43results about How to "Reduce the number of calibrations" patented technology

The invention belongs to the technical field of non-invasive blood pressure detection and particularly relates to a non-invasive blood pressure continuous detection device and a non-invasive blood pressure continuous detection method. The non-invasive blood pressure continuous detection device comprises a volume pulse wave image detection module, an electrocardiogram detection module and a signal analysis processing module; the volume pulse wave image detection module is used for acquiring a direct current component and an alternate current component in a blood volume pulse wave; the electrocardiogram detection module is used for acquiring an electrocardiosignal of a human body; and the signal analysis processing module is used for acquiring PWV (Pulse Wave Velocity) information according to the electrocardiosignal acquired by the electrocardiogram detection module and the alternate current component detected by the volume pulse wave image detection module, acquiring blood vessel radius information according to the alternate current component and the direct current component and acquiring continuous blood pressure information according to the PWV information and the blood vessel radius information. Due to implementation of the non-invasive blood pressure continuous detection device and the non-invasive blood pressure continuous detection method which are disclosed by the invention, influence of variation of the blood vessel radius on the blood pressure in the long-term non-invasive blood pressure measurement process is removed, accuracy of long-term detection is improved, and times of continuously calibrating the blood pressure are reduced.

The invention discloses a bridge construction deformation monitoring device, which belongs to the technical field of bridge construction and includes a detection device, a laser monitoring device, an upper support platform, a lower support platform, an adjustment mechanism, a liquid level control mechanism, a lifting mechanism, a laser detection mechanism and a laser Alignment body. The present invention provides a bridge construction deformation monitoring device, selects a plurality of datum planes, detects the change of the detection device to which each datum plane belongs through laser alignment, selects the datum plane with the smallest variation range, and divides the datum planes into There are multiple areas, and a liquid level control mechanism is buried in each area. Through the principle of liquid communication, the liquid level control mechanism pushes the monitoring equipment to adjust its position accordingly when multiple areas change, so that the monitoring equipment maintains a state with the smallest change. The monitoring equipment passes Automatic straightening by gravity straightening method and laser alignment method make it easier to install between multiple devices and avoid excessive errors.

The invention discloses a large-area optical profilometer calibration method based on a double-wavefront interference fringe array; it comprises acquiring a double-wavefront interference fringe array image modulated by the optical profile of an object to be measured, and constructing a calibration model; Use the calibration plate to calibrate multiple sections, and determine the calibration parameters; draw the change curve according to the calibration parameters, and construct a fitting function for fitting processing; sequentially substitute the moving distance of adjacent interference fringes perpendicular to the fringe direction into The fitting function obtains the calibration parameters of each interference fringe; the real shape of each section is restored according to the image data of the interference fringes and the calibration parameters, and the calibration of the optical profile measurement of the object to be measured is realized. The present invention constructs a calibration model of a double-wavefront interference fringe array image, and uses a fitting method to determine the calibration parameters in the calibration model of each interference fringe, greatly reducing the number of calibrations, and realizing large-area optical profile measurement simply and efficiently calibration.

The invention relates to a hand-eye calibration method, in particular to a hand-eye calibration method for workpieces. According to two-time hand-eye calibration data of layers separated by multiple layers, the workpiece position and posture coordinates of all intermediate layers are subjected to automatic interpolation calculation. The problem that layer-by-layer calibration is needed due to space relative position change is effectively solved, the number of calibration times is decreased, the time is saved, the labor work intensity is reduced, and the grasping precision is improved.

The embodiment of the invention discloses a calibration method and device for a DCOC. The method can comprise the following steps: corresponding to the radio frequency receiver in a calibration state,detecting the direct current offset of the radio frequency receiver at each gain level at the digital output end of the radio frequency receiver; Determining calibration data of the radio frequency receiver at each gain level according to the direct current offset of the radio frequency receiver at each gain level; Determining a target gain level of a current gain value corresponding to the working state of the radio frequency receiver; Determining calibration data corresponding to the target gain value in the calibration data of the radio frequency receiver under each gain level; And generating a corresponding direct current compensation value from the calibration data corresponding to the target gain value, and compensating through an ADC input end of the radio frequency receiver according to the direct current compensation value.

The invention relates to an engine spray simulation calibration method and system. The engine spray simulation calibration method comprises the following steps that a current oil beam actual drop point coordinate is obtained according to spray oil beam simulation model and a relevant parameter of a preset injector; the relevant parameter of the preset injector comprises a current input oil beam drop point coordinate; a drop point error of this round is obtained according to a target oil beam design drop point coordinate and the current oil beam actual drop point coordinate; when the drop pointerror of this round is not in a preset error range, the sum of drop point errors of all previous rounds, the drop point error of this round and the target oil beam design drop point coordinate is obtained, and the input oil beam drop point coordinate used for calibrating the next round is obtained; and when the drop point error is not in the preset error range, the oil beam actual drop point coordinate corresponding to the drop point error in the preset error range is obtained, and completion of engine spray simulation calibration is conformed.

The present invention screens out a homocysteine ​​methyltransferase mutant by error-prone PCR and site-directed mutation, which contains one or two amino acids at D53, D283, L252, and Q219 on the basis of wild-type HMT. The above amino acid mutations. The mutant doubled its activity and improved its stability. The present invention also discloses the nucleic acid encoding the homocysteine ​​methyltransferase mutant, the expression vector comprising the nucleic acid, the host cell comprising the expression vector, and the homocysteine-S-A A reagent of at least one of a base transferase mutant, a nucleic acid, an expression vector, and a host cell.

The invention discloses a method for calibrating a cross-shaped hot-wire anemometer, which includes: measuring the angle θ between the cross-shaped hot-wire probe and the airflow direction; starting data collection; fitting curved surfaces, and calculating the cooling constant k of the cross-shaped hot-wire probe , the calibration constants A, B and n; the effective cooling rate of the cross-type hot wire probe U e calculation steps. It has the advantages of greatly improving the quality of test data and saving test time.

The invention discloses a linear calibration system based on a camera coordinate system and a method thereof. The system comprises a coordinate system construction module, an image point position offset estimation module, a focal length calculation module, a camera parameter calculation module and a target point position calculation module. And the coordinate system construction module and the image point position offset estimation module are used for obtaining a theoretical estimation of an imaging point position offset volume. An objective function is established based on an coordinate errorbetween imaging point actual coordinates and imaging point theoretical estimation coordinates. Partial derivatives of the objective function are solved about intrinsic parameters of the camera, and acamera intrinsic parameter linear algorithm is given out. According to the method, the problem of coupling between camera intrinsic parameter and external parameter calculation is solved, a camera calibration parameter calculation model is simplified, and the precision of a camera calibration result is improved.

The invention relates to a cable testing bus and a switching matrix circuit. The cable testing bus consists of a differential line pair and a double-pole-double-throw switch; the moving contact and the normally closed contact of the switch are connected on the differential line pair; the switching matrix circuit takes the cable testing bus as a main signal path, and comprises two transformers andfour cable testing buses; and the coaxial end of the transformer is connected with the port of a testing apparatus, and the symmetrical end of the transformer is connected with the cable testing bus.The switching matrix circuit is characterized by cutting material cost, minimizing odds of testing equipment failure and reducing workload of nonstop calibration. The cable testing bus has the advantages that normal isolation from objective can be realized and the length of the cable testing bus can be controlled on the spot. Furthermore, the cable testing bus has sufficient bandwidth and constant characteristic resistance, and keeps working in matching condition, thereby ensuring measurement accuracy.

The invention provides a PWTT-based dynamic continuous blood pressure measurement watch, which belongs to the technical field of non-invasive continuous blood pressure measurement. The present invention flexibly screens PWTT data, and obtains PWV through PWTT, arm length, and the average distance from the shoulder to the heart of a normal person, so that the final calculation of PWV has higher precision. At the same time, when calculating blood pressure based on PWTT, not only the direct correlation between the two is considered It also considers the relationship between high pressure, pulse pressure, heart rate and blood pressure, by calculating the autocorrelation coefficient, regression coefficient and regression constant between each group of data, and finally calculates the blood pressure value according to the calculated parameter regression equation, the result is more accurate, In addition, during this process, the real-time collected data and calibration data will participate in data screening and calculation of subsequent regression coefficients, etc., and the real-time collected data will be added to the calibration area for new measurements. By continuously optimizing the calibration area, the Blood pressure measurements are more accurate.