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Index
Introduction
Data
Acquisition
Methodology
Spatial
Analysis
Operational
Errors & Problems
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Operational
Errors & Problems:
Data Discarded:
The reservoirs shape file was discarded from the dataset because after clipping the shape file with County.shp, there was no data point within Fulton County. To save space, the associated files were deleted.
Operational errors:
- The
project was assumed that weather is clam (stationary).
No wind will carry airborne pollution away from the source.
- There
is no elevation element in the dataset.
This constrain the fact that river water carry liquid pollutant
away from the source. There
was not any data for elevation because the only free available DEM
data was in 1:12,000. This
was not matching other themes’ scales.
- The
pollutant discharge from varies source are assumed to be constant in
quantity and rate. In
fact, discharge rate and amount are varying throughout the entire
operation.
- The
final analysis is based on three classes.
The classes are equally ranged.
More classes with appropriate ranges can lead to more accurate
estimation. In real life,
damage can be done even with small concentration of substance.
Toxic chemical, for example, can genetically modify a spice’s
DNA with some dose of radiation.
Problems:
- Disc
space is a major problem during the evolution of this project.
The initial data take up to 100 mb.
After transferring all data into raster format, the data size
increased to 300mb. This
had reach the Vine’s account limit.
It is unsafe to delete all dataset from ArcView format after
converted all image to raster format.
The ArcView formatted data may be needed further down in the
project. The alterative backup method is to copy everything onto
a CD-RW. One CD can
subject to lost data, and lost disc.
This method is not safe as well.
- Finding
out the method to project data into proper projection was not
straightforward. The
original data are in Lambert
Conic Conformal. Idrisi do not have Lambert Conic Conformal. Every theme must re-project to NAD 1983 StatePlane West Georgia State FIPS 1002 which
Idrisi support. This
is especially difficult with Idrisi.
This is because Idrisi arrange its coordinate system in code.
The code are only written in Idrisi manual not the help file.
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