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Evaluating ultrasound signals of carbon steel fatigue testing using signal analysis approaches

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Journal of Central South University 2014年第1期21卷 232-241页

作者： M.M.Padzi S.Abdullah M.Z.Nuawi S.M.Beden Z.M.Nopiah Department of Mechanical and Materials Engineering Universiti Kebangsaan Malaysia

The application of ultrasound techniques to monitor the condition of structures is becoming more prominent because these techniques can detect the early symptoms of defects such as cracks and other *** early detection of defects is of vital importance to avoid major failures with catastrophic *** assessment of an ultrasound technique was used to investigate fatigue damage *** tests were performed according to the ASTM E466-96 standard with the attachment of an ultrasound sensor to the test *** 1045 carbon steel was used due to its wide application in the automotive industry.A fatigue test was performed under constant loading stress at a sampling frequency of 8 *** sets of data acquisition systems were used to collect the fatigue strain signals and ultrasound *** of the signals were edited and analysed using a signal processing *** methods were used to evaluate the signals,the integrated Kurtosis-based algorithm for z-filter technique(I-kaz) and the short-time Fourier transform(STFT).The fatigue damage behaviour was observed from the initial stage until the last stage of the fatigue *** results of the I-kaz coefficient and the STFT spectrum were used to explain and describe the behaviour of the fatigue damage.I-kaz coefficients were ranged from 60 to 61 for strain signals and ranged from 5 to 76 for ultrasound signals.I-kaz values tend to be high at failure point due to high amplitude of respective *** spectrogram displays the colour intensity which represents the damage severity of the strain signals.I-kaz technique is found very useful and capable in assessing both stationary and non-stationary signals while STFT technique is suitable only for non-stationary signals by displaying its spectrogram.

关键词： fatigue ultrasound signal analysis integrated Kurtosis-based algorithm for z-filter technique short-time Fouriertransform

Simple Timing signal analysis Device-XY Mode Displays the Multichannel Shift Waveform

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Simple Timing Signal Analysis Device-XY Mode Displays the Mu...

Fingerprint enhancement algorithm based on signal analysis and reconstruction

作者： Dan GUI Dan ZHENG School of Electronic Engineering Wuhan Vocational College of Software and Engineering Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology MoE Key Laboratory for Biomedical Photonics Collaborative Innovation Center for Biomedical Engineering School of Engineering Sciences Huazhong University of Science and Technology Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Faculty of Physics & Electronic Science Hubei University

We designed and implemented a simple timing signal analysis device, which displayed multichannel shift waveform without overlapping from left to right on the Oscilloscope screen using X-Y mode as signal input. In order to meet the requirements of high speed sampling rate, we took microcontroller STM32F407VGT6 to collect, storage, analysis signal, and calculate the result wave though high speed DA conversion module to display on the Oscilloscope screen. we took microcontroller STM32F103RB to realize the shift clock circuit and 8-channel digital signal, and adopt the dial-code switch presents the 8-bit trigger word TW. after several test, the signal analysis device could realize the trigger time position adjust at all, time marker line be shifted manually, LED light displayed the status word corresponding to the flag line, and playback two shift cycle timing waveform and other functions simply and efficient. through numerical simulation and experimental analysis, we found that this simple device can greatly display multichannel shift waveform easily and precisely.

关键词： signal analysis X-Y mode Shift waveform Oscilloscope Display

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Fingerprint enhancement algorithm based on signal analysis a...

Accurate expression of neck motion signal by piezoelectric sensor data analysis

第43届中国控制会议

作者： Fengying Ma Ruzhou Tian Peng Ji School of Information and Automation Engineering Qilu University of Technology (Shandong Academy of Sciences)

The continuous advancement of biometric technology has positioned research on fingerprint recognition at the forefront,given the significant impact of fingerprint image quality on recognition *** enhance these images,signal analysis and reconstruction techniques are employed in this ***,the low-quality fingerprint image is analogized to an interference fringe image,and a corresponding mathematical model(LFMM) is ***,wavelet denoising is applied to the fingerprint image,while a Gaussian low-pass filter is utilized for grayscale compensation,eliminating terms related to grayscale compensation in the ***,the Ritz transform serves as an analytical function for signal analysis and reconstruction of the model,generating the fingerprint image's phase map(LFPM).Finally,Gabor filter enhancement is applied to the original fingerprint image using the fingerprint's phase map,completing the enhancement *** results demonstrate the effectiveness of the proposed enhancement algorithm in noise reduction and texture feature recognition enhancement,thus enhancing the accuracy and reliability of the fingerprint identification *** research carries significant implications for various domains such as security,forensics,border control,and personal identity verification.

关键词： Image enhancement signal analysis Ritz transform Fingerprint recognition

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Chinese Chemical Letters 2024年第9期35卷 250-256页

作者： Neng Shi Haonan Jia Jixiang Zhang Pengyu Lu Chenglong Cai Yixin Zhang Liqiang Zhang Nongyue He Weiran Zhu Yan Cai Zhangqi Feng Ting Wang State Key Laboratory of Digital Medical Engineering National Demonstration Center for Experimental Biomedical Engineering EducationSchool of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China SceneRay Co. Ltd.Suzhou 215123China School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China

The development of high-precision sensors using flexible piezoelectric materials has the advantages of high sensitivity,high stability,good durability,and *** main problem with sensing equipment is low sensitivity,which is due to the mismatch between materials and analysis methods,resulting in the inability to effectively eliminate *** address this issue,we developed the denoising analysis method to motion signals captured by a flexible piezoelectric sensor fabricated from poly(l-lactic acid)(PLLA)and polydimethylsiloxane(PDMS)*** results demonstrate that this improved denoising method effectively removes noise components from neck muscle motion signals,thus obtaining high-quality,low-noise motion signal *** decomposition and reconstruction is a signal processing technique that involves decomposing a signal into different scales and frequency components using wavelets and then selectively reconstructing the signal to emphasize specific features or eliminate *** study employed the sym8 wavelet basis for wavelet decomposition and *** the denoised signals,a high degree of stability and periodic peaks are distinctly manifested,while amplitude and frequency differences among different types of movements also become noticeably *** a result of this study,we are enabled to accurately analyze subtle variations in neck muscle motion signals,such as nodding,shaking the head,neck lateral flexion,and neck *** temporal and frequency domain analysis of denoised motion signals,differentiation among various motion states can be ***,this improved analytical approach holds broad application prospects across various types of piezoelectric sensors,such as healthcare monitoring,sports biomechanics.

关键词： Piezoelectric transducer Wavelet decomposition Muscle motion signal signal analysis Noise component Healthcare monitoring

Fiber Optic Gyro signal Random Drift Testing and Noise Error analysis

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Fiber Optic Gyro Signal Random Drift Testing and Noise Error...

A novel LAAS pseudo-range error over-bound method based on improved pseudo-range error distribution model

2010 3rd IEEE International Conference on Computer Science and Information Technology—ICCSIT 2010

作者： Bo Xu Huangqiu Zhu Wei Ji and Wei Pan The School of Electrical and Information Engineering JiangSu University Zhenjiang China

According to the bad influence of fiber optic gyro（FOG） signal random drift in inertia stabilized platform system, the properties of the FOG signal random drift are detected with the Allan variance method. By the relation between the Allan variance of signal noise and power spectrum density （PSD）, the sources of some kinds of noise and its properties are analyzed and calculated using fitting algorithm in the least square method （LSM）. The result of testing and statistic analyzing for FOG signal indicate that the Allan variance means is successful in separating and estimating the main random error source of FOG signal noise.

关键词： Fiber optic gyro Allan variance Power spectrum density signal analysis

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Chinese Journal of Aeronautics 2013年第3期26卷 638-645页

作者： Xue Rui Wang Zulin School of Electronics and Information Engineering Beihang University

The high level of safety demand of civil aviation requests local area augmentation system （LAAS） extremely high navigation integrity performance. A new LAAS pseudo-range error overbound method is proposed in this paper to improve the integrity of LAAS. Firstly, a more practical pseudo-range error distribution model is established. Then, by calculating the relationship between the statistical uncertainty of the model parameter and the integrity risk, a new method is proposed to calculate the pseudo-range error over-bound model. This method can effectively reduce the inflation factor and the resulting conservativeness of the over-bound model. Comparative experiments show that the method proposed in this paper performs better and satisfies the requirements of real applications.

关键词： Augmentation system Error statistics Probability density function Parameter estimation Satellite navigation signal analysis Uncertainty analysis

Gas Line Pressure Fluctuation analysis of a Gas-Liquid Reactor

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Journal of Thermal Science 2005年第3期14卷 267-271页

作者： J.J.J. CHEN J.C. ZHAO Chemical & Materials Engineering Department The University of Auckland Private Bag 92019 Auckland New Zealand ProfessorChemical & Materials Engineering Department The University of Auckland Private Bag 92019 Auckland New Zealand

To ensure efficient operation of metallurgical gas-liquid reactors, the gas bubbles must be uniformly distributed. For high temperature metallurgical reactors, it is impractical and unsafe to carry out visual observations. An air-water model was used to study the relationship between the bubble flow patterns and the pressure fluctuation signals. The fluctuation signals captured in the time domain were transformed into the frequency domain. Various parameters obtained from the transformed data were analysed for their suitability for delineating the bubble flow patterns observed. These parameters and the flow patterns were found to be well-correlated using the gas flow number.

关键词： gas liquid reactors bubble distribution signal analysis

A Mobile Cloud-Based eHealth Scheme

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Computers, Materials & Continua 2020年第4期63卷 31-39页

作者： Yihe Liu Aaqif Afzaal Abbasi Atefeh Aghaei Almas Abbasi Amir Mosavi Shahaboddin Shamshirband Mohammed A.A.Al-qaness Data Recovery Key Laboratory of Sichuan Province College of Computer Science and AINeijiang Normal UniversityNeijiang641100China Department of Software Engineering Foundation UniversityIslamabad44000Pakistan Department of Communication Faculty of Social SciencesUniversity of TehranTehran***Iran Department of Computer Science International Islamic UniversityIslamabad46000Pakistan Institute of Research and Development Duy Tan UniversityDa Nang550000Vietnam Kalman Kando Faculty of Electrical Engineering Obuda UniversityBudapest1034Hungary School of the Built Environment Oxford Brookes UniversityOxfordOX30BPUK Department for Management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Information Technology Ton Duc Thang UniversityHo Chi Minh CityVietnam School of Computer Science Wuhan UniversityWuhan430072China

Mobile cloud computing is an emerging field that is gaining popularity across borders at a rapid ***,the field of health informatics is also considered as an extremely important *** work observes the collaboration between these two fields to solve the traditional problem of extracting Electrocardiogram signals from trace reports and then performing *** developed system has two front ends,the first dedicated for the user to perform the photographing of the trace *** the photographing is complete,mobile computing is used to extract the *** the signal is extracted,it is uploaded into the server and further analysis is performed on the signal in the *** this is done,the second interface,intended for the use of the physician,can download and view the trace from the *** data is securely held using a password-based authentication *** system presented here is one of the first attempts at delivering the total solution,and after further upgrades,it will be possible to deploy the system in a commercial setting.

关键词： Cloud computing electrocardiograms health-care signal analysis signal processing

Novel method for detection of anomalous structure characteristics of ID precision ultrathin monocrystalline silicon section cutting tool

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Journal of Zhejiang University Science 2002年第3期3卷 263-267页

作者：陈宗农郭明王庆九余学功 DepartmentofMechanicalEngineering ZhejiangUniversityHangzhou310027China NationalHigh-PurltySilicon&SilicaneKeyLab ZhejiangUniversityHangzhou310027China

The structure characteristics of ID precision ultrathin monocrystalline silicon section cutting machine tool spindle with force monitoring bearings functioning as force measuring sensors were detected with the new Hilbert theory based signal wave envelope detection method, presented to replace the conventional hardware device in order to ensure that the signal is measured online with high fidelity. According to the probability of anomalous incidents in the cutting process, a mathematical recognition model has been designed and verified on an STC 22ID machine.

关键词： Machine tool spindle Bearing Monocrystalline silicon section signal analysis