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From"Spatial Reconstruction"to"Scene Construction":Analysis on the Design Pathway of Waterfront Space in Tourism Cities from the Perspective of Scene Theory:A Case Study of the Xuan en Night Banquet Project in Enshi
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作者 Shuyi SHEN 《Meteorological and Environmental Research》 2025年第4期16-19,25,共5页
With the upgrading of tourism consumption patterns,the traditional renovation models of waterfront recreational spaces centered on landscape design can no longer meet the commercial and humanistic demands of modern cu... With the upgrading of tourism consumption patterns,the traditional renovation models of waterfront recreational spaces centered on landscape design can no longer meet the commercial and humanistic demands of modern cultural and tourism development.Based on scene theory as the analytical framework and taking the Xuan en Night Banquet Project in Enshi as a case study,this paper explores the design pathway for transforming waterfront areas in tourism cities from"spatial reconstruction"to"scene construction".The study argues that waterfront space renewal should transcend mere physical renovation.By implementing three core strategies:spatial narrative framework,ecological industry creation,and cultural empowerment,it is possible to construct integrated scenarios that blend cultural value,consumption spaces,and lifestyle elements.This approach ultimately fosters sustained vitality in waterfront areas and promotes the high-quality development of cultural and tourism industry. 展开更多
关键词 scene theory Tourism city Comforts scene construction Waterfront space
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Fusion Prototypical Network for 3D Scene Graph Prediction
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作者 Jiho Bae Bogyu Choi +1 位作者 Sumin Yeon Suwon Lee 《Computer Modeling in Engineering & Sciences》 2025年第6期2991-3003,共13页
Scene graph prediction has emerged as a critical task in computer vision,focusing on transforming complex visual scenes into structured representations by identifying objects,their attributes,and the relationships amo... Scene graph prediction has emerged as a critical task in computer vision,focusing on transforming complex visual scenes into structured representations by identifying objects,their attributes,and the relationships among them.Extending this to 3D semantic scene graph(3DSSG)prediction introduces an additional layer of complexity because it requires the processing of point-cloud data to accurately capture the spatial and volumetric characteristics of a scene.A significant challenge in 3DSSG is the long-tailed distribution of object and relationship labels,causing certain classes to be severely underrepresented and suboptimal performance in these rare categories.To address this,we proposed a fusion prototypical network(FPN),which combines the strengths of conventional neural networks for 3DSSG with a Prototypical Network.The former are known for their ability to handle complex scene graph predictions while the latter excels in few-shot learning scenarios.By leveraging this fusion,our approach enhances the overall prediction accuracy and substantially improves the handling of underrepresented labels.Through extensive experiments using the 3DSSG dataset,we demonstrated that the FPN achieves state-of-the-art performance in 3D scene graph prediction as a single model and effectively mitigates the impact of the long-tailed distribution,providing a more balanced and comprehensive understanding of complex 3D environments. 展开更多
关键词 3D scene graph prediction prototypical network 3D scene understanding
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Accreditation of Crime Scene Investigation under ISO17020:2012 Standard in Hong Kong,china
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作者 Duen-yee Luk Terence Hok-man Cheung +4 位作者 Wai-nang Cheng Wai-kit Sze Man-hung Lo Joseph Sze-wai Wong Chi-keung Li 《刑事技术》 2025年第3期314-318,共5页
Crime scene investigation(CSI)is an important link in the criminal justice system as it serves as a bridge between establishing the happenings during an incident and possibly identifying the accountable persons,provid... Crime scene investigation(CSI)is an important link in the criminal justice system as it serves as a bridge between establishing the happenings during an incident and possibly identifying the accountable persons,providing light in the dark.The International Organization for Standardization(ISO)and the International Electrotechnical Commission(IEC)collaborated to develop the ISO/IEC 17020:2012 standard to govern the quality of CSI,a branch of inspection activity.These protocols include the impartiality and competence of the crime scene investigators involved,contemporary recording of scene observations and data obtained,the correct use of resources during scene processing,forensic evidence collection and handling procedures,and the confidentiality and integrity of any scene information obtained from other parties etc.The preparatory work,the accreditation processes involved and the implementation of new quality measures to the existing quality management system in order to achieve the ISO/IE 17020:2012 accreditation at the Forensic Science Division of the Government Laboratory in Hong Kong are discussed in this paper. 展开更多
关键词 ISO/IEC 17020 crime scene investigation on-site monitoring critical findings check independent check scene of crime officer SOCO
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DKP-SLAM:A Visual SLAM for Dynamic Indoor Scenes Based on Object Detection and Region Probability
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作者 Menglin Yin Yong Qin Jiansheng Peng 《Computers, Materials & Continua》 SCIE EI 2025年第1期1329-1347,共19页
In dynamic scenarios,visual simultaneous localization and mapping(SLAM)algorithms often incorrectly incorporate dynamic points during camera pose computation,leading to reduced accuracy and robustness.This paper prese... In dynamic scenarios,visual simultaneous localization and mapping(SLAM)algorithms often incorrectly incorporate dynamic points during camera pose computation,leading to reduced accuracy and robustness.This paper presents a dynamic SLAM algorithm that leverages object detection and regional dynamic probability.Firstly,a parallel thread employs the YOLOX object detectionmodel to gather 2D semantic information and compensate for missed detections.Next,an improved K-means++clustering algorithm clusters bounding box regions,adaptively determining the threshold for extracting dynamic object contours as dynamic points change.This process divides the image into low dynamic,suspicious dynamic,and high dynamic regions.In the tracking thread,the dynamic point removal module assigns dynamic probability weights to the feature points in these regions.Combined with geometric methods,it detects and removes the dynamic points.The final evaluation on the public TUM RGB-D dataset shows that the proposed dynamic SLAM algorithm surpasses most existing SLAM algorithms,providing better pose estimation accuracy and robustness in dynamic environments. 展开更多
关键词 Visual SLAM dynamic scene YOLOX K-means++clustering dynamic probability
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ERSNet:Lightweight Attention-Guided Network for Remote Sensing Scene Image Classification
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作者 LIU Yunyu YUAN Jinpeng 《Journal of Geodesy and Geoinformation Science》 2025年第1期30-46,共17页
Remote sensing scene image classification is a prominent research area within remote sensing.Deep learningbased methods have been extensively utilized and have shown significant advancements in this field.Recent progr... Remote sensing scene image classification is a prominent research area within remote sensing.Deep learningbased methods have been extensively utilized and have shown significant advancements in this field.Recent progress in these methods primarily focuses on enhancing feature representation capabilities to improve performance.The challenge lies in the limited spatial resolution of small-sized remote sensing images,as well as image blurring and sparse data.These factors contribute to lower accuracy in current deep learning models.Additionally,deeper networks with attention-based modules require a substantial number of network parameters,leading to high computational costs and memory usage.In this article,we introduce ERSNet,a lightweight novel attention-guided network for remote sensing scene image classification.ERSNet is constructed using a deep separable convolutional network and incorporates an attention mechanism.It utilizes spatial attention,channel attention,and channel self-attention to enhance feature representation and accuracy,while also reducing computational complexity and memory usage.Experimental results indicate that,compared to existing state-of-the-art methods,ERSNet has a significantly lower parameter count of only 1.2 M and reduced Flops.It achieves the highest classification accuracy of 99.14%on the EuroSAT dataset,demonstrating its suitability for application on mobile terminal devices.Furthermore,experimental results from the UCMerced land use dataset and the Brazilian coffee scene also confirm the strong generalization ability of this method. 展开更多
关键词 deep learning remote sensing scene classification CNN
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Unsupervised Monocular Depth Estimation with Edge Enhancement for Dynamic Scenes
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作者 Peicheng Shi Yueyue Tang +3 位作者 Yi Li Xinlong Dong Yu Sun Aixi Yang 《Computers, Materials & Continua》 2025年第8期3321-3343,共23页
In the dynamic scene of autonomous vehicles,the depth estimation of monocular cameras often faces the problem of inaccurate edge depth estimation.To solve this problem,we propose an unsupervised monocular depth estima... In the dynamic scene of autonomous vehicles,the depth estimation of monocular cameras often faces the problem of inaccurate edge depth estimation.To solve this problem,we propose an unsupervised monocular depth estimation model based on edge enhancement,which is specifically aimed at the depth perception challenge in dynamic scenes.The model consists of two core networks:a deep prediction network and a motion estimation network,both of which adopt an encoder-decoder architecture.The depth prediction network is based on the U-Net structure of ResNet18,which is responsible for generating the depth map of the scene.The motion estimation network is based on the U-Net structure of Flow-Net,focusing on the motion estimation of dynamic targets.In the decoding stage of the motion estimation network,we innovatively introduce an edge-enhanced decoder,which integrates a convolutional block attention module(CBAM)in the decoding process to enhance the recognition ability of the edge features of moving objects.In addition,we also designed a strip convolution module to improve the model’s capture efficiency of discrete moving targets.To further improve the performance of the model,we propose a novel edge regularization method based on the Laplace operator,which effectively accelerates the convergence process of themodel.Experimental results on the KITTI and Cityscapes datasets show that compared with the current advanced dynamic unsupervised monocular model,the proposed model has a significant improvement in depth estimation accuracy and convergence speed.Specifically,the rootmean square error(RMSE)is reduced by 4.8%compared with the DepthMotion algorithm,while the training convergence speed is increased by 36%,which shows the superior performance of the model in the depth estimation task in dynamic scenes. 展开更多
关键词 Dynamic scenes unsupervised learning monocular depth edge enhancement
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Assessing the effect of plot size on species diversity in a mixed oriental beech forest
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作者 Narges Kardgar Ramin Rahmani +1 位作者 Habib Zare Somayeh Ghorbani 《Journal of Forestry Research》 2025年第1期209-222,共14页
Plant species diversity is one of the most widely used indicators in ecosystem management.The relation of species diversity with the size of the sample plot has not been fully determined for Oriental beech forests(Fag... Plant species diversity is one of the most widely used indicators in ecosystem management.The relation of species diversity with the size of the sample plot has not been fully determined for Oriental beech forests(Fagus orientalis Lipsky),a widespread species in the Hyrcanian region.Assessing the impacts of plot size on species diversity is fundamental for an ecosystem-based approach to forest management.This study determined the relation of species diversity and plot size by investigating species richness and abundance of both canopy and forest floor.Two hundred and fifty-six sample plots of 625 m^(2) each were layout in a grid pattern across 16 ha.Base plots(25 m×25 m)were integrated in different scales to investigate the effect of plot size on species diversity.The total included nine plots of 0.063,0.125,0.188,0.250,0.375,0.500,0.563,0.750 and 1 ha.Ten biodiversity indices were calculated.The results show that species richness in the different plot sizes was less than the actual value.The estimated value of the Simpson species diversity index was not significantly different from actual values for both canopy and forest floor diversity.The coefficient of variation of this index for the 1-ha sample plot showed the lowest amount across different plot sizes.Inverse Hill species diversity was insignificant difference across different plot sizes with an area greater than 0.500 ha.The modified Hill evenness index for the 1-ha sample size was a correct estimation of the 16-ha for both canopy and forest floor;however,the precision estimation was higher for the canopy layer.All plots greater than 0.250-ha provided an accurate estimation of the Camargo evenness index for forest floor species,but was inaccurate across different plot sizes for the canopy layer.The results indicate that the same plot size did not have the same effect across species diversity measurements.Our results show that correct estimation of species diversity measurements is related to the selection of appropriate indicators and plot size to increase the accuracy of the estimate so that the cost and time of biodiversity management may be reduced. 展开更多
关键词 Species diversity Oriental beech forest Sample plot size Richness EVENNESS
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A Communication Scene Recognition Framework Based on Deep Learning with Multi-Sensor Fusion
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作者 Feng Yufei Zhong Xiaofeng +1 位作者 Chen Xinwei Zhou Shidong 《China Communications》 2025年第4期174-201,共28页
This paper presents a comprehensive framework that enables communication scene recognition through deep learning and multi-sensor fusion.This study aims to address the challenge of current communication scene recognit... This paper presents a comprehensive framework that enables communication scene recognition through deep learning and multi-sensor fusion.This study aims to address the challenge of current communication scene recognition methods that struggle to adapt in dynamic environments,as they typically rely on post-response mechanisms that fail to detect scene changes before users experience latency.The proposed framework leverages data from multiple smartphone sensors,including acceleration sensors,gyroscopes,magnetic field sensors,and orientation sensors,to identify different communication scenes,such as walking,running,cycling,and various modes of transportation.Extensive experimental comparative analysis with existing methods on the open-source SHL-2018 dataset confirmed the superior performance of our approach in terms of F1 score and processing speed.Additionally,tests using a Microsoft Surface Pro tablet and a self-collected Beijing-2023 dataset have validated the framework's efficiency and generalization capability.The results show that our framework achieved an F1 score of 95.15%on SHL-2018and 94.6%on Beijing-2023,highlighting its robustness across different datasets and conditions.Furthermore,the levels of computational complexity and power consumption associated with the algorithm are moderate,making it suitable for deployment on mobile devices. 展开更多
关键词 communication scene recognition deep learning sensor fusion SHL smartphone-based applications
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BSDNet:Semantic Information Distillation-Based for Bilateral-Branch Real-Time Semantic Segmentation on Street Scene Image
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作者 Huan Zeng Jianxun Zhang +1 位作者 Hongji Chen Xinwei Zhu 《Computers, Materials & Continua》 2025年第11期3879-3896,共18页
Semantic segmentation in street scenes is a crucial technology for autonomous driving to analyze the surrounding environment.In street scenes,issues such as high image resolution caused by a large viewpoints and diffe... Semantic segmentation in street scenes is a crucial technology for autonomous driving to analyze the surrounding environment.In street scenes,issues such as high image resolution caused by a large viewpoints and differences in object scales lead to a decline in real-time performance and difficulties in multi-scale feature extraction.To address this,we propose a bilateral-branch real-time semantic segmentationmethod based on semantic information distillation(BSDNet)for street scene images.The BSDNet consists of a Feature Conversion Convolutional Block(FCB),a Semantic Information Distillation Module(SIDM),and a Deep Aggregation Atrous Convolution Pyramid Pooling(DASP).FCB reduces the semantic gap between the backbone and the semantic branch.SIDM extracts high-quality semantic information fromthe Transformer branch to reduce computational costs.DASP aggregates information lost in atrous convolutions,effectively capturingmulti-scale objects.Extensive experiments conducted on Cityscapes,CamVid,and ADE20K,achieving an accuracy of 81.7% Mean Intersection over Union(mIoU)at 70.6 Frames Per Second(FPS)on Cityscapes,demonstrate that our method achieves a better balance between accuracy and inference speed. 展开更多
关键词 Street scene understanding real-time semantic segmentation knowledge distillation multi-scale feature extraction
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Navigating with Spatial Intelligence:A Survey of Scene Graph-Based Object Goal Navigation
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作者 GUO Chi LI Aolin MENG Yiyue 《Wuhan University Journal of Natural Sciences》 2025年第5期405-426,共22页
Today,autonomous mobile robots are widely used in all walks of life.Autonomous navigation,as a basic capability of robots,has become a research hotspot.Classical navigation techniques,which rely on pre-built maps,stru... Today,autonomous mobile robots are widely used in all walks of life.Autonomous navigation,as a basic capability of robots,has become a research hotspot.Classical navigation techniques,which rely on pre-built maps,struggle to cope with complex and dynamic environments.With the development of artificial intelligence,learning-based navigation technology have emerged.Instead of relying on pre-built maps,the agent perceives the environment and make decisions through visual observation,enabling end-to-end navigation.A key challenge is to enhance the generalization ability of the agent in unfamiliar environments.To tackle this challenge,it is necessary to endow the agent with spatial intelligence.Spatial intelligence refers to the ability of the agent to transform visual observations into insights,in-sights into understanding,and understanding into actions.To endow the agent with spatial intelligence,relevant research uses scene graph to represent the environment.We refer to this method as scene graph-based object goal navigation.In this paper,we concentrate on scene graph,offering formal description,computational framework of object goal navigation.We provide a comprehensive summary of the meth-ods for constructing and applying scene graph.Additionally,we present experimental evidence that highlights the critical role of scene graph in improving navigation success.This paper also delineates promising research directions,all aimed at sharpening the focus on scene graph.Overall,this paper shows how scene graph endows the agent with spatial intelligence,aiming to promote the importance of scene graph in the field of intelligent navigation. 展开更多
关键词 object goal navigation scene graph spatial intelligence deep reinforcement learning
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Monocular visual estimation for autonomous aircraft landing guidance in unknown structured scenes
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作者 Zhuo ZHANG Quanrui CHEN +2 位作者 Qiufu WANG Xiaoliang SUN Qifeng YU 《Chinese Journal of Aeronautics》 2025年第9期365-382,共18页
The autonomous landing guidance of fixed-wing aircraft in unknown structured scenes presents a substantial technological challenge,particularly regarding the effectiveness of solutions for monocular visual relative po... The autonomous landing guidance of fixed-wing aircraft in unknown structured scenes presents a substantial technological challenge,particularly regarding the effectiveness of solutions for monocular visual relative pose estimation.This study proposes a novel airborne monocular visual estimation method based on structured scene features to address this challenge.First,a multitask neural network model is established for segmentation,depth estimation,and slope estimation on monocular images.And a monocular image comprehensive three-dimensional information metric is designed,encompassing length,span,flatness,and slope information.Subsequently,structured edge features are leveraged to filter candidate landing regions adaptively.By leveraging the three-dimensional information metric,the optimal landing region is accurately and efficiently identified.Finally,sparse two-dimensional key point is used to parameterize the optimal landing region for the first time and a high-precision relative pose estimation is achieved.Additional measurement information is introduced to provide the autonomous landing guidance information between the aircraft and the optimal landing region.Experimental results obtained from both synthetic and real data demonstrate the effectiveness of the proposed method in monocular pose estimation for autonomous aircraft landing guidance in unknown structured scenes. 展开更多
关键词 Automatic landing Image processing Monocular camera Pose measurement Unknown structured scene
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HybridLSTM:An Innovative Method for Road Scene Categorization Employing Hybrid Features
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作者 Sanjay P.Pande Sarika Khandelwal +4 位作者 Ganesh K.Yenurkar Rakhi D.Wajgi Vincent O.Nyangaresi Pratik R.Hajare Poonam T.Agarkar 《Computers, Materials & Continua》 2025年第9期5937-5975,共39页
Recognizing road scene context from a single image remains a critical challenge for intelligent autonomous driving systems,particularly in dynamic and unstructured environments.While recent advancements in deep learni... Recognizing road scene context from a single image remains a critical challenge for intelligent autonomous driving systems,particularly in dynamic and unstructured environments.While recent advancements in deep learning have significantly enhanced road scene classification,simultaneously achieving high accuracy,computational efficiency,and adaptability across diverse conditions continues to be difficult.To address these challenges,this study proposes HybridLSTM,a novel and efficient framework that integrates deep learning-based,object-based,and handcrafted feature extraction methods within a unified architecture.HybridLSTM is designed to classify four distinct road scene categories—crosswalk(CW),highway(HW),overpass/tunnel(OP/T),and parking(P)—by leveraging multiple publicly available datasets,including Places-365,BDD100K,LabelMe,and KITTI,thereby promoting domain generalization.The framework fuses object-level features extracted using YOLOv5 and VGG19,scene-level global representations obtained from a modified VGG19,and fine-grained texture features captured through eight handcrafted descriptors.This hybrid feature fusion enables the model to capture both semantic context and low-level visual cues,which are critical for robust scene understanding.To model spatial arrangements and latent sequential dependencies present even in static imagery,the combined features are processed through a Long Short-Term Memory(LSTM)network,allowing the extraction of discriminative patterns across heterogeneous feature spaces.Extensive experiments conducted on 2725 annotated road scene images,with an 80:20 training-to-testing split,validate the effectiveness of the proposed model.HybridLSTM achieves a classification accuracy of 96.3%,a precision of 95.8%,a recall of 96.1%,and an F1-score of 96.0%,outperforming several existing state-of-the-art methods.These results demonstrate the robustness,scalability,and generalization capability of HybridLSTM across varying environments and scene complexities.Moreover,the framework is optimized to balance classification performance with computational efficiency,making it highly suitable for real-time deployment in embedded autonomous driving systems.Future work will focus on extending the model to multi-class detection within a single frame and optimizing it further for edge-device deployments to reduce computational overhead in practical applications. 展开更多
关键词 HybridLSTM autonomous vehicles road scene classification critical requirement global features handcrafted features
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Self-Supervised Monocular Depth Estimation with Scene Dynamic Pose
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作者 Jing He Haonan Zhu +1 位作者 Chenhao Zhao Minrui Zhao 《Computers, Materials & Continua》 2025年第6期4551-4573,共23页
Self-supervised monocular depth estimation has emerged as a major research focus in recent years,primarily due to the elimination of ground-truth depth dependence.However,the prevailing architectures in this domain su... Self-supervised monocular depth estimation has emerged as a major research focus in recent years,primarily due to the elimination of ground-truth depth dependence.However,the prevailing architectures in this domain suffer from inherent limitations:existing pose network branches infer camera ego-motion exclusively under static-scene and Lambertian-surface assumptions.These assumptions are often violated in real-world scenarios due to dynamic objects,non-Lambertian reflectance,and unstructured background elements,leading to pervasive artifacts such as depth discontinuities(“holes”),structural collapse,and ambiguous reconstruction.To address these challenges,we propose a novel framework that integrates scene dynamic pose estimation into the conventional self-supervised depth network,enhancing its ability to model complex scene dynamics.Our contributions are threefold:(1)a pixel-wise dynamic pose estimation module that jointly resolves the pose transformations of moving objects and localized scene perturbations;(2)a physically-informed loss function that couples dynamic pose and depth predictions,designed to mitigate depth errors arising from high-speed distant objects and geometrically inconsistent motion profiles;(3)an efficient SE(3)transformation parameterization that streamlines network complexity and temporal pre-processing.Extensive experiments on the KITTI and NYU-V2 benchmarks show that our framework achieves state-of-the-art performance in both quantitative metrics and qualitative visual fidelity,significantly improving the robustness and generalization of monocular depth estimation under dynamic conditions. 展开更多
关键词 Monocular depth estimation self-supervised learning scene dynamic pose estimation dynamic-depth constraint pixel-wise dynamic pose
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Relationship between topographic variables and live aboveground tree biomass on a large temperate forest plot
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作者 Dawn Lemke Luben Dimov +3 位作者 Helen Czech Patience Knight William Finch Richard Condit 《Forest Ecosystems》 2025年第5期813-821,共9页
Understanding local variation in forest biomass allows for a better evaluation of broad-scale patterns and interpretation of forest ecosystems’role in carbon dynamics.This study focuses on patterns of aboveground tre... Understanding local variation in forest biomass allows for a better evaluation of broad-scale patterns and interpretation of forest ecosystems’role in carbon dynamics.This study focuses on patterns of aboveground tree biomass within a fully censused 20 ha forest plot in a temperate forest of northern Alabama,USA.We evaluated the relationship between biomass and topography using ridge and valley landforms along with digitally derived moisture and solar radiation indices.Every live woody stem over 1 cm diameter at breast height within this plot was mapped,measured,and identified to species in 2019-2022,and diameter data were used along with speciesspecific wood density to map the aboveground biomass at the scale of 20 m×20 m quadrats.The aboveground tree biomass was 211 Mg·ha^(-1).Other than small stream areas that experienced recent natural disturbances,the total stand biomass was not associated with landform or topographic indices.Dominant species,in contrast,had strong associations with topography.American beech(Fagus grandifolia)and yellow-poplar(Liriodendron tulipfera)dominated the valley landform,with 37% and 54% greater biomass in the valley than their plot average,respectively.Three other dominant species,white oak(Quercus alba),southern shagbark hickory(Carya carolinaeseptentrionalis),and white ash(Fraxinus americana),were more abundant on slopes and benches,thus partitioning the site.Of the six dominant species,only sugar maple(Acer saccharum)was not associated with landform.Moreover,both topographic wetness and potential radiation indices were significant predictors of dominant species biomass within each of the landforms.The study highlights the need to consider species when examining forest productivity in a range of site conditions. 展开更多
关键词 Aboveground tree biomass Paint rock forest dynamics plot Topographic wetness index(TWI) Potential radiation Landform position index
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Video action recognition meets vision-language models exploring human factors in scene interaction: a review
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作者 GUO Yuping GAO Hongwei +3 位作者 YU Jiahui GE Jinchao HAN Meng JU Zhaojie 《Optoelectronics Letters》 2025年第10期626-640,共15页
Video action recognition(VAR)aims to analyze dynamic behaviors in videos and achieve semantic understanding.VAR faces challenges such as temporal dynamics,action-scene coupling,and the complexity of human interactions... Video action recognition(VAR)aims to analyze dynamic behaviors in videos and achieve semantic understanding.VAR faces challenges such as temporal dynamics,action-scene coupling,and the complexity of human interactions.Existing methods can be categorized into motion-level,event-level,and story-level ones based on spatiotemporal granularity.However,single-modal approaches struggle to capture complex behavioral semantics and human factors.Therefore,in recent years,vision-language models(VLMs)have been introduced into this field,providing new research perspectives for VAR.In this paper,we systematically review spatiotemporal hierarchical methods in VAR and explore how the introduction of large models has advanced the field.Additionally,we propose the concept of“Factor”to identify and integrate key information from both visual and textual modalities,enhancing multimodal alignment.We also summarize various multimodal alignment methods and provide in-depth analysis and insights into future research directions. 展开更多
关键词 human factors video action recognition vision language models analyze dynamic behaviors spatiotemporal granularity video action recognition var aims multimodal alignment scene interaction
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利用原位连续测定水汽δ^(18)O值和Keeling Plot方法区分麦田蒸散组分 被引量:33
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作者 袁国富 张娜 +2 位作者 孙晓敏 温学发 张世春 《植物生态学报》 CAS CSCD 北大核心 2010年第2期170-178,共9页
利用稳定同位素技术和Keeling Plot方法可以有效分割地表蒸散量,进而加深对陆地生态系统水循环的理解。该研究通过原位连续测定麦田的水汽同位素数据,评价Keeling Plot方法在分割地表蒸散中的应用,并揭示华北冬小麦(Triticum aes-tivum... 利用稳定同位素技术和Keeling Plot方法可以有效分割地表蒸散量,进而加深对陆地生态系统水循环的理解。该研究通过原位连续测定麦田的水汽同位素数据,评价Keeling Plot方法在分割地表蒸散中的应用,并揭示华北冬小麦(Triticum aes-tivum)蒸腾在总蒸散中的比例。实验于2008年3-5月在中国科学院栾城农业生态站进行,利用国际上先进的H218O、HD16O激光痕量气体分析仪(TDLAS)为基础构建的大气水汽18O/16O和D/H同位素比原位连续观测系统,同时利用涡度相关技术、真空抽提技术、同位素质谱仪技术,获取了必要的数据。研究分析了一天中不同时间段的连续的大气水汽δ18O与水汽浓度倒数拟合Keeling Plot曲线的差异和可能的原因。结果显示,中午时段的拟合结果较好,这也暗示中午时段蒸腾速率高时最可能满足植物蒸腾的同位素稳定态假设。进一步的分析发现植物蒸腾的同位素稳定态并不总是成立,尤其是水分胁迫下进入成熟期的小麦,其蒸腾水汽同位素一般处于非稳定态。利用同位素分割结果显示,生长盛期麦田94%-99%的蒸散来源于植物蒸腾。 展开更多
关键词 通量分割 Keeling plot 稳定同位素 激光痕量气体分析仪(TDLAS)
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高效PLOT碳分子筛石英毛细管柱的研制及其性能研究 被引量:5
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作者 赵国宏 曾庆梅 +3 位作者 孔德玮 吴行阳 雷晓强 吕祖芳 《分析测试学报》 CAS CSCD 1999年第5期60-61,共2页
选用碳分子筛作吸附剂 ,用液相沉淀法涂渍出高效PLOT碳分子筛石英毛细管色谱柱 ,并对其色谱性能进行了考察。结果表明 ,该色谱柱具有良好的分离特性 ,1次进样可分离出O2、N2、CO、CO2、CH4、C2H2、C2H4、C2H6 等组分;适用于炼厂气、烟... 选用碳分子筛作吸附剂 ,用液相沉淀法涂渍出高效PLOT碳分子筛石英毛细管色谱柱 ,并对其色谱性能进行了考察。结果表明 ,该色谱柱具有良好的分离特性 ,1次进样可分离出O2、N2、CO、CO2、CH4、C2H2、C2H4、C2H6 等组分;适用于炼厂气、烟道气、水煤气及变压器油溶解气等的分析。 展开更多
关键词 plot 多孔层开管柱 气体分析 碳分子筛 色谱柱
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PLOT柱分离GC-MS法测定酿酒发酵产品中的微量丁二酮和苯乙烯 被引量:3
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作者 刘绍从 吕刚 +2 位作者 赵好力宝 李德泉 刘军 《分析测试学报》 CAS CSCD 北大核心 2006年第1期127-129,共3页
用PLOT柱分离,气相色谱-质谱联用对酿酒发酵产品中微量丁二酮和苯乙烯含量进行测定。GC条件为:毛细管色谱柱,HP-PLOTU,30m×0.32mm×10μm;载气(He)流速,1.5mL/min;进样口温度,200℃;柱温,180℃;分流比。50:1... 用PLOT柱分离,气相色谱-质谱联用对酿酒发酵产品中微量丁二酮和苯乙烯含量进行测定。GC条件为:毛细管色谱柱,HP-PLOTU,30m×0.32mm×10μm;载气(He)流速,1.5mL/min;进样口温度,200℃;柱温,180℃;分流比。50:1;进样量0.5μL。MS条件:电子轰击电离源能量。70eV;选择离子扫描方式;溶剂延迟。3.0min。结果表明:丁二酬和乙醇达到基线分离。在25min内一次完成对酿酒发酵产品中微量丁二酮和苯乙烯含量的分离测定。方法的检出限为0.01mg/L,相对标准偏差小于2.0%,平均加标回收率为95%~104%。 展开更多
关键词 plot 气相色谱-质谱 丁二酮 苯乙烯 酿酒发酵产品
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Al_2O_3 PLOT柱的制备与应用 被引量:3
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作者 王国俊 尤进茂 欧庆瑜 《分析化学》 SCIE EI CAS CSCD 北大核心 1989年第11期979-983,共5页
本文报道了Al_2O_3 PLOT柱的制备方法。该柱适用于C_1—C_5碳氢化合物的分析。制柱方法简单,柱的使用性能不受载气湿度影响,该柱使用一年后仍能保持良好的热稳定性和重复性,失效后可以再生。本文还列举了一些应用实例。
关键词 气相色谱 毛细管柱 plot 氧化铝
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Community Structure and Diversity Distributions of Small Mammals in Different Sample Plots in the Eastern Part of Wuling Mountains 被引量:13
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作者 刘井元 杜红 +3 位作者 田耕百 余品红 王身文 彭红 《Zoological Research》 CAS CSCD 北大核心 2008年第6期637-645,共9页
Five years' (2000-2004) continuous study has been carried out on small mammals such as rodents in seven different sample plots, at three different altitudes and in six different ecological environment types in the ... Five years' (2000-2004) continuous study has been carried out on small mammals such as rodents in seven different sample plots, at three different altitudes and in six different ecological environment types in the eastern part of the Wuling Mountains, south bank of the Three Gorges of Yangtze River in Hubei. A total of 29 297 rat clamps/times were placed and 2271 small mammals such as rodents were captured, and 26 small mammals were captured by other means. All the small mammals captured belonged to 8 families 19 genera and 24 species, of which rodentia accounted for 70.83% and insectivora 29.17%. Through analysis of the data, the results showed that: 1 ) although the species richness had a trend of increasing along different sample plots as altitude increased from south to north, quite a few species showed a wide habitat range in a vertical distribution ( 15 species were dispersed over three zones and two species over two zones) , indicating a strong adaptability of small mammals such as rOdents at lower altitudes in most areas and comparatively less vertical span of entire mountains; 2) whether in seven different sample plots or six different ecological types, Apodemus agrarius and Rattus norvegicus were dominant species below 1200m, and Anourosorex squamipes, Niviventer confucianus and Apodemus draco were dominant above altitudes of 1300m, however, in quantity they were short of identical regularity, meaning they did not increase as the altitude did, or decrease as the ecological areas changed; 3)the density in winter was obviously greater than that in spring, and the distribution showed an increasing trend along with altitude, but the density in different sample plots was short of identical regularity, showing changes in different seasons and altitude grades had an important impact on small mammals such as rodents; 4) in species diversity and evenness index, there were obvious changes between the seven different sample plots, probably caused by frequent human interference in this area. Comparatively speaking, there was less human interference at high altitudes where vegetation was rich and had a high diversity and evenness index, and the boundary effect and community stability were obvious. Most ecological types have been seriously interfered with due to excessive assart at low altitudes with singular vegetation and low diversity and evenness index and poor community stability, showing an ecosystem with poor anti-reversion. If human interference can be reduced in those communities at high altitudes with low diversity and evenness index, the biological diversity in the communities will gradually recover to similar levels of other ecological areas. 展开更多
关键词 Small mammals Community structure Species diversity Sample plots Eastern part of Wuling Mountains
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