DATA AQUISITION

BASE DATA SET

I was able to acquire most of my New York City data from the ESRI tutorial website.  The nice feature of this website is that it allows you to download complete data sets, which are usually related to each other through a theme.  This particular data set was used to illustrate health care in New York.  The data was intended to be used in ArcView, and was in ShapeFile format.  To be used in IDRISI 32 it had to be converted into raster.  In the conversion from vector to raster, all attributes were lost except for the feature identifiers.  The attributes then had to be linked through exporting .avl files and assigning them to the layer. 

These are the layers I used for my project

mn_streets - over 11000 streets for Manhattan and associated database
mn_hosp - hospital point locations and associated database
mn_fire - firehall point locations and associated database
mn_schools - school locations and associated database
 

ROAD LAYER
road layer cartographic model
In order to create a realistic depiction of traffic flow in Manhattan each road had to be classed into either a major, secondarily major and minor routes.  Using a Manhattan street map, I manually classed my streets using their name into either:

Major = 3
Secondarily Major = 2
Minor = 1

ROAD FRICTION LAYER 

To create this layer I had to get in touch with Stu Sanders, at the West Vancouver Fire Department to estimate the average speed at which a fire truck would travel down a particular street.  He estimated that on major routes which would be equivalent to HWY 1 or a major parkway the fire trucks would reach a speed of about 80km/hr.  On secondarily major routes the equivalent of Hastings Street, truck could reach a speed of 70km/hr.  Minor roads similiar to resedential streets had a max speed of 50km/hr.  I assumed that both fire trucks and ambulances were capable of travelling the same speeds.

TIME ZONES

I broke the day into three traffic flow time zones in which the traffic would travel different speeds.  Using the metrocommute.com webpage I was able to find up to the minute traffic speeds by route in Manhattan.  From these speeds I was able to estimate an average speed which would be travelled by emergency response vehicles depending on the time of day.

ZONE ONE
9pm-6am

ROAD TYPE	SPEED	FRICTION
MAJOR 3	85 km/hr	1
MAJOR 2	70 km/hr	1.21
MINOR 1	50 km/hr	1.7

 

ZONE TWO
9am-3pm
6pm-9pm

ROAD TYPE	SPEED	FRICTION
MAJOR 3	75 km/hr	1.13
MAJOR 2	60 km/hr	1.41
MINOR 1	40 km/hr	2.125

ZONE THREE
6am-9am
3pm-6pm

ROAD TYPE	SPEED	FRICTION
MAJOR 3	60 km/hr	1.41
MAJOR 2	40 km/hr	2.125
MINOR 1	30 km/hr	2.83

SELECTED SCHOOLS LAYER
selected schools layer catographic model

My analysis was best suited for only one or two particular schools.  I arbitrarily selected two schools; one from Upper Manhattan and one from Lower Manhattan after they met the over 1000 student capacity criteria.