2021 QUARTER 02

A B C D E F G H I J K L M N O P R S T U V W
AM-94 - Machine Learning Approaches

Machine learning approaches are increasingly used across numerous applications in order to learn from data and generate new knowledge discoveries, advance scientific studies and support automated decision making. In this knowledge entry, the fundamentals of Machine Learning (ML) are introduced, focusing on how feature spaces, models and algorithms are being developed and applied in geospatial studies. An example of a ML workflow for supervised/unsupervised learning is also introduced. The main challenges in ML approaches and our vision for future work are discussed at the end.

KE-19 - Managing GIS&T Operations and Infrastructure

This article discusses the key role of effective management practices to derive expected benefits from the infrastructure and operations of enterprise GIS, including needs assessment, data evaluation and management, and stakeholder involvement. It outlines management factors related to an emerging application of enterprise GIS.  How to configure GIS infrastructure and operations to support enterprise business needs is the focus. When appropriate, additional information is provided for programs, projects, and activities specifically relevant for equity and social justice.

AM-06 - Map algebra
  • Explain the categories of map algebra operations (i.e., local, focal, zonal, and global functions)
  • Explain why georegistration is a precondition to map algebra
  • Differentiate between map algebra and matrix algebra using real examples
  • Perform a map algebra calculation using command line, form-based, and flow charting user interfaces
  • Describe a real modeling situation in which map algebra would be used (e.g., site selection, climate classification, least-cost path)
  • Describe how map algebra performs mathematical functions on raster grids
CV-23 - Map analysis
  • Create a profile of a cross section through a terrain using a topographic map and a digital elevation model (DEM)
  • Measure point-feature movement and point-feature diffusion on maps
  • Describe maps that can be used to find direction, distance, or position, plan routes, calculate area or volume, or describe shape
  • Explain how maps can be used in determining an optimal route or facility selection
  • Explain how maps can be used in terrain analysis (e.g., elevation determination, surface profiles, slope, viewsheds, and gradient)
  • Explain how the types of distortion indicated by projection metadata on a map will affect map measurements
  • Explain the differences between true north, magnetic north, and grid north directional references
  • Compare and contrast the manual measurement of the areas of polygons on a map printed from a GIS with those calculated by the computer and discuss the implications these variations in measurement might have on map use
  • Determine feature counts of point, line, and area features on maps
  • Analyze spatial patterns of selected point, line, and area feature arrangements on maps
  • Calculate slope using a topographic map and a DEM
  • Calculate the planimetric and actual road distances between two locations on a topographic map
  • Plan an orienteering tour of a specific length that traverses slopes of an appropriate steepness and crosses streams in places that can be forded based on a topographic map
  • Describe the differences between azimuths, bearings, and other systems for indicating directions
CV-34 - Map Icon Design

The use of map icons is an efficient way to condense a map object into a concise expression of geospatial data. Like all cartographic design, map icon design merges artistic and scientific elements into symbolic representations intended to be readily legible to map readers. This entry reviews the types of map icons and elements of icon design, including the ways in which the visual variables are used in map icon communication. As communicative devices, icons are imbued with cultural meanings and can oftentimes lead to the preservation of stereotypes. This review concludes with an examination of icons’ perpetuation of – and challenge to – cultural stereotypes.

CV-22 - Map interpretation
  • Identify the landforms represented by specific patterns in contours on a topographic map
  • Hypothesize about geographic processes by synthesizing the patterns found on one or more thematic maps or data visualizations
  • Match features on a map to corresponding features in the world
  • Compare and contrast the interpretation of landscape, geomorphic features, and human settlement types shown on a series of topographic maps from several different countries
CV-30 - Map Production and Management

Map production describes the experience of managing the many aspects and details of map creation. Often the map product is created for someone else—a client, supervisor, or instructor. Describing the intention of the map and evaluating available resources ahead of the project can help the cartographer define content requirements, stay on task, and ultimately meet deadlines. The project management life cycle involves clear communication between the cartographer and client, with resolutions to common questions best addressed at the beginning of the project. The process then iteratively cycles through phases that include research and production, followed by quality control, and concludes with file preparation and delivery.

CV-06 - Map Projections

Map projection is the process of transforming angular (spherical / elliptical) coordinates into planar coordinates. All map projections introduce distortion (e.g., to areas, angles, distances) in the resulting planar coordinates. Understanding what, where, and how much distortion is introduced is an important consideration for spatial computations and visual interpretation of spatial patterns, as well as for general aesthetics of any map.

CV-21 - Map Reading

Map reading is the process of looking at the map to determine what is depicted and how the cartographer depicted it. This involves identifying the features or phenomena portrayed, the symbols and labels used, and information about the map that may not be displayed on the map. Reading maps accurately and effectively requires at least a basic understanding of how the mapmaker has made important cartographic decisions relating to map scale, map projections, coordinate systems, and cartographic compilation (selection, classification, generalization, and symbolization). Proficient map readers also appreciate artifacts of the cartographic compilation process that improve readability but may also affect map accuracy and uncertainty. Masters of map reading use maps to gain better understanding of their environment, develop better mental maps, and ultimately make better decisions. Through successful map reading, a person’s cartographic and mental maps will merge to tune the reader’s spatial thinking to the reality of the environment.

GS-26 - Mapping Spatial Justice for Marginal Societies

Marginal populations are those populations that are often overlooked by government, dependent upon non-governmental aid, and lack access to basic resources such as water, food, shelter, and security.  However, these groups are increasingly included in partnerships to map their resources (or lack thereof), develop basic applications in geospatial data collection, and devise innovative approaches to participatory mapping using geospatial technologies to address local and regional problems. Rapid technological changes and increased access to mobile geospatial tools enhance data creation efforts to map marginal populations and identify their needs. However, such mapping activities reveal fundamental inequities in collecting, disseminating, and visualizing spatial data.  This chapter defines marginal populations and provides an overview of data needs, geospatial tools, and ethical obligations necessary for these partnerships.

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