基于特征提取的健美操分解动作图像自适应识别方法

为了解决传统方法容易受运动速率、光照情况、遮挡、复杂背景等的影响,导致识别结果鲁棒性较差的问题,通过特征提取方法研究了健美操分解动作图像自适应识别问题。通过时间能量金字塔把视频序列划分成若干段,得到结果中动作并非全为健美操动作,含大量干扰信息,通过背景消减法对进行健美操运动的人体目标进行提取,进行进一步处理,得到人体轮廓的二值图像序列,求出轮廓外界矩形宽度和高度之比,依据宽高比获取关键帧,通过拉普拉斯法求解相邻差异帧与间的光流,降低背景杂波产生的影响。针对关键帧提取特征向量,通过相似性检测对待识别健美操分解动作图像和提取特征进行匹配,设定相似性阈值,将相似性高于阈值的图像作为识别结果。结果表明：所提方法对单人健美操视频数据库的识别准确率高,仅存在一定程度的混淆;所提方法对含不同场景的复杂数据库的识别准确性和其它方法相比最高。可见所提方法受外界环境干扰小,可保证高识别精度。     

柔性姿态估计和时空特征结合的乒乓球动作视频片段关键帧提取

为了解决传统方法在场景复杂的情况下,因无法保证时间与空间上的连续性,导致乒乓球动作识别错误,影响关键帧提取性能的问题,将柔性姿态估计和时空特征结合在一起,研究乒乓球动作视频片段关键帧提取问题。依据稠密光流对乒乓球动作视频片段进行分段。对单帧图像人体柔性姿态进行估计,通过可分离线性滤波器时空特征点检测方法对乒乓球动作视频图像序列特征点的检测,将时空特征点当成中心建立时空立方体,提取时空立方体的像素建立时空特征。为了保证时间与空间上的连续性,引入时空特征边,得到有时空特征的柔性姿态估计结果。通过直方图相交法求出乒乓球动作视频片段中姿态相似度,计算全部姿态的Hog间差异度,构成差异度矩阵。在当前帧姿态差异度超过阈值的情况下认为当前帧为关键帧。实验结果表明,所提方法针对不同场景的保真率与压缩率一直高于0. 7,处于较高水平;主观评价结果好,可提取合理关键帧。可见所提方法对复杂场景的关键帧提取性能优,主观与客观评价结果好。     

基于多特征融合及Transformer的人体跌倒动作检测算法

为解决跌倒动作的检测和空间定位问题,本文以YOLOv3目标检测算法为基础,提出了一种全新的用于人跌倒动作识别的检测架构.本算法将视频拆分成一系列的图片序列,并在图片序列中指定关键帧.通过3D卷积神经网络提取视频序列中的时间维度特征,2D卷积神经网络提取关键帧中的空间维度特征,经通道融合机制在不同尺度的预测特征层进行通道...     

基于关键帧轮廓特征提取的人体动作识别方法

为了在人体动作识别中获得更加准确的前景分割和防止关键信息的几何丢失,提出一种利用关键帧提取关键姿势特征的人体动作识别方法.由于背景建模和差分获得的前景不准确,利用基于纹理的灰度共生矩阵提取动作轮廓,并对原图像帧进行分割;然后计算人体Blob的能量,选取最大信息内容的帧作为关键帧,关键帧的获取使得特征提取对时间的变化具有一定鲁棒性;在特征分类识别阶段,为了提高分类的准确性,提出使用支持向量机-K最近邻(support vector machine-k nearest neighbor,SVM-KNN)混合分类器完成分类.在Weizmann,KTH,Ballet和TUM 4个公开数据集上实验验证了该方法的有效性.相比于局部特征方法、全局特征方法和关键点方法等,该方法获得了更高的识别率.此外,实验结果表明,该方法在KTH和Weizmann数据集上的早期识别效果优于Ballet数据集.     

基于运动块及关键帧的人体动作识别

为了进行动作识别,需要提取能够充分表征动作的运动、时间、空间及形状信息的特征.本文首先从动作的运动特性出发,采用基于图聚类的方法对人体的运动区域进行分割,并通过计算运动块的熵值选出由运动方向一致的运动点构成的运动块.通过建立混合高斯模型对运动块的时空三维位置及运动方向进行特征表示,得到运动描述符.同时,通过比较前后帧中运动块的变化提取关键帧,然后基于词袋框架进一步筛选关键帧,并采用梯度直方图对动作的形状信息进行特征表示,得到形状描述符.通过线性组合运动描述符及形状描述符,得到充分包含动作的运动、时间、空间及形状信息的联合描述符,并采用最近邻分类器进行动作识别.该算法在KTH和UCF运动数据集上较当前方法取得更好识别效果.     

面向手语识别的视频关键帧提取和优化算法

基于计算机视觉的手语识别技术可以为聋校的双语教学带来很大的便利,而手语识别技术的难点之一在于视频关键帧的提取.根据手语视频关键帧的特点和手语者的手语习惯,提出了一种面向手语识别的视频关键帧提取和优化算法.首先利用卷积自编码器提取视频帧的深度特征,对其进行K-means聚类,在每类视频帧中采用清晰度筛选取出最清晰的视频帧...     

非刚性人体运动动作图像姿态轮廓提取算法

针对人体运动动作图像提取传统方法仅能获取局部最佳解, 提取的特征序列不连续, 导致轮廓提取效果差的问题, 提出一种非刚性人体运动动作图像姿态轮廓提取算法. 首先, 对人体运动动作图像序列中的尺度不变特征变换(SIFT)进行提取预处理, 获取人体特征提取图, 设计一种人体运动序列顺序概率图模型, 以保证特征序列提取的连续性; 其次, 构建人体肢体外观模型, 基于该外观模型采用序列影像高精度轮廓提取算法提取当前人体运动动作帧的轮廓线. 实验结果表明, 该算法能提取连续的特征序列, 提取的人体姿态轮廓精确度较高, 且具有较高的效率和鲁棒性.     

一种基于MPEG-7颜色特征和块运动信息的关键帧提取方法

为了改进现有关键帧提取方法在相邻帧间相似性测度方面的不足,提出一种基于MPEG-7颜色布局特征匹配和块运动信息度量的关键帧选取方法。给出颜色布局特征的提取、相似度计算方法以及利用图像分块计算运动信息的方法,并结合距离累加算法提取视频镜头关键帧。实验结果表明,本方法比基于图像综合特征关键帧提取方法检索性能有明显提高,不易产生冗余和漏检,提取的关键帧能够充分代表镜头的内容。     

基于GEP自动聚类算法的视频关键帧提取方法

视频关键帧提取技术是视频数据处理研究领域的热点研究问题.该文针对现有的镜头边界检测技术不能有效提取关键帧的不足,提出一种基于小波边缘检测算子的自适应分块视频镜头边界检测算法.通过检测视频镜头变化,得到分割的镜头,然后对视频帧提取图像特征,并利用基因表达式编程(GEP)的自动聚类功能对视频帧进行聚类,提出并实现了基于GEP自动聚类的视频关键帧提取算法(KFC‐GEP).实验证明该方法能较好的提取视频序列的关键帧.     

基于非线性知识迁移的交叉视角动作识别

针对一般基于知识迁移的方法对未知视角不可用和难以扩展新数据的问题,提出一种基于非线性模型的无监督学习方法,即基于非线性知识迁移(nonlinear knowledge shift,NKS)的串联特征学习.提取密集动作轨迹,并利用通用码书编码;提取动作捕捉数据模拟点的密集轨迹,产生一个仿真数据的大型语料库来学习NKS,其中,轨迹提取前在视角方向上投影模拟点;再从真实视频中提取轨迹,用于训练和测试表示学习过程的轨迹,利用多类支持向量机分类串联特征.在两大通用人体动作识别数据库IXMAS和3D(N-UCLA)上验证了该方法的有效性,实验结果表明,在IXMAS数据集、不同摄像机情况下,该方法的识别精度高于同类方法至少3.5％,在3D(N-NCLA)数据集、双摄像头情况下,识别精度至少提高4.4％.在大部分动作识别中也取得最佳识别率,此外,该方法的训练时间可忽略不计,有望应用于在线人体动作识别系统.     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that