共查询到20条相似文献，搜索用时 203 毫秒
1.
LIU Yu hong XIE Zheng xiang XIONG Xing liang WANG Zhi fang LI Hong WANG Ying 《保鲜与加工》2008,(12):1376-1380
A new quantitative analysis method to describe the dynamic variation of electroencephalogram (EEG) signals was proposed. Based on the Fourier transformation, the method is called Fourier multi resolution analysis (FMRA). FMRA decomposes the frequency domain with a binary system and can resolve EEG signals into the basic rhythms of the four waves to study the dynamic characteristics of EEG signal rhythms. FMRA has clear physical meaning, and can obtain more information than wavelet multi resolution analysis does. FMRA can extract perfectly the rhythmic characteristics of EEG signals in the time and frequency domains. 相似文献
2.
EEG signal is a kind of very complex non stationary signal. It is of important clinical values for using EEG most efficiently to distinguish all kinds of components in EEG or getting needed components to judge some pathology features effectively. The phase moving of the system can change the relative phase relation between the components in the inputed signal, so there can be a great change of the feature in time domain of inputed signal. The FRR and RRF digital filtering methods and their realization are discussed. By using these methods, the system can be of the feature of zero phase error, and the filtering of EEG signals with zero phase error can be realized. Based on the definition of sleep spindles, we can detect sleep spindles in time domain directly by using digital filtering with zero phase error. 相似文献
3.
The signal of brain activity is a non-stationary random signal including lots of physiology and disease information, which is of important action for doctors to judge pathological changes in brain. So the analysis and process of the EEG signals are always attended. In this paper, the authors take account of the time-frequency localization of wavelet transform and use multiresolution wavelet transform to detect EEG abnormal rhythms. The signals of different scales after EEG signals are transformed by multiresolution wavelet transform not only reflect the frequency information of the signals, namely the more great scale is the lower of the frequency of the signals,but also reflect the time information of the signals, namely EEG state at that time. The test results indicate that the abnormal rhythms of the EEG signals can be detected effectively if right wavelet basis is selected. 相似文献
4.
EEG spot-recording for clinical patients in the bed is always advocated due to easing patients and making them comfortable. But EEG signals recorded in the ward exposed to various noisesand interference is less effective in the EEG analysis. Atemporal-spatial filter is designed for noise removing of clinical EEG signals, the first filtering is temporal filtering using band-pass filter, and the second filtering is spatial filtering with ICA-based spatial filter. Experimental results indicate that various noises and interferences, such as power interference, blinking, eyes movements, muscle moments, ECG artifacts, etc., are removed effectively, individually or simultaneously. 相似文献
5.
The complex non-stationary signals are most often used in modem radar and communication systems. It must perform the tasks of envelope detection and intra-pulse feature analysis for radar pulse classification and identification. Time-frequency analysis is an effective tool for modem signal processing, and often applied to analyze and process non-stationary signals. Several methods of time-frequency analysis are presented, reconnaissance are also discussed and simulated. Simulation results show the and their applications in the radar signal effectiveness of these methods. 相似文献
6.
Pan Jun Zhou Shouchang Huang Shanglian 《保鲜与加工》1997,(1):88-91
After studying the meaning of EEG signal processing using systems theory,the basic difficulties of the research on the EEG system and signal analysis are given,showing that it is hard to build model of the EEG system and signal.Hence,we introuduce the method of reconstructing the attractor in state spaces.Through the analysis of some experiments,the meaning of the presented method has been discussed. 相似文献
7.
Liu Guixiong Miu Xiue Zhong Xianxin 《保鲜与加工》1997,(4):21-24
The effect on performance of network compensating technique by identifying and processing of signals is studied.And the error function caused by processing signals in time domain is derived,the method that can reduce errors is also proposed. 相似文献
8.
The bursts of 40HzEEG are a reliable indicator of the " focused arousal ". It hasan active significance in diagnosis of cognitive dysfunction.But, the bursts of 40 Hz EEG are seriously interfered by the high amplitude broad-band EMG signals from the scalp. It causes the difficulty of detection, This paper give a new method uf the combination of threshold extraction in frequency domain and neural network pattern recognition to realize the effective detection of 40 Hz EEGbursts , and reports the mean peak power of the 40 HZ EEG bursts for 11 subjects and analyses theirthinking states, The reaults indicate that the method given in this paper can be used feasibly and support the theory given by D,E, Sheer. 相似文献
9.
The article focuses on the method of noise cancellation for EEG signal. The method of notch filter is discussed. According to the frequency of noise and the principle of notch filter, the design result of the notch filter and the denoised signal are presented. Then, the analysis of EEG signal are proposed based on wavelet transform (WT) and noise cancellation using WT. Wavelet transform is a multi-resolution time-frequency analysis method. It can decompose mixed signal into signals at different frequency bands. The EEG signal is analyzed and denoised using WT, then the results are presented respectively. Comparing the experiment results shows that WT can detect and process noise in the EEG signal effectively. 相似文献
10.
In the measurement of EEG signals ,the pre - amplification electrical signal of brain is the most importantant and key link. Whether the design is excellent or inferior is related to the electrical signal detection system of brain directly. The design of this circuit has been paid attention to by domestic and international expert all the time. On the basis of existing biological electricity amplifier which is studied, the authors consult the electric amplifier circuit of living beings designed , such as reference , improve and design a new-type and high performance electrical signal characteristic of brain in . The circuit has prevented the traditional design from enlarging the miscellaneous simulation of the circuit and straining the wave link, otherwise, this circuit is of simple structure , low cost, and convenient debugging. The paper has detailed theoritic analysis and experimental results to prove this circuit, which offered a new train of thought for reseach and development of brain electrical amplifier and other faint biological electricity amplifiers . This curcuit has be expected to win extensive application. 相似文献
11.
12.
CAI Jing zhi 《保鲜与加工》2003,(4):93-95
With the development and application of information and internet and virtual instrument technology ,the virtual globular company based on internet arises .To study remote state monitoring, remote fault detection and diagnosis about large scale, complicated and integrative equipment become very important. In the whole fault diagnosis system , the detecting ,data acquisition is original ,processing; transform and extracting features with the signal detected is a key factor. The theories and methods used in mechanical fault diagnosis is stated. The application of signal process and its feature extracting methods is introduced which are time domain, frequency domain and time frequency domain analysis, in state monitoring and fault diagnosis with its signal analysis. The processing method of random time variant special signal is given also. 相似文献
13.
仪器分析是地方本科院校中化学、生物科学、食品、环境等专业开设的必修课程。从仪器分析教学现状及存在的问题入手,探讨了仪器分析教学改革的新思路,包括:针对不同专业调整教学内容,突出专业实用性和科学性;改进教学方法与手段及其他现代教学理念。在实验教学方面,着力更新实验内容,开设设计性自主实验,强化实验技能,以提高学生科研能力,立足地方经济,培养优秀的创新型、应用型人才。 相似文献
14.
在收集整理2007—2009年农产品加工业课题数量、专利数、科技活动人员数量、有科技机构大中型加工企业所占比例等8项反映产业科技支持能力指标数据的基础上,通过比较新疆和其他地区工业企业、新疆大中型与小型农产品加工企业、新疆和国内农产品加工企业科技支持能力平均水平的差异性,对新疆农产品加工企业的科技支持能力现状进行了系统分析。同时,依据比较分析结果,结合新疆产业现状,提出增强我国农产品加工企业科技支持能力可行性建议,以期为新疆农产品加工企业科技支持能力的进一步提升奠定基础。 相似文献
15.
Extracting features from biomedical signals to provide some decision support for medical diagnoses is an important aspect in the development of biomedical engineering.Analyzing power spectra of pulse signals for 15 heroin addicts and 15 healthy persons and calculating the power distributions on specified frequency bands for every power spectrum based on spectral estimation in this paper,we find that the significant difference of power distributions exists between the heroin addicts and the healthy persons.A primary criterion is also obtained,upon which the 13 cases of 15 heroin addicts are identified.The research result of this paper shows that the frequency domain analysis for pulse signals of heroin addicts is really an effective method. 相似文献
16.
Original signals can be effectively estimated from their linear mixed signals by independent component analysis (ICA), even though their frequency components are overlapped, which provides a way to estimate the faint electrophysiological signals. And many researchers who study biomedical signal processing have paid great attention to the technique. We discuss the ICA model and the implement of a fixed-point fast ICA algorithm based on negentropy criterion. With the algorithm, we availably pick up the simulated visual evoked potential (VEP) from the mixing signals. 相似文献
17.
In this paper,the theory of 40 Hz EEG bursts is firstly used to judge whether thesubjects cooperate with us or not,and to determine the segments which can be processed for the studyof chaotic states of EEG signals.The theory,the realization of detecting method and the practiceapplication of 40 Hz EEG bursts are studied. 相似文献
18.
试验设计与数据处理课程教学改革初探 总被引：1，自引：0，他引：1
针对试验设计与数据处理课程教学中存在的问题,结合教学实践,从教学方法、教学手段、培养学生解决实际问题能力和改革考核方式4个方面,探讨了课程改革的方法和途径。 相似文献
19.
Brain computer interface(BCI) is an EEG based communication and control system between human and computer or other electric devices, which does not depend on the brain's normal output channels of peripheral nerves and muscles. It is a novel kind of human interface, may have applications in rehabilitation, control and other fields. The developming speed of brain computer research in recent years is high. Methods of how to use P300, SSVEP, ERS/ERD, SCP, spontaneous EEG and implanted electrode to realize BCI are introduced. Characteristic and limitation of different methods are discussed. Status, problems and application prospects of BCI technology are also included. 相似文献
20.
The large-span structure requires wind vibration analysis when computing the wind load;however,the formula in current code on wind vibration coefficient can hardly be applied in large-span structure,making its computation difficult and troublesome.This paper makes wind vibration analysis on the large-span curtain wall combined with certain engineering background in the methods of both time domain and frequency domain,and then the derived results are compared.The analytical results demonstrate identical distribution and contiguous numerical value of wind vibration coefficient concluded from the two varied methods;furthermore,even if the method in time domain is higher in computational complexity,more data on the response of structure under wind can be obtained,which provides reference for the theoretical analysis and engineering design. 相似文献