128 results about "Detector calibration" patented technology

Calibrating a posture detector for a patient's body involves measuring outputs of one or more sensors disposed in relation to the patient's body while the patient assumes a plurality of positions. A transfer matrix is formed having coefficients corresponding to the measured outputs. The transfer matrix defines a relationship between a coordinate system of the one or more sensors and a coordinate system of the patient's body. The body coordinate system is used as a reference coordinate system for posture detection. Posture, including tilt and/or tilt angle, may be determined based on first and second rotational angles defined in relation to the body coordinate system.

A method for calibrating a digital X-ray detector executed at least in part by a control logic processor. A radiation sensor is disposed along the optical path that extends between a radiation emitter and the digital X-ray detector. A set of radiation beam conditions for X-ray generation is selected and digital image values from the digital X-ray detector are obtained in one or more iterations of providing a threshold signal to radiation control logic, the threshold signal corresponding to a predetermined exposure level, exposing both the digital X-ray detector and the radiation sensor to radiation and terminating the exposure according to a comparison of the threshold signal with a signal from the radiation sensor that indicates an accumulated radiation level, then obtaining the digital image values from the digital X-ray detector. One or more sets of calibration values are generated according to the obtained digital image values.

A method for calibrating multi-headed high sensitivity and high spatial resolution dynamic imaging systems, especially those useful in the acquisition of tomographic images of small animals. The method of the present invention comprises: simultaneously calibrating two or more detectors to the same coordinate system; and functionally correcting for unwanted detector movement due to gantry flexing.

Present embodiments relate to the calibration of detectors having one or more arrays of pixelated detectors. According to an embodiment, a method includes detecting optical outputs generated by a plurality of scintillation crystals of a detector with an array of pixelated detectors, generating, with the array of pixelated detectors, respective signals indicative of the optical outputs, generating, from the respective signals, a unique energy spectrum correlated to each of the plurality of scintillation crystals, grouping subsets of the plurality of scintillation crystals into macrocrystals, determining a representative energy spectrum peak for each macrocrystal based on the respective energy spectra of the scintillation crystals in the macrocrystal, comparing a value of the representative energy spectrum peak for each macrocrystal with a target peak value, and adjusting an operating parameter of at least one pixelated detector in the array of pixelated detectors as a result of the comparison.

The invention provides an online measurement method for the three-dimensional power distribution of a reactor core. The method includes the steps that 1, an existing reactor core is modeled, follow-up analog computation is carried out on the modeled reactor core and an operating history thereof in combination with reactor core state parameters measured online, and theoretical three-dimensional power distribution is obtained; 2, radial correction is carried out on the theoretical three-dimensional power distribution with online measurement data of a reactor core outlet thermocouple in combination with a thermocouple calibration coefficient, and corrected three-dimensional power distribution is obtained; 3, axial correction is carried out on the corrected three-dimensional power distribution with ex-reactor detector data measured in real time online in combination with an ex-reactor detector calibration coefficient, and measured three-dimensional power distribution is obtained. According to the method, the reactor core outlet thermocouple measurement data and the ex-reactor detector measurement data are reasonably utilized, high-precision LPD and DNBR are obtained online, the operating margin of a reactor is directly monitored with early warning given, and the economy and safety of a nuclear power plant are improved.

A method includes determining calibration factors for calibrating photon-counting detectors of a spectral imaging system by combining a heuristic calibration of the photon-counting detectors and an analytical calibration of the photon-counting detectors and generating a set of photon-counting calibration factors based on the combining of the a heuristic calibration and the analytical calibration. The photon-counting calibration factors, when applied to measured energy-resolved data from the photon-counting detectors of a spectral CT scan of a subject or object, mitigate spectral distortion caused by a radiation intensity profile shaper that filters a radiation beam of the spectral CT scan.

The invention relates to a device and a method for demarcating and calibrating a dose monitoring detector in heavy ion beam cancer treatment. The structure of the device is characterized in that a collimator, the dose monitoring detector, a mini ridge-shaped filter, a water tank and a standard ionization chamber are arranged on a beam flux axis in sequence. The standard ionization chamber is arranged inside the water tank. The depth position of an irradiation beam mini spread-out Bragg peak in water is obtained by measuring absorbed dose of the standard ionization chamber at different depth in aqueous medium. At the depth position, the dose monitoring detector is demarcated and calibrated by the standard ionization chamber so as to obtain demarcating and calibrating factors of the measurement of the dose monitoring detector for the mini spread-out Bragg peak cancer treatment beam with a Gauss arrangement. With the demarcating and calibrating factors, the entire process of three-dimensional conformal irradiation therapy with uniform physical absorption dose or uniform biological effective dose in a tumor target volume can be conveniently controlled, the requirements of the treatment of different clinical cases in practical clinical treatment are satisfied, and the treatment efficiency of a treatment device is improved.

A method and system for imaging of a scattering target medium using a modified perturbation formulation of a radiation transport equation where normalized measured values are used to recover a relative difference in absorption and/or scattering properties based on the normalized measured values with respect to a reference medium. The modified perturbation formulation provides enhanced stability, reduces the sensitivity of solution to variations between the target and reference media, produces solutions having physical units and reduces the need for absolute detector calibration. Moreover, the modified perturbation equation lends itself to the detection and imaging of dynamic properties of the scattering medium.

A system (100) includes a stationary gantry (102) and a rotating gantry (104), wherein the rotating gantry is rotatably supported by the stationary gantry. The rotating gantry (104) includes a primary source (110) that emits primary radiation and a detector array (116) having at least one row of detector elements (502) extending along a longitudinal axis. The primary source and the detector array are located opposite each other, across an examination region, and the primary radiation traverses a path (112) between the primary source and the detector array and through an examination region (106) and illuminates the at least one row of detector elements of the detector array, which detects the primary radiation. The system further includes a supplemental source (114), wherein the supplemental source is affixed to a non-rotating portion of the system and emits radiation that traverses a sub-portion of the path and illuminates the at least one row of detector elements of the detector array, which detects the secondary radiation.

The invention provides a method and a device for an oil and gas pipeline deformation detection verification test. The method comprises the following steps that a pipeline to be detected is fixed on a ground support, five lifting jack devices are installed in the middle of the pipeline to be detected, a pipeline inertial measuring device is installed on a pipeline deformation detecting device which is well designed, the pipeline deformation detecting device is pulled to pass through the pipeline to be detected, the pipeline inertial measuring device and an odometer arranged on an odometer wheel of the pipeline deformation detecting device automatically record detection data of the pipeline, the pipeline reaches a predetermined settlement amount of a certain length of a pipeline section by means of the self-weight of the pipeline and the lifting jack devices, the pipeline is pulled to pass through the settled and deformed pipeline, the pipeline settlement deformation and pulling test is repeated, accuracy and effectiveness of data are guaranteed, various kinds of speed are adopted for pulling every time the pipeline is deformed, results of multiple pulling tests are compared, and a pipeline deformation detection device performance verification pulling test is finished. The method and the device provide test data for detector calibration and performance index tests, and improve accuracy and reliability of pipeline integrity evaluation results.

A disposable, single use calibration cartridge for calibrating vaporized fluid detection equipment, such as a breath alcohol tester. The calibration cartridge has a sealed housing having an interior volume, with a saturated working fluid present therein, the saturated working fluid present both in a vapor phase and a liquid phase. The working fluid includes the substance to be detected and a carrier fluid.

The invention relates to a method and device for testing a calibration light source by using an X-ray pulse detector. The device comprises an X-ray pulse generation system and a standard detector calibration system, wherein the X-ray pulse generation system is used for generating X-ray pulse for testing the calibration light source through the standard detector calibration system. The method and device for testing the calibration light source by using the X-ray pulse detector have the advantages of being low in manufacturing cost, exquisite, scientific and reasonable, quantitative in parameter and stable in performance.

The invention discloses a calibration method of a PM2.5 (particulate matter 2.5) detector, characterized by comprising the following steps: (1), placing a PM2.5 detector calibration meter and the PM2.5 detector to be calibrated, into a closed container, and making a gas having initial PM2.5 concentration of 300-500 Mug/m<3>; (2), reading in real time PM2.5 concentration Ci on the PM2.5 detector calibration meter and duty ratio Di on the PM2.5 detector to be calibrated, calculating a particle count according to the duty ratio Di, polynomially fitting with the particle count Pi and the PM2.5 Ci, wherein i=1, 2...n-1; (3) writing a polynomial fitted above into the PM2.5 detector to be calibrated.The calibration method of the PM2.5 detector is simple to operate and low in investment; a calibration equation is made according to the PM2.5 concentration and the duty ratio and written into each PM2.5 detector to be calibrated, equipment runs according to the calibration equitation so that the concentration shown by the detector to be calibrated has good uniformity and accuracy.

A method and apparatus for calibrating a terminal is provided. The apparatus includes a modem; a transmission chain configured to process a signal input from the modem and transmit the processed signal via an antenna; a reception chain configured to process a signal received via the antenna and transmit the processed signal to the modem; and a connector configured to connect an output of the transmission chain and an output of the reception chain via an envelope detector and a switch configured to turn on/off the envelope detector, calibrate a DC offset voltage and I and Q signals of the transmission chain by inputting a one-tone signal of 1 MHz into the transmission channel via the modem in a state where the envelope detector is turned on, and calibrate a second order input intercept point (IIP2) characteristic value by adjusting the signal input into the modem via the reception channel.

The invention relates to a verticality detection scale calibration device for a construction quality detector group, which is used to calibrate the zero position error, display value variability, and display value error of the vertical detection ruler of a construction project quality detector group, including a base, The verticality detection ruler installed with the verticality detection ruler is equipped with a positioning structure and a rotation angle calibration mechanism. Through the overall plan, the calibration of the measurement performance of the verticality detection ruler is realized, providing effective measurement technology guarantee for the quality of construction projects, and improving its The method for calibrating metrological performance fills in the gaps in the calibrating technology of construction quality detector groups.

The invention relates to an oil and gas pipeline traction test method and an oil and gas pipeline traction device. The invention relates to the technical field of pipeline system. According to the invention, a pipeline requiring testing (1) is fixed on a ground supporting rack (3). A detector and a powertrain are connected by using a main traction rope (2) penetrating the pipeline requiring testing (1). A road leading system travels according to a preset speed, and the powertrain travels with a speed maintained the same with that of the road leading system, such that the detector travels through the pipeline requiring testing (1) under traction. The detector automatically records pipeline detection data. When the detector completely passes the pipeline requiring testing (1), the powertrain is stopped, and one time of traction is finished. For ensuring accuracy and validity of data, traction is carried out with various speeds for a plurality of times, such that in-situ traction test is finished. With the method and the device provided by the invention, traction test can be carried out upon pipelines containing defects. Test data can be provided for detector calibration and performance index verification, such that the precision of pipeline integrity evaluation results can be improved.

Disclosed is a method of disposing of radioactive metal waste using melting decontamination, including sorting radioactive metal waste generated in nuclear fuel processing or production facilities by predetermined sorting criteria, and charging sorted metal waste into a melting furnace so as to be melted; adding a impurity remover to the melt of the melting furnace to remove generated slag; pouring the melt having no slag into a mold to form an ingot; subjecting the ingot to gamma spectroscopy using a gamma spectrometer to measure gamma rays of U-235 (185.72 keV, 57.2%) among uranium isotopes, performing detector calibration using a certified reference material and self-absorption correction depending on the density of a medium using MCNP computer code, and calculating total radioactivity of the ingot from the quantified radioactivity and mass of U-235; and efficiently and rapidly determining whether the ingot subjected to radioactivity measurement satisfies a clearance limit.

A nuclear medicine diagnosis apparatus, which rotates a rod-shaped radiation source or a point radiation source while changing the radius thereof and carries out a calibration work, is provided to resolve the following problems. If detector calibration is carried out using a cylindrical phantom whose interior is filled with a ¹⁸F solution, for example, there is a risk that a γ-ray is scattered by the aqueous solution itself inside the cylindrical phantom. Although there is a method for correcting the scattered radiation, the method has a disadvantage that the correction results in poor calibration. Moreover, if a rod-shaped radiation source is rotated inside a tunnel, there is an extremely low risk of causing the above-described scattering because it is rod-shaped. However, this rod-shaped radiation source only rotates on an orbit of a certain radius, resulting in a ring-shaped radiation source having a hollow portion thereinside.

Disclosed is a method of measuring radioactive material of an ingot, in which an ingot having a volume produced by subjecting metal waste generated in nuclear fuel processing or production facilities to melting decontamination undergoes gamma spectroscopy using a NaI detector to measure gamma rays of U-235 (185.72 keV, 57.2%) among uranium isotopes, followed by performing detector calibration using a certified reference material and self-absorption correction depending on the density of a medium using MCNP computer code, and which enables rapid determination of whether the ingot subjected to melting decontamination may be self-disposed of or not.