48 results about "Radiation damping" patented technology

Described is a radiation dosimeter including multiple sensor devices (including one or more passive integrating electronic radiation sensor, a MEMS accelerometers, a wireless transmitters and, optionally, a GPS, a thermistor, or other chemical, biological or EMF sensors) and a computer program for the simultaneous detection and wireless transmission of ionizing radiation, motion and global position for use in occupational and environmental dosimetry. The described dosimeter utilizes new processes and algorithms to create a self-contained, passive, integrating dosimeter. Furthermore, disclosed embodiments provide the use of MEMS and nanotechnology manufacturing techniques to encapsulate individual ionizing radiation sensor elements within a radiation attenuating material that provides a “filtration bubble” around the sensor element, the use of multiple attenuating materials (filters) around multiple sensor elements, and the use of a software algorithm to discriminate between different types of ionizing radiation and different radiation energy.

Disclosed herein is a method and apparatus for providing radiation shielding for non-invasive inspection systems. An embodiment of the apparatus may include a radiation shield having a plurality of slats, where each of the plurality of slats comprises a radiation attenuating material. The radiation shield may further include a support structure configured to hold the slats in a non-planar shape. An embodiment of the method may include gathering a plurality of slats, each slat comprising a radiation attenuating material. The method may further include disposing the slats to form a shielding curtain having a non-planar shape. The method may also include positioning the shielding curtain to cover an opening of a scanner.

A multi-ply, preferably flexible, x-ray shielding material which can be formed into a garment is provided. Such material is lighter in weight but that provides a specific degree of protection under the standard conditions met in fluoroscopy by workers in the field subjected to reflected, or scattered, radiation emanating from the patient's body. The multi-layered fabric is so constructed that the amount of re-radiated energy, or fluorescence produced by each layer, is greatly attenuated. Generally, this invention is directed to a material formed of two or more layers of a polymeric or elastomeric film or sheet loaded with different radiation-attenuating metal material.

Radiation damping (RD) is employed to hasten the recovery of longitudinal magnetization after RF excitation and signal readout in a magnetic resonance measurement cycle. A switch driven by the pulse sequence that performs the measurement cycle energizes a feedback RF coil driven by an amplified and phase shifted portion of the received MR signal. The recovery of longitudinal magnetization is thus under direct control of the MR system and enables the reduction of the otherwise inefficient waiting times that are required for natural T1 recovery of the excited spin magnetization. This enables shortened acquisition times, improved sensitivity, better spatial and temporal resolution, and reduction of motion artifacts that result from long acquisition times.

An imaging system including an imaging apparatus having a plurality of coils, wherein an imaging target is at least partially disposed proximate the coils with at least one excitation source providing pulse sequences. A switch switchably connects the pulse sequences from the excitation source to the coils and switchably connecting to spatially encoded images from the coils during data acquisition. There is an amplified radiation damping feedback section providing amplified radiation damping feedback to the imaging target, wherein the amplified radiation damping feedback provides recovery of longitudinal magnetization subsequent to the data acquisition, and a receiver section for processing the spatially encoded images.

The invention discloses an NMR nuclear magnetic resonance method for high flux medicine screening. The method includes the following steps: a, preparing mixed water solution containing target biomacromolecules and to-be-screened medicine, and adding the target biomacromolecules and to-be-screened molecules in the water solution and uniformly mixing the biomacromolecules and the to-be-screened molecules as well as the water solution; b, filling the mixed solution in an NMR sample tube, placing the sample tube in a spectrometer, and selectively detecting signals of ligand molecules combined with the target protein, wherein the selective detection includes the steps that firstly, building the selective disturbance for water serving as the resolvent based on the radiation damping effect, secondly, performing the operation based on the effects such as exchange and polarization transfer, and thirdly, exciting the built signals, and selectively detecting the protein and the ligand molecules of the protein, wherein the operation includes two pulse modular units, namely, a signal building module and a detection module; and c, completing the molecule confirmation. The method is simple and convenient to operate and feasible, has high accuracy and sensitivity in experiment detection, and effectively improves the accuracy and efficiency in medicine screening.

Wearable radio-opaque shields may be formed from relatively low-cost materials, which may include a non-toxic radio-opaque material. The use of such materials may render the wearable radio-opaque shields suitable for limited use or even for single use. The useful life of a wearable radio-opaque shield may be extended, and hygiene improved, by way of a liner configured for assembly with the wearable radio-opaque shield. Methods for using and disposing of wearable radio-opaque shields and liners are also disclosed.

An optical absorption gas sensor includes a radiation source, detector and a radiation guide. The radiation source and detector are close together and in thermal communication. The radiation guide has a rectangular cross section and curves in a first sense, around an axis parallel to the major dimension of the rectangular cross section, and then in a second opposite sense, and again in the first sense. A relatively long path for radiation is provided in a compact device, without the attenuation of radiation which would occur if the radiation guide did not have a rectangular cross section and curved only around an axis parallel to the major dimension of the rectangular cross section. A reference measurement can be obtained by mounting a reference radiation source behind a translucent measurement radiation source and directing radiation from the reference radiation source through the measurement radiation source. Radiation from a reference radiation source may be directed around the measurement reference source. Measurement and reference signals can be obtained by using a light emitting diode to generate radiation which is detected by a photodiode, in a first operating mode, and driving the photodiode to generate radiation having a different emission spectrum while detecting the resulting radiation using the light emitting diode, in a second operating mode. An optical absorption gas sensor may be manufactured by abutting two or more L-shaped radiation guide portions to form a radiation guide. The radiation guide has an interior surface operable to reflect radiation emitted by the radiation source of the optical absorption gas sensor.

In a method and an apparatus for automatic determination of objects that attenuate high energy / penetrating radiation by magnetic resonance, the magnetic resonance apparatus scans and prepares MR images, and the MR images contain information about the T2 relaxation time constant. Subsequently, penetrating radiation-attenuating objects are determined in the MR images by means of the T2 relaxation time constant.

A shielded head cover in accordance with an embodiment of the present application includes at least one attenuation portion including a radiation attenuating material configured and operable to protect a user head from radiation. The attenuation portion may include a varying amount of radiation attenuating material at different locations to provide for increased protection at desired locations. The attenuation portion may be embodied as a removable patch that is attached to the head cover. The attenuation portion may be provided by spraying particles of radiation attenuating material on the head cover. The attenuation portion may be embodied as a headband configured to be wrapped around a user's head and including attenuating material positioned in a pocket or cavity therein.

The invention belongs to the technical field of geotechnical engineering and foundation engineering and relates to a bridge pile foundation anti-earthquake analysis simplified method considering the whole soil liquefaction process in the field of earthquake engineering. The method comprises the steps that a model calculation parameter reasonable determining method and a concrete expression are given out by building a liquefied site pile-soil earthquake interaction macrocell model which well considers the influence on a soil spring of the pile-soil earthquake interaction from sand liquefaction and is used for achieving the process of the pile-soil earthquake interaction; then based on a non-linear Winkler foundation beam model, the built macrocell model is adopted, mass inertia force of soil, participating in vibration, around a pile, inertia force of an upper structure, radiation damping of soil and other effects are considered, a liquefied site pile-soil-bridge beam structure earthquake interaction simplified analysis model is built, soil movement and pore pressure ratio time interval obtained by implementing free liquefaction site power analysis serve as numerical model external input and are used for liquefied site pile-soil earthquake interaction problem analysis, and a new analysis method is provided for actual liquefied site bridge pile foundation anti-earthquake design.

A modulator for use in a radiation system with directional radiation beams respectively collimated into radiation fields, including a plurality of displaceable radiation attenuating elements arranged in at least one row, the radiation attenuating elements being configured to attenuate portions of a radiation beam inside the radiation field according the position of the radiation attenuating elements, and wherein each radiation attenuating element is respectively attached to a substantially radiolucent member, and a driver operable to store motion profiles and to respectively drive the radiation attenuating elements in directions generally perpendicular to the radiation beam via the substantially radiolucent members, wherein the respective motions of the radiation attenuating elements are according to corresponding motion profiles, and wherein a motion profile relates position and / or velocity of the radiation attenuating elements to time and / or irradiation level.

Lightweight and rigid, leaded or lead-free integral radiation shielding structural compositions comprising two or more radiation attenuating elements or compounds thereof, selected for having compatible radiation attenuating characteristics, dispersed in a thermoplastic or thermoset resin. The radiation shielding structural compositions of the present invention can be used to functionally and structurally replace lead-lined structures in medical and industrial x-ray systems. The radiation shielding structural compositions of the present invention can also be formulated to minimize the density of the resulting structure.

For use in or with a satellite receiving system having a receiving element such as low noise amplifier, a selectively variable RF signal attenuator locatable between the satellite and the amplifier comprises an RF radiation shield having at least one selectively variable radiation-passing area. The radiation shield comprises a plurality of overlapped shield members having selectively overlapped openings, movement of one member relative to the other causing the effective intersection defining a radiation-passing area of the shield to vary. According to a disclosed method, after locating a radiation attenuator as described between the satellite and the amplifier, the signal received from the satellite is variably attenuated using the signal attenuator until the signal level of the received radiation is within a range of an associated signal indicator wherein the indicator's response is more linear than it is at higher signal levels. The position of the collector is then adjusted until the indicator output peaks. Finally, the attenuation is reduced or eliminated to permit normal operation of the satellite receiving system.

The present invention relates to a method for detecting an analyte (10) in a sample, comprising the steps of: providing a transducer comprising a pyroelectric or piezoelectric element and electrodes which is capable of transducing a change in energy to an electrical signal, a first reagent immobilised on the transducer, and a second reagent (11) releasably bound to the first reagent and having a label attached thereto which is capable of absorbing electromagnetic radiation to generate energy by non-radiative decay, wherein either the first or second reagent has a binding site which allows binding to the other and which is capable of preferentially binding to the analyte or a derivative of the analyte; exposing the transducer to the sample thereby allowing the analyte or a derivative of the analyte to bind to the binding site and displace the second reagent; irradiating the sample with electromagnetic radiation; transducing the energy generated into an electrical signal; and detecting the electrical signal. The invention also provides a device for carrying out the method.

The invention discloses a device used for simulating a foundation radiation damping effect in a vibration table test, and relates to the device used for simulating the radiation damping effect in a vibration table model test for a large-scale underground structure and a hydraulic structure. Flaky rubber sacs are arranged between the side wall inside a model box and model soil in the model box of a vibration table; the number of the rubber sacs is an even number greater than 2; the rubber sacs are respectively attached to the side surface inside the model box uniformly; the rubber sacs opposite to each other in pairs are respectively communicated with each other through flexible conduit tubes respectively; and the interior of each rubber sac is filled with sponge and water. When the model box filled with the model soil is under the action of seismic excitation in the horizontal direction, a model soil body moves reciprocally in the horizontal direction; in the moving process of the model soil, the water in the rubber sac flows in the sponge and the flexible conduit tubes; when the water flows through the sponge, volume resistance to the movement of the water is generated by the sponge to consume energy; moreover, the water in the flexible conduit tubes moves reciprocally at the speed which is several times that of the model soil so as to adsorb and consume radiation energy. Thedevice simulates the foundation radiation damping effect very well.

The invention relates to a heaving acceleration-based semi-submersible ocean platform heaving motion parameter prediction method, which comprises the following steps of: in heaving motion, ignoring the coupling influence of additional mass and radiation damping based on a linear potential flow theory, and representing heaving acceleration; considering the noise influence of the actually measured marine environment, the low-frequency influence caused by slow change of the environment and the influence caused by the baseline drift error of the acceleration sensor, introducing a noise item, a low-frequency change item and a baseline drift error item, and carrying out unified Prony sequence normalization representation on the noise item, the low-frequency change item and the baseline drift error item; and performing drift term removal on the heaving acceleration after normalization representation, establishing a relational expression between the heaving acceleration and heaving motion parameters through the residual Prony sequence after drift term removal, and estimating the heaving motion parameters. Compared with a traditional method based on a filter, the method has the advantages that heaving motion parameters are estimated through the Prony sequence, and higher calculation precision is achieved.

The invention provides a test method for wind resistance of transmission towers. A 'mass-elasticity-resistance' model is adopted. A foundation and a basis system are regarded as mass steel blocks on spring and damper supports, and the spring, the damper and the mass steel blocks constitute a dynamic motion system together. The static stiffness of the foundation soil is simulated by the stiffness of the spring, and the radiation damping and material damping of the foundation soil are simulated by the damping of the damper. The stiffness coefficient and damping coefficient of the actual soil aredetermined by doing statistics of the physical properties of the soil and the parameters such as the shear modulus. According to the method, the four independent foundations of a transmission power are combined into a whole foundation, so that the structure is simpler. Before simplification, the four foundations need to be simulated separately. After simplification, only one foundation needs to be simulated. The operation is made simpler, and the workload is saved.