Blog Archives

MFworks Tutorial – 03 Incremental Linkage

This operation infers the lineal characteristic of raster cells, by equating consecutive locations with a set of straight lines between them (Figure 1-3). Based on its relations with neighboring cells that have the same attribute value, each cell is given a linkage value indicating how it is linked to other cells.

Incremental Linkage, cell value infers the linear structure it represents.
© Thinkspace

By assigning a value to each cell equivalent to the linear feature it represents it is possible to create a network similar to a road network. The smaller the cell resolution, the better the real-world road network will be approximated by this procedure.

Read more

Posted in mfworks
Tags: , , ,

MFworks Tutorial – 04 Directional Identifier

The second step to creating a road network in raster GIS is to impose constraints on the flow that can take place from cell to cell. The value assigned to the centre cell in a 3×3 window indicates the directions the flow can take in and or out of this cell. Figure 1-5 shows how a cell value of 10 is inferred from flow in direction 8 and 2.


Tomlin’s directional identifiers: Cell values indicate possible flow direction in or out of cell

The directional identifiers that are to be assigned to any given cell in a road network can be directly inferred from the Incremental Linkage values,

Read more

Posted in mfworks
Tags: , , ,

MFworks Tutorial – 05 Cost surface

Usually, to generate a cost-of passage surface, several variables will be collapsed into one layer. These variables might be road class, average speed, traffic density, and congestion during specific time of day or other factors that contribute to the overall cost variable. The cost-of-passage surface can be defined by a variety of measurement units: time, fuel consumption, money or other possible cost units, for which the least cost passage is to be determined.

Using average speed and time as a means of inferring cost-of-passage is among the most common approach in network analysis, since it is easy to use and calculate. However, “least cost” does not always need to be “least time”; it may just as well be least fuel,

Read more

Posted in mfworks
Tags: , , , ,

ARTICLES and PAPERS
What is risk?
What is risk, and how can it be expressed? Should risk be defined through probabilities or should ri[...]
The Final Frontier: The Northern Sea Route
Sought after by polar explorers and long awaited by the shipping community: The Northern Sea Route. [...]
BOOKS and BOOK CHAPTERS
Book review: Supply Chain Risk Management
Edited by Robert B. Handfield, the book Supply Chain Risk Management: Minimizing Disruptions in Glob[...]
Supply Chain Nirvana
Is there something like a Supply Chain Nirvana, where it all comes together and where a firm's suppl[...]
REPORTS and WHITEPAPERS
Global Risks 2008 - A prediction come true
In my post on Hyper-optimization and supply chain vulnerability: an invisible global risk? I highlig[...]
Supply Chain and Transport Risk
In our interconnected world, safety, reliability and efficiency can only be secured through collabor[...]
from HERE and THERE
Why risk is the buzzword in supply chain management
A new field has emerged with the field of supply chain mangement. It's called supply chain risk. Wha[...]
Lean logistics = risky logistics?
A posting on Evolving Excellence called Long is not Lean caught my attention the other day. The auth[...]