An apparatus for controlling blending of a gas mixture containing known components, including first, second, and third control valves for controlling the flow of first, second, and third components, respectively, a first gas density sensor to measure the density of a first mixture of the first and second components, a second gas density sensor to measure the density of a second mixture of the first mixture and the third component, and a controller to determine based on data from the first and second gas density sensors the relative compositions of the first, second, and third components in the second mixture, and to control the first, second, and third control valves to obtain a desired relative composition of the first, second, and third components in the second mixture.

Object: To provide a remote substance identification device that can identify an unidentified substance, such as a harmful substance, from a remote location. Solution: Provided are a remote substance identification device and method, the device comprising a laser device 10 that emits a laser beam to an irradiated space; a wavelength conversion device 20 that converts a wavelength of the laser beam emitted from the laser device into a plurality of different wavelengths and that emits laser beams of the different wavelengths to the irradiated space; a light collecting-detecting device 30, 40, 50 that collects and detects resonance Raman-scattered light generated from an irradiated object due to resonance Raman scattering; and a processor 60 that identifies the irradiated object on the basis of a result detected by the collecting-detecting device 30, 40, 50.

A system for monitoring FFUs in each of clean rooms includes a first exhaust fan disposed above the clean rooms; lines each having one end connected to the FFUs in each clean room and the other end connected to a gateway; a personal computer communicating with the gateway; gas removal units disposed under the clean rooms and connected to a second exhaust fan; an emergency damper connected to the second exhaust fan; a CO.sub.2 cylinders room disposed besides the emergency damper; and gas detectors, each communicating with the FFUs via the line, each gas detector having a connector connected to the gateway.

Disclosed herein is a dust measuring apparatus and method for measuring a dust concentration in a flow channel. The apparatus includes a flow channel unit for defining a flow channel allowing a fluid containing dust to move therethrough, a light emitter for emitting light into the flow channel, a light detector for detecting light scattered from the dust in the flow channel and converting it to an electrical detection signal, the light detector including a plurality of detectors having different light detection ranges, and a controller for controlling the flow channel unit, the light emitter and the light detector, wherein the controller is configured to receive detection signals from the detectors, compensate for an offset for the received detection signals, and measure a dust concentration based on the compensated detection signals.

Devices and techniques related to landfill gas extraction are disclosed. A technique for controlling extraction of landfill gas from a landfill through a gas extraction system is described. The method may include measuring a plurality of values indicating conditions associated with the landfill; computing, based at least in part on the plurality of values and on a model of the landfill, a predicted future state of the landfill; determining, based at least in part on the predicted future state of the landfill, one or more control parameters for one or more respective control devices configured to control operation of the gas extraction system; applying the one or more control parameters to the one or more respective control, and with the one or more control devices, controlling extraction of the landfill gas from the landfill based, at least in part, on the one or more respective control parameters.

Disclosed are methods for measuring building health index using some mandatory and set of optionally configured parameters and utilizing building monitoring system having a connection to sensors in or pertaining to a building, and including central computing environment and one or more display devices showing the measurement. A building utilizing this method may be installed with one or more sensors, and which may be communicating to a locally installed communication device or a centrally installed computing environment that can collect the measurements over a period.

The invention relates to a method for determination of ambient mineral dust concentration based on optical absorption of particles concentrated by a virtual impactor as well as a device performing the said method. The method comprises the following steps: Sampling air samples with particle size smaller than 1 μm (PM.sub.1) and sampling air samples with particle size up to 10 μm; Concentrating the samples with particle sizes up to 10 μm with a virtual impactor; Measuring optical absorption of collected samples at least one wavelength from UV to IR spectre, preferably from 370 to 950 nm, most preferably at 370 nm; Subtracting the absorption of the samples with particle size smaller than 1 μm from the absorption of the sample concentrated by the virtual impactor.

A fixed wing drone comprises an air channel embedded therein. The air channel has an upstream an air inlet. A microcontroller mounted within the drone is configured to control navigation of the drone. An air scoop having a section positioned adjacent the inlet to the air channel is adjustable between a first position to capture and divert air into the inlet and thereby to air channel and a second position to block air flow into the air inlet. The air scoop is positioned to divert air flow into the air channel and to the gas sensor during forward flight of the drone. In one embodiment, the fixed wing drone comprises an aircraft having a fuselage and at least two wings. In another embodiment, the fixed wing drone has a flying wing construction, that is, is a tailless design.

Chalcogenide waveguides with high width-to-height aspect ratios and a smooth exposed surfaces can serve as mid-infrared evanescent-absorption-based sensors for detecting and identifying volatile organic compounds and/or determining their concentration, optionally in real-time. The waveguide sensors may be manufactured using a modified sputtering process in which the sputtering target and waveguide substrate are titled and/or laterally offset relative to each other and the substrate is continuously rotated.

An odor detection device (1) includes an odor sensor (10), environmental information measurement means (11, 12), odor information collection means (20), difference information acquisition means (21), and correction means (22). The odor sensor (10) detects information on an odor emitted from an odor source (2). The environmental information measurement means (11, 12) measures information on an environment, correlated with the amount of water vapor contained in surrounding gas. The difference information acquisition means (21) acquires the difference amount of water vapor, indicating a difference between information on an environment surrounding the odor sensor (10) and information on an environment surrounding the odor source (2). The correction means (22) corrects information on an odor, collected by the odor information collection means (20), on the basis of difference information acquired by the difference information acquisition means (21).