135 results about "Correlation spectrum" patented technology

The invention relates to a lasing fluorescence scanning imaging-fluorescence correlation spectrum unimolecule detecting instrument. Cover glass or a sample cell is arranged on an X-Y scanning platform; a microscope objective is installed on a Z-direction locator. Expended laser is filtered by an excitation filter, and then reflected into the objective by a dichroic mirror, and finally radiated in a sample above the cover glass after being focused by the objective; the sample generates fluorescence; and the generated fluorescence is collected by the same objective, passes through the dichroic mirror, and stray light is filtered off by an emission filter, and finally the filtered fluorescence is focused by a focusing lens on a small hole which is coupled with a single photon detector; and a signal generated by the single photon detector enters a computer through a data acquisition card. In the computer, three-dimension displacement and positioning system control software control the X-Y scanning platform to do X-Y two-dimension movement, and the Z-direction locator controls the focus of the objective to do Z-direction movement, thereby forming the three-dimension scanning to the sample; and three-dimension space position information and the signal generated by the single photon detector construct three-dimension scanning images and fluorescence correlation spectrum curves in the computer.

The invention discloses a method for extracting a Rayleigh surface wave frequency dispersion curve. The method comprises the following steps: a, performing Fourier transform on noise cross-correlation signals recorded by a seismometer pair which are spaced by R to obtain a frequency spectrum W(f); b, performing Gauss narrow-band filtering on the obtained frequency spectrum to obtain WG(f); c, extracting a real part curve of the WG(f), finding out null points of the real part curve, and recording fn as the frequency of the nth null point; d, finding out a root of a first-class zero Bessel function as Zn; e, solving a Rayleigh surface wave phase velocity value V(f) being equal to 2pifnR/Zn at a single frequency point according to the relation between a real part curve of a cross-correlation spectrum and the first-class zero Bessel function; f, connecting and drawing the solved phase velocities of single frequency points into a smooth curve as a frequency dispersion curve of Rayleigh surface waves. By using the relation between the Bessel function and the cross-correlation spectrum, the calculation efficiency of the frequency dispersion curve is effectively improved.

The invention relates to an intermediate infrared-near infrared correlation spectrum discriminating method for melamine-doped milk. The method comprises the following steps: (1) preparing pure milk for experiment and melamine-doped milk; (2) scanning intermediate infrared spectrums and near infrared spectrums of the pure milk for experiment and the melamine-doped milk; (3) calculating two-dimensional intermediate infrared-near infrared correlation synchronous spectrum matrixes of the pure milk for experiment and the melamine-doped milk respectively; (4) establishing a discriminating model by adopting a multi-dimensional partial least squares method; (5) scanning an unknown sample and calculating to obtain a two-dimensional intermediate infrared-near infrared correlation synchronous spectrum matrix of the unknown sample, and substituting the matrix into the discriminating model, thus judging whether the milk is doped with melamine. According to the invention, the capability of extracting feature information of dopant in milk through the two-dimensional intermediate infrared-near infrared correlation synchronous spectrums is fully utilized, the subjectivity of a direct comparison method for discriminating the doped sample based on the two-dimensional correlation spectrum is overcome, and the method is simple, easy and scientific, and is high in analyzing efficiency and discriminating accuracy.

A method for detecting near-infrared two-dimensional correlation spectra includes the following steps: a near-infrared spectroscopy detector is first set into an operating state, and after being prepared, a sample placed into a temperature-controlling accessory and positioned under a near-infrared detection probe; the temperature-controlling accessory is then utilized to control the temperature; afterwards, variable-temperature detection is carried out to obtain a series of spectrograms, and the spectrograms are digitalized; matlab software is run, and a calculation program is started to work out a dynamic spectrum; a band is selected according to a prompt to work out the synchronous diagrams and asynchronous diagrams of the two-dimensional correlation spectrum; and finally, according to the spectral characteristics in the synchronous diagrams and the asynchronous diagrams, identification or other qualitative analyses are carried out on the sample. The method spreads the absorption peaks of the spectrum on the second dimension, so that the spectral peaks of the near-infrared spectrum are more convenient to assign; by means of an analysis on the correlation between spectral lines, the interaction between different molecules or in molecules can be studied in detail; and by detecting the sequence of spectral intensity change, the process of chemical reaction and the kinetic process of molecular vibration can be effectively studied in detail.

The invention relates to a check problem for a linear frequency modulation/binary phase shift keying (LFM/BPSK) hybrid modulation signal blind-processing result, and provides a check method based on order statistic characteristics. A reference signal is constructed according to a signal model corresponding to a modulation identification result at first; then, a correlation spectrum of the reference signal and an observed signal is calculated; and thus, the LFM/BPSK signal blind-processing result is checked by detecting whether a peak value exists in the correlation spectrum or not. A computer simulation result shows that the method can perform effective check of the LFM/BPSK signal blind-processing result under a relatively low signal-to-noise ratio condition.

The invention relates to a measurement system for obtaining a single molecular spectrum and imaging under a shear field, characterized in that the measurement system includes: an excitation light source unit used as excitation light to irradiate a sample to be tested; a unit for applying a mechanical A shear application and rheological measurement unit for simultaneously measuring its macroscopic rheological properties; and an optical microscopic unit, the optical microscopic unit is used to introduce the excitation light emitted by the excitation light source unit into the waiting area under the shear field. The sample is measured, so that the dye molecules of the sample to be tested are excited to generate fluorescent signals, and the generated fluorescent signals are collected and respectively transmitted to a single-molecule fluorescence imaging unit, a single-molecule fluorescence emission spectrum measurement unit and/or a fluorescence correlation spectrum measurement unit . The invention can be widely applied to polyelectrolyte dilute solution, gel, interfacial diffusion, film imaging and other multi-charge condensed state systems, and explores the basic physical origin of its special properties.

Aiming at a blind processing result of an LFM (linear frequency modulation)/BPSK (Binary Phase Shift Keying) hybrid modulation signal, the invention proposes a verification method through GEV (generalized extreme value) distributed fitting verification. The method comprises the steps: constructing a reference signal at first according to a signal model corresponding to a modulation recognition result; calculating the square correlation spectrum of the reference signal and an observation signal, carrying out the appropriate segmenting, and then taking the maximum values of all segments to form grouped extreme value sequences; carrying out the GEV distributed fitting verification of the grouped extreme value sequences through employing an KS method, and carrying out the statistical judgment of the blind processing result of the LFM/BPSK signal. The simulation result of a computer indicates that the method can carry out the effective verification of the reliability of the blind processing result of the LFM/BPSK signal under the condition that there is short of signal and noise variance information.

A nuclear magnetic resonance transverse relaxation measurement method without J-coupling-effect interference is suitable for a routine liquid magnetic resonance spectrometer. The nuclear magnetic resonance transverse relaxation measurement method without J-coupling-effect interference can eliminate the J-coupling-effect interference. The method comprises the steps of (1), measuring a pi/2 nonselective RF pulse width required for exciting a sample; (2), introducing a nuclear magnetic resonance pulse sequence into the magnetic resonance spectrometer; (3), starting a transverse relaxation evolution module and a pure chemical shift decoupling module based on a perfect echo for the nuclear magnetic resonance pulse sequence, and setting experiment parameters of the transverse relaxation evolution module and the pure chemical shift decoupling module; (4), performing three-dimensional data sampling; and (5), after data sampling, performing related data after-processing operation, and obtaining a two-dimensional spectrum of which the direct dimension is the pure chemical shift information and the indirect dimension is the transverse relaxation time and error, namely a pure chemical shift-transverse relaxation time two-dimensional correlation spectrum.

The invention relates to an acquisition method of a surface enhanced Raman two-dimensional correlation spectrum. According to the method, a dynamic spectrogram of a sample to be tested is acquired through a Raman spectrometer, and the dynamic spectrogram is processed through spectrogram processing software to obtain the surface enhanced Raman two-dimensional correlation spectrum. The acquisition method of the surface enhanced Raman two-dimensional correlation spectrum is characterized in that the acquisition of the dynamic spectrogram includes the following two steps that first, the sample is prepared, and a site to be tested is marked; second, the laser intensity of the Raman spectrometer is set, the site to be tested is continuously irradiated to be infinitesimally disturbed by the laser of the Raman spectrometer at the laser intensity, a series of one-dimensional surface enhanced Raman spectrums of the site to be tested are acquired at the same time, and the dynamic spectrogram of the sample to be tested is obtained. According to the technical scheme, the site of the sample is continuously irradiated to be infinitesimally disturbed by the laser of the Raman spectrometer, operation is easy to perform and repeat, equipment is simple, and detection cost is low.

The invention discloses an analytic method for simultaneously determining the percentage content of nine impurity elements in titanium sponge. The nine impurity elements are Sn, As, Sb, Cr, Cu, V, Ni, Zn and Nb, five types of working curve standard solutions containing the nine impurity elements are prepared through a ti-based solution and a related reference solution, under the premise of determining the working parameters of the atomic emission spectrometer of an inductively coupled plasma, scanning is respectively performed on the five types of working curve standard solutions and a to-be-detected solution of titanium sponge, related spectral lines are selected as analysis spectral lines and background correction is performed on the analysis spectral lines, all related coefficients are higher than 0.995, detection limits are all below 0.00040 percent, except several analysis spectral lines of which the relative standard deviation is below 20 percent, the relative standard deviation of other analysis spectral lines are all below 10 percent, the requirements of a common micro trace analysis are met, the method provided by the invention can meet the requirements of analysis to the percentage content of the nine impurity elements in the titanium sponge, recovery tests show that the method is feasible, and a basis for quality grade of titanium sponge is provided.

The invention relates to a determination method in allusion to homogenous signal time difference under a multipath environment. The determination method comprises the following steps of: establishing a received signal sample, determining residual errors including self-correlation processing and determination of auto-regression parameters and finally determining time difference of two paths of signals through acquiring a cross-correlation spectrum of residual errors of two paths of signals. According to the invention, compared with the prior art that two paths of received homogenous sampled signals are directly cross-correlated, the determination method disclosed by the invention has the characteristics that residual errors of two paths of sampled signals are cross-correlated by an auto-regression method to ensure that related peak shapes are sharp and are still easy to distinguish even though arrival time difference of each signal is shorter, thereby effectively improving the time difference measurement resolution rate and accuracy; and the time difference value measured by the determination method accords with the theoretical value. Therefore, the determination method has the characteristics of being high in resolution ratio of the cross-correlation spectrum of sampled signals under the multipath environment, effectively improving the signal time difference determination accuracy, providing accurate parameters for subsequent positioning of a target signal source and the like.

The invention discloses a near-infrared autocorrelation spectrum detection method for melamine doped in milk powder. The method comprises the following steps: (1) preparing pure milk and milk powders doped by melamine with different concentrations; (2) scanning the near-infrared spectra of the pure milk and the milk powders doped by melamine; (3) carrying out calculation so as to obtain a synchronous two-dimensional near-infrared correlation spectrum matrix of the milk powders doped by melamine; (4) extracting elements on a principal diagonal of the synchronous two-dimensional near-infrared correlation spectrum matrix so as to obtain an autocorrelation spectrum matrix; (5) establishing a quantitative analysis model by using a partial least squares method; and (6) substituting the quantitative analysis model with the autocorrelation spectrum matrix of an unknown milk powder sample so as to obtain the content of melamine in the unknown milk powder sample. Compared with conventional one-dimensional near-infrared spectroscopy, the method provided by the invention can more effectively extract the characteristic information of trace melamine in milk powder, realizes accurate prediction of the content of melamine in the unknown milk powder sample, shortens modeling time, improves modeling and analysis efficiency and can be applied to adulteration detection of other food.

The invention discloses a tea/cosmetics quality detecting method based on two-dimensional correlation spectra. The method comprises the following steps: spectra acquisition comprising the steps of illuminating samples through LED, motivating visible near-infrared reflective spectra or fluorescence spectra of the samples and acquiring; spectrum preprocessing comprising the steps of preprocessing the acquired fluorescence spectra or reflective spectra; two-dimensional correlation spectrum obtaining comprising the steps of selecting feature regions from multiple different sample spectra, and carrying out synchronous correlation or asynchronous correlation calculation, to obtain synchronous spectra or asynchronous spectra; detection model establishment comprising the steps of establishing a sample two-dimensional correlation spectrum and sample level detection evaluation model based on a stoichiometry method; and sample quality detection comprising the steps of acquiring a dynamic spectrum of a new to-be-detected sample, calculating a two-dimensional correlation spectrum, bringing into the detection model, and analyzing to obtain a sample quality detection result. Based on the LED, the improvement on a quality detection system is relatively small, the cost is low, besides, rapid and effective high-precision detection can be satisfied, and the practicability is relatively high.

A credibility verification method for complex modulated signal processing results based on extreme likelihood ratio is disclosed, modified correlation spectrum used as the basis, a processing methodbased on NP-EVT criterion method of is proposed. Using EVT theory, the limit form of probability density function of normalized maximum statistic under different credibility assumptions is obtained. Based on NP criterion, the likelihood ratio test is constructed by this limit form, and a simplified likelihood ratio algorithm is proposed. The simulation results show the: the invention can effectively complete the credibility test of the LFM/BPSK composite signal blind processing result within a moderate signal-to-noise ratio range, without the prior information of the signal, is simple and effective, and has certain theoretical value and practical significance for improving the credibility and effectiveness of the radar and cognitive radio signal blind processing result.

The invention discloses a two-dimensional correlation spectroscopy multi-scale modeling method for olive oil impurity identification. The method comprises selecting the optimal two-dimensional wavelet basis, carrying out multi-scale decomposition and all layer respective reconstitution through the optimal two-dimensional wavelet basis, carrying out modeling and predicting on each layer of the reconstituted correlation spectrum through NPLS, acquiring a root-mean-square error subjected to cross validation, carrying out submodel fusion through the calculated weight, and evaluating multiscale-two dimensional correlation spectrum model result and performances through the predicted root-mean-square error and correlation coefficient. Compared with the routine model, the modeling method substantially improves a precision and reliability of a conventional Raman spectroscopy model, finds novel symptom information in a sample spectrum, prevents information loss, realizes simple and reliable Raman spectrum analysis and can be widely used in complex system spectral analysis.

The invention discloses a method for rapidly identifying red jujube varieties. The method comprises the following steps: respectively selecting hyperspectral data in upper, lower, left, right and middle areas of interest from each red jujube, and solving the average spectrum of the five areas of interest to serve as spectral data of the sample; measuring the maximum size of the length, width and height of the red jujubes through an MYD64A1 measurement light curtain so as to obtain an approximate volume of the red jujubes; selecting an optimal two-dimensional wavelet to perform multiscale decomposition on two-dimensional correlation spectroscopy and respectively reconstructing each layer; performing modeling prediction on each layer of reconstructed correlation spectrum and obtaining a root-mean-square error of cross validation; performing sub-model fusion through the calculated weight; and evaluating the result and performance of the multiscale-two-dimensional correlation spectrum model by predicting the root-mean-square error and correlation coefficient. According to the method disclosed by the invention, the maximum size of the length, width and height of the red jujubes is measured based on the light curtain method, and the red jujube varieties are rapidly identified by utilizing the volume difference and spectral data.

The invention belongs to the positioning or presence detection technology field utilizing radio wave reflection or re-radiation and discloses a radar signal modulation mode analysis method based on the improved HHT and a signal processing system. The radar signal time-frequency analysis method integrated with wavelet packet decomposition, CEEMD and correlation spectrum filtering is utilized to obtain each eigenmode component, improved Hilbert transform is utilized to obtain Hilbert spectrum instantaneous frequency distribution of a radar signal, and time-frequency parameter extraction of the radar signal is carried out. The method is advantaged in that a frequency component of an original signal is accurately extracted through utilizing the wavelet packet decomposition method for de-noising in combination with envelope correlation spectrum screening, problems of false components and modal aliasing caused by the noise are suppressed, a problem of the inaccurate HHT analysis result due to modal aliasing and the false components is effectively overcome, time-frequency distribution that is more aggregated and adapts to a lower signal-to-noise ratio is obtained through improved Hilberttransform, and high accuracy is realized.

The invention discloses a donor-acceptor distance distribution measuring method based on fluorescence correlation spectroscopy. Fluorescent labeled living cells of donors and acceptors are subjected to a selective donor excitation operation through a fluorescence correlation spectroscopy module of a laser scanning confocal microscope in different laser power. A correlation card acquires photon number fluctuation signals of a donor channel and an acceptor channel to form a self-correlation curve. Energy transfer rate and energy transfer efficiency can be calculated through triplet state analysis of the self-correlation curve of the acceptors. In addition, triplet state distribution of the energy transfer rate and the energy transfer efficiency can be inverted from the self-correlation curve of the triplet state of the acceptors through a maximum entropy algorithm so that donor-to-acceptor distance distribution can be calculated. A fluorescence correlation spectrum analysis method itself is an excellent technology of measuring concentration of a dilute solution, so that the measuring method can be used for measuring donor-acceptor non-paired fluorescence resonance energy transfer efficiency and donor-acceptor non-paired distance distribution after integration items of overlap items of the spectrum being corrected with respect to the donor-acceptor concentration proportion. The measuring method is convenient to use and high in measuring precision.

The invention discloses a method for detecting the polysaccharide content of ganoderma extracts based on spectra. Master-slave instrument spectra of samples of the ganoderma extracts are collected, spectra pretreatment of multiplicative scatter correction, Savitzky-Golay smoothing convolution and MSC+S-G is performed in sequence, and a two-dimensional correlation spectrum is generated; then multiscale decomposition is performed on the two-dimensional correlation spectrum by adopting an optimal two-dimensional wavelet basis, and all layers are respectively reconstructed; then the reconstructed spectrum of each layer is corrected by applying piecewise direct standardization, subsequently, prediction models which is based on partial least squares and is subjected to cross validation by a leave-one-out method are established, and finally, all of the prediction models are fused and evaluated according to calculated weight. The method has the advantages of fineness, precision and high efficiency, can be directly applied to the online detection of the polysaccharide content of the ganoderma extracts and has wide application and development prospects.

The invention discloses an in-water polycyclic aromatic hydrocarbon detection method based on two-dimensional fluorescence correlation spectroscopy.The method includes: (1) preparing mixed experimental polycyclic aromatic hydrocarbon aqueous solutions of different concentrations; (2) scanning fluorescence spectrums of each mixed experimental polycyclic aromatic hydrocarbon aqueous solution under different excitation wavelengths to obtain one-dimensional dynamic fluorescence spectrums; (3) adopting data of the obtained one-dimensional dynamic fluorescence spectrums to form a spectrum matrix, and carrying out two-dimensional correlation calculation to obtain a synchronous two-dimensional fluorescence correlation spectrum matrix; (4) establishing a quantitative analysis model according to the synchronous two-dimensional fluorescence correlation spectrum matrix and a concentration variable matrix of anthracene, phenanthrene and pyrene in each mixed polycyclic aromatic hydrocarbon aqueous solution; (5) substituting a synchronous two-dimensional fluorescence correlation spectrum of an unknown sample aqueous solution into the quantitative analysis model established at the step (4) to obtain concentrations of anthracene, phenanthrene and pyrene in the unknown sample aqueous solution.The in-water polycyclic aromatic hydrocarbon detection method based on two-dimensional fluorescence correlation spectroscopy has the advantages that feature information of polycyclic aromatic hydrocarbon pollutants can be extracted more effectively, quantitative analysis of in-water polycyclic aromatic hydrocarbon is realized, and easiness in operation and high analysis efficiency and analysis precision are achieved.

The invention relates to a device and a method thereof for acquiring a transmission fluctuation spatial correlation spectrum. A polychromatic light source is used for irradiation, when the light source passes through a dispersor, the distances between an incident light focus and reflected light focuses with different wavelengths in a measurement region are different, and thus the corresponding spatial correlations are different. An incident light beam and a reflected light beam are dispersed and absorbed in the measurement region under the action of particles, thereby causing extinction. A split light beam passes through a half reflecting and half transparent plain glass and is focused on a light sensing element by a lens, thereby obtaining a transmission correlation spectrum. The invention effectively solves the problem that the particle measurement range is limited because of mechanical operation in the measurement process. A transmission fluctuation spatial correlation spectral method is irrelevant to the flow field of the particles, has simple structure and can be used for detecting a particle system in laminar flow and onflow states in real time and on line, thereby testing the particle size distribution and the concentration of micron-sized particles. The invention can be widely applied to various fields of scientific research, production and process control of chemical industry energy sources, environment protection, water quality detection and particle measurement.

An embodiment of the invention discloses a noise detection method and device. The method comprises the steps as follows: a to-be-processed audio signal is obtained, and a power spectrum (omega) of an audio frame in the audio signal is computed; omega is the frequency of 2pi*power spectrum; autocorrelation Corr(tau) is computed according to the power spectrum of the audio frame, and tau is a time value; an enhanced correlation spectrum Ecorr (tau) is computed on the basis of the autocorrelation Corr(tau); the maximum value Max (ECorr) in Ecorr (tau) is obtained, and the audio frame is determined as noise if Max (ECorr) of the continuous predetermined number of audio frames is smaller than a first threshold; or, tau corresponding to Max (ECorr) is obtained, and the audio frame is determined as noise if tau corresponding to Max (ECorr) is not in the preset threshold range. Noise is identified on the basis of the enhanced correlation spectrum Ecorr (tau) and can be separated from music and human sound, so that a basis is provided for denoising.

The invention discloses a clary sage oil stability evaluating method based on a two-dimensional correlation spectrum. According to the clary sage oil stability evaluating method, on the basis of the thermal disturbance two-dimensional correlation Raman spectrum, corresponding dynamic spectra of a sample in a thermal perturbation action state are recorded for correlation analysis, and thus two-dimensional wavelet transformation is introduced to conduct high-dimensional multi-scale decomposition and hierarchical reconstruction on the correlation spectra; submodels of each layer of reconstructedcorrelation spectrum are conducted through parallel factor analysis; and finally, all the submodels are fused into a unique unified decision-making model through a method of weighting so as to finallyrealize judgment of quality stability of clary sage oil. Compared with conventional Raman spectrum analysis, through the clary sage oil stability evaluating method, the resolution accuracy and sensitivity of a conventional Raman spectrum analysis model can be significantly improved, thus a rapid evaluation method for stability of tobacco essence raw materials is constructed, stability quality control over the tobacco essence raw materials can be achieved step by step, and the quality control over the tobacco essence raw materials is greatly promoted.

The invention discloses a doped meat paste qualitative and quantitative detection method based on two-dimensional correlation infrared spectroscopy. The method comprises the following steps: preparing multiple pure meat paste samples and a mixed meat paste sample of multiple doping-level meats, and acquiring mid-infrared spectra of all the samples; calculating dynamic spectrum of the mid-infrared spectra and synchronous and asynchronous two-dimensional correlation spectrum; calculating Euclidean distance between two-dimensional correlation spectra of all the pure meat paste samples to be labeled as intra-group distance; calculating Euclidean distance between two-dimensional correlation spectra of the pure meat paste samples with known doping level to be labeled as inter-group distance; detecting significance of difference between the intra-group distance and the inter-group distance, and keeping sample data with significant difference; selecting a sample to be measured, and calculating Euclidean distance between two-dimensional correlation spectra of the sample to be measured and the pure meat paste samples to be labeled as unknown distance; and observing significance level of difference between the unknown distance and the intra-group distance and all inter-group distance and judging whether the sample to be measured is doping and its doping level.

The invention provides a textile classification and identification method based on an infrared spectrum detection technology. The textile classification and identification method comprises the following steps: S1, firstly, carrying out moisture absorption on dried samples of different types of textiles; for the same sample, preparing sub-samples with different water contents according to differentmoisture absorption time; s2, collecting near infrared spectrums of all the sample sub-samples; s3, performing two-dimensional correlation spectrum analysis on a series of sub-sample near-infrared spectra of each sample to obtain a synchronous two-dimensional correlation spectrogram and an asynchronous two-dimensional correlation spectrogram, and then fusing the synchronous two-dimensional correlation spectrogram and the asynchronous two-dimensional correlation spectrogram to obtain a mixed two-dimensional correlation spectrogram; and S4, establishing an image classification model by using aGoogLeNet image recognition model based on a deep artificial neural network in combination with a transfer learning method according to the spectral images of the different types of samples in the step S3, thereby realizing classification and recognition of the different types of textile samples. The method can effectively identify and classify different types of textiles with complex components and highly similar compositions.

The present invention relates to a vegetable oil identification and classification method based on two-dimensional correlation spectrum quantification. The method comprises the following steps: preparing a batch of samples; obtaining dynamic spectrum; performing spectrum preprocessing and band selection; performing two-dimensional correlation spectrum calculation and autocorrelation spectrum extraction; performing autocorrelation spectrum principal component analysis; and performing matching clustering based on the Euclidean distance. According to the method provided by the present invention,for the vegetable oil samples of unknown varieties, the first 8 principal components are used to match with each cluster center based on the Euclidean distance to determine whether the variety belongsto an established variety, so that identification and classification can be achieved.