Lecture Materials, UP402
(as a supplement to, not
a replacement for, in-class material.)
Week 1--Coordinate Systems
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Introductions; project interests.
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Website and syllabus
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Biosketches: include background project interests.
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Latitude and Longitude
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chalkboard explanation
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link
to brief explanatory material
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GIS maps
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Lab--set up website, discuss project interests.
Week 2--Coloring
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Coloring of maps;
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Choropleth maps; Color; Grayscale; Four Color Theorem (choosing
numbers of colors)
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Given that no more than four colors are ever needed to color a map in
the plane, why should a GIS have so many choices for color?
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Choropleth maps with many ranges need a variety of colors
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Ranges need to make sense so that changes in data intensity are reflected
in changes in color intensity
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Grayscale and color, this parallelism about data and color intensity
is critical
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Four colors are sufficient to color any map in the plane; one never
needs more than four. Thus, when choosing coloring schemes, bear
this fact in mind and have a rationale for color selection based on the
underlying known theorem about coloring. One such good rationale
is offered above, involving choropleth maps.
Open research questions: coloring issues with different forms
of polygon adjacency; coloring on different surfaces (some solved earlier--extra
reading: Page
4. Page
5. Page 6.Page
7. Six
color map; link
to site with movie of seven color map). We may return to these later
when we discuss map transformations of various sorts.
Lab: websites and projects
Week 3--Applications
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Tie to lecture from last week: Möbius strip map in the world
of art: David Barr's Four Corners Project.
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The problem: lop four corners off a tetrahedron and use as the
four corners of a tetrahedron inscribed in the Earth (with all corners
on land).
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The field work
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The map
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The extended problems
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Tie to setting up projects and the acquisition of initial information:
The international scene: Syria and Pakistan. (From the CSF
website archive.)
Week 4--Ties to previous topics
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A fundamental geographical problem: Scale
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Animated Maps--samples. Animation integrates space and time.
Week 5--More Ties to previous topics...
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How can you tell the inside from the outside--(the
Mobius strip was a one-sided surface...) Jordan Curve Theorem; implications
for mapping.
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The Jordan Curve Theorem:
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permits correct assignment of addresses on either
side of streets--suppose that the path is composed of two squares touching
at a point. When the path is separated into two squares, a consistent
assignment procedure for addressing may be given. If the squares
were not split apart, then the set of addresses would be misallocated,
at least in part. One must have the Jordan Curve Theorem built into
the software if geocoding is to work on matched addresses.
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permits visually appropriate coloring of polygons
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illustrates the need to split complex curves apart
at nodes where the curve crosses itself in order to ensure that the two
properties above will hold on maps. This fact is important in digitizing
(and elsewhere).
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Defining regions in the absence of regional information: making
something from nothing--as in the case last week with the surrogate variable
of 1995 data to mimick migration patterns? (All three cases below
use ESRI software, ArcView3.2 with Spatial Analyst Extension, 3D Analyst
Extension; also Animal Movement extension from the Alaska Biological Center,
and Xtools from Oregon Forestry).
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Spider
diagrams: one way of defining regions in the absence of regional
information.
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Thiessen
polygons: another way of defining regions in the absence of regional
information
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Contours:
Partitioning the plane in various ways (level curves of a surface--but
hard to find--requires knowing an equation for the volume).
Other ways, we have seen, to make maps come alive: animation--brings
temporal and spatial elements together. Use of Adobe ImageReady.
Week 6. Getting information into usable form.
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ArcView comes with an onboard information systems: base maps and
databases.
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Transform other situations to the one above:
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Bring in new data
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work in Excel, save the file as a .dbf, use the "join" feature in ArcView
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work in ArcView, add a field or more, use the "field calculator"
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Bring in new maps--scan them; digitize them from scanned images.
Put information in a "new theme" and remember to update the area...
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Point data
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drawing points in a new layer: useful for updating files or adding
a small amount of information--optimizes user control
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adding points as an Event Theme: useful for creating new files
from gps data or web data with large numbers of points--computer benefit
optimized
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Line data
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find contours elsewhere (as in Digital Chart of the World or elsewhere)
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digitize contours: sample.
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Areas
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finding files elsewhere (as from the U.S. Bureau of the Census)
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digitizing regions: sample
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splitting polygons
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adjacent polygons
Fall Study Break, Monday and Tuesday, Oct. 13 and 14. I will
be in my office all day for office hours (on Monday). Class as usual
on Wednesday, October 15.
Week 7. Trouble shooting...
1. ArcView
a. Set working directory
b. Convert files to shape files if they
do not come as shape files
c. Save the .apr file to the working directory
d. Move all the files in the working directory.
The .apr file is a template that reaches for the shape files and the associated
indexing and datbase files. The .apr file saves the colors and so
forth. If you run the .apr file on a path different from the one
you created it in, you will have to "locate" the .shp files and the .dbf
files with the new path, as prompted when trying to load the .apr file.
(More advanced users can use Notepad to open the .apr and use search and
replace to alter the path quickly.)
2. Webpages
a. Be sure to upload images along with
pages
b. Check pages on both networked and stand
alone computers
c. If images don't show, check path and
check spelling (upper/lower case)
3. PhotoShop
a. transparency
b. layers
Week 8. No Quiz; party afterwards at Sandy's home.
Midterm Presentations:
salinay, Daniel Slosberg
hharriet, Harriet Hamilton
ppolansk, Paul Polanski
spschult, Steve Schultz
szukaiti, Scott Szukaitis
waltona, Andrew Walton
mbunce, Melanie Bunce
adgreen, Elly Green
racheleg, Rachel Green
smichejd, Steve Michejda
ncrobins, Nicole Robinson
carowest, Carolyn Westbrooks
whiner, Stephanie Givinsky
lroumell, Loren Roumell
schwarmi, Michael Schwartz
looseg, Geoffrey Loose
ebeckett, Eric Beckett
Weeks 9 and 10.
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Map projection: the goal is to send
each point on the globe-sphere to a unique point in the plane: a
one-to-one transformation.
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Stereographic projection--trapped in Euclidean geometry.
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The One-point Compactification Theorem (blackboard
demonstration): shows that the skin of a spherical globe cannot be perfectly
flattened into the plane; it fails to do so by at least one point. Thus,
there can be no perfect map in the plane: the stated goal cannot
be attained.
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Open questions: geographic maps in the non-Euclidean
world.
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Map projection as a transformation: Thompson's
fish--classification schemes are not unique, either. There is
an infinite number of them (Tobler, Map Transformations of Geographic Space).
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Color, extrusion, and use of GIS to move from 2D to 3D.
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check to see that both the Spatial Analyst and 3D Analyst extensions are
enabled
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Go to View|3DScene|Themes
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Go to Theme|3DProperties
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In the extrude section, hit the calculator button and choose "height"
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Go back to the extrude section and multiply "height"*5, to exaggerate the
vertical component--or click on "vertical exaggeration" in the "properties"
menu.
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Use the various buttons to move the Scene around--rotate it, zoom in and
out: left-click and drag--rotate; right-click and drag--zoom in and
out; both-click and drag--pan.
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Export to vrml and put on a website: load Netscape plug-in to view--free
from, http://www.cai.com/cosmo/html/win95nt.htm
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and also look at a website from
UM College of Engineering Virtual Reality Lab to see other projects and
student projects from Eng 477 (Prof. Peter Beier).
Real-world application--project making alternative scenarios for City of
Ann Arbor regarding maximum height in the downtown.
Weeks 11 and 12.
Week 13. No class, Thanksgiving recess begins at 5:00p.m.
Week 14.
Week 15. Final Presentations
salinay, Daniel Slosberg
hharriet, Harriet Hamilton
ppolansk, Paul Polanski
spschult, Steve Schultz
szukaiti, Scott Szukaitis
waltona, Andrew Walton
mbunce, Melanie Bunce
adgreen, Elly Green
racheleg, Rachel Green
smichejd, Steve Michejda
ncrobins, Nicole Robinson
carowest, Carolyn Westbrooks
whiner, Stephanie Givinsky
lroumell, Loren Roumell
schwarmi, Michael Schwartz
[looseg, Geoffrey Loose]
ebeckett, Eric Beckett
Week 16. Final Projects Due as Website; turn in URL via
e-mail no later than 5:00 p.m. Party at 6:00p.m. at Sandy's home.