基于肘关节表面肌电信号的负载识别

针对大多数肌电信号只进行特定肢体动作识别而没有对肢体进行外加负载识别的问题,提出一种基于表面肌电信号(surface electromyography, s EMG)的负载识别方法。首先,采用4通道表面电极采集肘关节在不同负载下的s EMG信号;然后,利用时域、频域特征提取方法对s EMG信号进行特征提取构成特征向量;最后,利用支持向量机(support vector maching, SVM)、BP神经网络和RBF神经网络对特征向量进行分类识别。结果表明以时域特征值识别,SVM的识别效果最佳,准确率为96.2%;以频域特征值识别,BP神经网络的识别效果最佳,准确率为87.5%;以时、频域组合特征值识别,RBF神经网络的识别效果最佳,准确率为90.4%。可见通过s EMG信号进行负载识别具有一定的可行性,为s EMG信号的广泛应用奠定基础。     

人体下肢表面肌电信号的检测与分析

人体步行时下肢肌电信号 (EMG)活跃 ,为研究步态周期内 EMG随路况的变化趋势 ,采用了下肢表面 EMG8通道检测装置进行了实验 ,对多人在 6种路况 (或步速 )下行走时的下肢 EMG进行了检测和分析。实验结果表明 ,步行时下肢肌肉活动有一定的规律性 ;各路况信号开始及持续时间、信号绝对值平均、中频等特征值区分明显 ,可以将其应用于智能肌电控制假肢路况模式辨识     

肌电信号分解的一种方法(英文)

肌电信号的分解是根据肌电信号形成的机理 ,还原出构成它的各个运动单位动作电位序列 (MUAPT)的过程 .本文首先采用匹配滤波的方法 ,对组成EMG信号的各个运动单位动作电位 (MUAP)进行检测和提取 .算法能自适应地更新匹配滤波器和标准MUAP模板 ,以跟踪MUAP在发放过程中的缓慢变化 .利用获得的基本MUAP模板 ,根据叠加波形与构成它的各MUAP波形之间面积关系 ,得出可能的MUAP组合 .然后再根据每个MUAP的发放特点 ,采用模糊算法 ,从而得到最终的结果 .还利用模拟肌电信号和真实肌电信号对分解算法进行了实验 ,均取得了令人满意的效果     

基于经验模态分解建模法的肌肉疲劳检测

针对表面肌电信号的非平稳特性,采用自回归(auto regression,AR)模型对表面肌电信号进行分析,对短时间内的表面肌电信号的肌肉疲劳迅速做出判定。首先对表面肌电信号进行经验模态分解,得到本征模态函数和趋势项,然后对趋势项进行零化处理,再对本征模态函数分量进行重构处理,重构后的信号可视为均值为零的平稳信号,最后将去势化的信号建立自回归模型,采用基于该模型的第一个时变参数(first time-varying parameter of auto regression modle,ARC1)作为检测肌肉疲劳灵敏度的快速指标。用疲劳前后的相关特征值的灵敏度波动比(sensitivity to variability ratio,SVR)来表征肌肉疲劳的灵敏度,较平均功率频率对疲劳反应灵敏度要高。该方法通过表面肌电信号对肌肉疲劳检测时,具有时间短、灵敏度高以及将表面肌电信号细微特征信息放大、便于识别等优点。     

采用小波变换和高斯过程的肌电信号模型预测

根据表面肌电信号的生物电信号特点,采用小波变换和高斯过程建模的方法对表面肌电信号进行建模和预测.对非线性的表面肌电信号利用拟合能力强大的高斯过程进行建模,预测效果较好,但所需运算时间长.针对其运算时间长的缺点进行改进,将预处理后的表面肌电信号小波分解,对分解后的系数高斯建模,然后重构.实验结果表明:该改进方法在响应时间和预测误差方面效果明显.     

新型腰背部运动训练系统及其效果检测

针对腰肌劳损、背部疼痛等腰背部疾病高发的问题,设计开发了1种腰背部运动训练系统。依据仿生学原理,通过模仿骑马的"8"字型动作,提出了该新型腰背部运动训练系统的技术方案,对机械结构和控制系统进行了设计。制作了新型腰背部运动训练系统的样机,进行了三维运动检测和表面肌电信号(s EMG)检测实验。结果表明,采用该新型腰背部运动系统进行运动训练时,腰方肌和竖背肌的积分肌电信号(IEMG)和肌电均方根(RMS)振幅为静坐状态时的3倍以上,具备有效调整腰背部肌肉运动特性的功能。     

基于惯性信号与肌电信号的手势识别方法

为解决人体表面肌电信号(EMG)误差较大导致手势识别准确率低的问题,提出了一种将手指尖与关节相对于腰部尾椎位置的惯性运动信号与手臂的EMG进行融合,提取新的手势特征集并利用改进禁忌搜索优化后的反向传播(BP)神经网络分类识别。实验结果表明,该特征集相比于传统的肌电特征集准确率提高了8.5%,优化后的BP神经网络相比于优化前准确率提高了12.33%,手势识别综合准确率可达99.75%。     

OGWE算法及其在表面肌电信号中的应用

为消除多通道表面肌电信号采集时相互间的耦合串扰,提出一种新的处理方法.在权重估计的基础上,以待分离信号采样点数及维数总的最小计算复杂度作为优化因子.将小波变换和优化后的广义权重估计(OGWE)算法结合,利用小波分析降低观测信号中噪声的影响后作为独立分量分析(ICA)输入信号.从量能值、相关系数等多方面对优化算法与Fas...     

基于ADS1298的表面肌电采集系统设计

针对现有表面肌电信号采集方法存在的元器件较多、电路复杂和调试困难等问题,以ADS1298集成模拟前端设计了一种新型s EMG信号采集系统.通过充分利用ADS1298集成的可编程增益放大器、24位高分辨率ADC以及右腿驱动放大器,简化了前端调理电路的设计,使系统的集成度高、体积小、功耗低.     

基于MYO的肌电假肢手控制中手势在线识别系统

表面肌电(surface electromyography,s EMG)信号被广泛应用于临床诊断、康复工程和人机交互等领域中.针对目前控制肌电假肢手的电极成本高、电极佩戴困难以及操作灵活性差等问题,设计一种基于MYO的肌电假肢手手势在线识别系统.通过采集人体上肢前臂的表面肌电信号,在时域上分别提取5种特征值,利用反向传播(back propagation,BP)神经网络分类算法实现对8种手势动作意图的在线实时识别.实验结果证明,利用MYO进行手势识别可以获得较好的识别结果,该系统能够准确识别8种手部动作,平均在线识别率达到92%.     

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.     

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.     

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.     

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.     

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.     

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.     

A computer generator for randomly layered structures

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

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

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.