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1.
医药空瓶在生产过程中瓶身表面会产生大量的气泡缺陷,但现有的方法对医药空瓶表面气泡检测存在各种问题,例如对复杂场景变化的鲁棒性不强,抗噪声干扰能力弱等.针对现有医药空瓶表面的气泡缺陷,提出了一种改进的深度学习目标检测算法RetinaNet对瓶身气泡进行检测.对原始RetinaNet算法中的特征金字塔网络结构进行了优化,在特征融合过程中引入了特征增强模块,用来提高网路对图像语义特征的提取,增强网络特征提取能力.为了减少模型的参数数目和计算时间,考虑到空瓶表面气泡均为小目标缺陷,去掉原始特征金字塔网络中用于检测大目标的网络结构,提高了算法检测速度.通过对标准的ResNet50网络进行重新组合,并引进了膨胀卷积模块,扩大特征图感受野,提高了模型检测的精度.通过在注塑空瓶数据集上对本文的方法进行了验证,其准确率为99.72%,漏检率为0.12%,误检率为016%,mAP为99.49%,相比原始的RetinaNet的mAP提高了接近2.4%.  相似文献   

2.
无人机技术的不断成熟,使得搭载高效视觉系统的无人机应用也更加广泛。针对无人机航拍图像中小目标较多、分辨率低等原因导致的检测精度不高的问题,提出了一种改进RetinaNet的无人机航拍目标检测算法。算法针对特征图中小目标信息提取不足的问题,设计了多阶段特征融合方法,并将其与注意力机制串联设计了特征挖掘模块,可以在浅层特征图中融入深层的语义信息,丰富小目标特征;设计了基于中心点检测的无锚框(Anchor-free)方法,网络通过对中心点的回归来定位目标,而不是通过固定大小的锚框去匹配,这样做可以使网络对小目标的回归更加灵活,提高了算法的整体性能;且通过深度可分离卷积方法对网络进行轻量化设计,以压缩模型大小并提高检测速度。实验结果表明,改进算法较原RetinaNet算法平均精度提升了8.5%,检测速度提升了6帧/s,且与其他先进算法相比也具有性能优势,达到了检测精度与检测速度的均衡。  相似文献   

3.
在合成孔径雷达图像舰船目标检测中,由于背景复杂多变,传统的基于人工特征的目标检测方法效果较差.基于深度学习中的单阶段目标检测算法RetinaNet,结合合成孔径雷达图像本身特征信息较少的特点,采用了多特征层融合的思想,改进了网络特征提取能力,提出了相适应的损失函数的计算方法.采用SAR图像舰船目标检测数据集(SSDD)对网络进行训练,并通过样本增强和迁移学习的方法提升算法的鲁棒性和收敛速度.通过实验与其他基于深度学习的目标检测算法所得结果进行比较,结果表明本算法具有更高的检测精度.  相似文献   

4.
基于改进的Adaboost算法在 网络入侵检测中的应用   总被引:2,自引:0,他引:2  
网络入侵检测是一种基于网络行为特征的检测技术.近年来,作为信息安全领域中的研究热点,网络入侵检测发展迅速.针对传统入侵检测算法对于数据特征提取较慢的问题,本文提出了基于信息熵理论的免疫算法来提高特征提取速度.为了进一步提高分类精度,本文对Adaboost分类方法进行了改进,在分类过程中判断噪声数据,并对噪声数据的权重进行调整,从而缓解了Adaboost算法的过度拟合.通过对KDD CUP 99数据的实验结果表明,本文方法可以提高免疫算法在特征提取方面的收敛速度,并能有效地提高入侵检测率.  相似文献   

5.
针对现有算法在行人目标检测中存在精度低、速度慢、算法鲁棒性有限的问题,提出了一种基于深度神经网络目标检测算法YOLOX-L改进的行人目标检测算法YOLOX-H.使用改进型的主干特征提取网络HarDNet85替换原有的CSPDarkNet53,新的主干特征提取网络相较于原有的网络具有更强的特征提取能力以及更快的速度,同时提升了网络检测较大目标的能力.在HarDNet85卷积神经网络中引入了Softplus激活函数提升算法的检测精度,构建了CityPersons、PRW、ETHZ和MOT17多场景的联合数据集,以提升网络对于行人目标检测的鲁棒性.在联合数据集上的实验表明:YOLOX-H相比于YOLOX-L,每秒检测帧数(FPS)提高了32.95%,检测精度提高了3.1%,大目标检测精度提高了6.9%.  相似文献   

6.
为实现复杂场景下多尺度仪表检测,提出了一种基于注意力机制的视频多尺度仪表检测算法。首先,利用基于空间注意力机制的特征提取网络,建模特征的长距离依赖,增强特征的表达能力;其次,提出了一种自适应特征选择模块(Adaptive Feature Selection Module, AFSM),对不同阶段的特征图进行权重调整,增强网络对多尺度目标的检测能力。在自建的仪表数据集上进行了实验。实验结果表明,相比较原来的Faster RCNN方法,所提出方法的检测精度提高了7.6%;与对比方法相比,检测精度也能达到95.4%。在对实际仪表监测视频的测试中,检测结果以及速度能够满足实际需要。所提方法通过改进特征提取网络和特征选择操作,增强了特征表达能力,有效降低了虚警,提升了网络对多尺度目标的检测性能。  相似文献   

7.
乳腺钼靶X线摄影是诊断乳腺疾病的有效手段,计算机辅助诊断系统在乳腺肿块检测中起着重要作用,针对检测过程中易出现漏检、误检导致精度不理想的情况,提出了一种改进的RetinaNet乳腺肿块检测算法.首先,在RetinaNet的基础上对特征提取部分进行改进,在每个残差块中引入多光谱通道注意力机制,使网络能更加关注到目标区域;然后,在特征融合部分,以两种不同方式添加一条自底向上的路径,并通过横向连接最终实现深浅层特征的双向融合,加快浅层信息流通,使得到的特征信息更加丰富.实验表明:改进后的算法在乳腺钼靶图像的肿块检测中具有良好的检测效果,既减少了漏检率,平均精度也提升了3.2%,并且相比其他出色的检测算法,也具有一定的优势.  相似文献   

8.
针对毛巾织物瑕疵检测中存在的小目标瑕疵漏检率高、形变尺度大的瑕疵检测精度低以及模型检测效率不理想等问题,提出一种基于YOLOv4网络的轻量化毛巾织物瑕疵检测方法。采用轻量级网络Ghost Net重构主干特征提取网络,以降低模型运算量,提升检测速度;在深层特征提取网络中引入结合空洞卷积和SoftP ool的DS-CBAM模块,扩大感受野的同时保证特征图分辨率并提高模型对毛巾织物瑕疵特征的提取能力;根据各类毛巾织物瑕疵正负样本不平衡的数据特点,引入难易样本聚焦参数和正负样本平衡参数对损失函数进行优化,降低样本失衡对检测性能的影响;采用改进度量距离的K-means算法自适应生成适合毛巾织物瑕疵尺寸的先验框,提高先验框和毛巾织物瑕疵目标的匹配度。研究结果表明:改进后的模型在毛巾织物瑕疵数据集上的检测精度要优于原YOLOv4和其他主流检测算法,综合类别平均精度达到92.14%,检测速度达到49.98帧/s,分别比原模型提高了5.31%、22.83%,有效平衡了检测精度和检测速度之间的关系。  相似文献   

9.
无人机、车载识别等边缘设备应用日益增长,对模型参数量、检测速度以及精度提出了进一步的要求。为了提高目标检测在这些领域的项目落地能力,提出一种可堆叠重校准特征金字塔模块以及改进的SR-YOLOv3目标检测网络,使用对边缘设备友好的主干网络作为特征提取网络,通过堆叠轻量的金字塔模块,在减少参数数量的同时,提高检测精度及速度。在公开的目标检测数据集PascalVOC上进行性能评估,实验结果显示,该改进算法的参数量有明显下降,且计算速度得到提升。  相似文献   

10.
针对检测模型参数量大,难以在嵌入式设备上部署等问题,设计了一种改进的YOLOv4目标检测算法.该算法使用轻量化的MobileNetV1替换CSPDarketnet53主干特征提取网络,并将后续网络中的3×3卷积替换为深度可分离卷积,极大地减少了模型的参数量;在检测头加入NAM注意力模块,增强网络对细节信息的提取能力;采用SDIoU Loss作为边框回归损失,在加快收敛速度的同时提高了检测精度.实验表明:与YOLOv4-CSPDarknet53相比,改进算法在PASCAL VOC07+12数据集上训练出来的模型大小为47.19 M,约为原来的五分之一,FPS提升了40(f/s),mAP提升了2.4%.与YOLOv4-Tiny、YOLOv5s、YOLOv7等目标检测算法相比,具有兼顾检测速度与精度的特点.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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