Abstract: A liquid crystal antenna and a method for forming a liquid crystal antenna are provided. The liquid crystal antenna includes a first substrate; a second substrate opposite to the first substrate; and a liquid crystal layer disposed between the first substrate and the second substrate. A first conductive layer is disposed on a side of the first substrate facing toward the second substrate; a second conductive layer is disposed on a side of the second substrate facing toward the first substrate; the second conductive layer at least includes a plurality of radiation electrodes; an external metal layer is disposed on a side of the first substrate facing away from the liquid crystal layer; and the external metal layer is connected to a fixed potential.

Abstract: A bridge damage identification method considering uncertainty is used for damage identification based on a convolutional neural network. A domain classifier is added to form a domain adversarial transfer network, a finite element model of a bridge and a time domain acceleration signal of a real structure serve as input, and parameters in a feature extractor are continuously updated in an adversarial process of the domain classifier and the feature extractor, so as to design a brand-new feature extractor, and to achieve a purpose that extracted features are only sensitive to damage. The bridge damage identification method can solve the problem that model-based methods for bridge damage identification are influenced by environment uncertainty or modeling error to generate a difference between the finite element model and the real structure, resulting in reduction in damage identification performance of the method in practical application.

Abstract: The disclosure provides a method for identifying a modal frequency of a beam bridge by considering influence of environmental temperature. The method includes the following steps: installing a sensor on a newly-built beam bridge without damage, measuring a dynamic response of the beam bridge cinder ambient excitation, recording temperature data, processing by a modal parameter identification method to obtain a modal frequency value at the temperature, and starting from a modal frequency corresponding to the temperature, carrying out iterative calculation to obtain the modal frequency at any temperature. The modal frequency value at any temperature is obtained by arranging a small number of sensors and carrying out a small number of tests, so that the influence of the temperature on the modal frequency is quantified, furthermore, the part of environmental influence is eliminated in future damage evaluation of the beam bridge, which allows for a more accurate damage evaluation result.

Abstract: The disclosure provides a method for identifying a modal frequency of a beam bridge by considering influence of environmental temperature. The method includes the following steps: installing a sensor on a newly-built beam bridge without damage, measuring a dynamic response of the nearn bridge cinder ambient excitation, recording temperature data, processing by a modal parameter identification method to obtain a modal frequency value at the temperature, and titarling from a modal frequency corresponding to the temperature, carrying out iterative calculation to obtain the modal frequency at any temperature.