Ground-truthing

We will be using color-based object recognition to evaluate the quality of the color constancy algorithms. Where ground truth data is available, we can also compare the output of the different algorithms to the measured ground truth data. 

Table 13.13 Comparison to ground truth data for image sets 1 through 5.

What kinds of instruments are going to be used for conducting the so-called ground-truth and remote-sensing measurements ... 

Abstract Seawater concentrations of the climatecooling, volatile sulphur compound dimethylsulphide (DMS) are the result of numerous production and consumption processes within the marine ecosystem. Due to this complex nature, it is difficult to predict temporal and geographical distribution patterns of DMS concentrations and the inclusion of DMS into global ocean climate models has only been attempted recently. Comparisons between individual model predictions, and ground-truthing exercises revealed that information on the functional... 

Prior to carrying out ground-truth studies, a more quantitative understanding of several aspects of the CS sediment slurry delivery system was needed. Of major importance was the need to know, as precisely as possible, as many aspects as possible of the sediment slurry from the time it enters the sea-floor-sled pumping means to its extraction at the shipboard sample processor. 

After the testing and evaluation of the operational parameters of the sediment retrieval system, the ground-truth study of the CS system was initiated to determine whether the CS samples reflected the true sediment composition and, therefore, its ability to correctly and rapidly survey the seafloor sediment. 

The final phase in the development of the CS system was to test and evaluate the capability of the CS system to analytically portray the true elemental content of the seafloor sediments. To carry out this task, a joint Center for Applied Isotope Studies (CAIS)-NOAA ground-truth study was initiated. A site for the study was selected in the Baltimore Harbor (Maryland) along the Patapsco River, south of North Point and adjacent to the Brewer-ton Channel see Figure 7 ). This site is a discontinued spoil area with documented high levels of heavy metals in the sediments. Water depths of this site are 15-25 m, well within the operational range of the CS system, and it is located close to available NO A A facilities. 

The ground-truth sediment sampling program was carried out by... 

Sediment sampling of the seven stations using the CS equipment was carried out by running transects with the survey vessel parallel to, and as close as possible to, the marker buoys. The CS underwater seafloor sediment sampler was pulled at a speed of three knots and, when abreast of each buoy, the sediment collected was recorded as being from that station. The sediment wafers prepared aboard ship from the collected slurries were immediately analyzed by XRF for three elements (Mn, Fe, and Ti) and were stored for further land-based analyses of other elements. A comparison of the elemental content of the sediments collected from the seven stations by box coring and with the use of the CS equipment constituted the basis for ground-truth evaluation of the CS system. 

Table IV shows good agreement between the CS heavy metals values and the ground-truth data shown in Tables I and II. With the exception of Pb, all the elements were determined with good accuracy and indicated a ground-truth agreement between the surficial sediments and the CS wafers produced from the same material. The XRF analysis made use of six different standards that were compared to NBS standard reference material 1646. This standard is a marine sediment of nearly identical mineral composition to that of the Baltimore Harbor samples.

Table V. Ground-Truth Comparative Elemental Analysis of Baltimore Harbor Surficial...

Lpplications of continuous, underway measurement to marine science include measurements of chemical variability in the upper ocean, especially near coastal fronts and streamers (i, 2) determination of the in situ concentrations of trace metals (3) and of dissolved gases near the air-sea interface 4, 5) assessment of the types, concentrations, and variations of planktonic communities (6) investigation of the mixing and lateral dispersion of pollutants in the sea (7) and the acquisition bf spatially adequate ground truth for remote sensing of fisheries stocks and oceanic prop-... 

Schiewer, U.,1994. Makrophytenkaitierung und Ground-Truth-Messungen in der DarB-Zingster Boddenkette, Juli-August 1994. Final Report to the German Ministry for Education and Science, Rostock. 

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