Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Alex B. Owusu Geographic Data Visualization Geovisualization Showing or representing geographic data Quantitative Qualitative How do you represent geographic data to communicate exactly what you want to Making the representation for people to see without explanation Intuitive Line Point Polygon Colours Area Surface Description Objectives The main components, or building blocks, of a map The qualities of a map that are important in communicating information to map users The types of maps that can be developed to visually and quickly communicate information to an audience 7 Mapmakers need to understand… • The objective(s) of the map (the message) • The people who may use the map (the audience) • The data that will be displayed in the map (the info • rmation available) • The use of graphics software for displaying map information • The final format of the printed or digital version of the map (the product) 8 Bibliography M.J. Kraak and F. Ormeling (2009): Cartography: Visualization of Spatial Data. Prentice Hall T. Slocum (2003): Thematic Cartography and Geographic Visualization. Prentice Hall. Teaching and learning methods Lectures, lab work, self-study on articles in magazines Required infrastructure Class room with computer projector, computer laboratory with GIS software and data Assessment To pass this module, the students are required to complete all exercises; successfully present the final project and pass the written exam 9 •Symbology •Direction •Scale •Legend •Locational inset •Neatline •Typography •Color and contrast •Ancillary information (caveats and disclaimers) 10 • The art of expression • Using graphics and text to convey meaning • Most GIS packages offer a robust suite of symbology choices 11 The representation of map figures to their on the ground equivalents A key part of most maps Several different approaches Graphical Equivalent Proportional http://www.proza.ru/pics/2011/08/10/103.jpg 12 • People associate colors of mapped features with events, emotions, and socio-economic status • Although men and women react similarly to color, some reactions may vary depending on culture (Valdez & Mehrabin 1994) • How do you react to different colors? CMYK http://image-24.ru/wp-content/uploads/2010/06/rgb.gif Red, Green, Blue - Additive colors http://t1.ftcdn.net/jpg/00/12/11/50/400_F_12115010_WVSCD8xd8l samF2GU7p6QXxvKrdpn11A.jpg Cyan, Magenta, Yellow -Subtractive colors http://docs.huihoo.com/mapserver/5.2.1/_images/carto-elements.png http://www.lib.utexas.edu/maps/americas/middleamerica.jpg Audience- are they all familiar with your study area? Is an inset required? Will others need to track your sources ? Do you need to record where the map is stored? Are revisions expected or will the study area change (date)? Title, scale, author, and north arrow are safe bets Publication outlets may have their own guidelines Wrong audience Omitting a necessary element Too much clutter (symbology) Too much detail (annotation) Plotter or printer produces something different than what you see on the screen How to Lie with Maps (Monmonier 1996) Drawing the Line, Tales of Maps and Controversy (Monmonier 1995) Models of reality Many simply accept maps at face value Be discriminate in your appraisal and interpretation of maps Be clear and ethical in your creation of maps PROBABILISTIC MAP OF SEISMIC RISK Map from Atlas of natural and technological hazards and risks of emergencies in the Republic of Kazakhstan (2010) Reference Topographic Dot Picture Symbol Graduated Symbol Multivariate symbol Network Flow Isopleth Reference http://www.luxembourg.co.uk/pics/railnetw.jpg Choropleth Dasymetric Area qualitative Stepped surface Hypsometric Reference HTML embeds PNG, JPEG and GIF Animation possible with GIF Drawing extensions with SVG (XML) Otherwise, need JAVA or FLASH GIS data can be web enabled with on-line products such as Arc Server/IMS and GeoMedia Web Map, MapInfo Envinsa Map open source tools [Isopleth, Stepped Surface, Hypsometric] Gridded fishnet Realistic perspective Hill-shaded Image map Multiple views Animation Moving map Fly thru Fly by Unload interaction functions to web client Build and make visible 3D models VRML established as 3D web equivalent of HTML GeoVRML is geographically enabled VRML GML, X3D now available Public domain Web tools (CosmoCreate and Player) Works for both immersive and passive displays Symbolization at feature level, any dimension object Integrated environment to develop, test and distribute cartographic methods Combine traditional cartographic portrayal techniques, animation, and 3-dimensional display Importance of nodes and georeferencing Worlds (GeoVRML 1.0) Incorporates visual field depth via proximity sensor and zoom Focus on your audience Understand your data Define your representation Highlight your key points Use marsh up where you can Give spatial reference Do not obscured other information Don’t create information overload http://colorbrewer2.org/ Earth.google.com Create animation for presentations – Using AVI – Time animation or layer animation Use 3D where necessary 3 SECTIONS A 20 SHORT ANSWERS MR GERALD YIRA 2 QUESTIONS ANSWER 1 SECTION C: 2 QUESTIONS ANSWER 1 Maps are projected and not drawn in order to minimize distortions. Discuss five properties of map that are likely to be distorted when maps are drawn? Explain any three of the following: Vector Data Raster Data Dissolve Buffer Merge You are contracted to create a digital map from a hard copy map. Explain exactly how you will execute the exercise to its logical conclusion. a. Explain the term Geoprocessing b. Use a flowchart to model how you will perform spatial analysis to determine watershed areas that are likely to suffer from pesticides contamination. Explain any five Errors that are likely to occur during GIS data creation. How do you avoid them?