Abstract: A method, system, device, and medium for online stress monitoring without baseline data based on single-mode multi-frequency signal fusion are provided.

Abstract: The disclosure provides a method, system, device and medium for online monitoring of a plane stress field without baseline data based on a piezoelectric transducer array. Since Lamb waves have complex multi-mode characteristics, a suitable excitation frequency needs to be selected according to geometric dimensions of the structure to be measured, and then, only low-order mode Lamb waves are excited inside the measured structure to avoid serious waveform aliasing. For isotropic measured objects, anisotropic characteristics will be generated under the action of pre-stresses, that is, the propagation velocities of ultrasonic waves in all directions are different, but there is a linear relationship between velocity changes in different propagation directions and stresses. Therefore, there is still a linear relationship between the difference of velocity changes in different propagation directions and the stress.

Abstract: An automated cell culture system includes a cell culture reactor including a housing; a fluidic circuit for cell culture media, the fluidic circuit disposed in an interior of the housing. The fluidic circuit includes a culture vessel for culturing cells in the cell culture media, a reservoir for the cell culture media, the reservoir fluidically connected to the culture vessel, and a pump configured to pump the cell culture media in the fluidic circuit. The automated cell culture system includes one or more sensors disposed in the interior of the housing, each sensor configured to detect a parameter of one or more of (1) the cell culture media in the fluidic circuit and (2) an environment in the interior of the housing; and a computing device configured to automatically control operation of the cell culture reactor based on one or more of the detected parameters.