基于EEMD和LS-SVM的癫痫脑电信号识别

针对癫痫脑电(EEG)信号的非平稳性和非线性,提出一种基于集合经验模式分解(EEMD)提特征并利用最小二乘支持向量机(LS-SVM)的脑电信号分类方法。首先利用EEMD将EEG信号分成多个经验模式分量,得到各阶本征模式分量(IMF),然后提取有效特征,最后用LS-SVM对其进行分类,实验结果表明,该方法对癫痫发作间歇期和发作期EEG的提特征后分类识别正确率达到98%。     

疲劳收缩过程中EMG信号规则度增加的检测

研究了肌肉静态及动态收缩过程中表面EMG信号演化模式的变化,发现了疲劳进程中肌电信号趋于规则性变化的规律,信号的所有规则性演化模式之和（以Dreg表示）的增加反映了该规律.与传统的疲劳指标相比,Dreg在刻画不同人体的肌肉疲劳时变异性更小.此外,基于时域的Dreg的计算可以避免传统频域指标的使用局限性.EMG信号规则度增加的发现,不仅为检测疲劳进程中EMG信号的变化提供了一种新的简易方法,更为以往工作中通过非线性指标（包括熵和复杂度等）来评估肌肉疲劳提供了有力的证据.介绍的信号规则度检测方法同样适用于其他生理电信号.     

Synthesized Multi-Method to Detect and Classify Epileptic Waves in EEG

In order to sufficiently exploit the advantages of different signal processing methods, such as wavelet transformation (WT), artificial neural networks (ANN) and expert rules (ER), a synthesized multi-method was introduced to detect and classify the epileptic waves in the EEG data. Using this method, at first, the epileptic waves were detected from pre-processed EEG data at different scales by WT, then the characteristic parameters of the chosen candidates of epileptic waves were extracted and sent into the well-trained ANN to identify and classify the true epileptic waves,and at last, the detected epileptic waves were certificated by ER. The statistic results of detection and classification show that, the synthesized multi-method has a good capacity to extract signal features and to shield the signals from the random noise. This method is especially fit for the analysis of the biomedical signals in biomedical engineering which are usually non-placid and nonlinear.     

Cutting force and its frequency spectrum characteristics in high speed milling of titanium alloy with a polycrystalline diamond tool

In this paper, a series of experiments were performed by high speed milling of Ti-6.5Al-2Zr-1Mo-1V (TA15) by use of polycrystalline diamond (PCD) tools. The characteristics of high speed machining (HSM) dynamic milling forces were investigated. The effects of the parameters of the process, i.e., cutting speed, feed per tooth, and depth of axial cut, on cutting forces were studied. The cutting force signals under different cutting speed conditions and different cutting tool wear stages were analyzed by frequency spectrum analysis. The trend and frequency domain aspects of the dynamic forces were evaluated and discussed. The results indicate that a characteristic frequency in cutting force power spectrum does in fact exist. The amplitudes increase with the increase of cutting speed and tool wear level, which could be applied to the monitoring of the cutting process.     

基于深度森林的脑电情绪识别研究

为了改善传统脑电情绪识别方法需要对脑电信号进行深入了解,且需要人工提取相关特征的缺点,基于深度森林的表征学习能力对脑电样本的时域与频域数据进行自动特征提取,并融合32通道脑电信号的时域特征向量和频域特征向量,通过级联森林对特征作进一步学习。实验结果表明,该方法对效价二分类预测的准确率达到68.4%,查准率达到66.3%,查全率达到89.9%,F1分数达到76.3%;对唤醒度二分类预测的准确率达到68.2%,查准率达到65.8%,查全率达到91.2%,F1分数达到76.4%。通过与DEAP数据集使用EEG信号给出的二分类实验结果进行对比,基于深度森林的脑电情绪识别方法对未知样本的识别准确率高于DEAP的结果。     

轻度认知障碍患者早期面孔加工N170的研究

目的研究轻度认知障碍患者面孔早期加工的脑机制。方法被试者分为正常老年对照（NC）组和轻度认知障碍（MCI）组,各16名,均为右利手。刺激包括3种卡通面孔（中性、微笑、愤怒）和3种非面孔,要求被试者进行面孔识别任务,同时记录32导脑电。结果①MCI组及NC组均产生了明显的颞-枕区分布的面孔特异性成分N170;②与NC组相比,MCI组N170潜伏期显著延长、波幅降低。结论MCI患者在面孔表情早期加工阶段即出现异常。     

汉语维度形容词“深”语义系统研究

"深"是描述容器内部垂直维度或水平维度的形容词。"深"的语义特征为:方位性、方向性、内向性、容器图式性、底部难以到达性、非易视性,这些语义特征作为始源域投射到相关的目标域产生了各种隐喻义,空间义和隐喻义之间以及各隐喻义之间相互关联形成了一个完整的语义系统。     

Inter-and intra-hemispheric EEG coherence in patients with mild cognitive impairment at rest and during working memory task

Objective： To assess functional relationship by calculating inter- and intra-hemispheric electroencephalography （EEG） coherence at rest and during a working memory task of patients with mild cognitive impairment （MCI）. Methods： The sample consisted of 69 subjects： 35 patients （n = 17 males, n = 18 females; 52-71 years old） and 34 normal controls （n = 17 males, n = 17 females; 51 -63 years old）. Mini-mental state examination （MMSE） of two groups revealed that the scores of MCI patients did not differ significantly from those of normal controls （P〉0.05）. In EEG recording, subjects were performed at rest and during working memory task. EEG signals from F3-F4, C3-C4, P3-P4, T5-T6 and O1-O2 electrode pairs are resulted from the inter-hemispheric action, and EEG signals from F3-C3, F4-C4, C3-P3, C4-P4, P3-O1, P4-O2, T5-C3, T6-C4, T5-P3 and T6-P4 electrode pairs are resulted from the intra-hemispheric action for delta （1.0-3.5 Hz）, theta （4.0-7.5 Hz）, alpha-1 （8.0-10.0 Hz）, alpha-2 （10.5-13.0 Hz）, beta-1 （13.5-18.0 Hz） and beta-2 （18.5-30.0 Hz） frequency bands. The influence of inter- and intra-hemispheric coherence on EEG activity with eyes closed was examined using fast Fourier transformation from the 16 sampled channels. Results： During working memory tasks, the inter- and intra-hemispheric EEG coherences in all bands were significantly higher in the MCI group in comparison with those in the control group （P〈0.05）. However, there was no significant difference in inter- and intra-hemispheric EEG coherences between two groups at rest. Conclusion： Experimental results comprise evidence that MCI patients have higher degree of functional connectivity between hemispheres and in hemispheres during working condition, It suggests that MCI may be associated with compensatory processes during working memory tasks between hemispheres and in hemispheres. Moreover, failure of normal cortical connections may exist in MCI patients.     

藏本《通玄真经》音释考

《道藏》本《通玄真经》的释音有着很高的语料价值。藏本、宋本、铁华馆丛书本三个版本虽略有出入,实出同源。唐徐灵府《通玄真经》音注内容具有多样性特点。元杜道坚《通玄真经缵义》在音注方式上是对徐注的继承和改作,明显地带有自身的特点,但又非囿于吴地方音,反映了宋元时期以通语作注的一种类型。     

二叔丁基羟基甲苯分子印迹聚合物的制备与性能研究

分子印迹技术是近些年发展起来的一种新技术,因其具有构效预定性、特异识别性和广泛实用性等特点而被广泛应用于环境、生物医药等领域,其在食品安全检测中也有重要的研究潜力。分别以丙烯酰胺和二乙烯苯为功能单体和交联剂,制备了二叔丁基羟基甲苯分子印迹聚合物,初步探讨了功能单体用量和洗脱时间对聚合物吸附性能的影响。结果表明,二叔丁基羟基甲苯与丙烯酰胺的比例为1：4时合成的印迹聚合物具有良好的印迹效果。     

基于脑电信号与集成分类器的心理负荷评估

为了精确评估个体心理负荷状态,需要获取目标脑电信号数据,脑电信号是评估脑力负荷变化的重要指标。机器学习和神经网络越来越多地用于脑力负荷分类。利用脑电信号特征可在时域和频域中提取突出信息。因此提出一个结合支持向量机（SVM）与超限学习机（ELM）的混合型脑力负荷分类框架。其中支持向量机作为成员分类器,可在高维EEG特征中查找隐藏信息|超限学习机用于融合成员分类器的输出。将ELM-SVM模型与经典脑力负荷分类器进行比较,得出该模型训练精度准确率为1,且测试精度提升0.1个百分点。     

“再说”的词汇化和语法化

现代汉语中的＂再说＂可以分为动词性短语、动词、连词、助词四类,各有其句法特点和语义表达功能。＂再说＂经历了长期的词汇化和语法化历程并仍处于这一进程中,词汇化和语法化程度跟分布环境及使用频率密切相关,语义经历了由行域向言域的转化,主观性增强,语义突显发生了转移。     

Electric wheelchair control system using brain-computer interface based on alpha-wave blocking

A brain-computer interface （BCI） -based electric wheelchair control system was developed, which enables the users to move the wheelchair forward or backward, and turn left or right without any pre-learning. This control system makes use of the amplitude enhancement of alpha-wave blocking in electroencephalogram （EEG） when eyes close for more than 1 s to constitute a BCI for the switch control of wheelchair movements. The system was formed by BCI control panel, data acquisition, signal processing unit and interface control circuit. Eight volunteers participated in the wheelchair control experiments according to the preset routes. The experimental results show that the mean success control rate of all the subjects was 81.3%, with the highest reaching 93.7%. When one subject＇s triggering time was 2.8 s, i.e., the flashing time of each cycle light was 2.8 s, the average information transfer rate was 8.10 bit/min, with the highest reaching 12.54 bit/min.     

赋体溯源与先秦赋述论（下）

论及先秦赋,有的将《楚辞》中包括《天问》《九歌》在内的全部作品皆划入其中。论及赋的源头,有的认为来自行人辞令,而大部分是据“赋者,古诗之流也”及“赋者,铺采摘文,体物写志”的概念空泛加以推论。本文认为应根据已定型的汉赋的几种体式,分别探讨其源头。实际上骚赋、文赋、诗体赋和俗赋在战国之末都已形成。屈原在西周末年以来诵诗的基础上,吸收楚民歌的特征创造了骚赋和诗体赋。作为赋的主体的文赋,过去学者们或以为出于诸子,或以为出于行人之官,实际上其文本来自议对和行人辞令,但由应用文字而转变为文学的一种形式,同瞍朦的赋诵活动有关。是瞍朦选择有意义的议对和辞令,整齐其语言,使之更便于赋诵,从而促成了赋这种文学体裁的产生。除文献记载之外,先秦时较早的赋体作品中常以师旷为主要人物,也说明这一点。俗赋的题材则取自寓言和传说故事,它的形成同以表演、说笑愉悦人主和贵族的俳优有关。战国时淳于髡所编《晏子春秋》中有不少近于俗赋的作品,有的甚至传至汉代以后,在唐代俗赋作品中也得到反映,便是证明。瞍曚和俳优是先秦时代的专业文艺工作者,他们对赋的形成做出了贡献。     

《聊斋志异》中的“再”“又”“复”“还”简

《聊斋志异》中的“再”“又”“复”“还”用法已经相当成熟,既有对先秦汉语的继承,又有很多的新发展。新发展或与现代汉语相同,或为现代汉语用法之肇端。四者都关涉两个动作,“再”“复”“还”关涉的两个动作主体相同,第二个动作为过去或将来时态,“又”关涉的两个动作主体可同可异,第二个动作为过去或现在时态。四者所关涉的两个动作间的关系分为相同、相反、顺承三种。     

EEG dynamics reflects the partial and holistic effects in mental imagery generation

Mental imagery generation is essential in the retrieval and storage of knowledge. Previous studies have indicated that the holistic properties of mental imagery generation can be evaluated more easily than the partial properties. However, the relationship between partial and holistic mental imagery generations has not been clearly demonstrated. To address this issue, we designed a task to investigate the changes in the spectrum of the electroencephalogram (EEG) during partial or holistic imagery generation. EEG signals were obtained from 18 healthy subjects, and a statistical measure of spectral dynamics between two EEG signals in per frequency band was performed. Additionally, a bicoherence spectrum analysis was used to detect the phase coupling within these two imagery conditions. Our results indicated that EEG of the partial imagery appeared earlier and stronger than that of the holistic imagery in the theta (5–8 Hz) range in a time window around 220 to 300 ms after cue onset, and a slight decrease in the alpha (8–12 Hz) band was observed at around 270 ms. The scalp topography of these changes in the theta and alpha bands distributed overall significantly in the frontal and central-temporal areas. The significant phase coupling within two conditions was remarkable at high frequency. From these results, we infer that there are complex relations between partial and holistic imageries. The generation of partial mental imagery is not a subprocess of holistic imagery, but it is relevant to holistic imagery and requires correct modification from the holistic information.     

Time-frequency analysis of EEG signals evoked by voluntary,stimulated and imaginary motions

In order to investigate the characteristics of sensorimotor cortex during motor execution(ME), voluntary, stimulated and imaginary finger flexions were performed by ten volunteer subjects. Electroencephalogram(EEG) data were recorded according to the modified 10-20 International EEG System. The patterns were compared by the analysis of the motion-evoked EEG signals focusing on the contralateral(C3) and ipsilateral(C4) channels for hemispheric differences. The EEG energy distributions at alpha(8—13 Hz), beta(14—30 Hz) and gamma(30—50 Hz) bands were computed by wavelet transform(WT) and compared by the analysis of variance(ANOVA). The timefrequency(TF) analysis indicated that there existed a contralateral dominance of alpha post-movement event-related synchronization(ERS) pattern during the voluntary task, and that the energy of alpha band increased in the ipsilateral area during the stimulated(median nerve of wrist) task. Besides, the contralateral alpha and beta event-related desynchronization(ERD) patterns were observed in both stimulated and imaginary tasks. Another significant difference was found in the mean power values of gamma band(p0.01)between the imaginary and other tasks. The results show that significant hemispheric differences such as alpha and beta band EEG energy distributions and TF changing phenomena(ERS/ERD) were found between C3 and C4 areas during all of the three patterns. The largest energy distribution was always at the alpha band for each task.     

大学生气质类型与自尊关系探析

选取具有四种典型气质类型的64名大学生为被试,以《自尊量表（SES）》和GNAT测验为工具,探讨气质类型与外显和内隐自尊之间的关系。结果表明：1）气质类型影响外显自尊,其中多血质被试的外显自尊得分最高,胆汁质、粘液质被试次之,抑郁质被试得分最低;2）气质类型不影响内隐自尊。最后,在个性与自我发展的范畴内讨论了这一结果。     

Blind separation of speech signals based on wavelet transform and independent component analysis

Speech signals in frequency domain were separated based on discrete wavelet transform （DWT） and inde- pendent component analysis （ICA）. First, mixed speech signals were decomposed into different frequency domains by DWT and the subbands of speech signals were separated using ICA in each wavelet domain; then, the permutation and scaling problems of frequency domain blind source separation （BSS） were solved by utilizing the correlation between adjacent bins in speech signals; at last, source signals were reconstructed from single branches. Experiments were car- ried out with 2 sources and 6 microphones using speech signals at sampling rate of 40 kHz. The microphones were aligned with 2 sources in front of them, on the left and right. The separation of one male and one female speeches lasted 2.5 s. It is proved that the new method is better than single ICA method and the signal to noise ratio is improved by 1 dB approximately.     

庄蹻入滇与庄豪入滇非一事辨

战国时期楚将庄蹻入滇事件与庄豪入滇事件自来被当成一回事。通过深入、细致地辨析相关历史文献材料,庄蹻入滇与庄豪入滇应为二事,所涉人物庄蹻、庄豪并非一人;庄蹻入滇事件的发生时间在楚威王时,不能改为楚顷襄王时;庄蹻入滇路线之“循江上”完全不同于庄豪入滇路线之“从沅水”,庄蹻途经的楚黔中郡也与庄豪所伐之夜郎国没有关系;庄蹻入滇实为入蜀,庄豪入滇实为入夜郎。