14714 results about "Nuclear physics" patented technology

A system includes a magnetic stimulation coil; and a machine vision navigation device comprising a camera configured to capture successive still images and / or to stream video indicating position of the magnetic stimulation coil. The machine vision navigation device is configured to determine, based on the successive still images and / or the video, the position of the magnetic stimulation coil relative to a target treatment area of a patient, and cause, based on the position of the magnetic stimulation coil relative to the target treatment area of the patient, display of an indication of the position of the magnetic stimulation coil relative to the target treatment area of the patient.

A system for administering transcranial magnetic stimulation in which two or more coils are applied to the patient's body. The coils each may emit a magnetic field which when positioned in one or more configurations result in field overlapping. Magnetic field overlap achieves therapeutic effects otherwise difficult, or impossible, to achieve from traditional single coil TMS devices.

A driving method of a transcranial magnetic stimulation 3D coil device is disclosed, which includes: determining first and second signal peaks corresponding to a specified rotating magnetic field direction, in which the first and second signal peaks respectively correspond to first and second coils in multiple coils; providing a first pulse current having the first signal peak to the first coil, in which the first pulse current signal stimulates the first coil to provide a first magnetic field; providing a second pulse current signal having a second signal peak to the second coil, in which the second pulse current signal stimulates the second coil to provide a second magnetic field, in which the first magnetic field and the second magnetic field form a rotating magnetic field having the specified rotating magnetic field direction.

Systems, methods, and computer programs disclosed herein relate to training and using a machine learning model to generate contrast-enhanced magnetic resonance images.

A nuclear fusion reaction device, system and method. The outer wall of a vacuum chamber (301) in the nuclear fusion reaction device (30) comprises an inner ring surface (M1) and an outer ring surface (M2) which are connected to each other; the outer ring surface (M2) surrounds the inner ring surface (M1); the inner ring surface (M1) protrudes toward the central axis of the vacuum chamber (301); the vacuum chamber (301) surrounds a plurality of first coils (302); at least some of the plurality of first coils (302) extend in the circumferential direction of the inner ring surface (M1) and are sequentially arranged in the axial direction of the vacuum chamber (301); a plurality of second coils (303) surround the vacuum chamber (301), extend in the circumferential direction of the outer ring surface (M2), and are sequentially arranged in the axial direction of the vacuum chamber (301); a plurality of third coils (304) all surround the vacuum chamber (301) and are sequentially arranged in the circumferential direction of the vacuum chamber (301); and the plurality of first coils (302), the plurality of second coils (303), and the plurality of third coils (304) are used for generating a magnetic field, such that plasma rings with negative triangular deformation are generated in the vacuum chamber (301), and a fusion reaction occurs.

The present disclosure provides a magnetic resonance signal processing device. The device may include: a signal receiving unit configured to obtain a received magnetic resonance signal, wherein at least part of the magnetic resonance signal is generated by exciting one or more specific nuclides; an analog-to-digital converter configured to perform an analog-to-digital conversion on the magnetic resonance signal; and a control unit configured to obtain a digital output signal of the magnetic resonance signal by processing the magnetic resonance signal after the analog-to-digital conversion.

MRI interference with a co-existing ultrasound system may be reduced or avoided by carrying out RF-sensitive operations of the treatment system only when gradient field activity of the MRI system is suppressed.

An infusion system may include a radioisotope generator that generates a radioactive eluate via elution, a beta detector, a gamma detector, and a controller. The beta detector and the gamma detector may be positioned to measure beta emissions and gamma emissions, respectively, emitted from the radioactive eluate. In some examples, the controller is configured to calibrate the infusion system using the gamma detector. For example, the controller may generate a radioactive eluate and measure the activity of the radioactive eluate using both the beta detector and the gamma detector. The high accuracy of the activity measured by the gamma detector may be used to calibrate the infusion system. In subsequent use, the infusion system calibrated using the gamma detector may adjust measurements made to monitor and / or control patient infusion procedures.

The invention discloses an imaging method and system based on cosmic ray muon transmission, which are applied to a control mechanism, and the control mechanism is electrically connected with at least one detection module. The imaging method based on cosmic ray muon transmission comprises the steps that the response state of at least one detection module is obtained, the detection module comprises a plurality of sensor units, and the sensor units are arranged in a string shape. And preprocessing the response state to obtain muon flux in unit area, unit time and unit solid angle. Based on the topographic data, the landform data and the muon flux, the density distribution in the muon ray irradiation range is reversely deduced through a preset algorithm. And performing visual imaging based on a density distribution result. According to the method, the working efficiency of muon geological imaging is improved, the system complexity is reduced, the adaptability in a narrow working environment is remarkably enhanced, and an efficient and convenient solution is provided for the fields of geological exploration, engineering detection and the like.

The present invention discloses an electrophysiological catheter having a distal microelectrode assembly, the distal microelectrode assembly having a covered ridge carrying a plurality of microelectrodes. The microelectrode assembly includes a first ridge radiating away from the longitudinal axis and a second ridge adjacent to the first ridge and radiating away from the longitudinal axis, the first ridge having a plurality of first microelectrodes disposed thereon. The second ridge has a plurality of second microelectrodes disposed thereon such that a first virtual circle intersecting one of the plurality of first microelectrodes does not intersect any of the second microelectrodes.

The invention relates to the field of medical equipment, and provides a compact multi-chamber proton treatment system based on a shared beam line, and the system comprises a fixed beam transmission line which is used for guiding the movement direction of a proton beam into a vertical direction; the rotating beam transmission line is used for guiding the movement direction of the proton beam into the horizontal direction; one end of the fixed beam transmission line is connected with the proton cyclotron, the other end of the fixed beam transmission line is connected with one end of the rotary beam transmission line, and the other end of the rotary beam transmission line is in butt joint with a plurality of treatment rooms; the rotating beam transmission line rotates around a central axis extending in the vertical direction. According to the invention, the proton beam can be safely, efficiently and accurately transmitted to each treatment room, and a fixed beam transmission system and a rotating rack do not need to be independently arranged for each treatment room, so that the beam control assembly and the system occupied area of the multi-room particle treatment device are minimized, and the number of treated patients can be remarkably increased.

The invention discloses a beam current testing device for accelerator beam current debugging, which comprises an integrated short-distance testing device without a focusing or deflecting magnet, and is characterized in that the testing device comprises a vacuum chamber, and at least two beam current position detectors are integrated on the vacuum chamber along the beam current ejection direction of an accelerator; the two beam position detectors connected with the vacuum chamber are symmetrically arranged on the two sides of the vacuum chamber, and the center distance is adjustable; the vacuum pipeline where the beam position detector is located is coaxially provided with a flow intensity measuring device and a beam garbage target, and the flow intensity measuring device is provided with an insulation sealing structure for preventing generation of mirror current; and a vacuumizing device is also integrated on the vacuum chamber. The testing device is not provided with any magnet, does not focus or deflect the beam current, is simple in structure, achieves the measurement of the beam current intensity, beam current energy and beam spot size through the simplest structure, is small in installation space, meets the requirements of ACCT current intensity measurement for isolating mirror current, and can be flexibly installed according to the needs.

The invention relates to the technical field of medical cyclotrons, in particular to a medical cyclotron magnetic field intensity adjusting method based on temperature compensation, and the method comprises the following steps: in the process of adjusting the magnetic field intensity of a main magnet based on temperature information, obtaining a temperature variation threshold: collecting the temperature on the surface of the main magnet in real time; determining a temperature difference coefficient, a temperature anomalous coefficient, a temperature abnormal coefficient and a trend approximate value of each acquisition moment; comprehensively analyzing the temperature values acquired by all the sensors, and determining the temperature difference degree and difference factor of each sensor at each acquisition moment; determining the avoiding adjustment value of each sensor at each acquisition moment; and acquiring a temperature variation threshold value at each acquisition moment. The invention aims to solve the problem that the magnetic field intensity of the cyclotron cannot be adjusted according to the actual environment temperature, so that the beam stability and the beam extraction efficiency in the operation process of the medical cyclotron are improved.

The invention discloses an MRI (Magnetic Resonance Imaging) image segmentation method based on WKA-Unet. The MRI image segmentation method comprises the following steps: 1) data preprocessing; 2) constructing a WKA-Unet network; and 3) testing. According to the technical scheme, on the basis of a U-Net network structure, an MRI image segmentation model is improved; a traditional Unet network is combined with a self-designed WKA module, multi-scale features are fully captured by using wavelet transform convolution and KAN convolution, and the loss of traditional Unet global information is relieved; an attention mechanism is introduced to pay attention to key parts, and redundant information is removed; according to the technical scheme, the network is trained more flexibly and accurately, a more accurate segmentation result is obtained, the segmentation precision is high, and the model structure is efficient and stable.

The utility model relates to the technical field of electron beam transmission, in particular to a magnet system. Comprising a first shaping unit and a second shaping unit, and the first shaping unit comprises first quadrupole iron tightly attached to an outlet of the accelerating tube and first octupole iron arranged at the focus position of the first quadrupole iron; the second shaping unit comprises second quadrupole iron and second octupole iron, the second quadrupole iron and the first octupole iron meet a first preset distance, the second octupole iron is arranged at the focus position of the second quadrupole iron, and the second shaping unit and the radiation field area meet a second preset distance; the inner diameter of the first octupole iron and the inner diameter of the second octupole iron are both larger than or equal to the maximum size of an electron beam group. Therefore, the quadrupole iron and the octupole iron are utilized to form the shaping unit which is homogenized in one direction, so that the problems that in the prior art, in the electron beam transmission process, a large amount of dose is lost, the size of a radiation field is limited, and the radiation field cannot be adjusted at will are solved; therefore, the electron beam bunch generated by the linear accelerator can be expanded and homogenized in a short distance.

A positron emission tomography (PET) scanner includes a plurality of gamma radiation detector modules arranged to form a detector ring. Each detector module includes an array of scintillator detectors. Each scintillator detector comprises a monolithic scintillation crystal and a plurality of photodetector arrays, such as silicon photomultipliers (SiPMs). A photodetector array is positioned on at least two nonparallel faces of each scintillation crystal. In some examples, a photodetector array is positioned on each of three orthogonal faces of each scintillation crystal.

The invention relates to a magnetic resonance system frequency calibration method and device, equipment, a storage medium and a product. The method comprises the following steps: carrying out first scanning on a to-be-scanned object by utilizing a selective water excitation sequence to obtain a first echo signal; performing second scanning on the to-be-scanned object by using the selective water excitation sequence to obtain a second echo signal; according to the first echo signal and the second echo signal, the frequency drift amount of the magnetic resonance system in the current time period is calculated; and calibrating the frequency of the radio frequency coil of the magnetic resonance system according to the frequency drift amount of the magnetic resonance system in the current time period. According to the method and the device, the system frequency is calibrated by the selective water excitation sequence, and the selective water excitation sequence only excites the water signal and does not excite other types of signals including metabolite signals; therefore, the stability of the metabolite signal is not influenced, the accuracy of the target metabolite signal is not influenced, and the quality of the spectrum image is not influenced.

The present disclosure discloses an integrated rapid treatment system for nuclear medical radioactive wastewater and an application method thereof. This system includes a wastewater collection unit; a pretreatment unit; a deep purification unit; a solid decay unit; a buffer unit; an online monitoring unit; and a control unit, wherein the online monitoring unit includes a radioactivity level detection module for detecting total α and total β radioactivity concentrations of inlet and outlet water of a medium in each unit, and a real-time monitoring module for treatment process parameters. The present disclosure discloses an integrated rapid treatment system for nuclear medical radioactive wastewater and an application method thereof, which can efficiently and quickly purify multi-nuclide organic low-level wastewater produced by a nuclear medical process, and realize rapid online monitoring and automatic control at the same time.

The invention relates to the technical field of analysis and detection, in particular to a method for identifying free nucleic acid and nucleic acid wrapped by a carrier based on nuclear magnetic resonance phosphorus spectrums.The method comprises the following steps that 1, the free nucleic acid serves as a contrast, nuclear magnetic resonance phosphorus spectrum detection is conducted, and a nuclear magnetic phosphorus spectrogram of the free nucleic acid is obtained; (2) taking the nucleic acid combined with the carrier as an experimental group, and performing nuclear magnetic resonance phosphorus spectrum detection under the same condition to obtain a phosphorus spectrogram of the experimental group; and (3) comparing the characteristic changes of peak positions, peak shapes, peak heights, peak areas and the like of the experimental group and the control group to identify the free nucleic acid and the nucleic acid wrapped by the carrier. The method has good accuracy, repeatability and stability, can be used for nondestructive testing, and is suitable for analyzing sensitive samples. The method can be used for detecting the binding condition of a carrier and nucleic acid in a nucleic acid drug, predicting the encapsulation efficiency and release rate of the nucleic acid drug, and providing an important analysis tool for opening, production and quality control of the nucleic acid drug.

A method comprises: providing FIB and CPB columns with FIB and CPB optical axes coinciding at a wafer surface; in the coincidence arrangement, removing a cross section surface layer of a measurement site of a wafer using the FIB column to make a new cross section accessible for imaging; reducing a working distance between the CPB imaging column and the wafer surface in a direction along the axis of the CPB imaging column; imaging the new cross section at the measurement site of the wafer with the CPB imaging column at the reduced working distance and thus not in the coincidence arrangement; and increasing the working distance between the CPB imaging column and the wafer surface in the direction along the axis of the CPB imaging column until the coincidence arrangement is reached.

Disclosed in the present invention is a radioactive source-based assistance apparatus for inspecting a butt weld of a small-diameter pipe, comprising: an adjusting module, comprising a first adjusting rod, an adjusting block being slidably connected to the outer surface of the first adjusting rod, a second adjusting rod being rotatably connected to the outer top wall of the adjusting block, clamping assemblies being symmetrically arranged on the left side and the right side inside the adjusting block, a rotating assembly being transmittingly connected at the bottom ends of the two clamping assemblies, and snap-fit assemblies being transmittingly connected to the outer side of the rotating assembly; and a fixing module, comprising a fixing hoop arranged at the front end of the first adjusting rod, a fixing assembly being movably mounted at the front end of the fixing hoop. The apparatus can rapidly fix a radioactive source to an inspected pipeline, a focal length and an incident angle of the radioactive source are accurately determined, and it is guaranteed that the quality of a negative film meets the standard requirements. Moreover, the apparatus has the advantages of reasonable structural design, simple operation and high reliability and greatly improves the work efficiency.

The invention provides a microdosimetry-based evaluation method for a targeted alpha radionuclide treatment biological effective dose, and the method comprises the steps: carrying out the integration of a time activity curve of alpha radionuclide in an organ, obtaining the cumulative activity, and calculating the physical absorbed dose and dose rate of the organ through Monte Carlo simulation; based on micro-dose Monte Carlo simulation, constructing a micro-dose spectrum of the alpha radionuclide to obtain saturation correction dose average linear energy for representing radiation quality; obtaining biological effect parameters of the alpha radionuclide by fitting saturation correction dose average line energy and cell experiment data by using a micro-dose kinetic model; and evaluating the biological effective dose of the target organ in combination with the physical absorbed dose, the dose rate and the biological effect parameter. According to the method, the problem that a biological effective dose evaluation method is lacked in dose evaluation of targeted alpha radionuclide treatment is solved.

The invention provides a fluorescence-magnetic particle image fusion method which can be applied to the technical field of medical image processing. The method comprises the following steps: performing two-dimensional convolution processing on a registered two-dimensional near-infrared fluorescence image to obtain a multi-channel near-infrared fluorescence extended feature map, and performing initial fusion on the multi-channel near-infrared fluorescence extended feature map and a registered three-dimensional magnetic particle cross-sectional image to obtain a three-dimensional near-infrared fluorescence extended feature map; performing multi-round three-dimensional convolution processing on the three-dimensional near-infrared fluorescence extended feature map to obtain a multi-scale near-infrared fluorescence feature map, and performing multi-round three-dimensional convolution processing on the registered three-dimensional magnetic particle cross-sectional image to obtain a multi-scale magnetic particle feature map; and based on an adaptive cross attention mechanism, performing multi-round feature map fusion on the multi-scale near-infrared fluorescence feature map and the multi-scale magnetic particle feature map on the same scale, and performing filtering convolution processing on a multi-round feature map fusion result to obtain a three-dimensional fluorescence-magnetic particle fusion image.

The invention belongs to the technical field of evaluation, development and research of oil and gas reservoirs, and discloses a T2 cutoff value calculation method based on a saturated nuclear magnetic resonance experiment. The method comprises the following steps: acquiring a saturated / bound water nuclear magnetic resonance T2 spectrum curve of a compact sandstone sample; determining a T2 cut-off value based on a saturated / bound water nuclear magnetic resonance accumulative porosity curve, and recording the T2 cut-off value as T2-Cuff; acquiring a logT2-logphi intersection curve of the saturated nuclear magnetic resonance T2 spectrum, and recording a T2 value corresponding to an inflection point of the curve as T2-Log; and determining a mathematical relationship between the T2-Log and the T2-Cuff, and establishing a T2 cut-off value calculation model based on the saturated nuclear magnetic resonance experiment. According to the method, the T2 cutoff value can be calculated only by performing the nuclear magnetic resonance experiment on the saturated water sample and performing mathematical treatment on the T2 spectrum, and the method has the advantages of being economical, simple, efficient and high in practicability.

The invention relates to a material screening method and device based on muon transmission imaging, electronic equipment and a storage medium. The method comprises the steps that actually-measured muon track flux data and a cosmic ray muon flux model are acquired; according to the actual measurement muon track flux data, the cosmic ray muon flux model and the voxel discrete grid, determining an actual measurement muon blocking capability matrix; simulating penetration processes of cosmic ray muons in different track directions for multiple times according to the cosmic ray muon flux model to obtain multiple groups of simulated muon track flux data; according to the simulation muon track flux data, the cosmic ray muon flux model and the voxel discrete grid, determining a simulation muon prevention capability matrix; determining the coincidence degree of each prior material combination according to the actually measured muon prevention capability matrix and the plurality of simulated muon prevention capability matrixes of each prior material combination; and determining a material screening result according to the coincidence degree of each prior material combination. Therefore, the actual material composition in the to-be-detected object can be effectively discriminated.

The invention discloses a method and tool for manufacturing a cold shield of a nuclear fusion device, and relates to the technical field of metal plate machining. The manufacturing method of the cold shield of the nuclear fusion device comprises the following steps: providing a sub-panel, a flange and a pipe fitting; the multiple sub-panels are welded, and a first middleware is obtained; welding the edge of the first middleware and the turnup to obtain a second middleware; after the pipe fitting is welded to the surface of the second middleware, a third middleware is obtained; and the third middleware is shaped. According to the method, the third middleware is shaped, that is, the third middleware is shaped after all welding procedures are completed, so that the third middleware has relatively small profile tolerance, the profile tolerance of the cold shield meets the design requirement, the assembly difficulty of the cold shield is reduced, and the risk of failure of the cold shield is reduced.

The invention proposes a myocardial magnetic resonance image fibrosis classification method based on a convolutional neural network, and relates to the technical field of image processing, and the method comprises the steps: obtaining an original magnetic resonance image of a to-be-detected target from a magnetic resonance imaging device, and carrying out the preprocessing of the original magnetic resonance image; segmenting the preprocessed magnetic resonance image into a plurality of sub-regions based on the connected features, each sub-region representing an independent connected part in the image; constructing a gray scale measurement function for each sub-region, quantifying the gray scale distribution characteristics of each sub-region, and identifying the sub-region with the minimum gray scale measurement function value as a fibrosis tissue sub-region by comparing the gray scale measurement function values of the sub-regions; features are extracted from the identified fibrosis tissue sub-regions to serve as input of the convolutional neural network model, the fibrosis tissue sub-regions are classified, the fibrosis stages to which the fibrosis tissue sub-regions belong are output, and the accuracy of classification of the fibrosis tissue is improved.

A magnetic-based tracking system for tracking an ultrasound probe. The tracking system can create a three-dimensional visualization. The tracking system can include a reference device including a reference magnet and an ultrasound probe including an ultrasound acoustic transducer or acoustic array that acquires ultrasound images. The reference device can include a magnetometer that detects a magnetic field generated by the reference magnet. The ultrasound probe can couple a first ultrasound image with a first magnetic field strength, wherein both of the first ultrasound image is received and the first magnetic field strength is detected at a first time. The system can include a console including a processor and non-transitory computer-readable medium having stored thereon a plurality of processor executed logic modules that perform operations including receiving and recording a plurality of coupling of ultrasound images and detected magnetic field strengths to generate a 3D visualization from the ultrasound images.

The invention relates to an accelerated high-quality MRI (Magnetic Resonance Imaging) image reconstruction method based on a TC-KANReccon model. The method comprises the following steps: S1, collecting and preprocessing image data; s2, an accelerated high-quality MRI image reconstruction model based on a TC-KANReccon model is built; and S3, designing a noise cutting strategy of linear reduction of the cutting threshold. In each step of the sampling process, a linear decreasing cutting strategy is adopted according to the current progress of the sampling step. The strategy is applied to noise estimation generated by an MF-UKAN diffusion trunk so as to generate an MRI image with a better visual effect; s4, repeatedly training a diffusion model and a VAE module by taking the preprocessed MRI image and the full-sampling k-space data as input, optimizing network parameters, and continuously performing iterative optimization; and S5, inputting the under-sampled k-space data into the trained accelerated high-quality MRI image reconstruction model based on the TC-KANReccon model, and applying a matched noise cutting strategy of linear reduction of a cutting threshold to finally generate a high-quality MRI image.

The invention discloses a compressed sensing MRI (Magnetic Resonance Imaging) reconstruction method and system based on a double-domain fusion expansion model. The method comprises the following steps: acquiring an MRI image, preprocessing the MRI image to obtain a preprocessed image and a corresponding compressed sensing measurement value, and constructing a data set; training, testing and verifying the double-domain fusion expansion model by using the data set; and outputting a reconstructed image from the MRI image after mask sampling by using a double-domain fusion expansion model. According to the double-domain fusion expansion model, a complex convolutional neural network and a K-space attention mechanism are introduced for complex value data processing and double-domain information fusion in compressed sensing MRI reconstruction. The complex value data is processed through the complex network, the amplitude and phase information of the complex field is fully utilized, the detail recovery capability and the noise suppression effect of the model are enhanced, and particularly, excellent robustness is shown at a low sampling rate. The method is excellent in performance in complex MRI data reconstruction, and has high reconstruction precision and generalization ability.