159results about How to "Reliable calibration" patented technology

Geophysical exploration for oil wells, the source from the vertical seismic profile aspect wave data stack depth domain Corridor profile approach is the use of in situ collection of well spacing VSP data, which will all receive points drilling depth of information and hierarchical data with the depth of information, the use of direct wave VSP data travel through and optimization algorithms are highly accurate anti-layer velocity model, the direct wave to the beginning of the reflected wave in the vicinity of the depth and precision homing imaging, further in-depth domain Corridor section and with the superposition of alternative conventional method leveled in the time domain, with corridors and the superposition method, the results can be superimposed for direct comparison with the drilling and seismic data stratified layer identification. More intuitive, but also made full use of VSP data in the depth of information, make geological formation of the earthquake response and drilling, logging data in depth domain direct contrast, a more intuitive geological layer and the relationship between seismic horizon, thereby enabling layer of identification and calibration more reliable.

In a calibration data input process, a carriage 5 is moved toward an ink sensor 19 to a prescribed position while the ink sensor 19 detecting levels of reflected light. Then the amount of reflected light is read for over a range wider than the width of the carriage 5 including a theoretical detecting position P2. An actual detecting position P1 is found based on the level of reflected light. The difference between the theoretical detecting position P2 and the actual detecting position P1 is calculated and is stored as the calibration value alpha in a first calibration data memory M1. Accordingly, the actual detecting position P1 is set as P2±alpha. The calibration value alpha is used in a calibration process to calibrate the detecting position, so that the level of reflected light can be detected with accuracy.

In a method for calibrating an image capture device that is mounted on a motor vehicle and able to successively capture images of a road area located in front of the vehicle, at least two image objects which correspond to line segments which are straight and substantially parallel to each other in world coordinates are detected in a captured image. With the aid of the image objects, the position of a vanishing point in the captured image is estimated and tracked by a tracking method. In the process, an error is calculated for the position of the vanishing point. As soon as the calculated error decreases to less than a predetermined threshold value, the image capture device is calibrated with reference to the position of the vanishing point associated with the error.

A transformation matrix used for finding actual loads acting on a tire can be reliably calibrated. Using the calibrated transformation matrix, the translation and moment loads exerted on the tire can be calculated with a high degree of accuracy in a multi-component force measuring spindle unit including two multi-component force measuring sensors on locations spaced-apart from each other along the axis direction of a spindle shaft. The calibration method includes a step of measuring loads exerted on the spindle shaft, a calculation step using a measured load vector including the loads obtained in the measurement step and the transformation matrix applied to the measured load vector, to find an actual load vector including actual loads on the tire. Before the calculation step, a calibration step determines the measured load vector under a plurality of linearly independent test conditions and calibrates the transformation matrix based on the determined measured load vector.

The invention discloses a high-precision galvanometer error self-correcting device and a high-precision galvanometer error self-correcting method based on machine vision. The self-correcting device comprises a laser, a marking square head, a focusing lens, an XY-axis movement platform, a camera, an X-axis movement guiderail and a mounting base. The mounting base is provided with an X-axis movement guiderail and a vertical plate. The XY-axis movement platform is mounted on the X-axis movement guiderail. The laser and the camera are mounted on the side surface of the mounting base. The camera is connected with an external image processor. The marking square head is mounted on the side surface of the laser. The focusing lens is mounted on the lower end surface of the marking square head. According to the self-correcting method of the invention, a two-dimensional correction table in practical application of laser marking is obtained through a vision method, namely utilizing the camera and the lens; a laser marking device is corrected by means of the vision method; a unique correction table can be generated for each laser marking device, thereby improving precision and reliability in laser marking and preventing linear distortion and nonlinear distortion in the marking process.

In a method for distortion correction in spiral magnetic resonance imaging, a first MR data set is acquired by scanning raw data space along a spiral trajectory beginning at a first point. A first complex MR image is determined from the first MR data set, which includes first phase information for image points of the first MR image. A second MR data set is acquired by scanning raw data space along the spiral trajectory beginning at a second point that differs from the first point. A second complex MR image is determined from the second MR data set, which includes second phase information for image points of the second MR image. A geometric distortion for image points of the first or second MR image is determined from the first and second phase information, for example with a PLACE method.

The invention discloses a scalable file distribution method used in a distributed system which comprises a management server and at least one host computer and adopts the scalable file distribution method for file distribution. The management server is in charge of scalability management of all host computers of the whole network, can control each host computer to select one address, from an address pool, for downloading a specified scalable file according to the predefined distribution strategy and scalability dispatching algorithm, and conducts installation upgrading for application programs on the host computers. The host computers inform the management server of the access addresses of locally downloaded scalable files, and the management server allows other host computers to access the addresses to download the scalable files. Each host computer can not only download the scalable files from other host computers but also serve as a download server to provide download service for other host computers. The scalable file distribution method can be used by any distributed systems including a cloud system, effectively prevent the management server from bottlenecks, makes the best of resource capabilities of all servers in the whole network, and can quickly achieve file distribution in a controllable manner.

An ion resonance condition is corrected accurately in an ion trapping device. Measurements are repeated by alternately applying and not applying a resonance frequency voltage while spectral data is obtained continuously. Data obtained in the absence of the resonance frequency voltage is used as reference data to correct the set data of a resonance condition. As a result, calibration can be made while taking into consideration the variations in the amount of ions that are introduced into the ion trap.

Yellow reference patterns, magenta reference patterns and cyan reference patterns are printed as a gradation scale of each color on a leading end of a long web of color heat sensitive recording paper in the factory. Respective density grades of each color are indicated by density numbers. Yellow, magenta and cyan calibration patterns are printed by a color thermal printer to calibrate, at a constant density on the recording paper adjacently to the reference patterns of the corresponding colors. The user compares the calibration pattern of each color to the reference patterns of the corresponding color, to determine the density grade of the actual density of the calibration pattern. By entering the density number of the determined density grade for each color, the color thermal printer automatically corrects three color densities on the basis of the entered density numbers.

An optical position-measuring device is arranged for recording the relative position of a scanning unit and a scale movable to it in at least one measuring direction. The scale is configured as a combined unit which includes at least one reflector element as well as a measuring graduation. A light source and one or more detector elements are assigned to the scanning unit. The scanning unit includes splitting device(s) which split the beam of rays, emitted by the light source, into at least two partial beams of rays in the measuring direction, which after being split, propagate in the direction of the scale.

An image forming apparatus that can reliably correct for skew of a sheet being conveyed. The amount of skew of the sheet is detected, and the amount of toner used for an image formed on a first surface of the sheet is determined. When the sheet with the image formed on the first surface thereof is conveyed so as to form an image on a second surface of the sheet, a skew correction roller unit is controlled so as to correct for the skew of the sheet based on the detected amount of skew and the determined amount of toner used.

An error identification method includes a tool sensor position acquisition stage, a reference block position acquisition stage, a relative position calculation stage, a reference tool position acquisition stage, a position measurement sensor measurement stage, a length compensation value calculation stage, a diameter compensation value acquisition stage, a position measurement stage, a position compensation stage, and a geometric error identification stage. The diameter compensation value acquisition stage acquires a radial direction compensation value of the position measurement sensor with the measured jig. The position measurement stage indexes the rotation axis to a plurality of any given angles and measures respective positions of the measured jig. The position compensation stage compensates the position measurement value at the position measurement stage using the length direction compensation value and the radial direction compensation value. The geometric error identification stage identifies the geometric error from the plurality of position measurement values.

An apparatus of correcting an offset for a differential amplifier which compensates a direct current (DC) offset voltage in a differential analog signal amplifier using a resistive feedback structure to minimize a deviation and a method thereof are provided. The apparatus includes a differential amplifier that is configured to amplify a common DC voltage input via a first resistor and a second resistor with a predetermined amplification factor to output the amplified voltage. A controller is configured to compare voltages output from both output terminals of the differential amplifier to determine whether to generate an offset. In addition, the offset is corrected using a switching unit coupled in parallel to an input terminal of the differential amplifier in response to detecting a generated offset. The controller is also configured to adjust an asymmetric property of the input terminal of the differential amplifier to correct the generated offset.

A method for calibrating a pressure sensor includes connecting the pressure sensor to first and second fluid storage vessels; providing an initial fluid pressure at the pressure sensor and at the fluid storage vessels; and carrying out a pressure measurement of the initial fluid pressure at a time t₀. The method then disconnects the second fluid storage vessel from the pressure sensor and the first fluid storage vessel; provides a first fluid pressure at the second fluid storage vessel; and carries out a pressure measurement of the first fluid pressure at a time t₁. The method then connects the second fluid storage vessel with the pressure sensor and the first fluid storage vessel, so that a second fluid pressure between the initial and first fluid pressures is provided at the pressure sensor; and carries out a pressure measurement of the second fluid pressure at a time t₂.