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基于图优化的容差关系粗糙集分布式算法
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作者 吴正江 武星晨 +1 位作者 连涛 王梦松 《计算机工程》 北大核心 2026年第3期346-354,共9页
为了处理分布式的不完备信息系统(IIS)中的数据筛选问题,研究人员引入了容差关系粗糙集理论。随着数据量的不断增长,需要通过分布式计算来实现可扩展的并行化计算,因此分布式容差关系粗糙集被提出,其中Block Set是计算近似集的核心方法... 为了处理分布式的不完备信息系统(IIS)中的数据筛选问题,研究人员引入了容差关系粗糙集理论。随着数据量的不断增长,需要通过分布式计算来实现可扩展的并行化计算,因此分布式容差关系粗糙集被提出,其中Block Set是计算近似集的核心方法。然而,Block Set在计算时仅使用集合运算,数据之间没有结构,过程涉及大量重复计算,导致计算效率不高。针对这一问题,提出一种基于图优化的容差关系粗糙集分布式(TRDG)算法。引用已有的可靠元和争议元的概念,以IIS中的数据为结点,以非对称容差关系为边,构建具有层次关系的有向无环图,使用图结构来组织数据。为了提高Block Set在分布式环境中的计算效率,提出使用最近容差关系代替一般非对称容差关系的策略,用于删除冗余边,简化图结构,并基于可靠元到零出度争议元的路径来得到Block Set。然后,在Spark平台上实现分布式的图优化算法和路径搜索算法,最终完成TRDG算法的设计。实验结果表明,TRDG算法具有良好的并行加速性能,和传统的容差关系粗糙近似集求解算法相比,TRDG能够节省计算资源,计算速度平均提高了40倍,可处理的数据量也增加了50倍以上。 展开更多
关键词 有向无环图 Block 容差关系粗糙集 最近容差关系 近似集分布式计算
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Hyponormal Block Toeplitz Operators on the Weighted Bergman Space with Circulant Symbols
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作者 FU Guangyang ZHOU Jiang 《数学进展》 北大核心 2026年第1期183-191,共9页
In this paper,we present a necessary and sufficient condition for hyponormal block Toeplitz operators T on the vector-valued weighted Bergman space with symbolsΦ(z)=G^(*)(z)+F(z),where F(z)=∑^(N)_(i)=1 A_(i)z^(i)and... In this paper,we present a necessary and sufficient condition for hyponormal block Toeplitz operators T on the vector-valued weighted Bergman space with symbolsΦ(z)=G^(*)(z)+F(z),where F(z)=∑^(N)_(i)=1 A_(i)z^(i)and G(z)=∑^(N)_(i)=1 A_(−i)z^(i),A_(i)ae culants. 展开更多
关键词 block Toeplitz operator hyponormal weighted Bergman space CIRCULANT COMMUTATOR
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A case report with the progression from atrial fibrillation to complete AV block, heart failure and electrical storm
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作者 Shi-Xing LI Xiang-Min SHI +1 位作者 Jian LI Chuang ZHANG 《Journal of Geriatric Cardiology》 2026年第1期65-68,共4页
When patients initially present with atrial fibrillation along with an enlarged heart and heart failure, followed by atrioventricular block, it's essential to consider genetic factors.^([1])Genetic testing can off... When patients initially present with atrial fibrillation along with an enlarged heart and heart failure, followed by atrioventricular block, it's essential to consider genetic factors.^([1])Genetic testing can offer crucial diagnostic evidence, aiding in prognosis assessment and the adoption of appropriate treatment strategies. 展开更多
关键词 heart failure atrial fibrillation enlarged heart atrioventricular block genetic factors genetic testing adoption appropriate treatment strategies complete av block prognosis assessment
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Engineering repairable nanoporous functional coatings on arbitrary substrates by manipulating phase behaviors of block copolymers
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作者 Jiemei Zhou Xiang Ying +3 位作者 Daiwen Li Mingjie Wei Xiangyue Ye Yong Wang 《Chinese Journal of Chemical Engineering》 2026年第1期36-46,共11页
Nanoporous polymers are extensively coated on various substrates to deliver optical,permselective,or other functions.However,it remains desired to fast produce uniform nanoporous polymer coatings on substrates with co... Nanoporous polymers are extensively coated on various substrates to deliver optical,permselective,or other functions.However,it remains desired to fast produce uniform nanoporous polymer coatings on substrates with complex surfaces.Herein,by manipulating the interactions between block copolymers and selective solvents,we prepare repairable nanoporous polymers on arbitrary substrates.This is realized by an extremely simple sequential coating process:sequential coating of block copolymers and their swelling agents on substrate surfaces.The swelling agents are comprised of two solvents that swell the constituent blocks of the copolymers to different degrees,rapidly producing polymer coatings with uniform,interconnected,sub-50 nm pores.This sequential coating process is able to conformally build nanoporous polymers on nonplanar substrates with large lateral sizes and complex surface features,and also to in situ repair defects arising during usages.We further demonstrate that the nanoporous coatings show excellent antireflective and membrane separation performances.This sequential coating process is dictated by polymer–solvent interactions,and is expected to find applications in diverse fields for its simplicity,adaptability,and the capability to produce well-defined nanoporosities. 展开更多
关键词 Nanoporous coating Block copolymers Selective swelling Polymer-solvent interactions ANTIREFLECTION
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The Enhancement of Mechanical Stretchability for Stretchable Organic Solar Cells
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作者 WANG Minshuai CAI Xiaomei ZHENG Kai 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期547-552,共6页
To evaluate their performance,we constructed organic solar cells using PTB7/Y6 and PTB7-b-PNDI active layers,which were deposited on PET substrates coated with PEDOT:PSS.The ternary solar cells demonstrated an excelle... To evaluate their performance,we constructed organic solar cells using PTB7/Y6 and PTB7-b-PNDI active layers,which were deposited on PET substrates coated with PEDOT:PSS.The ternary solar cells demonstrated an excellent power conversion efficiency after being stretched by 38%.The stretchable organic solar cells were spin-coated on the flexible substrate.The electrodes were formed via liquid metal dropcoating.Solar cell devices based on PET/PH1000/PEDOT:PSS and PTB7:Y6:5% BCP active layer materials show better stretchability than the normal solar cells.The PTB7:Y6:5% BCP-based stretchable organic solar cell achieves a high PCE of 12.3%,and a PCE of 7.8% after stretching.Incorporating block copolymer additives improves the mechanical properties of organic solar cells,thereby enabling superior stretchability. 展开更多
关键词 STRETCHABLE organic photovoltaics mechanical properties block copolymer
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Engineering stimuli-responsive block copolymers for multimodal bioimaging
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作者 Lizhuang Zhong Ming Liu +3 位作者 Shilong Su Dongxin Zeng Jing Hu Zhiqian Guo 《Chinese Chemical Letters》 2026年第1期116-124,共9页
The diagnostic efficacy of contemporary bioimaging technologies remains constrained by inherent limitations of conventional imaging agents,including suboptimal sensitivity,off-target biodistribution,and inherent cytot... The diagnostic efficacy of contemporary bioimaging technologies remains constrained by inherent limitations of conventional imaging agents,including suboptimal sensitivity,off-target biodistribution,and inherent cytotoxicity.These limitations have catalyzed the development of intelligent stimuli-responsive block copolymers-based bioimaging agents,which was engineered to dynamically respond to endogenous biochemical cues(e.g.,p H gradients,redox potential,enzyme activity,hypoxia environment) or exogenous physical triggers(e.g.,photoirradiation,thermal gradients,ultrasound(US)/magnetic stimuli).Through spatiotemporally controlled structural transformations,stimuli-responsive block copolymers enable precise contrast targeting,activatable signal amplification,and theranostic integration,thereby substantially enhancing signal-to-noise ratios of bioimaging and diagnostic specificity.Hence,this mini-review systematically examines molecular engineering principles for designing p H-,redox-,enzyme-,light-,thermo-,and US/magnetic-responsive polymers,with emphasis on structure-property relationships governing imaging performance modulation.Furthermore,we critically analyze emerging strategies for optical imaging,US synergies,and magnetic resonance imaging(MRI).Multimodal bioimaging has also been elaborated,which could overcome the inherent trade-offs between resolution,penetration depth,and functional specificity in single-modal approaches.By elucidating mechanistic insights and translational challenges,this mini-review aims to establish a design framework of stimuli-responsive block copolymersbased for high fidelity bioimaging agents and accelerate their clinical translation in precise diagnosis and therapy. 展开更多
关键词 STIMULI-RESPONSIVE Block copolymers Molecular engineering Multimodal bioimaging Diagnosis and therapy
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FDEFusion:End-to-End Infrared and Visible Image Fusion Method Based on Frequency Decomposition and Enhancement
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作者 Ming Chen Guoqiang Ma +3 位作者 Ping Qi Fucheng Wang Lin Shen Xiaoya Pi 《Computers, Materials & Continua》 2026年第4期817-839,共23页
In the image fusion field,fusing infrared images(IRIs)and visible images(VIs)excelled is a key area.The differences between IRIs and VIs make it challenging to fuse both types into a high-quality image.Accordingly,eff... In the image fusion field,fusing infrared images(IRIs)and visible images(VIs)excelled is a key area.The differences between IRIs and VIs make it challenging to fuse both types into a high-quality image.Accordingly,efficiently combining the advantages of both images while overcoming their shortcomings is necessary.To handle this challenge,we developed an end-to-end IRI andVI fusionmethod based on frequency decomposition and enhancement.By applying concepts from frequency domain analysis,we used the layering mechanism to better capture the salient thermal targets from the IRIs and the rich textural information from the VIs,respectively,significantly boosting the image fusion quality and effectiveness.In addition,the backbone network combined Restormer Blocks and Dense Blocks;Restormer blocks utilize global attention to extract shallow features.Meanwhile,Dense Blocks ensure the integration between shallow and deep features,thereby avoiding the loss of shallow attributes.Extensive experiments on TNO and MSRS datasets demonstrated that the suggested method achieved state-of-the-art(SOTA)performance in various metrics:Entropy(EN),Mutual Information(MI),Standard Deviation(SD),The Structural Similarity Index Measure(SSIM),Fusion quality(Qabf),MI of the pixel(FMI_(pixel)),and modified Visual Information Fidelity(VIF_(m)). 展开更多
关键词 Infrared images visible images frequency decomposition restormer blocks global attention
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Unraveling the exhumation history of the source terrains of the western Jianghan Basin(Central China)through detrital zircon fission track dating
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作者 HAN Siyu LIN Xu +1 位作者 LIU Weiming LIU Haijin 《Journal of Mountain Science》 2026年第1期49-66,共18页
The Jianghan Basin,at the junction of the Jiangnan and Qinling-Dabie orogenic belts,has a complete Cretaceous to Paleogene stratigraphic record.However,the exhumation history of its source terrains is not well underst... The Jianghan Basin,at the junction of the Jiangnan and Qinling-Dabie orogenic belts,has a complete Cretaceous to Paleogene stratigraphic record.However,the exhumation history of its source terrains is not well understood.We conducted fission track age analysis on zircon grains(n=441)from the Cretaceous and Paleogene strata in the western Jianghan Basin.The Radial Plotter software is utilized to identify peak ages that indicate thermal events and the history of exhumation.The oldest peak at 810 Ma records the Neoproterozoic collisional orogeny between the Yangtze Craton and Cathaysian Block.Ages of 645-558 Ma reflect the convergence between the South China Block and Gondwana.Early Paleozoic ages document the collision leading to the exhumation of the western Jiangnan Orogenic Belt.Late Paleozoic to early Mesozoic peak ages correspond to the Indosinian orogeny.During the Mesozoic,the subduction of the Paleo-Pacific Plate resulted in further exhumation.The absence of Paleogene zircon fission track peak ages in the basin strata suggests limited exhumation during this period,likely due to tectonic quiescence and arid climatic conditions. 展开更多
关键词 Jianghan Basin Detrital zircon Fission track PALEOGEOGRAPHY South China Block
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TP-ViT:truncated uniform-log2 quantizer and progressive bit-decline reconstruction for vision Transformer quantization
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作者 Xichuan ZHOU Sihuan ZHAO +4 位作者 Rui DING Jiayu SHI Jing NIE Lihui CHEN Haijun LIU 《ENGINEERING Information Technology & Electronic Engineering》 2026年第1期47-58,共12页
Vision Transformers(ViTs)have achieved remarkable success across various artificial intelligence-based computer vision applications.However,their demanding computational and memory requirements pose significant challe... Vision Transformers(ViTs)have achieved remarkable success across various artificial intelligence-based computer vision applications.However,their demanding computational and memory requirements pose significant challenges for de-ployment on resource-constrained edge devices.Although post-training quantization(PTQ)provides a promising solution by reducing model precision with minimal calibration data,aggressive low-bit quantization typically leads to substantial perfor-mance degradation.To address this challenge,we present the truncated uniform-log2 quantizer and progressive bit-decline reconstruction method for vision Transformer quantization(TP-ViT).It is an innovative PTQ framework specifically designed for ViTs,featuring two key technical contributions:(1)truncated uniform-log2 quantizer,a novel quantization approach which effectively handles outlier values in post-Softmax activations,significantly reducing quantization errors;(2)bit-decline optimiza-tion strategy,which employs transition weights to gradually reduce bit precision while maintaining model performance under extreme quantization conditions.Comprehensive experiments on image classification,object detection,and instance segmenta-tion tasks demonstrate TP-ViT’s superior performance compared to state-of-the-art PTQ methods,particularly in challenging 3-bit quantization scenarios.Our framework achieves a notable 6.18 percentage points improvement in top-1 accuracy for ViT-small under 3-bit quantization.These results validate TP-ViT’s robustness and general applicability,paving the way for more efficient deployment of ViT models in computer vision applications on edge hardware. 展开更多
关键词 Vision Transformers Post-training quantization Block reconstruction Image classification Object detection Instance segmentation
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Metamorphic P-T-t Evolution and Tectonic Implications of High-pressure Granulites in the Qushan Islands,East China Sea
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作者 CAO Yiwen ZHOU Xiwen +1 位作者 DONG Jie DENG Xuanyu 《Acta Geologica Sinica(English Edition)》 2026年第1期69-81,共13页
Debate has persisted over whether the metamorphic basement of the Zhoushan Islands,easternmost Cathaysia Block,is Precambrian.Here,representative metamorphic rocks from the Qushan Islands were investigated using petro... Debate has persisted over whether the metamorphic basement of the Zhoushan Islands,easternmost Cathaysia Block,is Precambrian.Here,representative metamorphic rocks from the Qushan Islands were investigated using petrography,mineral chemistry,phase equilibria modeling and SHRIMP zircon U-Pb dating to constrain their metamorphic evolution and tectonic significance.Both the pelitic granulites(garnet-kyanite-perthite-biotite-quartz)and the mafic granulites(garnet-clinopyroxene-amphibole-plagioclase-quartz)reached high-pressure granulite-facies conditions of 1.2-1.4 GPa/820-900℃,and recorded three metamorphic stages along a clockwise P-T path with post-peak isothermal decompression.This trajectory indicated rapid exhumation of thickened continental crust during collisional orogeny.Metamorphic ages of 254±3 Ma,262±4 Ma and 259±3 Ma were obtained for mafic granulite,pelitic granulite and marble,respectively,and were consistent with the emplacement age of 259±4 Ma for a pegmatite vein.Detrital zircons in metasediments spanned 2706-330 Ma,which constrained the latest deposition to~330 Ma;thus represented mid-Paleozoic sediment metamorphosed during the late Paleozoic rather than Precambrian basement.We conclude that the Indosinian tectonothermal event in the Cathaysia Block had originated from late Paleozoic-early Mesozoic collisional orogeny between the South China Plate to the north and the Indochina Block to the south. 展开更多
关键词 METAMORPHISM high-pressure granulite zircon U-Pb dating Qushan Islands East China Sea Cathaysia Block
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Magnetic fabric of the late Miocene extrusive rocks of the Combia Volcanic Province:Tectonic implications for the northern Andes
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作者 Victor A.Piedrahita Martin Chadima +3 位作者 Jackeline Ramírez Alejandra Tabares Maria I.Marín-Cerón JinHua Li 《Earth and Planetary Physics》 2026年第1期44-56,共13页
The accretion of the Panama-ChocóBlock to the South American Plate partially drove the geological setting of the northern Andes.This event occurred in different collisional stages that are recorded in Oligocene-m... The accretion of the Panama-ChocóBlock to the South American Plate partially drove the geological setting of the northern Andes.This event occurred in different collisional stages that are recorded in Oligocene-middle Miocene deformed rocks of the inter-Andean valley between the Western and Central Cordilleras of Colombia.However,uncertainty remains about the age of the latest accretionary phases of the Panama-ChocóBlock.Poorly studied late Miocene volcanic rocks within the northern inter-Andean valley may provide key information to constrain the temporality of that final collision.Here,we study the deformational features of the~12-6 Ma extrusive rocks of the Combia Volcanic Province located in the northwestern Andes(Colombia).We present anisotropy of magnetic susceptibility(AMS)data for pyroclastic and volcanic rocks within the AmagáBasin,an inter-Andean depression with Oligocene-middle Miocene sedimentary rocks that recorded NW-SE compression and NE-SW simple shear caused by the Panama-ChocóBlock collision.We identified that the magnetic fabrics of the extrusive rocks of the Combia Volcanic Province reveal flow directions that indicate the occurrence of ancient volcanoes in the central axis of the AmagáBasin.Some of these fabrics do not contain any deformational features,whereas others record the same structural regime as the Oligocene-middle Miocene sedimentary rocks.We infer that variations in the intensity of the deformation promoted late Miocene local fault reactivations that,in contrast to the Oligocene-middle Miocene deformational events,did not affect the entire AmagáBasin.Age differences among the studied sections can also explain the different deformational patterns identified in the basin.Both interpretations suggest that the most significant collisional events of the Panama-ChocóBlock occurred in the Oligocene-middle Miocene,whereas the formation of the Combia Volcanic Province may have either followed or coincided with the latest stages of the accretion. 展开更多
关键词 Combia Volcanic Province Panama-ChocóBlock magnetic fabric deformation flow direction
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Flowback Behavior of Deep Coalbed Methane Horizontal Wells
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作者 Wei Sun Yanqing Feng +4 位作者 Yuan Wang Zengping Zhao Qian Wang Xiangyun Li Dong Feng 《Fluid Dynamics & Materials Processing》 2026年第1期173-191,共19页
Significant differences exist between deep and medium-shallow coalbed methane(CBM)reservoirs.The unclear understanding of flowback and production behavior severely constrains the development of deep CBM resources.To a... Significant differences exist between deep and medium-shallow coalbed methane(CBM)reservoirs.The unclear understanding of flowback and production behavior severely constrains the development of deep CBM resources.To address this challenge,guided by the gas-liquid two-phase flow theory in ultra-low permeability reservoirs,and integrating theoretical analysis,numerical simulation,and insights from production practices,this study classifies the flowback and production stages of deep CBM well considering the Daning-Jixian Block,Eastern Ordos Basin as a representative case.We summarize the flowback characteristics for each stage and establish a standard flowback production type curve,aiming to guide field operations.The results indicate that:(a)The production process of deep CBM horizontal wells can be divided into five distinct stages:initial single-phase water dewatering stage,initial gas appearance to peak water production stage,gas breakthrough to peak gas production stage,stable production and decline stage,and low-rate production stage.(b)Based on reservoir energy,two standard type curves for horizontal well flowback production are established:the‘Sufficient Reservoir Energy’type and the‘Insufficient Reservoir Energy’type.The former achieves a higher initial gas rate(up to 12×10^(4)m^(3)/d)but exhibits poorer stability,while the latter achieves a lower stable rate(up to 8×10^(4)m^(3)/d)but demonstrates stronger stability.Numerical simulation confirms these behavioral patterns and reveals the underlying mechanisms related to the effectively drained area where pressure is significantly depleted.The findings from this study have guided the flowback production operations in 53 deep CBM wells with positive results,demonstrating high potential for broad application. 展开更多
关键词 Daning-Jixian Block deep coalbed methane horizontal well reservoir energy flowback production behavior
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The Magic of Organocatalytic Synergism in Switchable Polymerization:One-pot Synthesis of Block Copolymers with Programmable Sequences and Compositions
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作者 Shuai-Shuai Zhu Mao-Ji Zhao +1 位作者 Ying-Jie Yuan Yong Wang 《Chinese Journal of Polymer Science》 2026年第1期68-78,I0010,共12页
Switchable polymerization is emerging as a powerful tool to construct block copolymers directly from mixtures of monomers.However,current achievements typically iterate between two polymerization cycles to afford prod... Switchable polymerization is emerging as a powerful tool to construct block copolymers directly from mixtures of monomers.However,current achievements typically iterate between two polymerization cycles to afford products with fixed sequences and compositions.Herein,we report the triethylborane/1,8-diazabicyclo[5.4.0]undec-7-ene(Et_3B/DBU)pair-mediated four-component switchable polymerization of propylene oxide(PO),CO_(2),phthalic anhydride(PA),and racemic lactide(rac-LA),which enables the on-demand synthesis of four different block copolymers,i.e.,poly(propylene phthalate)-b-polylactide(PPE-b-PLA),PPE-b-PLA-b-poly(propylene carbonate)(PPC),PPE-b-PPC-b-PLA,and PPE-b-PPCb-poly(propylene oxide)(PPO),through rationally modulating the Lewis pair(LP)ratio.Core to this protocol is that increasing the loading of Et_(3)B accelerates the ring-opening of PO while impeding the reactivity of rac-LA,thus allowing for fine-tuning of the thermodynamic and kinetic of the switchable polymerization.Therefore,the four polymerization cycles involving PO/PA ring-opening copolymerization(ROCOP),PO/CO_(2) ROCOP,rac-LA ring-opening polymerization(ROP),and PO ROP can be connected and discriminated in precisely programmed manners. 展开更多
关键词 Switchable polymerization Organic Lewis pair Block copolymers Ring-opening copolymerization Multicomponent reaction
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ResghostNet:Boosting GhostNet with Residual Connections and Adaptive-SE Blocks
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作者 Yuang Chen Yong Li +2 位作者 Fang Lin Shuhan Lv Jiaze Jiang 《Computers, Materials & Continua》 2026年第2期1524-1541,共18页
Aiming at the problem of potential information noise introduced during the generation of ghost feature maps in GhostNet,this paper proposes a novel lightweight neural network model called ResghostNet.This model constr... Aiming at the problem of potential information noise introduced during the generation of ghost feature maps in GhostNet,this paper proposes a novel lightweight neural network model called ResghostNet.This model constructs the Resghost Module by combining residual connections and Adaptive-SE Blocks,which enhances the quality of generated feature maps through direct propagation of original input information and selection of important channels before cheap operations.Specifically,ResghostNet introduces residual connections on the basis of the Ghost Module to optimize the information flow,and designs a weight self-attention mechanism combined with SE blocks to enhance feature expression capabilities in cheap operations.Experimental results on the ImageNet dataset show that,compared to GhostNet,ResghostNet achieves higher accuracy while reducing the number of parameters by 52%.Although the computational complexity increases,by optimizing the usage strategy of GPU cachememory,themodel’s inference speed becomes faster.The ResghostNet is optimized in terms of classification accuracy and the number of model parameters,and shows great potential in edge computing devices. 展开更多
关键词 Residual connections adaptive-SE blocks lightweight neural network GPU memory usage
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Action Recognition via Shallow CNNs on Intelligently Selected Motion Data
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作者 Jalees Ur Rahman Muhammad Hanif +2 位作者 Usman Haider Saeed Mian Qaisar Sarra Ayouni 《Computers, Materials & Continua》 2026年第3期2223-2243,共21页
Deep neural networks have achieved excellent classification results on several computer vision benchmarks.This has led to the popularity of machine learning as a service,where trained algorithms are hosted on the clou... Deep neural networks have achieved excellent classification results on several computer vision benchmarks.This has led to the popularity of machine learning as a service,where trained algorithms are hosted on the cloud and inference can be obtained on real-world data.In most applications,it is important to compress the vision data due to the enormous bandwidth and memory requirements.Video codecs exploit spatial and temporal correlations to achieve high compression ratios,but they are computationally expensive.This work computes the motion fields between consecutive frames to facilitate the efficient classification of videos.However,contrary to the normal practice of reconstructing the full-resolution frames through motion compensation,this work proposes to infer the class label from the block-based computed motion fields directly.Motion fields are a richer and more complex representation of motion vectors,where each motion vector carries the magnitude and direction information.This approach has two advantages:the cost of motion compensation and video decoding is avoided,and the dimensions of the input signal are highly reduced.This results in a shallower network for classification.The neural network can be trained using motion vectors in two ways:complex representations and magnitude-direction pairs.The proposed work trains a convolutional neural network on the direction and magnitude tensors of the motion fields.Our experimental results show 20×faster convergence during training,reduced overfitting,and accelerated inference on a hand gesture recognition dataset compared to full-resolution and downsampled frames.We validate the proposed methodology on the HGds dataset,achieving a testing accuracy of 99.21%,on the HMDB51 dataset,achieving 82.54%accuracy,and on the UCF101 dataset,achieving 97.13%accuracy,outperforming state-of-the-art methods in computational efficiency. 展开更多
关键词 Action recognition block matching algorithm convolutional neural network deep learning data compression motion fields optimization videos classification
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Evolution of STBC-Based OFDM-IM for Wireless Vehicular Communication
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作者 Tanairat Mata Pisit Boonsrimuang 《China Communications》 2026年第2期51-68,共18页
This paper studies wireless vehicular communication(VehCom)in intelligent transportation systems using an orthogonal frequency division multiplexing with index modulation(OFDM-IM).In the concept of IM,data is transmit... This paper studies wireless vehicular communication(VehCom)in intelligent transportation systems using an orthogonal frequency division multiplexing with index modulation(OFDM-IM).In the concept of IM,data is transmitted not only through the modulated symbols but also via the indices of the active subcarriers.In contrast to the original OFDM,OFDM-IM activates only non-zero subcarriers,increasing energy efficiency.However,the pilotassisted channel estimation(CE)method is a significant challenge in OFDM-IM,where the desired pilot subcarrier interval is related to the OFDM-IM subblock length.This paper proposes a walsh-scattered pilot-assisted CE for OFDM-IM VehCom.The optimum walsh-scattered pilot assignment is proposed to improve the transmission efficiency.Furthermore,a space-time block code with a high transmit diversity gain is employed for OFDM-IM VehCom to enhance VehCom's signal quality.The results show that the proposed method performs higher CE accuracy and better bit-error rate with significant spectral and energy efficiencies than conventional methods. 展开更多
关键词 index modulation intelligent transportation systems pilot-assisted channel estimation space-time block code wireless vehicular communication
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Slope rockbolting using key block theory:Force transfer and artificial intelligence-assisted multi-objective optimisation
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作者 Jessica Ka Yi Chiu Charlie Chunlin Li +1 位作者 Ole Jakob Mengshoel Vidar Kveldsvik 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期73-91,共19页
This paper presents a novel artificial intelligence(AI)-assisted two-stage method for optimising rock slope stability by integrating advanced 3D modelling with rock support design,aiming at minimising risks,material u... This paper presents a novel artificial intelligence(AI)-assisted two-stage method for optimising rock slope stability by integrating advanced 3D modelling with rock support design,aiming at minimising risks,material usage,and costs.In the first stage,an extended key block analysis identifies key blocks and key block groups,accounting for progressive failure and force interactions.The second stage uses AI algorithms to optimise rockbolting design,balancing stability,cost,and material use.The most efficient algorithms include the multi-objective tree-structured Parzen estimator(MOTPE)and non-dominated sorting genetic algorithms(NSGA-II and NSGA-III).Applied to the Larvik rock slope,the optimised solution uses 18 pre-tensioned cablebolts,providing 13.2 MN of active force and achieving a factor of safety of 1.31 while reducing the average anchorage length by approximately 16%compared to traditional design.The AI-assisted approach also reduces computation time by over 90%compared to Quasi-Monte Carlo(QMC)methods,demonstrating its efficiency for small-scale civil engineering projects and large-scale mining operations.The developed tool is practical,compatible with Building Information Modelling(BIM),and ready for engineering implementation,supporting sustainable and cost-effective rock slope stabilisation.While the method is largely automated,professional judgement remains crucial for verifying ground conditions and selecting the final solution.Future work will focus on integrating data uncertainties,addressing complex block deformation mechanisms,refining optimisation objectives,and improving the performance of multi-objective optimisation for slope rockboling applications to further enhance the method's versatility. 展开更多
关键词 Rock anchoring Slope stability 3D modelling Key block Parametric design Bio-inspired artificial intelligence(AI)
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基于人工智能的疾病检测——以皮肤病为例
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作者 侯宇彤 侯帅 《价值工程》 2026年第7期158-162,共5页
随着移动医疗需求的快速增长,基于人工智能的皮肤病辅助诊断成为研究热点。然而,现有深度学习模型在移动端部署时,普遍存在计算资源消耗与模型精度难以兼顾的挑战。为此,本研究提出并实现了一种轻量化的卷积神经网络模型——WaterfallRe... 随着移动医疗需求的快速增长,基于人工智能的皮肤病辅助诊断成为研究热点。然而,现有深度学习模型在移动端部署时,普遍存在计算资源消耗与模型精度难以兼顾的挑战。为此,本研究提出并实现了一种轻量化的卷积神经网络模型——WaterfallResNet18。该模型以ResNet18为基础,使用自主设计的“瀑布式”残差块替代原有的基础残差块,在有效减少参数量的同时增加了网络深度,能够提取层次更丰富的特征。在公开的HAM10000七分类皮肤病数据集上的实验表明,从头训练的Waterfall-ResNet18模型在收敛速度与分类准确率上均优于原ResNet18模型,有效验证了所提模块的特征增强能力。此外,为推进技术落地,本研究完成了从PyTorch模型训练到TFLite格式转换的完整流程,并开发了可进行离线推理的移动端应用,实现了从算法设计到移动端部署的技术闭环,为皮肤病辅助诊断的移动化应用提供了可行方案。 展开更多
关键词 皮肤病检测 深度学习 卷积神经网络 Waterfall Block ResNet18 移动端部署
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Preparation of low-expansion high-performance Si-C composites based on porous advantage of detoxified and purified waste cathode graphite blocks
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作者 Guoqing Yu Mingzhuang Xie +4 位作者 Zhihao Zheng Zegang Wu Yi Wang Hongliang Zhao Fengqin Liu 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期716-726,共11页
Waste graphitization cathode carbon blocks are a type of hazardous solid waste generated during the aluminum electrolysis process,and their proper disposal is a key step in the resource utilization of discarded graphi... Waste graphitization cathode carbon blocks are a type of hazardous solid waste generated during the aluminum electrolysis process,and their proper disposal is a key step in the resource utilization of discarded graphite.This study utilizes the porous“defect advantage”of a cathode carbon block matrix to prepare silicon-doped and asphalt-coated detoxified and purified waste graphitization cathode carbon blocks for use as high-performance silicon/carbon composite anode materials.The results show that the uniformly silicondoped silicon/carbon composite material features a unique amorphous carbon-encapsulated“locked silicon”structure,which effectively addresses issues such as cathode volume expansion,excessive growth of the solid electrolyte interphase(SEI)film,and poor electrical contact between active materials.Consequently,electrochemical performance is enhanced.After assembly in a half-cell,the PSCC/10%Si@C(purified waste graphitization cathode carbon/10%Si@C)material exhibits optimal electrochemical stability,with an initial charging specific capacity of 514.5 mAh/g at 0.1 C(1 C=170 mA/g)and a capacity retention rate of 95.1%after 100 cycles.At a charge rate of 2.0 C,a specific capacity of 216.9 mAh/g is achieved.This technology provides a new pathway for the economical and high-value utilization of waste cathode carbon blocks and the development of low-cost,high-performance anode materials. 展开更多
关键词 waste graphitization cathode carbon blocks defect advantage silicon/carbon anode materials hazardous waste resource util-ization
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Star-shaped Block Copolymers of Poly-2-alkyl-5,6-dihydrooxazines:Synthesis,Conformational Characteristics,Thermoresponsiveness and Complexation with Curcumin
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作者 Tatyana U.Kirila Serafim V.Rodchenko +2 位作者 Nina D.Kozina Andrey V.Tenkovtsev Alexander P.Filippov 《Chinese Journal of Polymer Science》 2026年第2期423-436,I0012,共15页
Star-shaped six-arm polymers with hexaaza[2_(6)]orthoparacyclophane core and arms of block copolymers of poly-2-ethyl-5,6-dihydrooxazine with poly-2-isopropyl-5,6-dihydrooxazine were synthesized successfully using cat... Star-shaped six-arm polymers with hexaaza[2_(6)]orthoparacyclophane core and arms of block copolymers of poly-2-ethyl-5,6-dihydrooxazine with poly-2-isopropyl-5,6-dihydrooxazine were synthesized successfully using cationic ring-opening polymerization.The ratio of blocks,the order of their attachment to the core,and arm length were varied.Conformation of synthesized stars was determined by methods of molecular hydrodynamics and optics.It has been shown that star-shaped molecules were characterized by high intramolecular density,and the arm folding increased with their lengthening.The influence of the structure of block copolymers and their molar mass on the critical micelle concentration has been established.Complexes of synthesized star-shaped block copolymers with curcumin were obtained and the efficient binding of curcumin to polymer molecules was demonstrated.The behavior of the aqueous solutions of the prepared polymer stars and their complexes with curcumin was investigated by light scattering and turbidimetry methods.The influence of the structure and molar mass of star polymers on their thermoresponsiveness and the phase separation temperatures in aqueous solutions was analyzed.A slight increase in the phase separation temperature was found on passage from polymer solutions to solutions of polymer complexes with hydrophobic curcumin. 展开更多
关键词 Thermoresponsive star-shaped polymers Block copolymer of poly-2-alkyl-5 6-dihydrooxazine Aqueous solutions Complex of polymer with curcumin Phase separation
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