45results about How to "Reduce condition number" patented technology

Method and computer system for logically evaluating a Boolean expression used in a query statement to optimize the query. The Boolean expression refers to an attribute and includes a plurality of conditions. The Boolean expression is received (410) and decomposed (420) into the plurality of conditions. For each condition at least one condition value referring to the attribute is extracted (421) from the condition. The at least one condition value is then inserted (422) into a condition value list in sorted order. A relationship vector of the at least one condition value is initialized (423). Then the relationship vectors of the at least one condition value and of each further condition value that is in the condition list and that is in the value range of the condition are adjusted (424). After having processed all conditions the Boolean expression may be reducing (430) according to each relationship vector.

In illustrative implementations, a time-of-flight camera robustly measures scene depths, despite multipath interference. The camera emits amplitude modulated light. An FPGA sends at least two electrical signals, the first being to control modulation of radiant power of a light source and the second being a reference signal to control modulation of pixel gain in a light sensor. These signals are identical, except for time delays. These signals comprise binary codes that are m-sequences or other broadband codes. The correlation waveform is not sinusoidal. During measurements, only one fundamental modulation frequency is used. One or more computer processors solve a linear system by deconvolution, in order to recover an environmental function. Sparse deconvolution is used if the scene has only a few objects at a finite depth. Another algorithm, such as Wiener deconvolution, is used is the scene has global illumination or a scattering media.

A system to repeat MIMO signals in a network by orthogonally polarizing the signals and maintaining the orthogonal polarization.

The invention discloses a calibration method used for a fully polarimetric microwave radiometer, which accomplishes calibration of the fully polarimetric microwave radiometer through steps as follows: setting initial values of a calibrating device of the fully polarimetric microwave radiometer, confirming a process matrix, confirming a matrix, confirming the condition number of the matrix, and confirming the minimum Kmin(S). The method gives a judgment basis for selecting vectors from a plenty of vectors which can be used in calibrating the fully polarimetric microwave radiometer so as to acquire higher calibrating accuracy. after the minimum condition number optimization is adopted, the obtained fully polarimetric microwave radiometer calibrating matrix has a smaller condition number, the matrix inversion result is enabled to be more stable, the error bound is smaller, and the calibrating accuracy of the fully polarimetric microwave radiometer can be improved. The method disclosed by the invention is characterized in that the error perturbation matrix is applied onto the calibrating inversion matrix of the fully polarimetric microwave radiometer, the calibration source temperature is taken as an optimized parameter, and the minimum condition number is taken as the basis for judging the ill-condition of the calibrating inversion matrix of the fully polarimetric microwave radiometer.

A two-freedom-degree vibration restraining system applied to a high-altitude building robot operating platform comprises a force sensor, two driving rods with the same length, two driven rods with the same length, a horizontal adjusting motor, a magnetic powder clutch, a rotary type magneto-rheological damper, an installing plate and a vertical vibration reducing mechanism. The two-freedom-degree vibration restraining system is characterized in that two installing seat area arranged on the inner surface of the installing plate; each installing seat is connected with the front end of one driving rod through a driving rod controlling shaft, the tail end of each driving rod is connected with the front end of one driven rod, and the tail ends of the two driven rods are connected together; the installing plate, the driving rods and the driven rods form a planar five-connecting-rod mechanism; and the planar five-connecting-rod mechanism can move in a plane perpendicular to the inner surface of the installing plate and has two freedom degrees. The vertical vibration reducing mechanism is arranged on the outer surface of the installing plate.

The invention relates to a three-dimensional reconstruction method in the field of computer vision, and particularly relates to an on-line tracking and dense reconstruction method, an on-line trackingand dense reconstruction system and on-line tracking and dense reconstruction equipment on mobile equipment. The invention aims to realize the on-line dense three-dimensional reconstruction on the mobile equipment. The three-dimensional reconstruction method comprises the following steps: acquiring a current depth image of a frame, calculating a three-dimensional point and a normal vector of eachpixel point under a camera coordinate system, and calculating a depth noise standard deviation and a gradient graph; selecting a point pair capable of providing enough constraint for an ICP algorithmbased on a geometric stability sampling method, and adopting a visual tracking and IMU information fusion method based on an ICP covariance matrix condition number; after calculating the posture of acamera, fusing a depth map into a TSDF model; carrying out light projection on fused volume data at the calculated posture of the camera so as to obtain a surface point cloud. The method is high in robustness and fast in calculation speed. Meanwhile, based on the method, a finally obtained three-dimensional model is reasonable and reliable.