Glossary of Terms - M

A two-dimensional visual portrayal of geospatial data. A map is not the data itself.
map projection
A coordinate conversion from a geodetic coordinate system to a planar surface, converting geodetic latitude and longitude to plane (map) coordinates. The result is a two-dimensional coordinate system called a projected coordinate reference system.
map scale
The relationship between distance on a map and the corresponding distance on the earth`s surface. Map scale is often recorded as a representative fraction such as 1:1,000,000 (1 unit on the map represents a million units on the earth`s surface) or 1:24,000 (1 unit on the map represents 24,000 units on the earth`s surface). The terms `large` and `small` refer to the relative magnitude of the representative fraction. Since 1/1,000,000 is a smaller fraction than 1/24,000, the former is said to be a smaller scale. Small scales are often used to map large areas because each map unit covers a larger earth distance. Large-scale maps are employed for detailed maps of smaller areas.
An observation event whose value property is a value of some natural phenomenon. A measurement usually refers to the measuring device and procedure used to determine the value, such as a sensor or observer, analytical procedure, simulation or other numerical process. A measurement feature binds the result to the (spatiotemporal) location where the measurement was made.
message broker
Hubs designed to route and manage message traffic between various applications. May include transformation for incompatible messages.
Source: ISO 19115; KOGIS Switzerland; Co-ordination for GIS in the federal administration of Switzerland
"Data about data or a service. Metadata is the documentation of data. In human-readable form, it has primarily been used as information to enable the manager or user to understand, compare and interchange the content of the described data set. In the Web Services context, XML-encoded (machine-readable and human-readable) metadata stored in catalogs and registries enables services to use those catalogs and registries to find data and services.
metadata dataset
Source: ISO 19101
Metadata describing a specific dataset
metadata entity
Source: ISO 19115
Group of metadata elements and other metadata entities describing the same aspect of data. Note 1: A metadata entity may contain one or more metadata entities. Note 2: A metadata entity is equivalent to a class in UML terminology
metadata schema
Source: ISO 19101
Coceptual schema describing metadata Note: ISO 19115 describes a standard for metadata schema.
metadata section
Source: ISO 19115
Subset of metadata that defines a collection of related metadata entities and elements.
metadata translator
Software based on the OpenGIS Specification that will be configured by two diverse Information Communities to enable automated data integration or sharing to the degree that their metadata schema overlap.
Mid-Term Technical Baseline Target
The Mid-Term Technical Baseline Target is the subset of the elements of the Technical Plan that are scheduled to be completed between one and two calendar years into the future.
Software in a distributed computing environment that mediates between clients and servers.
OGC`s Multi-Hazard Mapping Initiative (MMI) Phase I (2001) was a pilot project sponsored by the US Federal Emergency Management Agency (FEMA) that established a limited operational framework of interoperable services to illustrate the advantages of using products with OGC interfaces to access, fuse and visualize critical spatial information in support of FEMA multi-hazard mitigation, response and recovery functions.
modeling languages
Well-known "languages" to encode the semantics, syntax and schema of geospatial and geoprocessing-related information resources. They apply to all Application Domain Models and Runtime (Model) Components.
OGC`s Military Pilot Project (MPP) (2001) was a collaborative effort that tested the interoperability of commercial geoprocessing products in the defense and intelligence (DI) domain.

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