42 results about "Energy dependent" patented technology

A baggage scanning system and method employ combined angular and energy dispersive x-ray scanning to detect the presence of a contraband substance within an interrogation volume of a baggage item. The interrogation volume is illuminated with penetrating, polychromatic x-rays in a primary fan beam from a source such as a tungsten-anode x-ray tube. An energy-dependent absorption correction is determined from measurement of the attenuation of the fan beam at a plurality of different energies. Radiation coherently scattered by substances in the interrogation volume is detected by an energy-resolved x-ray detector operated at a plurality of scattering angles to form a plurality of scattering spectra. Each scattering spectrum is corrected for energy-dependent absorption and the corrected spectra are combined to produce a scattering pattern. The experimental scattering pattern is compared with reference patterns that uniquely characterize known contraband substances. The system and method can locate and identify a wide variety of contraband substances in an accurate, reliable manner. The system provides for automated screening, with the result that vagaries of human performance are virtually eliminated. False alarms and the need for hand inspection are reduced and detection efficacy is increased.

Parameters being a measure for a characteristic of a channel or of a pair of channels, wherein the parameter is a measure for a characteristic of the channel or of the pair of channels with respect to another channel of a multi-channel signal can be quantized more efficiently using a quantization rule that is generated based on a relation of an energy measure of the channel or the pair of channels and an energy measure of the multi-channel signal. With generation of the quantization rule taking into account a psycho acoustic approach, the size of an encoded representation of the multi-channel signal can be decreased by coarser quantization without significantly disturbing the perceptual quality of the multi-channel signal when reconstructed from the encoded representation.

Parameters being a measure for a characteristic of a channel or of a pair of channels, wherein the parameter is a measure for a characteristic of the channel or of the pair of channels with respect to another channel of a multi-channel signal can be quantized more efficiently using a quantization rule that is generated based on a relation of an energy measure of the channel or the pair of channels and an energy measure of the multi-channel signal. With generation of the quantization rule taking into account a psycho acoustic approach, the size of an encoded representation of the multi-channel signal can be decreased by coarser quantization without significantly disturbing the perceptual quality of the multi-channel signal when reconstructed from the encoded representation.

For correcting differential phase image data 52, differential phase image data 52 acquired with radiation at different energy levels is received, wherein the differential phase image data 52 comprises pixels 60, each pixel 60 having a phase gradient value 62a, 62b, 62c for each energy level. After that an energy dependent behavior of phase gradient values 62a, 62b, 62c of a pixel 60 is determined and a corrected phase gradient value 68 for the pixel 60 is determined from the phase gradient values 62a, 62b, 62c of the pixel 60 and a model for the energy dependence of the phase gradient values 62a, 62b, 62c.

The invention is directed to a corrector for correcting energy-dependent first-order aberrations of the first degree as well as third-order spherical aberrations of electron-optical lens systems. The corrector includes at least one quadropole septuplet (S1) having seven quadrupoles (Q1 to Q7). The quadrupoles are mounted symmetrically to a center plane (ZS) so as to permit excitation along a linear axis. The corrector furthermore includes at least five octopoles (O1 to O7) which can be excited within the quadrupole septuplet. In an advantageous embodiment, two quadrupole septuplets are mounted in series one behind the other. The quadrupole fields of the two quadrupole septuplets are excited antisymmetrically to a center plane lying between the two quadrupole septuplets. With such a system, all geometric third-order aberrations and additional energy-dependent first-order aberrations of the third degree and geometric fifth-order aberrations of a lens system can be corrected in addition to the axial and off-axial first-order chromatic aberrations of the first degree.

A volume calibration phantom is disclosed in the present invention, which comprises a container; a plurality of plates stacking up inside the container; and at least one slab of radioactive source, each of which is disposed between the adjacent plates and comprises a plurality of radionuclides. With the volume calibration phantoms, the present invention further provides a calibration method which is an improvement over conventional calibration methods of space geometric center point source and relative penetration factor ratios. The method comprises the steps of generating a calibration curve of density vs. counting efficiency corresponding to the several different volume calibration phantoms; calculating the density of a radioactive waste specimen to obtain a corresponding radioactive activity according to the calibration curve, and then revising the corresponding radioactive activity according to the energy dependency and equation of gamma gross radioactivity for multiple radionuclides so as to obtain the correct gamma gross radioactivity of the radioactive waste specimen. By means of the method disclosed in the present invention, a precise and accurate result can be obtained.

The invention relates to an imaging system for imaging a region of interest from energy-dependent projection data, wherein the imaging system comprises a projection data providing unit (1, 2, 3, 6, 7, 8) for providing energy-dependent first projection data of the region of interest. The imaging system comprises further an attenuation component image generation unit (12) for generating attenuation component images of the region of interest by generating energy-dependent second projection data using a model in which the projection data depend on attenuation component images. The component image generation unit (12) is adapted for generating the attenuation component images such that deviations of the second projection data from the first projection data are reduced.

Parameters being a measure for a characteristic of a channel or of a pair of channels, wherein the parameter is a measure for a characteristic of the channel or of the pair of channels with respect to another channel of a multi-channel signal can be quantized more efficiently using a quantization rule that is generated based on a relation of an energy measure of the channel or the pair of channels and an energy measure of the multi-channel signal. With generation of the quantization rule taking into account a psycho acoustic approach, the size of an encoded representation of the multi-cha nnel signal can be decreased by coarser quantization without significantly disturbing the perceptual quality of the multi-channel signal when reconstructed from the encoded representation.

The invention discloses an ultra-low power consumption passive structural strain monitoring device, comprising a radio frequency front end, an ultra-low power consumption MCU, a strain detection module and a super-capacitor, wherein the radio frequency front end comprises a dipole antenna, a rectification voltage-multiplying voltage stabilization module, a demodulation and an emission module. The device can be embedded in a building structure to collect structural strain parameters, return structural strain change information to a reader in a wireless communication mode, and solve the problems of energy dependence and inconvenience of structural stain monitoring based on the wireless sensor network technology; in addition, the device does not need batteries for power supply, and can work for a long time without extra maintenance.

There is provided a method for determining an energy level of a physical system using a quantum computer, wherein the energy level of the physical system is described by the summation of a plurality of summands. The method comprises performing an energy estimation routine which comprises preparing an ansatz trial state using an arrangement of quantum gates, wherein the ansatz trial state has a trial state energy dependent on a trial state variable, and estimating an expectation value of each summand respectively. The estimating comprises constructing, based on the arrangement of quantum gates,an initial quantum circuit to operate on the ansatz trial state and further comprises performing a summand expectation value determination sub- routine a plurality of times in an iterative process. The energy estimation routine further comprises summing the expectation value estimates of each summand to determine an estimate for the trial state energy. The method further comprises determining theenergy level of the physical system by applying an optimisation procedure to the energy estimation routine, wherein the optimisation procedure comprises iteratively updating the trial state variableand performing the energy estimation routine a plurality of times to determine a respective trial state energy for each of a plurality of different ansatz trial states.

A method for improving the ability to recognize materials in an X-ray inspection system is provided that includes the steps of recording at least two absorption X-ray images of an object to be examined at different energies, mathematically modeling the object by a number of layers assuming a particular material for each layer, wherein an absorption value describes the absorptivity of a layer, the number of layers is less than or equal to the number of X-ray images and at least one layer is assumed to be a material to be recognized during the inspection, decomposing the absorption value of each layer into a path-dependent factor and an energy-dependent factor, calculating the path-dependent factors for all layers from the absorption X-ray images using the absorption equation, calculating at least one synthetic image from the sum of all layers of the product of the absorption values and the weighting factors, evaluating the synthetic image.

In an imaging method, estimated data is iteratively projected and backprojected. The iterative projecting and backprojecting includes projecting or backprojecting the estimated data along parallel paths each employing energy-dependent parameters appropriate for a different energy. During each iteration, the estimated data is adjusted based on comparison of the estimated data with measured data.

For correcting differential phase image data 52, differential phase image data 52 acquired with radiation at different energy levels is received, wherein the differential phase image data 52 comprises pixels 60, each pixel 60 having a phase gradient value 62a, 62b, 62c for each energy level. After that an energy dependent behavior of phase gradient values 62a, 62b, 62c of a pixel 60 is determined and a corrected phase gradient value 68 for the pixel 60 is determined from the phase gradient values 62a, 62b, 62c of the pixel 60 and a model for the energy dependence of the phase gradient values 62a, 62b, 62c.

The invention relates to a system (31) for generating spectral computed tomography projection data. A spectral projection data generation device (6) comprising an energy-resolving detector generates spectral computed tomography projection databased on polychromatic radiation (4), which has been provided by a radiation device (2), after having traversed an examination zone (5), and a reference values generation device generates energy-dependent reference values based on radiation, which has not traversed the examination zone. A spectral parameter providing unit (12) provides a spectral parameter being indicative of a spectral property of the radiation device based on the energy-dependent reference values. In particular, spectral properties of the radiation device can be monitored over time, wherein this information can be used for, for instance, correcting the spectral computed tomography projection data, and / or, if undesired spectral properties of the radiation device are indicated, triggering a replacement of the radiation device.

A structure composed of multiple layers that consist of 7 stages of photon and electron management, enhancement, and conversion for the purposes of photovoltaic applications is described. The invention consists of one or more layers comprised of: 1) an energy dependent up and down conversion layer optimized for a particular wavelength such as infrared; 2) a layer for multiple implementations of light capturing and trapping; 3) a layer for photonic and plasmonic enhancement of captured and trapped light; 4) a layer for converting photons to electrons; 5) a layer for multiplying electrons; 6) a layer for storing generated electrons; and 7) a layer for using electrons for power. One or more layers may serve simultaneous purposes.

A volume calibration phantom comprises a container; a plurality of plates stacking up inside the container; and at least one slab of radioactive source, each of which is disposed between the adjacent plates and comprises a plurality of radionuclides. With the volume calibration phantoms, the present invention further provides a calibration method which is an improvement over conventional calibration methods of space geometric center point source and relative penetration factor ratios. The method comprises the steps of generating a calibration curve of density vs. counting efficiency corresponding to the several different volume calibration phantoms; calculating the density of a radioactive waste specimen to obtain a corresponding radioactive activity according to the calibration curve, and then revising the corresponding radioactive activity according to the energy dependency and equation of gamma gross radioactivity for multiple radionuclides so as to obtain the correct gamma gross radioactivity of the radioactive waste specimen.

A method and an X-ray system are disclosed for generating a phase contrast image of an examination object. In an embodiment, the distribution of an electron density in the examination object is determined by defining energy-dependent attenuation values for X-radiation with at least two different X-ray energy spectra, phase-shift values are obtained from the previously determined electron density distribution, and a phase contrast image is generated from the calculated phase-shift values.

The invention relates to a detection values processing apparatus. Energy-dependent detection values are provided, which are indicative of polychromatic radiation (4) after having traversed an examination zone (5). The radiation is filtered by a filter (15) which comprises K-edge filter material. A component decomposition technique is applied to the detection values for determining K-edge attenuation values being first component attenuation values, which are indicative of an attenuation caused by the K-edge filter material, and additional component attenuation values, which are indicative of an attenuation caused by additional components of the examination zone, wherein an image of the examination zone is reconstructed from the additional component attenuation values. An image can therefore be reconstructed, which is not adversely affected by the filter, because the K-edge attenuation values are not used for reconstructing the image. This can improve the quality of the reconstructed image.