Saturday, 30 November 2013
Myths & Common questions about Mapping
As a map-maker, I often get questions related to my field as the world, frustrating as it sounds, do not what is mapping is all about. Likewise, any map-makers do get a lot of questions and that is our unique signature as map-makers, rare species indeed.
I decided to make this video to address some of the common questions/myths related to mapping. Having said that, not much preparation was made for the script. I was talking impromptu at some sections. Even setting up the scene and choosing the clothes took 20-30 minutes. The position, lighting, location of the tie etc...
I would like to thank my dear friend for spending time in setting up the scene, lighting and filming at late night. I credit him for the success of the video. Hence, first time, I am looking for points of improvements for the content and the filming.
Thanks for Watching! Happy Commenting!
Sunday, 24 November 2013
Implementing GIS to tackle local government issue - Part 6 (Final)
Part 5: http://daneshatlas.blogspot.com/2013/11/implementing-gis-to-tackle-local_24.html
Services (Community Planning), 2011, ‘Social and Affordable Housing Strategy’, City of Yarra, viewed on 2nd April 2012,
http://www.yarracity.vic.gov.au/Services/Community-Planning/Social-and-Affordable-Housing-Strategy-/
Services (Community Planning), 2009, ‘Public Health Plan’, City of Yarra, viewed on 2nd April 2012,http://www.yarracity.vic.gov.au/services/Community-Planning/public-health-plan/
Geoprocessing in Information Product production
Geoprocessing for Datasets to be ready
Geoprocessing for generating Information Product
References
City of Yarra, 2012, Your Council, City of Yarra, viewed on 2nd April 2012, http://www.yarracity.vic.gov.au/Your-Council/Services (Community Planning), 2011, ‘Social and Affordable Housing Strategy’, City of Yarra, viewed on 2nd April 2012,
http://www.yarracity.vic.gov.au/Services/Community-Planning/Social-and-Affordable-Housing-Strategy-/
Services (Community Planning), 2009, ‘Public Health Plan’, City of Yarra, viewed on 2nd April 2012,http://www.yarracity.vic.gov.au/services/Community-Planning/public-health-plan/
Implementing GIS to tackle local government issue - Part 5
Part 4: http://daneshatlas.blogspot.com.au/2013/11/implementing-gis-to-tackle-local_8447.html
Part 6 (Final): http://daneshatlas.blogspot.com/2013/11/implementing-gis-to-tackle-local_8847.html
Conceptual Design
Data design
The key data element of address dataset
that would be logically linked with community facility table would be EZI_ADD.
The reason this element is crucial is because EZI_ADD is used to geocode the
facility address. For this linkage to be successful, the addresses of the
community table must be identical of format and address representation.
The minimum map area is 0.01 hectares,
based on CCD .The error tolerance for this project is 10%, to match the error
tolerance of dataset’s positional accuracy. The map scale desired for the
project would be 1: 1000. The map projection that should be employed for the
project area is MGA Zone 55 as this projection minimizes distortions for the
region. Temporal resolution would be every year to cater annual needs of the
city.
Data sources for this information
product come from DSE (public source). The lineage of address dataset starts
from derivation from address information found in Vicmap Property and Vicmap
transport. The addresses were later analysed and categorised and channelled the
results to address dataset. This address dataset has address match rate of 92%
(2008/09). The data standard I will employ in this project would be ANZLIC
Metadata Product Guidelines VER 1.2 July 2011. The reason I chose this standard
is because the metadata format for the DSE datasets are based on this and
applying the same standard would fasten the process of writing product
description. Since the datasets found are readily available in ESRI shapefiles,
there will no need for data format conversion.
Logical Data Model
Most or all the dataset structure for
the project would be vector-based. Below-here is an example the characteristics
of vector transportation dataset.
Fields
|
Data
Type
|
FID
|
Object
ID
|
Shape
|
Geometry
|
PHYS_COND
|
Text
|
ROTATION
|
Float
|
ROAD_REL
|
Text
|
FTYPE_CODE
|
Text
|
CRDATE_PFI
|
Date
|
PFI
|
Long
Integer
|
NAME
|
Text
|
The suitable structure for the data is
object-relational data model. It allows addition of specialized behaviour to
the relational data model which is close to real world behaviour.
The advantages of this model would be it
maintain high data integrity, multiple users are able to update simultaneously
and allows use of legacy and GIS databases. For the project, this model is
chosen because ArcGIS software uses this model and it allows wide range of
relational and objects rules to be applied. Disadvantages would be it is
compromise of two previous models and difficulty of modelling complex
relationships.
For attributes to be linked with the administrative
dataset, the geo-relational data model is most appropriate model for storage
and manipulation of the data. This is because the parcel boundaries are able to
be linked easily with other tables containing data of population
characteristics.
The model (incorporating relational and
objected orientated models) allows relational data model to have
object-orientated extensions. This means various relational and
object-orientated rules are applicable which are needed for the project dataset
(parcel layers and network datasets). Secondly, its ability to allow multiple,
simultaneous updates would maximise GIS analyst working efficiency. For
example, one GIS analyst would be using series of datasets to analyse
accessibility to clinics while another analysts would use the same datasets for
another analysis.
Saturday, 16 November 2013
Implementing GIS to tackle local government issue - Part 4
Part 3: http://daneshatlas.blogspot.com.au/2013/11/implementing-gis-to-tackle-local_16.html
Master Input Data List
The GIS datasets required for the
strategy are address, administrative boundaries, planning zones, property and
transportation network. The non-spatial data required are population, income
and employment status data and table of community service facilities (e.g.
clinics). The address dataset would be utilized to geocode address of community
service facilities and population characteristics data. Administrative
boundaries dataset would be used in defining the council area and linking
population data to census collection districts (CCD).
Planning dataset shows planning
polygons as this would be important in determination of future housing areas.
Property dataset shows the location of parcels and its attributes and would be
used in determination of number of residential lots could be impacted in this
strategy. The tables of population characteristics and facilities would be
utilized to assess the level of accessibility to facilities.
I shall examine address dataset in depth.
The reason I chose this dataset is because it underpins the success of strategy
and hub of connecting of non-spatial data and GIS datasets. Tables containing
facility data and population characteristics are geocoded into the address
dataset. This geocoded facilities/population data would work together with
other datasets in the various geoprocessing methods.
Data identification Items:
1) Dataset
Name: VicMap Address
(a) Identification
No: ANZVI0803002578
(b) Source/Custodian:
Department of Sustainability & Environment (DSE)
(c) Metadata:
Spatial Extent- 34.0S-39.2S,
141E-150.2E. Spatial Reference-
GDA94. Positional accuracy- 90% of
features are within 1mm at plot scale, of true position (5-25m). Attribute accuracy-1%-5% allowable
error. Logical Consistency-1%-5%
allowable error. Currency- 2012(time
of writing)
Data Volume:
(a) Volume:124MB
(b) Format
available: ESRI, MapInfo, DXF,DWG
Data Characteristics
Datasets available are in the ESRI
shapefiles. Below here are the fields of address dataset will be used. Minimum
spatial extent for the project is 144.963 E to 145.045 E and 37.777 S to 37.835
S.
Fields
|
Data Type
|
Name
|
Length
|
Allow Null Values
|
FID
|
Object ID
|
FID
|
-
|
No
|
Shape
|
Geometry
|
Shape
|
-
|
-
|
LGA_CODE
|
String
|
LGA_CODE
|
3
|
Yes
|
GEO_ADD
|
String
|
GEO_ADD
|
45
|
Yes
|
EZI_ADD
|
String
|
EZI_ADD
|
80
|
Yes
|
Source Data Availability
City Council is able to access the
dataset required from DSE and it is fully in digital format (e.g. shapefiles).
Restrictions
No restrictions/royalties placed on the
usage of datasets as this for council use (non-profit).
Part 5: http://daneshatlas.blogspot.com/2013/11/implementing-gis-to-tackle-local_24.html
Part 5: http://daneshatlas.blogspot.com/2013/11/implementing-gis-to-tackle-local_24.html
Implementing GIS to tackle local government issue - Part 3
Part 2: http://daneshatlas.blogspot.com.au/2013/11/implementing-gis-to-tackle-local_13.html
Steps Required Making the Product:
1) All
the datasets are compiled and stored in a geodatabase. The metadata and the
projections used in these datasets are checked to ensure consistency. Functions
needed are data inputs into geodatabases (network, feature datasets)
2) Since
the product (Current Accessibility of City of Yarra) involves various maps,
analysis on datasets are done separately to simplify the operations. For
example, GIS analyst focusing on clinical accessibility would use datasets on
population characteristics, transportation network and clinical locations. The
analysis would involve network analyst and geocoding addresss. The GIS analysts
may consider imposing index values for accessibility.
3) Once
the maps are done, the GIS analyst(s) should ensure the maps produce meet good
quality cartographic standards. These maps initially produced in hardcopy
format are submitted to town planning officers to assess the current accessibility.
4) A
web-enabled GIS is created meantime integrating the spatial data used in the
project. GIS analyst(s) and/or cartographic technicians will design the website
and the necessary characteristics of the online maps. This website is accessed
to city council’s intranet. At the same time, list of existing facilities and
the total targeted population (income disadvantaged) served are produced in
documents (hardcopy formats).
Frequency
of Use:
Function
|
Number
|
Dataset
Input
|
1
|
Geocoding
addresses
|
4
|
Creating
Network dataset
|
2
|
Population
characteristics input
|
4
|
Spatial
Analysis (Closest Facility)
|
2
|
Create
ArcGIS reports
|
1
|
Cartographic
Editing
|
1
|
Printing
|
1
|
Display
in website
|
1
|
Updating
|
4
|
List/other
documents production
|
16
|
Product
|
Annual Production
|
Maps
(Hardcopy)
|
80
|
Lists/Documents
generated
|
80
|
Website
|
1
|
Logical
Linkages:
Logical
Linkages
|
Examples
|
List
to graphic entity
|
Street
address to community service facilities
|
Map
to map
|
Topological
network of the map overlayed on residential maps
Facility
map showing locations to community service facilities
|
Attribute
to attribute
|
Population
characteristics to census collection districts
Type
of clinic to clinic locations
|
Error
Tolerances:
Error
Type
|
Error
|
Tolerance
|
Referential
|
Incorrect
facility attributes
Incorrect
facility names
|
5%
5%
|
Topological
|
Disconnect
in street networks
Disconnect
in public transportation network
|
0%
0%
|
Relative
|
Incorrect
locations of public transport stops (wrong side of street)
|
+ 5m
|
Absolute
|
Incorrect
street address
|
+2.5m
|
Wait
Tolerance: Low (10-60seconds) and Medium (1-5
minutes). These tolerance categories are justified for the products as there
are not urgent in production and they have limited dynamics.
Response
Tolerance: For hardcopy maps, the time required from
start to finish is 8 hours minimum. This has taken into consideration of the
GIS officer has 1 year working experience in GIS and the analysis involved in
producing the map. If the product was requested for the first time, it will be
16-24 GIS hours work due to datasets cleaning and other associated works. For
the website, it will be additional 8 hours minimum, in addition of 2 hours of
integration of GIS data into the online system. The updates to the online GIS
system roughly consume maximum of 3 hours.
Current Costs:
1) GIS
dataset costs
Datasets
|
Cost
|
Address
|
$756
|
Administrative
Boundaries
|
$1584
|
Planning
|
$223
|
Property
|
$893
|
Transport
|
$112
|
Total
|
$3568
|
2) Labour,
other related and Total costs
Hours
|
Annual
Cost for making
|
Total
Costs (AUD)
|
|
Labour
(hardcopy)
|
60
|
$192*(1
product)
|
$15360
|
Labour
(website)
|
22
|
$506
|
$506
|
Miscellaneous
|
$200
|
||
Datasets
|
$3568
|
||
Total
|
~$19700
|
*-Excluding
website cost. Hourly rate is minimum $23 per hour
Benefit Analysis:
1) Financial savings
category: With implementation of GIS in this
strategy, it would eliminate costs required to hire consultants.
2) Direct benefits to
organisation: With GIS, the town planners are
able to make informed decisions of providing facilities. They too would be able
to estimate appropriate costs involved through the output maps.
c 3) External benefits:
The general public will be well served indirectly through GIS implementation.
The future facility and affordable housing will be well placed to serve the
disadvantage population. The state government is able to access these maps or
web-GIS to assess the achievements of city council.
Sign
off: The head of SPU will be signing off the
IPDs and benefit analysis statements. Finally, every sample hardcopy product
must require signature of the head to demonstrate his/her satisfaction of the
product.
Location:
Melbourne VIC, Australia
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