A method of testing one or more analyte sensors each comprising a first electrode; a second electrode; and a material layer disposed on or above the first electrode; the method including (a) applying a voltage potential to the first electrode with respect to the second electrode; (b) measuring a test signal comprising an output current from the first electrode that results from the application of the voltage potential; (c) using the test signal from (b) to observe an electrical characteristic of the analyte sensor; and (d) correlating the electrical characteristic a parameter associated with an electrochemical response of the analyte sensor to an analyte, wherein the testing is under dry conditions without exposure of the electrodes to a fluid containing the analyte or an in-vivo environment containing the analyte.

Systems and methods for determining the composition of a drilling fluid using electro-rheology.

Systems and methods for assessing a microbial characteristic within a growing medium. Such a system assesses one or more microbial characteristics, such as biomass and/or microbial activity, within a growing medium, such as soil. Electrical properties of a microbially degradable material in contact with the growing medium are measured. The measurements are used to determine the microbial characteristic(s) based at least partly on degradation of the microbially degradable material.

Hundreds of thousands of concrete bridges and hundreds of billions of tons of concrete require characterization with time for corrosion. Accordingly, protocols for rapid testing and improved field characterization systems that automatically triangulate electrical resistivity and half-cell corrosion potential measurements would be beneficial allowing discrete/periodic mapping of a structure to be performed as well as addressing testing for asphalt covered concrete. Further, it is the low frequency impedance of rebar in concrete that correlates to corrosion state but these are normally time consuming vulnerable to noise. Hence, it would be beneficial to provide a means of making low frequency electrical resistivity measurements rapidly. Further, prior art techniques for electrical rebar measurements require electrical connection be made to the rebar which increases measurement complexity/disruption/repair/cost even when no corrosion is identified. Beneficially a method of determining the state of a rebar without electrical contact is taught.

Disclosed is a wireless monitoring system for a coal-gangue mixing ratio based on a non-Hermite technology, including a signal generation monitoring device, an excitation coil, a receiving coil and a parallel plate capacitor. The signal generation monitoring device is connected with the excitation coil; the receiving coil is connected with the parallel plate capacitor to form an LC resonance system; the receiving coil is placed in parallel with the excitation coil, and the axis of the receiving coil and the axis of the excitation coil are on a same horizontal line; the signal generation monitoring device is used to generate a pulse current and collect reflected signals; the excitation coil excites an initial magnetic field based on the generated pulse current, and the LC resonance circuit performs an electromagnetic field induction to generate an induced magnetic field, and feeds back the reflected signals to the signal generation monitoring device.

There is provided A method for producing an electrical impedance tomographic image of an acoustic field within a fluid, comprising the steps of: a) positioning a plurality of electrodes within a fluid; b) applying an electrical signal to each electrode within a first subset of electrodes, wherein the electrical signal applied to each electrode has a different carrier frequency and/or phase; c) measuring the electrical potential at each electrode within a second subset of electrodes; and d) processing the measured data to provide an acoustic map of the acoustic field at the required acoustic frequencies. There is also provided a system for producing an electrical impedance tomographic image of an acoustic field within a fluid using the method of any preceding claim, comprising a plurality of electrodes, a signal generator adapted to perform step (b), a device adapted to perform step (c), and a processor adapted to perform step (d).

Systems and methods for processing sensor data and self-calibration are provided. In some embodiments, systems and methods are provided which are capable of calibrating a continuous analyte sensor based on an initial sensitivity, and then continuously performing self-calibration without using, or with reduced use of, reference measurements. In certain embodiments, a sensitivity of the analyte sensor is determined by applying an estimative algorithm that is a function of certain parameters. Also described herein are systems and methods for determining a property of an analyte sensor using a stimulus signal. The sensor property can be used to compensate sensor data for sensitivity drift, or determine another property associated with the sensor, such as temperature, sensor membrane damage, moisture ingress in sensor electronics, and scaling factors.

A method of extracting complex impedance from selected volumes of the material under test (MUT) combined with various embodiments of electrode sensor arrays. Configurations of linear and planar electrode arrays provide measured data of complex impedance of selected volumes, or voxels, of the MUT, which then can be used to extract the impedance of selected sub-volumes or sub-voxels of the MUT through application of circuit theory. The complex impedance characteristics of the sub-voxels may be used to identify variations in the properties of the various sub-voxels of the MUT, or be correlated to physical properties of the MUT using electromagnetic impedance tomography and/or spectroscopy.

Systems and methods for measuring and monitoring physical properties of a material under test (MUT) from a vehicle, e.g., using complex electromagnetic impedance. Various embodiments include a method including: obtaining displacement data about a position of a sensor array relative to a material under test (MUT); comparing the displacement data with reference displacement data to determine whether the sensor array is at a reference distance relative to the MUT; in response to determining that the sensor array is located at the reference distance, instructing the sensor array to transmit a set of electromagnetic impedance signals into the MUT; obtaining a return electromagnetic impedance signal from the MUT; and calculating at least one physical property of the MUT based upon the transmitted set of electromagnetic impedance signals, the return electromagnetic impedance signals, and the displacement data.

Disclosed herein are a method for analyzing heavy metal removal efficiency using phase difference analysis and an apparatus using the method. The method for analyzing heavy metal removal efficiency using phase difference analysis includes applying a magnetic field to a magnetite onto which a heavy metal is adsorbed, based on a first solenoid coil and a second solenoid coil that have an identical winding direction, applying a high-frequency signal to the magnetite, based on a third solenoid coil having a winding direction that differs from that of the first solenoid coil and the second solenoid coil, detecting a high-frequency signal transformed by the magnetite, and calculating a phase difference between a previously detected default high-frequency signal and the transformed high-frequency signal, and analyzing an efficiency of heavy metal removal by the magnetite by measuring a concentration of the heavy metal based on the phase difference.