Abstract: There is provided a method for determining material properties in an active acoustic spectroscopy system, the method comprising: acquiring a multidimensional acoustic spectrum from a material in a container using acoustic spectroscopy; reducing the dimensionality of the acoustic spectrum using a mathematical dimensionality reduction method, thereby forming a reduced acoustic spectrum describing a material state; and determining if the material state belongs to a predetermined material state cluster. There is also provided a system for performing the described method.

Abstract: There is provided a method for determining material properties in an active acoustic spectroscopy system, the method comprising: acquiring a multidimensional acoustic spectrum from a material in a container using acoustic spectroscopy; reducing the dimensionality of the acoustic spectrum using a mathematical dimensionality reduction method, thereby forming a reduced acoustic spectrum describing a material state; and determining if the material state belongs to a predetermined material state cluster. There is also provided a system for performing the described method.

Abstract: A holding arrangement for holding an acoustic transmitter in place in relation to a container. The arrangement comprises: a body comprising a cavity for holding an acoustic transmitter, the cavity comprising an opening arranged to face said container when said arrangement is attached to a container, wherein the body comprises acoustic damping material, and wherein the cavity is configured to permit movement of an acoustic transmitter in a direction perpendicular to a container surface and to restrict movement of the acoustic transmitter in directions not perpendicular to the container surface when an acoustic transmitter is arranged in said cavity and when said arrangement is attached to a container. There is also provided a measurement arrangement comprising such a holding arrangement.

Abstract: In the present invention a controllable acoustic source (14) in connection with the process fluid (10) emits a signal (18) into the fluid (10), consisting of a suspension of particles (12), being volumes of gas, liquid or solid phase. The controllable acoustic signal (18) is allowed to interact, with the particles (12), and the acoustic (pressure) signals (22) resulting from such an interaction is measured preferably via a sensor (24). A spectrum is measured. The spectrum is used to predict properties, content and/or size of the particles (12) and/or used to control a process in which the process fluid (10) participates. The prediction is performed in the view of the control of the acoustic source (14). The used acoustic signal has preferably a frequency below 20 kHz.

Abstract: In the present invention a controllable acoustic source (14) in connection with the process fluid (10) emits a signal (18) into the fluid (10), consisting of a suspension of particles (12), being volumes of gas, liquid or solid phase. The controllable acoustic signal (18) is allowed to interact, with the particles (12), and the acoustic (pressure) signals (22) resulting from such an interaction is measured preferably via a sensor (24). A spectrum is measured. The spectrum is used to predict properties, content and/or size of the particles (12) and/or used to control a process in which the process fluid (10) participates. The prediction is performed in the view of the control of the acoustic source (14). The used acoustic signal has preferably a frequency below 20 kHz.