A humidity detection device includes a humidity sensor, a resistor connected to one-side of the humidity sensor, a first switching part connected to the resistor; a diode connected to the first switching part; a second switching part connected to the other-side of the humidity sensor, a potential difference generating part connected to the second switching part, a power supply supplying a voltage, and a control part applying the voltage as an alternating voltage to the humidity sensor by controlling the first switching part and the second switching part. The control part applies a current to the diode, the resistor and the humidity sensor in a first direction by connecting the second switching part to the ground, and applies the current to the resistor and the humidity sensor in a second direction, which is an opposite direction from the first direction, by connecting the first switching part to the ground.

A detection system includes at least one sensor configured to measure a presence of airborne particles and at least one amplifier circuit in communication with the at least one sensor. The amplifier circuit is configured to monitor a charge generated by the at least one sensor over a time interval. The system further includes a controller configured to monitor the charge accumulated in the at least one amplifier circuit from the at least one sensor at the time interval. In response to the charge of the at least one amplifier circuit, the controller detects the presence of the airborne particles.

A humidity sensor is provided with a first electrode electrically connected to a first terminal, and a moisture-sensitive member. The first electrode may include a first internal electrode unit. The first internal electrode unit may include a first main surface covered with the moisture-sensitive member, and a second main surface covered with the moisture-sensitive member. The humidity sensor may further include a second electrode electrically connected to the second terminal. The second electrode may include a second internal electrode unit. The second internal electrode unit may include a third main surface covered with the moisture-sensitive member, and a fourth main surface covered with the moisture-sensitive member. The first internal electrode unit may include a portion facing at least a part of the second internal electrode unit across the moisture-sensitive member.

The techniques relate to methods and apparatus for determining data indicative of a concentration of an analyte in a fluid. First data indicative of a first property measurement of a first sensor while in fluid communication with the fluid is accessed. Second data indicative of a second property measurement of a second sensor in fluid communication with the fluid is accessed. A set of one or more parameters related to the first sensor, the second sensor, or both are accessed. The data indicative of the concentration of the analyte in the fluid is determined based on the first property measurement, the second property measurement, and the set of one or more parameters.

Gas detection performance is enhanced with a configuration that does not need an air current generating device. In a gas sensor, three or more gas sensor elements are arranged such that two or more gas sensor elements have substantially the same gas response characteristic, and a first phantom line connecting two of the elements intersects an element except for the elements forming the first phantom line or intersects at least one second phantom line formed by elements except for the elements forming the first phantom line.

An apparatus for measuring a concentration of a target gas includes: a gas sensor including a sensing layer having an electric resistance that changes by an oxidation reaction or a reduction reaction between gas molecules and the sensing layer; and a processor configured to, in response to the target gas being introduced along with air into the gas sensor, monitor a change of the electric resistance of the sensing layer and determine the concentration of the target gas by analyzing a shape of the change of the electric resistance.

A sensing device includes a first substrate having a plurality of TSVs extending therethrough, and a second substrate positioned adjacent the first substrate, with the TSVs being electrically connected to the second substrate. At least one carbon nanotube sensor is positioned on the first substrate. Each of a plurality of contact pads is positioned on the first substrate and on one of the carbon nanotube sensors such that each contact pad is electrically connected to one of the TSVs and the one of the carbon nanotube sensors, and such that an end of the one of the carbon nanotube sensors is embedded in the contact pad.

An organic liquid sensor configured to output a signal corresponding to the presence of one or more organic liquids is provided. The sensor includes a circuit board, a sensor film deposited on the circuit board, the sensor film including a first length, a second length, and a bridge portion, the first length and the second length being electrically separated by a gap and the bridge portion being electrically coupled to the first length and the second length. The circuit board is configured to detect a resistance of the sensor film.

A detector is provided including a plurality of nanofiber chemical sensors, each having an electrical characteristic; and a processing and alarm circuit in electrical communication with the plurality of nanofiber chemical sensors; wherein the electrical characteristics of at least one of the plurality of nanofiber chemical sensors changes in the presence of a first airborne material; wherein the electrical characteristics of at least one of the plurality of nanofiber chemical sensors changes in the presence of a second airborne material; and wherein the changes in the electrical characteristics of at least one of the plurality of nanofiber chemical sensors in the presence of the first airborne material are different from the changes in the electrical characteristics of at least one of the plurality of nanofiber chemical sensors in the presence of the second airborne material.

A meter includes prongs that detect the moisture content value of a tobacco product, and an electrical circuit of the meter receives this information and converts the moisture content value to a relative humidity value of the tobacco product. The relative humidity value is displayed as a numeral on a display sensor connected to the electrical circuit.