Abstract: An indoor air quality (IAQ) system for sensing and controlling air quality within a structure is provided. The IAQ system includes a plurality of air quality sensor modules configured to sense IAQ parameters and remotely located within the structure. The IAQ system also includes an IAQ control hub including (i) a communication interface communicatively coupling the IAQ control hub to the plurality of air quality sensor modules and (ii) memory holding instructions that cause a processor to receive the IAQ parameters from the plurality of air quality sensor modules and if one of the IAQ parameters is outside a predetermined IAQ parameter range corresponding to the one of the IAQ parameters, request adjustment of control settings of a heating, ventilation, and air conditioning (HVAC) system to shift indoor air quality toward the predetermined IAQ parameter range.

Abstract: Embodiments of the present invention provide for a tamper resistant radon detector monitoring system. Other embodiments may be described and claimed.

Abstract: Embodiments of apparatuses, articles, methods, and systems for measuring sensor drift characteristics are generally described herein. Other embodiments may be described and claimed.

Abstract: Embodiments of the present invention provide for a tamper resistant radon detector monitoring system. Other embodiments may be described and claimed.

Abstract: A plurality of particle size reference values are specified. Data are obtained based at least in part on the specified plurality of particle size reference values.

Abstract: An opto-electric device for measuring the root mean square value of an alternating current voltage has: a) an electric field-to-light-to-voltage converter having 1) a light source; 2) an electro-optic material: (a) receiving light from the light source; (b) modulating said light; and (c) providing a modulated light output; 3) an electric field applied to the electro-optic crystal to modulate the light from the light source to produce the modulated light output; b) an optical receiver for receiving and converting the modulated output light from the electro-optic material to a first voltage that is proportional to a square of the electric field applied to the electro-optic material; c) an averager circuit receiving the first voltage and providing a second voltage that is proportional to the average of said square of said electric field over a period of time; and d) an inverse ratiometric circuit receiving the second voltage from the averager circuit and returning a third voltage that is an inverse voltage of th

Abstract: An opto-electric device for measuring the root mean square value of an alternating current voltage comprises : a) an electric field-to-light-to-voltage converter having 1) a light source; 2) an electro-optic material: (a) receiving light from the light source; (b) modulating said light; and (c) providing a modulated light output; 3) an electric field applied to the electro-optic crystal to modulate the light from the light source to produce the modulated light output; b) an optical receiver for receiving and converting the modulated output light from the electro-optic material to a first voltage that is proportional to a square of the electric field applied to the electro-optic material; c) an averager circuit receiving the first voltage and providing a second voltage that is proportional to the average of said square of said electric field over a period of time; and d) an inverse ratiometric circuit receiving the second voltage from the averager circuit and returning a third voltage that is an inverse voltag

Abstract: An opto-electric device for measuring the root mean square value of an alternating current voltage comprises: a) an electric field-to-light-to-voltage converter having 1) a light source; 2) an electro-optic material: (a) receiving light from the light source; (b) modulating said light; and (c) providing a modulated light output; 3) an electric field applied to the electro-optic crystal to modulate the light from the light source to produce the modulated light output; b) an optical receiver for receiving and converting the modulated output light from the electro-optic material to a first voltage that is proportional to a square of the electric field applied to the electro-optic material; c) an averager circuit receiving the first voltage and providing a second voltage that is proportional to the average of said square of said electric field over a period of time; and d) an inverse ratiometric circuit receiving the second voltage from the averager circuit and returning a third voltage that is an inverse voltage

Abstract: The crest value and RMS value of a signal are measured. The ratio of the two values, the crest factor, is calculated to provide a measure of the signal wave shape. The frequency range and accuracy of a commercially available RMS converter is improved by providing an improved rectifier ahead of the converter's internal rectifier. This improved rectifier is also used to form the absolute value of the input signal. A peak detector then provides the crest value (absolute peak value). The crest value and RMS value are multiplexed to a computer having an A/D converter. The RMS value, crest value and crest factor can be calculated and displayed and/or stored by the computer.

Abstract: The frequency range and accuracy of a commercially available RMS converter is improved by providing an improved rectifier ahead of the converter's internal rectifier. The improved rectifier switches between the input signal and an inverted version of the input signal in response to a high speed comparator. The improved rectifier can also incorporate range selecting circuitry.