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1.
This paper puts forward an improved fast-LADT arithmetic in application of electrocardiogram(ECG) compression.The arithmetic has much less mathematical operation and much easier to be implemented in hardware.With the artificial and experimental verification,it turns to be that the arithmetic keeps rather high compress ratio,has the advantages of small distortion and has the nicer results in real tine.The hardware system of ECG data compression is designed,implements the improved fast-LADT arithmetic,the experiment of ECG data compression also has been carried out,and the experiment results prove the validity of the arithmetic.  相似文献   

2.
It's necessary to process position and gesture of rocket on real time within the flight of rocket. This work should base exact data. But much noise has been found in the data and the noise recognize is regarded as a focus. A speedy online arithmetic recognizing noise is proposed based on wavelet transform. The computing complexity measured by time of this arithmetic is a constant which is greatly reduces the works of calculation of wavelet transform. It can recognize the noise fast when the signal is gathered. The applications in these problems show that the effective arithmetic satisfies the needs of real time and can handle the real time data measured in other yields.  相似文献   

3.
汽车转弯自动照明控制系统数据采集滤波方法   总被引:1,自引:0,他引:1  
为了减少汽车转弯自动照明控制系统数据滤波处理中的延时,在滑动中值滤波方法基础上,提出了一种带补偿的限幅滑动中值滤波算法,通过补偿的方式跟随信号的变化趋势。该算法通过2个步骤完成滤波,先对数据进行带补偿方式的限幅处理,再进行滑动中值滤波处理。该算法综合了滑动中值滤波法的实时性以及限幅滤波法对偶然性干扰滤除的有效性,实现更准确的滤波。仿真与实测结果表明,与滑动中值滤波方法相比较,改进后的算法滤波能够实时地滤除数据中的干扰,处理时间可减少62%,滤波效果较好,且速度信号的数据滞后时间较短,实时性较高,满足系统设计要求。  相似文献   

4.
The postharvest handling chain is characterised by temperature conditions that are generally not constant throughout the chain. On top of this, postharvest research is dealing with large sources of biological variation. This paper outlines a general model approach of how to account for the propagation of biological variation when analysing experimental postharvest data gathered at dynamic temperature conditions. The proposed technique was applied to experimental data on colour change of tomatoes cv. ‘Tradiro’. The previously developed multivariate stochastic approach was combined with a transformation of real time into physiological time to account for the effect of dynamic temperature conditions. The developed model has the capability to describe the complex batch behaviour showing propagation of biological variation in tomato colour as a function of time and dynamically changing temperature during postharvest storage. This makes the current approach extremely suitable for application in real life situations when evaluating and optimising a logistic handling chain.  相似文献   

5.
Several kinds of microphone developed via silicon Micro Electro Mechanical System (MEMS) processes in recent years are investigated in this paper. The analysis and research of the merits and demerits of them show that: these conventional microphones mainly function as acoustic electric converters; the filtering against noise is implemented by a special filter circuit or a digital filter. Therefore, a design method for silicon micro array filter microphone is presented, where the filtering is achieved while converting signals. The effects of damping, silicon reed number and sensor element pair on dynamic characteristic are discussed; it follows that: Increasing damping can reduce microphone's sensitivity, while increasing silicon reed number can improve the sensitivity curve, furthermore, the implementation of the filter function is simultaneous with acquiring of the noise signal.  相似文献   

6.
VHS-ADC high speed digital signal processing platform based on MATLAB and FPGA could be used to build three-phase voltage source rectifier with space voltage vector PWM(SVPWM).The initial phase of coordinate transformation from three phase static coordinate to two phase static coordinate which is called Park transformation and from two phase rotating reference frame to two phase static coordinate is uncertain. There existed noise in acquiring grid voltage and current. Digital phase-locked loop is added to follow the frequency and phase of grid voltage, FIR filter is added to process signal and reduce the interference. External voltage control loop, internal current control loop and the model of coordinate transformation are designed on the VHS-ADC platform. The small power experiment is conducted to verify the stability and feasibility of the control system. The experimental results show that the digital phase-locked loop and FIR digital filter can be applied to three-phase voltage source rectifier.  相似文献   

7.
A new data culling and labeling method is proposed to avoid misleading outcomes caused by multi-state samples during drift compensation process. This method culls data by the curve slops of gas sensor array response and labels data by comparing input samples with the memories of pattern recognition algorithm to avoid occurrence of misleading results. Experiments show the method combined with on-line drift compensation algorithm can estimate sample-states automatically and increase the recognizing accuracy from 37.5% to 100%.  相似文献   

8.
Empirical mode decomposition (EMD) algorithm is introduded as the core of the Hilbert-huang transform (HHT), and implementation process of EMD is analyzed. Then data compression denoising algorithm based on EMD is proposed, simulation and experimental signals are used for verification of the effect of EMD. In the same data sources, the comparison of data compression denoising approaches based on the EMD, db2 wavelet and db8 wavelet are conducted. In addition, physical experiment of the same analysis and comparisons are conducted on a running motor in a Chongqing electrical plant. Simulation and experimental results show that data compression denoising algorithm based on EMD can achieve the same denoising effect, or even better than based on db2 wavelet, db8 wavelet. The former is more perfect than the latter in the real signal processing, and denoising based on EMD is not loss of the original signal energy.  相似文献   

9.
A method is proposed to determine the priority class of binary tree SVM. Firstly, the vibration signals of rotating machinery are colleted through a rotating machinery fault experimental platform and data acquisition system. The signals are from 5 different conditions, i.e. rotor normal, rotor unbalance, rotor misalignment, rotor bearing inner ring cracks and rotor bearing outer ring cracks. Then the signals are disposed by zero-mean and the main frequency band of the vibration signals are reconstructed to, extract the dimensionless time domain as characteristic value. Finally, the priority class of SVM 2PTMC can be determined by the correct inspection rate of parallel SVM. Training samples can be completely divided in experiments, which verifies the effectiveness of this method.  相似文献   

10.
A color image terminal which can be used for submarine acoustic imaging system is introduced in this paper. Imaging signals, data rate above 375 KB/S, can be in real time processed in this system. It can give an insert processing of the imaging signals produced in both Modes C and B. The coordinate can be transformed quickly and in real time when Mode Bworks The luminace information can be turned into false color information by a color coder. All kinds of imaging parameters are displayed on the screen at the same time. The raster scan system is used for the image terminal. The capacity of the image memory is 512k Bit. The characters, parameters and synchronous control signals are given by a microcomputer TP-805.  相似文献   

11.
The electrocardiogram (ECG) signal is a recording of the electrical activity on the body surface generated by the heart frequency of which is weak and low. Many researchers devote themselves to get more perfect ECG in many ways. This article introduces the characterize of an ECG signal , then discusses the requirements for the sampling circuit of an ECG. Since there are some shortcoming in common design means, the authors give an effective circuit. The system is composed of a low-cost , low-power and high-performance MCU C8051F020 , amplifier AD620 , right-leg drive circuit ,communication circuit and power management circuit. Then software design is given which is used to sampling and filtering ECG signal. Levkov filter arithmetic and smooth filter arithmetics are used in this design. In the end , the authors advance a distributing and networking ECG monitor system.  相似文献   

12.
针对在水泥路面裂缝图像识别中刻槽和纵向条带状形成的噪声干扰,提出了一种基于频域滤波的降噪增强方法。首先,分析了这两类噪声的频谱特征,并根据空域图像中刻槽的周期性,推导了频域图像中刻槽谱峰的位置,设计了消除这些谱峰的系列滤波器。根据纵向条带状干扰属于低频成分的特性,设计了抑制低频、增强高频的滤波器,经优化滤波器参数达到消除这类干扰的效果。实验结果表明,该方法能够消除两类噪声干扰,同时,增强了裂缝的对比度,为水泥路面裂缝识别提供了理论基础。  相似文献   

13.
By analyzing shortages of current MSPCA model, an on line multi variable statistical process monitoring method is proposed, which uses some concepts from online multi scale filtering and can be applied to sensor fault diagnosis. In the method, wavelet decomposition is employed to the signals using edge correction filter in a fixed length data window, and then wavelet denoising is conducted with wavelet threshold filtering. Next, an on line multi scale model is constructed for data combining wavelet transformation and adaptive PCA in the previous data window. This model avoids time waste in direct signal denoising and reduces time cost in multi scale data with conventional PCA, which eventually increases accuracy in fault diagnosis. Experiments on eight vibration signals of 6135D diesel engine under severe leak condition prove the practicability and feasibility of the proposed method.  相似文献   

14.
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   

15.
This paper firstly discusses some problem about the uncertain reasoning machine in the agricultural expert system based on HPC, such as the knowledge representation, the certainty factor, the representation of evidence uncertainty, the calculation of multi evidence uncertainty, the update of uncertainty and so on. Secondly, the control strategy of this uncertain reasoning machine is discussed. This control strategy adopts a converse reasoning strategy based on target, and it adopts a conflict removing strategy based on certainty factor. The arithmetic to realize the uncertain reasoning machine is also given in detail. At last, this paper stats the example of malnutrition diagnosing of grape as the application of the reasoning machine.  相似文献   

16.
The traditional scheduling for vehicle is option in the fixed network. But it can't satisfy the real time environment. The demand of order is changeable and uncertain in real environment. It is convenient for scheduling transforming it into static data, but can't get the advantage on time. This paper proposes a real time vehicle scheduling on the study of traditional scheduling and discusses the model structure and the key technology for the real time system that establishes the base for develop teal time system.  相似文献   

17.
One new auto-optimized fuzzy control model of car-engines based on genetic arithmetic was introduced aiming at the problem that the parameters of car-engine are of the discreteness, the nonlinear and the uncertain characteristics, with which it is difficult to control accurately the excess air coefficient and the spark advance angle in dynamic procedure when using a conventional control model. The rule of the design scheme of the controller achieving the model based on embedded operating system is discussed. Further more, it is probed that the fuzzy control parameters are optimized automatically using GA based on on-line real-time simulation. The results of experiments show that the dynamic indexes and the fuel economy indexes are all improved greatly and the advantage of the model on reducing fuel consumption is obvious.  相似文献   

18.
The high cost of grid connected photovoltaic (PV) system is an important reason that hinders its market application. The control cost can be partly cut down by using sensorless Maximum Power Point Tracking (MPPT). However, the sensorless MPPT control proposed by previous literatures has drawbacks of poor estimation accuracy, bad real time performance, and poor dynamic responses, which has great impact on the MPPT and the output performance of the whole system. Aiming at these problems, an Adaptive Sliding Mode Observer (ASMO) for estimation of photovoltaic array voltage is proposed. The external disturbance and modeling errors are suppressed while the real time performance and the estimation accuracy are improved greatly by the proposed method. The favorable performance of the output performance and MPPT performance of the PV system based on the ASMO are validated by simulation and experimental results.  相似文献   

19.
In practical industrial fields, it is very difficult to control uncertain complexity object effectively, because there are various uncertainties from internal dynamic characteristic and external, surroundings disturbance for controlled object. Its complexity is not only shown in structure, but also in information relation, so it is uneasy to implement it on technology. Aimed at selecting puzzle of control strategy for uncertain complexity system control, the authors describe cybernetics model based on analysis on some kinds of control strategy and contrastive research, and the model is applied in physical engineering system successfully. Finally, the authors point out that intelligent control strategy should be selected for uncertain complexity system control, and that Human Simulation Intelligent Control is a wise choice.  相似文献   

20.
The article analyzes two approaches of product visualization,and brings forward a common approach of product data to achieve Web visualization based on IGES standard. It transforms CAD data to universal and useful 3D data, it don't need special browser, and it is very simple and useful. A technological process is introduced to transform Web formats from IGES data. The article also describes concretely triangle anatomy of entity, and the minutia arithmetic of curve face. The principle that triangle piece realize to transform to VRML format is described. With the verification in the prototype system, this approach is proved with reason and credibility.  相似文献   

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