2917results about "Magnetic measurements" patented technology

The invention relates to the technical field of unmanned aerial vehicle application, and discloses a multi-mode electromagnetic field distribution surveying and mapping unmanned aerial vehicle system and an application method thereof. The system comprises a dynamic adjustment module, a multi-band acquisition module, a hybrid positioning module, a three-dimensional modeling module and a multi-modal fusion module. The dynamic adjusting module adjusts the distance between the electromagnetic sensor and the rotor wing according to the rotor wing electromagnetic interference suppression rule; the multi-band acquisition module acquires and processes electromagnetic signals; the hybrid positioning module integrates TDOA and AOA algorithms to position the radiation source; the three-dimensional modeling module generates a three-dimensional electromagnetic field intensity distribution diagram; the multi-modal fusion module fuses the visible light image and the electromagnetic data. The system can also evaluate the risk of the radiation source and plan a flight path. The application method comprises the steps of distance adjustment, data acquisition and processing, radiation source positioning, model construction and the like. According to the method, rotor interference is effectively suppressed, the positioning precision is improved, multi-modal data fusion is realized, and the method has a wide application prospect in the fields of electric power inspection, urban electromagnetic environment evaluation and the like.

The invention discloses a method for improving deformation uniformity of a core wire of an NbTi superconducting wire, and belongs to the technical field of superconducting wire processing. The method comprises the following steps: performing deep hole drilling on an oxygen-free copper ingot rod, then assembling, welding and extruding the oxygen-free copper ingot rod and a single-core rod to obtain a composite rod, and performing multi-pass drawing on the composite rod to obtain the NbTi superconducting wire with high performance, low loss and high N value. The Jc of the prepared NbTi superconducting wire is 2880-3120 A / mm < 2 >, the loss is 450-550 mJ / cm < 3 >, the N value is 70-95, compared with a superconducting wire prepared through a conventional process, the N value is remarkably increased, the loss is remarkably reduced, the critical current density is increased, and the NbTi superconducting wire has wide application prospects in MRI magnets.

Systems and methods for detecting and contouring structures of interest in a 3D image are provided. In an embodiment, a method includes detecting structures of interest from a multi-channel input comprising at least one 3D image and generating a corresponding segmentation map using a first neural network; extracting a plurality of cropped images from the at least one 3D image, each cropped image corresponding to a subregion of the at least one 3D image containing at least one of the detected structures; and estimating contours of the detected structures in the plurality of cropped images and generating corresponding shape representations of the estimated contours using a second neural network. A corresponding system and non-transitory computer-readable medium are also provided.

Disclosed are approaches to non-invasively characterize a tumor or other lesion in a region of interest (ROI) based on various analyses of magnetic resonance imaging (MRI) data. The MRI data may correspond to ultrafast dynamic contrast enhanced MRI (DCE-MRI) and high spatial resolution DCE-MRI scans, and diffusion-weighted MRI (DW-MRI) scans of the ROI. Vasculature metrics may be determined, and tumor-associated blood flow velocity and / or tumor interstitial pressure may be obtained using the vasculature metrics as inputs to a computational fluid dynamics model. A combination of morphological vascular metrics and functional vascular metrics may be used to characterize the tumor. Malignancy, aggressiveness, treatment response, and other features of tumors or other lesions, in the breast or other regions of a patient, may be characterized through disclosed analyses of MRI data.

A computer system that performs quality control (QC) on images associated with diffusion and structural magnetic resonance imaging (MRI) is described. This computer may include: a computation device that executes program instructions; and memory that stores the program instructions. During operation, the computer system may automatically perform a set of validation operations, where, when one or more of the validation operations fails, the images are rejected. Moreover, the set of validation operations may include: performing QC on brain-tissue segmentation; performing QC on diffusion MRI processing; and performing QC on bundles determined from the images using a tractometry technique.

Methods and systems are provided for improving image quality without increasing dose of contrast agent. The method comprises: (a) receiving an input image comprising a pre-contrast image and a full-dose image, the pre-contrast image is a volumetric medical image of a subject acquired without administering contrast agent and the full-dose image is a volumetric image of the subject acquired with standard dose of contrast agent; (b) selecting a path from a plurality of paths to process the input image, the path comprises at least a first model trained to predict a contrast-enhanced image, and a second model trained to denoise an image and wherein the first model and the second model are arranged in a predetermined order to process the input image; generating a predicted image by processing the input image using the path selected in (b), the predicted image has an image quality improved over the input image.

The invention discloses a sensor calibration test system and a calibration test method for UUV intelligent perception, belongs to the technical field of underwater robots, and aims to solve the problems that the capability evaluation of the UUV intelligent perception system is difficult to realize, the credibility, the reliability and the accuracy are poor, and the UUV intelligent perception system cannot be fully matched with the actual application environment and cannot be optimized due to the existing underwater multi-mode comprehensive perception calibration mode. And the development and improvement of the intelligence of the UUV are directly influenced. The sensor calibration test system can simulate various motion modes of the underwater vehicle and the underwater target in navigation, so that a large number of calibration samples are formed, the three-dimensional imaging sonar, the underwater camera and the magnetometer can realize calibration of working parameters based on the underwater acousto-optic magnetic comprehensive beacon arranged on the underwater target, and the calibration precision is improved. After sensor calibration is completed, the system can be used for testing the calibration effect of the sensor, and the number of times and cost of sea test calibration are effectively reduced.

The present application is drawn to a system and method, as well as method for manufacture of a device and system for determining the position and orientation of at least one magnetic field sensor comprising: a rigid structure comprising an array of at least five electromagnetic coils; at least one wire that connects to and powers the electromagnetic coils; wherein the placement and orientation of the electromagnetic coils on the rigid structure are predetermined; wherein the electromagnetic coils, each having a predefined magnetic moment per unit current, are constructed with a printed circuit board (PCB) comprising at least one conductive layer; and wherein the system is configured such that a stray magnetic field emanating from the at least one, as measured at the location of the at least one magnetic field sensor, generates substantially lower magnetic field intensity than that produced by each of the at least five electromagnetic coils.

A system and method for improving image quality of periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) imaging include acquiring a plurality of blades of k-space data of a region of interest in a rotational manner around a center of k-space via a magnetic resonance imaging (MRI) scanner from a coil during a PROPELLER sequence, wherein each blade of the plurality of blades of k-space data includes a plurality of parallel phase encoding lines sampled in a phase encoding order. The system and method also include utilizing a deep learning-based multi-level denoising network to denoise each blade of the plurality of blades in an image domain to generate a plurality of denoised blades, to utilize a PROPELLER reconstruction algorithm to generate a denoised-gridded image from the plurality of denoised blades, and to remove individual-based denoising-induced artifacts from the denoised-gridded image to generate a denoised, artifact-free gridded image.

The invention relates to a soft mesh magnetic sensor for tactile and non-tactile perception. The sensor comprises a neodymium iron boron-organic silicon elastomer magnetic film, an aluminum foil, a PDMS elastomer, a TMR element and a printed circuit board, wherein the TMR element is welded on the printed circuit board, and the PDMS elastomer coats the TMR element and covers the PCB; the PDMS elastomer is covered with an aluminum foil, and a neodymium iron boron-organic silicon elastomer magnetic film is arranged on the aluminum foil; the PDMS elastomer is of a sandwich structure and is composed of an upper thin film, a lower thin film and a middle small cylinder array. The lower film is provided with a strip-shaped groove which is used for wrapping the TMR element. The soft grid magnetic sensor disclosed by the invention has the advantages of high sensitivity, high flexibility and strong multi-mode sensing capability.

The invention discloses a current detection method and system based on a double-ring TMR nested structure, and belongs to the technical field of current detection. The method comprises the following steps: based on a double-ring TMR system of a double-ring TMR nested structure, performing double-ring detection on the current of a to-be-detected wire in a current measurement scene; synchronously acquiring double-ring data obtained by double-ring detection through AD, and performing wavelet denoising on the double-ring data according to the structure data of the double-ring TMR nested structure; and based on a Kalman filtering algorithm, fusing the double-loop data after wavelet denoising to obtain current information of the to-be-measured wire in the current measurement scene. The method not only has outstanding advantages in the aspects of measurement accuracy and anti-interference performance, but also has a wide measurement range and stable linearity performance, and can be widely applied to complex electromagnetic environments with high requirements on current detection accuracy, such as new energy grid connection, electric vehicle charging piles and intelligent power grids.

A dynamic measurement method for spatial magnetic field of transmission lines based on two-dimensional electromagnetic sensor matrix is provided. Data measured by an electromagnetic sensor matrix parallel to the transmission lines is used to calibrate an unmanned aerial vehicle (UAV) flight status, while magnetic field distribution characteristics within a profile of the transmission lines are measured using an electromagnetic sensor matrix perpendicular to the transmission lines, thereby achieving dynamic measurement of the spatial magnetic field of the transmission lines during UAV flight. The method achieves measurement of the magnetic field distribution characteristics within the vertical profile of the transmission lines while ensuring that the UAV flies parallel to the transmission lines. The method solves the problem of dynamically measuring the magnetic field distribution during UAV flight and is significant for accurately identifying transmission lines using magnetic field distribution characteristics.

A magnetic field sensor is provided for sensing a current flowing in a first direction divided in at least two conductor portions separated in a second direction perpendicular to the first direction. It includes at least a first sensing element and second sensing element and at least one integrated magnetic concentrator for sensing the magnetic field at respectively first and second positions in a region between the two conductor portions. The sensing elements are adapted in combination with the concentrator to sense the field with a highest sensitivity in a sensing direction perpendicular to the first direction, wherein the two positions are separated by a predetermined distance in a spacing direction perpendicular to the sensing direction.

An apparatus includes an input unit, a processing unit, and an output unit. The input unit is configured to provide the processing unit with at least one diffusion magnetic resonance imaging dMRI image of a patient's brain. The processing unit is configured to: 1) determine an estimate of an orientation of neurons at each voxel in the dMRI image; 2) determine a plurality of fiber tracts in the at least one dMRI image; 3) select a plurality of voxels along at least one fiber tract of the plurality of fiber tracts; and 4) determine a neurological disease classification.

A magnetoresistive element of the present disclosure includes a multilayer structure made up of at least a fixed magnetization layer, an intermediate layer and a storage layer. A first side wall is formed on a side wall of the multilayer structure. A second side wall is formed on the first side wall. The first side wall is made of an insulating material, for instance SiN or AlOx, that prevents intrusion of hydrogen. The second side wall is made of a hydrogen storage material, for instance titanium.

A flow sensor for sensing fluid flow. The flow sensor includes an exterior, interior, a circuit board, and first and second ports. The first and second ports permit fluid to flow into and out of the interior. A Hall Effect Sensor in the interior detects the number of revolutions of an impeller. An electric coupler interfaces with the flow sensor and a transmitter for communication of the revolutions of the impeller to a controller. The controller determines the rate of fluid flow in a conduit. The controller issues a command signal to a component of a hydraulic system to alter the rate of fluid flow in the conduit.

The invention provides a self-calibration method of a TMR (Tunnel Magnetoresistive) sensor and a TMR sensor array for current measurement, and relates to the technical field of quantum current sensors. According to the method, a double Wheatstone bridge structure is adopted, a to-be-measured bridge is used for measuring a to-be-measured magnetic field, and a reference bridge is used for measuring a known reference magnetic field; the self-calibration of the TMR sensor is realized by calculating the ratio of the output voltages of the two bridges, so that measurement errors caused by environmental factors such as temperature, humidity and mechanical vibration are eliminated; moreover, the invention provides a TMR sensor array for current measurement, the application of the TMR sensor array further enhances the adaptive capacity of the TMR sensor array in a complex environment, and the array is formed by a plurality of TMR sensor units, so that not only can the spatial resolution of measurement be improved, but also the fault-tolerant capability of the system can be improved through redundancy configuration, and the system reliability is improved. The array structure enables the TMR sensor to perform accurate measurement at a plurality of measurement points at the same time to obtain accurate measurement current.

The invention discloses a space magnetic field automatic measurement control system and method, and relates to the technical field of magnetic field measurement. The system comprises a guide rail erected on the inner side of the annular coil and arranged in the axial direction of the annular coil; the measuring device comprises an omnibearing measuring assembly and a supporting part used for supporting the omnibearing measuring assembly. One part of the supporting part is assembled in the guide rail, and the omnibearing measurement assembly comprises a magnetic measurement sensor, a radial driving module, an angular driving module and an axial driving module and is used for measuring magnetic field data of any radial position, any angular direction and any axial position in the annular coil; and the control device is used for respectively controlling the radial driving module, the angular driving module and the axial driving module so as to drive the magnetic measurement sensor to measure magnetic field data at a specified position. According to the invention, precise positioning of a three-dimensional space magnetic field, space omnibearing measurement and space omnibearing automatic control are realized.

A system for detecting proper positioning of an accessory, including an electronic device and an accessory. The electronic device includes a first attachment component, a magnetometer, and a processor. The accessory includes a second attachment component. The second attachment component is configured to be attached to the first attachment component, so that the accessory is fixed through attachment to the electronic device in a first orientation or a second orientation. The magnetometer is further configured to be triggered by a combined magnetic field of the first attachment component and the second attachment component to output the magnetic field intensity information when the accessory is fixed through attachment to the electronic device in the first orientation or the second orientation. The processor indicates whether the accessory is fixed in position based on the magnetic field intensity information.

The invention relates to the technical field of magnetic field distribution detection, in particular to a magnetic field distribution detection method for a medical cyclotron magnet, and the method comprises the steps: equally dividing a to-be-detected medical cyclotron magnet into magnetic field regions; collecting the magnetic field intensity at each moment in each magnetic field area, and dividing all the magnetic field areas into various categories; determining a magnetic field current disturbed value of any magnetic field area at the current moment; acquiring the coil current disturbance of any magnetic field area at the current moment; and combining the magnetic field current disturbed value and the coil current disturbed degree of each magnetic field region to determine the measurement error degree of the magnetic field intensity measured by each magnetic field region, and judging and screening the magnetic field intensity data of each magnetic field region. The magnetic field distribution detection precision of the medical cyclotron magnet is improved.

The invention discloses a neodymium-iron-boron magnet detection system for neodymium-iron-boron waste recovery. The neodymium-iron-boron magnet detection system comprises a detection main body and a detection mechanism. A mounting seat, a first rotating part, a second rotating part and a limiting part are arranged in the detection assembly. After the electromagnetic part is electrified, the electromagnetic part is kept to attract neodymium iron boron waste in the bearing seat, so that the limiting part pulls the upper end of the first rotating part to rotate towards the bearing seat, the lower end of the first rotating part is kept to drive the upper end of the second rotating part to reversely rotate, and the second rotating part applies pressure to the pressure applying part; the pressure applying piece transmits pressure to the pressure sensor. According to the neodymium-iron-boron magnet detection system for neodymium-iron-boron waste recovery, the neodymium-iron-boron waste loaded into the bearing seat is clamped through the mechanical arm and is in automatic butt joint with the detection assembly, automatic operation is achieved, and magnetic force detection is conducted on the neodymium-iron-boron waste. Compared with an existing manual detection mode, personal danger of detection personnel is avoided, meanwhile, the labor intensity is reduced, and the detection precision is improved.

The invention relates to the field of power equipment information detection, and discloses a current harmonic detection device and method, and the device employs a TMR sensor linear array structure, measures a magnetic field generated by a current, outputs a voltage signal, carries out the inversion through a Biot-Savart law to obtain a current value, and carries out the detection of the current harmonic. The influence of external magnetic field noise on a measurement result is reduced by adopting a differential processing mode, finally, current harmonic detection is carried out by utilizing fast Fourier transform added with a Hamming window function, and the fundamental wave of the power frequency current to be measured and the content of each harmonic wave are calculated. According to the current harmonic detection method based on differential processing and Hamming window FFT, interference generated by an external magnetic field and an internal circuit of a sensor is reduced through differential processing, meanwhile, influences of spectrum leakage and the fence effect are reduced through Hamming window FFT, and the harmonic detection performance is further improved.

A system (100) for providing a cardiac signal (SCardiac), is provided. The system includes one or more processors (110) configured to: receive medical image data (120) representing a beating of a heart of a subject; receive initial surrogate cardiac signal data (130) comprising an initial surrogate cardiac signal (SPPG) representing the beating of the heart of the subject, the initial surrogate cardiac signal data (130) being generated contemporaneously with the medical image data (120); analyze the medical image data (120) to provide a reference cardiac signal (SImage) representing the beating of the heart of the subject; determine a correspondence (TD) between the reference cardiac signal (SImage) and the initial surrogate cardiac signal (SPPG); receive subsequent surrogate cardiac signal data (130') comprising a subsequent surrogate cardiac signal (SPPG') representing the beating of the heart of the subject; generate the cardiac signal (SCardiac) based on the subsequent surrogate cardiac signal (SPPG') and the correspondence (TD); and output the cardiac signal (SCardiac).

A system and method for modeling one or more characteristics of a molecule using a quantum device implemented on quantum hardware is disclosed. Through control, via modulation, of coupling strengths between qubits on the quantum device and a comparison to an experimentally-measured nuclear magnetic resonance spectrum, J-coupling values may be deduced. These J-coupling values may then be used to recover the molecular structure of the given molecule. The control of coupling strengths may take place through an iterative process until convergence to the one or more characteristics is reached. In some embodiments, such a process may be implemented as part of a quantum computing service. In such cases, the quantum hardware may be local to the quantum computing service, or may be outsourced to a quantum hardware provider.

A magnetic sensor device includes a magnetic sensor, a die pad, and four leads. The magnetic sensor includes a bridge circuit including a plurality of arms and a plurality of pads electrically connected to the bridge circuit. One of the plurality of arms is provided between one of the plurality of pads and a different one of the plurality of pads in circuit configuration. The magnetic sensor further includes a sub-pad electrically connected between one end and another end of the one arm and also electrically connected to the die pad.

The invention provides a geomagnetic compensation and bias magnetic field generation system and method for cold atom interference. The system comprises a triaxial magnetometer, a triaxial Helmholtz coil, a voltage-controlled current source and an FPGA regulation and control module. The three-axis magnetometer is used for collecting space magnetic field data at a plurality of monitoring positions in the space where the three-axis Helmholtz coil is located in real time; the FPGA regulation and control module is used for calculating control voltage data required by the voltage-controlled current source according to a target magnetic field and any space magnetic field data collected by the three-axis magnetometer in each sampling period, controlling coil current transmitted to the three-axis Helmholtz coil, and outputting the coil current to the three-axis Helmholtz coil. And loop iteration is carried out until the three-axis Helmholtz coil generates a target magnetic field at a plurality of monitoring positions, wherein the target magnetic field is a near-zero magnetic field in the X / Y direction, and the magnetic field intensity in the Z direction is constant and is a non-zero value. The device can respond to the change of the environmental magnetic field in real time, and provides a stable and accurate magnetic field environment for the cold atom interference test on the basis of compensating the influence brought by the geomagnetic field.

The invention discloses a three-dimensional transient magnetic field monitoring system based on sensor array attitude-position combined correction, and the system comprises magnetic field measurement assemblies which are composed of M * N * K three-dimensional sensor arrays and are distributed at equal intervals according to a preset space interval so as to collect transient magnetic field data in real time; the lower computer synchronously collects original data in parallel through the IIC bus and uploads the original data; the upper computer integrates an attitude error correction unit and a cooperative position compensation unit, eliminates the attitude error of the sensor through rotation matrix calculation based on a uniform magnetic field and a gradient magnetic field generated by a Helmholtz coil, and constructs a global optimization model to compensate position deviation. The data processing module adopts cubic spline interpolation to reconstruct continuous magnetic field distribution, and the display module realizes sub-layer visualization and time sequence playback of vector and scalar space-time distribution through a dynamic rendering technology; according to the system, high-precision monitoring of the transient magnetic field is achieved through a hardware parallel architecture and a joint correction algorithm, and the system is suitable for transient magnetic field dynamic analysis in the fields of power equipment, medical imaging and the like.

Systems and methods for fast reconstruction of motion-resolved magnetic resonance images using space-time-coil convolutional networks are disclosed. The system can receive a plurality of k-space data sets. The system can detect a motion signal therefrom. The system can classify the k-space data sets according to states of the motion signals. The system can resolve the k-space data set to Euclidean space images. The system can resolve the Euclidean space images to a combined Euclidian space image. For example, the system can use a convolutional network that exploits spatial, temporal and coil correlations without k-space data consistency to minimize computation time.

A system includes a cylindrical phantom and a conical structure disposed in the phantom. The conical structure is shaped as a frustum and emits Cherenkov radiation when exposed to ionizing radiation. The system can be used for calibration of an MR-Linac system by exposing the system to ionizing radiation. The Cherenkov radiation can be imaged during exposure to ionizing radiation.

A method and system of compensating for body deformation during image acquisition or external beam treatment includes acquiring image data of a body and peak wavelength data from a plurality of fiber Bragg gratings (FBGs) disposed on the body aligned along a predetermined coordinate system on the body, such as a cartesian coordinate system. The method further comprises detecting effective shifts of the Bragg wavelengths of the FBGs caused by body deformation during image acquisition, and controlling the movement of the body through a cavity in a scanning device and controlling the acquisition of the image data or external beam treatment during body deformation based on the effective shifts of the Bragg wavelengths of the FBGs.