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一种基于Multi-focus+context的鱼眼显示技术 被引量:1
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作者 路强 曹书博 +1 位作者 张广会 朱相元 《系统仿真学报》 CAS CSCD 北大核心 2013年第9期2027-2032,共6页
针对Focus+context中单焦点方式在设备屏幕上只能显示一个焦点的内容细节,而不能对多处关注细节同时显示的局限性,提出一种基于Multi-focus+context技术的,根据关联内容自适应的,显示全局图形及多个焦点内容的细节的方法。焦点区域可以... 针对Focus+context中单焦点方式在设备屏幕上只能显示一个焦点的内容细节,而不能对多处关注细节同时显示的局限性,提出一种基于Multi-focus+context技术的,根据关联内容自适应的,显示全局图形及多个焦点内容的细节的方法。焦点区域可以是任意形状的几何图形,并利用鱼眼功能将这些图形区域放大,非焦点区域大小不变,从而保持屏幕中整个图形的尺寸不变。最后,将这种方法用在移动设备显示地铁地图方面。结果表明,在看清用户关注的多个换乘站细节信息的同时,也能了解到全局的拓扑。 展开更多
关键词 multi-focus+context 鱼眼技术 地铁线路布局 信息可视化
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A Blockchain-Based Efficient Verification Scheme for Context Semantic-Aware Ciphertext Retrieval
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作者 Haochen Bao Lingyun Yuan +2 位作者 Tianyu Xie Han Chen Hui Dai 《Computers, Materials & Continua》 2026年第1期550-579,共30页
In the age of big data,ensuring data privacy while enabling efficient encrypted data retrieval has become a critical challenge.Traditional searchable encryption schemes face difficulties in handling complex semantic q... In the age of big data,ensuring data privacy while enabling efficient encrypted data retrieval has become a critical challenge.Traditional searchable encryption schemes face difficulties in handling complex semantic queries.Additionally,they typically rely on honest but curious cloud servers,which introduces the risk of repudiation.Furthermore,the combined operations of search and verification increase system load,thereby reducing performance.Traditional verification mechanisms,which rely on complex hash constructions,suffer from low verification efficiency.To address these challenges,this paper proposes a blockchain-based contextual semantic-aware ciphertext retrieval scheme with efficient verification.Building on existing single and multi-keyword search methods,the scheme uses vector models to semantically train the dataset,enabling it to retain semantic information and achieve context-aware encrypted retrieval,significantly improving search accuracy.Additionally,a blockchain-based updatable master-slave chain storage model is designed,where the master chain stores encrypted keyword indexes and the slave chain stores verification information generated by zero-knowledge proofs,thus balancing system load while improving search and verification efficiency.Finally,an improved non-interactive zero-knowledge proof mechanism is introduced,reducing the computational complexity of verification and ensuring efficient validation of search results.Experimental results demonstrate that the proposed scheme offers stronger security,balanced overhead,and higher search verification efficiency. 展开更多
关键词 Searchable encryption blockchain context semantic awareness zero-knowledge proof
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GLMCNet: A Global-Local Multiscale Context Network for High-Resolution Remote Sensing Image Semantic Segmentation
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作者 Yanting Zhang Qiyue Liu +4 位作者 Chuanzhao Tian Xuewen Li Na Yang Feng Zhang Hongyue Zhang 《Computers, Materials & Continua》 2026年第1期2086-2110,共25页
High-resolution remote sensing images(HRSIs)are now an essential data source for gathering surface information due to advancements in remote sensing data capture technologies.However,their significant scale changes an... High-resolution remote sensing images(HRSIs)are now an essential data source for gathering surface information due to advancements in remote sensing data capture technologies.However,their significant scale changes and wealth of spatial details pose challenges for semantic segmentation.While convolutional neural networks(CNNs)excel at capturing local features,they are limited in modeling long-range dependencies.Conversely,transformers utilize multihead self-attention to integrate global context effectively,but this approach often incurs a high computational cost.This paper proposes a global-local multiscale context network(GLMCNet)to extract both global and local multiscale contextual information from HRSIs.A detail-enhanced filtering module(DEFM)is proposed at the end of the encoder to refine the encoder outputs further,thereby enhancing the key details extracted by the encoder and effectively suppressing redundant information.In addition,a global-local multiscale transformer block(GLMTB)is proposed in the decoding stage to enable the modeling of rich multiscale global and local information.We also design a stair fusion mechanism to transmit deep semantic information from deep to shallow layers progressively.Finally,we propose the semantic awareness enhancement module(SAEM),which further enhances the representation of multiscale semantic features through spatial attention and covariance channel attention.Extensive ablation analyses and comparative experiments were conducted to evaluate the performance of the proposed method.Specifically,our method achieved a mean Intersection over Union(mIoU)of 86.89%on the ISPRS Potsdam dataset and 84.34%on the ISPRS Vaihingen dataset,outperforming existing models such as ABCNet and BANet. 展开更多
关键词 Multiscale context attention mechanism remote sensing images semantic segmentation
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How Do People Perceive Air Quality in Different Geographic Contexts?A Case Study of Hong Kong,China
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作者 SONG Wanying KWAN Mei-Po 《Chinese Geographical Science》 2026年第1期1-18,共18页
Perception of air pollution is subjective and context-dependent.Previous studies exploring the association between measured air pollution and perceived air quality mainly focused on air pollution levels measured in th... Perception of air pollution is subjective and context-dependent.Previous studies exploring the association between measured air pollution and perceived air quality mainly focused on air pollution levels measured in the residence-based(RB)or regional context,overlooking the mobility-based(MB)context in which people are exposed to air pollution.This study measures air pollution levels in MB,RB,and regional contexts and examines their relationships with perceived air quality across different neighborhoods and gender sub-groups of Hong Kong,China to investigate how people perceive air quality.The results indicate that particulate matter 2.5(PM_(2.5))measured in RB and the regional context significantly contributes to people’s perceived air quality compared to MB PM_(2.5).Individuals in Central and Western district of Hong Kong rely on RB,regional and MB PM_(2.5) to assess air pollution.In Sham Shui Po,RB PM_(2.5) exhibits the highest influence on people’s perceived air quality,followed by regional PM_(2.5).Women’s perceived air quality is strongly related to their RB PM_(2.5) exposure,while men’s perceived air quality is associated with both RB PM_(2.5) and regional PM_(2.5) levels.We conclude that neighborhood effects and mobility levels are the two most important factors influencing the association between meas-ured air pollution and perceived air quality.We reveal that the neighborhood effect averaging problem(NEAP)influences the associ-ation between perceived air quality and measured air pollution levels in a way that differs from health outcome-related studies.Effect-ive measures are needed to improve the public’s awareness of air pollution,and scientific control should be implemented to reduce pub-lic exposure. 展开更多
关键词 perception of air pollution particulate matter 2.5(PM_(2.5)) MOBILITY residence-based(RB) mobility-based(MB) regional contexts neighborhood Hong Kong China
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Multi-focus image fusion with the all convolutional neural network 被引量:3
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作者 杜超本 高社生 《Optoelectronics Letters》 EI 2018年第1期71-75,共5页
A decision map contains complete and clear information about the image to be fused, which is crucial to various image fusion issues, especially multi-focus image fusion. However, in order to get a satisfactory image f... A decision map contains complete and clear information about the image to be fused, which is crucial to various image fusion issues, especially multi-focus image fusion. However, in order to get a satisfactory image fusion effect, getting a decision map is very necessary and usually difficult to finish. In this letter, we address this problem with convolutional neural network(CNN), aiming to get a state-of-the-art decision map. The main idea is that the max-pooling of CNN is replaced by a convolution layer, the residuals are propagated backwards by gradient descent, and the training parameters of the individual layers of the CNN are updated layer by layer. Based on this, we propose a new all CNN(ACNN)-based multi-focus image fusion method in spatial domain. We demonstrate that the decision map obtained from the ACNN is reliable and can lead to high-quality fusion results. Experimental results clearly validate that the proposed algorithm can obtain state-of-the-art fusion performance in terms of both qualitative and quantitative evaluations. 展开更多
关键词 multi-focus image fusion with the all convolutional neural network
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A New Method of Multi-Focus Image Fusion Using Laplacian Operator and Region Optimization 被引量:1
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作者 Chao Wang Rui Yuan +3 位作者 Yuqiu Sun Yuanxiang Jiang Changsheng Chen Xiangliang Lin 《Journal of Computer and Communications》 2018年第5期106-118,共13页
Considering the continuous advancement in the field of imaging sensor, a host of other new issues have emerged. A major problem is how to find focus areas more accurately for multi-focus image fusion. The multi-focus ... Considering the continuous advancement in the field of imaging sensor, a host of other new issues have emerged. A major problem is how to find focus areas more accurately for multi-focus image fusion. The multi-focus image fusion extracts the focused information from the source images to construct a global in-focus image which includes more information than any of the source images. In this paper, a novel multi-focus image fusion based on Laplacian operator and region optimization is proposed. The evaluation of image saliency based on Laplacian operator can easily distinguish the focus region and out of focus region. And the decision map obtained by Laplacian operator processing has less the residual information than other methods. For getting precise decision map, focus area and edge optimization based on regional connectivity and edge detection have been taken. Finally, the original images are fused through the decision map. Experimental results indicate that the proposed algorithm outperforms the other series of algorithms in terms of both subjective and objective evaluations. 展开更多
关键词 Image FUSION LAPLACIAN OPERATOR multi-focus REGION OPTIMIZATION
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Efficient Compressive Multi-Focus Image Fusion
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作者 Chao Yang Bin Yang 《Journal of Computer and Communications》 2014年第9期78-86,共9页
Two key points of pixel-level multi-focus image fusion are the clarity measure and the pixel coeffi- cients fusion rule. Along with different improvements on these two points, various fusion schemes have been proposed... Two key points of pixel-level multi-focus image fusion are the clarity measure and the pixel coeffi- cients fusion rule. Along with different improvements on these two points, various fusion schemes have been proposed in literatures. However, the traditional clarity measures are not designed for compressive imaging measurements which are maps of source sense with random or likely ran- dom measurements matrix. This paper presents a novel efficient multi-focus image fusion frame- work for compressive imaging sensor network. Here the clarity measure of the raw compressive measurements is not obtained from the random sampling data itself but from the selected Hada- mard coefficients which can also be acquired from compressive imaging system efficiently. Then, the compressive measurements with different images are fused by selecting fusion rule. Finally, the block-based CS which coupled with iterative projection-based reconstruction is used to re- cover the fused image. Experimental results on common used testing data demonstrate the effectiveness of the proposed method. 展开更多
关键词 CLARITY Measures COMPRESSIVE IMAGING multi-focus IMAGE FUSION
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基于Context量化和空间co-location模式的熵编码在基因组压缩中的应用
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作者 陈慧 王丽珍 《中国科技信息》 2025年第13期135-137,共3页
1背景随着大数据和云计算等信息处理技术日趋应用广泛,熵编码日益普遍,它是以信息的概率分布特性作为编码的依据,是一种无失真的信源压缩和一种无损的压缩编码。然而在实际应用中,这些条件概率分布事先并不知道,需要通过估计得到。对条... 1背景随着大数据和云计算等信息处理技术日趋应用广泛,熵编码日益普遍,它是以信息的概率分布特性作为编码的依据,是一种无失真的信源压缩和一种无损的压缩编码。然而在实际应用中,这些条件概率分布事先并不知道,需要通过估计得到。对条件概率分布进行估计的过程称为Context建模。已有一些现成的基因组序列压缩工具可供使用,但这些工具并不针对特定基因组序列。因此,基于Context建模熵编码技术的生物基因组序列研究仍具有重要的理论意义。 展开更多
关键词 context建模 空间co-location模式 熵编码 基因组压缩
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Chinese Translation of Japanese Quotation Sentences From the Perspective of Contextual Adaptation
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作者 DING Pinyue 《Sino-US English Teaching》 2025年第2期48-52,共5页
Based on the contextual adaptation perspective of Verschueren’s Adaptation Theory,this paper explores the Chinese translation strategies of Japanese quotation sentences in the Yang translation of The Courage of One f... Based on the contextual adaptation perspective of Verschueren’s Adaptation Theory,this paper explores the Chinese translation strategies of Japanese quotation sentences in the Yang translation of The Courage of One from the perspectives of communicative context and linguistic context.The study finds that the Chinese translation of Japanese quotation sentences involves various strategies,including retaining direct quotations,converting direct quotations into statements,transforming direct quotations into attributive+noun forms,and alternating between direct and indirect quotations.This research provides a new perspective for the Chinese translation of Japanese quotation sentences and offers theoretical support for translation practices in cross-cultural communication. 展开更多
关键词 contextual adaptation communicative context direct quotation
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Japanese Learners’Vowel Perception in Chinese and Japanese Language Contexts:The Role of Word Frequency
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作者 Ting Guo Rongxia Ren +1 位作者 Sa Lu Xiaoyu Tang 《Chinese Journal of Applied Linguistics》 2025年第4期548-565,639,共19页
The current study investigated how language context and word frequency influenced vowel perception of Chinese-Japanese cognates among Chinese learners of Japanese.Focusing on orthographic cognates,participants perform... The current study investigated how language context and word frequency influenced vowel perception of Chinese-Japanese cognates among Chinese learners of Japanese.Focusing on orthographic cognates,participants performed a vowel detection task on cognates,manipulating language context and target language(Chinese vs.Japanese),as well as word frequency(high vs.low).We measured reaction times,perceptual sensitivity,and response criterion.For high-frequency words,consistent language contexts facilitated faster vowel detection in both languages.However,in low-frequency conditions,participants showed higher perceptual sensitivity to Chinese targets and more conservative response criteria for Japanese targets,regardless of context.These findings revealed the complex interplay between word frequency,language dominance,and context in cross-language processing.Our study contributed to the understanding of vowel perception in languages with shared orthography but distinct phonological systems,offering insights for models of cross-language cognition and second language education.Furthermore,it highlighted the importance of considering both word frequency and language-specific features in cross-language studies. 展开更多
关键词 language context word frequency vowel perception cross-language processing cognates
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Transformation of the Teaching Mode for Higher Vocational Public Music Courses in the Context of Artificial Intelligence
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作者 Libei He 《Journal of Contemporary Educational Research》 2025年第7期286-291,共6页
In recent years,the rapid integration of artificial intelligence(AI)with various industries has led to an intelligent transformation in people’s learning and working patterns.In the field of higher vocational public ... In recent years,the rapid integration of artificial intelligence(AI)with various industries has led to an intelligent transformation in people’s learning and working patterns.In the field of higher vocational public music course teaching,AI provides intelligent teaching tools and learning platforms,while offering students timely and scientific support and companionship,enabling them to complete learning tasks more efficiently.How to explore the transformation path of teaching modes for higher vocational public music courses in the AI context has become a key consideration for frontline teachers.Based on this,this paper first analyzes the significance of teaching higher vocational public music courses in the AI context,and then proposes feasible transformation paths for teaching modes in combination with course characteristics for reference. 展开更多
关键词 AI context Higher vocational education Public music courses Teaching mode TRANSFORMATION
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FDCPNet:feature discrimination and context propagation network for 3D shape representation
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作者 Weimin SHI Yuan XIONG +2 位作者 Qianwen WANG Han JIANG Zhong ZHOU 《虚拟现实与智能硬件(中英文)》 2025年第1期83-94,共12页
Background Three-dimensional(3D)shape representation using mesh data is essential in various applications,such as virtual reality and simulation technologies.Current methods for extracting features from mesh edges or ... Background Three-dimensional(3D)shape representation using mesh data is essential in various applications,such as virtual reality and simulation technologies.Current methods for extracting features from mesh edges or faces struggle with complex 3D models because edge-based approaches miss global contexts and face-based methods overlook variations in adjacent areas,which affects the overall precision.To address these issues,we propose the Feature Discrimination and Context Propagation Network(FDCPNet),which is a novel approach that synergistically integrates local and global features in mesh datasets.Methods FDCPNet is composed of two modules:(1)the Feature Discrimination Module,which employs an attention mechanism to enhance the identification of key local features,and(2)the Context Propagation Module,which enriches key local features by integrating global contextual information,thereby facilitating a more detailed and comprehensive representation of crucial areas within the mesh model.Results Experiments on popular datasets validated the effectiveness of FDCPNet,showing an improvement in the classification accuracy over the baseline MeshNet.Furthermore,even with reduced mesh face numbers and limited training data,FDCPNet achieved promising results,demonstrating its robustness in scenarios of variable complexity. 展开更多
关键词 3D shape representation Mesh model MeshNet Feature discrimination context propagation
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Model adaptation via credible local context representation
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作者 Song Tang Wenxin Su +2 位作者 Yan Yang Lijuan Chen Mao Ye 《CAAI Transactions on Intelligence Technology》 2025年第3期638-651,共14页
Conventional model transfer techniques,requiring the labelled source data,are not applicable in the privacy-protected medical fields.For the challenging scenarios,recent source data-free domain adaptation(SFDA)has bec... Conventional model transfer techniques,requiring the labelled source data,are not applicable in the privacy-protected medical fields.For the challenging scenarios,recent source data-free domain adaptation(SFDA)has become a mainstream solution but losing focus on the inter-sample class information.This paper proposes a new Credible Local Context Representation approach for SFDA.Our main idea is to exploit the credible local context for more discriminative representation.Specifically,we enhance the source model's discrimination by information regulating.To capture the context,a discovery method is developed that performs fixed steps walking in deep space and takes the credible features in this path as the context.In the epoch-wise adaptation,deep clustering-like training is conducted with two major updates.First,the context for all target data is constructed and then the context-fused pseudo-labels providing semantic guidance are generated.Second,for each target data,a weighting fusion on its context forms the anchored neighbourhood structure;thus,the deep clustering is switched from individual-based to coarse-grained.Also,a new regularisation building is developed on the anchored neighbourhood to drive the deep coarse-grained learning.Experiments on three benchmarks indicate that the proposed method can achieve stateof-the-art results. 展开更多
关键词 credible local context deep clustering domain adaptation machine learning model transfer self-supervised learning
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Digital Context:Social Foundation and Technological Adaptation of Digital Rural Governance
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作者 Ding Bo 《Contemporary Social Sciences》 2025年第6期116-134,共19页
Digital rural governance is a micro-level governance practice within the broader framework of building a Digital China.It involves the integration of digital technology into rural governance to drive the digital trans... Digital rural governance is a micro-level governance practice within the broader framework of building a Digital China.It involves the integration of digital technology into rural governance to drive the digital transformation of rural governance.In recognition of the varied development stages of digital rural governance,the concept of“digital context”provides an analytical lens for exploring the differences in practical models of digital rural governance.By examining the contextual characteristics and differential mechanisms of digital rural governance,this paper delves into its social foundation and technological adaptation.The research finds that the context of digital rural governance primarily encompasses three dimensions:contextual foundation,contextual logic,and contextual optimization.First,the contextual foundation of digital rural governance manifests as the social basis,comprising the social structure of villages,the type of village development,and the age structure of villagers,which constitute the social stratification forms underlying digital rural governance.Second,the contextual logic of digital rural governance focuses on the adaptation of digital technology to rural governance,promoting the adaptation of digital technology to the rural governance foundation,village governance scenarios,and villagers’digital capabilities.Third,the contextual optimization of digital rural governance emphasizes integrating digital technology with both administrative and livelihood-oriented governance affairs at the village level.This approach leverages the governance value and functional potential of digital technology to streamline digital governance processes and enhance digital governance capabilities.As a developmental direction for the transformation of rural governance,digital rural governance must not only highlight the governance advantages of digital technology but also prioritize the inherent context of rural governance.It aims to enhance the effectiveness of rural governance through digital technology and advance high-quality digital village development tailored to local conditions. 展开更多
关键词 digital village development digital rural governance digital context rural governance social foundation technological adaptation
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Global Context Fusion Network for SAR Ship Detection
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作者 Boya Zhang Yong Wang 《Journal of Beijing Institute of Technology》 2025年第6期577-589,共13页
Ship detection in synthetic aperture radar(SAR)image is crucial for marine surveillance and navigation.The application of detection network based on deep learning has achieved a promising result in SAR ship detection.... Ship detection in synthetic aperture radar(SAR)image is crucial for marine surveillance and navigation.The application of detection network based on deep learning has achieved a promising result in SAR ship detection.However,the existing networks encounters challenges due to the complex backgrounds,diverse scales and irregular distribution of ship targets.To address these issues,this article proposes a detection algorithm that integrates global context of the images(GCF-Net).First,we construct a global feature extraction module in the backbone network of GCF-Net,which encodes features along different spatial directions.Then,we incorporate bi-directional feature pyramid network(BiFPN)in the neck network to fuse the multi-scale features selectively.Finally,we design a convolution and transformer mixed(CTM)detection head to obtain contextual information of targets and concentrate network attention on the most informative regions of the images.Experimental results demonstrate that the proposed method achieves more accurate detection of ship targets in SAR images. 展开更多
关键词 synthetic aperture radar(SAR) ship detection global context fusion convolutional neural network feature extraction
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CT-MFENet:Context Transformer and Multi-Scale Feature Extraction Network via Global-Local Features Fusion for Retinal Vessels Segmentation
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作者 SHAO Dangguo YANG Yuanbiao +1 位作者 MA Lei YI Sanli 《Journal of Shanghai Jiaotong university(Science)》 2025年第4期668-682,共15页
Segmentation of the retinal vessels in the fundus is crucial for diagnosing ocular diseases.Retinal vessel images often suffer from category imbalance and large scale variations.This ultimately results in incomplete v... Segmentation of the retinal vessels in the fundus is crucial for diagnosing ocular diseases.Retinal vessel images often suffer from category imbalance and large scale variations.This ultimately results in incomplete vessel segmentation and poor continuity.In this study,we propose CT-MFENet to address the aforementioned issues.First,the use of context transformer(CT)allows for the integration of contextual feature information,which helps establish the connection between pixels and solve the problem of incomplete vessel continuity.Second,multi-scale dense residual networks are used instead of traditional CNN to address the issue of inadequate local feature extraction when the model encounters vessels at multiple scales.In the decoding stage,we introduce a local-global fusion module.It enhances the localization of vascular information and reduces the semantic gap between high-and low-level features.To address the class imbalance in retinal images,we propose a hybrid loss function that enhances the segmentation ability of the model for topological structures.We conducted experiments on the publicly available DRIVE,CHASEDB1,STARE,and IOSTAR datasets.The experimental results show that our CT-MFENet performs better than most existing methods,including the baseline U-Net. 展开更多
关键词 retinal vessel segmentation context transformer(CT) multi-scale dense residual hybrid loss function global-local fusion
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Innovation and Practice of Corporate Financial Audit in the Context of Modern Education
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作者 Jue Wang Xiaoji Ma 《Journal of Contemporary Educational Research》 2025年第9期195-201,共7页
With the development of modern educational concepts and technologies,corporate financial audit is facing unprecedented challenges and opportunities.This paper first analyzes the new characteristics of corporate financ... With the development of modern educational concepts and technologies,corporate financial audit is facing unprecedented challenges and opportunities.This paper first analyzes the new characteristics of corporate financial audit in the context of modern education,including the widespread application of digital audit tools,the diversification of audit content,and the increased requirements for audit efficiency.Then,it explores the innovative practices in corporate financial audit,such as the introduction of big data analysis technology,the construction of intelligent audit platforms,and the implementation of continuous audit.The paper also conducts an in-depth study on the impact of these innovative practices on the processes,quality,and risk management of corporate financial audit.Finally,it summarizes the effectiveness of the innovation and practice of corporate financial audit in the context of modern education,and looks forward to future development trends,providing references for theoretical research and practical operations in related fields. 展开更多
关键词 Modern education context Corporate financial audit Innovative practice Big data analysis Intelligent audit Continuous audit
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A novel method for ULS-TLS forest point cloud registration based on height context descriptor
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作者 Xusong Dai Hanwen Qi +7 位作者 Xiaochen Wang Yaozhan Xu Qinghu Jiang Qingjun Zhang Xu Wang Jianchang Chen Guangzu Liu Xinlian Liang 《Forest Ecosystems》 2025年第6期1110-1126,共17页
Unmanned aerial vehicle laser scanning(ULS)and terrestrial laser scanning(TLS)systems are effective ways to capture forest structures from top and side views,respectively.The registration of TLS and ULS data is a prer... Unmanned aerial vehicle laser scanning(ULS)and terrestrial laser scanning(TLS)systems are effective ways to capture forest structures from top and side views,respectively.The registration of TLS and ULS data is a prerequisite for a comprehensive forest structure representation.Conventional registration methods based on geometric features(e.g.,points,lines,and planes)are likely to fail due to the irregular natural point distributions of forest point clouds.Currently,automatic registration methods for forest point clouds typically rely on tree attributes(such as tree position and stem diameter).However,these methods are often unsuitable for forests with diverse compositions,complex terrains,irregular tree layouts,and insufficient common trees.In this study,an automated method is proposed to register ULS and TLS forest point clouds using ground points as registration primitives,which operates independently of tree attribute extraction and is estimated to reduce processing time by over 50%.A new evaluation method for registration accuracy evaluation is proposed,where transformation parameters from each TLS scan to the ULS obtained by the proposed registration algorithm are used to derive transformation parameters between TLS scans,which are then compared to reference parameters obtained using artificial spherical targets.Conventional ULS-TLS registration evaluation methods mostly rely on the manual corresponding points selection that is subject to inherent subjective errors,or control points in both TLS and ULS data that are difficult to collect.The proposed method presents an objective and accurate solution for ULS-TLS registration accuracy evaluation that effectively eliminates these limitations.The proposed method was tested on 12 plots with diverse stem densities,tree species,and altitudes located in a mountain forest.A total of 124 TLS scans were successfully registered to ULS data.The registration accuracy was assessed using both the conventional evaluation method and the proposed new evaluation method,with average rotation errors of 2.03 and 2.06 mrad,and average translation errors of 7.63 and 6.51 cm,respectively.The registration accuracies demonstrate that the proposed algorithm effectively and accurately registers TLS to ULS point clouds. 展开更多
关键词 Unmanned aerial vehicle Light detection and ranging(LiDAR) Terrestrial laser scanning(TLS) Registration Ground points Height context descriptor
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一种面向地图综合建筑多边形化简的Transformer模型
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作者 刘鹏程 成晓强 +2 位作者 肖天元 杨敏 艾廷华 《测绘学报》 北大核心 2026年第1期124-137,共14页
针对地图综合中建筑多边形化简方法依赖人工规则、自动化程度低且难以利用已有化简成果的问题,本文提出了一种基于Transformer机制的建筑多边形化简模型。该模型首先把建筑多边形映射至一定范围的网格空间,将建筑多边形的坐标串表达为... 针对地图综合中建筑多边形化简方法依赖人工规则、自动化程度低且难以利用已有化简成果的问题,本文提出了一种基于Transformer机制的建筑多边形化简模型。该模型首先把建筑多边形映射至一定范围的网格空间,将建筑多边形的坐标串表达为网格序列,从而获取建筑多边形化简前后的Token序列,构建出建筑多边形化简样本对数据;随后采用Transformer架构建立模型,基于样本数据利用模型的掩码自注意力机制学习点序列之间的依赖关系,最终逐点生成新的简化多边形,从而实现建筑多边形的化简。在训练过程中,模型使用结构化的样本数据,设计了忽略特定索引的交叉熵损失函数以提升化简质量。试验设计包括主试验与泛化验证两部分。主试验基于洛杉矶1∶2000建筑数据集,分别采用0.2、0.3和0.5 mm 3种网格尺寸对多边形进行编码,实现了目标比例尺为1∶5000与1∶10000的化简。试验结果表明,在0.3 mm的网格尺寸下模型性能最优,验证集上的化简结果与人工标注的一致率超过92.0%,且针对北京部分区域的建筑多边形数据的泛化试验验证了模型的迁移能力;与LSTM模型的对比分析显示,在参数规模相近的条件下,LSTM模型无法形成有效收敛,并生成可用结果。本文证实了Transformer在处理空间几何序列任务中的潜力,且能够有效复用已有化简样本,为智能建筑多边形化简提供了具有工程实用价值的途径。 展开更多
关键词 地图综合 建筑多边形化简 TOKENIZATION Transformer模型 上下文工程
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大学英语四级词汇教学中的静态语境与动态语境
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作者 黄海翔 《语言与文化研究》 2026年第2期66-70,共5页
针对大学英语四级词汇教学中的静态语境和动态语境做了详细分析,分析静态语境和动态语境之定义及组成。静态语境在教学应用阶段分为词汇表记忆、例句展示、选择题训练组成,而动态语境由语言语境、情景语境和文化语境组成。它们各自的优... 针对大学英语四级词汇教学中的静态语境和动态语境做了详细分析,分析静态语境和动态语境之定义及组成。静态语境在教学应用阶段分为词汇表记忆、例句展示、选择题训练组成,而动态语境由语言语境、情景语境和文化语境组成。它们各自的优缺点和相互关联,即在初级阶段和进阶阶段如何将基础词汇的快速积累与词汇的灵活用法结合起来。 展开更多
关键词 静态语境 动态语境 语言语境 情景语境 文化语境
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