טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentYoav Vered
SubjectEvaluating the Effect of Physical Constrains on Spatial
Connectivity
DepartmentDepartment of Civil and Environmental Engineering
Supervisor Professor Filin Sagi
Full Thesis text - in Hebrew Full thesis text - Hebrew Version


Abstract

Geographic physical obstacles are entities that alter potential paths among objects, block or hinder direct crossing, and force means to bypass them. In effect, physical obstacles have a central role in shaping the way that space is perceived. As encounter with obstacles is part of daily routine, and their presence dictates choices taken, their influence must be considered in geospatial data analysis practices. While algorithms considering physical constraints have been proposed in the past, the question of how to measure obstacles influence on spatial datasets has not been treated so far in an integrative manner.  This question poses theoretical concerns that relate to measuring properties that characterize obstacles and their influence, and to ways that such measures can be integrated.


This research proposes categorizing the effect of physical constraints by three measures, including their effect on distance among objects, changes to spatial organization of the data, and their influence on accessibility. Analysis shows that shape and even positional properties of the constraints are insufficient for characterizing their influence. Distance obstruction measures analyze the influence on the connectivity among points, evaluating growth in obstructed distances. Spatial organization measures evaluate changes in data aggregation due to the introduction of obstacles. Accessibility obstruction measures refer to the influence that obstacles have on the choice of routes among objects. Global, as well as local measures are derived to weight influence of the obstacles on space.


Application of the measure on real world examples managed demonstrating how they reflect actual spatial circumstances. The proposed measures can be applied as a pre-processing step to aid decisions regarding improving or decreasing connectivity in a geographic space, and to support optimal location of crossings (e.g., tunnel/bridges) that can take into considerations connectivity improvement and costs of forming such facilitators.