Snippets (text quotes and extracts from authoritative sources)

A Snippet is a short quote or extract (typically a phrase, a sentence, or at most a few sentences) from an authoritative source document such as a specification, technical manual, or design manual. Throughout this site, content is often related to supporting Snippets and each Snippet page links back to the content pages that reference it! The Snippet and Note concepts are very closely related and they support each other.

The Snippet concept is also at the heart of the Parsing Analysis recipe for UML® and SysML®

Kind Snippet quote/extract Source UML keywords SysML keywords Keywords
INFO When exiting from a composite State, exit commences with the innermost State in the active state configuration. This means that exit Behaviors are executed in sequence starting with the innermost active State. Unified Modeling Language 2.5.1 State, StateMachine, Behavior, State::exit, composite State, State::/isComposite, substate, active state configuration
INFO When exiting from an orthogonal State, each of its Regions is exited. After that, the exit Behavior of the State is executed. Unified Modeling Language 2.5.1 State, StateMachine, Behavior, State::exit, State::/isOrthogonal, orthogonal Region, Region
INFO When he sets Sophie down, she begins to plead for her life, believing that the giant will eat her. Wikipedia Webel Parsing Analysis
EXAMPLE, INFO When Monitor Traction is enabled, it begins listening for signals coming in from the wheel and accelerometer, as indicated by the signal receipt symbols on the left, which begin listening automatically when the activity is enabled. OMG Systems Modeling Language (SysML) 1.6 Signal, accept signal action, SignalEvent, AcceptEventAction, AcceptEventAction::isUnmarshall SysML specification figure
INFO When multiple triggers are defined for a Transition, they are logically disjunctive, that is, if any of them are enabled, the Transition will be triggered. Unified Modeling Language 2.5.1 State, StateMachine, Transition, Trigger, Transition::trigger, Event, Event occurrence, Trigger::event
NOTATION When several item flows having the same direction are represented, only one triangle is shown, and the list of item flows, separated by a comma is presented. OMG Systems Modeling Language (SysML) 1.6 Connector, Association ItemFlow
INFO When the Action is enabled by other means, values are computed as specified for the ValuePins and ActionInputPins owned by an Action, and the results are provided as inputs to the Action when it begins execution. Unified Modeling Language 2.5.1 Activity, Activity Diagram, Action, Pin, InputPin, ValuePin, ActionInputPin, execution
INFO When the Activity is invoked, values may be passed into the Activity execution on input Parameters (i.e., those with direction in or inout) and values may be passed out .. on output Parameters (i.e., those with direction inout, out or return). Unified Modeling Language 2.5.1 Activity, Behavior, Parameter, ActivityParameterNode, ParameterDirectionKind::in, ParameterDirectionKind::out, ParameterDirectionKind::inout, ParameterDirectionKind::return, Parameter::direction, execution
INFO When the brake pressure goes to zero, disable control values are emitted from the control operator. The first one disables the monitor, and the rest have no effect. OMG Systems Modeling Language (SysML) 1.6 SysML specification figure, ControlOperator, ControlValueKind, ControlValueKind::disable, ControlValueKind::enable
INFO When the computer is in StandBy, y.sigsp [ERROR] is set to 8, and when the computer is On, y.sigsp [ERROR] is set to 3. SysPhS-1.1 StateMachine, State, Transition, ChangeEvent, ChangeEvent::changeExpression SysPhS, SysML, Systems Modeling Language
INFO When the LoopNode begins executing, the tokens on the loopVariableInput InputPins are moved to the corresponding loopVariable OutputPins before the first iteration of the loop. Unified Modeling Language 2.5.1 Activity, Activity Diagram, LoopNode, LoopNode::loopVariable, ActivityNode::outgoing, ActivityEdge, OutputPin, LoopNode::loopVariableInput, InputPin
When the «controlOperator» stereotype is applied to behaviors, the behavior takes control values as inputs or provides them as outputs, that is, it treats control as data OMG Systems Modeling Language (SysML) 1.6 Behavior, Operation ControlOperator
When the «controlOperator» stereotype is not applied, the behavior may not have a parameter typed by ControlValue. OMG Systems Modeling Language (SysML) 1.6 Behavior, Operation ControlOperator, ControlValueKind
INFO When the «nobuffer» stereotype is applied to object nodes, tokens arriving at the node are discarded if they are refused by outgoing edges, or refused by actions for object nodes that are input pins. OMG Systems Modeling Language (SysML) 1.6 ObjectNode, ActivityNode::outgoing, InputPin, Action::/input «noBuffer», NoBuffer
INFO When the «optional» stereotype is applied to parameters, the lower multiplicity shall be equal to zero. This means the parameter is not required to have a value for the activity or any behavior to begin or end execution ... OMG Systems Modeling Language (SysML) 1.6 Parameter, MultiplicityElement::/lower, multiplicity «optional», Optional, Optional, required
INFO When the «overwrite» stereotype is applied to object nodes, a token arriving at a full object node removes one that is already there before being added (a full object node has as many tokens as allowed by its upper bound). OMG Systems Modeling Language (SysML) 1.6 ObjectNode, MultiplicityElement::/upper Overwrite, «overwrite»
CONSTRAINT, INFO When the «probability» stereotype is applied to edges coming out of decision nodes and object nodes, it provides an expression for the probability that the edge will be traversed. These shall be between zero and one inclusive, and add up to one ... OMG Systems Modeling Language (SysML) 1.6 DecisionNode, ObjectNode, ActivityEdge «probability», Probability, Probability::probability
CONSTRAINT, INFO When the «probability» stereotype is applied to output parameter sets, it gives the probability the parameter set will be given values at runtime. These shall be between zero and one inclusive, and add up to one for output parameter sets of the same ... OMG Systems Modeling Language (SysML) 1.6 Parameter::parameterSet, ParameterSet «probability», Probability, Probability::probability
INFO When the «rate» stereotype is applied to an activity edge, it specifies the expected value of the number of objects and values that traverse the edge per time interval, that is, the expected value rate at which they leave the source node and arrive at ... OMG Systems Modeling Language (SysML) 1.6 ActivityEdge, DirectedRelationship::/source, DirectedRelationship::/target, object token, value, ActivityNode Rate, «rate»
NOTATION Where a subject is a Classifier with a standard stereotype, the keyword for the stereotype shall be shown in guillemets above the name of the subject. Unified Modeling Language 2.5.1 UseCase, UseCase Diagram, UseCase::subject, Classifier, «keyword», Stereotype, guillemets
INFO Whereas flow properties specify what “can” flow in or out of a block, item flows specify what “does” flow between blocks and/or parts in a particular usage context. OMG Systems Modeling Language (SysML) 1.6 ItemFlow
INFO While the electron has a negative electric charge, the positron has a positive electric charge, and is produced naturally in certain types of radioactive decay. The opposite is also true: the antiparticle of the positron is the electron. Wikipedia
INFO While the ExecutableNode is executing, it is considered to hold a single control [token] indicating it is execution [executing]. Unified Modeling Language 2.5.1 Behavior, Activity, Activity Diagram, ExecutableNode, implicit join, ControlFlow, ActivityNode::incoming, token, control token
INFO While the monitor is enabled, it outputs a modulation frequency for applying the brakes as determined by the ABS system. OMG Systems Modeling Language (SysML) 1.6 SysML specification figure, ControlOperator, ControlValueKind, ControlValueKind::disable, ControlValueKind::enable
INFO Within an Activity, inputs to and outputs from an Activity are handled using ActivityParameterNodes. Unified Modeling Language 2.5.1 Activity, Behavior, Parameter, ActivityParameterNode
INFO Within the limits of experimental accuracy, the electron charge is identical to the charge of a proton, but with the opposite sign. Wikipedia
INFO You may have seen a similar table before with slightly different choices. For example, you will sometimes see velocity (in ) chosen as the across variable for translational motion. The choices above are guided by two constraints. Modelica By Example Modelica, acausal connection
CONSTRAINT zero_input_parameters If the DecisionNode has no decisionInputFlow and an incoming ControlFlow, then any decisionInput Behavior has no in parameters. Unified Modeling Language 2.5.1 DecisionNode, DecisionNode::decisionInputFlow, ControlFlow, DecisionNode::decisionInput, Behavior, Parameter, ParameterDirectionKind::in, ActivityNode::incoming, Behavior::ownedParameter, Behavior::inputParameters()
INFO [SysML1.6: PREFER SysML1.7] A DirectedFeature indicates whether the feature is supported by the owning block (provided), or is to be supported by other blocks for the owning block to use (required), or both ... OMG Systems Modeling Language (SysML) 1.6 DirectedFeature, FeatureDirectionKind::provided, FeatureDirectionKind::required, FeatureDirectionKind::providedrequired, FeatureDirectionKind
INFO ~InterfaceBlock::original : InterfaceBlock [1] The InterfaceBlock that this is a conjugation of. OMG Systems Modeling Language (SysML) 1.6 InterfaceBlock, ~InterfaceBlock::original, ~InterfaceBlock
CONSTRAINT «designConstraint»: satisfied by a block or part. OMG Systems Modeling Language (SysML) 1.6 ExtendedRequirement, AbstractRequirement, «performanceRequirement», Block, part property, MD:PartProperty requirements engineering
INFO «effbd» Specifies that the activity conforms to the constraints necessary for EFFBD. OMG Systems Modeling Language (SysML) 1.6 Activity «effbd» non-normative
CONSTRAINT «functionalRequirement»: satisfied by an operation or behavior OMG Systems Modeling Language (SysML) 1.6 Operation, Behavior «functionalRequirement», ExtendedRequirement, AbstractRequirement requirements engineering
CONSTRAINT «interfaceRequirement»: satisfied by a port, conector, item flow, and/or constraint property. OMG Systems Modeling Language (SysML) 1.6 Operation, Connector ExtendedRequirement, AbstractRequirement, «interfaceRequirement», ItemFlow, constraint property requirements engineering
INFO «moe» A measure of effectiveness (moe) represents a parameter whose value is critical for achieving the desired mission cost effectiveness. OMG Systems Modeling Language (SysML) 1.6 custom Stereotype, user defined Stereotype «moe» non-normative, Measure of Effectiveness
INFO «nonStreaming» Used for activities that accept inputs only when they start, and provide outputs only when they finish. The activity has no streaming parameters. OMG Systems Modeling Language (SysML) 1.6 Activity «nonStreaming» non-normative
INFO «objectiveFunction» An objective function (aka optimization or cost function) is used to determine the overall value of an alternative in terms of weighted criteria and/or moe's. OMG Systems Modeling Language (SysML) 1.6 custom Stereotype, user defined Stereotype «objectiveFunction», «moe» non-normative, objective function, Measure of Effectiveness
CONSTRAINT «performanceRequirement»: satisfied by a value property. OMG Systems Modeling Language (SysML) 1.6 ExtendedRequirement, AbstractRequirement, «performanceRequirement», value property, MD:ValueProperty requirements engineering
CONSTRAINT «physicalRequirement»: satisfied by a structural element. OMG Systems Modeling Language (SysML) 1.6 ExtendedRequirement, AbstractRequirement, «performanceRequirement», Block, part property, MD:PartProperty requirements engineering
INFO «Refine» Abstraction Specifies a refinement relationship between model elements at different semantic levels, such as analysis and design. The mapping specifies the relationship between the two elements or sets of elements. The mapping ... Unified Modeling Language 2.5.1 Refine, Stereotype, UML StandardProfile
INFO «streaming» Used for activities that can accept inputs or provide outputs after they start and before they finish. The activity has at least one streaming parameter. OMG Systems Modeling Language (SysML) 1.6 Activity «streaming» non-normative
EXAMPLE, INFO “BlackBox” for the purpose of this example, refers to how the subject system (HybridSUV block) interacts only with outside elements, without revealing any interior detail. OMG Systems Modeling Language (SysML) 1.6 UseCase::subject HSUV sample problem black box