{{Infobox software , name = STEM , logo = STEM LOGO.jpg , logo size = 200px , screenshot = , caption = , developer = IBM, BfR,

Eclipse Foundation The Eclipse Foundation AISBL is an independent, Europe-based not-for-profit corporation that acts as a steward of the Eclipse open source software development community, with legal jurisdiction in the European Union. It is an organization suppo ...

, released = 2006 , latest release version = {{wikidata, property, reference, P348 , latest release date = , programming language = Java software , operating system = Any ( Java software) , language = English (with Java National Language Support) , genre =

Scientific software Software is a set of computer programs and associated documentation and data. This is in contrast to hardware, from which the system is built and which actually performs the work. At the lowest programming level, executable code consists ...

, license = EPL , website = {{url, http://www.eclipse.org/stem/ The Spatiotemporal Epidemiological Modeler (STEM) is

free software Free software or libre software is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any adapted versions. Free software is a matter of liberty, no ...

available through the

. Originally developed by

IBM Research IBM Research is the research and development division for IBM, an American multinational information technology company headquartered in Armonk, New York, with operations in over 170 countries. IBM Research is the largest industrial research or ...

, STEM is a framework and development tool designed to help scientists create and use spatial and temporal models of infectious disease. STEM uses a component software architecture based on the

OSGi OSGi is an open specification and open source project under the Eclipse Foundation. It is a continuation of the work done by the OSGi Alliance (formerly known as the Open Services Gateway initiative), which was an open standards organization fo ...

standard. The Eclipse

Equinox A solar equinox is a moment in time when the Sun crosses the Earth's equator, which is to say, appears directly above the equator, rather than north or south of the equator. On the day of the equinox, the Sun appears to rise "due east" and se ...

platform is a reference implementation of that standard. By using a component software architecture, all of the components or elements required for a disease model, including the code and the data are available as software building blocks that can be independently exchanged, extended, reused, or replaced. These building blocks or plug-ins are called eclipse "plug-ins" or "extensions". STEM plug-ins contain

denominator data In epidemiology, data or facts about a population is called denominator data. Denominator data are independent of any specific disease or condition. This name is given because in mathematical models of disease, disease-specific data such as the ...

for administrative regions of interest. The regions are indexed by standard ( ISO3166) codes. STEM currently includes a large number of plug-ins for the 244 countries and dependent areas defined by the Geographic Coding Standard maintained by the

International Organization for Standardization The International Organization for Standardization (ISO ) is an international standard development organization composed of representatives from the national standards organizations of member countries. Membership requirements are given in Ar ...

. These plug-ins contain global data including

geographic data Geographic data and information is defined in the ISO/TC 211 series of standards as data and information having an implicit or explicit association with a location relative to Earth (a geographic location or geographic position). It is also call ...

, population data,

demographics Demography () is the statistical study of populations, especially human beings. Demographic analysis examines and measures the dimensions and dynamics of populations; it can cover whole societies or groups defined by criteria such as ed ...

, and basic models of

disease A disease is a particular abnormal condition that negatively affects the structure or function of all or part of an organism, and that is not immediately due to any external injury. Diseases are often known to be medical conditions that a ...

. The disease models distributed with STEM include epidemiological compartment models. Other plug-ins describe relationships between regions including nearest-neighbor or adjacency relationships as well as information about

transport Transport (in British English), or transportation (in American English), is the intentional movement of humans, animals, and goods from one location to another. Modes of transport include air, land ( rail and road), water, cable, pipelin ...

ation, such as connections by

road A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation. There are many types of ...

s and a model of

air transportation Aviation includes the activities surrounding mechanical flight and the aircraft industry. ''Aircraft'' includes fixed-wing and rotary-wing types, morphable wings, wing-less lifting bodies, as well as lighter-than-air craft such as hot ai ...

. Relationships between regions can then be included in models of how a disease spreads from place to place. To accomplish this, STEM represents the world as a "graph". The

nodes In general, a node is a localized swelling (a "knot") or a point of intersection (a Vertex (graph theory), vertex). Node may refer to: In mathematics *Vertex (graph theory), a vertex in a mathematical graph *Vertex (geometry), a point where two ...

in the graph correspond to places or regions, and the edges in the graph describe relationships or connections between regions. Both the nodes and the edges can be labeled or "decorated" with a variety of denominator data and models. This graphical representation is implemented using the

Eclipse Modeling Framework Eclipse Modeling Framework (EMF) is an Eclipse-based modeling framework and code generation facility for building tools and other applications based on a structured data model. From a model specification described in XML Metadata Interchange ...

(EMF). Since a model can be built up using separate subgraphs, STEM enables model

composition Composition or Compositions may refer to: Arts and literature *Composition (dance), practice and teaching of choreography *Composition (language), in literature and rhetoric, producing a work in spoken tradition and written discourse, to include v ...

. Predefined subgraphs defining different countries can be assembled with a drag and drop interface. New disease vectors can simply be added to existing models by augmenting the model with a new set of edges. The architecture also supports collaboration as users can not only create new models and compose new scenarios but also exchange these models and scenarios as reusable components and thereby build on each other's work. As an open source project, users are encouraged to create their own plug-ins (both data and models) and, if appropriate, to contribute their work back to the project.

External links

* /www.eclipse.org/stem/ STEM Free science software Free health care software Epidemiology Public health and biosurveillance software IBM software Space and time