A system includes an electrical tomography system and a volume estimation system. The volume estimation system is configured to reconstruct an initial impedance image based at least partially on received electrical tomography data of a domain, receive prior information associated with the domain, enhance the initial impedance image based at least partially on the received prior information to generate an enhanced impedance image, and based at least partially on the enhanced initial impedance image, generate a volumetric image of a region of interest of the enhanced impedance image, wherein the volumetric image represents a plurality of values indicating a volume of a fluid.

A device may be configured for performing signal processing in impedance sensing applications, and more specifically, for recovering data from an amplitude-modulated signal. In one aspect, a device includes a sensing circuit operable to sense an amplitude-modulated signal having a carrier frequency. The device also includes a mixer operable to mix the amplitude-modulated signal with a mixing signal having a mixing frequency to provide a frequency-downshifted signal having an intermediate frequency less than the carrier frequency. The device also includes a filter operable to filter the frequency-downshifted signal to provide a filtered signal. The device further includes a sampler operable to undersample the filtered signal at an undersampling frequency to provide a digital signal, the digital signal being representative of a modulating signal.

A device may be configured for performing signal processing in impedance sensing applications, and more specifically, for recovering data from an amplitude-modulated signal. In one aspect, a device includes a sensing circuit operable to sense an amplitude-modulated signal having a carrier frequency. The device also includes a mixer operable to mix the amplitude-modulated signal with a mixing signal having a mixing frequency to provide a frequency-downshifted signal having an intermediate frequency less than the carrier frequency. The device also includes a filter operable to filter the frequency-downshifted signal to provide a filtered signal. The device further includes a sampler operable to undersample the filtered signal at an undersampling frequency to provide a digital signal, the digital signal being representative of a modulating signal.

A method for determining a muscle section of a body part. The muscle section (S) is determined as a function of: at least two electrical resistance values measured through different electrodes located on different locations of the body, at least two electrodes being located along the body part, and a muscle conductivity constant (σ), and a permittivity constant of the muscle (ε).

A method for determining a muscle section of a body part. The muscle section (S) is determined as a function of: at least two electrical resistance values measured through different electrodes located on different locations of the body, at least two electrodes being located along the body part, and a muscle conductivity constant (σ), and a permittivity constant of the muscle (ε).

Systems, devices, and methods described herein relate to multi-sensory presentation devices, including virtual reality (VR) devices, visual display devices, sound devices, haptic devices, and other forms of presentation devices, that are configured to present sensory elements, including visual and/or audio scenes, to a user. In some embodiments, one or more sensors including electroencephalography (EEG) sensors and a photoplethysmography (PPG) sensors, e.g., included in a brain-computer interface, can measure physiological data of a user to monitor a state of the user during the presentation of the visual and/or audio scenes. Such systems, devices, and methods can adapt one or more visual and/or audio scenes based on user physiological data, e.g., to control or manage the state of the user.

A system for detecting an anomalous event in a person includes a body in contact with a skin surface of a person; a heat source for heating the skin surface to a target temperature; a skin temperature sensor for measuring a temperature of the skin surface in contact with the heat source; a blood volume sensor for measuring a blood volume of the skin surface; and a hardware processor communicatively coupled to the heat source, the blood volume sensor, the skin temperature sensor, and an environmental temperature sensor. The hardware processor is configured to receive a baseline blood volume signal, output a heating signal to the heat source to initiate a heating cycle, receive a second blood volume signal from the blood volume sensor, compare the second blood volume signal to the baseline blood volume signal, and determine whether an anomalous biologic event has occurred.

A signal processing apparatus includes a memory configured to store instructions; and a processor configured to execute the instructions to obtain a signal; obtain a frequency band spectrum by applying a Fast Fourier Transform (FFT) to the obtained signal; and remove noise from the obtained spectrum by applying a first filter and a second filter, which are different from each other, to the obtained frequency band spectrum.

A garment for detecting physiological data. The garment may include a garment body and a primary sensor panel affixed to a user facing side of the garment body. The primary sensor panel may include at least one bio signal sensor type to generate a primary set of bio signals. The garment may include a processor coupled to the primary sensor panel and a memory coupled to the processor. The memory may store processor-executable instructions that, when executed, configure the processor to: receive, from the primary sensor panel, the primary set of bio signals; generate a bio signal waveform based on the primary set of bio signals; and determine a hemodynamic metric associated with the user based on the bio signal waveforms associated with the user.

A method and system are provided for continuous monitoring perfusion of an organ or extremity, and for early detection of progressive partial occlusion of arterial blood supply or venous drainage of tissue. The method and system measure a delay in wave propagation of a blood perfusion wave, which is associated with flow of blood through a blood vessel. The delay is correlated to an amount of obstruction in the blood vessel.