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A top-level “System” class represents any regularly interacting or interdependent group of objects forming a unified whole.  Every system is delineated by its spatial and temporal boundaries, surrounded and influenced by its environment, described by its structure and purpose, and expressed in its processes.

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System Classes: Image


The top-level “Process” represents an action within a system that produces one or more events (state changes) from one or more triggering events.   Each System instance can contain a collection of Process instances.  A Process instance can consume events based on its Rules and produce events from its actions.   If the actions require human assistance, then one or more Task instances are produced from the Process instance.   Devices (machines) involved in process are directed/controlled from attribute settings rather than tasks.

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System Classes: Image


The top-level “Rule” class represents a state that influences the triggering of a process.  Each Process can contain a collection of Rule instances.

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System Classes: Image


The top-level “Role” class represents any capability applicable to a set of parties and/or devices participating in a set of processes.  An instance of this class  (such as “Motor”) is a subclass (or Role class) that contains attributes (such as “Rotation Speed”) relevant to a set of processes. 
A single party may be assigned multiple roles, each within a separate system.  For example, John Smith may be assigned “Employee”, “Customer”, “Passenger”, “Patient”, and “Contact” roles within employment, commerce, travel, health, and social systems, respectively.  A device is assigned a role based on its designed purpose (e.g. sensor, actuator, light, air conditioner) which may span multiple systems.  The purpose of many devices is to assume the same role of Persons.  Thus, a single Role class (e.g. “Dishwasher”) can be assigned to both persons and devices.

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System Classes: Image


The “Reciprocal Role” Relation attribute represents a mirrored role within a system.   For example, a “Registrant” role is a reciprocal of a “Registrar” role in a registry system; an “Employee” role is reciprocal of an “Employer” role in an employment system; and a “Vendor” role is a reciprocal of a “Customer” role within a commerce system.


The top-level “Task” class represents a basic unit of work, assigned to a person assuming a specific role, in context of a set of events (collective state) that trigger a process.

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System Classes: Image
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