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From a Preeminent Metaphysical Poet to a Half-orphan Poet:Mis/representation of John Donne as a Full-blown Metaphysical Poet
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作者 Eugene Ngezem 《Philosophy Study》 2025年第6期369-372,共4页
The purpose of this article is to depart from the conventional belief that John Donne,a vibrant 17th-century writer,is a full-blown metaphysical poet as widely claimed while also acknowledging the poetic ingenuity of ... The purpose of this article is to depart from the conventional belief that John Donne,a vibrant 17th-century writer,is a full-blown metaphysical poet as widely claimed while also acknowledging the poetic ingenuity of John Donne.While Donne’s poetry is rich in matter and manner,and his poems are caked in wit,intellectual superiority,and apt exploration of telling themes,dressing him fully in borrowed robes seems a stretch.Some of Donne’s poems,without a shred of doubt,contain flavors of metaphysical poetry,but the term“metaphysical”seems to be unsuitable for poems such as“A Valediction:Forbidding Mourning”. 展开更多
关键词 metaphysical metaphysics mis/representation exaggeration half-orphan full-blown half-baked ingenuity
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Multimodal Signal Processing of ECG Signals with Time-Frequency Representations for Arrhythmia Classification
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作者 Yu Zhou Jiawei Tian Kyungtae Kang 《Computer Modeling in Engineering & Sciences》 2026年第2期990-1017,共28页
Arrhythmias are a frequently occurring phenomenon in clinical practice,but how to accurately dis-tinguish subtle rhythm abnormalities remains an ongoing difficulty faced by the entire research community when conductin... Arrhythmias are a frequently occurring phenomenon in clinical practice,but how to accurately dis-tinguish subtle rhythm abnormalities remains an ongoing difficulty faced by the entire research community when conducting ECG-based studies.From a review of existing studies,two main factors appear to contribute to this problem:the uneven distribution of arrhythmia classes and the limited expressiveness of features learned by current models.To overcome these limitations,this study proposes a dual-path multimodal framework,termed DM-EHC(Dual-Path Multimodal ECG Heartbeat Classifier),for ECG-based heartbeat classification.The proposed framework links 1D ECG temporal features with 2D time–frequency features.By setting up the dual paths described above,the model can process more dimensions of feature information.The MIT-BIH arrhythmia database was selected as the baseline dataset for the experiments.Experimental results show that the proposed method outperforms single modalities and performs better for certain specific types of arrhythmias.The model achieved mean precision,recall,and F1 score of 95.14%,92.26%,and 93.65%,respectively.These results indicate that the framework is robust and has potential value in automated arrhythmia classification. 展开更多
关键词 ELECTROCARDIOGRAM arrhythmia classification MULTIMODAL time-frequency representation
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bell hooks: To Resist Misrepresentations of the Outlaw Culture
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作者 黄春燕 《海外英语》 2012年第4X期3-5,共3页
The thesis summarizes bell hooks' stand and viewpoints as expressed in her book Outlaw Culture:Resisting Representations.In this collection,hooks argues that the outlaw culture,a culture of the marginalized groups... The thesis summarizes bell hooks' stand and viewpoints as expressed in her book Outlaw Culture:Resisting Representations.In this collection,hooks argues that the outlaw culture,a culture of the marginalized groups including black people and women,is either distorted or misinterpreted by the mainstream culture which is a white supremacist patriarchal one.Therefore,she calls for a resistance against the mainstream culture's misrepresentations of the outlaw culture. 展开更多
关键词 BELL HOOKS OUTLAW CULTURE RESIST representationS t
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Reconstruction of time series with missing value using 2D representation-based denoising autoencoder 被引量:2
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作者 TAO Huamin DENG Qiuqun XIAO Shanzhu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第6期1087-1096,共10页
Time series analysis is a key technology for medical diagnosis,weather forecasting and financial prediction systems.However,missing data frequently occur during data recording,posing a great challenge to data mining t... Time series analysis is a key technology for medical diagnosis,weather forecasting and financial prediction systems.However,missing data frequently occur during data recording,posing a great challenge to data mining tasks.In this study,we propose a novel time series data representation-based denoising autoencoder(DAE)for the reconstruction of missing values.Two data representation methods,namely,recurrence plot(RP)and Gramian angular field(GAF),are used to transform the raw time series to a 2D matrix for establishing the temporal correlations between different time intervals and extracting the structural patterns from the time series.Then an improved DAE is proposed to reconstruct the missing values from the 2D representation of time series.A comprehensive comparison is conducted amongst the different representations on standard datasets.Results show that the 2D representations have a lower reconstruction error than the raw time series,and the RP representation provides the best outcome.This work provides useful insights into the better reconstruction of missing values in time series analysis to considerably improve the reliability of timevarying system. 展开更多
关键词 time series missing value 2D representation denoising autoencoder(DAE) RECONSTRUCTION
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MIS3至MIS1时期闽东沿海地区高分辨率沉积与孢粉地层对古环境变化的响应特征
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作者 王继龙 戴璐 +8 位作者 丁大林 曾剑威 吴中海 牛漫兰 王凤 彭博 武彬 张艺武 于俊杰 《海洋地质与第四纪地质》 北大核心 2025年第1期29-41,共13页
为探究气候与环境剧烈转变背景下沉积物及古植被的响应特征,在前期已有研究的基础上,本研究提供了更为详细的MIS3时期至MIS1早中期的沉积与孢粉地层数据,重建了古植被与沉积演化序列,讨论了古植被、沉积特征对气候、环境演化过程的关系... 为探究气候与环境剧烈转变背景下沉积物及古植被的响应特征,在前期已有研究的基础上,本研究提供了更为详细的MIS3时期至MIS1早中期的沉积与孢粉地层数据,重建了古植被与沉积演化序列,讨论了古植被、沉积特征对气候、环境演化过程的关系。结果显示该区段岩性以砂质粉砂、粉砂质砂为主,每个钻孔均存在4个孢粉带,指示了不同的气候环境阶段。在MIS3早期与MIS1早—中期过渡阶段,出现了海相沟鞭藻囊孢及有孔虫内衬。通过地层沉积特征、孢粉特征与全球海平面、石笋δ18O曲线对比分析,发现宁德沿海岩芯在MIS3至MIS1时期沉积环境存在明显的波动,导致不同区域存在沉积间断。孢粉特征指示的MIS3中期区域气候冷期可能受H4事件影响,H3事件在沉积特征上有所响应,表明宁德地区环境受全球气候环境变化影响,在万年尺度上受控于北半球夏季太阳辐射驱动的冰期-间冰期旋回,千年尺度也受到亚洲季风及Heinrich事件影响。 展开更多
关键词 mis3—mis1 孢粉组合 气候演化 HEINRICH事件 宁德三都澳
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MIS4/3转换期东亚夏季风增强事件的精细结构及其机制剖析
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作者 黄皓翔 陈仕涛 +3 位作者 陈公哲 杨舒 王先锋 汪永进 《热带地理》 北大核心 2025年第11期2019-2028,共10页
文章基于湖北神农架永兴洞石笋的8个高精度230 Th年龄和448个δ18 O数据,重建了距今52.45—64.44 ka时段高分辨率东亚夏季风(East Asian Summer Monsoon,EASM)演化序列,完整覆盖了Dansgaarde-Oeschger(DO)18-15事件。该记录不仅揭示深... 文章基于湖北神农架永兴洞石笋的8个高精度230 Th年龄和448个δ18 O数据,重建了距今52.45—64.44 ka时段高分辨率东亚夏季风(East Asian Summer Monsoon,EASM)演化序列,完整覆盖了Dansgaarde-Oeschger(DO)18-15事件。该记录不仅揭示深海氧同位素阶段(Marine Isotope Stage,MIS)4/3转换时期DO18的快速开始-缓慢下降变化模式,还刻画了DO17a与DO16a内部的次级振荡变化,甚至清晰记录了2个先兆性事件(precursor events,PEs):PE17和PE16。结果显示,EASM强度在DO18-15事件上与格陵兰冰心记录序列一一对应,但在先兆性事件强度响应、内部结构及转型速率上存在差异。进一步研究发现,EASM强度对于先兆性事件的较弱响应和DO16-18事件内部2次次级振荡及转型特征与低纬记录基本一致,表明低纬过程在MIS4/3转换时期对于EASM强度存在直接调制作用,该过程可能与热带印度洋-太平洋暖池热力异常、热带辐合带(ITCZ)南北移动的协同效应密切相关。 展开更多
关键词 mis4/3 东亚夏季风增强事件 先兆性事件 事件结构 低纬过程 石笋
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MMHCA:Multi-feature representations based on multi-scale hierarchical contextual aggregation for UAV-view geo-localization 被引量:2
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作者 Nanhua CHEN Tai-shan LOU Liangyu ZHAO 《Chinese Journal of Aeronautics》 2025年第6期517-532,共16页
In global navigation satellite system denial environment,cross-view geo-localization based on image retrieval presents an exceedingly critical visual localization solution for Unmanned Aerial Vehicle(UAV)systems.The e... In global navigation satellite system denial environment,cross-view geo-localization based on image retrieval presents an exceedingly critical visual localization solution for Unmanned Aerial Vehicle(UAV)systems.The essence of cross-view geo-localization resides in matching images containing the same geographical targets from disparate platforms,such as UAV-view and satellite-view images.However,images of the same geographical targets may suffer from occlusions and geometric distortions due to variations in the capturing platform,view,and timing.The existing methods predominantly extract features by segmenting feature maps,which overlook the holistic semantic distribution and structural information of objects,resulting in loss of image information.To address these challenges,dilated neighborhood attention Transformer is employed as the feature extraction backbone,and Multi-feature representations based on Multi-scale Hierarchical Contextual Aggregation(MMHCA)is proposed.In the proposed MMHCA method,the multiscale hierarchical contextual aggregation method is utilized to extract contextual information from local to global across various granularity levels,establishing feature associations of contextual information with global and local information in the image.Subsequently,the multi-feature representations method is utilized to obtain rich discriminative feature information,bolstering the robustness of model in scenarios characterized by positional shifts,varying distances,and scale ambiguities.Comprehensive experiments conducted on the extensively utilized University-1652 and SUES-200 benchmarks indicate that the MMHCA method surpasses the existing techniques.showing outstanding results in UAV localization and navigation. 展开更多
关键词 Geo-localization Image retrieval UAV Hierarchical contextual aggregation Multi-feature representations
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On the representations of string pairs over virtual field
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作者 TAO Kun FU Chang-Jian 《四川大学学报(自然科学版)》 北大核心 2025年第5期1103-1108,共6页
Let F_(1)be the virtual field consisting of one element and(Q,I)a string pair.In this paper,we study the representations of string pairs over the virtual field F_(1).It is proved that an indecomposable F_(1)-represent... Let F_(1)be the virtual field consisting of one element and(Q,I)a string pair.In this paper,we study the representations of string pairs over the virtual field F_(1).It is proved that an indecomposable F_(1)-representation is either a string representation or a band representation by using the coefficient quivers.It is worth noting that for a given band and a positive integer,there exists a unique band representation up to isomorphism. 展开更多
关键词 string pair string representation band representation
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MIS 4/3转型期北太平洋亚热带流涡区浮游有孔虫Globorotalia truncatulinoides的分布特征及其古气候意义
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作者 张超 胡镕 《第四纪研究》 北大核心 2025年第2期448-455,共8页
北太平洋模态水传递表层海水信号至温跃层,对北太平洋营养物质和碳循环起到重要作用。本研究分析了现代黑潮延伸体核心区总长为4.89 m的KEC钻孔70 ka以来浮游有孔虫Globorotalia truncatulinoides左右旋含量,发现MIS 4期间G.truncatulin... 北太平洋模态水传递表层海水信号至温跃层,对北太平洋营养物质和碳循环起到重要作用。本研究分析了现代黑潮延伸体核心区总长为4.89 m的KEC钻孔70 ka以来浮游有孔虫Globorotalia truncatulinoides左右旋含量,发现MIS 4期间G.truncatulinoides以左旋占绝对优势,而进入MIS 3后则突变为右旋。这种MIS 4/3转型期间G.truncatulinoides的旋向变化在北太平洋副热带流涡(NPSG)影响范围内广泛存在,而在南太平洋、大西洋却没有类似的现象。这一独特现象可能与MIS 4期间北太平洋模态水形成的增强密切相关。这种加强可能归因于当时显著降低的大气和海洋温度,以及亚北极锋的南移。G.truncatulinoides旋向的转变,为NPSG范围内深海沉积物中MIS 4/3阶段的生物地层划分提供了一个显著标识。这一发现对理解古海洋环流的变化及其对生物群落结构的影响具有重要意义,也为古气候研究提供了新的视角。 展开更多
关键词 Globorotalia truncatulinoides 北太平洋亚热带流涡 mis 4/3转型期
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Advances in small molecule representations and AI-driven drug research:bridging the gap between theory and application 被引量:1
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作者 Junxi Liu Shan Chang +2 位作者 Qingtian Deng Yulian Ding Yi Pan 《Chinese Journal of Natural Medicines》 2025年第11期1391-1408,共18页
Artificial intelligence(AI)researchers and cheminformatics specialists strive to identify effective drug precursors while optimizing costs and accelerating development processes.Digital molecular representation plays ... Artificial intelligence(AI)researchers and cheminformatics specialists strive to identify effective drug precursors while optimizing costs and accelerating development processes.Digital molecular representation plays a crucial role in achieving this objective by making molecules machine-readable,thereby enhancing the accuracy of molecular prediction tasks and facilitating evidence-based decision making.This study presents a comprehensive review of small molecular representations and AI-driven drug discovery downstream tasks utilizing these representations.The research methodology begins with the compilation of small molecule databases,followed by an analysis of fundamental molecular representations and the models that learn these representations from initial forms,capturing patterns and salient features across extensive chemical spaces.The study then examines various drug discovery downstream tasks,including drug-target interaction(DTI)prediction,drug-target affinity(DTA)prediction,drug property(DP)prediction,and drug generation,all based on learned representations.The analysis concludes by highlighting challenges and opportunities associated with machine learning(ML)methods for molecular representation and improving downstream task performance.Additionally,the representation of small molecules and AI-based downstream tasks demonstrates significant potential in identifying traditional Chinese medicine(TCM)medicinal substances and facilitating TCM target discovery. 展开更多
关键词 Small molecular representation Drug-target interaction prediction Drug-target affinity prediction Drug property prediction De novo drug generation Traditional Chinese medicine
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碳掺杂对GaN MIS-HEMT热阻的调控机制研究
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作者 杜嘉鑫 王冲 +2 位作者 丁小龙 陈财 黄永 《固体电子学研究与进展》 2025年第6期87-94,共8页
针对封装GaN MIS‐HEMT器件,采用实验结合仿真(ANSYS Icepak)的方式,系统研究了缓冲层碳掺杂浓度对热阻的调控机制。通过瞬态热测试(T3Ster)获得了器件的瞬态热阻抗曲线和微分、积分函数,建立了基于器件各物理层的5阶Cauer型RC热网络模... 针对封装GaN MIS‐HEMT器件,采用实验结合仿真(ANSYS Icepak)的方式,系统研究了缓冲层碳掺杂浓度对热阻的调控机制。通过瞬态热测试(T3Ster)获得了器件的瞬态热阻抗曲线和微分、积分函数,建立了基于器件各物理层的5阶Cauer型RC热网络模型。实验结果显示,碳掺杂浓度升高导致结壳热阻上升9.9%,其中芯片层热阻增幅达31.2%;仿真结果验证了碳掺杂可以使缓冲层热导率下降90%以上,导致温度梯度非线性增大。基于Debye‐Callaway模型的理论分析表明,GaN缓冲层中由碳掺杂引起的声子-点缺陷散射主导热导率退化。 展开更多
关键词 GAN mis-HEMT 碳掺杂 瞬态热测试 热阻 声子散射
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“Representation”的基本语义与中译名辨析
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作者 周建增 《文艺理论研究》 北大核心 2025年第2期55-67,141,共14页
“Representation”概念具有一个由多民族语言构成的词汇谱系。此一谱系的语义内核为替代,兼涉自我与他者,展现出一种在场的摇摆特性。以此观之,“再现”虽具备他者指涉内涵,却往往被视为模仿的另一种表述;再现还被用以翻译“reproduct... “Representation”概念具有一个由多民族语言构成的词汇谱系。此一谱系的语义内核为替代,兼涉自我与他者,展现出一种在场的摇摆特性。以此观之,“再现”虽具备他者指涉内涵,却往往被视为模仿的另一种表述;再现还被用以翻译“reproduction”,后者也是模仿的代名词。“表征”尽管突破了模仿的思路,试图涵盖“representation”的自我和他者面向;但是其古代汉语内涵和当代科技中文运用与“representation”原义不相凿枘。“表象”自古具有象征、代表和表示之义,能够涵盖“representation”的客体化和动作化意味。现代汉语翻译实践印证了这一点。所以,与再现、表征相比,表象更适合成为“representation”的主要中译名。将“representation”中译名拟定为表象,能够更好地释放出这一概念自身的理论潜能,以及它与中国文论的对话潜能。对“representation”概念进行语义学和中译名考察,乃尝试以还原、释义和正名之法,探讨异域概念的合适的汉语表达方式,进而寻求中西方文论对话、汇通的可能性。 展开更多
关键词 替代 再现 模仿 表征 表象
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Integrating species diversity, ecosystem services, climate and ecological stability helps to improve spatial representation of protected areas for quadruple win
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作者 Hui Dang Yihe Lü +2 位作者 Xiaofeng Wang Yunqi Hao Bojie Fu 《Geography and Sustainability》 2025年第1期47-57,共11页
Establishing and maintaining protected areas is a pivotal strategy for attaining the post-2020 biodiversity target. The conservation objectives of protected areas have shifted from a narrow emphasis on biodiversity to... Establishing and maintaining protected areas is a pivotal strategy for attaining the post-2020 biodiversity target. The conservation objectives of protected areas have shifted from a narrow emphasis on biodiversity to encompass broader considerations such as ecosystem stability, community resilience to climate change, and enhancement of human well-being. Given these multifaceted objectives, it is imperative to judiciously allocate resources to effectively conserve biodiversity by identifying strategically significant areas for conservation, particularly for mountainous areas. In this study, we evaluated the representativeness of the protected area network in the Qin ling Mountains concerning species diversity, ecosystem services, climate stability and ecological stability. The results indicate that some of the ecological indicators are spatially correlated with topographic gradient effects. The conservation priority areas predominantly lie in the northern foothills, the southeastern, and southwestern parts of the Qinling Mountain with areas concentrated at altitudes between 1,500-2,000 m and slopes between 40°-50° as hotspots. The conservation priority areas identified through the framework of inclusive conservation optimization account for 22.9 % of the Qinling Mountain. Existing protected areas comprise only 6.1 % of the Qinling Mountain and 13.18 % of the conservation priority areas. This will play an important role in achiev ing sustainable development in the region and in meeting the post-2020 biodiversity target. The framework can advance the different objectives of achieving a quadruple win and can also be extended to other regions. 展开更多
关键词 Protected areas Nature conservation Ecological representation Qinling Mountains Spatial planning
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Face recognition algorithm using collaborative sparse representation based on CNN features
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作者 ZHAO Shilin XU Chengjun LIU Changrong 《Journal of Measurement Science and Instrumentation》 2025年第1期85-95,共11页
Considering that the algorithm accuracy of the traditional sparse representation models is not high under the influence of multiple complex environmental factors,this study focuses on the improvement of feature extrac... Considering that the algorithm accuracy of the traditional sparse representation models is not high under the influence of multiple complex environmental factors,this study focuses on the improvement of feature extraction and model construction.Firstly,the convolutional neural network(CNN)features of the face are extracted by the trained deep learning network.Next,the steady-state and dynamic classifiers for face recognition are constructed based on the CNN features and Haar features respectively,with two-stage sparse representation introduced in the process of constructing the steady-state classifier and the feature templates with high reliability are dynamically selected as alternative templates from the sparse representation template dictionary constructed using the CNN features.Finally,the results of face recognition are given based on the classification results of the steady-state classifier and the dynamic classifier together.Based on this,the feature weights of the steady-state classifier template are adjusted in real time and the dictionary set is dynamically updated to reduce the probability of irrelevant features entering the dictionary set.The average recognition accuracy of this method is 94.45%on the CMU PIE face database and 96.58%on the AR face database,which is significantly improved compared with that of the traditional face recognition methods. 展开更多
关键词 sparse representation deep learning face recognition dictionary update feature extraction
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Approximate-Guided Representation Learning in Vision Transformer
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作者 Kaili Wang Xinwei Sun +2 位作者 Huijie He Fenhua Bai Tao Shen 《CAAI Transactions on Intelligence Technology》 2025年第5期1459-1477,共19页
In recent years,the transformer model has demonstrated excellent performance in computer vision(CV)applications.The key lies in its guided representation attention mechanism,which uses dot-product to depict complex fe... In recent years,the transformer model has demonstrated excellent performance in computer vision(CV)applications.The key lies in its guided representation attention mechanism,which uses dot-product to depict complex feature relationships,and comprehensively understands the context semantics to obtain feature weights.Then feature enhancement is implemented by guiding the target matrix through feature weights.However,the uncertainty and inconsistency of features are widespread that prone to confusion in the description of relationships within dot-product attention mechanisms.To solve this problem,this paper proposed a novel approximate-guided representation learning methodology for vision transformer.The kernelised matroids fuzzy rough set is defined,wherein the closed sets inside kernelised fuzzy information granules of matroids structures can constitute the subspace of lower approximation in rough sets.Thus,the kernel relation is employed to characterise image feature granules that will be reconstructed according to the independent set in matroids theory.Then,according to the characteristics of the closed set within matroids,the feature attention weight is formed by using the lower approximation to realise the approximate guidance of features.The approximate-guided representation mechanism can be flexibly deployed as a plug-and-play component in a wide range of CV tasks.Extensive empirical results demonstrate that the proposed method outperforms the majority of advanced prevalent models,especially in terms of robustness. 展开更多
关键词 computer vision deep learning image representation kernel methods rough sets
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Automatic clustering of single-molecule break junction data through task-oriented representation learning
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作者 Yi-Heng Zhao Shen-Wen Pang +4 位作者 Heng-Zhi Huang Shao-Wen Wu Shao-Hua Sun Zhen-Bing Liu Zhi-Chao Pan 《Rare Metals》 2025年第5期3244-3257,共14页
Clustering is a pivotal data analysis method for deciphering the charge transport properties of single molecules in break junction experiments.However,given the high dimensionality and variability of the data,feature ... Clustering is a pivotal data analysis method for deciphering the charge transport properties of single molecules in break junction experiments.However,given the high dimensionality and variability of the data,feature extraction remains a bottleneck in the development of efficient clustering methods.In this regard,extensive research over the past two decades has focused on feature engineering and dimensionality reduction in break junction conductance.However,extracting highly relevant features without expert knowledge remains an unresolved challenge.To address this issue,we propose a deep clustering method driven by task-oriented representation learning(CTRL)in which the clustering module serves as a guide for the representation learning(RepL)module.First,we determine an optimal autoencoder(AE)structure through a neural architecture search(NAS)to ensure efficient RepL;second,the RepL process is guided by a joint training strategy that combines AE reconstruction loss with the clustering objective.The results demonstrate that CTRL achieves excellent performance on both the generated and experimental data.Further inspection of the RepL step reveals that joint training robustly learns more compact features than the unconstrained AE or traditional dimensionality reduction methods,significantly reducing misclustering possibilities.Our method provides a general end-to-end automatic clustering solution for analyzing single-molecule break junction data. 展开更多
关键词 Single-molecule conductance Break junction Deep clustering representation learning Neural architecture search
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GaN MIS-HEMT的PBTI效应研究
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作者 丁小龙 王冲 +1 位作者 杜嘉鑫 黄永 《固体电子学研究与进展》 2025年第6期16-22,共7页
本研究系统探讨栅介质层厚度对GaN MIS-HEMT器件正栅偏置温度不稳定性(Positive gate bias tem⁃perature instability,PBTI)的影响机制。实验选取了40 nm和60 nm SiN栅介质层MIS-HEMT器件,结果表明,PBTI应力过程中阈值漂移量呈现对数时... 本研究系统探讨栅介质层厚度对GaN MIS-HEMT器件正栅偏置温度不稳定性(Positive gate bias tem⁃perature instability,PBTI)的影响机制。实验选取了40 nm和60 nm SiN栅介质层MIS-HEMT器件,结果表明,PBTI应力过程中阈值漂移量呈现对数时间依赖性,恢复阶段中阈值漂移的时间演化遵循幂律规律。长时间应力对输出特性和栅漏电无显著影响,但可能导致场板区域出现空洞缺陷。通过构建临界栅应力阈值(V_(f))模型,揭示了栅介质厚度对PBTI效应的双重作用机制:当栅压V_(g)<V_(f)时,薄栅介质(40 nm)器件因强电场效应促使更多沟道电子隧穿AlGaN势垒层并俘获于介质层/AlGaN界面态,导致阈值稳定性更差;当V_(g)>V_(f)时,电场作用趋于饱和,厚栅介质(60 nm)器件因更大的应力累积,诱导产生更高密度的SiN/AlGaN界面态和介质体缺陷态(D_(it)=3.63×10^(13) cm^(−2)eV^(−1)),导致电子俘获效应显著增强,产生更大的正漂移量。 展开更多
关键词 GAN mis-HEMT PBTI 栅介质厚度 阈值电压稳定性
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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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An adaptive dual-domain feature representation method for enhanced deep forgery detection
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作者 Ming Li Yan Qin +1 位作者 Heng Zhang Zhiguo Shi 《Journal of Automation and Intelligence》 2025年第4期273-281,共9页
Deep forgery detection technologies are crucial for image and video recognition tasks,with their performance heavily reliant on the features extracted from both real and fake images.However,most existing methods prima... Deep forgery detection technologies are crucial for image and video recognition tasks,with their performance heavily reliant on the features extracted from both real and fake images.However,most existing methods primarily focus on spatial domain features,which limits their accuracy.To address this limitation,we propose an adaptive dual-domain feature representation method for enhanced deep forgery detection.Specifically,an adaptive region dynamic convolution module is established to efficiently extract facial features from the spatial domain.Then,we introduce an adaptive frequency dynamic filter to capture effective frequency domain features.By fusing both spatial and frequency domain features,our approach significantly improves the accuracy of classifying real and fake facial images.Finally,experimental results on three real-world datasets validate the effectiveness of our dual-domain feature representation method,which substantially improves classification precision. 展开更多
关键词 Dynamic convolution module Dynamic filter Feature representation Facial images Deep forgery detection
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基于翻转课堂教学模式的“MIS”课程设计研究
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作者 刘洁澜 《教育教学论坛》 2025年第23期137-140,共4页
在教育现代化的推动下,高校持续推进教学模式创新。线上线下混合式教学理念已经在全国各省市的高等教育院校逐渐普及起来。其中,翻转课堂教学模式成为教育类期刊讨论较多的热点话题,主要围绕其教学理论和课堂实践展开。以“MIS(管理信... 在教育现代化的推动下,高校持续推进教学模式创新。线上线下混合式教学理念已经在全国各省市的高等教育院校逐渐普及起来。其中,翻转课堂教学模式成为教育类期刊讨论较多的热点话题,主要围绕其教学理论和课堂实践展开。以“MIS(管理信息系统)”课程为例,对传统管理信息系统授课方式进行翻转。教师运用教学课件、题库、ERP系统案例和视频讲解,对课程进行了课前、课中、课后的分段式翻转教学设计,学生在课后可以通过EQ云平台进行课程的预习和拓展,使得教学效果受到了学生的好评。 展开更多
关键词 翻转课堂 mis课程 教学准备建议
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