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.

A system for testing alcohol breath analyzers, wherein the system comprises an alcohol breath gas generation device, a test chamber, a reference measuring device, a control and registration unit, and a distribution unit. The invention also relates to methods of testing alcohol breath analyzers.

A system is provided that detects the odor of air exhaled from a subject. Based on affection information and the odor, the system indicates features of the exhaled air related to a disease based on measurement information in which the affection information indicates affection or non-affection. The system also detects the odor in the air from a medical examinee. Based on the measurement information and the features, the system determines the possibility that the medical examinee will be affected with a disease.

Disclosed is a method for calibrating a sensor to be calibrated by means of a reference sensor, the sensor to be calibrated being configured to determine a chemical signal based on a conversion function for converting an electrical signal, the reference sensor being configured to determine a reference signal, the method having: ⋅ measuring, during a reference time period, a first chemical signal (S1P1) and a first reference signal (S2P1) and, during a test period, a second chemical signal (S1P2) and a second reference signal (S2P2), determining regression functions (gP1, gP2) defined as follows: S2P1=gP1(S1P1) and S2P2=gP2(S2P2), calculating a difference between the regression functions (gP1, gP2) and ⋅ when the difference is greater than a reference difference, determining an optimized conversion function.

A gas sensing element that reflects light incoming along an optical path on a sensing face, where the light reflected by the gas sensing element changes depending on a quantity of a specific gas that is in contact with the gas sensing element, and where each of a first optical fiber and a second optical fiber bends the optical path. The gas sensing element, a light source, a photodetector, and a magnetic field applicator are disposed on a same side with respect to a virtual plane that is perpendicular to an incident plane of the incoming light to the sensing face of the gas sensing element and includes a point on the optical path where light goes out from the first optical fiber and a point on the optical path where light enters the second optical fiber.

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.

Methods and systems for determining water status in plant tissue are provided. A number of systems are capable of using terahertz signals to generate signals measuring total water content in plant tissue, including plant leaves. Using these signals, methods are capable of determining water status variables, including water mass per leaf area, relative water content, and leaf water potential, which can aid in agricultural, ecological, and environmental health, such as dehydration and droughst stress of plants.

Provided is a capacitive gas sensor. The capacitive gas sensor comprises a sensitive material for adsorbing and desorbing a target gas, an upper electrode surrounding the sensitive material, a lower electrode facing the upper electrode, and a porous structure disposed between the upper electrode and the lower electrode, wherein the capacitance of the sensitive material changes as the sensitive material adsorbs and desorbs the target gas.

Computer systems, methods, and apparatuses for estimating changes in gas emissions are described. A computer system may monitor overall emission levels based on sensor outputs from a plurality of gas sensors in a facility. The computer system may estimate a total emission level over a time interval based on the accumulative, gas-response-factor weighted detections of the gas sensors. Emissions from maintenance activities may be excluded as appropriate. The total emission level may be compared with total emission level estimated from different time intervals and/or different facilities. The computer system may be further used for comparing emissions across multiple facilities, or emissions from facilities across multiple regions.

The present invention provides method for monitoring physiological status of an organ in a subject by monitoring morphological changes over time in transplanted tissue on an eye of the subject.