47 results about "Separable denominator" patented technology

The invention provides a method and a device for drawing a molecular formula annotation on an electronic map. The method comprises the following steps that: obtaining a position coordinate which needsto draw the annotation on the electronic map, and converting the position coordinate into a pixel coordinate (x,y); independently taking two attribute field values of which the annotations need to bedisplayed as the numerator and the denominator of the molecular formula, measuring the length of the numerator character and the denominator character in the molecular formula, and converting into ascreen pixel distance; measuring the height of the denominator character in the molecular formula, and converting into a screen pixel distance; calculating the length of a fraction line; calculating the drawing positions of the numerator character, the fraction line and the denominator character; and drawing the numerator, the denominator and the fraction line to the corresponding positions of theelectronic map to form an integral molecular formula annotation. By use of the method, two attribute field values can be displayed through one modular formula annotation so as to be more visually andattractively displayed, annotation display is clear, and a drawing method is integrally simple and is unlikely to make mistakes.

The invention discloses a method for locating faults in a double-terminal direct current distribution network based on current adaptive control, characterized in that the method for locating faults includes the following steps: step S1: constructing a model of a double-terminal flexible direct current distribution network; step S2: fault detection and countermeasures; step S3: system sampling; step S4: obtaining a calculation formula; step S5: calculating the final fault distance. The fault location method of the present invention uses the double-end method to eliminate the transition resistance, has a high resistance to the interference of the transition resistance, adopts the fault current adaptive control, and extracts the actual fault current at the moment of switching the control mode as the peak value of the reference signal, and the zero-crossing point of the reference signal is still It can greatly reduce the adjustment time of PI and improve the accuracy of active current control. The numerator and denominator univariate linear regression analysis of the traditional double-ended fault location method can effectively reduce the error between different sampling points and greatly improve the fault location accuracy. .

The invention discloses a video PRNU noise extraction method and a camera source detection method, belonging to the field of camera source detection, and the technical problem to be solved is that the PRNU noise in a stable video segment cannot be reliably estimated and matched. The extraction method includes: taking video frames with the same geometric transformation as the same group; replacing the numerator in the traditional video PRNU noise calculation formula with the sum of the product of each group of residual noise and video frame, and replacing the denominator in the traditional video PRNU noise calculation formula For the video frames from the same group, the video PRNU noise calculated for each group of video frames is accumulated. The detection method includes: expanding the traditional PRNU noise calculation formula based on the maximum likelihood estimation method through the above method; performing overlapping and striping on the PRNU noise, and matching the reference PRNU noise and the test PRNU noise; judging the test video according to the single peak value Is it from the reference phone.

The invention discloses a QMF group design method based on the all-pass filter hybrid iteration technology. The method includes determining the number of filters, order number, cut-off frequency and ideal phase of each filter according to the design objective. The actual phase and the actual phase difference of the filter are then calculated to obtain the actual phase difference of the overall distortion function. The linearization of the denominator and numerator of the objective function is completed through LSK processing and alternate iteration methods, and then the filter coefficients are obtained through the CVX toolkit. Finally, judge whether the result meets the design requirements, and if not, correct the weighted value and re-iterate. This method reduces the complexity and difficulty of solving the formulas in the design process through mathematical processing, and combines different means of nonlinear processing methods to control the overall phase error and stop band amplitude error of the filter bank within the required range.