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基于改进PointPillars的自动驾驶障碍物点云检测算法
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作者 沈跃 沈卓凡 +2 位作者 刘慧 周昊 曾潇 《江苏大学学报(自然科学版)》 北大核心 2026年第2期125-133,共9页
针对自动驾驶场景下,近处干扰点云误检率高、远处稀疏点云漏检率高的问题,提出了一种基于改进PointPillars的自动驾驶障碍物点云检测算法.首先,通过聚合模块和共享多层感知机(shared multi-layer perceptron,MLP)对柱体内点云进行特征编... 针对自动驾驶场景下,近处干扰点云误检率高、远处稀疏点云漏检率高的问题,提出了一种基于改进PointPillars的自动驾驶障碍物点云检测算法.首先,通过聚合模块和共享多层感知机(shared multi-layer perceptron,MLP)对柱体内点云进行特征编码,采用最大池化与平均池化叠加的方法将点云的显著特征与细节特征映射为柱体特征;其次,针对算法对伪图特征关注与利用不充分的问题,引入坐标注意力(coordinate attention,CA)机制和残差连接的伪图特征提取模块(attention and residual second block,ARSB),将深层与浅层特征图进行融合,优化算法梯度,增强算法对有效目标的关注度.试验结果表明:改进算法对全局点云检测精度较高,平均精度优于PointPillars、稀疏到稠密3D目标检测器(STD)等点云目标检测算法,在汽车类别上的检测精度优势明显,检测速度较快,符合实时性要求. 展开更多
关键词 障碍物点云 深度学习 点云目标检测 点云柱体编码 伪图特征提取模块
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Potential mechanisms of non-coding RNA regulation in Alzheimer's disease 被引量:2
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作者 Yue Sun Xinping Pang +5 位作者 Xudong Huang Dinglu Liu Jingyue Huang Pengtao Zheng Yanyu Wei Chaoyang Pang 《Neural Regeneration Research》 2026年第1期265-280,共16页
Alzheimer's disease,a progressively degenerative neurological disorder,is the most common cause of dementia in the elderly.While its precise etiology remains unclear,researchers have identified diverse pathologica... Alzheimer's disease,a progressively degenerative neurological disorder,is the most common cause of dementia in the elderly.While its precise etiology remains unclear,researchers have identified diverse pathological characteristics and molecular pathways associated with its progression.Advances in scientific research have increasingly highlighted the crucial role of non-coding RNAs in the progression of Alzheimer's disease.These non-coding RNAs regulate several biological processes critical to the advancement of the disease,offering promising potential as therapeutic targets and diagnostic biomarkers.Therefore,this review aims to investigate the underlying mechanisms of Alzheimer's disease onset,with a particular focus on microRNAs,long non-coding RNAs,and circular RNAs associated with the disease.The review elucidates the potential pathogenic processes of Alzheimer's disease and provides a detailed description of the synthesis mechanisms of the three aforementioned non-coding RNAs.It comprehensively summarizes the various non-coding RNAs that have been identified to play key regulatory roles in Alzheimer's disease,as well as how these noncoding RNAs influence the disease's progression by regulating gene expression and protein functions.For example,miR-9 targets the UBE4B gene,promoting autophagy-mediated degradation of Tau protein,thereby reducing Tau accumulation and delaying Alzheimer's disease progression.Conversely,the long non-coding RNA BACE1-AS stabilizes BACE1 mRNA,promoting the generation of amyloid-βand accelerating Alzheimer's disease development.Additionally,circular RNAs play significant roles in regulating neuroinflammatory responses.By integrating insights from these regulatory mechanisms,there is potential to discover new therapeutic targets and potential biomarkers for early detection and management of Alzheimer's disease.This review aims to enhance the understanding of the relationship between Alzheimer's disease and non-coding RNAs,potentially paving the way for early detection and novel treatment strategies. 展开更多
关键词 Alzheimer's disease biomarkers circular RNA long non-coding RNA MICRORNA ncRNA regulation NEURODEGENERATION non-coding RNA PATHOGENESIS therapeutic targets
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基于WSS-Pointnet的变电站点云弱监督语义分割方法
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作者 裴少通 孙海超 +2 位作者 胡晨龙 王玮琦 兰博 《电工技术学报》 北大核心 2026年第1期234-245,共12页
现有的变电站点云语义分割算法均采用完全监督学习,需要大量人工标注点云数据,导致分割任务耗时长且成本高昂。为解决这一问题,该文提出一种基于PointNet改进的弱监督语义分割PointNet(WSS-PointNet)算法。首先,通过构建多层降采样结构... 现有的变电站点云语义分割算法均采用完全监督学习,需要大量人工标注点云数据,导致分割任务耗时长且成本高昂。为解决这一问题,该文提出一种基于PointNet改进的弱监督语义分割PointNet(WSS-PointNet)算法。首先,通过构建多层降采样结构,结合采样层与分组层对输入点云数据进行多尺度特征提取,从而捕捉点云在不同尺度上的几何和拓扑信息。在此基础上,引入PointNet结构以进一步提取区域特征,优化局部特征整合与全局特征表示;针对粗粒度语义特征的优化,提出膨胀式语义信息嵌入与浸染式语义信息嵌入两种模块,分别采用“由内而外”和“由外而内”的信息传递策略对点云语义信息进行细致处理,两种嵌入机制均基于图卷积神经网络,通过捕捉局部连接模式与信息共享实现语义特征的高效传播。其次,构建变电站点云数据集,并对WSS-PointNet算法进行消融实验,同时与主流的完全监督学习算法和弱监督学习算法进行对比。经实验验证,WSS-PointNet相比于改进前将变电站点云分割的总体精度(OA)提高了10.3个百分点,平均交并比(mIoU)提高了10.1个百分点,平均准确率(mAcc)提高了10.5个百分点,同时在标注所需时间方面缩短了90%,接近完全监督算法中最好的分割效果。该模型可显著降低处理变电站点云数据的时间与成本,同时保持点云分割的高精度。 展开更多
关键词 点云语义分割 弱监督方法 膨胀式语义信息嵌入 浸染式语义信息嵌入 变电站
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PT-MFR:一种基于Point Transformer的CAD模型加工特征识别方法
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作者 何皓辰 方正 +2 位作者 卢政达 肖俊 王颖 《中国科学院大学学报(中英文)》 北大核心 2026年第1期115-124,共10页
加工特征识别在计算机辅助设计(CAD)和制造(CAM)中至关重要,是连接CAD和CAM系统的重要环节。研究者们提出了基于规则和基于学习的2类加工特征识别方法,其中基于学习的方法表现更出色且备受关注。然而,现有识别方法面临着几何信息利用不... 加工特征识别在计算机辅助设计(CAD)和制造(CAM)中至关重要,是连接CAD和CAM系统的重要环节。研究者们提出了基于规则和基于学习的2类加工特征识别方法,其中基于学习的方法表现更出色且备受关注。然而,现有识别方法面临着几何信息利用不足、加工特征定位不精准、实例分割过程复杂等挑战。针对这些问题,提出PT-MFR,一种基于Point Transformer的CAD模型加工特征识别方法,它执行语义分割和实例分割2个任务,分别预测模型每个面的加工特征语义类别并计算面相似度以分割加工特征实例,综合2个任务得到加工特征识别结果。实验结果表明,提出的方法性能优于现有的其他方法。 展开更多
关键词 加工特征识别 点云 神经网络 point Transformer
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An enhanced segmentation method for 3D point cloud of tunnel support system using PointNet++t and coverage-voted strategy algorithms 被引量:1
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作者 Wenju Liu Fuqiang Gao +4 位作者 Shuangyong Dong Xiaoqing Wang Shuwen Cao Wanjie Wang Xiaomin Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1653-1660,共8页
3D laser scanning technology is widely used in underground openings for high-precision,rapid,and nondestructive structural evaluations.Segmenting large 3D point cloud datasets,particularly in coal mine roadways with m... 3D laser scanning technology is widely used in underground openings for high-precision,rapid,and nondestructive structural evaluations.Segmenting large 3D point cloud datasets,particularly in coal mine roadways with multi-scale targets,remains challenging.This paper proposes an enhanced segmentation method integrating improved PointNet++with a coverage-voted strategy.The coverage-voted strategy reduces data while preserving multi-scale target topology.The segmentation is achieved using an enhanced PointNet++algorithm with a normalization preprocessing head,resulting in a 94%accuracy for common supporting components.Ablation experiments show that the preprocessing head and coverage strategies increase segmentation accuracy by 20%and 2%,respectively,and improve Intersection over Union(IoU)for bearing plate segmentation by 58%and 20%.The accuracy of the current pretraining segmentation model may be affected by variations in surface support components,but it can be readily enhanced through re-optimization with additional labeled point cloud data.This proposed method,combined with a previously developed machine learning model that links rock bolt load and the deformation field of its bearing plate,provides a robust technique for simultaneously measuring the load of multiple rock bolts in a single laser scan. 展开更多
关键词 point cloud segmentation Improved pointNet++ Tunnel laser scanning Rock bolt automatic recognition
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基于改进PointNet++的服装点云分割与边界优化
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作者 徐诗琦 马玲 +2 位作者 林熹妍 潘怡婷 邹奉元 《现代纺织技术》 北大核心 2026年第2期90-98,共9页
人体与服装及服装不同部位之间的边界区域常包含复杂几何特征与变化,使得三维点云场景分割方法在进行服装提取时边界分割效果较差,进而影响整体精度。为了提高服装点云分割精度,提出一种融合边界识别的改进PointNet++模型,以提高边界区... 人体与服装及服装不同部位之间的边界区域常包含复杂几何特征与变化,使得三维点云场景分割方法在进行服装提取时边界分割效果较差,进而影响整体精度。为了提高服装点云分割精度,提出一种融合边界识别的改进PointNet++模型,以提高边界区域的分割性能。首先,对输入三维服装点云数据进行初步分割。接着,在初始部件分割结果的基础上,设计基于K邻近算法的边界识别模块并嵌入PointNet++模型,以对初步分割边界进行针对性训练。最后,利用优化后的局部区域提高三维服装的整体分割精度。结果表明:改进PointNet++模型方法在边界区域的总体精度与平均交并比分别为87.37%与86.68%,比基线方法分别提升了32.74%、34.25%。整体区域的总体精度与平均交并比分别为93.53%与92.84%,比基线方法分别提升了1.19%、0.89%。研究方法可显著提升三维服装边界分割精度,为三维服装提取提供技术参考。 展开更多
关键词 三维服装提取 三维点云 pointNet++ 点云分割 边界优化
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A DNA Damage-responsive Long Non-coding RNA lnc-DUSP6 Promotes Cisplatin-induced DNA Damage Repair and Chemoresistance
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作者 XU Shun WU Wei-Jia +8 位作者 YANG Hai-Qing HUANG Hai-Jiao YE Li-Wen ZHU Yue SHEN Jia-En ZHENG Xiao-Li HUANG Xiao-Lu SHEN Han-Lian LI Yu-Ting 《中国生物化学与分子生物学报》 北大核心 2026年第2期295-307,共13页
Genomic destabilization and defective DNA repair are the most prominent features of tumour cells and are exploited by various chemotherapy drugs for cancer therapy.Long non-coding RNA(lncR-NAs)have emerged as powerful... Genomic destabilization and defective DNA repair are the most prominent features of tumour cells and are exploited by various chemotherapy drugs for cancer therapy.Long non-coding RNA(lncR-NAs)have emerged as powerful regulators of gene expression and are thus involved in diverse biological processes.Recent studies have demonstrated that several lncRNAs play critical roles in DNA repair.Nonetheless,the relationship between DNA damage-responsive lncRNAs and chemoresistance remains poorly defined.In this study,we established four different DNA damage models triggered by cisplatin(DDP),H2O2,neocarzinostatin(NCS)or ultraviolet(UV)irradiation and identified a specific upregu-lated lncRNA(lnc-DUSP6)involved in the cisplatin-induced DNA damage response.Furthermore,loss-or gain-of-function experiments confirmed that lnc-DUSP6 enhanced DNA repair and cell survival under cisplatin treatment,thus promoting cisplatin resistance.Mechanistically,an RNA immunoprecipitation(RIP)assay revealed that lnc-DUSP6 directly interacts with DUSP6(Dual Specificity Phosphatase 6),which is closely associated with cisplatin sensitivity.Additionally,overexpression of DUSP6 significantly rescued the effects of lnc-DUSP6 silencing on DNA repair and cell survival under cisplatin treatment.O-verall,our results show the effect and underlying mechanism of lnc-DUSP6 in cisplatin resistance:lnc-DUSP6 promotes cisplatin-induced DNA damage repair and cisplatin resistance by stabilizing DUSP6,which is highly clinically important for enhancing the efficacy of cisplatin for cancers. 展开更多
关键词 long non-coding RNA(lncRNAs) CHEMORESISTANCE dual specificity protein phosphatase 6(DUSP6) lnc-DUSP6 DNA damage response(DDR)
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Helicobacter pylori-related non-coding RNAs in gastric cancer screening:Emerging evidence and translational challenges
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作者 Zuo-Po Lv Muhammad Haris Sultan Yi-Gang Wang 《World Journal of Gastrointestinal Oncology》 2026年第1期1-7,共7页
Gastric cancer(GC)has high morbidity and mortality worldwide.Due to the absence of noticeable symptoms,diagnosing GC at an early stage is very difficult,which consequently leads to advanced GC and poor prognosis.Effec... Gastric cancer(GC)has high morbidity and mortality worldwide.Due to the absence of noticeable symptoms,diagnosing GC at an early stage is very difficult,which consequently leads to advanced GC and poor prognosis.Effective biomarkers are essential for prolonging patients’survival.Helicobacter pylori(H.pylori)infection represents the most significant risk factor for GC,with nearly all cases linked to this infection.Many non-coding RNAs(ncRNAs)are dysregulated in H.pylori-infected GC,indicating that ncRNAs may serve as biomarkers of early-stage GC.In this editorial,we discuss the study by Chen et al.Although previous studies have identified roles for miR-136 in gastric cancer proliferation,apoptosis,and invasion,none have specifically explored its relationship with H.pylori-associated gastric carcinogenesis. 展开更多
关键词 Helicobacter pylori Gastric cancer non-coding RNA BIOMARKER Clinical challenges
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Novel insights into non-coding RNAs and their role in hydrocephalus
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作者 Zhiyue Cui Jian He +8 位作者 An Li Junqiang Wang Yijian Yang Kaiyue Wang Zhikun Liu Qian Ouyang Zhangjie Su Pingsheng Hu Gelei Xiao 《Neural Regeneration Research》 2026年第2期636-647,共12页
A large body of evidence has highlighted the role of non-coding RNAs in neurodevelopment and neuroinflammation.This evidence has led to increasing speculation that non-coding RNAs may be involved in the pathophysiolog... A large body of evidence has highlighted the role of non-coding RNAs in neurodevelopment and neuroinflammation.This evidence has led to increasing speculation that non-coding RNAs may be involved in the pathophysiological mechanisms underlying hydrocephalus,one of the most common neurological conditions worldwide.In this review,we first outline the basic concepts and incidence of hydrocephalus along with the limitations of existing treatments for this condition.Then,we outline the definition,classification,and biological role of non-coding RNAs.Subsequently,we analyze the roles of non-coding RNAs in the formation of hydrocephalus in detail.Specifically,we have focused on the potential significance of non-coding RNAs in the pathophysiology of hydrocephalus,including glymphatic pathways,neuroinflammatory processes,and neurological dysplasia,on the basis of the existing evidence.Lastly,we review the potential of non-coding RNAs as biomarkers of hydrocephalus and for the creation of innovative treatments. 展开更多
关键词 HYDROCEPHALUS NEURODEVELOPMENT NEUROINFLAMMATION non-coding RNA therapeutic target
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Decoding the complexity of coding and non-coding RNAs across maize anther development at the isoform level
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作者 Ge Yan Xuxu Ma +5 位作者 Wei Huang Chunyu Wang Yingjia Han Shufang Wang Han Liu Mei Zhang 《Journal of Genetics and Genomics》 2026年第1期163-176,共14页
Anther is a key male reproductive organ that is essential for the plant life cycle,from the sporophyte to the gametophyte generation.To explore the isoform-level transcriptional landscape of developing anthers in maiz... Anther is a key male reproductive organ that is essential for the plant life cycle,from the sporophyte to the gametophyte generation.To explore the isoform-level transcriptional landscape of developing anthers in maize(Zea mays L.),we analyzed Iso-Seq data from anthers collected at 10 developmental stages,together with strand-specific RNA-seq,CAGE-seq,and PAS-seq data.Of the 152,026 high-confidence full-length isoforms identified,68.8%have not been described;these include 22,365 isoforms that originate from previously unannotated loci and 82,167 novel isoforms that originate from annotated protein-coding genes.Using our newly developed strategy to detect dynamic expression patterns of isoforms,we identify 13,899 differentially variable regions(DVRs);surprisingly,1275 genes contain more than two DVRs,revealing highly efficient utilization of limited genic regions.We identify 7876 long non-coding RNAs(lncRNAs)from 4098 loci,most of which were preferentially expressed during cell differentiation and meiosis.We also detected 371 long-range interactions involving intergenic lncRNAs(lincRNAs);interestingly,243 were lincRNA-gene ones,and the interacting genes were highly expressed in anthers,suggesting that many potential lncRNA regulators of key genes are required for anther development.This study provides valuable resources and fundamental information for studying the essential transcripts of key genes during anther development. 展开更多
关键词 Anther development Long-read transcriptome sequencing ISOFORM Long non-coding RNA MAIZE
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The regulatory network composed of phytohormones,transcription factors and non-coding RNAs is involved in the flavonoids biosynthesis of fruits
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作者 Xiaoyuan Zheng Xuejiao Zhang Fankui Zeng 《Horticultural Plant Journal》 2026年第3期497-508,共12页
Flavonoids,abundant in the fruits,are pivotal to their growth,development,and storage.In addition,they have significant beneficial effects on human health.Consequently,research is increasingly concentrating on the reg... Flavonoids,abundant in the fruits,are pivotal to their growth,development,and storage.In addition,they have significant beneficial effects on human health.Consequently,research is increasingly concentrating on the regulatory mechanisms governing flavonoid biosynthesis in fruits.Phytohormones are involved in the regulation of flavonoid biosynthesis.The abscisic acid,ethylene,jasmonic acid,cytokinins,and brassinosteroids promote flavonoid biosynthesis,while auxin negatively regulates flavonoid biosynthesis.Subsequently,transcription factors from the MYB,bHLH,WRKY,NAC,and bZIP families are pivotal in regulating flavonoid biosynthesis.In addition,non-coding RNAs(microRNA and lncRNA)also participate in the regulation of flavonoids biosynthesis.MicroRNAs are generally believed to negatively regulate flavonoid metabolism in fruits,while lncRNAs have the opposite effect.Furthermore,the interactions between plant hormones,transcription factors,and non-coding RNAs in fruit flavonoid biosynthesis were analyzed.Ultimately,a foundational regulatory network for fruit flavonoid biosynthesis was hereby established. 展开更多
关键词 Flavonoids biosynthesis PHYTOHORMONE Transcription factor non-coding RNAs Regulation network Fruit
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A multi-tie points-based method for retrieving of the Arctic thin sea ice thickness from SMOS
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作者 LI Jiaxing ZHANG Shengkai +2 位作者 XIAO Feng GENG Tong LI Fei 《Advances in Polar Science》 2026年第1期43-55,共13页
The correlation between the Soil Moisture and Ocean Salinity(SMOS)L-band brightness temperature and thin sea ice thickness has been widely exploited using semi-empirical retrieval approaches based on a single-tie poin... The correlation between the Soil Moisture and Ocean Salinity(SMOS)L-band brightness temperature and thin sea ice thickness has been widely exploited using semi-empirical retrieval approaches based on a single-tie point(STP).However,due to pronounced spatial heterogeneity in seawater and sea ice properties across the Arctic,the use of an STP often leads to regionally biased.To address this limitation,this study proposes a multi-tie point(MTP)sea ice thickness retrieval method based on SMOS brightness temperature and sea ice concentration time series.Multiple seawater and sea ice tie-point values are identified through point-by-point time series analysis,quality control,and statistical hypothesis testing,allowing spatial variability in radiometric properties to be explicitly considered.The MTP-based retrieval is applied to Arctic freeze-up conditions.Validation against independent SMOS thin sea ice thickness products shows that the MTP approach yields significantly reduced bias and root mean square error compared with the conventional STP method,with statistically significant improvements confirmed by paired t-tests.While retrieval accuracy stabilizes beyond a certain number of tie points,the preprocessing cost associated with tie-point selection increases substantially.Considering both accuracy and efficiency,the MTP framework provides a practical and robust approach for large-scale Arctic thin sea ice thickness retrieval and enables improved characterization of regional freezing processes and maximum ice thickness. 展开更多
关键词 SMOS single-tie point ARCTIC multi-tie point thin sea ice thickness
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RP11-Derived Long Non-Coding RNAs in Hepatocellular Carcinoma:Hidden Treasures in Plain Sight
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作者 Se Ha Jang Hyung Seok Kim Jung Woo Eun 《Oncology Research》 2026年第1期89-104,共16页
Hepatocellular carcinoma(HCC)remains one of the most prevalent and lethal malignancies worldwide.Long non-coding RNAs(lncRNAs)have emerged as crucial regulators of gene expression and cancer progression,yet the functi... Hepatocellular carcinoma(HCC)remains one of the most prevalent and lethal malignancies worldwide.Long non-coding RNAs(lncRNAs)have emerged as crucial regulators of gene expression and cancer progression,yet the functional diversity of RP11-derived lncRNAs—originally mapped to bacterial artificial chromosome(BAC)clones from the Roswell Park Cancer Institute—has only recently begun to be appreciated.This mini-review aims to systematically synthesize current findings on RP11-derived lncRNAs in HCC,outlining their genomic origins,molecular mechanisms,and biological significance.We highlight their roles in metabolic reprogramming,microRNA network modulation,and tumor progression,as well as their diagnostic and prognostic value in tissue and serum-based analyses.Finally,we discuss therapeutic opportunities and propose future directions to translate RP11-derived lncRNAs into clinically actionable biomarkers and targets for precision liver cancer therapy. 展开更多
关键词 Hepatocellular carcinoma long non-coding RNA RP11-derived lncRNA BIOMARKER therapeutic target
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基于3DGP-PointRCNN的道路场景三维点云小目标检测
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作者 李洪涛 徐平平 +2 位作者 甘鹏明 孙士阳 张文兴 《现代电子技术》 北大核心 2026年第5期193-198,共6页
在自动驾驶场景中,检测远距离目标和小目标(如行人和骑行者)时,因其尺寸较小、形状复杂和点云稀疏,检测难度显著增加。为此,文中提出一种改进的三维目标检测方法(3DGP-PointRCNN)。该方法基于PointRCNN,首先,在特征提取阶段引入全局分... 在自动驾驶场景中,检测远距离目标和小目标(如行人和骑行者)时,因其尺寸较小、形状复杂和点云稀疏,检测难度显著增加。为此,文中提出一种改进的三维目标检测方法(3DGP-PointRCNN)。该方法基于PointRCNN,首先,在特征提取阶段引入全局分组坐标注意力(GGCA)模块,结合全局上下文信息和局部特征,通过加权融合的方式减少无关点的影响,提升网络对关键目标区域的关注能力;其次,基于PnP3D重新构建网络架构,通过K近邻搜索与全局双线性正则化方法,对点云局部邻域特征与全局特征进行深度融合,增强网络对目标形状和位置的精细建模能力;最后,基于KITTI数据集进行了实验对比。实验结果表明,改进后的网络模型相比基准网络,在困难级别下行人和骑行者的检测精度分别提升了1.83%和4.17%,汽车的检测精度提升了0.46%,特别是在小目标的检测精度上,所提方法的性能得到显著提升。 展开更多
关键词 三维目标检测 点云 pointRCNN 注意力机制 小目标检测 PnP3D
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基于Pointnet++的花生植株三维模型器官分割研究
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作者 孟兆凡 程曼 +1 位作者 袁洪波 赵欢 《中国农机化学报》 北大核心 2026年第1期118-127,共10页
基于点云进行三维重构并进行器官分割对植物学研究至关重要,为研究花生植株茎叶器官分割训练样本的数量和类型对分割结果的影响规律,基于Pointnet++构建花生植株三维模型茎叶分割网络模型,并对比分析训练集类型以及数量对分割效果的影... 基于点云进行三维重构并进行器官分割对植物学研究至关重要,为研究花生植株茎叶器官分割训练样本的数量和类型对分割结果的影响规律,基于Pointnet++构建花生植株三维模型茎叶分割网络模型,并对比分析训练集类型以及数量对分割效果的影响。当训练集为10株花生幼苗期数据时,模型分割效果最好,准确率、类平均准确率、类平均交并比、F1分数分别为94.5%、81.9%、76.9%、85.7%。其中,在花生荚果期训练集中加入20株开花期数据,类平均准确率、类平均交并比分别上升19.55%、20.75%。试验结果表明,Pointnet++可以有效分割花生植株茎叶器官,训练集的多样性和数据量的增加有利于模型学习花生植株不同生长阶段的形态特征,在训练集中加入相近生长阶段和生长特征的模型数据,并增加数据量对模型分割效果提高更明显。 展开更多
关键词 花生植株 三维建模 点云 器官分割 训练集
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Exceptional point-induced knot structure transformations in non-Abelian braids
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作者 Lin-Sheng Bao Jia-Yun Ning +5 位作者 Ao-Qian Shi Peng Peng Zhen-Nan Wang Chao Peng Shuang-Chun Wen Jian-Jun Liu 《Chinese Physics B》 2026年第1期212-217,共6页
The strong connection between braids and knots provides valuable insights into studying the topological state and phase classification of various physical systems.The phenomenon of non-Hermitian(NH)two-and three-band ... The strong connection between braids and knots provides valuable insights into studying the topological state and phase classification of various physical systems.The phenomenon of non-Hermitian(NH)two-and three-band braiding has received widespread attention.However,a systematic exploration and visualization of non-Abelian braiding and the associated knot transformations in four-band systems remains unexplored.Here,we propose a theoretical model of NH four-band braiding,provide its phase diagram,and establish its trivial,Abelian,and non-Abelian braiding rules.Additionally,we report on special knots,such as the Hopf and Solomon links in braided knots,and reveal that their transformations are accompanied by and mediated through exceptional points.Our work provides a detailed case for studying NH multiband braiding and knot structures in four-band systems,which could offer insights for topological photonics and analog information processing applications. 展开更多
关键词 exceptional point knot structures phase transitions non-Abelian braids
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Rock Discontinuity Extraction from 3D Point Clouds:Application to Identifying Geological Structures in the Miocene-Pliocene Deposits,Japan
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作者 Masahiro Ohkawa Kota Osawa +1 位作者 Ryo Okino Shigeaki Matsuo 《Journal of Environmental & Earth Sciences》 2026年第1期29-46,共18页
Evaluating rock mass quality using three-dimensional(3D)point clouds is crucial for discontinuity extraction and is widely applied in various industrial sectors.However,the utilization of this method in geological sur... Evaluating rock mass quality using three-dimensional(3D)point clouds is crucial for discontinuity extraction and is widely applied in various industrial sectors.However,the utilization of this method in geological surveys remains limited.Notable limitations of current research include the scarcity of validation using simple geometric shapes for discontinuity extraction methods,and the lack of studies that target both planar and linear discontinuity.To address these gaps,this study proposes a workflow for identifying discontinuity planes and traces in rock outcrops from photogrammetric 3D modeling,employing the Compass and Facets plugins in the open-source CloudCompare software.Prior to field application,the efficacy of the extraction methods was first evaluated using experimental datasets of a cube and an isosceles triangular prism generated under laboratory-controlled conditions.This validation demonstrated exceptional accuracy,with the dip and dip direction(DDD)of extracted structures consistently within±2°of the actual values.Following this rigorous laboratory validation,this methodology was applied to a more complex natural rock outcrop(Miocene–Pliocene deposits in Japan),demonstrating its applicability in realistic geological settings for identifying structures.The results showed that the dip and dip direction trends of the extracted bedding planes and faults were consistent with field measurements,achieving a time reduction of approximately 40%compared to traditional methods.In conclusion,through strictly controlled initial verification and subsequent successful application to a complex natural setting,this study confirmed that the proposed workflow can effectively and efficiently extract discontinuous geological structures from point clouds. 展开更多
关键词 Digital Outcrop Model Rock Discontinuities Geological Information point Cloud
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Multiple PointMedSAM Prompting for Enhanced Medical Image Segmentation
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作者 Wasfieh Nazzal Ezequiel López-Rubio +1 位作者 Miguel A.Molina-Cabello Karl Thurnhofer-Hemsi 《Computers, Materials & Continua》 2026年第5期2100-2115,共16页
Automatic and accurate medical image segmentation remains a fundamental task in computer-aided diagnosis and treatment planning.Recent advances in foundation models,such as the medical-focused Segment AnythingModel(Me... Automatic and accurate medical image segmentation remains a fundamental task in computer-aided diagnosis and treatment planning.Recent advances in foundation models,such as the medical-focused Segment AnythingModel(MedSAM),have demonstrated strong performance but face challenges inmanymedical applications due to anatomical complexity and a limited domain-specific prompt.Thiswork introduces amethodology that enhances segmentation robustness and precision by automatically generating multiple informative point prompts,rather than relying on single inputs.The proposed approach randomly samples sets of spatially distributed point prompts based on image features,enabling MedSAM to better capture fine-grained anatomical structures and boundaries.During inference,probability maps are aggregated to reduce local misclassifications without additional model training.Extensive experiments on various computed tomography(CT)and magnetic resonance imaging(MRI)datasets demonstrate improvements in Dice Similarity Coefficient(DSC)and Normalized Surface Dice(NSD)metrics compared to baseline SAM and Scribble Prompt models.A semi-automatic point sampling version based on the ground truth segmentations yielded enhanced results,achieving up to 92.1%DSC and 86.6%NSD,with significant gains in delineating complex organs such as the pancreas,colon,kidney,and brain tumours.The main novelty of our method consists of effectively combining the results of multiple point prompts into the medical segmentation pipeline so that single-point prompt methods are outperformed.Overall,the proposed model offers a straightforward yet effective approach to improve medical image segmentation performance while maintaining computational efficiency. 展开更多
关键词 Medical image segmentation deep learning test-time augmentation point prompt
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Ultrastructure and key identification points of fossilized Os Draconis in traditional Chinese medicine
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作者 Dong-Han Bai Zi Xing +5 位作者 Zi-Hao Zhang Zhi-Jie Zhang Da-Jun Lu Nan-Xi Huang Qiao-Chu Wang Lu Luo 《Traditional Medicine Research》 2026年第1期39-46,共8页
Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewa... Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewable,and clinical demand is increasingly difficult to meet,leading to a proliferation of counterfeit products.During prolonged geological burial,static pressure from the surrounding strata severely compromises the microstructural integrity of osteons in Os Draconis,but Os Draconis still largely retains the structural features of mammalian bone.Methods:Using verified authentic Os Draconis samples over 10,000 years old as a baseline,this study summarizes the ultrastructural characteristics of genuine Os Draconis.Employing electron probe microanalysis and optical polarized light microscopy,we examined 28 batches of authentic Os Draconis and 31 batches of counterfeits to identify their ultrastructural differences.Key points for ultrastructural identification of Os Draconis were compiled,and a new identification approach was proposed based on these differences.Results:Authentic Os Draconis exhibited distinct ultrastructural markers:irregularly shaped osteons with traversing fissures,deformed/displaced Haversian canals,and secondary mineral infill(predominantly calcium carbonate).Counterfeits showed regular osteon arrangements,absent traversal fissures,and homogeneous hydroxyapatite composition.Lab-simulated samples lacked structural degradation features.EPMA confirmed calcium carbonate infill in fossilized Haversian canals,while elemental profiles differentiated lacunae types(void vs.mineral-packed).Conclusion:The study established ultrastructural criteria for authentic Os Draconis identification:osteon deformation,geological fissures penetrating bone units,and heterogenous mineral deposition.These features,unattainable in counterfeits or modern processed bones,provide a cost-effective,accurate identification method.This approach bridges gaps in TCM material standardization and supports quality control for clinical applications. 展开更多
关键词 Os Draconis ULTRASTRUCTURE identification points electron probe polarized light microscope
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Federated Dynamic Aggregation Selection Strategy-Based Multi-Receptive Field Fusion Classification Framework for Point Cloud Classification
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作者 Yuchao Hou Biaobiao Bai +3 位作者 Shuai Zhao Yue Wang Jie Wang Zijian Li 《Computers, Materials & Continua》 2026年第2期1889-1918,共30页
Recently,large-scale deep learning models have been increasingly adopted for point cloud classification.However,thesemethods typically require collecting extensive datasets frommultiple clients,which may lead to priva... Recently,large-scale deep learning models have been increasingly adopted for point cloud classification.However,thesemethods typically require collecting extensive datasets frommultiple clients,which may lead to privacy leaks.Federated learning provides an effective solution to data leakage by eliminating the need for data transmission,relying instead on the exchange of model parameters.However,the uneven distribution of client data can still affect the model’s ability to generalize effectively.To address these challenges,we propose a new framework for point cloud classification called Federated Dynamic Aggregation Selection Strategy-based Multi-Receptive Field Fusion Classification Framework(FDASS-MRFCF).Specifically,we tackle these challenges with two key innovations:(1)During the client local training phase,we propose a Multi-Receptive Field Fusion Classification Model(MRFCM),which captures local and global structures in point cloud data through dynamic convolution and multi-scale feature fusion,enhancing the robustness of point cloud classification.(2)In the server aggregation phase,we introduce a Federated Dynamic Aggregation Selection Strategy(FDASS),which employs a hybrid strategy to average client model parameters,skip aggregation,or reallocate local models to different clients,thereby balancing global consistency and local diversity.We evaluate our framework using the ModelNet40 and ShapeNetPart benchmarks,demonstrating its effectiveness.The proposed method is expected to significantly advance the field of point cloud classification in a secure environment. 展开更多
关键词 point cloud classification federated learning multi-receptive field fusion dynamic aggregation
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