Introduction:
Viewshed analysis has been around for a long time and has various uses. A few examples of uses are cell tower locations, building site locations, real estate values, and archeology. Two main types of visibility models used are line-of-sight and viewshed. Line-of-sight profiles model point to point visibility, while viewsheds model point-to-area visibility. (Analysis and Visualization of Visibility Surfaces, 2003) Viewshed analysis is used to calculate which locations in a digital elevation model (DEM) can be connected by an uninterrupted straight line to a viewpoint location within any specified distance. (Llobera, 2003)
Using multiple viewsheds and combining them to create a cumulative viewshed is commonly used
A view where the focus of the analysis is on understanding the relationship between points in isolation, and where concern about space in-between is lost and deemed meaningless and inert. (Llobera, 2003) Cumulative viewsheds can be used to identify where the visual presence of features may be greatest. (Llobera, 2003)
My Idea was to determine the visibility of development of hillsides as looking at it from the valley floor and compare Eastside and Westside hills. Using small cumulative viewsheds I can try to determine where the visual presence of houses may be greatest.
The model “viewshed” in Idrisi it creates a 360 degree arc around the point or area of the viewpoint and calculates which cells from the surface image are visible within the specified distance. Creating a continuous viewshed of the area involved would be time prohibitive, not practical for the purpose of this project
Data and sources:
Taxlots, zoning, and vegetation shapefiles are from RLIS data and Oregon10m DEM N fro...
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...of undeveloped areas.
I gained a better understanding of the viewsheds and their complexity and a better knowledge of Irdisi’s processes. Error that happened: reclass sum files ended up the same for trees and without trees which gave me the same results and I needed to go back and redo the analysis.
I gained a better understanding of the viewsheds and their complexity and a better knowledge of Irdisi’s processes.
Bibliography
Analysis and Visualization of Visibility Surfaces. Caldwell, D.R., et al. 2003. 2003.
Joly, Daniel, et al. 2009. A Quantitative Approach to the Visual Evaluation of Landscape. Annals of the Association of American Geographers. 2009, Vol. 99, 2, pp. 292–308.
Llobera, M. 2003. Extending GIS-based visual analysis: the concept of visualscapes. International Journal of Geographical Information Science. 2003, Vol. 17, 1, pp. 25-48.
van Wijk, J.J., "Views on Visualization," Visualization and Computer Graphics, IEEE Transactions on , vol.12, no.4, pp.421,432, July-Aug. 2006. Retrieved from http://ieeexplore.ieee.org.uproxy.library.dc.uoit.ca/stamp/stamp.jsp?tp=&arnumber=1634309&isnumber=34266
Land use in the district of North Vancouver has been a very sensitive issue for many years. In this area, population growth has been substantial, especially because of the area's popular outdoor recreation opportunities. It is this relationship between population pressure and outdoor 'green zones'1 that is at the heart of the conflict in North Vancouver district. Residents are very passionate about, and emotionally attached to, the natural mountainous surroundings. Thus, when development plans were slated for Mountain Forest and Cove Forest, residents did not want development to take place in 'their forests.' The critical question is, how to incorporate influxes of people into a limited amount of urban area while keeping current residents satisfied?
Rose, Gillian. Visual Methodologies: An Introduction to the Interpretation of Visual Materials. Sage Publications (CA), 2001. Print.
West Philadelphia Landscape project has worked with the community for over twenty-five years to restore nature and rebuild the neighborhood through design, strategic planning and educational projects. They have worked in the Mill Creek neighborhood since 1987 and use their experiences to demonstrate how the human population can live healthier, more economic lives. The aim of the project is to make the Philadelphia community more sustainable, with the proposal to manage the area of Mill Creek in a way that would improve the local water quality. The project utilizes landscape literacy as a means to preserve the environment and develop community relations. During the twenty-five years that the project has been running, hundreds of citizens, students and even government officials have taken part in the project in an approach to restore the environment and make the community more sustainable.
Topography is the features of land in an area. Those features can include rivers, mountains, lakes, hills, forrests, etc. A White Heron is overflowing with references to the topography of Maine, and more specifically the coast of Maine. The first sentence of Jewett’s A White Heron gives the reader a preview into the appreciation Jewett has for her home state of Maine, “The woods were already filled with shadows one June evening, just before eight o’clock, though a bright sunset still glimmered faintly among the trunks of the trees” (413). While this description isn’t specific to Maine on the surface, it is specific to Jewett’s interpretation of the woods at sunset in Maine, and the beauty of color writing is that each reader will imagine their own sunset based on their own woods in their own region. Jewett was just beginning and her description of the land around her, and as the story progresses the d...
Rose, G (2001) Visual Methodologies, An introduction to the Interpretation of Visual Materials London: Sage Publications
to use a system or land survey similar to that used in the western part of
A. Line – An irregular soft line is used to establish the eye level/horizon in background between the sky and the field. The diagonal lines define the field and are in an opposite direction of the diagonal lines that define the trunk off the tree in the middle of the picture. The diagonal lines in the field, the horizon line, and the edge of the painting create a linear perspective.
Geographers plan new communities, decide where new highways should be placed, and establish evacuation plans. Computerized mapping and data analysis is known as Geographic Information Systems (GIS), a new frontier in geography. Spatial data is gathered on a variety of subjects and input onto a computer. GIS users can create an infinite number of maps by requesting portions of the data to plot.
Historical geographer JB Harley wrote an essay on Map Deconstruction in 1989, in which Harley argues that a map is more than just a geographical representation of an area, his theory is that we need to look at a map not just as a geographical image but in its entire context. Harley points out that by an examination of the social structures that have influenced map making, that we may gain more knowledge about the world. The maps social construction is made from debate about what it should show. Harley broke away from the traditional argument about maps and examined the biases that govern the map and the map makers, by looking at what the maps included or excluded. Harley’s “basic argument within this essay is that we should encourage an epistemological shift in the way we interpret the nature of cartography.” Therefore Harley’s aim within his essay on ‘Deconstructing the Map’ was to break down the assumed ideas of a map being a purely scientific creation.
The object is imagined to be placed in the third quadrant of the axis system. The plane of projection lies between the observer and the object. The plane of projection is assumed to be transparent. When views are drawn in their relative position, Right side view drawn to the right side of elevation and, Top view comes above the Front view.
3. Blij, H.J. de and Peter O. Muller. Geography: Realms, Regions, and Concepts 2000 Ninth Edition. New York: John Wiley & Sons, Inc., 2000.
The claim being discussed here is that the only way a map or a way of representing things can be useful is if it simplifies the knowledge that the actual territory gives, that is, if it reduces the salient i...
None of the buildings on the street that I live on here in California have very big lawns, which contrasts dramatically with my old neighborhood because back in Connecticut most houses have almost an acre of land per house. There are multiple trees on my moms property and the backyard is basically up against a forest. Now there 's still a good amount of trees on the street I currently live on in here California, but much less and most of them are much smaller or are palm trees. The houses and apartment complexes
De, Blij Harm J., and Peter O. Muller. Geography: Realms, Regions, and Concepts. New York: J. Wiley, 1997. 340. Print.