I used inty,1,2 and found the area under the curve to be 2. The inversion procedure follows the determination of the dispersion curve e. It can only be plotted on a periodic structure, 1d, 2d or 3d. Here we present an opensource matlab package, named swpd surface.
For more information about fitting curves in the curve fitting app, see interactive curve and surface fitting. Another term for these statistics is measures of spread. Matlab 3d plot on dispersion curve matlab answers matlab. But avoid asking for help, clarification, or responding to other answers. Simultaneous measurement and inversion of surface wave dispersion and attenuation curves article in soil dynamics and earthquake engineering 229. Miller, and jianghai xia kansas geological survey, lawrence, kansas randy overton, elm consulting llc, olathe, kansas abstract accurate extraction of dispersion curves is the most critical part with any surfacewave method. Haney and leming qu, boise state university summary we compare inversions of rayleigh wave dispersion curves for shear wave velocity depth proles based on the l2norm occams inversion and l1norm tv regularization. Dec 10, 2015 nice greeting i am tring to write a matlab code for calculate the dispersion curve for surface wave, could any one assist me please.
The theoretical dispersion curves are developed based on newtonian mechanics for layer medium and has been programmed using matlab. Smooth response data matlab smooth mathworks nordic. The inverted swave velocities from the dispersion curve obtained at the optimal offset distance range also agreed with those obtained by using direct refraction survey. The dispersion curves obtained through forward calculation of the inversed layer parameters are basically identical to the actual dispersion cures in the form, only deviating in the local part. Computing a theoretical dispersion curve geopsywiki. A computer code for forward calculation and inversion of. Inspection and revision of the rayleigh wave dispersion curves via a.
This zip file contains a sample shotgather data set and a script to calculate the dispersion image of the data. The input of the diseca program is the dispersion curve vf, and consequently the resulting waveform corresponds to a 1d medium. Masw dispersion curve file exchange matlab central. Inversion of the experimental dispersion curves is generally an indispensable. Linearized multimodal inversion of multichannel surface waves for shallow profiles. In this paper an attempt has been made to develop the theoretical dispersion curve based on wave propagation in soils. Im using curve fit in matlab r2016a to find the best fit between two arrays. Inversion of vs, vpvs, and interface depth using multimode, rayleigh andor love, phase andor dispersion data and rayleigh wave fundamental mode zh data ellipticity based on the neighborhood algorithm in fortran. Surface wave analysis and its application to the calculation. Swave velocity profiling from refraction microtremor. Query tool for binary inversion report produced by dinverdc. First, particle swarm optimization code in matlab was developed.
Nice greeting i am tring to write a matlab code for calculate the dispersion curve for surface wave, could any one assist me please. I want to plot dispersion equation by matlab software, and this equation has complex function like bessel. It will be a 1d depth profile if only one dispersioncurve file. Sep 09, 2014 and i want to know the area under the curve generated in the graph, how would i do that. The material dispersion of fiber is evaluated from the given expression 15. Area under curve no function matlab answers matlab central. In hfss you need to simulate the design with appropriate boundaries in eigen mode solver. Pdf multichannel analysis of surface wave masw technique, which is based on.
Plots from dispersion curves and ground profile are merged in a single graphic sheet obviously, the dispersion curve is not perfectly fitted at high frequency due to the too simplistic parameterization used in this tutorial. Both the theoretical dispersion and attenuation curves are in satisfactory agreement with the. Overview this module generates a shearwave velocity vs profile 1d or 2d from input dispersion curve s. Thanks for contributing an answer to stack overflow. I only get pieces of them and a lot of points that.
The purpose of measures of dispersion is to find out how spread out the data values are on the number line. Modal separation before dispersion curve extraction by masw method julian ivanov, choon b. There is no function involved here, this is just raw data, so i know i cant use quad or any of those integral functions. As surface wave inversion is a typical example of nonlinear multiparameter problem. An example showing the dispersion function and the. You can approximate many curves with line segments, but a curve is a rather more general mathematical concept. Inversion of neural network rayleigh wave dispersion based. Determination of lamb wave dispersion curves by means of. Curve fitting toolbox allows you to smooth data using methods such as moving average, savitzkygolay filter and lowess models or by fitting a smoothing spline. Integration of a curve matlab answers matlab central. Plotting dispersion curves in matlab with contour hi everybody, has anybody ever plotted dispersion curves of plate waves using a contour line method.
Obsolete and replaced by gphistogram, it is kept only to process. Developed forward and inverse modelling of vertical. Old post processing tool for dispersion curves obtained from geopsyarray plugin tool. A matlab package for calculating partial derivatives of surface. The acoustic absorption within kwave is modelled using two phenomenological loss terms. Developed dispersion curves of layered medium using matlab matches well. Multimode inversion of multichannel analysis of surface. Can anyone help me with the matlab code for ebg dispersion. Haney and leming qu, boise state university summary we compare inversions of rayleigh wave dispersion curves for shear wave velocity depth proles based on the l2norm occams inversion and. The parameters used in this calculation can be found in table 1. These separately account for absorption that follows a frequency power law in addition to the associated dispersion dependence of the sound speed on frequency required by the kramerskronig relations. Diseca a matlab code for dispersive waveform calculations. These authors have used ga optimization techniques for inversion of surface wave dispersion curves.
The authors conclude that multimode dispersioncurve inversion needs to be paired with hrlrt for the correct identification and estimation of fundamental and highermode dispersioncurve data to arrive at accurate inversion results. I wrote a code for 2d plotting dispersion curves at specific frequency j1. Smoothing is a method of reducing the noise within a data set. Load the experimental dispersion curve from a text file e. If yes, you might be familar with the issues im facing see below trying this. If u is a uniform random number on 0,1, then x f 1 u generates a random number x from any continuous distribution with the specified cdf f. This script has been updated to include manual and automatic curve picking options. Could i use matlabsimulink to calculate the dispersion curve. We can either use the theoretical or the measured dispersion curve.
The dispersion curve corresponds to the layered medium, and is. A computer code for forward calculation and inversion of the. To improve inversion accuracy, i develop a method to simultaneously estimate the phase and group velocities of surface waves based on the generalized s transform. Appendix c synthetic model inversions with matlab code 7175. The waveguide dispersion is obtained from the expression. Simultaneous measurement and inversion of surface wave.
There is no function involved here, this is just raw data, so i. Masw shear wave velocity profiles are obtained based on raleigh wave dispersion curves. The script uses the phaseshift dispersion imaging scheme of park et al. The stationary point source gaussian dispersion model rio akasaka 09 engineering 66 the gaussian dispersion model serves as an excellent approximation to point source emission scenarios, such as coal plants with smokestacks. I have a sample of data passive array, that has been taken as a circular array of microtremors, and i want to get the love wave dispersion curve and invert it. One array represents a certain value at a given latitude and longitude and the other array represents the date that value was collected. Ps modeling dispersion curves 7 4 frequency range of the dispersion is specified. This work reports on methods for determination of lamb wave dispersion curves by means of fourier transform. It will be a 1d depth profile if only one dispersion curve file. How to plot a simple curve matlab answers matlab central. Use curve data scroll bar and visible button to identify it.
Theory lamb waves are twodimensional vibrations propagating in plates with free. Apr 10, 2018 this zip file contains a sample shotgather data set and a script to calculate the dispersion image of the data. Multimode inversion of multichannel analysis of surface waves. Rayleigh wave dispersion curve inversion via genetic. Comparison between dispersion curves of a perfect structure and dispersion curves of a defect structure is main feature of the guided wave method. Did you generate a collection of models that you want to use as the starting population for slightly different dispersion curve. This code has been combined with a variety of inversion methods to make up a powerful tool for passive seismic surveying. It can also export to ps, pdf and bitmap image formats. In recent years there has been increasing use of genetic algorithms in solving geophysical inverse problem e. The inversion method relies on the principle that continuous cumulative distribution functions cdfs range uniformly over the open interval 0,1. A matlab code is then employed for data processing showing how comsol can be very useful for the study of guided waves in plates and for comparison with the experimental data.
Generate random numbers using uniform distribution inversion. My question is that how i can plot those curves at different frequencies for example, j1. Shear wave velocity is estimated from the inversion of either phase or group. In using the curve fit tool im able to find a line of best fit as well as to plot the residuals. The agreement of the average dispersion curve for different components of the rayleigh wave and with the synthetic snsn dispersion curve demonstrates the robustness of the method and program.
Lamb waves and dispersion curves in plates and its. Curve fitting app creates a file in the editor containing matlab code to recreate all fits and plots in your interactive session. Dispersion analysis is an important part of inseam seismic data processing, and the calculation accuracy of the dispersion curve directly influences pickup errors of channel wave travel time. In order to evaluate the results for a real case we eventually considered a data set acquired on a waste fig.
To cope with noise and dispersion in the data, i introduce two cost functions. Multimodality of the surface wave dispersion curve inversion problem. This software allows users to obtain the theoretical solution for dispersion curve, tuning curve, frequency components for s0 and a0 wave modes, and the plate transfer function. Simulated annealing inversion of multimode rayleigh wave.
Dispersion analysis gui software for ambient noise crosscorrelation functions in matlab 4. Youll get a smoother curve in your plot if this value is small. The method is robust and it returns accurate results. Area under curve no function matlab answers matlab. A new framework was also proposed for the inversion of refraction microtremor rayleigh wave dispersion curves. Lamb waves as we said, lamb derived the dispersion relation for different waves traveling across the plane of a free plate. The table gives the function names and descriptions. This software allows users to obtain the theoretical solution for dispersion curve, tuning curve, frequency components for. Number of data points for calculating the smoothed value, specified as an integer or as a scalar value in the range 0,1 denoting a fraction of the total number of data points. Dc is imported, whereas a 2d depth and surface distance vs cross section will be produced if multiple files are imported. Results for a dispersion curve inversion with a 2layer model. The dispersion curve corresponds to the layered medium, and is independent of the source to receiver distance. I dont succeed in creating a clean plot of the curves. Overview this module generates a shearwave velocity vs profile 1d or 2d from input dispersion curves.
1133 567 439 633 730 1420 994 206 1097 274 1446 1290 572 1272 612 236 90 467 955 1057 432 510 241 837 1418 356 1372 29 1447 628 916 822 107