portfolio

Here you can see one of my
individual exercise for ArcGIS
course that I persued during my
bachelor in Politecnico di Milano.
I explained in details with 8 steps
from the beginning and
mentioning the main extension
for each step since the course and
exercise was in Italian, here I tried
to summerise it and change the
text to english.
Main criteria to identify high risk
areas:
A) Areas with the slope between 28
and 55 degrees and minimum
extension of 625 square meters.
B) Land Cover: higher risk in the
case of the pasture lands.
AVALANCHE RISK ANALYZES IN PEJO VALLEY IN TERENTINO
“Spatial Analyzes” extension for managing raster datas.
1. Creation a digital terrain
model (DTM) by converting
the text file into a shape file
and classification it respect
to hight of points, “ALT_QT”.
2. Rasterization of points
using the “IDW” extenstion (
Interpolates a surface from
points using an inverse
distance weighted technique).
3. Slopes’ map extraction
and introducing tre categories
of themrespect to their
degrees;
- Less than 28 (green).
- Between 28 and 55
(yellow).
- Higher than 55 (red).
This exercise is an attempt to
design a Territorial Information
System in order to show different
services with available public
transports to reach each of them,
identifying the number of
bus/tram with its time schedule, in
addition available car parks in an
area around Politecnico di Milano.
The primary aim was to get
familiar with how to structure
Topographic DataBase (DBT) and
consequently manage them in a
effective and practical way.
the goal is to show the
accessibility of services around
the Polytechnic, in such a way that
choosing a specific service,
Territorial Information System will
show the path associated with that
service, any eventual public
transports and existing car parks.
ACCESSIBILITY OF SERVICES AROUND POLITECNICO
Unification of two tables of
"services" with “paths” in order to
create the relation 1:1 between
them, by using “Join” extension, in
such a way that choosing one path,
TIS will show the services that exist
around it and viceversa,
later, a query is performed on Paths’
shapefile, choosing Supermarkets
(in this project: Carefour) as the
Typology to be selected. TIS will show
which paths can be taken to reach it.
c) Slope exposure: SouthEst, in the
summertime and Nord in winter.
The high risk areas will be areas in
which the subject of A, B and C
cases intersect each other.
Datas given by exercise:
1- ptiqt_virgola.txt, in text format,
it contains the points generated by
contour lines’ nodes which has
been obtained from digitization of
the CTR 1:1000 in Val di Pejo (North
Western Trentino), area with high
frequency of avalanches.
The reference system is Roma40
with Gauss-Boaga projection.
2- cveg.shp, Cultivation classes
shapefile.
3- val_08.shp, areas that had
avalanche in 2008.
4- val_08.shp, orthophotos.
Orthophotos 42010
High risk areas in summer
High risk areas in winter
Intersection of critical slopes with the land cover
Avalanche observed by the Photo_Interpretation methods
4. Identification of the
slopes between 28 and 55
as the critical ones ( green
colour) by using “Raster
Calculator”.
7.1. Comparison the result
with the map of avalanches
given in exercise.
“Spatial Analysis Tool” is
the main extension in this
step.
8.1. Rasterization of the
map obtained in the previous
step (the map of conditions
A and B), afterwards
multiplying it with the map
of critical areas in Sud_Est
which will be the map of the
critical areas in summer
(estate).
5. Identification of the
areas with slopes between
28 and 55 degrees and with
extention higher than 625
square meters (exercize’s
point A), by using “conversion
Tools”.
7.2. Map of extensions.
8.2. Attainment of the map
of critical areas in winter
(inverno) with the same
metod used for the summer
(estate).
6. Openning the land cover
map (cultivation class) and
selecting the areas cultivated
with pastures
through a standard quary (
dark colour, subject of the
point A and B).
“Geoprocessing” and
“Intersect” are the main
tool for this step.
7.3. reclassification of the
previous map introducing
South_east equal to 1 and
the rest equal to 0.
8.3. Final global risk map
which will be drawn from
the sum of the two summer
(estate) and winter (inverno)
maps.
The database allows the
topographical structure of spatial
information layers and classes
topologically linked to one
another, such interaction should
guarantee the complete digital
view of
the ground.
Entity Attribution Primary Key
Services
Paths
Public
Transport
Stops
Car Parks
-Shape
- Nome
- Address
- Typology
- Opening Hours
- Closing Hours
- Politecnico’s Entry
- Entrance Code
- Type of Sport
- Shape
- Politecnico’s
Entrance Code
- Typology
- Lenght
- Shape
- Typology
- ID Public Transport
- Timetable
- Shape
- Address
- Area
- Typology
ID services
ID paths
ID stops
ID car parks
Differential correction and export
to shape file by Mobile Mapper
Office which permits to increase
the precision performing a relative
positioning with respect to a
permanent station connected to
the Internet. Lombardy Region
disposes a network of stations
accessible to public, the station on
Nave building (Bonardi Street,
Politacnico) was chosen because
of its nearness to the area of relief.
Later, transforming the shapefile
into another reference system
(from WGS84 into
Gauss_Boaga/Roma40) by using
VertoGis software make the
outcome now utilizable in ArcGIS.
Relation 1:N
Relation 1:1
Relation N:M
Relation 1:N
Entity-Relationship Diagram (ERD) designed by "RISE Editor" program
There is at least one path that is
connected to one or more stops
It is possible that there is a path with
no corresponding stop
Relationt 1: N between two tables is
determined by the extension
"relate".
Relate’s operation is not visible by
checking fields in a table as Join’s
operation.
however, once you make a 1:N
relation between two tables and
query datas, you can see also the
fields of the table put in relation
with.
Here the “Relate” applied between
"paths" and "stops" tables is to
make this relation in suche a way
that choosing a path, through the
extension "relate", we would be able
to see the stops that are connected
to that specific path.
Finally, it is possible to visualize the departure and arrival time of each associated public transport. To do this,
an additional field has been added to the table of "fermate" (stops) containing links saved on the same folder in
which the GIS file of work is saved. So clicking on one stop the time table associated to it will be rendered and
appeared.