125 results about "Orthogonal decomposition" patented technology

A method and system is described for more optimally managing the usage of a wideband space-time multipath channel. The wideband space-time multipath channel is decomposed into a plurality of orthogonal sub-channels, where the orthogonal sub-channels having the best signaling characteristics are used for transmitting one or more signal streams. For purposes of decomposing the wideband space-time multipath channel into a plurality of orthogonal sub-channels, channel estimates are determined for each signal propagation path. A closed-form singular value decomposition of the channel corresponding to each receive antenna before coherent combining is utilized to obtain an orthogonal decomposition of the overall effective space-time channel after coherent combining. By using the overall effective space-time channel after coherent combining rather than before coherent combining, the complexity and correspondingly the resources required for obtaining the orthogonal sub-channels is significantly reduced. The method and system further provide for transmit power to be allocated between the selected sub-channels in order to minimize the effective bit-error rate for a fixed average throughput or to maximize average throughput for a fixed minimum effective bit-error rate.

The invention discloses a method for dynamically fusing, counting and forecasting air quality based on dynamic and thermal factors. The method comprises the following steps of: collecting data; introducing dynamic and thermal influence factors; performing empirical orthogonal decomposition of a vector matrix composed of influence factors having the significance level alpha, which is equal to 0.01, and selecting a principal component, the cumulative variance contribution of which is beyond 98%; establishing a regression equation by using the principal component; establishing a neural network model by utilizing a back-propagation neural network algorithm; performing evaluation check of a fitting result of the regression equation and the neural network model and the historical forecasting accuracy; calculating the final fusing and forecasting result by using a weighted average algorithm; performing evaluation check of the accuracy of the final fusing and forecasting result; and, adding new data into a historical data set in real time, and dynamically updating a forecasting model according to a check evaluation result. Compared with the existing method, the method disclosed by the invention has the advantages that: the relative error of various pollutant concentration forecasts is reduced by 3-11%; and the level forecasting accuracy rate is increased by 4-8%.

The invention provides a method and system for locating a three-dimensional space sound source. The method includes the steps that a microphone set comprising a plurality of microphones is arranged, the plurality of microphones are utilized respectively to record sound source signals to estimate the distance of the sound source; the microphones are combined in pairs, any two microphones are taken as a microphone pair, the angle of the sound source between the two microphones is calculated for each microphone pair, and the azimuth angle of the sound source between the two microphones is obtained; for each microphone pair, combined with the sound source distance obtained from estimation, the position of a virtual sound source in three-dimensional space is determined; an observation point is selected, orthogonal decomposition is carried out on virtual sound sources determined by all the microphones, horizontal angles and elevating angles of the sound sources are calculated, and the three-dimensional space position of the sound source is determined. By means of the method, the three-dimensional space position and size of the sound source are obtained in real time, and a reliable technical scheme of locating for sounding objects in non-visible areas in the field of security monitoring, robots and the like is provided.

The invention discloses a method for processing a broadband receiving digital front end, which comprises the following steps that: 1, received radio frequency signals are divided into n paths of signals, and each path of the signals is subjected to frequency mixing respectively, and the difference of the frequencies of the frequency mixing among the paths is 80 MHz, then the paths of signals are processed respectively and are transmitted to an AD (Analogue-Digital Converter) for sampling with the sampling frequency of F1, and digital medium frequency signals with the centre frequency of F2 and the bandwidth of 80MHz are generated by each path, and are transmitted to a FPGA (Field Programmable Gata Array) for processing; 2: a corresponding AD is selected to input signals according to a current signal frequency code of the system, a DDS (Digital Display Scope) is controlled to generate orthogonal digital local oscillation consistent with a signal frequency spectrum sampled by the AD, the signals input by the AD are multiplied by the orthogonal digital local oscillation generated by the DDS respectively and the frequency spectrum is shifted to a zero intermediate frequency to carry out orthogonal decomposition to acquire an I path of baseband signals and a Q path of baseband signals which are orthogonal to each other; and 3: the velocity of a signal data stream acquired after theshift of the frequency spectrum is F1, the signals are subjected to extraction filtering for M times by using a CIC extraction filter to acquire an I baseband signal and a Q baseband signal with the velocity of F1 / M, and the baseband signals are subjected to complementary filtering respectively by using an FIR low-pass filter.

The invention discloses a multimedia content protection and safe distribution method in a cloud environment. The method comprises steps of encrypting original data of a data owner DO; authorizing a data request of a data user DU; generating a watermark ciphertext; generating a re-encryption key; generating a watermark re-encryption ciphertext; and authorizing a user to decode the re-encryption ciphertext. Based on transition characteristics of the re-encrypted ciphertext, ciphertext data of the data owner is transformed into decodable ciphertext of the data owner and it is ensured that the transmission operator cannot obtain any information of the cleartext. According to the characteristics of orthogonal decomposition, the re-encryption algorithm is seamlessly combined with the digital watermark technology, so the method provided by the invention is formed. Computing and storing ability of the cloud computing can be well used and privacy and safe distribution of multimedia contents are ensured.

The invention relates to the technical field of printing technology path generation, and discloses a helix outline offset filling optimization method and a helix outline offset filling optimization system, wherein with the method, the system, the idle stroke and the number of the jumping of the scanning head during the printing can be effectively reduced, the filling precision and the perfect appearance can be ensured, and the printing speed and the system stability can be further improved. The helix outline offset filling optimization method comprises: obtaining the three-dimensional model ofa to-be-printed three-dimensional entity, and determining a filling interval d; carrying out slicing layering on the three-dimensional model, and extracting the apex coordinate information of the to-be-filled polygon outline after the slicing; obtaining the offset filling paths of each layer of the three-dimensional model in the plane by using the existing helix outline offset algorithm; calculating the coordinates of the connection apexes between the outlines by using orthogonal decomposition principle according to the apex coordinate information of the outline in the same layer so as to optimize the filling path; and replacing the original offset filling path with the optimized path, and updating the filling paths of each layer.

The invention discloses an ocean remote sensing image water color and water temperature monitoring method based on compression sampling. The monitoring method comprises the following steps of: obtaining original remote sensing data of ocean water color or water temperature to be detected, and carrying out compression sampling, sparse transformation and image processing on the original remote sensing data to obtain a water color or water temperature data set; sequentially conducting denoising and reconstruction processing on the water color or water temperature data set through an SOM (self-organized mapping) algorithm to obtain a processed water color or water temperature data set; conducting denoising processing on the processed water color or water temperature data set and reconstructing missing image data by utilizing the continuous interpolation property; and outputting and displaying the reconstructed missing image data. The monitoring method utilizes the compression sampling principle for reducing the amount of processed data, and utilizes the advantages of nonlinear estimation of the SOM algorithm as well as linear estimation and continuous interpolation of an improved empirical orthogonal decomposition (EOF) algorithm and the like so as to improve the efficiency of reconstructing missing images, expand the scope of the reconstructed images, and enable the precision and efficiency of ocean remote sensing water color and water temperature monitoring to be high.

The invention discloses a method used for identidying material anisotropic plasticity parameters based on spherical impression morphology. According to the method, a spherical impression equipment isadopted for indentation test of a test piece so as to obtain impression morphology response information left on test piece surface; orthogonal decomposition and parametric approximation are adopted soas to obtain a value model used for representing the relationship of the material anisotropic plasticity mechanical property parameters with the impression morphology response information, reverse derivation constraint optimization problem is adopted so as to obtain the anisotropic plasticity mechanical property parameters of the material to be test through reverse derivation. In applications, the spherical impression morphology information obtained in the indentation experiment is input into the value model, and the anisotropic plasticity mechanical property parameters of the material to betest are obtained through certain steps of calculation. The method can be used in anisotropic material small size sample detection, nondestructive test, and material in-suit test, and the accuracy ofmaterial anisotropic plasticity parameters obtained via reverse derivation using the method is high.

The invention relates to a plane component deformation decomposition and vibration mode identification method based on an orthogonal decomposition theory. The method comprises the following steps: step 1, the plane deformation of a four-node square unit is formed by laminating eight basic deformation such as the rigid body displacement in an x direction, the rigid body displacement in a y direction, the extruding deformation in the x direction, the extruding deformation in the y direction, the bending deformation in the x direction, the bending deformation in the y direction, the shear deformation and the rigid body rotation displacement; targeting for the four-node square unit, an orthogonal decomposition method is adopted to respectively establish the basic deformation vector of each of the rigid body displacement in the x direction, the rigid body displacement in the y direction, the extruding deformation in the x direction, the extruding deformation in the y direction, the bending deformation in the x direction, the bending deformation in the y direction, the shear deformation and the rigid body rotation displacement. The method is also applicable when the structure of a plane component is divided into large units, the calculation workload is alleviated; moreover, the bending deformation and the shear vibration mode can be identified, and the stress situation and vibration type inside a component can be more accurately and completely reflected.

The invention provides a multi-user dispatching method in an MIMO system and a device thereof. The method comprises the following steps that: each mobile station selects an optimized vector which is matched therewith in a preset codebook as a quantifying information channel, computes information channel quality information corresponding to the quantifying information channel, and reports the information to a base station; and the base station selects a first user to be dispatched from users to be dispatched according to a preset dispatching principle, obtains a precoding matrix from the quantifying information channel corresponding to the first user to be dispatched by means of orthogonal decomposition, and takes the users which are matched with the other column vectors except the first column vector in the precoding matrix as the other users to be dispatched. The scheme of the invention can effectively improve the performance of the MIMO system.

The invention relates to a Legendre-orthogonal-decomposition-baesd curve motion trajectory SAR wave-number domain imaging method. The method comprises: constructing a slant range history expression ina curved motion trajectory mode by using a three-dimensional speed and a three-dimensional acceleration; carrying out polynomial expansion on the constructed slant range history expression and carrying out keeping to the fourth order; transforming an SAR echo signal corresponding to the slant range into a two-dimensional frequency domain to obtain a two-dimensional frequency spectrum; with a Legendre orthogonal polynomial, spreading the two-dimensional frequency spectrum for a distance range frequency and carrying out keeping to a third order; carrying out phase compensation based on a two-dimensional frequency spectrum developed based on Legendre and completing distance migration correction and distance range focusing; and carrying out azimuth compression in a distance-Doppler domain andcarrying out transformation in a two-dimensional time domain to obtain a focusing image. Therefore, a target imaging blurring problem at the scene edge is solved.

The invention provides a wide band spectrum signal denoising method based on wavelet threshold difference. Wavelet decomposition is carried out on spectral signals with noise to obtain multilayer wavelet coefficients; soft threshold denoising is carried out on the multilayer wavelet coefficients to obtain the denoised multilayer wavelet coefficients; a Hankel matrix is constructed by wavelet coefficients of each layer after denoising; a singular value matrix is constructed according to the Hankel matrix, and singular values are obtained by orthogonal decomposition of the singular value matrix;difference calculation is carried out on the singular values to construct a singular value difference spectrum; singular value difference denoising treatment is carried out on the singular value difference spectrum; the denoised singular value matrix is calculated in a reconstructing mode to obtain the denoised Hankel matrix so as to reduce to denoised wavelet coefficients; and the denoised wavelet coefficients are subjected to inverse wavelets transform through a Mallat algorithm to obtain denoised spectral signals. The wide band spectrum signal denoising method has complete denoising effect, effective spectral characteristics can be retained, and measurement precision and accuracy of a wide-band spectrometer are improved.

This invention relates to a digital signal processing method for multi-channel high-frequency radar receiver. Sampling the MF signal by band-pass sample for orthogonal decomposition; obtaining the in-phase component I and orthogonal component Q by digital orthogonal transformation based on multi-phase filter for extract respectively; taking the I and Q in one group as the real and imaginary part of a complex signal respectively for complex FFT; multiplying a phase-shift factor e-j*w(k) to every FFT result for accumulation, and then obtaining the distance information. Instead of prior art, This invention saves almost complete echo information, reduces operation amount, and improves system efficiency.

The invention provides a photonic crystal fiber transverse stress sensor based on temperature compensation. Four super-large side holes in cross distribution are introduced in an optical fiber cladding layer; each side hole is internally coated with a gold nanofilm, and one side hole is filled with magnetic fluid; and small air holes are distributed in the cladding layer in an octagonal manner. The sensor realizes high-sensitivity transverse stress sensing in any direction. A measurement device thereof comprises a light source portion, a transverse stress sensor portion and a demodulation portion. The sensor combines the super-large side holes with surface plasma technology, thereby greatly improving the sensitivity of the transverse stress sensor. Magnetic fluid filling causes Y polarization fundamental mode loss peak to have double peaks, brings new degree of freedom and realizes temperature compensation. Through a multi-parameter demodulation and orthogonal decomposition method, measurement of transversal stress in any direction is realized. The result shows that, under the transversal stress, fundamental mode X polarization maximum sensitivity is 3.4 nm / N, and Y polarization maximum sensitivity is 4.6 nm / N. The sensor is simple in structure, high in sensitivity, small and compact, and is suitable for accurate measurement of transversal stress in multiple fields.

The invention belongs to the field of multimedia information security protection and particularly relates to a bag-of-word model-based image security retrieval method for a cloud environment. The method can be used for security retrieval of ciphertext images. A content owner extracts feature operation data of the images based on a bag-of-word model, performs orthogonal decomposition to obtain a password operation domain and a feature extraction operation domain, performs encryption operation and feature extraction operation, superposes operation results in a same data domain through orthogonal inverse transformation to form encrypted features, and uploads the encrypted features to a cloud server. When a user needs to retrieve the images, the cloud server can calculate out the features of the ciphertext images in the data domain of feature extraction by directly performing orthogonal decomposition on ciphertext features without performing decryption; the features of the ciphertext images and the features of the images requested to be retrieved are subjected to similarity measurement; and the images with the highest similarity degree are the to-be-retrieved images. The retrieval method does not depend on a specific encryption method, is high in security and has higher universality; and the bag-of-word model-based retrieval method has very high retrieval precision.

The invention provides a high-security orthogonal decomposition chaotic scrambling method based on position information. Both a sending end and a receiving end know the position information of a legal user; an initial value of a chaotic sequence for displacement is decided according to the position information of the legal user; and a selection mode of the initial value is random and discordant, so an eavesdropper is difficult to recover obtained interception information. According to the orthogonal chaotic scrambling scheme based on the position information provided by the invention, the sending end does not need to know the position information of the eavesdropper, cipher transmission does not need to be carried out through a special control channel, and a channel gain matrix of the eavesdropper does not need to be different from the channel gain matrix of the legal user. According to the method, the reliability, security and practicability of a visible light communication system can be improved.

The invention discloses a method for rapid simulation of a non-stationary random course based on characteristic orthogonal decomposition. With regard to a multi-point non-stationary course which has arbitrary space distribution and is related to time variation, an EPSD matrix is composed triangularly at first, then POD is used to denote each time-frequency coupled element of the triangular matrix by the sum of products of multiple time functions and multiple frequency functions, and finally an FFT technology is used for rapid simulation; and with regard to a multi-point non-stationary course which has arbitrary space distribution and is related with time invariability, a related matrix is decomposed triangularly at first, then POD is used to denote time-frequency coupled elements of a diagonal matrix composed of auto spectra by the sum of products of multiple time functions and multiple frequency functions and finally a simulation formula is optimized, so that the FFT technology is only used for a few of times for efficient simulation. According to the invention, the POD is used, fitting accuracy is high, and simulated samples are accurate; simulation efficiency is greatly increased through triangular decomposition and optimal use of the FFT technology; and problems existing in current non-stationary simulation methods that applications are limited and efficiency is low can be solved.

Disclosed is a method for real-time prediction of thermal-insights for a heat dissipating device in a data center cooled by one or more cooling units. The method uses a concept of influence mass fractions in conjunction with proper orthogonal decomposition (POD) based reduced order model. It may be understood that, the influence mass fractions may be computed by performing a fixed number of CFD simulations based on mass flow rates of the one or more cooling units. The method further facilitates to identify a set of reference scenarios for a given range of operational parameters of the one or more cooling units impacting the heat dissipating device. The set of reference scenarios may then be provided to the POD in order to predict the thermal-insights of the data center such as a temperature, mass flow rate, and insights into thermal influence of air sources on the heat dissipating device.

The invention discloses a method for analyzing a random response of a non-proportional damping structure under an earthquake effect. The method comprises the following specific steps: 1, acquiring a unit impulse response of the structure about any excitation; 2, based on a random vibration theory, establishing a direct convolution formula responding to power spectrum calculation; 3, performing PODfeature orthogonal decomposition on the non-uniform modulation function excited by each point; and 4, calculating an evolution frequency response matrix by using FFT, and further determining an evolution power spectrum matrix and a variance matrix of the structure response. According to the method, the response statistics is explicitly represented as the convolution form about the pulse response,and the convolution is calculated by using the FFT technology, so that the response calculation efficiency is greatly improved; the method is suitable for a linear structure, is also suitable for a nonlinear structure, and can also be used for a linear system subjected to order reduction through a modal superposition method.

The invention relates to a geomagnetic field disturbance real-time analysis forecasting system comprising a historical and real-time observation data device, a local geomagnetic field disturbance analyzing device and a geomagnetic field disturbance forecasting module, wherein the historical and real-time observation data device is used for monitoring the varying conditions of a geomagnetic field in real time; the local geomagnetic field disturbance analyzing device comprises a data preprocessing and storing device, a multiple regression analysis model device, a geomagnetic ambient field dynamic extracting device and a real-time geomagnetic field disturbance condition analyzing device; and the geomagnetic field disturbance forecasting module comprises a natural orthogonal decomposition feature vector model device, a feature vector set constructing device, a weighing single-step forecasting device, a geomagnetic field disturbance forecasting analyzing and storing device and a geomagnetic field disturbance forecasting output device, thereby providing the geomagnetic field disturbance real-time analysis forecasting system for forecasting the future geomagnetic field disturbance degree through observing data and analyzing the integral variation degree of the local geomagnetic field in real time by utilizing a single geomagnetic station.

The invention provides a method for X-band radar wave retrieval based on empirical orthogonal decomposition. The method includes constructing a covariance matrix by utilizing X-band radar echo data, conducting empirical orthogonal function decomposition on the covariance matrix, obtaining characteristic vector and characteristic root of main mode through determination, establishing a relation between the wave height He, the main modal characteristic root and the average signal to noise ratio SNR of radar echo, fitting by utilizing simulation or actual measurement data to obtain a relation coefficient, establishing a relation between the wave direction Di and phase of the main modal characteristic vector, fitting by utilizing simulation or actual measurement data to obtain a relation coefficient, and carrying out real-time wave parameter retrieval according to the established relation between the wave height and wave direction. The method is complementary to a conventional spectrum analysis retrieval algorithm, and improves the precision for X-band radar wave retrieval.

The invention relates to a wind power generator system, a wind energy data error correction method and a yaw control method. Firstly, orthogonal decomposition is carried out on initial wind speed vector detected by wind energy data detection equipment, the initial wind speed vector is divided into an initial wind speed axial vector and an initial wind speed tangential vector, and then the tangential speed vector of the wake flow at the wind energy data detection equipment is calculated according to parameters such as tangential induction factors of the wake flow of a draught fan; and then thecorrected wind speed tangential vector is calculated according to the initial wind speed tangential vector and the wake flow tangential speed vector, finally, the corrected wind speed tangential vector and the initial wind speed axial vector are combined to obtain the corrected wind speed vector. The corrected wind speed tangential vector has removed a draught fan wake flow factor, so that after the corrected wind speed tangential vector and the initial wind speed axial vector are combined, the combined wind speed and wind direction are basically consistent with the actual wind speed and winddirection in front of the draught fan, deviation between the detected wind energy data and real wind energy data is eliminated, the authenticity of the data is guaranteed, and follow-up yaw control isfacilitated.

The invention discloses a voltage and current vector relation based on residual current detection method which is especially used for simultaneously detecting residual voltage and residual current and utilizing the voltage and residual current vector relation to judge whether residual current is harmful or not, namely judge whether the residual current causes lethal influence on people or lethal. According to the voltage and current vector relation based on residual current detection method, orthogonal decomposition is conducted on a residual current vector according to voltage vector direction, it is shown that the residual current has harmful components when a product of a parallel component of the residual current vector and a voltage vector is not 0, and a corresponding protection indication is needed to be made when the sum of the harmful components of harmonic components of the residual current exceeds a limit value which can be borne by the people or the livestock. The voltage and current vector relation based on residual current detection method is accurate in metering and high in reliability, can be used in the relevant fields of residual current detection, monitoring, electric leakage protection devices and the like and has very wide prospect.

The invention discloses a method for preprocessing furnace temperature distribution data of a scrap copper smelting furnace. The method comprises the following steps of: acquiring a data set of furnace temperature distribution of the smelting furnace in a stable working state by applying the existing hydrodynamics analog simulating calculation; then selecting a characteristic data set from the data set, and acquiring a space-based function of characteristic changes of the furnace temperature distribution of the smelting furnace through an orthogonal decomposition method; acquiring estimated values of time parameters for furnace heat transfer of the smelting furnace by using a least square method according to space-time distribution characteristics of the furnace heat transfer of the smelting furnace; and finally, acquiring the furnace temperature distribution data of the smelting furnace, which consists of the estimated values of the time parameters and a linear function of the space-based function. By adopting the method, the memory capacity of the data is reduced and the memory space of a processor is released to ensure that the processor can run smoothly, so that the smelting process of scrap copper is accurately controlled.

The invention discloses an orthogonal decomposition based shear deformation testing method adopting laser displacement meters. One side surface of a zone, to be subjected to shear deformation, of a test piece is selected, an x-direction laser displacement meter 1 and a y-direction laser displacement meter 2 are arranged in the width direction and the height direction of the test piece respectively, a laser displacement meter transmitting plate 3 is also fixed on the side surface of the test piece, parallel to a neutral axis L and located at an orthogonal surveying and mapping point of the x-direction laser displacement meter 1 and the y-direction laser displacement meter 2; after tangential load is applied, and x-direction displacement variation Sx and y-direction displacement variation Sy in the zone are tested respectively on the basis of the laser displacement meters, so that the average shear strain in the zone is obtained. With adoption of the method, measurement precision of shear deformation of the test piece can be improved effectively, and data has high utilization ratio.

The invention relates to a fingerprint encryption template protection method and system based on orthogonal decomposition. In the process of registration, fingerprint acquisition, preprocessing and fingerprint feature extraction based on orthogonal decomposition are included, and dividing orthogonal codes in an orthogonal decomposition domain to obtain a fingerprint feature encryption operation domain and a feature matching operation domain independent of each other and then merging ciphertext features and matching features by orthogonal synthesis are included; a fingerprint encryption template is stored, and an orthogonally synthesized ciphertext template is stored into a library. In the process of authentication, after fingerprint acquisition and corresponding preprocessing operation are carried out, fingerprint feature extraction based on orthogonal decomposition is also carried out, feature matching is then carried out, and extracting fingerprint feature s in the feature matching operation domain by orthogonal decomposition and comparing with a feature matching domain of a stored template to carry out identity authentication. The invention can effectively protect fingerprint data privacy, has high security, and also has high safety and universality.

The invention relates to an analog signal self-adaptive demodulation system and its implementation method, comprising a front panel, a signal processing board, and a receiver. The chip and the crystal oscillator are connected to the FPGA in one direction, the ARM processor and the network port chip are connected to the interface MCU in two directions, the interface MCU is connected to the FPGA in two directions, the input filter is connected to the ADC in one direction, and the ADC is connected to the FPGA in two directions. The panel is bidirectionally connected to the interface MCU, the signal source is bidirectionally connected to the network port chip, and the receiver is unidirectionally connected to the input filter. The demodulation module performs orthogonal decomposition on the sampling signal, and the sine and cosine signals generated by the numerical control oscillator are respectively multiplied by the sampling signal to obtain I The quadrature signal of channel Q and channel Q are filtered out by low-pass filter to remove high-frequency components, and then extract and reduce the speed to demodulate the modulated signal, and the result is output through the standard interface to realize automatic identification of signal modulation style and carrier synchronization , bit synchronization, frame synchronization.

The invention discloses a mutual information forwarding relay transmission method based on unitary space-time modulation. The mutual information forwarding relay transmission method based on unitary space-time modulation comprises the following steps that in a parallel relay multi-antenna network with all nodes not knowing channel state information, a source node sends unitary space-time symbols to each relay node for communication; the relay nodes process received signals correspondingly, and the relay nodes forward soft signals combining hard decision signals and a mutual information value to a destination node and provide soft information for decoding of the destination node; based on a signal orthogonal decomposition principle, source signals in the signals received by the destination node are distinguished from non-correlated noise signals, and the power ratio of the source signals and the non-correlated noise signals is the general signal-to-noise ratio of the destination node. The relay nodes forward the soft signals combining the hard decision signals and the mutual information value, and provide the soft information for decoding of the destination node, and the reliability of the system is improved.

The invention relates to a theoretical detection method for determining the location of a damaged fastener. The theoretical detection method includes the steps that (1) a sensitive index limiting value is calculated, specifically, a modal superposition method is adopted, ordinary differential vibration equations of a steel rail and lining can be respectively obtained through orthogonal decomposition, the ordinary differential vibration equations are combined with a train body formula, single fastener damage is introduced, the fastener rigidity is 0 at the damaged fastener location x0, and vertical acceleration of a car body when a first wheel of the car body passes above the damaged location is the sensitive index limiting value and obtained; and (2) the damaged location is distinguished. The theoretical detection method has the beneficial effects that a subway integrated track bed train track coupling model is established, an integrated track bed (tunnel lining)-soil coupling analysis model is established based on a structure dynamics theory, sensitivity index car body vertical acceleration a and the condition that the damaged fastener rigidity is 0 are introduced, and the sensitive index limiting value is calculated. The theoretical detection method can be suitable for single fastener damage and multiple fastener damage conditions.