1. A Blackboard Globally Recast as an Interpreter - Jairam Kamath www.bookspar.com | Website for Students | VTU NOTES | QUESTION PAPERS | NEWS | RESULTS 1

2. A Blackboard Globally Recast as an Interpreter The blackboard model of problem solving is a highly structured special case of opportunistic problem solving. The solution space is organized into several application- dependent hierarchies and the domain knowledge partitioned into independent modules of knowledge that operate on knowledge within and between levels. www.bookspar.com | Website for Students | VTU NOTES | QUESTION PAPERS | NEWS | RESULTS 2

3. Basic architecture of a blackboard system Three Major parts: Knowledge sources The blackboard data structure Control Example: HEASRSAY – II www.bookspar.com | Website for Students | VTU NOTES | QUESTION PAPERS | NEWS | RESULTS 3

4. 4 ----> Control flow ____ Data flow

5. www.bookspar.com | Website for Students | VTU NOTES | QUESTION PAPERS | NEWS | RESULTS 5 ----> Control flow ____ Data flow

6. -Blackboard HEARSAY-II speech recognition system. The blackboard structure is a six- to eight-level hierarchy in which each level abstracts information on its adjacent lower level. blackboard elements represent hypotheses about the interpretation of an utterance. www.bookspar.com | Website for Students | VTU NOTES | QUESTION PAPERS | NEWS | RESULTS 6

7. -Knowledge Sources Knowledge sources correspond to such tasks as segmenting the raw signal, identifying phonemes, generating word candidates, hypothesizing syntactic segments, and proposing semantic interpretations. Each knowledge source is organized as a condition part that specifies when it is applicable and an action part that processes relevant blackboard elements and generates new ones. www.bookspar.com | Website for Students | VTU NOTES | QUESTION PAPERS | NEWS | RESULTS 7

8. -Control The control component is realized as a blackboard monitor and a scheduler. The scheduler monitors the blackboard and calculates priorities for applying the knowledge sources to various elements on the blackboard. www.bookspar.com | Website for Students | VTU NOTES | QUESTION PAPERS | NEWS | RESULTS 8

9. 9 ----> Control flow ____ Data flow

10. Interpreter View The complexity arises because it is now illustrating two concepts: The blackboard model and realization of that model by a virtual machine. The blackboard model can be recovered by suppressing the control mechanism and regrouping the conditions and actions into knowledge sources. www.bookspar.com | Website for Students | VTU NOTES | QUESTION PAPERS | NEWS | RESULTS 10

11. Interpreter View The interpretation engine includes several components like: the blackboard monitor, the focus of control database, and the scheduler, but also the actions of the knowledge sources. The scheduling queue corresponds roughly to the control state. www.bookspar.com | Website for Students | VTU NOTES | QUESTION PAPERS | NEWS | RESULTS 11

12. Conclusion We see a system initially designed with one model (blackboard, a special form of repository), then realized through a different model (interpreter). The view as an interpreter is a different aggregation of components from the view as blackboard. www.bookspar.com | Website for Students | VTU NOTES | QUESTION PAPERS | NEWS | RESULTS 12

13. www.bookspar.com | Website for Students | VTU NOTES | QUESTION PAPERS | NEWS | RESULTS 13

14. Thank You www.bookspar.com | Website for Students | VTU NOTES | QUESTION PAPERS | NEWS | RESULTS 14