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THE NUMERICAL STABILITY OF THE BLOCK θ-METHODS FOR DELAY DIFFERENTIAL EQUATIONS 被引量:1
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作者 田红炯 匡蛟勋 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2001年第1期1-8,共8页
This paper focuses on the numerical stability of the block θ methods adapted to differential equations with a delay argument. For the block θ methods, an interpolation procedure is introduced which leads to the nume... This paper focuses on the numerical stability of the block θ methods adapted to differential equations with a delay argument. For the block θ methods, an interpolation procedure is introduced which leads to the numerical processes that satisfy an important asymptotic stability condition related to the class of test problems y′(t)=ay(t)+by(t-τ) with a,b∈C, Re(a)<-|b| and τ>0. We prove that the block θ method is GP stable if and only if the method is A stable for ordinary differential equations. Furthermore, it is proved that the P and GP stability are equivalent for the block θ method. 展开更多
关键词 numerical stability block θ methods delay differential equations.
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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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乳腺癌TOMO计划设计及Block的应用方式研究
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作者 姜亚洲 杨潍铭 +1 位作者 王俭 李舰波 《生物医学工程与临床》 2026年第2期168-173,共6页
目的利用螺旋断层放射治疗(TOMO)计划系统制定乳腺癌保乳术后放射治疗计划,比较Block不同设计方法和径照功能对靶区和危及器官(OAR)剂量的影响。方法选择2024年2月至2025年2月宁波明州医院左侧乳腺癌保乳术后放射治疗女性患者15例,年龄3... 目的利用螺旋断层放射治疗(TOMO)计划系统制定乳腺癌保乳术后放射治疗计划,比较Block不同设计方法和径照功能对靶区和危及器官(OAR)剂量的影响。方法选择2024年2月至2025年2月宁波明州医院左侧乳腺癌保乳术后放射治疗女性患者15例,年龄34~66岁,平均年龄52岁;经病理明确诊断为左侧乳腺癌,其中病理分期TNMⅠ期4例,TNMⅡ期11例。基于TOMO计划系统为每例患者制定3种TOMO计划,第一种计划设计过程中应用了半挡Direction Block(DB)模式,第二种计划应用全挡Complete Block(CB)模式,第三种应用螺旋断层径照射(TD)模式制作计划;比较3种计划的剂量参数,包括靶区的适形度指数(HI)、均匀度指数(CI)、平均剂量、最大剂量;肺、心脏、健侧乳腺及脊髓等OAR剂量差异。结果在靶区剂量方面,DB组和CB组均具有较优异的均匀性和适形性,对比TD组计划差异有统计学意义(CI:0.861±0.041 vs 0.741±0.047、0.871±0.041 vs 0.741±0.047;HI:1.036±0.006 vs 1.052±0.007、1.037±0.004 vs 1.052±0.007)(P<0.05);OAR剂量方面,CB组计划的左肺V_(5)、V_(20)、D_(mean)和心脏V_(10)、V_(20)、D_(mean)均明显优于其他两组,差异均有统计学意义(P<0.05)。比较脊髓的最大剂量(D_(max)),CB组和TD组相对DB组较低,差异有统计学意义[(1.47±1.48)Gy vs(8.66±2.89)Gy、(0.46±0.13)Gy vs(8.66±2.89)Gy](P<0.05)。TD组计划的右肺V_(5),右侧乳腺平均剂量优于DB、CB两组,差异均有统计学意义[V_(5):(0.36±0.48)%vs(17.32±3.47)%、(0.36±0.48)%vs(10.66±4.10)%;右侧乳腺平均剂量:(1.53±0.88)Gy vs(6.79±1.41)Gy、(1.53±0.88)Gy vs(4.89±0.99)Gy](P<0.05)。但TD组心脏V_(10)、V_(10)较DB组、CB组计划高[V_(10):(12.39±4.39)%vs(9.72±5.03)%、(12.39±4.39)%vs(5.09±1.13)%;V_(10):(6.68±4.17)%vs(2.35±1.38)%、(6.68±4.17)%vs(1.47±0.78)%]。时间方面,CB组治疗时间最长,与DB组、TD组差异均有统计学意义[(15.18±2.31)min vs(9.68±1.43)min、(15.18±2.31)min vs(9.88±3.15)min](P<0.05)。结论针对左侧乳腺癌的3种计划比较,DB相对无明显优势,CB的优势表现在能明显降低患侧肺和心脏、脊髓的受量,TD则对保护对侧肺、乳腺能起更好的效果,但CB治疗时间较长,TD靶区适形性均匀性较差,可根据患者实际情况选择计划方式。 展开更多
关键词 螺旋断层放射治疗 block 乳腺癌 剂量学 断层径照
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Enhancing the performance of AlGaN deep-ultraviolet laser diodes without an electron blocking layer by using a thin undoped Al_(0.8)Ga_(0.2)N strip layer structure
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作者 SANG Xi-en WANG Fang +1 位作者 LIU Jun-jie LIU Yu-huai 《中国光学(中英文)》 北大核心 2026年第2期421-433,共13页
AlGaN-based deep-ultraviolet(DUV)laser diodes(LDs)face performance challenges due to elec-tron leakage and poor hole injection which is often worsened by polarization effects from conventional elec-tron blocking layer... AlGaN-based deep-ultraviolet(DUV)laser diodes(LDs)face performance challenges due to elec-tron leakage and poor hole injection which is often worsened by polarization effects from conventional elec-tron blocking layers(EBLs).To overcome these limitations,we propose an EBL-free DUV LD design incor-porating a 1-nm undoped Al_(0.8)Ga_(0.2)N thin strip layer after the last quantum barrier.Using PICS3D simula-tions,we evaluate the optical and electrical characteristics.Results show a significant increase in effective electron barrier height(from 158.2 meV to 420.7 meV)and a reduction in hole barrier height(from 149.2 meV to 62.8 meV),which enhance hole injection and reduce electron leakage.The optimized structure(LD3)achieves a 14%increase in output power,improved slope efficiency(1.85 W/A),and lower threshold current.This design also reduces the quantum confined Stark effect and forms dual hole accumulation regions,im-proving recombination efficiency. 展开更多
关键词 ALGAN deep ultraviolet laser diodes undoped thin strip structure without an electron blocking layers
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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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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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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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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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Optimal orthogonal block designs for threecomponent symmetric general blending models in mixture experiment
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作者 Jiawei Bao Yu Tang 《Statistical Theory and Related Fields》 2026年第1期117-134,共18页
In mixture experiments,the observed response is determined by the relative proportions of the components,consequently rendering the experimental region a simplex.This paper focuses primarily on the optimal designs of ... In mixture experiments,the observed response is determined by the relative proportions of the components,consequently rendering the experimental region a simplex.This paper focuses primarily on the optimal designs of mixture experiments that involve process variables.Prior research has extensively delved into optimal orthogonal block designs for some classic mixture models with process variables.Based on the framework of general blending models,this paper proposes a class of symmetric linear mixture models,which can be regarded as a generalization of many existing ones.Under the orthogonal blocking conditions,orthogonal block designs are devised through Latin squares in the presence of process variables.TheD-,A-,and E-optimality criteria are utilized to obtain optimal designs at the boundary of the simplex in the case of 3 components.As the values of the exponents change,numerically derived optimal design points are presented to illustrate the pattern of their variations,and to verify the consistency of the results with previous research on some specific symmetric general blending models. 展开更多
关键词 Mixture experiments general blending models optimal designs orthogonal Latin squares block designs
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Evaluation of bonded block models as a tool for support design in underground coal mines
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作者 Sankhaneel Sinha Gabriel Walton 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第3期1755-1767,共13页
The failure and collapse of coal pillar ribs represent a significant hazard in the mining industry,with the associated risk of fatalities and injuries anticipated to rise as mining operations advance to greater depths... The failure and collapse of coal pillar ribs represent a significant hazard in the mining industry,with the associated risk of fatalities and injuries anticipated to rise as mining operations advance to greater depths.The development of support guidelines through an enhanced understanding of pillar damage and rock–support interaction mechanisms is crucial to resolving this issue.Bonded block models(BBMs)represent a convenient tool for this purpose,as they can reasonably reproduce the rock fracturing process;however,it is not known to what extent this modeling technique can be applied to simulate pillar failure mechanisms and support interaction in anisotropic rock masses,such as coal.To bridge this gap in research,hypothetical coal pillar BBMs of different width-to-height ratios were developed and calibrated to match Mark–Bieniawski's pillar strength equation,along with a few other attributes from the literature(stress levels at the edge of pillars and the transition from brittle to strain-hardening behavior with increasing width-to-height ratio).Elongated blocks were employed to capture the anisotropic behavior of coal mass.With the reliability of the model established,a few different support patterns were evaluated to ensure that the outputs are broadly consistent with expectations.Finally,simulations of roadway development and additional mining activities were completed considering geo-mining conditions representative of underground coal mines in the USA.The good consistency between model response and expected behaviors per field observation demonstrates the potential of BBMs to be used as a support design tool. 展开更多
关键词 Bonded block model(BBM) Ground control Coal mining Anisotropic rock Support design
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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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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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Human Activity Recognition Using a CNN with an Enhanced Convolutional Block Attention Module
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作者 HU Biling TONG Yu 《Wuhan University Journal of Natural Sciences》 2026年第1期10-24,共15页
WiFi-based human activity recognition(HAR)provides a non-intrusive approach for ubiquitous monitoring;however,achieving both high accuracy and robustness simultaneously remains a significant challenge.This paper propo... WiFi-based human activity recognition(HAR)provides a non-intrusive approach for ubiquitous monitoring;however,achieving both high accuracy and robustness simultaneously remains a significant challenge.This paper proposes a Convolutional Neural Network with Enhanced Convolutional Block Attention Module(CNN-ECBAM)framework.The approach systematically converts raw Channel State Information(CSI)into pseudo-color images,effectively preserving essential signal characteristics for deep neural network processing.The core innovation is an Enhanced Convolutional Block Attention Module(ECBAM),tailored to CSI data characteristics,which integrates Efficient Channel Attention(ECA)and Multi-Scale Spatial Attention(MSSA).By employing learnable adaptive fusion weights,it achieves dynamic synergy between channel and spatial features,enabling the network to capture highly discriminative spatiotemporal patterns.The ECBAM module is integrated into a unified Convolutional Neural Network(CNN)to form the overall CNN-ECBAM model.Experimental results on the UT-HAR and NTU-Fi_HAR datasets demonstrate that CNN-ECBAM achieves competitive performance in recognition accuracy and outperforms mainstream baseline models.Specifically,it attains 99.20%accuracy on UT-HAR(surpassing ResNet-18 at 98.60%)and achieves 100%accuracy on NTU-Fi_HAR(exceeding GAF-CNN at 99.62%).These results validate the effectiveness of the proposed method for high-precision and reliable WiFi-based HAR. 展开更多
关键词 human activity recognition deep learning channel state information Enhanced Convolutional block Attention Module(ECBAM) pseudo-color images
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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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Twin-block矫治器对不同舌位下颌后缩患者上气道的改善作用
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作者 周志翀 《医师在线》 2026年第1期87-90,共4页
目的探讨静息舌位是否会影响Twin-block矫治器对下颌后缩患者上气道的扩张作用。方法选取2021年1月至2022年10月于上海市静安区牙病防治所正畸科就诊并使用Twin-block矫治器行功能矫治(以下颌前导为主)的40例患者作为研究对象。所有患... 目的探讨静息舌位是否会影响Twin-block矫治器对下颌后缩患者上气道的扩张作用。方法选取2021年1月至2022年10月于上海市静安区牙病防治所正畸科就诊并使用Twin-block矫治器行功能矫治(以下颌前导为主)的40例患者作为研究对象。所有患者均行锥形束CT(CBCT)检查,经三维重建后获取正中矢状面图像。根据舌体与上腭的位置关系分为两组:舌体与上腭紧密贴合者为舌高位组,舌体与上腭分离者为舌低位组,每组20例。观察两组患者的气道二维测量(最小横截面积)及气道三维测量(气道体积)值及变化量。结果舌低位组治疗后鼻咽段、腭咽段最小横截面积、体积及总体积均较治疗前显著增加(P<0.05);舌咽段最小横截面积、体积治疗前后比较,差异无统计学意义(P>0.05)。舌高位组治疗后鼻咽段、腭咽段最小横截面积、体积及总体积均较治疗前显著增加(P<0.05);舌咽段最小横截面积、体积治疗前后比较,差异无统计学意义(P>0.05)。组间比较显示,舌高位组腭咽段最小横截面积、体积的变化量显著大于舌低位组(P<0.05);两组鼻咽段及舌咽段最小横截面积、体积及总体积变化量比较,差异均无统计学意义(P>0.05)。结论Twin-block矫治器对下颌后缩患者上气道有扩张作用,且舌高位组患者较舌低位组患者的腭咽段气道扩张效果更为明显。 展开更多
关键词 TWIN-block矫治器 下颌后缩 气道体积 儿童
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改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形效果评价 被引量:2
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作者 卢春燕 崔雪蕾 曹培培 《上海口腔医学》 2025年第2期152-156,共5页
目的:探讨改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形的效果。方法:回顾性分析2018年1月—2022年1月如皋市中医院收治的96例安氏Ⅱ类1分类错[牙合]畸形患者资料,根据治疗方法分为试验组(52例)和对照组(44例),... 目的:探讨改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形的效果。方法:回顾性分析2018年1月—2022年1月如皋市中医院收治的96例安氏Ⅱ类1分类错[牙合]畸形患者资料,根据治疗方法分为试验组(52例)和对照组(44例),对照组采用改良Twin-block矫治器,试验组采用改良Twin-block矫治器联合微种植体支抗。比较2组矫治时间、咬合打开时间、排列整齐时间、上下牙槽座角(ANB)、下牙槽座角(SNB)、上牙槽座角(SNA)、上中切牙长轴与NA连线的夹角(U1-NA)、下中切牙长轴与NA连线的夹角(U1-NB)、上颌中切牙长轴与前颅底平面夹角(U1-SN)、下颌中切牙长轴与下颌平面的后上交角(L1-MP)、上颌唇突度(ULP)、下颌唇突度(LLP)、上下唇突点与颏前点切线和眼耳平面夹角(Z角)、菌斑指数(PLI)、牙龈指数(GI)和龈沟出血指数(SBI)。记录并发症及患者满意度。采用SPSS 24.0软件包对数据进行统计学分析。结果:试验组患者矫治时间、咬合打开时间及排列整齐时间显著少于对照组(P<0.05)。治疗后,2组ANB、U1-NA和U1-SN小于治疗前,试验组显著小于对照组(P<0.05);U1-NB、L1-MP大于治疗前,试验组显著大于对照组(P<0.05);SNB、SNA相比无显著差异(P>0.05)。治疗后,2组ULP、LLP低于治疗前,试验组显著低于对照组(P<0.05);Z角升高,试验组显著高于对照组(P<0.05);PLI低于治疗前,试验组显著低于对照组(P<0.05);GI、SBI相比无显著差异(P>0.05)。2组患者满意度相比无显著差异(P>0.05)。结论:改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形,有助于缩短矫治时间,改善颌骨及面部软组织轮廓,促进牙美学效果的恢复。 展开更多
关键词 错[牙合]畸形 安氏Ⅱ类1分类错[牙合] 改良Twin-block矫治器 微种植体支抗
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基于Chisel语言的LBlock密码算法实现
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作者 王建新 周闰泽 +1 位作者 张磊 肖超恩 《北京电子科技学院学报》 2025年第4期14-23,共10页
针对传统硬件描述语言(Verilog/VHDL)实现密码算法时代码复杂性高、开发周期长且调试困难等问题,本文提出了一种基于Chisel语言的轻量级分组密码算法LBlock的硬件实现方案。利用Chisel的高级硬件构建能力,通过模块化设计和有限状态机控... 针对传统硬件描述语言(Verilog/VHDL)实现密码算法时代码复杂性高、开发周期长且调试困难等问题,本文提出了一种基于Chisel语言的轻量级分组密码算法LBlock的硬件实现方案。利用Chisel的高级硬件构建能力,通过模块化设计和有限状态机控制,高效地实现了密钥扩展、加密和解密核心模块。通过在Xilinx ISE Design Suite 14.7上综合后,结果表明,基于Chisel的LBlock算法实现方案在逻辑资源消耗和工作频率上均表现出优势。最高工作频率达到250.197MHz,加密吞吐率为485.815 Mbps,与传统的Verilog实现相比,本设计在显著降低代码量的同时,吞吐率提升了55.7%,为资源受限环境下的密码硬件实现提供了一种更敏捷、高效的设计思路。 展开更多
关键词 Verilog HDL Lblock密码算法 分组密码 Chisel语言 有限状态机
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Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果比较 被引量:1
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作者 黄飞 陈倩 张胜男 《中国现代医学杂志》 2025年第6期6-11,共6页
目的对比Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果。方法选取2020年2月—2022年5月在彭州市中医医院就诊的安氏Ⅱ类1分类错[牙合]畸形患者72例,采用随机数字表法将其分成研究组和对照组,... 目的对比Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果。方法选取2020年2月—2022年5月在彭州市中医医院就诊的安氏Ⅱ类1分类错[牙合]畸形患者72例,采用随机数字表法将其分成研究组和对照组,每组36例。对照组接受Twin-block功能矫治器联合自锁托槽治疗,研究组接受Pass矫治器治疗。对比两组临床疗效、颌牙排齐时间、硬组织头影测量指标[上中切牙轴与蝶鞍中心-鼻根点平面夹角(U1-SN)、下中切牙轴与鼻根点-上齿槽座点连接角(U1-NA)、上齿槽座点、鼻根点及下次槽座点连接角(ANB)、蝶鞍中心、鼻根点及上齿槽座点连接角(SNA)]、软组织头影测量目标[上唇到审美平面距离(TUL-FP)、下唇H线距、下唇到审美平面距离(TLL-FP)、鼻唇角]、矫治效果及患者满意度。结果研究组总有效率高于对照组(P<0.05)。研究组上颌牙排齐时间和下颌牙排齐时间均短于对照组(P<0.05)。两组治疗前后U1-SN、ANB、SNA、SNB的差值比较,差异无统计学意义(P>0.05)。研究组治疗前后U1-NA的差值高于对照组(P<0.05)。研究组治疗前后下唇H线距、TUL-FP、鼻唇角、TLL-FP的差值高于对照组(P<0.05)。研究组治疗前后同行评估等级指数(PAR)评分的差值高于对照组(P<0.05)。研究组满意度高于对照组(P<0.05)。结论相比于Twin-block功能矫治器联合自锁托槽,Pass矫治器治疗安氏Ⅱ类1分类错[牙合]畸形患者效果确切,可提高矫治效果,改善面部侧貌美学,缩短颌牙排齐时间,且患者满意度较高。 展开更多
关键词 安氏Ⅱ类1分类错[牙合]畸形 Pass矫治器 TWIN-block功能矫治器 自锁托槽 矫正效果
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Twin-block矫治器治疗青少年骨性Ⅱ类错[牙合]畸形的效果及对上气道体积的影响
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作者 詹育香 《临床医学研究与实践》 2025年第36期50-53,共4页
目的研究Twin-block矫治器治疗青少年骨性Ⅱ类错[牙合]畸形的效果及对上气道体积的影响。方法选择2023年7月至2024年9月在本院接受治疗的40例青少年骨性Ⅱ类错[牙合]畸形患者,随机将其分为研究组(n=20,Twin-block矫治器)与对照组(n=20,... 目的研究Twin-block矫治器治疗青少年骨性Ⅱ类错[牙合]畸形的效果及对上气道体积的影响。方法选择2023年7月至2024年9月在本院接受治疗的40例青少年骨性Ⅱ类错[牙合]畸形患者,随机将其分为研究组(n=20,Twin-block矫治器)与对照组(n=20,无托槽隐形矫治器)。比较两组治疗前、后的头颅侧位片X线测量结果、上气道矢状径指标及治疗满意度。结果研究组治疗后的头颅侧位片X线测量结果[蝶鞍点-鼻根点-下牙槽座点角(SNB)、蝶鞍点-鼻根点-上牙槽座点角(SNA)、上牙槽座点-鼻根点-下牙槽座点角(ANB)]优于对照组(P<0.05)。研究组治疗后的上气道矢状径指标(鼻咽后壁至基底的矢状径、软腭后缘至咽后壁的矢状径、第一磨牙间矢状径、上颌骨后壁至中线矢状径、下颌骨后壁至中线矢状径)大于对照组(P<0.05)。研究组的治疗满意度高于对照组(P<0.05)。结论Twin-block矫治器、无托槽隐形矫治器均对青少年骨性Ⅱ类错[牙合]畸形患者有一定治疗效果,但前者能够显著改善患者的面部侧貌及上气道体积,且满意度较高。 展开更多
关键词 骨性Ⅱ类错[牙合]畸形 TWIN-block矫治器 青少年 隐形矫治器 上气道体积
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