In recent years, network analysis techniques have been applied to urban masterplanning - notably by the Space Syntax consultancy in London - and there are now many tried and tested techniques which can be used to quantify the characteristics of each link or space in an urban network.
These measures have been shown to correlate to human health, land values, town centre vitality, pedestrian flows, land use, traffic volumes, accidents and crime, and can provide valuable insights into the performance of a masterplan proposal.
CityCAD models are constructed from streets and nodes and are well suited to this type of analysis. A combination of technologies, including CityCAD, the open source Quantum GIS application and the new sDNA toolkit, can be used to process and analyze your street networks.
What is sDNA?
sDNA is a network analysis toolkit developed at Cardiff University in the UK. It includes a wide range of network analysis options, and is available for free as a plugin for AutoCAD, AutoCAD Map 3D and ArcGIS. It can also be used in a standalone form to analyse networks in shapefile (SHP) format.
- For more details about sDNA please visit http://www.cardiff.ac.uk/sdna
Please note that sDNA was not developed by Holistic City Limited.
We can work with you and specialist partners to provide customized network analysis for your project. We can offer a range of services depending on your requirements, for example:
- We can integrate customized network analysis with your CityCAD installation
- Analysis results can be packaged and included in automatically generated reports
- Network analysis can be integrated with your own data and models
- Results can be output and formatted to the exact requirements of your project
What can be measured?
sDNA can compute the following measures:
- Accessibility within a radius
- Closeness (compatible with existing literature)
- Improved accessibility measures
- Flows / betweenness for a radius
- Network density within a radius
- Link count
- Junction count
- Total connectivity
- Total length
- Total angular cost
- Total weight
- Total geodesic length
- Total crow flight distance
- Mean geodesic diversion ratio
- Efficiency of overall shape of urban masterplan
- Convex hull area
- Convex hull perimeter
- Convex hull maximum radius
- Bearing of maximum radius
- Two phase (generation / assignment) model
- Two phase betweenness
sDNA aims to promote the use of spatial network analysis as widely as possible in urban design, planning, architecture, scientific research and beyond. To this end, they offer training in the use of the sDNA software.
Their syllabus covers:
- How to use sDNA to optimise urban infrastructure and land use to achieve economic, health, energy and other planning objectives
- Network urban performance modelling
- Theoretical basis of spatial network analysis
- Use of sDNA software in design
- Use of sDNA software in analysis and research
- Interpretation of results
- Relevant evidence to use as a basis for design and policy decisions
Please visit the sDNA website for more information about their training options.