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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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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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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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海量层次信息的Focus+Context交互式可视化技术 被引量:7
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作者 任磊 王威信 +3 位作者 滕东兴 马翠霞 戴国忠 王宏安 《软件学报》 EI CSCD 北大核心 2008年第11期3073-3082,共10页
综述了海量层次信息可视化与Focus+Context技术的相关工作,针对海量层次信息可视化的交互问题,在嵌套圆可视化技术的基础上提出了基于上下文感知的Focus+Context交互式可视化技术.首先,基于外切圆排列方法提出对圆心进行三角网格剖分的... 综述了海量层次信息可视化与Focus+Context技术的相关工作,针对海量层次信息可视化的交互问题,在嵌套圆可视化技术的基础上提出了基于上下文感知的Focus+Context交互式可视化技术.首先,基于外切圆排列方法提出对圆心进行三角网格剖分的方法,为变形计算建立上下文;然后,针对变形计算前后上下文一致性问题,在三角网格邻居跟踪方法的基础上,提出了用于同层兄弟节点上下文感知的外切圆变形排列方法,以及用于父子节点上下文感知的嵌套圆迭代排列方法.实验结果表明。上述方法在实现焦点突出的鱼眼视图的同时,能够有效地解决Focus+Context交互式可视化的上下文感知问题.上述方法应用于文件系统海量层次信息的交互式可视化问题,提供了交互式可视化工具. 展开更多
关键词 人机交互 用户界面 信息可视化 Focus+context 三角网格 上下文感知 文件系统
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基于Context模型的Shearlet变换地面微地震随机噪声压制 被引量:5
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作者 李月 邵丹 +1 位作者 张超 马海涛 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2018年第12期4997-5006,共10页
地面微地震监测采集到的微地震信号通常能量微弱,信噪比低,如何提高微震数据的信噪比是数据处理的难题.Shearlet变换是一种新型的多尺度几何分析方法,具有敏感的方向性和较强的稀疏表示特性,能起到很好的随机噪声压制效果.由于地面微震... 地面微地震监测采集到的微地震信号通常能量微弱,信噪比低,如何提高微震数据的信噪比是数据处理的难题.Shearlet变换是一种新型的多尺度几何分析方法,具有敏感的方向性和较强的稀疏表示特性,能起到很好的随机噪声压制效果.由于地面微震数据的有效信号大多被淹没在噪声中,基于传统阈值的Shearlet变换(the traditional threshold-based Shearlet transform TST)只考虑到尺度或方向的阈值,在去噪过程中会过度扼制有效信号系数,造成有效信号能量损失.因而,本文建立Context模型,得到基于Context模型的Shearlet变换(the Context-model-based Shearlet transform CMST)方法,改进传统Shearlet阈值方法的不足.我们通过所建立的Context模型将能量相近的各方向系数划分为同一组,并分组估计阈值,分别处理各部分系数,达到微弱同相轴有效恢复的目的.通过TST及CMST的模拟实验与实际地面微震记录处理结果对比可知,本文方法在低信噪比条件下比对比方法更加有效地恢复地面微震数据的微弱信号,随机噪声压制效果明显,在-10dB条件下,提升信噪比18.3741dB. 展开更多
关键词 地面微地震监测 随机噪声 SHEARLET变换 context模型
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基于context模型的contourlet域图像去噪 被引量:5
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作者 刘镇弢 李涛 +1 位作者 杜慧敏 韩俊刚 《计算机科学》 CSCD 北大核心 2012年第3期243-245,共3页
在分析contourlet域系数分布特征的基础上提出了一种基于context模型的contourlet域图像去噪算法。算法的关键点在于:基于contourlet变换系数的分布特性,确定合适的去噪门限;利用context模型建立图像contourlet变换后的系数分类模型并... 在分析contourlet域系数分布特征的基础上提出了一种基于context模型的contourlet域图像去噪算法。算法的关键点在于:基于contourlet变换系数的分布特性,确定合适的去噪门限;利用context模型建立图像contourlet变换后的系数分类模型并根据分类使用不同的门限去噪。实验表明,本方法能较好地去除图像噪声,在提高去噪图像PSNR值和改善主观视觉效果方面都表现出了良好的性能。 展开更多
关键词 CONTOURLET变换 图像去噪 context模型
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基于Context模型的小波变换阈值自适应图像去噪 被引量:4
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作者 薛乃玉 王玉德 赵焕利 《计算机工程与应用》 CSCD 2013年第4期227-230,共4页
根据噪声和信号的小波系数在不同分解尺度、不同方向上高频系数的分布不同,结合Context模型,提出基于Context模型的小波变换阈值自适应图像去噪算法。该算法通过对不同尺度和方向的小波分解系数应用不同的阈值方法进行去噪。实验表明,... 根据噪声和信号的小波系数在不同分解尺度、不同方向上高频系数的分布不同,结合Context模型,提出基于Context模型的小波变换阈值自适应图像去噪算法。该算法通过对不同尺度和方向的小波分解系数应用不同的阈值方法进行去噪。实验表明,方法能较好地去除图像噪声和保留图像边缘细节信息,在提高去噪图像信噪比值和改善视觉效果方面都表现出了良好的性能。 展开更多
关键词 图像去噪 context模型 小波变换 自适应
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具有一对零同态的Morita Context环(Ⅰ) 被引量:14
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作者 王尧 任艳丽 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2006年第3期318-324,共7页
设(A,B,V,W,ψ,)是一个MoritaContext,且ψ与均为零同态,C=AVWB是相应的MoritaContext环.用经典环论方法,得到了C与A,B之间的一些性质关系,同时推广了形式三角矩阵环的一些结果.
关键词 MORITA context 正则环 广义Hopf环 CLEAN环 满足m-折稳定秩条件的环
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基于小波和Context模型的海面红外弱小目标检测 被引量:5
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作者 孙国栋 吉书鹏 周桢 《红外技术》 CSCD 北大核心 2010年第2期97-100,共4页
红外图像中弱小目标的检测一直是图像处理领域的热点和难点。介绍了一种基于小波变换和Context模型空间自适应滤波的红外弱小目标检测算法。该方法首先利用小波滤波器抑制大部分背景杂波,然后采用基于Context模型的空间自适应滤波器对... 红外图像中弱小目标的检测一直是图像处理领域的热点和难点。介绍了一种基于小波变换和Context模型空间自适应滤波的红外弱小目标检测算法。该方法首先利用小波滤波器抑制大部分背景杂波,然后采用基于Context模型的空间自适应滤波器对高频系数做进一步处理,提高信噪比,最后采用基于Bayes分类算法的迭代门限进行图像分割。实验结果表明,与高通滤波相比,该方法能够更有效地检测出弱小目标。 展开更多
关键词 小波变换 context模型 红外弱小目标检测 自适应滤波
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Morita context环的根 被引量:3
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作者 王尧 任艳丽 《数学进展》 CSCD 北大核心 2016年第2期195-205,共11页
对于一个Morita context环T=(_M^R_S^N),给出若干根在某些条件下的结构.
关键词 MORITA context
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基于描述长度的Context建模算法 被引量:2
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作者 陈建华 王勇 张鸿 《电子与信息学报》 EI CSCD 北大核心 2016年第3期661-667,共7页
在基于Context建模的熵编码系统中,为了达到预期的压缩性能,需要通过Context量化来缓解由高阶Context模型所引入的"Context稀释"问题。为此,该文提出一种通过最小化描述长度来实现Context量化(Minimum Description Length Con... 在基于Context建模的熵编码系统中,为了达到预期的压缩性能,需要通过Context量化来缓解由高阶Context模型所引入的"Context稀释"问题。为此,该文提出一种通过最小化描述长度来实现Context量化(Minimum Description Length Context Quantization,MDLCQ)的算法。该算法使用描述长度作为评价准则,通过动态规划算法来实现单条件的最优Context量化,然后通过循环迭代来实现多条件的Context量化。该算法不仅可以得到多值信源的优化Context量化器,而且可以自适应地确定各个条件的重要性从而确定模型的最佳阶数。实验结果表明:由MDLCQ算法所得到的Context量化器,可以明显改善熵编码系统的压缩性能。 展开更多
关键词 条件熵编码 context量化 描述长度 算术编码
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基于提升小波和Context模型的图象无失真编码方案 被引量:2
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作者 余锦华 陈建华 施心陵 《计算机工程与应用》 CSCD 北大核心 2004年第15期49-51,118,共4页
文章讨论了提升小波变换的基本原理。并根据提升小波系数的特点,结合基于Context模型的熵编码,提出了一种新的无失真图象编码方案。该方案中,将提升小波系数的编码分为三部分考虑,即反映非零系数位置的SignificanceMap、反映非零系数幅... 文章讨论了提升小波变换的基本原理。并根据提升小波系数的特点,结合基于Context模型的熵编码,提出了一种新的无失真图象编码方案。该方案中,将提升小波系数的编码分为三部分考虑,即反映非零系数位置的SignificanceMap、反映非零系数幅值大小的MostSignificanceBits(MSB)符号流和去除了MSB的剩余二进制符号流。因为Signifi-canceMap和MSB符号流中存在较强相关性,提出了简单有效的Context模型对它们进行熵编码。而对去除了MSB的剩余二进制符号流,由于其相关性较弱,直接使用自适应算术编码。经过实验对比证明了该方案在无失真图象编码中的有效性。 展开更多
关键词 提升小波变换 context 模型 熵编码 无失真压缩
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模消去的Morita Contexts 被引量:3
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作者 陈焕艮 秦厚荣 《数学年刊(A辑)》 CSCD 北大核心 2004年第1期43-52,共10页
证明了置换环上n-稳定秩条件关于Morita Context是遗传的;进一步把该结果推广到了强可分环,从而提供了新的具有模消去的置换环。
关键词 n-稳定秩条件 强可分环 MORITA context
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