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Early childhood development (ECD) is an essential foundation for children’s future development and a building block and driving force for society’s future development. Traditional evaluation models of early childhood development focus on children’s comprehensive evaluation, ignoring the importance of each evaluation data. In addition, the previous evaluation model mainly relies on the expert’s experience, which is highly dependent and has a strengthened subjectivity. Therefore, this paper combines the random forest algorithm to construct an early childhood development evaluation model and builds a multilayer evaluation index system. Test experiments show that the evaluation results obtained after the model’s training have a lower error than the traditional evaluation model, and the results are closer to the expected results. Application experiments show that the model can effectively present the evaluation results of children’s abilities and intuitively present comprehensive evaluation results, so that parents and teachers can view the corresponding evaluation data according to the needs of children’s development. At the same time, the evaluation results are consistent with the actual development of children, which can provide parents and teachers with effective and reliable evaluation data to improve children’s development program.

This paper constructs the evaluation index system of university teachers’ ethics from the hierarchical structure diagram of the evaluation system. In order to reduce the subjective feelings of the evaluators, a genetic algorithm is introduced to optimize the consistency test of the weights of the hierarchical analysis method. Taking ten colleges and universities in GD province as examples, the GAOHP-AHP model was used to calculate the index weights and then obtain the comprehensive evaluation scores of teacher ethics and teacher morality of each college and university. The results showed that the evaluation scores of ten universities were 3.975, 3.946, 4.075, and 4.078 for love for work, teaching and education, rigorous learning, and being a teacher, respectively. The overall evaluation scores of teacher Q in school 1 increased by 7.13% and 12%, respectively, compared with the other two teachers. This shows that the evaluation index system of teacher morality and teacher style in universities can effectively evaluate the teacher morale and teacher style quality of teachers.

Background and purpose: In the design of intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma, the traditional dose-volume (DV) physical optimization method is compared with the combined use of the DV physical optimization method and the generalized equivalent uniform dose (gEUD) optimization. This study aimed to investigate dosimetry differences in radiotherapy planning for nasopharyngeal carcinoma using gEUD method, to explore the effect of different optimization methods on the protection of organ at risk (OAR) in IMRT planning. Methods: Fifty patients with nasopharyngeal carcinoma in Eye & ENT Hospital of Fudan University from 2019 to 2021 were randomly selected, and two optimization plans were used for each case at the same time for optimization calculation. Group A used the traditional DV physical optimization method, while group B combined DV optimization and gEUD optimization methods adopted, in which gEUD was selected as a=1, 2, 5, 10 and 20. We evaluated the results of OAR dose data obtained by using different optimization schemes and different a values. Results: The planned data of the two plans were compared and analyzed, and there was no statistically significant difference in the dosimetry index of the target area between groups (P>0.05). However, in terms of the protection of the parotid gland and oral cavity, the results of the optimization plan of group B were significantly better compared with group A. The a value of gEUD had more obvious influence on the average dose of the parotid gland and the oral cavity. Conclusion: In the radiotherapy plan for nasopharyngeal carcinoma, the combined use of physical optimization and biological optimization can not only meet the target dose requirements but also better protect the parotid gland, oral cavity and other endangered OAR.

During the performance flight test at very high plateau,the helicopter is near the using limitation,the flight risk is high. It is necessary to study and develop reasonable and safe test flight methods to obtain accurate helicopter performance data while ensuring test flight safety. According to the airworthiness regulations on the requirements of helicopter high plateau test flight and data extrapolation,the required test flight environment condition and test flight subjects are analyzed and determined. Both of the very high plateau test flight method and data processing method are studied,and the determined test flight method is applied for very high plateau test flight of H425-100 helicopter. The results show that the testing methods determined in this paper are reasonable and feasible,in which the tethered hover method can improve the efficiency of test flight,the one-shot simulating mode can effectively reduce the risk of test flight,and the fitting method can be used to determine the helicopter take-off and landing distance more accurately.

Extensive experiments have demonstrated that fluid flow in low‐permeability media deviates from Darcy's law at low pressure gradients, which is called pre‐Darcy flow. Although numerous pre‐Darcy flow models have been proposed, these models generally contain one or more empirical parameters with no clear physical meaning. In this paper, we present a simple unified model to describe pre‐Darcy flow in porous media by introducing the concept of loss permeability. The physical meaning of the loss permeability parameter and its relationship to permeability are analyzed. Based on the statistics of the loss permeability parameter results of 24 core samples, we found that there is a good positive correlation between the loss permeability parameter and the absolute permeability. A smaller loss permeability indicates a stronger fluid‐solid interaction and a stronger nonlinearity between the flow velocity and the pressure gradient. Taking a one‐dimensional linear unsteady flow of a slightly compressible fluid in a homogeneous porous medium as an example, we solve the pressure diffusion equation based on the proposed model using a finite difference method. Our results demonstrate that the rate of pressure propagation for pre‐Darcy flow is slower than that for Darcy flow for the entire observation period, which corrects previous conclusions. This study is highly important for improving the understanding of fluid flow in low‐permeability media. Plain Language Summary: Pre‐Darcy flow usually occurs in low‐permeability media when the pressure gradient is very low. As the pressure gradient increases, the flow gradually transitions from the pre‐Darcy flow to Darcy flow. For a long time, pre‐Darcy flow and Darcy flow were described using two relatively independent equations, which is highly inconvenient. Because it is very difficult to accurately determine the critical pressure gradient between the pre‐Darcy flow and the Darcy flow, especially for the fluid flow in natural low‐permeability reservoirs. How to perfectly unify the pre‐Darcy flow and the Darcy flow in a simple and easy‐to‐use model is a scientific problem that has been researched for decades. Although several unified models have been proposed in recent years, they all contain one or more empirical parameters with no clear physical meaning. In this study, we propose a simple unified model to describe the flow from the pre‐Darcy flow to the Darcy flow in a porous medium by introducing the concept of loss permeability. Then, we discuss the relationship between the loss permeability parameter and permeability based on a series of experimental data from published papers. Finally, we analyzed the pressure propagation feature for a one‐dimensional linear unsteady flow of a slightly compressible fluid in a homogeneous porous medium. Key Points: A simple unified model is proposed to describe the flow from pre‐Darcy flow to Darcy flow by introducing the concept of loss permeabilityThe physical meaning of the loss permeability parameter and its relationship to permeability are analyzedThe pressure propagation characteristics of pre‐Darcy flow and Darcy flow at the field scale are analyzed [ABSTRACT FROM AUTHOR]