All Topics

A B C D E F G H I J K L M N O P R S T U V W
AM-57 - Data conversion
  • Identify the conceptual and practical difficulties associated with data model and format conversion
  • Convert a data set from the native format of one GIS product to another
  • Discuss the role of metadata in facilitating conversation of data models and data structures between systems
  • Describe a workflow for converting and implementing a data model in a GIS involving an Entity-Relationship (E-R) diagram and the Universal Modeling Language (UML)
DM-02 - Data retrieval strategies
  • Analyze the relative performance of data retrieval strategies
  • Implement algorithms that retrieve geospatial data from a range of data structures
  • Describe the particular advantages of Morton addressing relative to geographic data representation
  • Discuss the advantages and disadvantages of different data structures (e.g., arrays, linked lists, binary trees, hash tables, indexes) for retrieving geospatial data
  • Compare and contrast direct and indirect access search and retrieval methods
KE-18 - Data sharing among public and private agencies, organizations, and individuals
  • Describe formal and informal arrangements that promote geospatial data sharing (e.g., FGDC, ESDI, memoranda of agreements, informal access arrangements, targeted funding support)
  • Describe a situation in which politics interferes with data sharing and exchange
DM-59 - Data warehouses
  • Differentiate between a data warehouse and a database
  • Describe the functions that gazetteers support
  • Differentiate the retrieval mechanisms of data warehouses and databases
  • Discuss the appropriate use of a data warehouse versus a database
DM-62 - Database administration
  • Describe how using standards can affect implementation of a GIS
  • Explain how validation and verification processes can be used to maintain database integrity
  • Summarize how data access processes can be a factor in development of an enterprise GIS implementation
  • Describe effective methods to get stakeholders to create, adopt, or develop and maintain metadata for shared datasets
CV-29 - Design and Aesthetics

Design and aesthetics are fundamental to cartographic practice. Developing students’ skills in design and aesthetics is a critical part of cartography education, yet design is also one of the most difficult part of the cartographic process. The cartographic design process of planning, creating, critiquing, and revising maps provides a method for making maps with intentional design decisions, utilizing an understanding of aesthetics to promote clarity and cohesion to attract the user and facilitate an emotional response. In this entry, cartographic design and the cartographic design process are reviewed, and the concepts of aesthetics, style, and taste are explained in the context of cartographic design.

PD-05 - Design, Development, Testing, and Deployment of GIS Applications

A systems development life cycle (SDLC) denes and guides the activities and milestones in the design, development, testing, and de ployment of software applications & information systems. Various choices of SDLC are available for different types of software applications & information systems and compositions of development teams and stakeholders. While the choice of an SDLC for building geographic information system (GIS) applications is similar to that of other types of software applications, critical decisions in each phase of the GIS development life cycle (GiSDLC) should take into account essential questions concern ing the storage, access, and analysis of (geo)spatial data for the target application. This article aims to introduce various considerations in the GiSDLC, from the perspectives of handling (geo)spatial data. The article rst introduces several (geo)spatial processes and types as well as various modalities of GIS applications. Then the article gives a brief introduction to an SDLC, including explaining the role of (geo)spatial data in the SDLC. Finally, the article uses two existing real-world applications as an example to highlight critical considerations in the GiSDLC.

DM-20 - Discrete entities
  • Discuss the human predilection to conceptualize geographic phenomena in terms of discrete entities
  • Compare and contrast differing epistemological and metaphysical viewpoints on the “reality” of geographic entities
  • Identify the types of features that need to be modeled in a particular GIS application or procedure
  • Identify phenomena that are difficult or impossible to conceptualize in terms of entities
  • Describe the difficulties in modeling entities with ill-defined edges
  • Describe the difficulties inherent in extending the “tabletop” metaphor of objects to the geographic environment
  • Evaluate the effectiveness of GIS data models for representing the identity, existence, and lifespan of entities
  • Justify or refute the conception of fields (e.g., temperature, density) as spatially-intensive attributes of (sometimes amorphous and anonymous) entities
  • Model “gray area” phenomena, such as categorical coverages (a.k.a. discrete fields), in terms of objects
  • Evaluate the influence of scale on the conceptualization of entities
  • Describe the perceptual processes (e.g., edge detection) that aid cognitive objectification
  • Describe particular entities in terms of space, time, and properties
FC-42 - Distance Operations

Distance is a central concept in geography, and consequently, there are various types of operations that leverage the concept of distance. This short article introduces common distance measures, the purpose of distance operations, different types of operations and considerations, as well as sample applications in the physical and social domains. Distance operations can be performed on both vector or raster data, but the operations and results may differ. While performing distance operations, it is important to remember how distance is conceptualized while performing the operation.

FC-14 - Distance, Length, and Direction
  • Describe several different measures of distance between two points (e.g., Euclidean, Manhattan, network distance, spherical)
  • Explain how different measures of distance can be used to calculate the spatial weights matrix
  • Explain why estimating the fractal dimension of a sinuous line has important implications for the measurement of its length
  • Explain how fractal dimension can be used in practical applications of GIS
  • Explain the differences in the calculated distance between the same two places when data used are in different projections
  • Outline the implications of differences in distance calculations on real world applications of GIS, such as routing and determining boundary lengths and service areas
  • Estimate the fractal dimension of a sinuous line
  • Describe operations that can be performed on qualitative representations of direction
  • Explain any differences in the measured direction between two places when the data are presented in a GIS in different projections
  • Compute the mean of directional data
  • Compare and contrast how direction is determined and stated in raster and vector data
  • Define “direction” and its measurement in different angular measures