep learning Volcanic activities
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MLRT-UNet:An Efficient Multi-Level Relation Transformer Based U-Net for Thyroid Nodule Segmentation
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作者 Kaku Haribabu Prasath R Praveen Joe IR 《Computer Modeling in Engineering & Sciences》 2025年第4期413-448,共36页
Thyroid nodules,a common disorder in the endocrine system,require accurate segmentation in ultrasound images for effective diagnosis and treatment.However,achieving precise segmentation remains a challenge due to vari... Thyroid nodules,a common disorder in the endocrine system,require accurate segmentation in ultrasound images for effective diagnosis and treatment.However,achieving precise segmentation remains a challenge due to various factors,including scattering noise,low contrast,and limited resolution in ultrasound images.Although existing segmentation models have made progress,they still suffer from several limitations,such as high error rates,low generalizability,overfitting,limited feature learning capability,etc.To address these challenges,this paper proposes a Multi-level Relation Transformer-based U-Net(MLRT-UNet)to improve thyroid nodule segmentation.The MLRTUNet leverages a novel Relation Transformer,which processes images at multiple scales,overcoming the limitations of traditional encoding methods.This transformer integrates both local and global features effectively through selfattention and cross-attention units,capturing intricate relationships within the data.The approach also introduces a Co-operative Transformer Fusion(CTF)module to combine multi-scale features from different encoding layers,enhancing the model’s ability to capture complex patterns in the data.Furthermore,the Relation Transformer block enhances long-distance dependencies during the decoding process,improving segmentation accuracy.Experimental results showthat the MLRT-UNet achieves high segmentation accuracy,reaching 98.2% on the Digital Database Thyroid Image(DDT)dataset,97.8% on the Thyroid Nodule 3493(TG3K)dataset,and 98.2% on the Thyroid Nodule3K(TN3K)dataset.These findings demonstrate that the proposed method significantly enhances the accuracy of thyroid nodule segmentation,addressing the limitations of existing models. 展开更多
关键词 Thyroid nodules endocrine system multi-level relation transformer U-Net self-attention external attention co-operative transformer fusion thyroid nodules segmentation
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人工智能辅助教学的边界:高校教师的专业判断与价值坚守 被引量:1
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作者 唐江桥 戴珑珑 《黑龙江高教研究》 北大核心 2026年第1期13-18,共6页
人工智能辅助教学显著提升了教学效率和资源适配性,但是技术的工具理性与教育的价值理性之间的张力也随之凸显。从技术、伦理、教育规律等三个维度解析了人工智能辅助教学的边界。高校教师的专业判断能力是调和工具理性与价值理性张力... 人工智能辅助教学显著提升了教学效率和资源适配性,但是技术的工具理性与教育的价值理性之间的张力也随之凸显。从技术、伦理、教育规律等三个维度解析了人工智能辅助教学的边界。高校教师的专业判断能力是调和工具理性与价值理性张力的核心枢纽,它包括技术理解能力、数据辩证思维、教学重构能力、伦理预见能力。专业判断能力可通过技术培训、实践共同体、制度保障协同提升。高校教师的价值坚守是抵御技术异化的精神堡垒。教师应坚守以人为本的核心理念、立德树人的教育使命、促进公平的教育实践、人文关怀的情感连接等核心价值。价值坚守应在教学内容设计、教学方法创新、教师示范、制度建设等环节践行。 展开更多
关键词 人工智能辅助教学 高校教师 专业判断 价值坚守
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康德器乐美学要旨论析——基于对达尔豪斯“两个判断”的批判
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作者 王文卓 《南京艺术学院学报(音乐与表演版)》 北大核心 2026年第2期76-80,I0003,共6页
达尔豪斯提出,应从趣味判断和艺术判断两个相区别的层面去理解康德的器乐美学。本文认为,这一路径有理论局限。将“两个判断”引入批判哲学的整体语境加以分析,可成为我们把握康德器乐美学要旨的较佳路径。鉴赏判断是先天综合判断,康德... 达尔豪斯提出,应从趣味判断和艺术判断两个相区别的层面去理解康德的器乐美学。本文认为,这一路径有理论局限。将“两个判断”引入批判哲学的整体语境加以分析,可成为我们把握康德器乐美学要旨的较佳路径。鉴赏判断是先天综合判断,康德必然将一种先验的纯粹鉴赏力与经验质料综合起来,而当他把无标题幻想曲作为自由美的典型时,这个选择本身却含有了他的否定性内涵。纯粹器乐鉴赏立足于自由美取向,应用性器乐鉴赏立足于依附美取向。无论何种取向,其本质都是想象力与知性的自由游戏。“人是目的”是康德美学的最高设定,内在合目的性即着眼于这一最终目标。器乐鉴赏中的无目的性指向主体对乐音形式的鉴赏,而合目的性则指向藉乐音体验领悟人之自由本体。揭示器乐鉴赏的道德形而上学意涵,是我们充分理解康德器乐美学的重要一环。 展开更多
关键词 康德器乐美学 两个判断 先天综合判断 知性 合目的性
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改进熵权和灰关联模型的装备能力评估
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作者 王博 周文雅 +2 位作者 柯肇捷 宗飞 刘君 《系统工程与电子技术》 北大核心 2026年第2期524-534,共11页
针对传统信息熵法和灰关联模型对装备试验数据量和质量的要求过高、难以保证装备性能准确评估的问题,提出一种改进的熵权法和灰关联模型。该方法采用Bayes Bootstrap方法对小样本试验数据进行参数估计,计算出装备指标参数的点估计值,并... 针对传统信息熵法和灰关联模型对装备试验数据量和质量的要求过高、难以保证装备性能准确评估的问题,提出一种改进的熵权法和灰关联模型。该方法采用Bayes Bootstrap方法对小样本试验数据进行参数估计,计算出装备指标参数的点估计值,并构造判断比较矩阵;利用信息熵法结合装备评估指标的参数估计值完成指标客观权重的确定;通过考察装备指标参数点估计值与正、负理想解的位置关系,求解每个装备指标点估计值的正、负关联系数并聚合得出评估结果。运用该方法对侦察卫星系统探测能力进行评估,并与传统信息熵法和灰关联模型进行对比,证明了改进熵权和灰关联模型的科学性和有效性,为其在评估方法中的运用提供参考。 展开更多
关键词 信息熵 参数估计 判断比较矩阵 理想解 灰关联
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矩形顶管顶进过程中的背土效应
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作者 刘浩 金大龙 +2 位作者 袁大军 龚子邦 刘少华 《中南大学学报(自然科学版)》 北大核心 2026年第2期708-717,共10页
针对“背土效应”问题,本文提出了一种新的背土破坏判定方法。首先,结合实际工程中的沉降监测数据,确定受背土效应影响的土体范围,并将其沿顶进方向划定为左右两侧为向上延伸的梯形区域,前缘边界为圆弧形滑裂面;然后,基于四项合理假定,... 针对“背土效应”问题,本文提出了一种新的背土破坏判定方法。首先,结合实际工程中的沉降监测数据,确定受背土效应影响的土体范围,并将其沿顶进方向划定为左右两侧为向上延伸的梯形区域,前缘边界为圆弧形滑裂面;然后,基于四项合理假定,简化背土体模型,结合矩形顶管掘进过程中的三维背土破坏力学模型,推导出破坏判定公式;第三,通过实际工程算例,开展参数敏感性分析,揭示了背土效应与顶管顶进长度、埋置深度以及土体物理力学参数之间的相互关系,给出了发生临界破坏时的摩擦因数;最后,分析了在不同地质条件下,为防止背土破坏而需满足的最小覆土厚度要求。研究结果表明:管土临界摩擦因数随管节埋深、地层黏聚力以及内摩擦角增大而增大,随顶进长度增大而减小;背土破坏中存在“临界黏聚力”,当黏聚力大于12.5 kPa时,顶管最浅埋深随顶进距离增加而减小,当黏聚力小于12.5 kPa时,则呈相反规律;无黏聚力地层中,背土体的稳定性由内摩擦角与顶进长度共同控制,且最浅埋深对顶进距离高度敏感;当顶进距离超过20 m后,最浅埋深显著增大,需通过增大覆土厚度或有效降低管土摩擦力以避免整体背土破坏。 展开更多
关键词 矩形顶管 地表隆沉 背土效应 判定方法 最浅埋深
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幼儿园教育监管责任界定的困境及其化解策略
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作者 蔡迎旗 张媛聆 《河北师范大学学报(教育科学版)》 北大核心 2026年第2期131-140,共10页
幼儿园教育监管责任的科学界定是保障儿童权益、完善幼儿园安全治理体系的首要前提。为探究幼儿园教育监管责任界定的困境及其形成机制,以489份司法判决书为样本,运用扎根理论构建幼儿园责任界定的多维影响机制模型,进而揭示当前幼儿园... 幼儿园教育监管责任的科学界定是保障儿童权益、完善幼儿园安全治理体系的首要前提。为探究幼儿园教育监管责任界定的困境及其形成机制,以489份司法判决书为样本,运用扎根理论构建幼儿园责任界定的多维影响机制模型,进而揭示当前幼儿园教育监管责任界定的内在逻辑。研究发现,幼儿园教育监管责任界定的困境既源于责任产生阶段中风险防范机制的有限性、伤害产生的复杂性及事件应对的局限性,又植根于责任界定过程中举证的证成困境、损害评估的维度差异及过错判断的价值选择,也来自于责任承担中法律适用的不确定性。建议通过强化家园协作、加强幼儿园治理能力、优化保险机制与完善法律体系等措施,化解责任界定各阶段存在的主要问题,系统提升幼儿园安全治理的法治化水平。 展开更多
关键词 幼儿园 教育监管 责任界定 裁判文书 家园协作
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环保服装价值感知对消费者购买意愿影响机制研究——基于在线品牌社群信息传递
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作者 梅蕾 王丽媛 《浙江纺织服装职业技术学院学报》 2026年第1期45-55,共11页
推进高耗能、高污染的传统纺织服装业绿色转型,可以减少行业发展所造成的环境污染,助力“双碳”目标实现。服装业绿色发展不仅仅是材料环保和工艺降碳减排,还必须依靠消费者对环保服装的认可与购买。在此背景下,基于在线品牌社群信息传... 推进高耗能、高污染的传统纺织服装业绿色转型,可以减少行业发展所造成的环境污染,助力“双碳”目标实现。服装业绿色发展不仅仅是材料环保和工艺降碳减排,还必须依靠消费者对环保服装的认可与购买。在此背景下,基于在线品牌社群信息传递,结合SOR理论、社会交换理论和感知价值理论构建模型,揭示环保服装的产品感知价值对消费者购买意愿的影响机制。研究结果表明:(1)产品感知价值的4个变量均正向影响消费者购买意愿;(2)理性判断在产品功能价值与购买意愿的路径中做部分中介,非理性判断在产品情感、社会和新奇价值与购买意愿的路径中做部分中介;(3)社区认同在产品功能、情感和新奇价值与购买意愿的直接效应链路上起调节作用,在产品社会、新奇价值与非理性判断的路径上起调节作用;社区粘性在产品情感价值与非理性判断中起调节作用。基于此,从强化信息传递的新奇价值、根据理性和非理性信息选择不同的信息传递路径以及提升网络社群的社区认同与社区黏性等方面,为企业提出提升品牌社群信息传递效率,促进消费者低碳环保消费的管理启示。 展开更多
关键词 品牌社群 环保服装 感知价值 理性判断 非理性判断
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钢中卷渣类夹杂物的示踪研究
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作者 任英 肖梦旋 +5 位作者 王博辰 张贺君 杜国利 曾垚 李永武 张立峰 《河北冶金》 2026年第1期59-63,71,共6页
大尺寸夹杂物是轧板缺陷的主要原因,其成分与精炼渣、中间包覆盖剂和结晶器保护渣成分接近。为准确判断钢中大尺寸夹杂物的来源,以典型低碳铝镇静钢为研究对象,在高品质钢生产过程进行示踪剂试验,分别在精炼渣和中间包覆盖剂中加入SrCO_... 大尺寸夹杂物是轧板缺陷的主要原因,其成分与精炼渣、中间包覆盖剂和结晶器保护渣成分接近。为准确判断钢中大尺寸夹杂物的来源,以典型低碳铝镇静钢为研究对象,在高品质钢生产过程进行示踪剂试验,分别在精炼渣和中间包覆盖剂中加入SrCO_(3)和BaCO_(3)作为示踪剂,结晶器保护渣中的K_(2)O和Na2O可以作为示踪元素。冶炼过程中,钢中T.O随着夹杂物上浮呈现出下降趋势,由43 ppm下降至23 ppm。浇铸末期随着余钢量的逐渐降低,发生卷渣和吸气,进而导致T.O逐渐上升至31 ppm。在整个生产过程中,夹杂物平均成分中的Al_(2)O_(3)含量始终大于80%,且随着冶炼的进行而逐渐增加,最终稳定在93%左右。由于夹杂物逐渐向Al_(2)O_(3)转化,连铸坯中夹杂物最大直径达到67μm。提出了示踪实验过程中根据卷渣类夹杂物渣相成分、示踪元素含量、卷渣夹杂物尺寸的判定规则,综合确定卷渣类夹杂物的来源。对连铸坯中夹杂物进行了大尺寸扫描,发现大尺寸夹杂物主要成分为CaO和Al_(2)O_(3),含有少量的SrO或K_(2)O,可以确定铸坯中的卷渣夹杂物主要来源是精炼渣和结晶器保护渣。 展开更多
关键词 高品质钢 夹杂物 渣相成分 示踪 卷渣 综合判定规则
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1938-1939年国民党高层对长沙战局的研判与因应
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作者 刘长林 胡丞嗣 《安徽史学》 北大核心 2026年第1期63-75,共13页
1938年10月,广州、武汉沦陷后,日军第11军继续追击南撤的中国军队,并营造直取长沙的假象,实则攻占岳阳后即转为警备态势。国民党高层在仓促启动保卫长沙部署的同时,也做了焚城准备,并在岳阳沦陷的恐慌中失控实施,酿成“文夕大火”惨案... 1938年10月,广州、武汉沦陷后,日军第11军继续追击南撤的中国军队,并营造直取长沙的假象,实则攻占岳阳后即转为警备态势。国民党高层在仓促启动保卫长沙部署的同时,也做了焚城准备,并在岳阳沦陷的恐慌中失控实施,酿成“文夕大火”惨案。大火过后,湘北前线形成对峙局面,日军也暂未将长沙列为攻占目标。其间,国民党高层虽由于缺乏确切情报,接连误判日军进攻长沙时间,却仍将日军“必攻长沙”作为战略预设,在第二期作战方案指导下,围绕“争取外线”与“后退决战”的战术原则,制定了诱敌深入后于长沙近郊实施反攻的作战计划,并据此逐步完成防线部署与战场准备。1939年9月,日军在遭遇国民党军春夏攻势袭扰后,先发制人在湘北寻歼第九战区“主力”,但仍无意攻占长沙,国民党军依照既定策略阻滞日军后,因长沙未失,遂将此役视为大捷。第一次长沙会战是双方战略战术碰撞下达成的阶段性平衡,但均未能在战略层面取得决定性突破,这也就为后续几次长沙会战的爆发埋下了伏笔。 展开更多
关键词 第一次长沙会战 第九战区 蒋介石 战略研判 因应
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外国法院判决承认与执行中管辖权审查的法律适用问题
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作者 孙南申 胡蓉 《国际商务研究》 北大核心 2026年第1期72-80,共9页
国际民商事争议的管辖权不仅指原审国法院审理案件争议的直接管辖权,也包括被请求国法院在判决承认执行阶段审查原审国法院是否具备合理管辖权的间接管辖权。直接管辖权的实质是原审国具有审理案件的管辖基础,间接管辖权关注的是原审国... 国际民商事争议的管辖权不仅指原审国法院审理案件争议的直接管辖权,也包括被请求国法院在判决承认执行阶段审查原审国法院是否具备合理管辖权的间接管辖权。直接管辖权的实质是原审国具有审理案件的管辖基础,间接管辖权关注的是原审国管辖权的行使是否正当与合理。间接管辖权审查的法律适用涉及两方面问题,一是确定间接管辖权的准据法,二是确定间接管辖权的审查标准,这两者相互关联。实践中对此的适用与确定模式主要包括适用被请求国法律、适用请求国法律、结合适用被请求国与请求国法律、适用司法协助条约规定等。《2019年海牙判决公约》规定的间接管辖规则体现的是管辖法院与案件及其被告之间的实质联系,并作为判断管辖基础合理性的依据与标准。针对以上背景与问题,本文从间接管辖审查的法律适用关系与功能、法律适用模式与原则、审查标准的适用、中国间接管辖审查依据与标准等4个方面进行理论与实证分析,并得出相应观点与结论。 展开更多
关键词 外国法院判决 承认与执行 间接管辖审查 法律适用 审查标准
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集资诈骗罪非法占有目的的裁判规则——基于人民法院入库案例的实证分析
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作者 刘宪权 王志亮 《浙江工商大学学报》 北大核心 2026年第1期55-64,共10页
在司法解释单项推定模式基础上,人民法院入库案例采取要素组合的方式,情境化地细化了金融诈骗罪非法占有目的的裁判规则。总结而言,这些要素主要是集资宣传、集资款去向以及资金归还能力,个案当中的要素组合方式又各不相同。学理上需要... 在司法解释单项推定模式基础上,人民法院入库案例采取要素组合的方式,情境化地细化了金融诈骗罪非法占有目的的裁判规则。总结而言,这些要素主要是集资宣传、集资款去向以及资金归还能力,个案当中的要素组合方式又各不相同。学理上需要立足于对裁判规律的总结,构筑一种分步式认定的模式。是否存在真实的生产经营以及是否将所集资金用于生产经营,是判断非法占有目的的基本要素。应当在此基础上判断集资人的还款能力,最后判断其归还意愿。非法占有目的是一种积极追求的故意,不应包括放任的故意,是一种规范性而非事实性认定。对帮助他人非法集资者的共同非法占有目的的认定,需要重点审查其所处角色、认知能力和认知程度。 展开更多
关键词 集资诈骗罪 非法占有目的 人民法院入库案例 裁判规则 故意
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