30 results about "Solar Activities" patented technology

The invention discloses an ionosphere TEC forecasting method, system, medium and equipment fused with a geomagnetic field, and belongs to the field of ionosphere TEC forecasting, the method comprises the following steps: obtaining current ionosphere TEC grid data, solar activity index data and global geomagnetic field observation data, and constructing to obtain multi-channel fusion data; based on a preset ConvLSTM model, processing the multi-channel fusion data, and outputting an ionized layer TEC forecast result; wherein the ConvLSTM model is obtained by training an input sequence in historical multi-channel fusion data and a corresponding target sequence; the input sequence is composed of multi-channel fusion data of a plurality of consecutive time steps, and the target sequence is composed of ionized layer TEC grid data immediately after the input sequence. By implementing the method, the forecasting precision of the ionized layer TEC under complex space weather conditions such as magnetic storm can be improved.

The invention discloses a regional ionosphere temporal-spatial resolution refinement method, which comprises the following steps: acquiring real-time GIM data, a solar activity index and a geomagnetic activity index, inputting the data into a trained forecasting model, and outputting a VTEC mean value of a grid center point; calculating an STEC value based on the output VTEC mean value; the training of the forecasting model comprises the following steps: acquiring original GIM data and CORS observation value data, and respectively preprocessing the original GIM data and the CORS observation value data to obtain GIM-VTEC calculated based on the GIM data and puncture point VTEC calculated based on the CORS observation value data; the GIM-VTEC obtained through preprocessing and the puncture point VTEC are matched according to the time and the grid range; acquiring a solar activity index and a geomagnetic activity index, matching the solar activity index and the geomagnetic activity index with the matched VTEC data according to time, and constructing a training sample set; constructing a BP neural network, taking time, longitude, latitude, GIM-VTEC, a solar activity index and a geomagnetic activity index as input, and taking a puncture point VTEC obtained by calculating CORS observation value data as output; and training is carried out on the constructed training sample set, and a trained forecasting model is output.

The application discloses a flare occurrence position determination method and device, electronic equipment and computer medium. The method comprises the following steps: when it is determined that a flare occurs, a flare peak time, a full-disk image corresponding to the flare peak time and initial disk positions of each solar active region are obtained; according to the flare peak time and the initial disk positions of each solar active region, first disk positions of each solar active region corresponding to the flare peak time are determined; the first disk positions of each solar active region are subjected to coordinate system conversion, and pixel positions of each solar active region in the full-disk image are determined; according to the pixel positions of each solar active region and the full-disk image, first pixel values of regions in which each solar active region is located in the full-disk image are respectively calculated; and the first disk position of a solar active region corresponding to a maximum value is determined as the occurrence position of the flare. The application can accurately determine the occurrence position of the flare when the flare occurs.

This invention discloses a method for refining the spatiotemporal resolution of the regional ionosphere, comprising: acquiring real-time GIM data, solar activity index, and geomagnetic activity index and inputting them into a trained forecast model, outputting the mean VTEC value of the grid center point; calculating the STEC value based on the output mean VTEC value; training the forecast model includes: acquiring raw GIM data and CORS observation data and preprocessing them respectively to obtain GIM-VTEC calculated based on GIM data and puncture point VTEC calculated based on CORS observation data; matching the preprocessed GIM-VTEC and puncture point VTEC according to time and grid range; acquiring solar activity index and geomagnetic activity index and matching them with the matched VTEC data according to time to construct a training sample set; constructing a BP neural network with time, longitude, latitude, GIM-VTEC, solar activity index, and geomagnetic activity index as inputs, and puncture point VTEC calculated from CORS observation data as output; training on the constructed training sample set and outputting the trained forecast model.

The invention discloses an information display method and device, electronic equipment and a readable storage medium, and belongs to the technical field of electronic equipment. The method comprises the following steps: determining meteorological information corresponding to a first position according to position information of the first position; the weather information comprises at least one of sun activity information and moon activity information; and displaying the meteorological identifier according to the meteorological information corresponding to the first position.

The invention provides an ionosphere parameter and short wave frequency band prediction method and electronic equipment, and the method comprises the steps: obtaining the ionosphere parameter data in a corresponding IRI model above the midpoint of a great circle through obtaining the geographic coordinates of two places of a communication link and the midpoint of the great circle, obtaining the geomagnetic solar activity data of an open-source data website, and obtaining the geomagnetic solar activity data of the open-source data website; the method comprises the following steps: carrying out ionosphere oblique detection by using ionosphere detectors at two communication places, obtaining an ionosphere oblique detection ionogram, obtaining frequency band data available for short-wave communication from the oblique detection ionogram, carrying out data preprocessing, selecting different tasks, setting corresponding Transform-LSTM model hyper-parameters, carrying out model training, and storing optimal model parameters; and performing an ionosphere parameter prediction task or a short-wave communication available frequency band prediction task by using the corresponding model. The ionosphere detection data, the environment monitoring data and the like are fused in the deep learning field and the short-wave communication field, and the method has important significance and application prospects.

The application discloses a method for predicting long-term solar activity level, comprising the following steps: S1, establishing a solar activity level prediction model; S2, establishing a relative sunspot number monthly average database; S3, obtaining a target prediction month; S4, using an RBF neural network to predict the relative sunspot number yearly moving monthly average of the target prediction month and the following n months, and filling in the relative sunspot number monthly average database; S5, traversing the relative sunspot number monthly average database to obtain the relative sunspot number monthly average data of the target prediction month and the previous several months; S6, substituting the relative sunspot number monthly average data of the target prediction month and the previous several months into the solar activity level prediction model; and S7, outputting the relative sunspot number yearly moving monthly average and the prediction result thereof. The application can accurately predict the relative sunspot number yearly moving monthly average of the current month and the following months, and can be used as a reference basis for the solar activity level and an input parameter for the prediction of other related parameters.

The invention discloses a 4K solar extreme ultraviolet image prediction model construction method based on BandSwinUnet, and relates to the technical field of solar observation and space weather forecast, and the method comprises the following steps: S1, screening original data, and processing the data to obtain training data; s2, segmenting the calculation task and the weight in parallel by using an operator, and dividing the calculation task and the weight to a plurality of devices to execute the calculation task; s3, acquiring a device number, uniformly dividing training data to a plurality of devices, independently completing forward propagation and back propagation calculation by each device, and synchronizing gradients; s4, building a BandSwinUnet model on each device, and training the BandSwinUnet model based on the data in the step S1 and the parallel strategy set in the step S2; and S5, analyzing and optimizing the model in combination with errors. The problems that when an existing method is applied to 4K-resolution image prediction, the model generalization ability is insufficient, the adaptability to specific solar activity conditions is poor, and the calculation complexity is extremely high are solved.

A building automation system includes a ceiling-mounted sensor module comprising a millimeter-wave radar sensor, thermal array sensor, and ambient light sensor. The millimeter-wave radar sensor detects stationary occupants by measuring chest movements corresponding to breathing patterns and generates three-dimensional position coordinates for each detected occupant. A control unit processes sensor data locally and automatically controls a lighting system, window covering system, climate control system, and audio system based on occupancy patterns and environmental conditions. The control unit adjusts lighting brightness and color temperature according to a solar schedule determined from GPS coordinates and time of day, and prevents lighting activation when ambient light levels exceed a predetermined threshold despite detected occupancy. The system operates independently during network disruptions through local data processing within the residential structure.

The invention discloses a flare occurrence position determination method and device, electronic equipment and a computer medium. The method comprises the following steps: when it is determined that a flare occurs, acquiring flare peak time, a full-solar-surface image corresponding to the flare peak time and an initial solar-surface position of each solar active area; according to the solar flare peak time and the initial solar surface position of each solar active area, determining a first solar surface position corresponding to each solar active area at the solar flare peak time; performing coordinate system conversion on the first solar surface position of each solar activity area, and determining the pixel position of each solar activity area in the full solar surface image; according to the pixel position of each solar activity area and the full-solar-surface image, respectively calculating a first pixel value of each solar activity area in an area where the full-solar-surface image is located; and determining the first solar surface position of the solar active area corresponding to the maximum value as the occurrence position of the flare. According to the invention, the occurrence position of the flare can be accurately determined when the flare occurs.

The application discloses a method for calculating foF2 affected by weak geomagnetic activity and relates to the technical field of ionospheric physical research and application. The method comprises the following steps: acquiring an Ap index and a Dst index, wherein the Ap index and the Dst index satisfy a first condition; acquiring an ionospheric solar activity index S by processing an F10.7 index; calculating a solar activity influence value T by using a Fourier polynomial; acquiring an actual observation value R; and acquiring a weak geomagnetic activity influence value G by using the actual observation value R and the solar activity influence value T. The method can effectively separate the influence of weak geomagnetic activity on foF2 when studying foF2 by improving the F10.7 index and further putting forward the ionospheric solar activity index S, and is favorable for more directly studying the influence of weak geomagnetic activity on foF2 and the ionosphere. The method is easy to operate, simple in data selection and easy to realize.

The application discloses a method for extracting middle layer top temperature multi-period characteristics and analyzing influencing factors, and belongs to the technical field of atmospheric detection and meteorological data analysis. The method first extracts time series data of the middle layer top temperature based on the 90km height and the lowest temperature point standard, then completes time domain trend and mutation analysis through seasonal departure and Mann-Kendall test, adopts discrete wavelet decomposition to obtain four main oscillation periods of 3 years, 7 years, 11 years and 22 years, then uses continuous wavelet to obtain the length of the fine-calibrated period, and finally performs cross wavelet analysis on the quasi-biennial oscillation, the El Nino effect and the solar activity index to obtain the final correlation and time lag results. The application realizes joint time-frequency domain analysis of discrete wavelet transform, continuous wavelet transform and cross wavelet transform, effectively improves the cycle recognition accuracy, quantifies the multi-scale correlation and time sequence hysteresis of each factor, and provides a new research idea for high-altitude atmospheric climate influencing factor analysis.

The application discloses a method for stabilizing a full-disk extreme ultraviolet time sequence image of the sun, and relates to the technical field of solar observation image processing. The method comprises the following steps: acquiring a full-disk extreme ultraviolet time sequence image of the sun, and extracting gradient information of each frame of image; determining a solar edge region of each frame of image based on the gradient information; calculating a regional gradient difference value of a frame to be stabilized and a reference frame in the solar edge region, and minimizing the regional gradient difference value to obtain a first offset; extracting a matching point pair between the two frames; adjusting the matching point pair based on the first offset, determining an offset change amount based on a residual of the matching point pair and a matching point pair weight, and obtaining a second offset; and compensating the frame to be stabilized by using the second offset to obtain a stabilized frame. The application significantly suppresses the problems of mismatching and error accumulation caused by the rapid evolution of the solar active region by combining gradient difference minimization and anti-difference selection weight iteration optimization of the matching point pair, and improves the robustness and accuracy of the stabilization processing.

The invention discloses a method for calculating the electron density of a large-scale structure of a medium weft slot in an ionized layer. The method comprises the following steps: step 1, determining calculation time and a maximum value of the strength of the medium weft slot; step 2, acquiring solar activity data and geomagnetic activity indexes; 3, calculating the electron density of the background ionized layer when the weft slot structure in the ionized layer is not considered; 4, determining the latitude position of a latitude slot in the ionized layer; 5, calculating the zenith angle of the sun; and step 6, determining the longitude position of the weft slot in the ionized layer. According to the method, the influence of the solar geomagnetic activity on the ionosphere midlatitudinal slot is fully considered, the electron density distribution model considering the midlatitudinal slot structure is constructed according to the midlatitudinal slot electron density spatial-temporal change rule obtained through early-stage data statistical analysis, and the calculation precision of an ionosphere model in a related region is effectively improved.

This invention discloses a method for reconstructing the peak electron density of the ionosphere, comprising: S1, constructing a peak electron density reconstruction neural network SRON2NN model, which adopts a fully connected feedforward neural network and includes an input layer, several hidden layers, and an output layer; S2, constructing and introducing key physical features, including effective solar radiation EUV×cosχ and thermosphere ΣO / N2; S3, training the model using ionospheric F2 layer peak electron density NmF2 data, time information, geomagnetic index Dst, solar activity index F10.7, effective solar radiation EUV×cosχ, and ΣO / N2 obtained from COSMIC-1 radio occultation observations; S4, reconstructing and verifying the ionospheric F2 layer peak electron density NmF2 based on the trained SRON2NN model. This invention achieves high-precision and interpretable reconstruction of the ionospheric F2 layer peak electron density NmF2 globally by explicitly introducing effective solar radiation and thermosphere ΣO / N2.

The application discloses a method, device, medium and product for predicting the total electron content of the ionosphere, which comprises the following steps: acquiring geomagnetic disturbance data of a region where a single-station global navigation satellite system is located, wherein the geomagnetic disturbance data comprises a magnetic north component and a magnetic east component; calculating the horizontal geomagnetic disturbance intensity based on the magnetic north component and the magnetic east component; inputting the horizontal geomagnetic disturbance intensity, the geomagnetic disturbance data, the acquired solar activity index and the historical observation sequence of the total electron content into a preset prediction model, so as to obtain a plurality of subspace attention features through a multi-head attention mechanism, and to obtain an encoding feature matrix through linear change processing; decoding the encoding feature matrix through a decoder of the prediction model to obtain a context vector, and performing autoregressive processing on the context vector until a target total electron content prediction sequence is obtained. The application can improve the prediction accuracy of the total electron content in the ionosphere above the single-station global navigation satellite system.

The application provides a low-orbit satellite mobile communication ground experiment method and system. According to the influence of different orbit heights and solar activity periods, a diversified orbit parameter set is planned to generate a virtual satellite network model; based on the virtual satellite network model, an optimal transmission path is calculated by using a path prediction algorithm, the characteristics of the transmitted signal are adjusted through real-time channel simulation technology, and a low-orbit satellite communication environment test scene is generated; based on the low-orbit satellite communication environment test scene, a self-adaptive performance evaluation algorithm is used to evaluate communication performance data, an energy efficiency optimization method is used to determine a power consumption mode, the relationship between battery consumption and communication quality is analyzed, and a performance evaluation report is generated; the power consumption data and the communication quality data are integrated, and after integration, the integrated data are converted into a practical solution, and a low-orbit satellite mobile communication ground experiment result is generated. The technical scheme provided by the application improves the comprehensiveness and practicality of the low-orbit satellite mobile communication ground experiment method.

The application discloses a method for analyzing the influence of global ionospheric scintillation on GPS positioning performance during geomagnetic storm, which belongs to the technical field of satellite navigation and space weather. Based on the obtained data of GPS stations and moderate geomagnetic storm events in the solar activity cycle, the global ionospheric scintillation intensity is calculated by using the elevation angle weighted average ROTI, and the PPP-AR solution and positioning performance index are extracted. The correlation between the global average ROTI and the minimum value of the geomagnetic index during the main phase of the geomagnetic storm event is statistically analyzed, and the linear correlation between the global average ROTI and the total number of cycle slips is statistically analyzed. The correlation between the elevation angle weighted average ROTI and the three-dimensional PPP relative residual and the fixed satellite ratio is analyzed, and the latitude-dependent response law and time delay characteristics of ionospheric scintillation and positioning accuracy reduction during the geomagnetic storm are analyzed. The method is accurate in analysis, effectively reveals the differential response law of different latitude regions, and provides statistical basis for the space weather warning of dynamic high-precision GNSS positioning.

The invention relates to the technical field of meteorological monitoring, and discloses a rainfall forecasting method and device considering space and time, a medium and equipment, and the method comprises the steps: integrating multi-source data which is the data obtained by fusing meteorological monitoring data, solar activity monitoring data and space environment monitoring data; according to the method, the spatial prediction precipitation amount set, the short-term / medium-term / long-term spatial-temporal prediction precipitation amount set and the multi-scale fusion spatial-temporal prediction precipitation amount set are obtained in sequence, the correlation of space and time is comprehensively considered in the process, the precision of rainfall prediction is effectively improved, the change rule of rainfall at different spatial positions along with time can be reflected more accurately, and the accuracy of rainfall prediction is improved. And a more reliable support is provided for meteorological monitoring and disaster early warning of plateau mountain areas.

The invention discloses a solar flare forecasting method and system based on fusion of physical parameters and geometric features of an active area. The method comprises the following steps: acquiring magnetic field observation data and optical image data of a target solar active area; extracting magnetic field physical parameters from the magnetic field observation data, and extracting geometric features of an active area from the optical image data; acquiring magnetic field observation data and optical image data of the target solar active area in a historical time window, and constructing a time sequence of magnetic field physical parameters and geometric features; extracting dynamic evolution characteristics of physical parameters and geometric characteristics of the magnetic field from the time sequence; fusing the physical parameters and the geometric features of the current magnetic field with the dynamic evolution features, and constructing an enhanced fusion feature vector; inputting the enhanced fusion feature vector into a pre-trained neural network model, and obtaining a prediction probability of generating a specific-level flare in the target solar activity area in the future; and generating and issuing flare forecast information according to a comparison result of the forecast probability and a preset threshold value.

The present application relates to the field of astronomical, space science and solar observation coronagraph instrument, especially relates to a kind of external mask type image stabilization coronagraph, it includes in turn: external mask, heat rejection mirror, objective lens group, field stop, field lens, Lyot diaphragm, image converter group and linear polarizer, it further includes: image stabilization device, the image stabilization device includes: image stabilization lens group, guide mirror and image stabilization lens adjusting mechanism, wherein, the image stabilization lens group is located between objective lens group and field stop;The guide mirror is set to the incident light path direction parallel to external mask outside external mask, for collecting solar azimuth and solar elevation angle optical signal, obtains solar pointing deviation signal;The image stabilization lens adjusting mechanism is based on solar pointing deviation signal, adjusts the pose of image stabilization lens group, to compensate solar pointing deviation.The present application combines high-precision imaging and image stabilization technology organically, significantly improves the observation performance of coronagraph, provides reliable technical support for the research of solar activity and coronal structure.

This invention discloses a method for quantifying the memory time of solar extreme ultraviolet radiation based on ionospheric electron density. The method comprises: S1, constructing an EDPRNN; S2, inputting historical solar extreme ultraviolet (EUV) radiation, solar activity index, geomagnetic index, time, and altitude information into the EDPRNN, and optimizing it through a loss function to learn the memory time parameter τ for each altitude layer. i S3. Utilize LSTM layers to extract temporal features of historical solar radiation sequences, and then weight them using a Gaussian kernel module based on the learnable and memorizable time parameter τ. i The invention employs a multilayer perceptron (MLP) to weight temporal features, simulating the decay memory of electron density over historical radiation. In step S4, a one-dimensional convolutional module captures high-dimensional structural features, and a preliminary electron density profile is output by the MLP. A smoothing module enhances the vertical continuity of the profile through residual connections, completing the reconstruction of the ionospheric electron density profile. In step S5, the memory time of each altitude layer is extracted and quantified to obtain the distribution of ionospheric electron density memory time to solar EUV radiation. This invention achieves high-precision reconstruction of the ionospheric electron density profile and quantitative extraction of solar radiation memory time.

This application discloses a plasma model analysis method and apparatus for space charging and discharging effects. The method includes: determining the orbit type and the space region traversed during on-orbit operation; determining the plasma model of the outer space plasma fusion model in the traversed space region; obtaining plasma parameters of the traversed space region based on data from the current solar activity period and / or the current geomagnetic activity period; analyzing the charging and discharging effects occurring on the spacecraft surface based on the plasma parameters; using an intrinsic plasma model in the intrinsic region and a transitional fusion model in the transition region, determining the range of the transition region based on the boundary between two adjacent intrinsic regions; dividing the transition region into multiple sub-regions based on the range and division strategy of the transition region; determining the fusion mode of each sub-region for each sub-region, obtaining a transitional fusion model corresponding to the transition region. The plasma parameters obtained through plasma model analysis are more accurate.

The invention belongs to the technical field of ionosphere total electron content forecasting, and relates to a global ionosphere total electron content forecasting method and system based on a graph neural network, and the method comprises the steps: obtaining global ionosphere TEC data of the first 24 hours; obtaining geomagnetic and solar activity index data of the first 24 hours; carrying out sequence conversion and stacking on the obtained data; inputting the stacked data into a pre-trained graph neural network to obtain a prediction result of the global ionosphere TEC in the next 24 hours; the graph neural network simulates the three-dimensional spherical surface of the ionized layer, adopts an encoder-processor-decoder architecture, and introduces a regular icosahedron and a subdivided regular polyhedron thereof to simulate local and global information transmission of the electron content of the ionized layer. According to the method, a regular polyhedron structure is introduced, three-dimensional spherical simulation is directly carried out by utilizing the graph neural network, and a relatively good prediction effect is achieved in a geomagnetic quiet period or a magnetic storm period.

The invention relates to the technical field of meteorological monitoring, and discloses a rainfall forecasting method and device considering time and geography, a medium and equipment, and the method comprises the steps: integrating multi-source data which is the data obtained by fusing meteorological monitoring data, solar activity monitoring data and space environment monitoring data; according to the method, the correlation between time and geography is comprehensively considered in the process, so that the precision of rainfall forecasting is effectively improved, the rainfall at other geographic coordinate positions except the monitoring station in the preset area can be accurately predicted, and the accuracy of rainfall forecasting is improved. And timely and comprehensive meteorological information support is provided for disaster early warning and disaster-resisting and emergency rescue work in plateau mountainous areas.

The invention discloses an ionosphere prediction method and device based on a white spectrum method and deep learning, and belongs to the technical field of intersection of spatial physics and satellite navigation, and the method comprises the steps: carrying out the preprocessing of multi-source observation data, obtaining time series data, carrying out the white spectrum method analysis of the time series data, and obtaining a disturbance time series; processing the disturbance time sequence to generate a global solar activity level index, a middle and low latitude geomagnetic disturbance index and a polar region geomagnetic disturbance index; the indexes and satellite inversion data serve as input, a deep learning reconstruction model formed by a multi-layer full-connection feedforward neural network is adopted, and ionosphere four-dimensional electron density distribution is output; ionized layer four-dimensional electron density distribution and total electron content observation data serve as input, a space-time prediction model is adopted, and an ionosphere prediction result at the future moment is output. The problems that a traditional spatial index is poor in timeliness and low in resolution and cannot effectively capture the complex time-space characteristics of the ionized layer can be solved.

The invention discloses a moon shadow time calculation method based on an SGP4 model, and relates to the technical field of spacecraft orbit dynamics and energy management.The moon shadow time calculation method comprises the steps that a closed feedback loop is formed by extending a Kalman filter state variable and taking the instantaneous noise offset of an atmospheric resistance parameter B * as an independent estimation target; orbital perturbation changes caused by sun activity peaks, sudden geomagnetic disturbance and the like can be tracked in real time, and the stability of penumbra entering and exiting time of the near-earth satellite is remarkably improved; in order to solve the problem of frequent switching of shadow intervals of high-orbit satellites, a time period merging strategy based on an error ellipsoid and shadow area overlapping probability is provided. By quantizing the contribution of the position uncertainty to the shadow state, a pseudo switching event generated by model jitter is filtered out, a continuous shadow time period conforming to engineering practice is output, and invalid operation of an energy system is reduced.

The invention discloses an image stabilization method for a full-sun extreme ultraviolet time sequence image, and relates to the technical field of sun observation image processing, and the method comprises the steps: obtaining the full-sun extreme ultraviolet time sequence image, and extracting the gradient information of each frame of image; determining a sun edge area of each frame of image based on the gradient information; calculating a regional gradient difference value of the to-be-stabilized image frame and the reference frame in the sun edge region, and minimizing the regional gradient difference value to obtain a first offset; extracting matching point pairs between the two frames; adjusting the matching point pair based on the first offset, and determining the offset variation based on the residual error of the matching point pair and the weight of the matching point pair to obtain a second offset; and compensating the to-be-stabilized image frame through the second offset to obtain the stabilized image frame. Through combination of gradient difference minimization and anti-error selection weight iterative optimization of the matching point pair, the problems of mismatching and error accumulation caused by rapid evolution of the solar active region are remarkably suppressed, and the robustness and accuracy of image stabilization processing are improved.

The invention relates to a method for calculating the electron density of plasma cloud blocks of an ionized layer in the arctic region. The method comprises the following steps: step 1, determining calculation time and parameters of the plasma cloud blocks; step 2, acquiring solar activity data and geomagnetic activity indexes; 3, calculating background ionized layer electron density distribution when the ionized layer plasma cloud block structure is not considered; and step 4, determining an ionized layer plasma cloud block distribution area. According to the method provided by the invention, the influence of solar geomagnetic activity on the plasma cloud block of the ionized layer is fully considered, the spatial-temporal change rule of the structure is obtained according to early-stage data statistical analysis, the defect of an existing ionized layer model in plasma cloud block description is overcome, and an electron density distribution model considering the plasma cloud block is constructed; the precision of the ionosphere model is improved, the performance of a communication and navigation system is optimized, and the application effect of the ionosphere model in related fields is improved.