Methods and apparatus for non-invasive determination of one or more physical properties of a material in a conduit are presented. In one example, the method comprises initiating a vibration on a wall of the conduit at a first location, capturing a response to the vibration at the first location, capturing a response to the vibration at a second location, and determining at least one physical property of the material based on at least one of the captured responses at the first location and the second location.

Various systems and methods are provided for a mass flow rate sensor. In one example, a mass flow rate sensor comprises a first signal input, a second signal input, an output for a mass flow rate signal, a first characteristic field, a second characteristic field, each of the first and second characteristic fields associating a mass flow rate value with a pair of values of a revolution rate value and an output pressure value, and a selection unit that comprises a first parameter input and a second parameter input, the selection unit configured to produce a selection signal depending on a pair of parameters respectively received via the first and second parameter inputs and to switch the mass flow rate value of either the first or the second characteristic field through to the output of the mass flow rate sensor depending on the selection signal.

Various systems and methods are provided for a mass flow rate sensor. In one example, a mass flow rate sensor comprises a first signal input, a second signal input, an output for a mass flow rate signal, a first characteristic field, a second characteristic field, each of the first and second characteristic fields associating a mass flow rate value with a pair of values of a revolution rate value and an output pressure value, and a selection unit that comprises a first parameter input and a second parameter input, the selection unit configured to produce a selection signal depending on a pair of parameters respectively received via the first and second parameter inputs and to switch the mass flow rate value of either the first or the second characteristic field through to the output of the mass flow rate sensor depending on the selection signal.

A conveyor mechanism conveys a powder along a path. A first camera device arranged above the conveyor mechanism detects movement of a recognizable feature on an upper surface of the powder over a period of time. A velocity of the powder can be determined based on the movement of the recognizable feature over the period of time. A device can be used to generate the recognizable feature. A first light-emitting device can illuminate the upper surface to aid detection of the recognizable feature. A second light-emitting device can project a contour line on the upper surface, and a second camera device can be used to detect a position of the contour line. A cross sectional area of the powder can be correlated based on the position of the contour line.

A conveyor mechanism conveys a powder along a path. A first camera device arranged above the conveyor mechanism detects movement of a recognizable feature on an upper surface of the powder over a period of time. A velocity of the powder can be determined based on the movement of the recognizable feature over the period of time. A device can be used to generate the recognizable feature. A first light-emitting device can illuminate the upper surface to aid detection of the recognizable feature. A second light-emitting device can project a contour line on the upper surface, and a second camera device can be used to detect a position of the contour line. A cross sectional area of the powder can be correlated based on the position of the contour line.

Compositions and methods are provided for a system in which liquid carbon dioxide, or a mixture of liquid and gaseous carbon dioxide, is converted to solid carbon dioxide by exiting an orifice at a sufficient pressure drop, e.g., for delivery of carbon dioxide to a concrete mixture in a mixer.

Compositions and methods are provided for a system in which liquid carbon dioxide, or a mixture of liquid and gaseous carbon dioxide, is converted to solid carbon dioxide by exiting an orifice at a sufficient pressure drop, e.g., for delivery of carbon dioxide to a concrete mixture in a mixer.

A heater is provided that includes at least one resistive heating element having a material with a non-monotonic resistivity vs. temperature profile and exhibiting a negative dR/dT characteristic over a predetermined operating temperature range along the profile. The heater can include a plurality of circuits disposed in a fluid path to heat fluid flow.

A method for identifying a flow of commodity through a commodity distribution system. The method including providing a tank configured to contain a commodity, selectively distributing commodity from the tank to a drill assembly to be distributed to an underlying surface, and monitoring the flow of commodity from the tank to the drill assembly with a camera to identify flow characteristics.

A method for identifying a flow of commodity through a commodity distribution system. The method including providing a tank configured to contain a commodity, selectively distributing commodity from the tank to a drill assembly to be distributed to an underlying surface, and monitoring the flow of commodity from the tank to the drill assembly with a camera to identify flow characteristics.