改进深度可分离卷积的SSD车型识别

针对现有车辆识别方法对于车型实时识别能力不足的问题,提出一种改进的深度可分离卷积的SSD(single shot multibox detector)算法用于车型识别研究.首先,利用深度可分离卷积网络进行特征提取,并引入反残差模块来解决因通道数少、特征压缩导致的准确率下降问题.其次,以车辆的刚体特性为依据,重新设计区域候选框,减少模型参数运算量.最后,在BIT-Vehicle数据集上进行消融实验来对比不同网络模型性能差异.结果表明:改进的深度可分离卷积的SSD车型识别方法有更好的车型识别效果,可以达到96.12％的识别精度,检测速度提高至0.078 s/帧.     

基于改进YOLOv5s的轻量化交通灯检测算法

针对目前交通灯检测算法网络模型参数量过大、实时性差的问题,提出了一种基于改进YOLOv5s的轻量化交通灯检测算法.首先,用轻量化网络MobileNetv3替换原主干网络并引入注意力机制,在对检测精度影响不大的前提下降低模型参数量;然后,使用深度可分离卷积替换颈部网络中的传统标准卷积,进一步降低模型参数量;接着,针对交通灯尺度小的特点,删除检测大目标的检测层;最后,改进边框回归损失函数,提升边框检测精度.同时,为了能实时部署在嵌入式平台,该算法对网络进行通道剪枝实现模型压缩和加速.实验结果表明,该算法在嵌入式平台NVIDIA Jetson Xavier NX上能达到48.1帧/s的检测速度,相比原始YOLOv5s牺牲了1.5%的mAP,但是该模型体积压缩了54.3%,检测速度提高为原来的2.6倍,可以满足在交通道路中实时对交通灯检测的需要.     

面向边缘计算的轻量化外力破坏目标检测算法

针对在复杂边缘计算场景下外力破坏目标检测识别精度低与实时性差的问题,提出YOLO-ERFA轻量化目标检测算法。该算法采用跨阶段残差结构的CSPDarkNet53-Tiny作为特征提取网络,在保证模型轻量化的同时提高检测准确率;在此基础上,通过改进空间金字塔池化并融合高效通道注意力机制构建特征增强层以提升模型精度和对多尺度目标的检测能力,并在训练阶段使用改进的Mosaic算法增加样本背景虚化以提高模型在复杂场景下的抗干扰能力。实验结果表明,该方法在测试集上检测平均准确率达到了91.58%,在Jetson TX2平台推理速度达30 FPS,且模型内存大小仅为26.50 MB,提高了算法在边缘计算设备上部署的可行性。     

融合改进帧差和边缘提取算法的运动目标检测

针对帧差算法检测运动目标存在的目标边缘缺失和空洞的问题,提出一种将改进帧差和基于改进Canny算子的运动目标边缘提取方法相融合的运动目标检测算法.首先,使用帧差法快速检测变化区域,并通过面积阈值判断是否进行当前帧的检测以提高算法实时性;其次,在运动目标边缘提取中,提出一种基于改进Canny算子的运动目标边缘提取方法提取...     

基于深度学习的铁路实例分割研究

为了提高铁路图像分割精度使其可作为铁路无人驾驶及设备安全、快速、准确检测等工作的基础视觉任务,在经典的MaskRCNN实例分割网络架构基础上,设计了一个新的特征提取架构DseNet,组合得到了DseNet-MaskRCNN.铁路边缘处的精度对实例分割有着重要的精度影响,在网络架构上着重强化了图像边缘处的精度.实验结果表明该网络架构能够快速的对铁路区域进行识别分割.在实验中单张图像处理速度可达15帧/秒,实例分割精度可达93.8％.     

基于E-HRNet的路面破损区域识别方法

针对现有路面破损区域识别方法识别效率低、泛化性能差等问题,提出了一种基于深度高分辨率网络HRNet的路面坑槽和裂缝识别方法 .采用车载单目相机实地采集路面坑槽和裂缝图像,并对图像进行预处理和标注,生成路面破损数据集.在原HRNet基础上,对其网络特征提取层的4个不同分辨率表征分别融合改进的卷积注意力模块,形成E-HRNet网络模型.为了提高EHRNet模型的推理速度,对其各步骤中不同分辨率分支的残差层数进行了优化,并采用联合损失函数对该模型进行监督训练.试验结果表明：E-HRNet网络模型对路面坑槽和裂缝区域分割的平均像素精度和平均交并比分别达到了94.53%和88.31%,与原HRNet网络模型相比,平均像素准确率增加了6.53%,平均交并比提升了5.38%,平均类别准确率提高了1.39%;模型检测帧率提高了30.3%,而模型体积则减少了42.6%,可满足模型轻量化和实时检测的需求;与DDRNet、DeeplabV3+等同类模型相比,E-HRNet网络模型对坑槽和裂缝区域的分割精度更高,有效地避免了漏检、误检以及边界模糊等问题的出现,具有更好的实时性和泛化性.     

R-YOLO轨道人员目标检测模型

针对现有铁路人员入侵识别准确率不高、实时性较差的问题，在YOLOv4模型的基础上提出一种R-YOLO轨道人员目标检测模型。首先，用轻量级骨干网络ResNet50代替原有的CSPDarknet53网络，利用深度可分离卷积替代PANet中的标准卷积，减少网络层数以及模型体积，加快模型的识别速度。其次，在加强特征提取网络的3个特征层分别加入有效通道注意力模块，采用K-means++聚类算法重新对数据集进行聚类和分析，提高目标检测模型的精度；在模型训练方面，采用迁移学习和混合数据集联合训练，解决人员识别精度不理想以及误检漏检等问题。最后，利用R-YOLO轨道人员目标检测模型对真实铁路人员入侵数据集进行测试。结果表明，R-YOLO模型在真实铁路人员入侵数据集上的平均识别精度达到了92.12%,较传统YOLOv4算法高出1.89%,帧速率由38.74 f·s^-1提升到47.73 f·s^-1。R-YOLO模型部分解决了铁路入侵人员误检漏检问题，提高了铁路人员入侵识别的实时性和准确率，为铁路安全运行提供了保障。     

一种面向移动端应用的实时目标检测算法

针对目标检测算法部署在移动端存在内存消耗大、精度低等问题,在NanoDet模型的基础上提出一种引入改进注意力机制的轻量级目标检测网络。首先,设计通道双池化及空间双向拆分的注意力模块,在尽可能不增加计算消耗的同时加强网络对感兴趣区域的关注能力;其次,引入空洞卷积及Mish函数增加网络的感受野及特征判别能力,并缩减冗余的降采样单元结构以加快网络的实时性;最后,在MS COCO2017数据集及安卓设备上的实验验证可知,本文算法在少量模型参数下提高了检测准确率,并保证30帧/秒的移动端检测速度,效果优于YOLO系列等轻量级网络。实验结果表明,本文算法参数量较YOLO系列模型参数量更低,更适合移动端和嵌入式设备的实时目标检测场景。     

基于改进YOLO v5的城市树木检测

针对城市道路环境复杂、草坪树木密集等引起的树木误检、漏检以及模型较大不易部署在边缘计算设备上等问题,提出一种基于改进YOLO v5的城市树木检测算法.算法引入融合注意力机制的双向加权特征金字塔结构BiFPN-ECA,减少冗余语义特征,增加特征融合网络对关键特征的关注度,提升特征融合质量;利用GSConv卷积替换Neck部分的密集卷积,提升特征提取能力并减少运算量;引入SIoU损失函数,通过加入向量角度这一惩罚项,减少与距离相关的变量,降低回归自由度,加快网络收敛,进一步提升回归精度.采集城市常见绿化树木的图像和视频,建立城市绿化树木样本集进行模型对比试验.试验结果表明,本文方法比初始YOLO v5模型的平均精度均值提升了5%,模型参数量减小为原来的50%,模型的帧率提升了5帧/s,兼顾了检测精度和实时性.     

连续语音的三音子DDBHMM识别方法

针对目前连续语音识别中广泛使用的齐次HMM(hidden Markov model)模型识别精度低的现状,该文提出了三音子DDBHMM(duration distribution based HMM)识别方法。根据汉语的特点,设计了适用于连续语音识别的三音子。描述了识别中使用的MLSS(most likely statesequence)准则。设计了识别网络并阐明了用于三音子识别的帧同步识别算法。将三音子DDBHMM识别方法与三音子齐次HMM识别方法和双音子DDBHMM识别方法进行了实验对比,结果表明:采用三音子DDBHMM可以使得识别错误率分别下降0.95%和2.29%。说明该方法能够显著地改进连续语音识别性能。     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

A computer generator for randomly layered structures

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

An Index mechanism for multi-scale view in spatial databases

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.     

Jane Eyre——A Feminist In The 19th Century

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-