sa unit-2-three-vignets
TRANSCRIPT
Three Vignettes in mixed style
Distributed process control
Dr Reeja S RProfessorCSE Dept.SJEC, Vamanjoor, Mangalore
3-Vignettes
• Plan management system– Process control with plant management.
• Information system– Five level layered hierarchy.– 1: process measurement and control– 2:process supervision for monitoring and controlling– 3:Process management- computer based plant automation-
reports, optimization guidance.– 4,5: Plant and corporate management-cost accounting, inventory
control, order processing , scheduling..
Three vignettes in mixed styleThree vignettes in mixed style
• In the above model– Layers 1-3 are object oriented– Layers 4-5 are conventional data repository
model.
Operating parameters: Current process value, target value, output and mode-automatic or manualTuning parameters: gain, reset, derivative, alarm trip-pointsConfiguration parameters: tag-name and I/O Channels
Operating parameters: Current process value, target value, output and mode-automatic or manualTuning parameters: gain, reset, derivative, alarm trip-pointsConfiguration parameters: tag-name and I/O Channels
TemplatesAlgorithmsCommunication services
• Layer 4 and 5: integrates conventional host computer and conventional database management.
• Data collection facilities of level 3 and reporting facilities of level 2 provide process information as transactions processing functions –supports central data store.
Rule based systemRule based system
Rule based system• Pseudocode: code to be executed- knowledge base.• Interpretation engine: Rule interpreter• Control state of the interpretation engine: rule and data
element• Current state of the program Working memory.
IT CALLS SET OF RULES WHOSE CONTROL RELATIONS ARE DETERMINED DURING EXECUTION BY THE STATE OF THE COMPUTATIONIt provides a virtual machine to support this model.
A blackboard globally recast as an interpreterA blackboard globally recast as an interpreter
Black board• Solution is organized into application
dependent hierarchies • Domain knowledge is partitioned into
independent modules of knowledge that operate on knowledge within levels