4results about How to "Big change" patented technology

The invention discloses a software defect prediction feature selection method based on an improved whale optimization algorithm, and the method comprises the following steps: obtaining traditional features of a single file in a folder where a software source code to be predicted is located, and forming a data set; preprocessing the data set of the to-be-predicted software; dividing the preprocessed data set of the prediction software into a test set and a training set according to a proportion; based on the training set data, an improved whale optimization algorithm is adopted for training, and traditional features corresponding to the to-be-predicted software source code file are screened out; and adopting the screened traditional features to predict the number of defects of the source code of the software based on the test set data. According to the method, the data dimension can be effectively reduced, the calculation complexity is reduced, and the problem of dimension disasters caused by redundant features is avoided, so that the generalization ability and the prediction precision of the model are improved.

The application discloses a method for analyzing inter-turn short circuit fault characteristics of a parallel winding permanent magnet synchronous motor, and comprises the following steps: step one, obtaining the parameter relationship of each branch circuit according to the equivalent circuit of the PCW PMSM under the ITSC; step two, selecting the negative sequence voltage component, the three-order harmonic of the phase current and the circulating current as the fault characteristics and constructing the model of the negative sequence voltage, the three-order harmonic of the phase current and the circulating current; step three, analyzing the influence of the parallel winding on the ITSC characteristics according to the model of the negative sequence voltage component, the three-order harmonic of the phase current and the circulating current, then analyzing the influence of the fault mode on the phase current and phase voltage characteristics and the influence of the short circuit position on the phase current and phase voltage characteristics according to the model of the negative sequence voltage and the three-order harmonic of the phase current, and finally analyzing the circulating current fault characteristics according to the model of the circulating current. The method has the beneficial effects that the winding configuration, the fault mode and the short circuit position of the ITSC characteristics can be accurately detected, and the evaluation accuracy of the ITSC is improved.

This application discloses a detection circuit and detection method for a capacitive MEMS sensor, comprising: a reference voltage boosting module connected to the driving terminal of the capacitive MEMS sensor to provide an excitation voltage, providing a reference voltage to the driving terminal in a first stage, boosting the reference voltage to the driving terminal to a first voltage amplitude in a second stage, and switching the excitation voltage of the driving terminal from the first voltage amplitude to a predetermined low level in a third stage; a common-mode cancellation module including a signal input terminal and an excitation terminal, the signal input terminal being connected to the output terminal of the capacitive MEMS sensor, and the excitation terminal receiving an excitation signal to drive the common-mode cancellation module to reduce common-mode fluctuations in the detection signal at the output terminal; and an operational amplifier module amplifying the detection signal with reduced common-mode fluctuations to generate an output signal. This application employs staged timing control of the reference voltage boosting module to generate excitation for the capacitive MEMS sensor, effectively reducing noise in the detection circuit.

The present invention discloses an optical path changing device and an optical interference system, comprising a driving motor, a turntable mechanism, a reference arm, a first collimator and a first reflector; the reference arm can rotate integrally with the turntable mechanism; the reference arm comprises a triangular reflector for changing the optical path, and the triangular reflector comprises a first reflective lens, a second reflective lens and a third reflective lens intersecting in pairs. The optical path changing device and the optical interference system disclosed by the present invention can realize continuous change of the optical path, with high efficiency and convenient operation.