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BackgroundGaussian signals have symmetry and completeness, hence, the Gaussian filtering method is widely used in nuclear signal processing and radiation energy spectrum analysis. The mathematical description of Gaussian signals is relatively complex, which makes it difficult to construct digital Gaussian pulse shaping filters for nuclear pulse signal real-time processing. The commonly used digital quasi-Gaussian shaping algorithm in radiation measurement systems is derived from the differential equations of Sallen-Key and CR-(RC)n filters in analog nuclear electronics. However, its output shaping pulse signals have poor symmetry and problems such as undershoot occur when used in a single stage.PurposeThis study aims to explore the convolutional quasi-Gaussian pulse shaping filter algorithm and apply it to the processing of X-ray fluorescence measurement system experimental platform to obtain measured nuclear pulse data.MethodsFirstly, a convolutional quasi-Gaussian pulse shaping algorithm was implemented based on trapezoidal pulse signals, and bipolar pulse shaping was achieved after the initial convolution. Then, the second convolution was accumulated and summed to obtain left and right symmetric quasi-Gaussian shaping pulses. The digital recursive formula of the quasi-Gaussian pulse shaping algorithm was obtained using the Z-transform method, and the effectiveness of the algorithm and the influence of shaping parameters on the amplitude frequency characteristics were studied through simulation. Finally, quasi-gaussian shaping algorithm and trapezoidal shaping algorithm were applied separately to the offline process of measured nuclear pulse data from the X-ray fluorescence measurement system experimental platform.ResultsThe quasi-Gaussian pulse shaping filter has better high-frequency noise suppression performance compared to trapezoidal pulse shaping filters. With the increase of the values of shaping parameters na and nc, the filter passband decreases whilst the low-frequency amplitude relatively increases, and the high-frequency noise suppression effect is enhanced. However, this also leads to shaping pulse broadening and increases the probability of pulse pile-up.ConclusionsThe experimental results demonstrate that the quasi-Gaussian pulse shaping algorithm has better pile-up pulse separation ability. Under identical X-ray tube voltage and current conditions and peaking time, the energy resolution of the energy spectra obtained by both algorithms is fundamentally equivalent. However, the energy spectrum with quasi-Gaussian pulse shaping has a higher characteristic peak area.

With the rapid development of digital technology, the digital system based on the fuzzy kano model provides a digital strategy for new media art exhibition museum information dissemination, digital display, and other fields. In this paper, the fuzzy Kano model is used to design the digital museum, and the system design starts from the five elements of user experience. The digital system is designed from the levels of the strategy layer, scope layer, structural layer, framework layer, and performance layer, respectively. Clustering the sensors first is used to obtain the functional area in the classification of audience behavior. The optimal clustering results can be achieved through spectral clustering of sensor graphs. Clustering is proposed using the typical movement pattern extraction algorithm. Optimization indexes are set to achieve optimal typical movement patterns. The auxiliary sensors capture the interactive movements of the audience with the artwork and collect logical information. Behavioral pattern templates for various types of viewers are constructed using viewer attribute labels. In the user classification method based on behavioral patterns, edges in the graph are used as features, and an optimization problem is constructed to solve the importance of each feature for audience classification. The implementation of interactive features greatly enhances the interactive experience of the audience. It makes the audience’s novelty evaluation score of the system reach 8.671. The classification algorithm based on the behavioral model performs well in all evaluation indexes, which indicates that the system proposed in this paper meets the audience’s digital and interactive needs for new media art exhibitions.

By analyzing the multimodal grammar of films, the deeper concepts that the designers want to express can be better conveyed to the audience, and the expectations of the moviegoers can be enhanced. Therefore, based on the analysis of the classic Zhang Delu’s comprehensive theory of multimodal discourse, the article proposes the multimodal discourse analysis framework used in this paper to explore the ideologies implied in the text and images of movie subtitles and the images they construct and the inspirational meanings they draw from. It is found that among the 150 clauses in the corpus analysis, 28% are material processes, 22% are mental processes, 12% are verbal processes, 14.67% are relational processes, 17.33% are behavioral processes, and 4.67% are existential processes. Through multimodal grammar analysis, the discourse tendencies of the traditional culture-adapted movie can be effectively grasped.

In this paper, according to the concept of multivariate composite function, the limit and continuity conditions of multivariate composite function are given, and the continuity relationship between the inner function and the outer function of the composite function at the same point is investigated. The relationship between the limit and continuity of a composite function composed of two functions at the same point is investigated by examples, while some limit results are explained from the perspective of composite functions, and the limit calculation law of multivariate composite functions is proposed. Using the consistent central limit theorem in the limit calculation law, the absolute value and limit of the interval of the multivariate composite function are obtained, and the iterative limit of the variational reduction approximation method is confirmed by combining the absolute value and limit of the interval of the multivariate composite function. On the basis of the application of limit operation of a multivariate composite function, the limit distribution of high-dimensional likelihood ratio statistics of multivariate composite function is analyzed by using data simulation analysis. The results show that both limit distributions have better simulation results when p are small, such as p = 5 or p = 10, but the traditional limit is better than the normal limit, indicating that the results of multivariate composite function limit calculations have good accuracy. A method for solving the limits of multivariate composite functions is proposed in this study, which is of great theoretical and practical significance in the study of higher mathematics.