Abstract: A radio frequency (RF) sensing device in an assembly is adapted to wirelessly communicate with a remote transceiver. The sensing device includes a substrate; an antenna disposed on the substrate; an electronic circuit disposed on the substrate and electrically coupled to the antenna; a heating element electrically coupled to the electronic circuit for heating a target area; and a sensing element thermally coupled to the heating element for sensing a temperature of the heating element. The RF sensing device is configured to wirelessly receive a power and provides the power to the heating element.

Abstract: Systems and methods are provided for determining sensor or infrastructure placement in a fluid network, for determining an anomaly of interest in the fluid network, and for optimally determining sensor coverage in a fluid network, which are based on a model of the fluid network represented by a directed graph.

Abstract: Systems and methods for generating random bits by using physical variations present in material samples are provided. Initial random bit streams are derived from measured material properties for the material samples. In some cases, secondary random bit streams are generated by applying a randomness extraction algorithm to the derived initial random bit streams.

Abstract: At least some aspects of the present disclosure feature a mobile sensing system comprising a sensing device for measuring a thermal property of an object, comprising an RF circuit and an antenna electronically coupled to the RF circuit, a sensor electronically coupled to the RF circuit, and a thermal source thermally coupled to the sensor and electronically coupled to the RF circuit, a mobile device having a processor, an RF reader connected to or integrated with the mobile device, wherein the RF reader is configured to interrogate the sensing device; wherein the sensing device receives power when the RF reader interrogates the sensing device and provides at least a portion of the power to the thermal source.

Abstract: A portable sensor for measuring a hydration level of an object in close physical proximity with the sensor includes a portable housing having a total volume of less than about 50 cm3. First circuitry disposed in the housing includes a thermal source, a controller electrically coupled to the thermal source, a temperature sensing element, and a processor coupled to the temperature sensing element. When the object is in close physical proximity with the sensor, the thermal source is energized by the controller with a signal having a known function of time. The object affects a time variation of a temperature of the thermal source, the temperature sensing element senses the affected time variation of the temperature of the thermal source, and the processor determines a hydration level of the object based on a characteristic of the affected time variation of the temperature of the thermal source.

Abstract: Some aspects of the present disclosure feature a system for sensing a change in environment comprising a MMR sensor and a reader. The MMR sensor is configured to be disposed in the environment. The MMR sensor comprises a magnetic bias layer, a resonator, a spacer, and an environmental change receptor. The reader is configured to measure a frequency characteristic of the MMR sensor after the environmental variable changes and the change to the environmental variable is evaluated based on the frequency characteristic.

Abstract: A system for use in wirelessly monitoring a pipeline such as a natural gas pipe. The system includes a locator configured to wirelessly transmit power and a subsoil sensor marker located adjacent the pipe and configured to wirelessly communicate with the locator. The sensor marker includes a microcontroller, a memory module, a sensor configured to sense the presence of a gas, and a power module. The power module is configured to harvest a sufficient amount of the power wirelessly transmitted from the locator in order to operate the microcontroller to take a measurement via the sensor, save the measurement in the memory module, and wirelessly transmit the measurement to the locator.

Abstract: In general, techniques are described for filter media monitoring within a filtration system. The filter media monitoring techniques described herein include, for example, direct contact with the filter media, e.g., a sensor may be located inside a boundary defined by a surface of the filter media, or indirect contact with the filter media, e.g., a sensor may be located outside the boundary defined by the surface of the filter media such that the sensor does not make direct physical contact with the filter media being monitored.

Abstract: A shoe degradation sensor assembly includes a first sensor disposed in or proximate to a material layer of a shoe between a foot space and an outer surface of the shoe, and an electrical contact assembly operable to removably electrically connect the shoe degradation sensor assembly to a reader. The material layer changes in at least one physical property with degradation to the shoe, and the first sensor is configured to indicate the changing physical property of the material layer thereby indicating a degree of degradation to the shoe.

Abstract: A radio frequency (RF) sensing device in an assembly is adapted to wirelessly communicate with a remote transceiver. The sensing device includes a substrate; an antenna disposed on the substrate; an electronic circuit disposed on the substrate and electrically coupled to the antenna; a heating element electrically coupled to the electronic circuit for heating a target area; and a sensing element thermally coupled to the heating element for sensing a temperature of the heating element. The RF sensing device is configured to wirelessly receive a power and provides the power to the heating element.

Abstract: Systems and methods for generating random bits by using physical variations present in material samples are provided. Initial random bit streams are derived from measured material properties for the material samples. In some cases, secondary random bit streams are generated by applying a randomness extraction algorithm to the derived initial random bit streams.

Abstract: At least some aspects of the present disclosure feature a radio frequency identification (RFID) tag adapted to wirelessly communicate with a remote transceiver. The RFID tag includes a substrate; and first and second circuits disposed on the substrate and comprising respective first and second antennas magnetically coupled to one another. At least some aspects of the present disclosure feature a RFID tag having a plurality of RF circuits, where each RF circuit is electronically coupled to a sensing element.

Abstract: At least some aspects of the present disclosure feature an RF interface device. The RF interface device comprises an RF receiver, a wireless reader and an output component. The RF receiver is configured to receive power wirelessly. The wireless reader is configured to interrogate a wireless device. The wireless reader is further configured to provide power to the wireless device.

Abstract: In general, techniques are described for filter media monitoring within a filtration system. The filter media monitoring techniques described herein include, for example, direct contact with the filter media, e.g., a sensor may be located inside a boundary defined by a surface of the filter media, or indirect contact with the filter media, e.g., a sensor may be located outside the boundary defined by the surface of the filter media such that the sensor does not make direct physical contact with the filter media being monitored.

Abstract: A shoe (606) degradation sensor (1012, 608) assembly includes a first sensor (1002) disposed in or proximate to a material layer of a shoe (606) between a foot space and an outer surface of the shoe (606). The material layer changes in at least one physical property with degradation to the shoe (606), and the first sensor (1002) is configured to indicate the changing physical property of the material layer thereby indicating a degree of degradation to the shoe (606).

Abstract: A radio frequency (RF) sensing device in an assembly is adapted to wirelessly communicate with a remote transceiver. The sensing device includes a substrate; an antenna disposed on the substrate; an electronic circuit disposed on the substrate and electrically coupled to the antenna; a heating element electrically coupled to the electronic circuit for heating a target area; and a sensing element thermally coupled to the heating element for sensing a temperature of the heating element. The RF sensing device is configured to wirelessly receive a power and provides the power to the heating element.

Abstract: At least some aspects of the present disclosure feature an RF device including a conductive loop and a plurality of resonant circuits. Each of the plurality of resonant circuits is electromagnetically coupled to the conductive loop with an effective coupling coefficient. The effective coupling coefficient has a relative low absolute value such that each of the plurality of resonant circuits has a distinctive resonant frequency.

Abstract: In general, techniques are described for filter media monitoring within a filtration system. The filter media monitoring techniques described herein include, for example, direct contact with the filter media, e.g., a sensor may be located inside a boundary defined by a surface of the filter media, or indirect contact with the filter media, e.g., a sensor may be located outside the boundary defined by the surface of the filter media such that the sensor does not make direct physical contact with the filter media being monitored.

Abstract: In general, techniques are described for filter media monitoring within a filtration system. The filter media monitoring techniques described herein include, for example, direct contact with the filter media, e.g., a sensor may be located inside a boundary defined by a surface of the filter media, or indirect contact with the filter media, e.g., a sensor may be located outside the boundary defined by the surface of the filter media such that the sensor does not make direct physical contact with the filter media being monitored.

Abstract: In general, techniques are described for filter media monitoring within a filtration system. The filter media monitoring techniques described herein include, for example, direct contact with the filter media, e.g., a sensor may be located inside a boundary defined by a surface of the filter media, or indirect contact with the filter media, e.g., a sensor may be located outside the boundary defined by the surface of the filter media such that the sensor does not make direct physical contact with the filter media being monitored.