abstract QoSontology = MidLevelOntology, Engineering ** {

  --  To exit a function or application without saving 
  -- any data that has been changed.
  fun Abort : Class ;
  fun Abort_Class : SubClass Abort ComputerProcess ;

  -- This is a subclass of 
  -- TimingRequirementAttribute, which includes Instrument_AbstractionLevel, 
  -- Method_AbstractionLevel, Object_AbstractionLevel, Task_AbstractionLevel,
  -- and TaskGroup_AbstractionLevel.
  fun AbstractionLevelAttribute : Class ;
  fun AbstractionLevelAttribute_Class : SubClass AbstractionLevelAttribute TimingRequirementAttribute ;

  -- (AddressFn ?FILE) returns as its value the 
  -- physical address of the ComputerFile ?FILE.
  fun AddressFn : El ComputerFile -> Ind PhysicalAddress ;

  -- An instance of the class 
  -- RealtimeSystem has Initiation_DesignPattern if it consists of 
  -- sensors connected to a software module that filters data from the 
  -- sensors and sends the filtered data to another software module that 
  -- evaluates the filtered data and sends decisions to a subsystem. 
  -- The design pattern is a data source that produces a data stream for 
  -- a data handler. The data source is typically a periodically sampled 
  -- collection of sensors. The data stream's size may vary and is 
  -- unbounded. Data may be either homogeneous or heterogeneous. The 
  -- workload per data element for homogeneous data is constant. The 
  -- workload per data element for heterogeneous data is a function of 
  -- each element type. There is one deadline for real_time situation 
  -- assessment systems. It is the upper bound on the time to process 
  -- all elements in the data stream once.
  fun Assessment_DesignPattern : Class ;
  fun Assessment_DesignPattern_Class : SubClass Assessment_DesignPattern DesignPatternAttribute ;

  -- A program which is started 
  -- automatically, as opposed to an application started in response to 
  -- some condition becoming true.
  fun AutomaticApplication : Class ;
  fun AutomaticApplication_Class : SubClass AutomaticApplication ComputerProgram ;

  -- Berkeley Software Distribution (UNIX), 
  -- a version of Unix distributed by the University of California at Berkeley. Widely 
  -- used as a standard for early versions of Unix and Unix software libraries.
  fun BerkeleySoftwareDistribution : Class ;
  fun BerkeleySoftwareDistribution_Class : SubClass BerkeleySoftwareDistribution OperatingSystem ;

  -- The measurement of the speed of data 
  -- transfer in a communications system.
  fun BitsPerSecond : Class ;

  -- A network in which all nodes are connected 
  -- to a single wire (the bus) that has two endpoints. Ethernet 10Base_2 
  -- and 10Base_5 networks, for example, are bus networks. Other common 
  -- network types include StarNetworks and RingNetworks.
  fun BusNetwork : Class ;
  fun BusNetwork_Class : SubClass BusNetwork LAN ;

  -- CPU (Central Processing Unit) is the computing part 
  -- of the computer.
  fun CPU : Class ;
  fun CPU_Class : SubClass CPU (both ComputerComponent ComputerHardware) ;

  -- (CPUUtilizationFn ?PROGRAM) refers to 
  -- the percentage of time the CPU is used by an application ?PROGRAM.
  fun CPUUtilizationFn : El ComputerProgram -> Ind ConstantQuantity ;

  -- A subclass of 
  -- TimingRequirementAttribute, which includes
  -- MultipleRequirement_Complexity and SingleRequirement_Complexity.
  fun ComplexityAttribute : Class ;
  fun ComplexityAttribute_Class : SubClass ComplexityAttribute TimingRequirementAttribute ;

  -- Instances of ComputationalSystems 
  -- include instances of SoftwareSystems, HardwareSystems, and 
  -- ComputerNetworks.
  fun ComputationalSystem : Class ;
  fun ComputationalSystem_Class : SubClass ComputationalSystem Product ;

  -- A general_purpose machine that processes 
  -- data according to a set of instructions that are stored internally 
  -- either temporarily or permanently.
  fun Computer : Class ;
  fun Computer_Class : SubClass Computer ElectricDevice ;

  -- An instance of ComputerComponent is a 
  -- piece of computer hardware that has measurable performance characteristics 
  -- in terms of different units. Components include hard drives, the performance
  -- of which can be measured in terms of BitsPerSecond required to transfer data 
  -- to and from the drive, network adapters, the performance of which can be 
  -- measured by PacketsPerSecond units of data transfered to and from the adapter, 
  -- and other common components like ComputerMemory and CentralProcessingUnit.
  fun ComputerComponent : Class ;
  fun ComputerComponent_Class : SubClass ComputerComponent ComputerHardware ;

  -- The term ComputerData refers to files 
  -- and databases, text documents, and images.
  fun ComputerData : Class ;
  fun ComputerData_Class : SubClass ComputerData ContentBearingObject ;

  -- This is the class of catalogs that 
  -- identify and locate instances of ComputerFiles. The catalog's entries 
  -- consist of at least ComputerFile names and a physical address on a memory
  -- device of the ComputerFile or an index (e.g., file descriptor) into a 
  -- table of ComputerFile physical addresses. ComputerDirectories are thus 
  -- collections of data elements and must be named and stored on memory devices, 
  -- hence, ComputerDirectory is a subset of ComputerFile. ComputerDirectory folders contain only files and other folders
  fun ComputerDirectory : Class ;
  fun ComputerDirectory_Class : SubClass ComputerDirectory ComputerFile ;

  fun ComputerFile_ComputerData : SubClass ComputerFile ComputerData ;

  -- The hardware is the physical part of 
  -- a computer system.
  fun ComputerHardware : Class ;
  fun ComputerHardware_Class : SubClass ComputerHardware EngineeringComponent ;

  -- A peripheral device that generates 
  -- input for the computer such as a keyboard, scanner, or mouse.
  fun ComputerInputDevice : Class ;
  fun ComputerInputDevice_Class : SubClass ComputerInputDevice ComputerHardware ;

  -- The EnglishLanguage computer's workspace (physically, 
  -- a collection of RAM chips). It is an important resource, since it 
  -- determines the size and number of programs that can be run at the 
  -- same time, as well as the amount of data that can be processed 
  -- instantly.
  fun ComputerMemory : Class ;
  fun ComputerMemory_Class : SubClass ComputerMemory (both ComputerComponent ComputerHardware) ;

  -- The network includes the network 
  -- operating system in the client and server machines, the cables 
  -- connecting them and all supporting hardware in between such as 
  -- bridges, routers and switches.
  fun ComputerNetwork : Class ;
  fun ComputerNetwork_Class : SubClass ComputerNetwork (both ComputationalSystem RealtimeSystem) ;

  -- Any peripheral that presents 
  -- output from the computer, such as a screen or printer.
  fun ComputerOutputDevice : Class ;
  fun ComputerOutputDevice_Class : SubClass ComputerOutputDevice ComputerHardware ;

  -- A word or code used to serve as a security 
  -- measure against unauthorized access to data. It is normally managed by the 
  -- operating system or DBMS.
  fun ComputerPassword : Class ;
  fun ComputerPassword_Class : SubClass ComputerPassword SymbolicString ;

  -- An instance of ComputerPath is a series 
  -- of programs that connects input devices, typically sensors, to output 
  -- devices, typically actuators.
  fun ComputerPath : Class ;
  fun ComputerPath_Class : SubClass ComputerPath ComputerData ;

  -- The class of all attributes that are 
  -- specific to ComputerPaths.
  fun ComputerPathAttribute : Class ;
  fun ComputerPathAttribute_Class : SubClass ComputerPathAttribute SoftwareAttribute ;

  -- An instance of ComputerProcess is a 
  -- process which manipulates data in the computer.
  fun ComputerProcess : Class ;
  fun ComputerProcess_Class : SubClass ComputerProcess InternalChange ;

  -- A collection of data, presented in a preformatted 
  -- manner.
  fun ComputerReport : Class ;
  fun ComputerReport_Class : SubClass ComputerReport ComputerData ;

  -- One element of hardware, software or data 
  -- that is part of a larger system. For example, network resources are the 
  -- available servers and printers in the network. Software resources can be 
  -- programs, utilities or even smaller elements within a program. Data 
  -- resources are the files and databases that can be accessed.
  fun ComputerResource : Class ;
  fun ComputerResource_Class : SubClass ComputerResource ComputationalSystem ;

  -- A ComputerProcess which attempts to 
  -- comply with a user's request.
  fun ComputerResponse : Class ;
  fun ComputerResponse_Class : SubClass ComputerResponse ComputerProcess ;

  -- An attribute which describes status of the 
  -- Computer, such as HostDown, HostReady.
  fun ComputerStatus : Class ;
  fun ComputerStatus_Class : SubClass ComputerStatus RelationalAttribute ;

  -- In a multitasking environment, an 
  -- independently running program or subprogram. Each task is assigned 
  -- a task number.
  fun ComputerTask : Class ;
  fun ComputerTask_Class : SubClass ComputerTask ComputerProcess ;

  -- A ComputerOutputDevice for displaying
  -- information on some sort of screen or other reusable output surface. This
  -- is contrasted with a Printer, which places a substance on a surface
  -- that is for practical purposes, permanent.
  fun ComputerTerminal : Class ;
  fun ComputerTerminal_Class : SubClass ComputerTerminal ComputerOutputDevice ;

  -- Any individual who interacts with a 
  -- computer.
  fun ComputerUser : Class ;
  fun ComputerUser_Class : SubClass ComputerUser CognitiveAgent ;

  -- This attribute applies to 
  -- real_time systems that are designed and implemented so that the system 
  -- can adapt by replicating the system components and executing them 
  -- concurrently.
  fun Concurrency_FormOfAdaptation : Class ;
  fun Concurrency_FormOfAdaptation_Class : SubClass Concurrency_FormOfAdaptation FormOfAdaptationAttribute ;

  -- A Program which is started inside 
  -- an Xterm or other console.
  fun ConsoleApplication : Class ;
  fun ConsoleApplication_Class : SubClass ConsoleApplication ComputerProgram ;

  -- The attribute which denotes that the 
  -- path type is continuous, as opposed to transient or quasiconstinuous 
  -- paths. A continuous path handles a stream of data arriving at a comment 
  -- of rate.
  fun ContinuousPath : Class ;
  fun ContinuousPath_Class : SubClass ContinuousPath ComputerPathAttribute ;

  -- Encoding data to take up less storage space.
  fun DataCompression : Class ;
  fun DataCompression_Class : SubClass DataCompression ComputerProcess ;

  -- A process of copying the document, record or 
  -- image being worked on onto a storage medium. Saving updates the file by 
  -- writing the data that currently resides in memory (RAM) onto disk or tape. 
  -- Most applications prompt the user to save data upon exiting.
  fun DataSaving : Class ;
  fun DataSaving_Class : SubClass DataSaving ComputerProcess ;

  -- A device or part of the computer that 
  -- receives data.
  fun DataSink : Class ;
  fun DataSink_Class : SubClass DataSink ComputerInputDevice ;

  -- A subclass of ComputerProcesses which 
  -- send data over a computer channel or bus.
  fun DataTransfer : Class ;
  fun DataTransfer_Class : SubClass DataTransfer ComputerProcess ;

  -- A set of related files that is created and 
  -- managed by a database management system (DBMS).
  fun Database : Class ;
  fun Database_Class : SubClass Database ComputerData ;

  -- An instance of RealtimeSystem 
  -- is described as Dependent_TaskRelation if it depends on at least one 
  -- other function in the system, that is, its correct execution depends on 
  -- the input from another function, the execution state of another function, 
  -- or the acceptance of its outputs by another function.
  fun Dependent_TaskRelation : Ind TaskRelationAttribute ;

  -- This is a subclass of 
  -- RealtimeSystemAttribute, which includes Guidance_DesignPattern, 
  -- Initiation_DesignPattern, and Assessment_DesignPattern.
  fun DesignPatternAttribute : Class ;
  fun DesignPatternAttribute_Class : SubClass DesignPatternAttribute RealtimeSystemAttribute ;

  -- The attribute which denotes that 
  -- the data stream is conceived as a stream of one datum after another, and 
  -- each datum or identifiable group of data is separated by a constant of 
  -- time.
  fun DeterministicDataStream : Class ;
  fun DeterministicDataStream_Class : SubClass DeterministicDataStream ComputerPathAttribute ;

  -- The attribute which denotes that the 
  -- path data stream type is dynamic, i.e. the time changes but the data 
  -- stream follows a pattern.
  fun DynamicDataStream : Class ;
  fun DynamicDataStream_Class : SubClass DynamicDataStream ComputerPathAttribute ;

  -- The class of attributes which 
  -- correspond to environment variables. Environment variables are defined 
  -- outside of a ComputerProgram, unlike ordinary variables that are 
  -- defined in the source code of the ComputerProgram. Typically, the 
  -- environment variable stores some value that many if not all 
  -- ComputerProgams will need when they execute. An example is the
  -- environment variable PATH under Unix_like operating systems that stores 
  -- the ComputerDirectories where executable ComputerPrograms can be found. 
  -- Another example is the environment variable CLASSPATH for Java programs, 
  -- which stores the directory where Java class files can be found that will be 
  -- needed by any ComputerProgram written in Java.
  fun EnvironmentSoftwareAttribute : Class ;
  fun EnvironmentSoftwareAttribute_Class : SubClass EnvironmentSoftwareAttribute RelationalAttribute ;

  -- An instant in time that is arbitrarily selected as a point of reference.
  fun Epoch : Class ;
  fun Epoch_Class : SubClass Epoch TimePoint ;

  -- Able to be run in its current format.
  fun Executable : Ind RelationalAttribute ;

  -- The class of all messages to a resource 
  -- management program from one of its processes.
  fun Feedback : Class ;
  fun Feedback_Class : SubClass Feedback ContentBearingObject ;

  -- An attribute that applies to a 
  -- RealtimeSystem just in case a fixed percentage of requirements 
  -- is met.
  fun Firm_Strictness : Class ;
  fun Firm_Strictness_Class : SubClass Firm_Strictness StrictnessAttribute ;

  -- A subclass of 
  -- RealtimeSystemAttribute, which includes Precision_FormOfAdaptation, 
  -- Slack_FormOfAdaptation, Concurrency_FormOfAdaptation, and 
  -- ResourceAllocation_FormOfAdaptation.
  fun FormOfAdaptationAttribute : Class ;
  fun FormOfAdaptationAttribute_Class : SubClass FormOfAdaptationAttribute RealtimeSystemAttribute ;

  -- Instances of RealtimeSystems 
  -- are described as systems with Guidance_DesignPattern if they consist 
  -- of sensors connected to a software module that filters data from the 
  -- sensors and sends the filtered data to a software module that evaluates 
  -- the filtered data and sends instructions to a software module that 
  -- commands actuators. The design pattern is an event source that produces 
  -- events and a data source that produces data, both executing in parallel 
  -- and handled by a single event_driven periodic data handler. The two 
  -- separate input streams have fundamentally different characteristics. 
  -- The event stream is necessarily asychronous, or transient. Once an 
  -- event is sensed, the handler accepts data from the data stream, which 
  -- has an invariant cycle time. There are two deadlines for a real_time 
  -- guidance system. The period deadline is the time to process all elements 
  -- in the data stream once and generate an actuator command. The action 
  -- completion deadline is the time to guide the actuator to completion of 
  -- the action.
  fun Guidance_DesignPattern : Class ;
  fun Guidance_DesignPattern_Class : SubClass Guidance_DesignPattern DesignPatternAttribute ;

  -- The primary computer storage medium, which 
  -- is made of one or more aluminum or glass platters, coated with a 
  -- ferromagnetic material. Most hard disks are fixed disks, which are 
  -- permanently sealed in the drive.
  fun HardDiskDrive : Class ;
  fun HardDiskDrive_Class : SubClass HardDiskDrive (both ComputerComponent ComputerHardware) ;

  -- An attribute that applies to a 
  -- RealtimeSystem just in case all deadlines are met.
  fun Hard_Strictness : Class ;
  fun Hard_Strictness_Class : SubClass Hard_Strictness StrictnessAttribute ;

  -- The class of hardware systems is the 
  -- connection of three types of physical modules: instances of 
  -- ComputerProcessor(s), ComputerMemory, and ComputerNetwork. 
  -- ComputerProcessors execute instructions from ComputerPrograms, 
  -- which usually include instructions to read and write data from 
  -- memory, and send data via instances of ComputerNetworks.
  fun HardwareSystem : Class ;
  fun HardwareSystem_Class : SubClass HardwareSystem (both ComputationalSystem (both ComputerHardware RealtimeSystem)) ;

  -- Used to indicate that a ComputationalSystem 
  -- has a high priority.
  fun HighPriority : Ind PriorityAttribute ;

  -- An attribute which applies to a computer that ceases to 
  -- operate due to hardware or software failure.
  fun HostDown : Ind ComputerStatus ;

  -- An attribute which applies to a computer that is 
  -- functional, operating properly, and ready to receive work requests.
  fun HostReady : Ind ComputerStatus ;

  -- An attribute that applies to a 
  -- RealtimeSystem just in case the strictness of the system is a 
  -- combination of Hard/Firm/Soft_Strictness with Importance_Strictness 
  -- or a combination of Utility_Strictness with Importance_Strictness.
  fun Hybrid_Strictness : Class ;
  fun Hybrid_Strictness_Class : SubClass Hybrid_Strictness StrictnessAttribute ;

  -- An instance of the class 
  -- RealtimeSystem shows Hybrid_SystemBehavior if it is 
  -- activated by transient events, i.e. it is executed at regular 
  -- intervals when activated, and is deactivated by action completion.
  fun Hybrid_SystemBehavior : Class ;
  fun Hybrid_SystemBehavior_Class : SubClass Hybrid_SystemBehavior SystemBehaviorAttribute ;

  -- The Internet Protocol address, a numeric address such as 123.231.32.2 that 
  -- the domain name server translates into a domain name.
  fun IPAddress : Class ;
  fun IPAddress_Class : SubClass IPAddress PhysicalAddress ;

  -- A picture (graphic) stored in a particular 
  -- coding scheme and stored as a file. Note that this can include vector as 
  -- well as raster images. Raster images will entail a particular number of 
  -- horizontal and vertical pixels. Vector images will not entail a 
  -- particular size or resolution.
  fun ImageFile : Class ;
  fun ImageFile_Class : SubClass ImageFile ComputerData ;

  -- An attribute that applies to a 
  -- RealtimeSystem just in case it is designed and implemented to meet 
  -- the more important requirements first.
  fun Importance_Strictness : Class ;
  fun Importance_Strictness_Class : SubClass Importance_Strictness StrictnessAttribute ;

  -- An instance of RealtimeSystem 
  -- is described as Independent_TaskRelation if its correct execution 
  -- does not depend on the inputs from any other function, the execution state 
  -- of any other function, or the acceptance of its outputs by any other 
  -- function.
  fun Independent_TaskRelation : Class ;
  fun Independent_TaskRelation_Class : SubClass Independent_TaskRelation TaskRelationAttribute ;

  -- The function which returns as its value 
  -- the initial profile of the program, i.e. a report of its execution 
  -- characteristics.
  fun InitialProfileFn : El ComputerProgram -> Ind ProcessState ;

  -- An instance of the class 
  -- RealtimeSystem has Initiation_DesignPattern if it consists of 
  -- one software module and the actuators it commands. The design pattern 
  -- is an event source which produces events for an event handler. The 
  -- event source is typically an evaluate_and_decide software module. 
  -- The event stream is necessarily asychronous, or transient. The arrival 
  -- rate of events may vary and is unbounded. Events may be either 
  -- homogeneous or heterogeneous. The workload per event for homogeneous 
  -- events is constant. The workload per event for heterogeneous events 
  -- is a function of each event type. There is one deadline for real_time 
  -- action initiation systems. It is the upper bound on the time to 
  -- generate a command for the actuator.
  fun Initiation_DesignPattern : Class ;
  fun Initiation_DesignPattern_Class : SubClass Initiation_DesignPattern DesignPatternAttribute ;

  -- The attribute Instrument_AbstractionLevel is the lowest level of abstraction, 
  -- which can be used to describe a real_time system or subsystem.
  fun Instrument_AbstractionLevel : Class ;
  fun Instrument_AbstractionLevel_Class : SubClass Instrument_AbstractionLevel AbstractionLevelAttribute ;

  -- A computer network that spans a relatively small 
  -- area. Most LANs are confined to a single building or group of buildings. 
  -- However, one LAN can be connected to other LANs over any distance via 
  -- telephone lines and radio waves. LAN A local_area network (LAN) whose topology is a ring. 
  -- That is, all of the nodes are connected in a closed loop. Messages 
  -- travel around the ring, with each node reading those messages addressed 
  -- to it.
  fun LAN : Class ;
  fun LAN_Class : SubClass LAN ComputerNetwork ;

  -- Used to indicate that a ComputationalSystem 
  -- has a low priority.
  fun LowPriority : Ind PriorityAttribute ;

  -- Each element of MeasuringPerformance 
  -- is an event of measuring the performance of an instance of ComputerComponent, 
  -- performed by a MonitoringProgram.
  fun MeasuringPerformance : Class ;
  fun MeasuringPerformance_Class : SubClass MeasuringPerformance ComputerProcess ;

  -- The attribute 
  -- Method_AbstractionLevel is the next to the lowest level of 
  -- abstraction that can be used to describe a real_time system or 
  -- subsystem. This is at the level of describing every callable 
  -- function (or method in an object_oriented language) implemented 
  -- in software.
  fun Method_AbstractionLevel : Class ;
  fun Method_AbstractionLevel_Class : SubClass Method_AbstractionLevel AbstractionLevelAttribute ;

  -- This command is to change the monitoring 
  -- for any component for which a componentDataID was sent on initial connection.
  fun MonitorApplicationCmd : Class ;
  fun MonitorApplicationCmd_Class : SubClass MonitorApplicationCmd MonitoringProgram ;

  -- This is the command to monitor any of the 
  -- generic components _ hard drive, network, cpu, memory, etc.
  fun MonitorComponentCmd : Class ;
  fun MonitorComponentCmd_Class : SubClass MonitorComponentCmd MonitoringProgram ;

  -- This is the command to get a list 
  -- of applications periodically.
  fun MonitorConnectivityCmd : Class ;
  fun MonitorConnectivityCmd_Class : SubClass MonitorConnectivityCmd MonitoringProgram ;

  -- A program which monitors performance 
  -- of an application, a component, etc.
  fun MonitoringProgram : Class ;
  fun MonitoringProgram_Class : SubClass MonitoringProgram ComputerProgram ;

  -- An attribute that describes 
  -- instances of RealtimeSystems which require multiple timing requirements, 
  -- both a bound for completion time for its transient behavior and a cycle 
  -- deadline for its periodic behavior.
  fun MultipleRequirement_Complexity : Class ;
  fun MultipleRequirement_Complexity_Class : SubClass MultipleRequirement_Complexity ComplexityAttribute ;

  -- The running of two or more programs in one 
  -- computer at the same time. The number of programs that can be effectively 
  -- multitasked depends on the type of multitasking performed (preemptive vs 
  -- cooperative), CPU speed and memory and disk capacity.
  fun Multitasking : Class ;
  fun Multitasking_Class : SubClass Multitasking ComputerProcess ;

  -- A network adapter, also known as a Network 
  -- Interface Card or NIC, is a physical device installed in a computer on its 
  -- system bus. Its purpose is to connect to a specific type of network,
  -- usually an ethernet or a token ring network.
  fun NetworkAdapter : Class ;
  fun NetworkAdapter_Class : SubClass NetworkAdapter ComputerComponent ;

  -- Network resources are the available 
  -- servers and printers in the network.
  fun NetworkResource : Class ;
  fun NetworkResource_Class : SubClass NetworkResource ComputerResource ;

  -- The attribute 
  -- Object_AbstractionLevel is immediately above the attribute 
  -- Method_AbstractionLevel and can be used to describe a real_time 
  -- system or subsystem. This is at the level of describing every software 
  -- object that can be created from a class together with its data structures 
  -- and methods (which define the interface for manipulating the object).
  fun Object_AbstractionLevel : Class ;
  fun Object_AbstractionLevel_Class : SubClass Object_AbstractionLevel AbstractionLevelAttribute ;

  -- The master control program that runs the 
  -- computer. It is the first program loaded when the computer is turned on, 
  -- and its main part, called the kernel, resides in memory at all times. It 
  -- may be developed by the vendor of the computer it's running in or by a 
  -- third party.
  fun OperatingSystem : Class ;
  fun OperatingSystem_Class : SubClass OperatingSystem SoftwareSystem ;

  -- Optimization means finding the best solution according 
  -- to a set of criteria. For a computer program, an optimal solution would be the 
  -- fastest program (according to some benchmark) or the smallest program.
  fun Optimization : Class ;
  fun Optimization_Class : SubClass Optimization ProcessTask ;

  -- A block of data used for transmission in packet 
  -- switched systems.
  fun Packet : Class ;
  fun Packet_Class : SubClass Packet ComputerData ;

  -- The rate or speed of Packet_Networks 
  -- transferred in a second.
  fun PacketsPerSecond : Ind CompositeUnitOfMeasure ;

  -- The attribute which denotes that 
  -- the path importance is defined by the dynamic library procedure 
  -- pathImportanceFunction. This functions passes arguments for priority 
  -- and current time and returns an integer that represents importance.
  fun PathImportanceFunction : Ind ComputerPathAttribute ;

  -- An instance of the class 
  -- RealtimeSystem is described as a system with Periodic_SystemBehavior 
  -- when it is activated at regular intervals.
  fun Periodic_SystemBehavior : Class ;
  fun Periodic_SystemBehavior_Class : SubClass Periodic_SystemBehavior SystemBehaviorAttribute ;

  -- The collection of all addresses which 
  -- identify a location of a ComputerFile.
  fun PhysicalAddress : Class ;
  fun PhysicalAddress_Class : SubClass PhysicalAddress SymbolicString ;

  fun Precision_FormOfAdaptation : Class ;
  fun Precision_FormOfAdaptation_Class : SubClass Precision_FormOfAdaptation FormOfAdaptationAttribute ;
  -- A device that converts computer output into 
  -- printed images.
  fun Printer : Class ;
  fun Printer_Class : SubClass Printer ComputerOutputDevice ;

  -- A class of attributes which describe 
  -- priorities of ComputationalSystems.
  fun PriorityAttribute : Class ;
  fun PriorityAttribute_Class : SubClass PriorityAttribute RelationalAttribute ;

  -- An attribute that denotes the failure of the Process to achieve 
  -- its goal.
  fun ProcessFailure : Ind ProcessStatus ;

  -- The class of all the information required 
  -- for a ComputerProgram to run on a processor. It is a vector that 
  -- contains a pointer to the next program instruction to be executed as well 
  -- as the values of all intermediate and defined variables, the state of the 
  -- processor executing the program, and the allocated address space among 
  -- other data.
  fun ProcessState : Class ;
  fun ProcessState_Class : SubClass ProcessState ContentBearingObject ;

  -- A class of attributes. Each instance of ProcessStatus describes a 
  -- status of a Process, such as ProcessFailure, ProcessSuccess, etc.
  fun ProcessStatus : Class ;
  fun ProcessStatus_Class : SubClass ProcessStatus RelationalAttribute ;

  -- An attribute that denotes the success of the Process to achieve 
  -- its goal.
  fun ProcessSuccess : Ind ProcessStatus ;

  -- A function to be performed.
  fun ProcessTask : Class ;
  fun ProcessTask_Class : SubClass ProcessTask Abstract ;

  -- An attribute which applies to 
  -- computer paths which handle random events, which initiate a bounded 
  -- stream of data arriving at a comment of rate, which the path must 
  -- process.
  fun QuasicontinuousPath : Class ;
  fun QuasicontinuousPath_Class : SubClass QuasicontinuousPath ComputerPathAttribute ;

  -- A program started by a Resource 
  -- Management program, which determines if and where to start the 
  -- application.
  fun RM_StartApplication : Class ;
  fun RM_StartApplication_Class : SubClass RM_StartApplication ComputerProgram ;

  -- An computer_controlled system, the 
  -- correct operation of which depends on meeting specified timing 
  -- constraints.
  fun RealtimeSystem : Class ;
  fun RealtimeSystem_Class : SubClass RealtimeSystem ComputationalSystem ;

  -- The class of Attributes which 
  -- describe instances of the class RealtimeSystem.
  fun RealtimeSystemAttribute : Class ;
  fun RealtimeSystemAttribute_Class : SubClass RealtimeSystemAttribute RelationalAttribute ;

  -- The attribute which denotes that 
  -- a program can be restarted on the same host.
  fun ReplicationsOnSameHostOK : Ind SoftwareAttribute ;

  -- This attribute applies 
  -- to real_time systems that are designed and implemented so that the system 
  -- can adapt under the control of a resource allocation manager like Desiderata.
  fun ResourceAllocation_FormOfAdaptation : Class ;
  fun ResourceAllocation_FormOfAdaptation_Class : SubClass ResourceAllocation_FormOfAdaptation FormOfAdaptationAttribute ;

  -- The class of resource 
  -- management programs.
  fun ResourceManagementProgram : Class ;
  fun ResourceManagementProgram_Class : SubClass ResourceManagementProgram ComputerProgram ;

  -- The attribute which denotes that a program 
  -- can be restarted.
  fun Restartable : Ind SoftwareAttribute ;

  -- To use the same resource again.
  fun ReusingAResource : Class ;
  fun ReusingAResource_Class : SubClass ReusingAResource ComputerProcess ;

  fun RingNetwork : Class ;
  fun RingNetwork_Class : SubClass RingNetwork LAN ;
  -- SatisfyingRequirements covers cases of 
  -- finding a solution that satisfies necessary conditions.
  fun SatisfyingRequirements : Class ;
  fun SatisfyingRequirements_Class : SubClass SatisfyingRequirements ProcessTask ;

  -- The attribute which denotes that 
  -- an application can combine its input stream from different preceding 
  -- applications or devices for greater scalability.
  fun ScalabilityCombining : Ind SoftwareAttribute ;

  -- The attribute which denotes that 
  -- a program can split its output stream to different succeeding 
  -- applications or devices for greater scalability.
  fun ScalabilitySplitting : Ind SoftwareAttribute ;

  -- The attribute which denotes that the path is 
  -- scalable, i.e. the applications in the path can be replicated to meet 
  -- realtime QoS requirements.
  fun Scalable : Class ;
  fun Scalable_Class : SubClass Scalable ComputerPathAttribute ;

  -- Sensors include software that measures any 
  -- attribute of executing computer programs or collections of executing 
  -- programs, such as CPU utilization, aka load, memory utilization, I/O, 
  -- overall task performance, network load and latency, etc.
  fun Sensor : Class ;
  fun Sensor_Class : SubClass Sensor ComputerHardware ;

  -- A computer in a network shared by multiple users. 
  -- The term may refer to both the hardware and software or just the software 
  -- that performs the service.
  fun Server : Class ;
  fun Server_Class : SubClass Server ComputationalSystem ;

  -- A typically small instance of 
  -- ComputerProgram whose function is to end a typically larger
  -- instance of ComputerProgram.
  fun ShutdownBlock : Class ;
  fun ShutdownBlock_Class : SubClass ShutdownBlock ComputerProgram ;

  -- (ShutdownFn ?Program) returns an instance of 
  -- ShutdownBlock which contains the instructions to end ?PROGRAM.
  fun ShutdownFn : El ComputerProgram -> Ind ShutdownBlock ;

  -- An attribute that describes 
  -- instances of RealtimeSystems which require a single timing requirement,
  -- either a bound for completion time for systems with 
  -- Transient_SystemBehavior or cycle deadline for systems with 
  -- Periodic_SystemBehavior.
  fun SingleRequirement_Complexity : Class ;
  fun SingleRequirement_Complexity_Class : SubClass SingleRequirement_Complexity ComplexityAttribute ;

  -- The attribute Slack_FormOfAdaptation 
  -- applies to real_time systems that are designed and implemented with enough 
  -- resource overhead that the system can always adapt by utilizing the overhead 
  -- without complicated decision making.
  fun Slack_FormOfAdaptation : Class ;
  fun Slack_FormOfAdaptation_Class : SubClass Slack_FormOfAdaptation FormOfAdaptationAttribute ;

  -- An attribute that applies to a 
  -- RealtimeSystem just in case it maximizes the number of timing 
  -- requirements like deadlines that are met but does not guarantee that 
  -- all such requirements will be met or any fixed percentage of 
  -- requirements will be met.
  fun Soft_Strictness : Class ;
  fun Soft_Strictness_Class : SubClass Soft_Strictness StrictnessAttribute ;

  -- The class of all attributes that are 
  -- specific to SoftwareSystems.
  fun SoftwareAttribute : Class ;
  fun SoftwareAttribute_Class : SubClass SoftwareAttribute RelationalAttribute ;

  -- This is the class of mutually supportive 
  -- groups of instances of ComputerProgram for a single general purpose. 
  -- For example, a database management system is a collection of many instances
  -- of ComputerProgram that work together to store, retrieve, modify, and 
  -- delete data.
  fun SoftwareSystem : Class ;
  fun SoftwareSystem_Class : SubClass SoftwareSystem (both ComputationalSystem RealtimeSystem) ;

  -- The class of all instances of Solaris , a 
  -- unix_based operating system for Sun SPARC computers. It includes the 
  -- Open Look and Motif graphical user interfaces, OpenWindows (the Sun 
  -- version of X Windows), DOS and Windows Emulation, and ONC networking.
  fun Solaris : Class ;
  fun Solaris_Class : SubClass Solaris OperatingSystem ;

  -- A local_area network (LAN) that uses a star 
  -- topology in which all nodes are connected to a central computer.
  fun StarNetwork : Class ;
  fun StarNetwork_Class : SubClass StarNetwork LAN ;

  -- A typically small instance of ComputerProgram 
  -- (a sequence of instructions that will run on a computer) whose function is 
  -- to load and initialize a typically larger instance of ComputerProgram 
  -- and start it running.
  fun StartupBlock : Class ;
  fun StartupBlock_Class : SubClass StartupBlock ComputerProgram ;

  -- (StartupFn ?Program) returns an instance of 
  -- StartupBlock which contains the instructions to start the ?Program.
  fun StartupFn : El ComputerProgram -> Ind StartupBlock ;

  -- The attribute which denotes that 
  -- the time between data or groups of data changes according to no 
  -- discernible pattern.
  fun StochasticDataStream : Class ;
  fun StochasticDataStream_Class : SubClass StochasticDataStream ComputerPathAttribute ;

  -- This is a subclass of 
  -- TimingRequirementAttribute, which includes Hard_Strictness, 
  -- Firm_Strictness, Soft_Strictness, Importance_Strictness,
  -- Utility_Strictness, and Hybrid_Strictness
  fun StrictnessAttribute : Class ;
  fun StrictnessAttribute_Class : SubClass StrictnessAttribute TimingRequirementAttribute ;

  -- A subclass of 
  -- RealtimeSystemAttribute, which includes the following Attributes: 
  -- Periodic_SystemBehavior, Transient_SystemBehavior, and 
  -- Hybrid_SystemBehavior.
  fun SystemBehaviorAttribute : Class ;
  fun SystemBehaviorAttribute_Class : SubClass SystemBehaviorAttribute RealtimeSystemAttribute ;

  -- The attribute 
  -- TaskGroup_AbstractionLevel is immediately above the attribute 
  -- Task_AbstractionLevel and can be used to describe a real_time 
  -- system or subsystem This is at the level of describing groups of 
  -- tasks which are related or connected by the real_time systems and 
  -- are typically part of a concurrently executing path.
  fun TaskGroup_AbstractionLevel : Class ;
  fun TaskGroup_AbstractionLevel_Class : SubClass TaskGroup_AbstractionLevel AbstractionLevelAttribute ;

  -- This is a subclass of 
  -- RealtimeSystemAttribute, which includes Independent_TaskRelation 
  -- and Dependent_TaskRelation.
  fun TaskRelationAttribute : Class ;
  fun TaskRelationAttribute_Class : SubClass TaskRelationAttribute RealtimeSystemAttribute ;

  -- The attribute 
  -- Task_AbstractionLevel is immediately above the attribute 
  -- Object_AbstractionLevel and can be used to describe a real_time 
  -- system or subsystem. This is at the level of describing the major 
  -- tasks that are carried out by the real_time systems and are typically 
  -- executable as individual processes. The description of a task would 
  -- consist of listing all the software objects used to perform the task.
  fun Task_AbstractionLevel : Class ;
  fun Task_AbstractionLevel_Class : SubClass Task_AbstractionLevel AbstractionLevelAttribute ;

  -- A subclass of 
  -- RealtimeSystemAttribute which includes ComplexityAttribute, 
  -- StrictnessAttribute, and AbstractionLevelAttribute.
  fun TimingRequirementAttribute : Class ;
  fun TimingRequirementAttribute_Class : SubClass TimingRequirementAttribute RealtimeSystemAttribute ;

  -- An attribute which applies to computer 
  -- paths which handle random events.
  fun TransientPath : Class ;
  fun TransientPath_Class : SubClass TransientPath ComputerPathAttribute ;

  -- An instance of the class 
  -- RealtimeSystem shows Transient_SystemBehavior when it is 
  -- activated by sporadic events.
  fun Transient_SystemBehavior : Class ;
  fun Transient_SystemBehavior_Class : SubClass Transient_SystemBehavior SystemBehaviorAttribute ;

  -- A UniformResourceIdentifier 
  -- (URI) is a compact string of characters for identifying an abstract or 
  -- physical resource. A URI can be further classified as a locator, a name, 
  -- or both (source: http://www.ietf.org/rfc/rfc2396.txt).
  fun UniformResourceIdentifier : Class ;
  fun UniformResourceIdentifier_Class : SubClass UniformResourceIdentifier ContentBearingObject ;

  -- The term UniformResourceLocator 
  -- (URL) refers to the subset of URI that identify resources via a 
  -- representation of their primary access mechanism (e.g., their network 
  -- location), rather than identifying the resource by name or by some other 
  -- attribute(s) of that resource (source: http://www.ietf.org/rfc/rfc2396.txt).
  fun UniformResourceLocator : Class ;
  fun UniformResourceLocator_Class : SubClass UniformResourceLocator UniformResourceIdentifier ;

  -- The term UniformResourceName (URN) 
  -- refers to the subset of URI that are required to remain globally unique 
  -- and persistent even when the resource ceases to exist or becomes 
  -- unavailable (source: http://www.ietf.org/rfc/rfc2396.txt).
  fun UniformResourceName : Class ;
  fun UniformResourceName_Class : SubClass UniformResourceName UniformResourceIdentifier ;

  -- The Unix epoch or point of reference is 00:00:00 UTC, 
  -- January 1, 1970.
  fun UnixEpoch : Ind Epoch ;

  -- An established relationship between a user and a 
  -- computer, network or information service. User accounts require a username and 
  -- password, and new user accounts are given a default set of permissions.
  fun UserAccount : Class ;
  fun UserAccount_Class : SubClass UserAccount ContentBearingObject ;

  -- The name a person uses to identify himself or herself 
  -- when logging onto a computer system or online service.
  fun UserName : Class ;
  fun UserName_Class : SubClass UserName SymbolicString ;

  -- A request made by a ComputerUser, such as 
  -- looking up a customer record.
  fun UserRequest : Class ;
  fun UserRequest_Class : SubClass UserRequest ComputerProcess ;

  -- A ComputerProcess which requires access to a 
  -- ComputerResource.
  fun UsingAResource : Class ;
  fun UsingAResource_Class : SubClass UsingAResource ComputerProcess ;

  -- A program that performs a specific task related to the 
  -- management of computer functions, resources, or files. Utility programs range 
  -- from the simple to the sophisticated, and many programmers specialize in producing 
  -- and distributing them as shareware. There are utilities that perform file and 
  -- directory management, data compression, disk defragmentation and repair, system 
  -- diagnostics, graphics viewing, and system security, for example. Many utilities 
  -- are written as memory_resident programs meant to serve as adjuncts to operating 
  -- systems. Many operating systems incorporate such popular utility functions as 
  -- undeleting, password protection, memory management, virus protection, and file 
  -- compression.
  fun Utility : Class ;
  fun Utility_Class : SubClass Utility ComputerProgram ;

  -- An attribute that applies to a 
  -- RealtimeSystem just in case it is designed and implemented to use 
  -- a utility_computing function, which is applied to competing timing 
  -- requirements to determine which should be met because meeting the 
  -- requirement produces higher utility as defined by the function.
  fun Utility_Strictness : Class ;
  fun Utility_Strictness_Class : SubClass Utility_Strictness StrictnessAttribute ;

  fun abstractionLevel : El RealtimeSystem -> El AbstractionLevelAttribute -> Formula ;

  -- (bandwidthOf ?NET ?BANDWIDTH) holds if 
  -- ?BANDWIDTH is the amount of data which can be sent through an instance 
  -- of a ComputerNetwork ?NET, measured in bits per second.
  fun bandwidthOf : El ComputerNetwork -> El BitsPerSecond -> Formula ;

  -- (batchInterArrival ?PATH ?TIME) 
  -- holds if ?TIME is the maximum allowable time between processing of a 
  -- particular element of a continuous or quasicontinuous path's data 
  -- stream in successive cycles.
  fun batchInterArrival : El ComputerPath -> El TimeDuration -> Formula ;

  -- (batchLatency ?PATH ?TIME)holds if ?TIME 
  -- is the maximum allowed latency for all cycles of a quasicontinuous path.
  fun batchLatency : El ComputerPath -> El TimeDuration -> Formula ;

  -- (benchmarkPerformance ?SYSTEM 
  -- ?TEST ?NUMBER) holds if ?NUMBER is a benchmark for measuring the performance 
  -- of an instance of a ComputationalSystem.
  fun benchmarkPerformance : El ComputationalSystem -> El MonitoringProgram -> El Quantity -> Formula ;

  -- (collectRate ?System ?Period) holds if ?Period is 
  -- the period at which ComputationalSystem ?System collects data.
  fun collectRate : El ComputationalSystem -> El TimeDuration -> Formula ;

  -- (commandLineArguments ?PROGRAM ?LIST) means that the application ?PROGRAM requires command line 
  -- arguments, as specified in ?LIST.
  fun commandLineArguments : El ComputerProgram -> El List -> Formula ;

  -- (complexity ?System ?Attribute) holds if 
  -- ?Attribute is a TimingRequirementAttribute which describes the 
  -- RealtimeSystem ?System.
  fun complexity : El RealtimeSystem -> El TimingRequirementAttribute -> Formula ;

  -- (componentDataID ?TIME ?COMPONENT ?INSTANCE 
  -- ?UNIT ?NUMBER) holds if ?INSTANCE is an instance of ?COMPONENT, identified by 
  -- IDNumber ?NUMBER, and whose performance is measured by a UnitOfMeasure_ComputerPerformance ?UNIT. The timestamp ?TIME identifies the time when this 
  -- information was created.
  fun componentDataID: El TimePosition -> Desc ComputerComponent -> El ComputerComponent -> El UnitOfMeasure -> El SymbolicString -> Formula ;

  -- (computerResponseTo ?Response ?Request) means that 
  -- ?Response is a ComputerResponse to the UserRequest ?Request.
  fun computerResponseTo : El ComputerResponse -> El UserRequest -> Formula ;

  -- (computerRunning ?Process ?Computer) 
  -- means that the ComputerProcess ?Process is running on ?Computer.
  fun computerRunning : El ComputerProcess -> El Computer -> Formula ;

  -- (criticalityLevel ?PROGRAM ?INTEGER) 
  -- holds just in case ?INTEGER indicates the relative priority of ?PROGRAM 
  -- with respect to other applications within the SoftwareSystem.
  fun criticalityLevel : El ComputerProgram -> El Integer -> Formula ;

  -- (dataID ?PROGRAM ?NUMBER) holds if ?NUMBER is a small 
  -- number associated with an instance of MonitoringProgram.
  fun dataID : El MonitoringProgram -> El SymbolicString -> Formula ;

  -- The data being processed during a ComputerProcess.
  fun dataProcessed : El ComputerProcess -> El ComputerData -> Formula ;

  -- (dataStreamSlack ?PATH ?N) means that 
  -- a continuous or quasicontinuous path ?PATH should be able to process ?N 
  -- additional data items at any time.
  fun dataStreamSlack : El ComputerPath -> El PositiveInteger -> Formula ;

  -- (defaultNetwork ?SYSTEM ?NET) holds if 
  -- ?NET is the default network of the HardwareSystem ?SYSTEM.
  fun defaultNetwork : El HardwareSystem -> El ComputerNetwork -> Formula ;

  -- if the dependency type is StartupBlock, 
  -- then (dependencyDelay ?PROGRAM ?TIME) means that the application 
  -- ?PROGRAM can only be started after a dependency delay of ?TIME after the 
  -- startup of the application. If the dependency type is ShutdownBlock, then 
  -- (dependencyDelay ?PROGRAM ?TIME) means that the application ?PROGRAM can 
  -- only be stopped after a dependency delay of ?TIME after the application 
  -- is stopped.
  fun dependencyDelay : El ComputerProgram -> El TimeDuration -> Formula ;

  -- (dependencyType ?PROGRAM ?TYPE) means 
  -- that ?PROGRAM has a dependency type ?TYPE, where ?TYPE can be either 
  -- StartupBlock or ShutdownBlock.
  fun dependencyType: El ComputerProgram -> Desc ComputerProgram -> Formula ;

  -- (designPattern ?System ?Attribute) holds 
  -- if ?Attribute is a DesignPatternAttribute which describes the 
  -- RealtimeSystem ?System.
  fun designPattern : El RealtimeSystem -> El DesignPatternAttribute -> Formula ;

  -- (directoryOf ?FILE ?DIRECTORY) means that 
  -- the ComputerFile ?FILE is in the ComputerDirectory ?DIRECTORY.
  fun directoryOf : El ComputerFile -> El ComputerDirectory -> Formula ;

  -- (environmentAttributes ?Program ?Attribute) holds if ?Attribute is an EnvironmentSoftwareAttribute 
  -- which describes the ComputerProgram ?Program.
  fun environmentAttributes : El ComputerProgram -> El EnvironmentSoftwareAttribute -> Formula ;

  -- (formOfAdaptation ?System ?Attribute) 
  -- holds if ?Attribute is a FormOfAdaptationAttribute which describes the 
  -- RealtimeSystem ?System.
  fun formOfAdaptation : El RealtimeSystem -> El FormOfAdaptationAttribute -> Formula ;

  -- Granularity is a sub_property of the 
  -- timing requirements property of real_time systems. Granularity is 
  -- defined by how a timing requirement is specified in units of time.
  fun granularity : El RealtimeSystem -> El TimeDuration -> Formula ;

  -- (hardwareType ?TYPE ?COMPUTER) means that 
  -- TYPE represents the computer vendor model name, as well as the version 
  -- of the product.
  fun hardwareType : El SymbolicString -> El Computer -> Formula ;

  -- (hasAccount ?User ?Account) holds if ?User is 
  -- assigned the UserAccount ?Account.
  fun hasAccount : El ComputerUser -> El UserAccount -> Formula ;

  -- (hasDependency ?PROGRAM1 ?PROGRAM2) 
  -- holds if ?PROGRAM1 is dependent on the application ?PROGRAM2.
  fun hasDependency : El ComputerProgram -> El ComputerProgram -> Formula ;

  -- (heartBeatRate ?Program ?Period) holds if 
  -- ?Period is the period at which the ComputerProgram ?Program sends its heartbeat 
  -- to a monitoring process.
  fun heartBeatRate : El ComputerProgram -> El TimeDuration -> Formula ;

  -- Interference on an analog line caused by a variation 
  -- of a signal from its reference timing slots. Jitter can cause problems in the receipt 
  -- of data and any subsequent processing of that data.
  fun hostJitter : El Computer -> El ConstantQuantity -> Formula ;

  -- (hostOf ?SYSTEM ?COMPUTER) means that ?COMPUTER 
  -- is the host of the computational system ?SYSTEM.
  fun hostOf : El ComputationalSystem -> El Computer -> Formula ;

  -- (hostStatus ?Computer ?Status) means that ?Status 
  -- describes the status of the Computer, such as HostDown, HostReady.
  fun hostStatus : El Computer -> El ComputerStatus -> Formula ;

  -- The degree of sharpness of a displayed or printed image.
  fun imageResolution : El ImageFile -> El PhysicalQuantity -> Formula ;

  -- (ipAddressOf ?HOST ?ADDRESS) holds if ?ADDRESS is the IPAddress of 
  -- the computer ?HOST.
  fun ipAddressOf : El Computer -> El IPAddress -> Formula ;

  -- In performance measurement, the current use of a 
  -- system as a percentage of total capacity.
  fun load : El ComputerComponent -> El ConstantQuantity -> Formula ;

  -- (maximumReplications ?PROGRAM ?INTEGER) means that 
  -- ?INTEGER represents the maximum number of copies of this application which can be run 
  -- during a process.
  fun maximumReplications : El ComputerProgram -> El PositiveInteger -> Formula ;

  -- (memorySize ?System ?Size) holds if 
  -- ?Size is the required memory size for the ComputationalSystem ?System.
  fun memorySize : El ComputationalSystem -> El ConstantQuantity -> Formula ;

  -- (minimumReplications ?PROGRAM ?INTEGER) means that ?INTEGER represents 
  -- the minimum copies of the application ?PROGRAM required to be survivable, where a program is 
  -- survivable if the failure of one or more resources does not result 
  -- in the failure of the program. Either long MTTF for the system as a 
  -- whole or short MTTR when failure occurs would improve the survivability
  -- of a program.
  fun minimumReplications : El ComputerProgram -> El PositiveInteger -> Formula ;

  -- (monitorApplicationData ?TIME 
  -- ?APPLICATION) holds if the time stamp ?TIME specifies the time at which 
  -- ?APPLICATION is running.
  fun monitorApplicationData : El TimePosition -> El ComputerProgram -> Formula ;

  -- (monitorComponentData ?TIME ?ID 
  -- ?NUMBER) holds if at time ?TIME, a component with the IDNumber ?ID 
  -- has a performance of a value ?NUMBER.
  fun monitorComponentData : El TimePosition -> El SymbolicString -> El RealNumber -> Formula ;

  -- (monitorConnectivityData ?TIME 
  -- ?IPADDRESS) is a relation between a timestamp ?TIME and an ?IP address.
  fun monitorConnectivityData : El TimePosition -> El IPAddress -> Formula ;

  -- (numberOfCPUs ?COMPUTER ?INTEGER) means 
  -- that the number of CPUs for the host ?COMPUTER is equal to INTEGER.
  fun numberOfCPUs : El Computer -> El PositiveInteger -> Formula ;

  -- (password ?Password ?User) means that ?Password is 
  -- the password the ComputerUser uses while logging onto a computer system.
  fun password : El ComputerUser -> El ComputerPassword -> Formula ;

  -- (performanceResult ?EVENT ?COMPONENT ?NUMBER) holds if the performance of
  -- ?COMPONENT has a value ?NUMBER, measured by ?EVENT, an instance of MeasuringPerformance.
  fun performanceResult : El MeasuringPerformance -> El ComputerComponent -> El RealNumber -> Formula ;

  -- (portNumber ?PROGRAM ?NUMBER) holds if ?NUMBER identifies a protocol 
  -- port, i.e. a TCP_IP software abstraction used to distinguish different applications providing 
  -- services within a single destination computer. The different ports on a host are identified by a 
  -- positive 16_bit number.
  fun portNumber : El ComputerProgram -> El PositiveInteger -> Formula ;

  -- (priority ?SYSTEM ?QUANTITY) means that the 
  -- priority of the ?SYSTEM is characterized by a PriorityAttribute, such 
  -- as HighPriority or LowPriority.
  fun priority : El ComputationalSystem -> El PriorityAttribute -> Formula ;

  -- (processAborted ?Abort ?Process) means 
  -- that the ComputerProcess ?Process is aborted as the result of ?Abort.
  fun processAborted : El Abort -> El ComputerProcess -> Formula ;

  -- (processID ?PROCESS ?NUMBER) holds if ?NUMBER is a unique number 
  -- generated by the operating system and used to refer to the ComputerProcess ?PROCESS. There 
  -- is usually no significance to the numbers as they are reused as old processes die and new processes 
  -- are created.
  fun processID : El ComputerProcess -> El PositiveInteger -> Formula ;

  -- The arguments of this relation are data 
  -- structures, each of which contains the information necessary for the 
  -- process already loaded by the operating system to execute on a processor.
  fun processList : [El Entity] -> Formula ;

  -- (productModel ?Model ?Product) means that 
  -- ?Model represents the type of the Product ?Product
  fun productModel : El SymbolicString -> El Product -> Formula ;

  -- (programCopy ?File ?Program) means that 
  -- the ComputerFile ?File is one of the copies of the ComputerProgram 
  -- ?Program.
  fun programCopy : El ComputerFile -> El ComputerProgram -> Formula ;

  -- (programRunning ?Process ?Program) 
  -- means that the ComputerProcess ?Process is executing the 
  -- ComputerProgram ?Program.
  fun programRunning : El ComputerProcess -> El ComputerProgram -> Formula ;

  -- (qoSSlack ?PATH ?MIN ?MAX) holds if ?PATH 
  -- has a realtime QoS maximum slack percentage of ?MAX and minimum of ?MIN.
  fun qoSSlack : El ComputerPath -> El ConstantQuantity -> El ConstantQuantity -> Formula ;

  -- (rMProgram_of ?RM ?SYSTEM) means that 
  -- ?RM is the resource management program of the SoftwareSystem ?SYSTEM.
  fun rMProgram_of : El ResourceManagementProgram -> El SoftwareSystem -> Formula ;

  -- (requestRate ?Request ?Period) means that 
  -- ?Period is the period at which the user sends its ?Request.
  fun requestRate : El UserRequest -> El TimeDuration -> Formula ;

  -- (resourceUsed ?Process ?Resource) means that the 
  -- ComputerProcess ?Process has access to the ComputerResource ?Resource.
  fun resourceUsed : El ComputerProcess -> El ComputerResource -> Formula ;

  -- (responseRate ?Response ?Period) means 
  -- that ?Period is the period at which the computer sends its ?Response.
  fun responseRate : El ComputerResponse -> El TimeDuration -> Formula ;

  -- The time it takes for the computer to comply 
  -- with a user's request, such as looking up a customer record.
  fun responseTime : El UserRequest -> El TimeDuration -> Formula ;

  -- (runningOn ?Program ?Computer) holds if the 
  -- ComputerProgram ?Program is being executed on ?Computer.
  fun runningOn : El ComputerProgram -> El Computer -> Formula ;

  -- (runsOn ?Program ?Computer) means that ?Program 
  -- is capable of running on ?Computer.
  fun runsOn : El ComputerProgram -> El Computer -> Formula ;

  -- (sendRate ?Program ?Period) holds if ?Period is the 
  -- period at which the ComputationalSystem ?System sends data reports.
  fun sendRate : El ComputationalSystem -> El TimeDuration -> Formula ;

  -- (settlingTime ?PROGRAM ?TIME) says that ?TIME represents seconds to delay
  -- after an action was taken with respect to QoS.
  fun settlingTime : El ComputerProgram -> El TimeDuration -> Formula ;

  -- (shutdownOf ?SHUTDOWN ?PROGRAM) holds just 
  -- in case an instance of ShutdownBlock ?SHUTDOWN specifies a set of 
  -- instructions to end ?PROGRAM.
  fun shutdownOf : El ShutdownBlock -> El ComputerProgram -> Formula ;

  -- (simpleDeadline ?PATH ?TIME)holds if 
  -- ?TIME is the maximum end_to_end path latency during a cycle of a 
  -- continuous or quasicontinuous path or during the activation of a transient 
  -- path.
  fun simpleDeadline : El ComputerPath -> El TimeDuration -> Formula ;

  -- (slidingWindowSize ?PATH ?N) holds 
  -- if PATH has a realtime QoS sliding window size of ?N measured samples.
  fun slidingWindowSize : El ComputerPath -> El PositiveInteger -> Formula ;

  -- (softwarePath ?SYSTEM ?PATH) means that 
  -- ?PATH is a computer path for the instance of SoftwareSystem ?SYSTEM.
  fun softwarePath : El SoftwareSystem -> El ComputerPath -> Formula ;

  -- (standardErrorDevice ?PROGRAM ?DEVICE) holds just in case the DEVICE is the predefined 
  -- error channel with which the running version of this program is initialised.
  fun standardErrorDevice : El ComputerProcess -> El ComputerOutputDevice -> Formula ;

  -- (standardInputDevice ?PROCESS ?DEVICE) holds just in case the DEVICE is 
  -- the predefined input channel with which the running version of the program PROCESS is initialised.
  fun standardInputDevice : El ComputerProcess -> El ComputerInputDevice -> Formula ;

  -- (standardOutputDevice ?PROGRAM ?DEVICE) holds just in case the DEVICE is 
  -- the predefined output channel with which the running version of this program is initialised.
  fun standardOutputDevice : El ComputerProcess -> El ComputerOutputDevice -> Formula ;

  -- (startupOf ?STARTUP ?PROGRAM) holds just in case an instance of
  -- StartupBlock ?STARTUP specifies a set of instructions to start the ?PROGRAM.
  fun startupOf : El StartupBlock -> El ComputerProgram -> Formula ;

  -- (startupTimeDelay ?PROGRAM ?TIME) 
  -- says that ?TIME is the time to delay after the previous application 
  -- was started before starting the application ?PROGRAM.
  fun startupTimeDelay : El ComputerProgram -> El TimeDuration -> Formula ;

  -- (stateOfProcess ?PROCESS ?STATE) says 
  -- that ?STATE is a state of the ComputerProcess ?PROCESS.
  fun stateOfProcess : El ComputerProcess -> El ProcessState -> Formula ;

  -- (status ?PROCESS ?STATUS) holds if ?STATUS is the current status of ?PROCESS.
  fun status : El ComputerProcess -> El ProcessStatus -> Formula ;

  -- (strictness ?System ?Attribute) holds if 
  -- the StrictnessAttribute ?Attribute describes the RealtimeSystem ?System.
  fun strictness : El RealtimeSystem -> El StrictnessAttribute -> Formula ;

  -- (systemBehavior ?System ?Attribute) 
  -- holds if ?Attribute is a SystemBehaviorAttribute which describes the 
  -- RealtimeSystem ?System.
  fun systemBehavior : El RealtimeSystem -> El SystemBehaviorAttribute -> Formula ;

  -- (systemMeasured ?Event ?System) means that ?Event is an event of measuring
  -- the performance of the ComputationalSystem ?System.
  fun systemMeasured : El MeasuringPerformance -> El ComputationalSystem -> Formula ;

  -- (task ?Process ?Task) means that ?Task is a function to 
  -- be performed by the ComputerProcess ?Process.
  fun task : El ComputerProcess -> El ProcessTask -> Formula ;

  -- (taskRelation ?System ?Attribute) holds 
  -- if ?Attribute is a TaskRelationAttribute which describes the 
  -- RealtimeSystem ?System.
  fun taskRelation : El RealtimeSystem -> El TaskRelationAttribute -> Formula ;

  fun thresholdOf : El Computer -> El PositiveRealNumber -> Formula ;

  -- (unitMeasuringPerformance ?COMPONENT ?UNIT) holds in case ?UNIT is 
  -- an instance of UnitOfMeasure which is used to measure the performance of ?COMPONENT.
  fun unitMeasuringPerformance : El ComputerComponent -> El UnitOfMeasure -> Formula ;

  -- (userName ?Name ?User) means that ?Name is the name the ComputerUser uses 
  -- to identify himself or herself when logging onto a computer system.
  fun userName : El ComputerUser -> El UserName -> Formula ;

}