Appendix D Acronyms and Glossary of Terms
Active Detectors:
detectors that create an optical signal by probing a scene with a light source (i.e., a laser); lidar is an example of such a detector.
Aerosol:
small solid particles or droplets suspended in a gas or vapor.
Albedo:
the ratio of light scattering to the sum of absorption plus scattering.
Artemis:
a CWA standoff detection system designed to augment existing CWA detection systems to provide a theater-wide capability of near real-time detection and warning.
Blackbody:
an object that completely absorbs incident radiation of all wavelengths and emits radiation according to Planck’s law.
BMI:
Battelle Memorial Institute.
CBDP:
Chemical and Biological Defense Program.
Chemometrics:
the application of any of a variety of multivariate algorithms to data from chemical instruments to perform qualitative or quantitative analysis.
Concomitants:
compounds that may be present under battlefield conditions—such as adhesives, thickeners, and propellants—whose spectra may interfere with detection of target chemicals.
CWA:
chemical warfare agent.
DIAL:
differential absorption lidar—lidar technique based on transmitting at least two wavelengths of light that are absorbed to different degrees by the target gas.
DoD:
Department of Defense.
DTRA:
Defense Threat Reduction Agency—a department within the DoD.
DUSA-OR:
deputy under secretary of the army for operations research
FOV:
Field of view—angular breadth that can be imaged by the system (radians).
Ground truth:
measurement that allows a particular parameter to be accurately known.
Henry’s law:
the pressure of a gas above a solution is proportional to the concentration of the gas in solution.
Interferents:
chemicals that in some way interfere with the detection of target chemicals; this interference can be spectral (spectral signals that are similar to the target chemical), chemical (materials that react in the atmosphere with the target chemical), or physical (materials that change the physical form of the target chemical by precipitation, adsorption, etc.).
JSLSCAD:
Joint Service Lightweight Standoff Chemical Agent Detector.
Lidar:
light detection and ranging—an active detection technique using a laser-like beam as the transmitter.
M21 RSCAAL:
Remote Sensing Chemical Agent Alarm.
MCAD:
Man-portable Chemical Agent Detector.
Mie scattering:
scattering of radiation by solid particles or liquid droplets the diameters of which are approximately equal to the wavelength of the radiation.
Neural network:
a calibration algorithm based on the concept of connectivity of modes. By constructing all possible connections between nodes, all possible relationships between input data and the final desired results can be explored.
NRC:
National Research Council.
ORD:
Operational Requirements Document.
Passive detector:
detectors that require no action on the part of the operator to generate the analytical signal.
Simulant:
a molecule having either spectroscopic or physical properties similar to the corresponding properties of a CWA.