In the Computational Fluid Dynamics (CFD) simulation for building structures, it is important to generate a stable atmospheric boundary layer (ABL) flow field that meets the standards. In this paper, the wind profile, turbulence intensity, and wind velocity power spectrum in the target region of a numerical wind tunnel were accurately simulated by a hybrid method. With the numerical simulation software FLUENT, the hybrid simulation method was implemented. In the hybrid simulation method, the wind field was simulated by setting the roughness element in the upstream of the model, adding random disturbance, and setting the circulation surface. The influences of simulation parameters (such as roughness element and random number parameters) and FLUENT solution methods on the flow field results were studied. The results show that the influence range of the roughness element on turbulence intensity is approximately 6 times its physical height. The turbulence intensity is positively correlated with the standard deviation of random numbers and negatively correlated with the assignment height. Finally, the wind fields for different terrains satisfying the standards were obtained in numerical wind tunnels. A simulation of the wind pressure on an inflatable membrane structure was illustrated. The comparison between numerical and experimental results shows a good accordance, which indicates a desirable potential in practical application.

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In the field of natural language processing, language-based question answering has been widely studied and made great achievements. As an important form of search engine, question answering system can further improve the search quality compared with traditional search engines. Traditional tree-based indexing methods are inefficient in high-dimensional space. This paper focuses on the application of k nearest neighbor search in large-scale image databases, and researches on high-dimensional indexing technology based on vector approximation method. Fast-Hessian detector is used to detect feature points and generate SURF feature description vector; Then, the initial matching point pair is obtained by fast approximate nearest neighbor search algorithm, and then the unidirectional matching results are matched bidirectionally; at the same time, it makes a detailed analysis of the situation that the events in the sentences are verbs of “abstract change”, so as to realize the automatic question and answer after the change of abstract relations between entities.