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AI-driven integration of multi-omics and multimodal data for precision medicine
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作者 Heng-Rui Liu 《Medical Data Mining》 2026年第1期1-2,共2页
High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging ... High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging foundation models and multimodal learning frameworks are enabling scalable and transferable representations of cellular states,while advances in interpretability and real-world data integration are bridging the gap between discovery and clinical application.This paper outlines a concise roadmap for AI-driven,transcriptome-centered multi-omics integration in precision medicine(Figure 1). 展开更多
关键词 high throughput transcriptomics multi omics single cell multimodal learning frameworks foundation models omics data modalitiesemerging ai driven precision medicine
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Intelligent integration and advancement of multi-organ-on-a-chip
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作者 Chen-Xi Song Lu Huang 《Biomedical Engineering Communications》 2026年第1期1-3,共3页
Multi-organ-on-a-chip(MOOC)technology represents a pivotal direction in the organ-on-a-chip field,seeking to emulate the complex interactions of multiple human organs in vitro through microfluidic systems.This technol... Multi-organ-on-a-chip(MOOC)technology represents a pivotal direction in the organ-on-a-chip field,seeking to emulate the complex interactions of multiple human organs in vitro through microfluidic systems.This technology overcomes the limitations of traditional single-organ models,providing a novel platform for investigating complex disease mechanisms and evaluating drug efficacy and toxicity.Although it demonstrates broad application prospects,its development still faces critical bottlenecks,including inadequate physiological coupling between organs,short functional maintenance durations,and limited real-time monitoring capabilities.Contemporary research is advancing along three key directions,including functional coupling,sensor integration,and full-process automation systems,to propel the technology toward enhanced levels of physiological relevance and predictive accuracy. 展开更多
关键词 investigating complex disease mechanisms emulate complex interactions multiple human organs vitro sensor integration intelligent integration predictive accuracy physiological coupling multi organ chip microfluidic systemsthis
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Role of Multi-Electron and Multi-Orbital Effects in High-Order Harmonic Generation of Benzonitrile Molecules
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作者 Man Xing Jun Wang +1 位作者 Xi Zhao Shushan Zhou 《Chinese Physics Letters》 2025年第4期43-49,共7页
Multi-electron and multi-orbital effects play a crucial role in the interaction of strong laser fields with complex molecules.Here,multi-electron effects encompass not only electron-electron Coulomb interactions and e... Multi-electron and multi-orbital effects play a crucial role in the interaction of strong laser fields with complex molecules.Here,multi-electron effects encompass not only electron-electron Coulomb interactions and exchangecorrelation effects but also the interference between the dynamics of different electron wave packets. 展开更多
关键词 electron wave packets multi electron effects multi orbital effects high order harmonic generation benzonitrile molecules exchangecorrelation effects complex moleculesheremulti electron interference dynamics
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“大数据、大模型、大计算”全新范式与舆情精准研判:理论和Multi-Agent实证两个向度的探索 被引量:1
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作者 丁晓蔚 戚庆燕 刘梓航 《传媒观察》 2025年第2期28-42,共15页
本文探讨了“大数据、大模型、大计算”全新范式在舆情精准研判中的相关理论和应用实证。理论部分论述了该范式的概念和所涉关系,分析了其与Multi-Agent多智能体系统之间的联系。实证部分基于此范式在舆情研判中的应用案例,提出Multi-Ag... 本文探讨了“大数据、大模型、大计算”全新范式在舆情精准研判中的相关理论和应用实证。理论部分论述了该范式的概念和所涉关系,分析了其与Multi-Agent多智能体系统之间的联系。实证部分基于此范式在舆情研判中的应用案例,提出Multi-Agent多智能体协作驱动的舆情分析框架,构建全新的舆情研判流程,能有效应对动态变化的舆情环境。采用Multi-Agent对热点事件是否上热搜进行预测和检验,并与传统大模型和BERT模型进行对比分析。研究表明:Multi-Agent在应对涉及公众情感共鸣和社会性广泛事件时具有显著优势,能通过多角度的综合评估提升预测精度和鲁棒性。通过实证研究验证了Multi-Agent在舆情监测中的重要价值,为未来舆情精准研判提供了新的技术路径。 展开更多
关键词 “大数据、大模型、大计算”全新范式 multi-Agent多智能体系统 舆情精准研判
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Multi-Scale Feature Fusion and Advanced Representation Learning for Multi Label Image Classification
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作者 Naikang Zhong Xiao Lin +1 位作者 Wen Du Jin Shi 《Computers, Materials & Continua》 2025年第3期5285-5306,共22页
Multi-label image classification is a challenging task due to the diverse sizes and complex backgrounds of objects in images.Obtaining class-specific precise representations at different scales is a key aspect of feat... Multi-label image classification is a challenging task due to the diverse sizes and complex backgrounds of objects in images.Obtaining class-specific precise representations at different scales is a key aspect of feature representation.However,existing methods often rely on the single-scale deep feature,neglecting shallow and deeper layer features,which poses challenges when predicting objects of varying scales within the same image.Although some studies have explored multi-scale features,they rarely address the flow of information between scales or efficiently obtain class-specific precise representations for features at different scales.To address these issues,we propose a two-stage,three-branch Transformer-based framework.The first stage incorporates multi-scale image feature extraction and hierarchical scale attention.This design enables the model to consider objects at various scales while enhancing the flow of information across different feature scales,improving the model’s generalization to diverse object scales.The second stage includes a global feature enhancement module and a region selection module.The global feature enhancement module strengthens interconnections between different image regions,mitigating the issue of incomplete represen-tations,while the region selection module models the cross-modal relationships between image features and labels.Together,these components enable the efficient acquisition of class-specific precise feature representations.Extensive experiments on public datasets,including COCO2014,VOC2007,and VOC2012,demonstrate the effectiveness of our proposed method.Our approach achieves consistent performance gains of 0.3%,0.4%,and 0.2%over state-of-the-art methods on the three datasets,respectively.These results validate the reliability and superiority of our approach for multi-label image classification. 展开更多
关键词 Image classification multi-LABEL multi scale attention mechanisms feature fusion
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Low-light image enhancement based on multi-illumination estimation and multi-scale fusion
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作者 ZHANG Xin'ai GAO Jing +1 位作者 NIE Kaiming LUO Tao 《Optoelectronics Letters》 2025年第6期362-369,共8页
To improve image quality under low illumination conditions,a novel low-light image enhancement method is proposed in this paper based on multi-illumination estimation and multi-scale fusion(MIMS).Firstly,the illuminat... To improve image quality under low illumination conditions,a novel low-light image enhancement method is proposed in this paper based on multi-illumination estimation and multi-scale fusion(MIMS).Firstly,the illumination is processed by contrast-limited adaptive histogram equalization(CLAHE),adaptive complementary gamma function(ACG),and adaptive detail preserving S-curve(ADPS),respectively,to obtain three components.Then,the fusion-relevant features,exposure,and color contrast are selected as the weight maps.Subsequently,these components and weight maps are fused through multi-scale to generate enhanced illumination.Finally,the enhanced images are obtained by multiplying the enhanced illumination and reflectance.Compared with existing approaches,this proposed method achieves an average increase of 0.81%and 2.89%in the structural similarity index measurement(SSIM)and peak signal-to-noise ratio(PSNR),and a decrease of 6.17%and 32.61%in the natural image quality evaluator(NIQE)and gradient magnitude similarity deviation(GMSD),respectively. 展开更多
关键词 adaptive detail preserving s curve contrast limited adaptive histogram equalization adaptive complementary gamma function low light image enhancement equalization clahe adaptive complementary gamma function acg multi scale fusion weight maps multi illumination estimation
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Multi-brand strategy fuels Luolai's 45.97% gross margin in Q1
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作者 Qiu Shuchen 《China Textile》 2025年第3期34-37,共4页
Recently,Luolai Group released its Q12025 quarterly report.As a leading Chinese home textile enterprise listed on the Shenzhen Stock Exchange in 2009,the company covers the research,design,production,and sales of home... Recently,Luolai Group released its Q12025 quarterly report.As a leading Chinese home textile enterprise listed on the Shenzhen Stock Exchange in 2009,the company covers the research,design,production,and sales of home textile products,and has multiple brands covering different consumer markets.It has expanded its online and offline comprehensive multichannel sales system and is committed to creating a win-win home furnishings and textile industry ecosystem. 展开更多
关键词 multichannel sales ECOSYSTEM home furnishings gross margin home textile multi brand strategy quarterly report
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Multi-chip multi-phase DC−DC converters for AI power:a ring,a chain,or a net,independent or master-slave?
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作者 Yan Lu Zhiguo Tong +3 位作者 Jiacheng Yang Zhewen Yu Mo Huang Xiangyu Mao 《Journal of Semiconductors》 2025年第7期2-4,共3页
Motivation.As artificial intelligence(AI)workloads escalate exponentially,ultra-thin,high-efficiency voltage regulator modules(VRMs)with exceptional power density become essential for backside-mounted configurations[1... Motivation.As artificial intelligence(AI)workloads escalate exponentially,ultra-thin,high-efficiency voltage regulator modules(VRMs)with exceptional power density become essential for backside-mounted configurations[1].Thus,highdensity multiphase DC−DC converters are pivotal for implementing vertical power delivery(VPD)architectures in XPU platforms.Strategically positioning these converters beneath processors and maximizing spatial utilization enables core rail currents exceeding 2 kA while significantly reducing the power distribution network(PDN)losses compared to conventional solutions.The VPD configuration elevates system-level energy efficiency with>100 W power saving per processor,yielding megawatt-scale savings in a datacenter that uses~100000 processors.The synergy of 48 V power conversion architectures and advanced packaging techniques enables the industry’s commitment to balancing computational demands with CO_(2)emission reduction and environmental sustainability. 展开更多
关键词 maximizing spatial utilization vertical power delivery vpd architectures multi chip AI power ring topology xpu platformsstrategically multiphase dc dc converters core rail currents
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MSL-Net:a lightweight apple leaf disease detection model based on multi-scale feature fusion
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作者 YANG Kangyi YAN Chunman 《Optoelectronics Letters》 2025年第12期745-752,共8页
Aiming at the problem of low detection accuracy due to the different scale sizes of apple leaf disease spots and their similarity to the background,this paper proposes a multi-scale lightweight network(MSL-Net).Firstl... Aiming at the problem of low detection accuracy due to the different scale sizes of apple leaf disease spots and their similarity to the background,this paper proposes a multi-scale lightweight network(MSL-Net).Firstly,a multiplexed aggregated feature extraction network is proposed using residual bottleneck block(RES-Bottleneck)and middle partial-convolution(MP-Conv)to capture multi-scale spatial features and enhance focus on disease features for better differentiation between disease targets and background information.Secondly,a lightweight feature fusion network is designed using scale-fuse concatenation(SF-Cat)and triple-scale sequence feature fusion(TSSF)module to merge multi-scale feature maps comprehensively.Depthwise convolution(DWConv)and GhostNet lighten the network,while the cross stage partial bottleneck with 3 convolutions ghost-normalization attention module(C3-GN)reduces missed detections by suppressing irrelevant background information.Finally,soft non-maximum suppression(Soft-NMS)is used in the post-processing stage to improve the problem of misdetection of dense disease sites.The results show that the MSL-Net improves mean average precision at intersection over union of 0.5(mAP@0.5)by 2.0%over the baseline you only look once version 5s(YOLOv5s)and reduces parameters by 44%,reducing computation by 27%,outperforming other state-of-the-art(SOTA)models overall.This method also shows excellent performance compared to the latest research. 展开更多
关键词 enhance focus disease features background i multi scale feature fusion apple leaf disease spots residual bottleneck block res bottleneck multiplexed aggregated feature extraction network lightweight network apple leaf disease detection
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基于Multi‑Agent模型的电力物联网无线覆盖测试方法研究
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作者 朱志康 龚庆武 +3 位作者 刘剑 马世乾 何潇 闫立东 《武汉大学学报(工学版)》 北大核心 2025年第7期1162-1171,共10页
为解决传统测试系统自主性较差、测试覆盖率和网络通讯资源利用率较低的问题,提出基于Multi-Agent模型的电力物联网无线覆盖测试方法,并给出测试方法的原理、无线连接方式、系统结构以及测试过程。通过NetLogo 3D软件建立基于Multi-Agen... 为解决传统测试系统自主性较差、测试覆盖率和网络通讯资源利用率较低的问题,提出基于Multi-Agent模型的电力物联网无线覆盖测试方法,并给出测试方法的原理、无线连接方式、系统结构以及测试过程。通过NetLogo 3D软件建立基于Multi-Agent模型的电力物联网无线覆盖测试仿真模型。仿真结果表明:与传统测试方法相比,所提方法具有更低的无线电发射功耗和带宽占用,测试过程无需人工操作测试装置,测试效率、自主性以及测试覆盖率都得到了较大提高。 展开更多
关键词 电力物联网 无线覆盖测试 multi-AGENT 分布式 NetLogo 3D
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Multi-objective optimization of grinding process parameters for improving gear machining precision 被引量:1
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作者 YOU Tong-fei HAN Jiang +4 位作者 TIAN Xiao-qing TANG Jian-ping LU Yi-guo LI Guang-hui XIA Lian 《Journal of Central South University》 2025年第2期538-551,共14页
The gears of new energy vehicles are required to withstand higher rotational speeds and greater loads,which puts forward higher precision essentials for gear manufacturing.However,machining process parameters can caus... The gears of new energy vehicles are required to withstand higher rotational speeds and greater loads,which puts forward higher precision essentials for gear manufacturing.However,machining process parameters can cause changes in cutting force/heat,resulting in affecting gear machining precision.Therefore,this paper studies the effect of different process parameters on gear machining precision.A multi-objective optimization model is established for the relationship between process parameters and tooth surface deviations,tooth profile deviations,and tooth lead deviations through the cutting speed,feed rate,and cutting depth of the worm wheel gear grinding machine.The response surface method(RSM)is used for experimental design,and the corresponding experimental results and optimal process parameters are obtained.Subsequently,gray relational analysis-principal component analysis(GRA-PCA),particle swarm optimization(PSO),and genetic algorithm-particle swarm optimization(GA-PSO)methods are used to analyze the experimental results and obtain different optimal process parameters.The results show that optimal process parameters obtained by the GRA-PCA,PSO,and GA-PSO methods improve the gear machining precision.Moreover,the gear machining precision obtained by GA-PSO is superior to other methods. 展开更多
关键词 worm wheel gear grinding machine gear machining precision machining process parameters multi objective optimization
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Multi-scale feature fusion optical remote sensing target detection method 被引量:1
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作者 BAI Liang DING Xuewen +1 位作者 LIU Ying CHANG Limei 《Optoelectronics Letters》 2025年第4期226-233,共8页
An improved model based on you only look once version 8(YOLOv8)is proposed to solve the problem of low detection accuracy due to the diversity of object sizes in optical remote sensing images.Firstly,the feature pyram... An improved model based on you only look once version 8(YOLOv8)is proposed to solve the problem of low detection accuracy due to the diversity of object sizes in optical remote sensing images.Firstly,the feature pyramid network(FPN)structure of the original YOLOv8 mode is replaced by the generalized-FPN(GFPN)structure in GiraffeDet to realize the"cross-layer"and"cross-scale"adaptive feature fusion,to enrich the semantic information and spatial information on the feature map to improve the target detection ability of the model.Secondly,a pyramid-pool module of multi atrous spatial pyramid pooling(MASPP)is designed by using the idea of atrous convolution and feature pyramid structure to extract multi-scale features,so as to improve the processing ability of the model for multi-scale objects.The experimental results show that the detection accuracy of the improved YOLOv8 model on DIOR dataset is 92%and mean average precision(mAP)is 87.9%,respectively 3.5%and 1.7%higher than those of the original model.It is proved the detection and classification ability of the proposed model on multi-dimensional optical remote sensing target has been improved. 展开更多
关键词 multi scale feature fusion optical remote sensing feature map improve target detection ability optical remote sensing imagesfirstlythe target detection feature fusionto enrich semantic information spatial information
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Multi-shooting非线性MPC无人驾驶汽车轨迹跟踪控制 被引量:1
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作者 朱仲文 蒋智涛 +2 位作者 王维志 江维海 李书华 《控制理论与应用》 北大核心 2025年第8期1477-1485,共9页
针对复杂路径下无人驾驶汽车轨迹跟踪精度不足和稳定性差的问题,本文研究了非线性MPC轨迹跟踪控制策略.首先基于brush轮胎模型建立了考虑轮胎滑移的车辆动力学模型.然后利用Multi-shooting算法将状态方程转化为函数连续性约束,独立计算... 针对复杂路径下无人驾驶汽车轨迹跟踪精度不足和稳定性差的问题,本文研究了非线性MPC轨迹跟踪控制策略.首先基于brush轮胎模型建立了考虑轮胎滑移的车辆动力学模型.然后利用Multi-shooting算法将状态方程转化为函数连续性约束,独立计算每个预测子区间的状态微分方程组,采用序列二次规划方法对非线性最优控制问题进行求解,得到最优控制输入.最后通过CarSim和MATLAB进行联合仿真,分别在36 km/h,54km/h和72 km/h3种车速下跟踪双移线轨迹,与传统的线性MPC控制器对比,3种车速下本文的控制策略横向跟踪累积误差降低了41.6%,46.6%和36.5%,控制效果得到提高,对不同车速有较好的鲁棒性.与基于Single-shooting的非线性MPC控制器对比,计算效率提高了61.9%,60%和52.8%,算法实时性得到了提高. 展开更多
关键词 无人驾驶汽车 轨迹跟踪 模型预测控制 multi-shooting算法
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便携式拉曼光谱仪结合CGAN-Multi-CNN模型的矿物精确识别方法研究
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作者 向艳芳 石红 +1 位作者 张家臣 蔡耀仪 《分析测试学报》 北大核心 2025年第6期1075-1085,共11页
野外环境下天然未知矿物的快速识别受限于不同光谱设备分辨率差异、样本量不足导致的模型泛化能力弱以及高维复杂光谱特征的提取能力有限这三个难题。为了解决上述难题,该文设计并实现了一种多尺度卷积神经网络结合光谱样本生成的拉曼... 野外环境下天然未知矿物的快速识别受限于不同光谱设备分辨率差异、样本量不足导致的模型泛化能力弱以及高维复杂光谱特征的提取能力有限这三个难题。为了解决上述难题,该文设计并实现了一种多尺度卷积神经网络结合光谱样本生成的拉曼光谱分类模型,并联立便携式拉曼光谱仪实现了野外未知矿物的快速识别。首先,三次样条曲线拟合算法被用于实现不同设备所采集光谱的维数匹配,从而消除不同光谱设备之间采样分辨率的差异。其次,全球矿物光谱库包含1648类矿物的5668个光谱样本被送入生成对抗网络进行训练并产生15000个扩增样本,从而缓解了数据稀缺性对模型分类性能的制约。此外,一种新的多尺度深度卷积网络被用于同步提取拉曼光谱的宽峰与窄峰特征,从而增强复杂光谱的表征能力。实验中将所提出的模型与k-近邻(k-NN)、支持向量机(SVM)和随机森林(RF)等几类经典机器学习模型对未知矿物的识别性能进行对比。结果表明,所提出的多尺度卷积神经网络结合光谱样本生成的分类模型对未知矿物拉曼光谱的判别准确率远超其他传统机器学习模型,其top-1和top-3的准确率值分别为93.26%和98.94%。使用所提出的模型结合便携式拉曼光谱系统对50类未知天然矿石样本进行了识别,其准确率达到100%,单个样本的识别时间仅为1~2 min,体现了该方法快速、精确和无需取样制样的优势。 展开更多
关键词 拉曼光谱 矿物识别 重采样方法 多尺度卷积网络 条件生成对抗网络(CGAN)样本生成
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Equality and Inclusiveness&Harmonious Coexistence:Multi-dimensional Narratives of Civilisations from Writers'Perspective
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《International Understanding》 2025年第2期24-25,共2页
On the evening of May 3Oth,the parallel forum"Equality and Inclusiveness&Harmonious Coexistence:Multi-dimensional Narratives of Civilisations from Writers'Perspective",as part of the 4th Dialogue on ... On the evening of May 3Oth,the parallel forum"Equality and Inclusiveness&Harmonious Coexistence:Multi-dimensional Narratives of Civilisations from Writers'Perspective",as part of the 4th Dialogue on Exchanges and Mutual Learning among Civilisations,was held in Dunhuang.The forum was organised by the China Writers Association and co-organised by China National Publications Import&Export(Group)Corporation. 展开更多
关键词 INCLUSIVENESS dialogue EXCHANGES multi dimensional narratives civilisations writers perspective exchanges mutual learning EQUALITY
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Characterization of Charged Lunar Dust in Multi-Source Irradiation Environments and Its Ground Simulation
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作者 Yun Chen Lifang Li +4 位作者 Jihong Yan Chengyue Sun Yunlong Li Dandan Ju Chunlong Wang 《Journal of Earth Science》 2025年第4期1867-1876,共10页
0 INTRODUCTION The lunar surface lacks an atmosphere and is continuously subjected to a combination of space weathering factors such as cosmic rays,solar wind,and micrometeorite impacts,forming a several-meter-thick l... 0 INTRODUCTION The lunar surface lacks an atmosphere and is continuously subjected to a combination of space weathering factors such as cosmic rays,solar wind,and micrometeorite impacts,forming a several-meter-thick lunar regolith(Sorokin et al.,2020). 展开更多
关键词 DUST multi source IRRADIATION micrometeorite impactsforming LUNAR lunar regolith sorokin cosmic rayssolar windand space weathering factors
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Multi-phase evolution of MOFs involving crystal,liquid and glass:New dynamic chemistry
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作者 Jia-Xin Wu Zheng Yin Ming-Hua Zeng 《Chinese Journal of Structural Chemistry》 2025年第10期11-13,共3页
The remarkable power of chemistry over description and trans-formation of matters has been significantly enhanced through the development of dynamic chemistry and condensed matter chemistry[1].This progress has furthe... The remarkable power of chemistry over description and trans-formation of matters has been significantly enhanced through the development of dynamic chemistry and condensed matter chemistry[1].This progress has further elevated chemistry to a creative science and a thriving industry.The development of dynamic chemistry,span-ning from supramolecular chemistry to constitutional dynamic chem-istry,has witnessed significant advancements towards adaptive chemistry,which is characterized primarily by its self-adaption to external stimuli.This is particularly achieved in two-or three-dimensional dynamic frameworks.Meanwhile,the multi-phase evolution resulting from the emerging of solid-to-liquid transition plat-form is assuming an increasingly crucial role in condensed matter chemistry[2]. 展开更多
关键词 CRYSTAL dynamic chemistryspan ning LIQUID dynamic chemistry condensed matter chemistry multi phase evolution GLASS adaptive chemistrywhich
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Modeling of the Multi-Target Locating and Tracking in the Field Artillery System 被引量:1
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作者 杨国胜 窦丽华 +1 位作者 陈杰 侯朝桢 《Journal of Beijing Institute of Technology》 EI CAS 2002年第1期14-18,共5页
A method for the multi target locating and tracking with the multi sensor in a field artillery system is studied. A general modeling structure of the system is established. Based on concepts of cluster and closed ba... A method for the multi target locating and tracking with the multi sensor in a field artillery system is studied. A general modeling structure of the system is established. Based on concepts of cluster and closed ball, an algorithm is put forward for multi sensor multi target data fusion and an optimal solution for state estimation is presented. The simulation results prove the algorithm works well for the multi stationary target locating and the multi moving target tracking under the condition of the sparse target environment. Therefore, this method can be directly applied to the field artillery C 3I system. 展开更多
关键词 field artillery system data fusion closed ball cluster single sensor multi target multi sensor multi target
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Dynamic Modeling of a Novel Multi-Loop Multi-Body Mechanism of Face-Shovel Excavator
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作者 Jisong Ding Huafeng Ding Wenjian Yang 《Chinese Journal of Mechanical Engineering》 2025年第1期323-339,共17页
Currently,research in multi-body dynamics predominantly focuses on symmetric parallel mechanisms with multiple branches.However,for the working mechanism(WM)of a face-shovel hydraulic excavator,an asymmetric mechanism... Currently,research in multi-body dynamics predominantly focuses on symmetric parallel mechanisms with multiple branches.However,for the working mechanism(WM)of a face-shovel hydraulic excavator,an asymmetric mechanism with multiple closed loops,there is a significant lack of research on dynamic models that account for the mass and inertia of all its moving components.The main focus of this study is to research a dynamic model of multi-closed-loop multi-body planar mechanism considering all moving components.This paper introduces a novel WM for a face-shovel excavator,featuring 4 loops and 12 links.By loop decomposition,the kinematic equations of the 11 primary moving components of the WM,including position,velocity,angular velocity,acceleration,and angular acceleration,are accurately formulated.For comparative analysis,a simplified dynamic model of WM was established,considering only the boom,stick,and bucket.The complete dynamic models based on the virtual work principle were also established.The correctness of both the simplified and complete dynamic models was verified through numerical simulations in Adams software.A comparison of simplified and complete dynamic simulation results shows that the new complete dynamic model has the advantage of accuracy.This research proposes a kinematic and dynamic modeling method with reference significance for the kinematic and dynamic analysis of planar complex multi-loop mechanisms,laying a foundation for performance analysis and the design of excavator WMs. 展开更多
关键词 Hydraulic face-shovel excavator DYNAMIC Kinematic Planer multi rigid body mechanism Virtual work
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Pavement Crack Extraction Based on Multi⁃scale Convolutional Neural Network
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作者 ZHAN Biheng SONG Xiangyu +2 位作者 CHENG Jianrui QIAO Pan WANG Tengfei 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第6期749-766,共18页
Cracks represent a significant hazard to pavement integrity,making their efficient and automated extraction essential for effective road health monitoring and maintenance.In response to this challenge,we propose a cra... Cracks represent a significant hazard to pavement integrity,making their efficient and automated extraction essential for effective road health monitoring and maintenance.In response to this challenge,we propose a crack automatic extraction network model that integrates multi⁃scale image features,thereby enhancing the model’s capability to capture crack characteristics and adaptation to complex scenarios.This model is based on the ResUNet architecture,makes modification to the convolutional layer of the model,proposes to construct multiple branches utilizing different convolution kernel sizes,and adds a atrous spatial pyramid pooling module within the intermediate layers.In this paper,comparative experiments on the performance of the basic model,ablation experiments,comparative experiments before and after data augmentation,and generalization verification experiments are conducted.Comparative experimental results indicate that the improved model exhibits superior detail processing capability at crack edges.The overall performance of the model,as measured by the F1⁃score,reaches 71.03%,reflecting a 2.1%improvement over the conventional ResUNet. 展开更多
关键词 road engineering neural networks multi⁃scale convolution pavement cracks
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