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The stability of foundation pit slopes is a key concern during the construction of foundation pits. The deformation and instability of slopes will pose a major threat to the safety of foundation pits construction. Based on the foundation pit project of Shenzhen Dapeng People’s Hospital, this study uses DJI phantom 4 RTK drone to collect oblique photography data of the foundation pit in different periods, reconstructs high-precision 3D virtual models through the Bentley ContextCapture software and generates the Digital Surface Model (DSM) data. The model quality report shows that the accuracy of the three-dimensional model is better than 5 cm, up to about 1 cm. Spatial analysis of DSM data in different periods using ArcGIS can obtain the deformation of the foundation pit slopes. This method can also be used for the calculation of earthwork excavation of the foundation pit, which can effectively reduce the field workload of traditional earthwork surveys.

In order to solve the problem of installation and measuring errors in the profile evaluation of large parabolic antennas, this paper proposes a new method for evaluating the profile of large paraboloidal antennas based on genetic algorithm and least square method. This method can effectively realize the adaptive adjustment of the measured points and the theoretical contour in the process of evaluating profile, which can eliminate the position error between the measured points and the theoretical contour that influences on the results of the profile evaluation. The availability of this method has been proved by simulation.

Abstract.In order to ensure higher accuracy and better electrical performance of large antennas in future,this paper does some research for deformation of antenna’s reflector:modeling for 25m antenna and reappearing deformation when elevation changes every 15° just considering gravity by using ANSYS.Using results of simulation obtains deformation error curves with elevation changes, creates the conditions for compensating distortion and has a certain value. By using Ruze formula, deeply studies the regular about antenna’s electrical performance influenced by deformation because of elevation changes,obtains meaningful data and tables of relationship between elevation and parameters of electrical performance in nine bands of 25m antenna.It finds out that when working in high-frequency band, efficiency and gain loss of antenna will be more affected by elevation angle changes.Finally creates conditions for optimizing antenna parameters and performing high reliability tasks such as deep space exploration and aerospace communication.