11 results about "Source spectrum" patented technology

The embodiment of the invention relates to the technical field of nuclear detection and measurement, and discloses a double-label nuclide analysis method and device and a program product, and the method comprises the steps: measuring a standard quenching source, and obtaining an external standard source spectrum index of the standard quenching source; drawing a correction curve by taking the external standard source spectrum index as an independent variable; measuring the double-labeled sample under external gamma source high voltage, and obtaining and calculating an external standard source spectrum index of the double-labeled sample through external gamma source spectrum stripping; determining the counting efficiency of low-energy nuclide, the counting efficiency of high-energy nuclide, the spectrum index of the low-energy nuclide sample and the spectrum index value of the high-energy nuclide sample corresponding to the double-labeled sample under the current quenching level according to the external standard source spectrum index of the double-labeled sample and the correction curve; the method comprises the following steps: measuring a double-labeled sample under double-labeled high pressure to obtain a full-spectrum counting rate and a full-spectrum sample spectrum index of the double-labeled sample; the low-energy nuclide activity and the high-energy nuclide activity of the double-labeled sample are calculated based on the parameters, so that the operability is higher, the accuracy is higher, and the application range is wider.

The invention provides an anti-noise interference frequency parameter estimation method for high-precision optical coherence ranging, which comprises the following steps: acquiring a spectral interference signal of an optical low-coherence interference system and a reference light spectral signal output only by a reference arm, and converting the spectral interference signal into interference signals with wave number space arranged at equal intervals, carrying out spectral density amplitude normalization to obtain a standard interference signal so as to eliminate interference of light source spectrum fluctuation and non-uniform sampling on frequency estimation; hanning window modulation is applied to a standard interference signal, spectrum leakage is suppressed, spectrum analysis is performed on the modulated signal, a peak value and an adjacent secondary peak value of a spectrum main lobe are extracted, a frequency correction amount is calculated based on a peak value and secondary peak value amplitude ratio relation derived by a Hanning window spectrum mode function, and an accurate frequency of the interference signal is obtained; and calculating the displacement of the object to be measured according to the product of the accurate frequency and the spectral resolution of the optical low-coherence interference system in combination with the refractive index of the light in the measurement medium.

The invention discloses a broadband FP (Fabry-Perot) cavity transmission spectral line calibration method and a calibration spectral line generation device, and belongs to the field of astronomical spectrum calibration. According to the invention, the laser frequency comb is utilized to carry out precise calibration on the FP cavity, the precision is an Hz magnitude, and the calibration precision of the radial velocity of the FP cavity can reach m / s; by tuning laser frequency comb parameters, all transmission peaks are supplemented, and broadband coverage is achieved; the high precision requirement for FP cavity coating is avoided, the accuracy of transmission spectral lines is ensured, frequent calibration is performed on the FP cavity, and the problem that the FP cavity cannot provide long-term stability of frequency is solved; a low-repetition-frequency picosecond white light source is used, the spectrum is wide and flat, the spectrum is not sensitive to the position of a transmission peak of an FP cavity, and the light enters a calibrated FP cavity array to generate a calibration spectral line with a high signal-to-noise ratio and multiple frequency intervals, so that the calibration precision of the astronomical spectrometer reaches the cm / s-level radial velocity calibration precision. The method is applied to the calibration of the astronomical spectrometer for extrasolar planet search.

The application discloses a kind of multi-parameter water quality synchronous detection and pollution source analysis traceability method and system, and relates to water quality monitoring technical field.The method includes: source signal screening is carried out to multimodal in-situ spectrum matrix source signal, and the candidate source signal of screening is analyzed, and pollution characteristic fingerprint spectrum is obtained;The pollution characteristic fingerprint spectrum is reconstructed on source spectrum matrix by constraint optimization, and the contribution weight of each potential pollution source to water sample pollution is quantitatively solved by minimizing reconstruction error;Based on the spatial index of node, the contribution weight of node is mapped to geographic information system, and the pollution characteristic component spatial distribution diagram is generated.The application directly solves the independent contribution weight of each potential pollution source from composite pollution spectrum by constraint optimization reconstruction, and can quantitatively separate different pollution source components in overlapping spectrum signal, to provide calculation basis for accurately locking pollution responsibility subject.

A method for improving the accuracy of SXR measurements, comprising: obtaining a first diffraction spectrum comprising a plurality of periodic discrete peaks and associated with a target structure that has been illuminated with a first source spectrum; obtaining a second diffraction spectrum associated with a target structure that has been illuminated with a second source spectrum, the second source spectrum being complementary to the first source spectrum; determining a first response spectrum of the target structure based on the first source spectrum and the first diffraction spectrum; determining a second response spectrum of the target structure based on the second source spectrum and the second diffraction spectrum; combining the first response spectrum with the second response spectrum to construct an improved response spectrum having fewer gaps than the first response spectrum; and determining a property of interest of the target structure using the improved response spectrum.

The invention relates to the technical field of GIS (Geographic Information System), in particular to an atmospheric pollutant transmission trajectory clustering analysis method and system, which comprises the following steps of: extracting sampling longitude and latitude time and toluene concentration, calculating a ratio to construct trajectory points, selecting core points to screen spatial neighborhoods, calculating a ratio difference and performing threshold filtering to form semantic neighborhoods; according to the method, the chemical fingerprints are constructed by extracting the concentration of methylbenzene and the concentration of benzene and calculating the ratio, concentration fluctuation interference caused by atmospheric dilution is avoided, double constraints are implemented by combining the spherical distance and the ratio difference value, interference points which are physically adjacent but have different components are removed, and the pollution source is determined. The method comprises the following steps: constructing a semantic connected set according to a difference sequence to generate a track cluster, reconstructing a homologous transmission path, calculating an in-cluster mean value, matching a source spectrum by using cosine similarity, quantifying component similarity to lock a pollution source, solving the problem of multi-source mixing by using an internal component rule, getting rid of meteorological parameter dependence, and improving traceability accuracy.

The invention relates to a wavelength selection method and system for passive spectrum calibration of an in-orbit ultraviolet spectrum instrument, and the method comprises the steps: building a standard line list of a preset wave band, carrying out the preprocessing, carrying out the single-line Gaussian fitting and local baseline modeling, carrying out the quality control through the asymmetry and wavelength deviation, calculating the quality weight of each middle standard line, and carrying out the calculation of the quality weight of each middle standard line. Calculating a similarity kernel of each standard line and other standard lines; based on the constraint of wavelength range endpoints, the constraint of the minimum distance between the two standard lines and the constraint of abnormal standard line elimination, screening the standard lines in the set of the standard lines after quality control by using a determinant point process; further screening according to the cross-day consistency and information amount combined evaluation standard line; and under a Bayesian framework, carrying out linear regression calibration on the standard line through a variable error model to obtain a finally selected standard line. The method is high in accuracy and high in stability.

The application provides a modeling-free mixture component intelligent identification method and system, which comprises collecting a plurality of mixture spectra of a to-be-tested sample, and pre-processing the plurality of mixture spectra; arranging the pre-processed plurality of mixture spectra into a matrix, and separating and outputting a plurality of source spectra; constructing a standard spectrum library, and correcting the standard spectra in the standard library and the separated spectra; detecting local extreme values of each source spectrum to obtain a peak position set; matching the peak position set with each pure component standard spectrum in the standard spectrum library, and judging an intersection number; if the intersection number is greater than a preset value, it is determined that the component exists, and an existing component list and a corresponding matching degree or similarity score are output. The application realizes modeling-free output of existence conclusion, solves the pain points of time-consuming verification of traditional methods depending on modeling, and realizes non-destructive, rapid and accurate qualitative verification of specific components in a textile mixture.

The present disclosure relates to a wavelength selection method and system for passive spectral calibration of an ultraviolet spectral instrument in orbit, the method comprising: establishing a standard line list of preset wavelength bands, and preprocessing, performing single-line Gaussian fitting and local baseline modeling, using asymmetry and wavelength deviation for quality control, calculating the quality weight of each standard line, and calculating the similarity kernel of each standard line and other standard lines; based on the constraints of the wavelength range endpoints, the minimum distance constraints of two standard lines, and the constraints of abnormal standard line rejection, the standard lines in the set of standard lines after quality control are screened by using the determinant point process; further screening according to the joint evaluation of cross-day consistency and information amount; under the Bayesian framework, the standard lines are linearly regressed by a variable error model to obtain the finally selected standard lines. The present disclosure has high accuracy and high stability.

The invention relates to the technical field of road sound insulation, and discloses a water chemical oxygen demand quantification model construction method based on multi-source spectrum fusion, which comprises a multi-source spectrum sensing layer and a multi-source fusion model, and specifically comprises the following steps: step 1, constructing a multi-source spectrum synchronous determination and effective fusion step; 2, constructing a dynamic interference compensation module; step 3, constructing a feature level fusion architecture; and 4, constructing a weighted decision fusion model. According to the invention, through the collaborative design of three optical paths, a coaxial light splitting probe is initiated, three types of spectrums are synchronously obtained through single sampling, and temperature / pH coupling correction coefficients alpha and beta are realized through a multi-stage fusion strategy, feature-level fusion (spectral feature extraction) + decision-level fusion (dynamic weight distribution) and drift real-time compensation, so that the spectrum drift error is reduced from 12% to 1.5%.

The invention relates to the technical field of spectrum models, and discloses a reservoir water body carbon sink strengthening system based on intelligent regulation and control, which comprises a multi-source spectrum sensing layer and a multi-source fusion model, and specifically comprises the following steps: step 1, constructing a multi-source spectrum synchronous measurement and effective fusion step; 2, constructing a dynamic interference compensation module; step 3, constructing a feature level fusion architecture; and 4, constructing a weighted decision fusion model. According to the invention, through the collaborative design of three optical paths, a coaxial light splitting probe is initiated, three types of spectrums are synchronously obtained through single sampling, and temperature / pH coupling correction coefficients alpha and beta are realized through a multi-stage fusion strategy, feature-level fusion (spectral feature extraction) + decision-level fusion (dynamic weight distribution) and drift real-time compensation, so that the spectrum drift error is reduced from 12% to 1.5%.