Testing and Evaluation of Standoff Chemical Agent Detectors (2003) / Chapter Skim
Currently Skimming:
3 Recommended Test Protocol and Decision Tree for Passive Detectors
3 Recommended Test Protocol and Decision Tree for Passive Detectors
Pages 12-18
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 12... ...
The major flaw in the protocol is the lack of information about the highly variable backgrounds that will be observed in the field. The background for chamber tests is an extended blackbody source of known temperature, whereas the background for field measurements is likely to be highly variable and could include forests, hillsides, sky, grasslands, lakes, etc., for which the emissivity will not only be less than 1 but will almost certainly vary across the spectrum.
|
From page 13... ...
The spectral data obtained in this way can be used with the acquired field background spectra to synthesize spectra that would be observed under field conditions with said simulants, concomitants, interferents, and agents present. The simulation of spectra over a range of temperature differentials will · ~ ~ ~ r ,~ · , ~ ~ at, , r ,~ ~ · ~ ~~ · ~ require knowledge ot the approximate background temperature ot the scene being used.
|
From page 14... ...
under field conditions so that a wide range of CL products and /\Ts are included, where C is the concentration of the sample (ppm) , L is the effective path length (m)
|
From page 16... ...
6. Acquire passive spectra of simulants and interferents in a chamber with a blackbody source to validate the model developed in Steps 4 and 5 using the same type of instrument used to collect the background spectra operated at the same resolutions used in the field.
|
From page 17... ...
Successful performance through all subsequent decision nodes indicates that the instrument will provide field detection of CWAs with the expected false positive/false negative rates in the field conditions as defined in Step 5. As will be 150perational Requirements Document (JORD)
|
From page 18... ...
18 TESTING AND EVALUATION OF STANDOFF CHEMICAL AGENT DETECTORS subsequently discussed under the risk assessment (Chapter 7 and Appendix C) , it needs to be recognized that the essentially infinite array of field conditions will likely cause some deterioration of instrument performance against the metrics used in testing, and there is no practical way of estimating this deterioration beyond the background testing that has been included in the signal-processing model, short of adding even more background spectra to the model.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.