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Weighted Multi-sensor Data Level Fusion Method of Vibration Signal Based on Correlation Function 被引量:7
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作者 BIN Guangfu JIANG Zhinong +1 位作者 LI Xuejun DHILLON B S 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第5期899-904,共6页
As the differences of sensor's precision and some random factors are difficult to control,the actual measurement signals are far from the target signals that affect the reliability and precision of rotating machinery... As the differences of sensor's precision and some random factors are difficult to control,the actual measurement signals are far from the target signals that affect the reliability and precision of rotating machinery fault diagnosis.The traditional signal processing methods,such as classical inference and weighted averaging algorithm usually lack dynamic adaptability that is easy for trends to cause the faults to be misjudged or left out.To enhance the measuring veracity and precision of vibration signal in rotary machine multi-sensor vibration signal fault diagnosis,a novel data level fusion approach is presented on the basis of correlation function analysis to fast determine the weighted value of multi-sensor vibration signals.The approach doesn't require knowing the prior information about sensors,and the weighted value of sensors can be confirmed depending on the correlation measure of real-time data tested in the data level fusion process.It gives greater weighted value to the greater correlation measure of sensor signals,and vice versa.The approach can effectively suppress large errors and even can still fuse data in the case of sensor failures because it takes full advantage of sensor's own-information to determine the weighted value.Moreover,it has good performance of anti-jamming due to the correlation measures between noise and effective signals are usually small.Through the simulation of typical signal collected from multi-sensors,the comparative analysis of dynamic adaptability and fault tolerance between the proposed approach and traditional weighted averaging approach is taken.Finally,the rotor dynamics and integrated fault simulator is taken as an example to verify the feasibility and advantages of the proposed approach,it is shown that the multi-sensor data level fusion based on correlation function weighted approach is better than the traditional weighted average approach with respect to fusion precision and dynamic adaptability.Meantime,the approach is adaptable and easy to use,can be applied to other areas of vibration measurement. 展开更多
关键词 vibration signal MULTI-SENSOR data level fusion correlation function weighted value
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Fusion of Activation Functions: An Alternative to Improving Prediction Accuracy in Artificial Neural Networks
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作者 Justice Awosonviri Akodia Clement K. Dzidonu +1 位作者 David King Boison Philip Kisembe 《World Journal of Engineering and Technology》 2024年第4期836-850,共15页
The purpose of this study was to address the challenges in predicting and classifying accuracy in modeling Container Dwell Time (CDT) using Artificial Neural Networks (ANN). This objective was driven by the suboptimal... The purpose of this study was to address the challenges in predicting and classifying accuracy in modeling Container Dwell Time (CDT) using Artificial Neural Networks (ANN). This objective was driven by the suboptimal outcomes reported in previous studies and sought to apply an innovative approach to improve these results. To achieve this, the study applied the Fusion of Activation Functions (FAFs) to a substantial dataset. This dataset included 307,594 container records from the Port of Tema from 2014 to 2022, encompassing both import and transit containers. The RandomizedSearchCV algorithm from Python’s Scikit-learn library was utilized in the methodological approach to yield the optimal activation function for prediction accuracy. The results indicated that “ajaLT”, a fusion of the Logistic and Hyperbolic Tangent Activation Functions, provided the best prediction accuracy, reaching a high of 82%. Despite these encouraging findings, it’s crucial to recognize the study’s limitations. While Fusion of Activation Functions is a promising method, further evaluation is necessary across different container types and port operations to ascertain the broader applicability and generalizability of these findings. The original value of this study lies in its innovative application of FAFs to CDT. Unlike previous studies, this research evaluates the method based on prediction accuracy rather than training time. It opens new avenues for machine learning engineers and researchers in applying FAFs to enhance prediction accuracy in CDT modeling, contributing to a previously underexplored area. 展开更多
关键词 Artificial Neural Networks Container Dwell Time fusion of Activation functions Randomized Search CV Algorithm Prediction Accuracy
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Approximating the Radial Distribution Function of the Electron in a Hydrogen Atom by a Normal Distribution Suggests That Magnetic Confinement Fusion Would Be Less Energy Efficient than Inertial Confinement Fusion
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作者 Motohisa Osaka 《Applied Mathematics》 2024年第9期585-593,共9页
Since the position of the electron in a hydrogen atom cannot be determined, the region in which it resides is said to be determined stochastically and forms an electron cloud. The probability density function of the s... Since the position of the electron in a hydrogen atom cannot be determined, the region in which it resides is said to be determined stochastically and forms an electron cloud. The probability density function of the single electron in 1s orbit is expressed as φ2, a function of distance from the nucleus. However, the probability of existence of the electron is expressed as a radial distribution function at an arbitrary distance from the nucleus, so it is estimated as the probability of the entire spherical shape of that radius. In this study, it has been found that the electron existence probability approximates the radial distribution function by assuming that the probability of existence of the electron being in the vicinity of the nucleus follows a normal distribution for arbitrary x-, y-, and z-axis directions. This implies that the probability of existence of the electron, which has been known only from the distance information, would follow a normal distribution independently in the three directions. When the electrons’ motion is extremely restricted in a certain direction by the magnetic field of both tokamak and helical fusion reactors, the probability of existence of the electron increases with proximity to the nucleus, and as a result, it is less likely to be liberated from the nucleus. Therefore, more and more energy is required to free the nucleus from the electron in order to generate plasma. 展开更多
关键词 Electron Cloud Radial Distribution function Nuclear fusion TOKAMAK Laser
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基于YOLO-BioFusion的血细胞检测模型
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作者 张傲 刘微 +2 位作者 刘阳 杨思瑶 管勇 《电子测量技术》 北大核心 2025年第18期177-188,共12页
血细胞检测是临床诊断中的重要任务,尤其在面对细胞类型多样、尺寸差异显著、目标重叠频繁以及复杂背景时,现有检测模型的精度和鲁棒性仍面临挑战。为解决这些问题,本文提出了一种改进的YOLOv8目标检测模型——YOLO-BioFusion。该模型... 血细胞检测是临床诊断中的重要任务,尤其在面对细胞类型多样、尺寸差异显著、目标重叠频繁以及复杂背景时,现有检测模型的精度和鲁棒性仍面临挑战。为解决这些问题,本文提出了一种改进的YOLOv8目标检测模型——YOLO-BioFusion。该模型通过引入ACFN模块,提高了对细小目标和重叠目标的检测能力;应用C2f-DPE和SPPF-LSK模块增强了多尺度特征的融合与提取,提升了模型的鲁棒性和泛化能力;同时,采用Inner-CIoU损失函数加速了模型收敛并提高了定位精度。实验结果表明,在BCCD数据集上,YOLO-BioFusion的mAP@0.5为94.0%,mAP@0.5:0.95为65.2%,分别较YOLOv8-n提高了1.9%和3.2%。与此同时,计算成本仅为6.8 GFLOPs,展示了其在资源受限环境中的应用潜力。该研究为复杂背景下的血细胞检测提供了一种高效且精确的解决方案。 展开更多
关键词 血细胞检测 多尺度特征融合 损失函数优化 YOLOv8 重叠目标
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Consistent and Specific Multi-View Functional Brain Networks Fusion for Autism Spectrum Disorder Diagnosis
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作者 Chaojun Zhang Chengcheng Wang +1 位作者 Limei Zhang Yunling Ma 《Journal of Applied Mathematics and Physics》 2023年第7期1914-1929,共16页
Functional brain networks (FBN) based on resting-state functional magnetic resonance imaging (rs-fMRI) have become an important tool for exploring underlying organization patterns in the brain, which can provide an ob... Functional brain networks (FBN) based on resting-state functional magnetic resonance imaging (rs-fMRI) have become an important tool for exploring underlying organization patterns in the brain, which can provide an objective basis for brain disorders such as autistic spectrum disorder (ASD). Due to its importance, researchers have proposed a number of FBN estimation methods. However, most existing methods only model a type of functional connection relationship between brain regions-of-interest (ROIs), such as partial correlation or full correlation, which is difficult to fully capture the subtle connections among ROIs since these connections are extremely complex. Motivated by the multi-view learning, in this study we propose a novel Consistent and Specific Multi-view FBNs Fusion (CSMF) approach. Concretely, we first construct multi-view FBNs (i.e., multiple types of FBNs modelling various relationships among ROIs), and then these FBNs are decomposed into a consistent representation matrix and their own specific matrices which capture their common and unique information, respectively. Lastly, to obtain a better brain representation, it is fusing the consistent and specific representation matrices in the latent representation spaces of FBNs, but not directly fusing the original FBNs. This potentially makes it more easily to find the comprehensively brain connections. The experimental results of ASD identification on the ABIDE datasets validate the effectiveness of our proposed method compared to several state-of-the-art methods. Our proposed CSMF method achieved 72.8% and 76.67% classification performance on the ABIDE dataset. 展开更多
关键词 functional Brain Network fusion CONSISTENCY SPECIFICITY Autism Spectrum Disorder
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Disorder structural predictions of the native EWS and its oncogenic fusion proteins in rapport with the function
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作者 Roumiana Todorova 《Advances in Bioscience and Biotechnology》 2012年第1期25-34,共10页
The Intrinsic structural disorder (ISD) of native EWS and its fusion oncogenic proteins, including EWS/FliI, EWS/ATF1 and EWS/ZSG, was estimated by different Predictors. The ISD difference between the wild type and th... The Intrinsic structural disorder (ISD) of native EWS and its fusion oncogenic proteins, including EWS/FliI, EWS/ATF1 and EWS/ZSG, was estimated by different Predictors. The ISD difference between the wild type and the oncogenic fusions found in the CTD is due to the fusion partner, usually a transcription factor (TF). A disordered region was found in the sequence (AA 132 - 156) of the NTD (EAD) of EWS, consisting of the longest region free of Y motifs. The IQ domain (AA 258 - 280), a Y-free region, flanked by two Y-boxes, is also disordered by all used Predictors. The EWS functional regions RGG1, RGG2 and RGG3 are predominantly disordered. A strong dependence was found between the structure of EWS protein and its oncogenic fusions, and their estimated ISD. The oncogenic function of the fusions is related to a decreased ISD in the CTD, due to the fused TF. The Predictors shown that the different isoforms have similar profiles, shifted with some amino acids, due to the translocations. On the bases of the prediction results, an analysis was made of the EWS sequence and its functional regions with increased ISD to make a relationship sequence-disorder-function that could be helpful in the design of antitumor agents against the corresponding malignances. 展开更多
关键词 Intrinsicaly DISORDERED PROTEINS PREDICTORS Relationship Sequence-Disorder-function EWS Oncogenic fusion PROTEINS
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Application of Multiple Sensor Data Fusion for the Analysis of Human Dynamic Behavior in Space: Assessment and Evaluation of Mobility-Related Functional Impairments
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作者 Thompson Sarkodie-Gyan Huiying Yu +2 位作者 Melaku Bogale Noe Vargas Hernandez Miguel Pirela-Cruz 《Journal of Biomedical Science and Engineering》 2017年第4期182-203,共22页
The authors have applied a systems analysis approach to describe the musculoskeletal system as consisting of a stack of superimposed kinematic hier-archical segments in which each lower segment tends to transfer its m... The authors have applied a systems analysis approach to describe the musculoskeletal system as consisting of a stack of superimposed kinematic hier-archical segments in which each lower segment tends to transfer its motion to the other superimposed segments. This segmental chain enables the derivation of both conscious perception and sensory control of action in space. This applied systems analysis approach involves the measurements of the complex motor behavior in order to elucidate the fusion of multiple sensor data for the reliable and efficient acquisition of the kinetic, kinematics and electromyographic data of the human spatial behavior. The acquired kinematic and related kinetic signals represent attributive features of the internal recon-struction of the physical links between the superimposed body segments. In-deed, this reconstruction of the physical links was established as a result of the fusion of the multiple sensor data. Furthermore, this acquired kinematics, kinetics and electromyographic data provided detailed means to record, annotate, process, transmit, and display pertinent information derived from the musculoskeletal system to quantify and differentiate between subjects with mobility-related disabilities and able-bodied subjects, and enabled an inference into the active neural processes underlying balance reactions. To gain insight into the basis for this long-term dependence, the authors have applied the fusion of multiple sensor data to investigate the effects of Cerebral Palsy, Multiple Sclerosis and Diabetic Neuropathy conditions, on biomechanical/neurophysiological changes that may alter the ability of the human loco-motor system to generate ambulation, balance and posture. 展开更多
关键词 Superimposed BODY SEGMENTS Transfer functionS MULTIPLE Sensor Data fusion MUSCULOSKELETAL System
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基于多尺度特征增强的航拍小目标检测算法
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作者 肖剑 何昕泽 +2 位作者 程鸿亮 杨小苑 胡欣 《浙江大学学报(工学版)》 北大核心 2026年第1期19-31,共13页
针对航拍图像小目标检测中存在的检测精度低和模型参数量大的问题,提出兼顾性能与资源消耗的航拍小目标检测算法.以YOLOv8s为基准网络,通过降低通道维数和加强对高频特征的关注,提出自适应细节增强模块(ADEM),在减少冗余信息的同时加强... 针对航拍图像小目标检测中存在的检测精度低和模型参数量大的问题,提出兼顾性能与资源消耗的航拍小目标检测算法.以YOLOv8s为基准网络,通过降低通道维数和加强对高频特征的关注,提出自适应细节增强模块(ADEM),在减少冗余信息的同时加强对小目标细粒度特征的捕获;基于PAN-FPN架构调整特征融合网络,增加对浅层特征的关注,同时引入多尺度卷积核增强对目标上下文信息的关注,以适应小目标检测场景;针对传统IoU灵活性、泛化性不强的问题,构建参数可调的Nin-IoU,通过引入可调参数,实现对IoU的针对性调整,以适应不同检测任务的需求;提出轻量化检测头,在增强多尺度特征信息交融的同时减少冗余信息的传递.结果表明,在VisDrone2019数据集上,所提算法以8.08×106的参数量实现了mAP0.5=50.3%的检测精度;相较于基准算法YOLOv8s,参数量降低了27.4%,精度提升了11.5个百分点.在DOTA与DIOR数据集上的实验结果表明,所提算法具有较强的泛化能力. 展开更多
关键词 目标检测 YOLOv8 无人机图像 特征融合 损失函数
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Bridging the gap:axonal fusion drives rapid functional recovery of the nervous system
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作者 Jean-Sébastien Teoh Michelle Yu-Ying Wong +1 位作者 Tarika Vijayaraghavan Brent Neumann 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第4期591-594,共4页
Injuries to the central or peripheral nervous system frequently cause long-term disabilities because damaged neurons are unable to efficiently self-repair.This inherent deficiency necessitates the need for new treatme... Injuries to the central or peripheral nervous system frequently cause long-term disabilities because damaged neurons are unable to efficiently self-repair.This inherent deficiency necessitates the need for new treatment options aimed at restoring lost function to patients.Compared to humans,a number of species possess far greater regenerative capabilities,and can therefore provide important insights into how our own nervous systems can be repaired.In particular,several invertebrate species have been shown to rapidly initiate regeneration post-injury,allowing separated axon segments to re-join.This process,known as axonal fusion,represents a highly efficient repair mechanism as a regrowing axon needs to only bridge the site of damage and fuse with its separated counterpart in order to re-establish its original structure.Our recent findings in the nematode Caenorhabditis elegans have expanded the promise of axonal fusion by demonstrating that it can restore complete function to damaged neurons.Moreover,we revealed the importance of injury-induced changes in the composition of the axonal membrane for mediating axonal fusion,and discovered that the level of axonal fusion can be enhanced by promoting a neuron's intrinsic growth potential.A complete understanding of the molecular mechanisms controlling axonal fusion may permit similar approaches to be applied in a clinical setting. 展开更多
关键词 axonal fusion axon regeneration nervous system repair nerve injury PHOSPHATIDYLSERINE functional repair axonal transport Caenorhabditis elegans
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一种抗遮挡重叠与尺度变化的行人检测算法
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作者 马晞茗 李宁 吴迪 《现代电子技术》 北大核心 2026年第1期41-48,共8页
针对复杂人群密集场景中因行人目标受遮挡和行人目标尺度不一等因素导致行人检测器检测精度下降、漏检率变高的问题,基于Faster R-CNN算法进行改进,提出一种抗遮挡重叠与尺度变化的行人检测算法。在特征提取环节,设计一种融合注意力机... 针对复杂人群密集场景中因行人目标受遮挡和行人目标尺度不一等因素导致行人检测器检测精度下降、漏检率变高的问题,基于Faster R-CNN算法进行改进,提出一种抗遮挡重叠与尺度变化的行人检测算法。在特征提取环节,设计一种融合注意力机制的循环多尺度特征提取网络,用于学习更为丰富细致的多尺度特征信息,并重点聚焦于关键特征信息,提升网络对不同尺度行人目标的灵敏度;对于损失函数模块,引入斥力损失以降低目标相互遮挡对检测造成的干扰;在后处理环节,设计一种基于遮挡重叠率补偿的非极大值抑制算法,使得实际的抑制阈值能够随着遮挡程度的变化而自适应调整,从而进一步降低密集处行人目标的漏检率。实验结果表明:改进后算法的检测性能更为出色,在CrowdHuman和CityPersons数据集上的检测平均精度相比基准算法分别提升了2.5%和1.9%,对数平均漏检率分别降低了3.5%和3.2%,在TJU-DHD-pedestrian数据集上不同尺度行人目标的对数平均漏检率也得到较为明显的降低,所提算法可以适用于复杂场景中的行人检测。 展开更多
关键词 行人检测 人群密集场景 Faster R-CNN 多尺度特征融合 损失函数 非极大值抑制
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线粒体动力学在骨缺损修复中的作用与机制
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作者 周发达 龙智生 《中国组织工程研究》 北大核心 2026年第23期5906-5914,共9页
背景:线粒体的动态变化如融合、分裂和自噬等,对于保持线粒体的健康稳态和细胞平衡特别重要。越来越多的研究表明,骨缺损愈合过程中这些线粒体的动态变化极其重要,深入研究线粒体动态过程为治疗骨缺损开创了新的可能。目的:探究线粒体... 背景:线粒体的动态变化如融合、分裂和自噬等,对于保持线粒体的健康稳态和细胞平衡特别重要。越来越多的研究表明,骨缺损愈合过程中这些线粒体的动态变化极其重要,深入研究线粒体动态过程为治疗骨缺损开创了新的可能。目的:探究线粒体动力学的作用机制与原理以及在骨缺损修复方面的研究与进展。方法:检索中国知网、万方数据库、PubMed、Web of Science数据库1990-2024年发表的相关文献,中文检索词为线粒体动力学,骨缺损修复,线粒体融合与分裂,骨细胞;英文检索词为mitochondrial dynamics,bone defect repair,mitochondrial dysfunction。对所有检索到的文献按照严格的标准逐一进行筛选、分析及整理,共纳入77篇文献,其中中文15篇、英文62篇,对所纳入的文献进行综合分析。结果与结论:①骨缺损修复受到多种细胞和分子信号通路的精细调控,整个过程是相当复杂的,线粒体动力学在此过程中特别重要,它们能够影响骨细胞功能和骨代谢,进一步促进骨缺损的修复;②未来可以重点深入开展一些关于线粒体动力学分子机制的研究,研发新型纳米靶向颗粒和线粒体临床药物,为线粒体动力学在骨缺损修复的临床应用创造更多可能。 展开更多
关键词 线粒体动力学 骨缺损修复 线粒体自噬 融合 分裂 细胞功能 骨代谢
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改进YOLOv11s的无人机图像小目标检测模型
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作者 牟毅 黄海松 +3 位作者 李宜汀 付盛伟 李科 朱云伟 《电光与控制》 北大核心 2026年第1期51-57,共7页
为解决无人机目标检测中小尺寸、密集目标检测困难及在边缘设备部署困难的问题,提出了小目标检测模型Drone-YOLO。首先,提出了MF-FPN网络,在降低模型复杂度的同时融合高级语义与低级几何特征;其次,为解决小目标、密集目标难以检测问题... 为解决无人机目标检测中小尺寸、密集目标检测困难及在边缘设备部署困难的问题,提出了小目标检测模型Drone-YOLO。首先,提出了MF-FPN网络,在降低模型复杂度的同时融合高级语义与低级几何特征;其次,为解决小目标、密集目标难以检测问题提出了小目标检测头;而后,提出轻量化检测头LSCD,通过共享卷积降低模型复杂度,并利用组归一化提升检测性能;最后,引入Inner-WIoU损失函数,动态调整锚框权重,使模型更专注于中等质量锚框优化,从而提升回归效率与泛化能力。在公开数据集VisDrone2019上进行实验,改进后模型的mAP 0.5达到44.3%,较YOLOv11s提升6.4个百分点,参数量减少67.5%。 展开更多
关键词 无人机 小目标检测 YOLOv11s 多尺度特征融合 轻量化 损失函数
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麻疹病毒血凝素基因助融合(Fusion helper)活性区的定位
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作者 杨克俭 阮力 +2 位作者 孙朝辉 陆柔剑 朱既明 《病毒学报》 CAS CSCD 北大核心 1997年第1期13-18,共6页
在利用PCR方法克隆麻疹病毒L4株血凝素(HA)基因的过程中,获得了一个助融合活性丢失的B号克隆。其氨基酸序列与具有助融合活性的A号克隆相比,有4个位点不同,分别位于96、117、148及543位。通过基因间部分序列... 在利用PCR方法克隆麻疹病毒L4株血凝素(HA)基因的过程中,获得了一个助融合活性丢失的B号克隆。其氨基酸序列与具有助融合活性的A号克隆相比,有4个位点不同,分别位于96、117、148及543位。通过基因间部分序列的交换及定点回复突变,获得了相应位点的突变体。对这些突变体的助融合活性研究发现,117、148及543位氨基酸的改变不影响助融合活性,而当96位脯氨酸定点回复突变为亮氨酸后,B克隆血凝素蛋白获得了助融合活性。提示HA蛋白96位氨基酸是影响助融合活性的一个重要氨基酸。 展开更多
关键词 麻疹病毒 血凝素 基因 助融合活性
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基于特征关注机制的田间杂草检测方法研究
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作者 李祥 田绍华 +2 位作者 朱月浩 庞东林 张心久 《农机化研究》 北大核心 2026年第1期119-126,共8页
现有方法在检测杂草时主要侧重于局部提取能力的提高,没有更好地利用更广泛的语义信息,这在很大程度上影响了识别的准确性。为此,提出了一种基于特征关注机制的田间杂草检测方法。首先,关注杂草的多层图像信息,融合多层语义特征,更高效... 现有方法在检测杂草时主要侧重于局部提取能力的提高,没有更好地利用更广泛的语义信息,这在很大程度上影响了识别的准确性。为此,提出了一种基于特征关注机制的田间杂草检测方法。首先,关注杂草的多层图像信息,融合多层语义特征,更高效地表示关键信息;然后,设计了特征预交互机制,将多尺度特征进行预交互,充分优化深层和浅层特征表示,以便在特征融合时获得更好的特征表示能力;最后,通过使用4层检测单元和杂草交并比损失函数,进一步增强对复杂特征的感知能力,显著提高田间杂草识别的准确性和鲁棒性。3个复杂场景杂草数据集上的实验结果表明,该方法在精确度、召回率和mAP指标上均具有先进的检测效果,在CAW数据集上分别达到了94.1%、95.7%和98.3%,在ACRE-Crop-Weed数据集上达到了93.3%、96.2%和97.4%,在Ronin数据集上达到了96.7%、94.8%和97.9%;mAP指标比其他方法高2.8~10.1个百分点。此外,消融实验也验证了所提方法的有效性。该田间杂草检测方法可为精准除草机械设备提供技术支持。 展开更多
关键词 杂草检测 注意力机制 深度学习 特征融合 特征提取 损失函数
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Location Data Fusion Based on Group Consensus
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作者 李国栋 陈维南 《Journal of Southeast University(English Edition)》 EI CAS 1997年第1期98-102,共5页
A new method of multi sensor location data fusion is proposed.The method is based on group consensus approach, which constructs group utility function (or its density) based on uncertainty of each sensor, and the loc... A new method of multi sensor location data fusion is proposed.The method is based on group consensus approach, which constructs group utility function (or its density) based on uncertainty of each sensor, and the location estimation is obtained based on the group utility function (or its density). The simulation results show that the method is better than those of mean and median estimation, and outlier and sensor failure can not affect the location estimation. 展开更多
关键词 multi sensor DATA fusion UTILITY function GROUP CONSENSUS LOCATION DATA fusion
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Surgical Management of Spondylolisthesis by Pedicular Screw Rod System and Postero-Lateral Fusion
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作者 M. Chaitanya Ankur Mittal +2 位作者 Ramprasad Rallapalli Ravi Teja Y. Siva Prasad 《Open Journal of Orthopedics》 2015年第6期163-174,共12页
Introduction: Incidence of spondylolisthesis in general population is 5% - 7%. No matter what the etiology is, patients usually have significant functional disability. Few studies have investigated the long term effec... Introduction: Incidence of spondylolisthesis in general population is 5% - 7%. No matter what the etiology is, patients usually have significant functional disability. Few studies have investigated the long term effect of posterolateral fusion on functional outcome. Objectives: To study the efficacy of posterolateral fusion in spondylolisthesis especially in terms of functional outcome. Methodology: From July 2010 to June 2012, a total of 86 patients, operated with postero-lateral fusion were followed up and evaluated based on VAS for low back pain, ODI and neurological deficits. Results: Follow up was 83% of original study population (86). Average follow up was 13 months. The mean difference between pre-operative and post-operative VAS at final follow up was 3.5 cms (SD = 2.94);ODI was 28% at 4 months and 36% at 8 months. Claudication pain relieved in all;functional outcome was good in 67%, fair in 27.5% and failed in 5.5%;75% had fusion at an average of 5.5 months. Conclusion: Posteriolateral fusion is still a safe, promising and appealing technique. 展开更多
关键词 SPONDYLOLISTHESIS POSTEROLATERAL fusion functional OUTCOME
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基于改进Res2Net与迁移学习的水果图像分类 被引量:4
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作者 吴迪 肖衍 +2 位作者 沈学军 万琴 陈子涵 《电子科技大学学报》 北大核心 2025年第1期62-71,共10页
针对传统水果图像分类算法特征学习能力弱和细粒度特征信息表示不强的缺点,提出一种基于改进Res2Net与迁移学习的水果图像分类算法。首先,针对网络结构,在Res2Net的残差单元中引入动态多尺度融合注意力模块,对各种尺寸的图像动态地生成... 针对传统水果图像分类算法特征学习能力弱和细粒度特征信息表示不强的缺点,提出一种基于改进Res2Net与迁移学习的水果图像分类算法。首先,针对网络结构,在Res2Net的残差单元中引入动态多尺度融合注意力模块,对各种尺寸的图像动态地生成卷积核,利用meta-ACON激活函数优化ReLU激活函数,动态学习激活函数的线性和非线性,自适应选择是否激活神经元;其次,采用基于模型迁移的训练方式进一步提升分类的效率与鲁棒性。实验结果表明,该算法在Fruit-Dataset和Fruits-360数据集上的测试准确率相比Res2Net提升了1.2%和1.0%,召回率相比Res2Net提升了1.13%和0.89%,有效提升了水果图像分类性能。 展开更多
关键词 图像分类 Res2Net 动态多尺度融合注意力 激活函数 迁移学习
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基于时空交互网络的人体行为检测方法研究 被引量:1
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作者 田青 张浩然 +2 位作者 楚柏青 张正 豆飞 《计算机应用与软件》 北大核心 2025年第4期156-165,共10页
针对现有的人体行为检测方法中,存在特征融合能力较差、时序信息相关性不强和行为边界不明确等问题,提出一种基于时空交互网络的人体行为检测方法。重新设计了双流特征提取模块,在空间流和时空流两个网络之间添加连接层;分别在空间流和... 针对现有的人体行为检测方法中,存在特征融合能力较差、时序信息相关性不强和行为边界不明确等问题,提出一种基于时空交互网络的人体行为检测方法。重新设计了双流特征提取模块,在空间流和时空流两个网络之间添加连接层;分别在空间流和时间流网络中引入改进的空间变换网络和视觉注意力模型;设计基于像素筛选器的特征融合模块,用于重点区域时序信息相关性的计算和两类不同维度特征的聚合;对网络的损失函数进行了优化。在AVA数据集上的实验结果表明该方法在检测精度、速度以及泛化能力上具有优越性。 展开更多
关键词 时空交互网络 人体行为检测 视觉注意力 特征融合 损失函数
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Application of Kelvin Probe to Studies of Fusion Reactor Materials under Irradiation
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作者 罗广南 K.Yamaguchi +1 位作者 T.Terai M.Yamawaki 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第4期2982-2984,共3页
Recently, the work function (WF) changes in metallic and ceramic materials to be potentially used in future fusion reactors have been examined by means of Kelvin probe (KP), under He ion irradiation in high energy... Recently, the work function (WF) changes in metallic and ceramic materials to be potentially used in future fusion reactors have been examined by means of Kelvin probe (KP), under He ion irradiation in high energy (MeV) and / or low energy (500 eV) ranges. The results of polycrystalline Ni samples indicate that the 1 MeV beam only induces decrease in the WF within the experimental fluence range; whereas the irradiation of 500 eV beam results in decrease in the WF firstly, then increase till saturation. A dual layer surface model is employed to explain the observed phenomena, together with computer simulation results by SRIM code. Charges buildup on the surface of lithium ceramics has been found to greatly influence the probe output, which can be explained qualitatively using a model concerning an induction electric field due to external field and free charges on the ceramic surface. 展开更多
关键词 fusion reactor materials work function IRRADIATION
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基于卷积神经网络的轻量高效图像隐写 被引量:3
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作者 段新涛 白鹿伟 +4 位作者 徐凯欧 张萌 保梦茹 武银行 秦川 《应用科学学报》 北大核心 2025年第1期80-93,共14页
基于深度学习的图像隐写方法,因存在模型参数量和计算量大等问题,而面临高参数和计算负载的挑战,为此提出了一种轻量高效的图像隐写方法。首先在编码器和解码器中引入Ghost模块,降低了编码器和解码器的参数量和计算量。其次提出了一个... 基于深度学习的图像隐写方法,因存在模型参数量和计算量大等问题,而面临高参数和计算负载的挑战,为此提出了一种轻量高效的图像隐写方法。首先在编码器和解码器中引入Ghost模块,降低了编码器和解码器的参数量和计算量。其次提出了一个多尺度特征融合模块,用以捕捉多维数据中的复杂关系。最后提出了一个新颖的混合损失函数,可在保持模型不变的情况下提升图像隐写质量。实验结果表明,所提方法在256×256像素的图像上峰值信噪比达到47.59 dB。与目前最优的图像隐写方法相比,所提方法的隐写质量提升1.7 dB,参数量减少77%,计算量减少91%,在隐写质量上有较优的表现,同时模型的参数量和计算量大大降低,实现了模型的轻量高效化。 展开更多
关键词 图像隐写 深度学习 多尺度特征融合 混合损失函数
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