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With the gradual increase in the difficulty of competitive martial arts, athletes must complete fine, stable, high-quality and difficult movements in order to achieve excellent performance. The real-time extraction of martial arts movements is a topic that many martial arts enthusiasts care about. This research mainly discusses the real-time extraction and simulation of VR image targets of martial arts routine difficulty action technology. Considering the complex characteristics of martial arts movements, this article will analyze the preprocessing content of existing images. This includes image enhancement and image filtering, and uses median filtering methods to enhance the characteristics of the collected images. In this way, the visual effect of the original image can be improved, and the processed image will contribute to the subsequent segmentation. A new image segmentation method is proposed for the color model of the image. According to the H component of the HSV model representing the characteristics of chromaticity, the color image is transformed into the HSV model, and the H component is extracted. The histogram concept applies to H components. Based on the histogram of the H component, the segmentation threshold is determined, and the cropping target in the image is detected. Because the model space is very sensitive to color, VR technology is used to automatically determine the segmentation target. Combined with the above division methods, the automatic extraction of objects in the image is completed. The method of using VR technology for image extraction processing has high precision, and the error value is 3.92%<5%. The research results show that the VR segmentation results are good, suitable for image segmentation in complex backgrounds and automatic image extraction in complex backgrounds.

Objectives: Delayed neurocognitive recovery (DNR) seriously affects the post-operative recovery of elderly surgical patients, but there is still a lack of effective methods to recognize high-risk patients with DNR. This study proposed a machine learning method based on a multi-order brain functional connectivity (FC) network to recognize DNR.Method: Seventy-four patients who completed assessments were included in this study, in which 16/74 (21.6%) had DNR following surgery. Based on resting-state functional magnetic resonance imaging (rs-fMRI), we first constructed low-order FC networks of 90 brain regions by calculating the correlation of brain region signal changing in the time dimension. Then, we established high-order FC networks by calculating correlations among each pair of brain regions. Afterward, we built sparse representation-based machine learning model to recognize DNR on the extracted multi-order FC network features. Finally, an independent testing was conducted to validate the established recognition model.Results: Three hundred ninety features of FC networks were finally extracted to identify DNR. After performing the independent-sample T test between these features and the categories, 15 features showed statistical differences (P &lt; 0.05) and 3 features had significant statistical differences (P &lt; 0.01). By comparing DNR and non-DNR patients’ brain region connection matrices, it is found that there are more connections among brain regions in DNR patients than in non-DNR patients. For the machine learning recognition model based on multi-feature combination, the area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, and specificity of the classifier reached 95.61, 92.00, 66.67, and 100.00%, respectively.Conclusion: This study not only reveals the significance of preoperative rs-fMRI in recognizing post-operative DNR in elderly patients but also establishes a promising machine learning method to recognize DNR.

This paper builds a students’ physical health influencing factors analysis model based on the SOM network. First, Analytic Hierarchy Process (AHP) is adopted to confirm the weighted value of various indexes of students’ physical health influencing factors. One fourth of the weighted value of various indexes is adopted as the gradient to divide students’ physical health grades and periods, and as the input training samples for the SOM network. Following that, the SOM network after training is analyzed for its sensitivity towards factors influencing physical health. Results suggest that: (1) Duration and intensity of physical exercise is a deciding factor. According to the simulated results, a student with disqualified physical health can recover to a sound state by ensuring the index value of the above deciding factor to be above 0.6. (2) In terms of a student with good physical health, when duration and intensity of his physical exercise is “0”, his physical health will be disqualified. In order to maintain the sound physical health, the index value of duration and intensity of his physical exercise must be above 0.3.