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IoT-Based Real-Time Medical-Related Human Activity Recognition Using Skeletons and Multi-Stage Deep Learning for Healthcare 被引量:1
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作者 Subrata Kumer Paul Abu Saleh Musa Miah +3 位作者 Rakhi Rani Paul Md.EkramulHamid Jungpil Shin Md Abdur Rahim 《Computers, Materials & Continua》 2025年第8期2513-2530,共18页
The Internet of Things(IoT)and mobile technology have significantly transformed healthcare by enabling real-time monitoring and diagnosis of patients.Recognizing Medical-Related Human Activities(MRHA)is pivotal for he... The Internet of Things(IoT)and mobile technology have significantly transformed healthcare by enabling real-time monitoring and diagnosis of patients.Recognizing Medical-Related Human Activities(MRHA)is pivotal for healthcare systems,particularly for identifying actions critical to patient well-being.However,challenges such as high computational demands,low accuracy,and limited adaptability persist in Human Motion Recognition(HMR).While some studies have integrated HMR with IoT for real-time healthcare applications,limited research has focused on recognizing MRHA as essential for effective patient monitoring.This study proposes a novel HMR method tailored for MRHA detection,leveraging multi-stage deep learning techniques integrated with IoT.The approach employs EfficientNet to extract optimized spatial features from skeleton frame sequences using seven Mobile Inverted Bottleneck Convolutions(MBConv)blocks,followed by Convolutional Long Short Term Memory(ConvLSTM)to capture spatio-temporal patterns.A classification module with global average pooling,a fully connected layer,and a dropout layer generates the final predictions.The model is evaluated on the NTU RGB+D 120 and HMDB51 datasets,focusing on MRHA such as sneezing,falling,walking,sitting,etc.It achieves 94.85%accuracy for cross-subject evaluations and 96.45%for cross-view evaluations on NTU RGB+D 120,along with 89.22%accuracy on HMDB51.Additionally,the system integrates IoT capabilities using a Raspberry Pi and GSM module,delivering real-time alerts via Twilios SMS service to caregivers and patients.This scalable and efficient solution bridges the gap between HMR and IoT,advancing patient monitoring,improving healthcare outcomes,and reducing costs. 展开更多
关键词 Real-time human motion recognition(HMR) ENConvLSTM EfficientNet ConvLSTM skeleton data NTU RGB+D 120 dataset MRHA
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Hourglass-GCN for 3D Human Pose Estimation Using Skeleton Structure and View Correlation
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作者 Ange Chen Chengdong Wu Chuanjiang Leng 《Computers, Materials & Continua》 SCIE EI 2025年第1期173-191,共19页
Previous multi-view 3D human pose estimation methods neither correlate different human joints in each view nor model learnable correlations between the same joints in different views explicitly,meaning that skeleton s... Previous multi-view 3D human pose estimation methods neither correlate different human joints in each view nor model learnable correlations between the same joints in different views explicitly,meaning that skeleton structure information is not utilized and multi-view pose information is not completely fused.Moreover,existing graph convolutional operations do not consider the specificity of different joints and different views of pose information when processing skeleton graphs,making the correlation weights between nodes in the graph and their neighborhood nodes shared.Existing Graph Convolutional Networks(GCNs)cannot extract global and deeplevel skeleton structure information and view correlations efficiently.To solve these problems,pre-estimated multiview 2D poses are designed as a multi-view skeleton graph to fuse skeleton priors and view correlations explicitly to process occlusion problem,with the skeleton-edge and symmetry-edge representing the structure correlations between adjacent joints in each viewof skeleton graph and the view-edge representing the view correlations between the same joints in different views.To make graph convolution operation mine elaborate and sufficient skeleton structure information and view correlations,different correlation weights are assigned to different categories of neighborhood nodes and further assigned to each node in the graph.Based on the graph convolution operation proposed above,a Residual Graph Convolution(RGC)module is designed as the basic module to be combined with the simplified Hourglass architecture to construct the Hourglass-GCN as our 3D pose estimation network.Hourglass-GCNwith a symmetrical and concise architecture processes three scales ofmulti-viewskeleton graphs to extract local-to-global scale and shallow-to-deep level skeleton features efficiently.Experimental results on common large 3D pose dataset Human3.6M and MPI-INF-3DHP show that Hourglass-GCN outperforms some excellent methods in 3D pose estimation accuracy. 展开更多
关键词 3D human pose estimation multi-view skeleton graph elaborate graph convolution operation Hourglass-GCN
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I_(2)-DMSO mediated tetra-functionalization of enaminones for the construction of novel furo[2,3:4,5]pyrimido[1,2-b]indazole skeletons via in situ capture of ketenimine cations
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作者 You Zhou Li-Sheng Wang +6 位作者 Shuang-Gui Lei Bo-Cheng Tang Zhi-Cheng Yu Xing Li Yan-Dong Wu Kai-Lu Zheng An-Xin Wu 《Chinese Chemical Letters》 2025年第1期277-282,共6页
The first-ever synthesis of the unknown furo[2,3:4,5]pyrimido[1,2-b]indazole skeleton was demonstrated based on the undiscovered tetra-functionalization of enaminones,with simple substrates and reaction conditions.The... The first-ever synthesis of the unknown furo[2,3:4,5]pyrimido[1,2-b]indazole skeleton was demonstrated based on the undiscovered tetra-functionalization of enaminones,with simple substrates and reaction conditions.The key to realizing this process lies in the multiple trapping of the in situ generated ketenimine cation by the 3-aminoindazole,which results in the formation of four new chemical bonds and two new rings in one pot.Moreover,the products of this new reaction were found to exhibit aggregationinduced emission(AIE)without modification. 展开更多
关键词 Unknown skeleton Tetra-functionalization Ketenimine cations Aggregation-induced emission
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V_(2)CT_(X)MXene-derived ammonium vanadate with robust carbon skeleton for superior rate aqueous zinc-ion batteries
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作者 Xiaojun Wang Yizhou Zhang +4 位作者 Linwei Guo Jianwei Li Peng Wang Lei Yang Zhiming Liu 《Chinese Chemical Letters》 2025年第8期530-537,共8页
Layered ammonium vanadate has become a promising cathode material for aqueous zinc ion batteries(ZIBs)due to its small mass and large ionic radius of ammonium ions as well as the consequent large layer spacing and hig... Layered ammonium vanadate has become a promising cathode material for aqueous zinc ion batteries(ZIBs)due to its small mass and large ionic radius of ammonium ions as well as the consequent large layer spacing and high specific capacity.However,the irreversible de-ammoniation caused by N·H···O bonds damaged would impair cycle life of ZIBs and the strong electrostatic interaction between Zn^(2+)and V-O frame could slower the mobility of Zn^(2+).Furthermore,the thermal instability of ammonium vanadate also limits the use of common carbon coating modification method to solve the problem.Herein,V_(2)CT_(X)MXene was innovatively selected as a bifunctional source to in-situ derivatized(NH_(4))_(2)V_(8)O_(20)·x H_(2)O with amorphous carbon-coated(NHVO@C)via one-step hydrothermal method in relatively moderate temperature.The amorphous carbon shell derived from the V_(2)CT_(X)MXene as a conductive framework to effectively improve the diffusion kinetics of Zn^(2+)and the robust carbon skeleton could alleviate the ammonium dissolution during long-term cycling.As a result,zinc ion batteries using NHVO@C as cathode exhibit superior electrochemical performance.Moreover,the assembled foldable or high loading(10.2 mg/cm^(2))soft-packed ZIBs further demonstrates its practical application.This study provided new insights into the development of the carbon cladding process for thermally unstable materials in moderate temperatures. 展开更多
关键词 Ammonium vanadate Carbon skeleton Ammonium dissolution Superior rate performance Zinc ionbatteries
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Transformer-based skeleton extraction from all-sky images for estimating the number of auroral arcs
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作者 WANG Qian ZHANG Wei MIAO Miao 《Advances in Polar Science》 2025年第1期61-73,共13页
Studying various aurora morphology helps us understand space's physical processes and the mechanisms behind these patterns.Auroral arcs are the brightest and most prominent auroral patterns.Due to the difficulty i... Studying various aurora morphology helps us understand space's physical processes and the mechanisms behind these patterns.Auroral arcs are the brightest and most prominent auroral patterns.Due to the difficulty in precisely defining auroral shape edges,auroral arc skeleton extraction is expected as an alternative representation for studying auroral morphology,resorting skeletons extract key morphological features from complex auroral shapes.Transformer models provide a better understanding of the relationship between the overall morphology and the details when processing image data,so we proposed a Transformer-based method for auroral arc skeleton extraction.Combined with ridge-guided annotation on all-sky images,a Transformer-based skeleton extractor is trained and used to estimate the number of auroral arcs.Experiments demonstrate that the Transformer-based model can more effectively capture structural information and local details of auroral arcs,which is suitable for complex auroral morphologies. 展开更多
关键词 AURORA all-sky image skeleton extraction
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Evaluating the feasibility of copper-based skeletons in lithium metal batteries operated at subzero temperature
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作者 Yiyu Huang Ouwei Sheng +6 位作者 Qingyue Han Hongyan Li Lei Sun Qimeng Sheng Lijing Yan Zeheng Li Chengbin Jin 《Journal of Energy Chemistry》 2025年第5期765-772,共8页
The next-generation lithium(Li)metal batteries suffer severe low-temperature capacity degradation,appealing for expeditions on solutions.Herein,the feasibility of copper-based skeletons(i.e.,2D Cu foil,3D Cu mesh,and ... The next-generation lithium(Li)metal batteries suffer severe low-temperature capacity degradation,appealing for expeditions on solutions.Herein,the feasibility of copper-based skeletons(i.e.,2D Cu foil,3D Cu mesh,and CuZn mesh)frequently adopted in the stabilization of Li are evaluated at low temperatures.Li growth patterns and stripping behaviors on different skeletons and at different temperatures uncover the dendrite-free and dead-Li-less Li deposition/dissolution on CuZn mesh.Three-electrode impedance indicates the dynamic advantages of CuZn mesh,driving fast Li^(+)crossing through solidelectrolyte-interphase and charge transfer process.Notably,CuZn mesh enables the stable operation and fast charging(1.8 mA cm^(-2))of Li||LiFePO_(4)cells for over 120 cycles at-10℃ with a superior capacity retention of 88%.The success of CuZn mesh can be translated into lower temperature(-20℃)and 1.0-Ah-level pouch cells.This work provides fundamentals on improving low-temperature battery performances by skeletons with regulated spatial structure and lithiophilicity. 展开更多
关键词 Low temperature Lithium metal battery Copper-based skeleton
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MXene Hollow Spheres Supported by a C–Co Exoskeleton Grow MWCNTs for Efficient Microwave Absorption 被引量:4
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作者 Ze Wu Xiuli Tan +4 位作者 Jianqiao Wang Youqiang Xing Peng Huang Bingjue Li Lei Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期76-94,共19页
High-performance microwave absorption(MA) materials must be studied immediately since electromagnetic pollution has become a problem that cannot be disregarded. A straightforward composite material, comprising hollow ... High-performance microwave absorption(MA) materials must be studied immediately since electromagnetic pollution has become a problem that cannot be disregarded. A straightforward composite material, comprising hollow MXene spheres loaded with C–Co frameworks, was prepared to develop multiwalled carbon nanotubes(MWCNTs). A high impedance and suitable morphology were guaranteed by the C–Co exoskeleton, the attenuation ability was provided by the MWCNTs endoskeleton, and the material performance was greatly enhanced by the layered core–shell structure. When the thickness was only 2.04 mm, the effective absorption bandwidth was 5.67 GHz, and the minimum reflection loss(RLmin) was-70.70 d B. At a thickness of 1.861 mm, the sample calcined at 700 ℃ had a RLmin of-63.25 d B. All samples performed well with a reduced filler ratio of 15 wt%. This paper provides a method for making lightweight core–shell composite MA materials with magnetoelectric synergy. 展开更多
关键词 MXene C-Co skeleton MWCNTS Microwave absorption
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Ageing-related bone and immunity changes:insights into the complex interplay between the skeleton and the immune system 被引量:2
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作者 Bobin Mi Yuan Xiong +6 位作者 Samuel Knoedler Michael Alfertshofer Adriana C.Panayi Haixing Wang Sien Lin Gang Li Guohui Liu 《Bone Research》 SCIE CAS CSCD 2024年第3期502-516,共15页
Ageing as a natural irreversible process inherently results in the functional deterioration of numerous organ systems and tissues,including the skeletal and immune systems.Recent studies have elucidated the intricate ... Ageing as a natural irreversible process inherently results in the functional deterioration of numerous organ systems and tissues,including the skeletal and immune systems.Recent studies have elucidated the intricate bidirectional interactions between these two systems. 展开更多
关键词 skeleton INSIGHT IRREVERSIBLE
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Double-layered skeleton of Li alloy anchored on 3D metal foam enabling ultralong lifespan of Li anode under high rate 被引量:1
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作者 Chaohui Wei Zeyu Yao +7 位作者 Jin Ruan Zhicui Song Aijun Zhou Yingze Song Donghuang Wang Jicheng Jiang Xin Wang Jingze Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第3期479-485,共7页
The high specific capacity and low negative electrochemical potential of lithium metal anodes(LMAs),may allow the energy density threshold of Li metal batteries(LMBs)to be pushed higher.However,the existing detrimenta... The high specific capacity and low negative electrochemical potential of lithium metal anodes(LMAs),may allow the energy density threshold of Li metal batteries(LMBs)to be pushed higher.However,the existing detrimental issues,such as dendritic growth and volume expansion,have hindered the practical implementation of LMBs.Introducing three-dimensional frameworks(e.g.,copper and nickel foam),have been regarded as one of the fundamental strategies to reduce the local current density,aiming to extend the Sand'time.Nevertheless,the local environment far from the skeleton is almost the same as the typical plane Li,due to macroporous space of metal foam.Herein,we built a double-layered 3D current collector of Li alloy anchored on the metal foam,with micropores interconnected macropores,via a viable thermal infiltration and cooling strategy.Due to the excellent electronic and ionic conductivity coupled with favorable lithiophilicity,the Li alloy can effectively reduce the nucleation barrier and enhance the Li^(+)transportation rate,while the metal foam can role as the primary promotor to enlarge the surface area and buffer the dimensional variation.Synergistically,the Li composite anode with hierarchical structure of primary and secondary scaffolds realized the even deposition behavior and minimum volume expansion,outputting preeminent prolonged cycling performances under high rate. 展开更多
关键词 Double-layered skeleton Li alloy 3D Metal foam Ultralong lifespan Lithium metal batteries High rate
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Terpene extract from the stem of Celastrus orbiculatus inhibits actin cytoskeleton remodelling in gastric cancer cells by regulating the protein interaction between PTBP1 and ACTN4 被引量:1
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作者 Zewen Chu Miao Zhu +6 位作者 Yuanyuan Luo Yaqi Hu Xinyi Feng Jiacheng Shen Haibo Wang Masataka Sunagawa Yanqing Liu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第8期1158-1175,共18页
Adjuvant chemoradiotherapy,molecular targeted therapy,and immunotherapy are frequently employed to extend the survival of patients with advanced gastric cancer(GC).However,most of these treatments have toxic side effe... Adjuvant chemoradiotherapy,molecular targeted therapy,and immunotherapy are frequently employed to extend the survival of patients with advanced gastric cancer(GC).However,most of these treatments have toxic side effects,drug resistance,and limited improvements in survival and quality of life.Therefore,it is crucial to discover and develop new medications targeting GC that are highly effective and have minimal toxicity.In previous studies,the total terpene extract from the stem of Celastrus orbiculatus demonstrated anti-GC activity;however,the specific mechanism was unclear.Our research utilising coimmunoprecipitation-mass spectrometry(Co-IP-MS),polypyrimidine tract binding protein 1(ptbp1)clustered regularly interspaced short palindromic repeat-associated protein 9(Cas9)-knockout(KO)mouse model,tissue microarray,and functional experiments suggests that alpha actinin-4(ACTN4)could be a significant biomarker of GC.PTBP1 influences actin cytoskeleton restructuring in GC cells by interacting with ACTN4.Celastrus orbiculatus stem extract(COE)may directly target ACTN4 and affect the interaction between PTBP1 and ACTN4,thereby exerting anti-GC effects. 展开更多
关键词 Traditional Chinese medicine Polypyrimidine tract binding protein 1 Alpha actinin-4 Gastric cancer Actin skeleton remodelling
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Rational design of carbon skeleton interfaces for highly reversible sodium metal battery anodes
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作者 Fenqiang Luo Taiyu Lyu +5 位作者 Jie Liu Peiwan Guo Junkai Chen Xiaoshan Feng Dechao Wang Zhifeng Zheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期404-413,共10页
Sodium metal batteries(SMBs)have attracted increasing attention over time due to their abundance of sodium resources and low cost.However,the widespread application of SMBs as a viable technology remains a great chall... Sodium metal batteries(SMBs)have attracted increasing attention over time due to their abundance of sodium resources and low cost.However,the widespread application of SMBs as a viable technology remains a great challenge,such as uneven metallic deposition and dendrite formation during cycling.Carbon skeletons as sodiophilic hosts can alleviate the dendrite formation during the plating/stripping.For the carbon skeleton,how to rationalize the design sodiophilic interfaces between the sodium metal and carbon species remains key to developing desirable Na anodes.Herein,we fabricated four kinds of structural features for carbon skeletons using conventional calcination and flash Joule heating.The roles of conductivity,defects,oxygen content,and the distribution of graphite for the deposition of metallic sodium were discussed in detail.Based on interface engineering,the J1600 electrode,which has abundant Na-C species on its surface,showed the highest sodiophilic.There are uniform and rich F-Na species distributed in the inner solid electrolyte interface layer.This study investigated the different Na-deposition behavior in carbon hosts with distinct graphitic arrangements to pave the way for designing and optimizing advanced electrode materials. 展开更多
关键词 Carbon skeleton Graphited structure Deposition mechanism Sodiummetal batteries
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Vacancy defect MoSeTe embedded in N and F co-doped carbon skeleton for high performance sodium ion batteries and hybrid capacitors
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作者 Dehui Yang Wentao Guo +6 位作者 Fei Guo Jiaming Zhu Gang Wang Hui Wang Guanghui Yuan Shenghua Ma Beibei Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期652-664,I0014,共14页
Sodium-ion batteries(SIBs) and hybrid capacitors(SIHCs) have garnered significant attention in energy storage due to their inherent advantages,including high energy density,cost-effectiveness,and enhanced safety.Howev... Sodium-ion batteries(SIBs) and hybrid capacitors(SIHCs) have garnered significant attention in energy storage due to their inherent advantages,including high energy density,cost-effectiveness,and enhanced safety.However,developing high-performance anode materials to improve sodium storage performa nce still remains a major challenge.Here,a facile one-pot method has been developed to fabricate a hybrid of MoSeTe nanosheets implanted within the N,F co-doped honeycomb carbon skeleton(MoSeTe/N,F@C).Experimental results demonstrate that the incorporation of large-sized Te atoms into MoSeTe nanosheets enlarges the layer spacing and creates abundant anion vacancies,which effectively facilitate the insertion/extraction of Na^(+) and provide numerous ion adsorption sites for rapid surface capacitive behavior.Additionally,the heteroatoms N,F co-doped honeycomb carbon skeleton with a highly conductive network can restrain the volume expansion and boost reaction kinetics within the electrode.As anticipated,the MoSeTe/N,F@C anode exhibits high reversible capacities along with exceptional cycle stability.When coupled with Na_(3)V_(2)(PO_(4))_(3)@C(NVPF@C) to form SIB full cells,the anode delivers a reversible specific capacity of 126 mA h g^(-1) after 100 cycles at 0.1 A g^(-1).Furthermore,when combined with AC to form SIHC full cells,the anode demonstrates excellent cycling stability with a reversible specific capacity of50 mA h g^(-1) keeping over 3700 cycles at 1.0 A g^(-1).In situ XRD,ex situ TEM characterization,and theoretical calculations(DFT) further confirm the reversibility of sodium storage in MoSeTe/N,F@C anode materials during electrochemical reactions,highlighting their potential for widespread practical application.This work provides new insights into the promising utilization of advanced transition metal dichalcogenides as anode materials for Na^(+)-based energy storage devices. 展开更多
关键词 MoSeTe N F co-doped honeycomb carbon skeleton Sodium-ion batteries Sodium-ion hybrid capacitor
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Cobalt selenide confined in nitrogen-doped carbon skeleton as high-rated capability anode for sodium-ion batteries
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作者 Jiang-Li Luo Xin-Yu Wang +5 位作者 Run-Lin Liu Yu-Han Zeng Huai-Qiang Gu Lei Tan Xin Du Dan Li 《Rare Metals》 CSCD 2024年第12期6742-6750,共9页
Cobalt selenide(CoSe_(2))has gained extensive interests due to its high redox reactivity and theoretical capacity.However,its substantial volumetric change during reaction leads to structural instability and consequen... Cobalt selenide(CoSe_(2))has gained extensive interests due to its high redox reactivity and theoretical capacity.However,its substantial volumetric change during reaction leads to structural instability and consequently inferior cycling performance.In this study,a Co-zeolitic imidazolate framework was synthesized as the precursor via the solvotihermal method and then subjected to a selenizationtreatment to transform into CoSe_(2)nanoparticles. 展开更多
关键词 capacity skeleton CONFINED
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磷石膏基团粒调控固化淤泥的物理力学性能 被引量:1
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作者 谈云志 吴仙桥 +3 位作者 吴军 明华军 王冲 肖宇 《岩土力学》 北大核心 2025年第6期1667-1677,共11页
淤泥颗粒细腻、含水率高,固化强度主要由胶结强度提供,摩擦强度不高。以磷石膏、矿渣和生石灰为原料,制备磷石膏基团粒,再协同水泥固化淤泥,评价了固化淤泥的物理力学性能。结果表明,磷石膏基团粒的吸水率为13.4%,可以局部分离淤泥中的... 淤泥颗粒细腻、含水率高,固化强度主要由胶结强度提供,摩擦强度不高。以磷石膏、矿渣和生石灰为原料,制备磷石膏基团粒,再协同水泥固化淤泥,评价了固化淤泥的物理力学性能。结果表明,磷石膏基团粒的吸水率为13.4%,可以局部分离淤泥中的自由水,提升水泥的固化效果;压实成团后,磷石膏中的可溶磷(氟)浸出浓度均显著低于原状磷石膏的对应浸出浓度,且均低于地表III类水的排放标准(P浸出浓度≤0.2 mg/L,F浸出浓度≤1.0 mg/L),满足环保要求;磷石膏基团粒(粒径d≤5 mm)均匀分布于淤泥中,发挥骨架效应,明显提升固化淤泥强度,提升率达到22.3%,强度超过1 MPa。究其原因,团粒中的磷石膏−矿渣粉−石灰反应生成水化硅酸钙(C-S-H)凝胶和针状钙矾石,C-S-H凝胶和针状钙矾石相互交织形成空间网状结构,填补了磷石膏基团粒内部孔隙和团粒−淤泥交界过渡区的孔隙,既固定了可溶磷和氟,又提升了团粒−淤泥界面过渡区的搭接能力。研究结论既为磷石膏综合利用提供参考依据,也为淤泥固化提供新方法。 展开更多
关键词 固化淤泥 磷石膏基团粒 骨架效应 界面胶结
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流动胶浆沥青混合料(FMA)理论与设计方法 被引量:2
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作者 吴旷怀 吴传海 +6 位作者 聂桂海 蔡旭 许新权 郑钰祺 黄文柯 王志祥 黄建栋 《中国公路学报》 北大核心 2025年第2期102-113,共12页
探讨了热拌沥青混合料(Hot Mix Asphalt,HMA)组成特性与路用性能的内在联系,以及现行HMA成型或施工过程中胶浆可塑不析漏这一共同基石对沥青混合料设计、施工及沥青路面性能的影响。基于胶浆流动这一理论创新和胶浆流动填充骨架空隙的原... 探讨了热拌沥青混合料(Hot Mix Asphalt,HMA)组成特性与路用性能的内在联系,以及现行HMA成型或施工过程中胶浆可塑不析漏这一共同基石对沥青混合料设计、施工及沥青路面性能的影响。基于胶浆流动这一理论创新和胶浆流动填充骨架空隙的原理,提出了流动胶浆沥青混合料(Fluid Mastic Asphalt,FMA)理论框架及其胶浆流动填充(Mastic Flow for Filling Method,MaFF)设计方法,探索了FMA的多种成型工艺。设计并成型了多种典型FMA混合料,进行了路用性能评价和验证。结果表明:由于胶浆流动,FMA更易于形成紧密骨架且内部空隙率接近于0,形成新型的骨架-超密实结构。从而FMA能够在确保抗车辙的前提下,避免沥青路面水损害,提升沥青路面抵抗疲劳和反射开裂的能力以及抗老化性能。此外,胶浆流动使得FMA的表面构造能够灵活设计,从而实现路面抗滑性能设计和抗滑耐久设计。FMA胶浆用量需要有所增加以使得胶浆能够流动,采用现行工艺时施工难度可能增大,但FMA有望大幅度提升沥青混合料的性能,此外,胶浆流动使得FMA的表面构造能够灵活设计,从而实现路面抗滑性能设计和抗滑耐久设计。FMA胶浆用量需要有所增加以使得胶浆能够流动,采用现行工艺时施工难度可能增大,但FMA有望大幅度提升沥青混合料的性能,从而使FMA能够在确保抗车辙的前提下,避免沥青路面水损害,提升沥青路面抵抗疲劳、反射开裂的能力以及抗老化性能。FMA理论及其MaFF法突破了现行的HMA理论体系和设计框架,能够大幅提升路面耐久性,降低寿命周期成本和资源消耗,为沥青路面行业带来深远影响,值得进一步深入研究。 展开更多
关键词 路面工程 流动胶浆沥青混合料(FMA) 胶浆流动填充设计方法 骨架-超密实结构 耐久性
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考虑环境温度的钢管约束混凝土柱拟静力试验研究 被引量:1
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作者 王力 潘启仁 +3 位作者 顾皓玮 胡琦 虞庐松 李子奇 《振动与冲击》 北大核心 2025年第5期155-168,共14页
为研究不同环境温度下钢管约束混凝土(steel tube confined concrete,STCC)柱的抗震性能,开展了9根不同温度工况下的STCC柱拟静力试验,分析各试件在不同温度下的试验现象及破坏形态,揭示环境温度对STCC柱抗震性能的影响机理。针对现行S... 为研究不同环境温度下钢管约束混凝土(steel tube confined concrete,STCC)柱的抗震性能,开展了9根不同温度工况下的STCC柱拟静力试验,分析各试件在不同温度下的试验现象及破坏形态,揭示环境温度对STCC柱抗震性能的影响机理。针对现行STCC骨架曲线模型计算方法中未考虑环境影响的不足,基于试验和有限元计算结果,提出了考虑环境温度影响的STCC理论骨架曲线特征点温度修正计算公式。结果表明:环境温度变化引起的STCC材料变异和温度附加套箍效应对试件水平承载力和延性影响显著,环境高温(60℃)会使核心混凝土强度降低,且在钢-混凝土界面易发生脱粘脱空,导致试件承载力和延性分别下降9.4%、12.2%;低温(-40℃)工况下,由于核心混凝土强度提高,同时外壁钢管对核心混凝土的约束作用加强,使试件承载力提升18.7%,但其延性最大降低47.2%,对抗震产生不利影响;所提考虑环境温度影响的STCC理论骨架曲线具有较好的可靠性和精度,可为高寒大温差地区该类型结构的抗震设计提供必要理论依据。 展开更多
关键词 钢管约束混凝土(STCC) 环境温度 拟静力试验 理论骨架曲线 温度附加套箍效应
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中华美学史的性质及内在逻辑论 被引量:1
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作者 陈望衡 《河北学刊》 北大核心 2025年第1期55-66,共12页
对于中华美学史的性质及内在逻辑,可以从五个方面展开论述:第一,中华美学的民族性。中华美学是中华民族的美学,中华民族文化以汉文化为灵魂,却绝不只是汉族文化,它熔铸了生活在中国大地上的诸多民族的文化精神,突出体现了中华民族共同... 对于中华美学史的性质及内在逻辑,可以从五个方面展开论述:第一,中华美学的民族性。中华美学是中华民族的美学,中华民族文化以汉文化为灵魂,却绝不只是汉族文化,它熔铸了生活在中国大地上的诸多民族的文化精神,突出体现了中华民族共同的理念、精神、传统。第二,中华美学的国家性。中华美学的国家性奠基于周朝,周朝的礼乐文化既是政治文化,又是审美文化。中华文化中的主要学派儒、道、墨等的美学思想均见出鲜明的国家性。第三,中华美学的文化骨架。其根植于中华文化的三大流派:儒、道、释。儒家美学重社会,道家美学重自然,释家美学重心性。三者相对而又互补,共同构成中华美学的文化骨架。第四,中华美学的诗性品位。《诗经》《楚辞》和唐诗的巨大影响构建了中华美学的诗性品位。第五,中华美学的基本精神。其体现在对审美本体论的认识上,道家的美在自然与儒家的美在文明的统一,构成了中华美学的基本精神。 展开更多
关键词 中华美学 民族性 国家性 文化骨架 诗性品位 基本精神
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融合时空注意力的改进ST-GCN人体动作识别方法研究 被引量:1
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作者 雷建云 梁钧 +2 位作者 夏梦 张慧丽 田祚汉 《中南民族大学学报(自然科学版)》 2025年第4期526-535,共10页
针对现有的人体骨架动作识别算法不能充分发掘运动的时空特征问题,提出了一种基于融合时空注意力的改进图卷积网络模型.该模型包含空间注意力机制和时间注意力机制,利用时空注意力机制从时间和空间两个维度分别提取动作的全局时空特征.... 针对现有的人体骨架动作识别算法不能充分发掘运动的时空特征问题,提出了一种基于融合时空注意力的改进图卷积网络模型.该模型包含空间注意力机制和时间注意力机制,利用时空注意力机制从时间和空间两个维度分别提取动作的全局时空特征.将这二者融合到统一的时空图卷积网络(ST-GCN)框架中,实现了端到端的训练.在Kinetics和NTU RGB+D两个公开数据集的对比实验证明:改进模型在NTU-RGB+D数据集上的CS标准下取得了82.37%的Top-1精度,在CV标准下取得89.84%的Top-1精度,相比原来的ST-GCN算法,分别提升0.87%的Top-1精度和1.54%的Top-5精度.在Kinetics数据集上,改进模型取得了31.78%的精度,与ST-GCN相比提高了1.08%.由此验证了改进方法的有效性. 展开更多
关键词 图卷积网络 骨架数据 动作识别 时空注意力
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基于通道注意力机制增强DGNN的外骨骼机器人步态相位预测 被引量:1
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作者 颜建军 许赢家 +2 位作者 林越 金理 江金林 《华东理工大学学报(自然科学版)》 北大核心 2025年第1期110-118,共9页
利用一种基于通道注意力机制增强的有向图神经网络(Channel Attention Enhanced Directed Graph Neural Network,CA-DGNN)的外骨骼机器人步态相位预测方法,提高了步态相位预测的准确性和可靠性。首先,研制了人体下肢姿态信息采集装置,... 利用一种基于通道注意力机制增强的有向图神经网络(Channel Attention Enhanced Directed Graph Neural Network,CA-DGNN)的外骨骼机器人步态相位预测方法,提高了步态相位预测的准确性和可靠性。首先,研制了人体下肢姿态信息采集装置,采集人体下肢的行走步态数据并构建人体下肢的骨架模型;之后,建立了基于CA-DGNN步态相位的预测模型,提取人体步态相位的运动特征,并基于当前时刻数据预测未来时刻的步态相位;最后,探讨了滑动窗口大小对算法性能的影响。本文提高了外骨骼机器人步态相位预测的准确性和鲁棒性,为此方向研究提供了一种新的思路和方法。 展开更多
关键词 步态相位预测 惯性传感器 骨架 时空图卷积网络 通道注意力机制
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螺栓连接预制装配式剪力墙抗剪承载力 被引量:2
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作者 姜绍飞 卞智海 +2 位作者 宋华霖 赵剑 连晟航 《哈尔滨工程大学学报》 北大核心 2025年第6期1159-1168,共10页
为探究剪跨比、轴压比和配箍率等参数对螺栓连接预制装配式剪力墙的抗剪性能影响,本文开展了抗剪承载力参数分析和计算方法研究。对3片BASW进行拟静力试验,建立了精细化仿真模型并进行了验证;开展了剪跨比、轴压比和配箍率对螺栓连接预... 为探究剪跨比、轴压比和配箍率等参数对螺栓连接预制装配式剪力墙的抗剪性能影响,本文开展了抗剪承载力参数分析和计算方法研究。对3片BASW进行拟静力试验,建立了精细化仿真模型并进行了验证;开展了剪跨比、轴压比和配箍率对螺栓连接预制装配式剪力墙的抗剪性能参数分析;基于螺栓连接预制装配式剪力墙工作机理推导了抗剪承载力计算公式,并与已有文献和现行规范进行对比。研究发现:剪跨比越小或轴压比越大,抗剪承载力越大,延性变差;配箍率越大,承载力、刚度越大,提高幅度趋于减弱。本文提出的承载力公式的计算值与试验结果吻合良好,研究表明螺栓连接预制装配式剪力墙具有良好的抗剪性能,推导的抗剪承载力公式具有较好的适用性。 展开更多
关键词 装配式剪力墙 螺栓连接 数值模拟 剪跨比、轴压比、配箍率、骨架曲线 抗剪承载力公式
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