A method and system for approximating a predicted three-dimensional imbibition phase saturation profile from a measured three-dimensional drainage phase saturation profile, a derived one-dimensional drainage phase saturation profile, a measured one-dimensional imbibition phase saturation profile using a trained machine-learning algorithm are disclosed. A method for training of the machine learning algorithm is also disclosed.

The invention relates to a system and a method for determining a characteristic of a blood vessel portion, which comprises blood including a contrast agent exhibiting resonant absorption of x-ray photons at a specific energy. The system comprises a tunable monochromatic x-ray source (21) emitting x-ray radiation, an x-ray detector device (22) for detecting the x-ray radiation after it has travelled through the blood vessel portion. A control unit (26) varies a tuning of the x-ray source (21) to vary the energy of the x-ray radiation emitted by the x-ray source (21), and an evaluation unit (27) determines a tuning of the x-ray source (21) at which nuclear resonant absorption of the x-ray radiation incident onto the blood vessel portion occurs and estimates the characteristic on the basis of the determined tuning. The characteristic may particularly be the blood velocity in the blood vessel portion.

A method for measuring counting rates or measured variables dependent on the counting rates for determining a density profile of at least two substances with different densities arranged within a container by using a plurality of detectors is provided. The method includes recording respective gamma rays which have penetrated at least partially through at least one of the substances by using the detectors, and generating a respective counting rate or a respective measured variable dependent on the counting rate only on the basis of respectively recorded gamma rays of which the respective gamma energy is greater than or equal to an energy threshold value, the energy threshold value being a minimum of 0.5 times a Compton energy value of a Compton gap of the gamma rays.

A method for measuring counting rates or measured variables dependent on the counting rates for determining a density profile of at least two substances with different densities arranged within a container by using a plurality of detectors is provided. The method includes recording respective gamma rays which have penetrated at least partially through at least one of the substances by using the detectors, and generating a respective counting rate or a respective measured variable dependent on the counting rate only on the basis of respectively recorded gamma rays of which the respective gamma energy is greater than or equal to an energy threshold value, the energy threshold value being a minimum of 0.5 times a Compton energy value of a Compton gap of the gamma rays.

A method for measuring counting rates or measured variables dependent on the counting rates for determining a density profile of at least two substances with different densities arranged within a container by using a plurality of detectors is provided. The method includes recording respective gamma rays which have penetrated at least partially through at least one of the substances by using the detectors, and generating a respective counting rate or a respective measured variable dependent on the counting rate only on the basis of respectively recorded gamma rays of which the respective gamma energy is greater than or equal to an energy threshold value, the energy threshold value being a minimum of 0.5 times a Compton energy value of a Compton gap of the gamma rays.

A method for measuring counting rates or measured variables dependent on the counting rates for determining a density profile of at least two substances with different densities arranged within a container by using a plurality of detectors is provided. The method includes recording respective gamma rays which have penetrated at least partially through at least one of the substances by using the detectors, and generating a respective counting rate or a respective measured variable dependent on the counting rate only on the basis of respectively recorded gamma rays of which the respective gamma energy is greater than or equal to an energy threshold value, the energy threshold value being a minimum of 0.5 times a Compton energy value of a Compton gap of the gamma rays.

A device configured to measure radioactivity emitted by a plurality of radionuclides is disclosed herein. The device includes a gamma detector and a source cage with an outer ring that defines a volume and includes an orientation feature and a plurality of holes configured to receive a radionuclide of the plurality of radionuclides. The device also includes a frame that includes an arm and a central rod, wherein the arm is configured to be coupled to the outer ring and includes an orientation pin. The central rod can be positioned relative to the volume when the arm is coupled to the outer ring of source cage. The orientation feature of the source cage is configured to engage the orientation pin of the arm and, when the orientation pin engages the orientation feature, the central rod is in a predetermined location relative to the volume.

A device configured to measure radioactivity emitted by a plurality of radionuclides is disclosed herein. The device includes a gamma detector and a source cage with an outer ring that defines a volume and includes an orientation feature and a plurality of holes configured to receive a radionuclide of the plurality of radionuclides. The device also includes a frame that includes an arm and a central rod, wherein the arm is configured to be coupled to the outer ring and includes an orientation pin. The central rod can be positioned relative to the volume when the arm is coupled to the outer ring of source cage. The orientation feature of the source cage is configured to engage the orientation pin of the arm and, when the orientation pin engages the orientation feature, the central rod is in a predetermined location relative to the volume.

A method including: manufacturing a standard transmission object; simulating a transmission measurement process using simulation calculation method, to establish a database with respect to a transmission thickness, an equivalent water density, an original reconstruction density of the standard transmission object, a space angle cosine of the transmission source and an energy of a γ ray, fitting a corresponding relationship of the space angle cosine of the transmission source with respect to parameters of the standard transmission object and the energy of the γ ray based on the database; selecting a corresponding standard transmission object for transmission measurement for a transmission source to be characterized, to obtain an original reconstruction density of the standard transmission object; reading the space angle cosine of the transmission source to be characterized from the database according to fitted corresponding relationship of known parameters of the standard transmission object and the energy of the γ ray.

A method including: manufacturing a standard transmission object; simulating a transmission measurement process using simulation calculation method, to establish a database with respect to a transmission thickness, an equivalent water density, an original reconstruction density of the standard transmission object, a space angle cosine of the transmission source and an energy of a γ ray, fitting a corresponding relationship of the space angle cosine of the transmission source with respect to parameters of the standard transmission object and the energy of the γ ray based on the database; selecting a corresponding standard transmission object for transmission measurement for a transmission source to be characterized, to obtain an original reconstruction density of the standard transmission object; reading the space angle cosine of the transmission source to be characterized from the database according to fitted corresponding relationship of known parameters of the standard transmission object and the energy of the γ ray.