330 likes | 513 Views
Task 2.1 : KBS architecture development and platform implementation. Methodology for KBS development. It comprises 5 phases, each one characterized by precise goals to be achieved and clear relationships with the other phases.
E N D
Task 2.1 : KBS architecture development and platform implementation INTB
Methodology for KBS development • It comprises 5 phases, each one characterized by precise goals to be achieved and clear relationships with the other phases. • Each phase is subdivided into a number of specific tasks, each one devoted to achieve a precise subgoal. • Tasks can be performed by executing specific activities, which define at grater level of detail what to do and how. • The five phase are: • Phase 1 – Plausibility study • Phase 2 – Construction of the demonstrator • Phase 3 – Development of the prototype • Phase 4 – Implementation and installation of the target system • Phase 5 – Maintenance INTB
Plausibility study plausibility study report demonstrator Construction of the demonstrator demonstrator report prototype Development of the prototype development support system prototype report target system Implementation and installation of the target system maintenance support system target system report Maintenance possibleinterventions Phases and main products INTB
Phase 1: Plausibility study The plausibility study encompasses the following main goals: • analyzing the application domain (material design and production process design); • analyzing the requirements and the project goals; • identifying the main functional, operational, and technical specifications of the KBS, and the acceptance criteria; • developing a draft architectural design and a draft external (DoD/FEA) connections design. • The product of the plausibility study is the • plausibility study report. • It is a technical document which illustrates the activities done and the results obtained. INTB
Phase 1: Plausibility study The concept of plausibility includes the following aspects: • technical feasibility of the KBS application based on domain characteristics; • state of the art of the available technologies; • introduction of the KBS in its operational place and environment; • economic suitability issues. INTB
Phase 2: Construction of the demonstrator The main goal of the construction of the demonstrator is to develop and demonstrate a first, limited version of the KBS in order to meet the following issues: • obtaining a concrete insight in the complexity of the problem considered, and validating, refining, and, if necessary, revising technical decision outlined in the plausibility report; • collecting useful feedback from the users, and refining the identification of requirements and definition of KBS specification stated in phase 1. INTB
Phase 2: Construction of the demonstrator The products of this phase are: • a running KBS functionality demonstrator, which anticipates the system performance on a limited and meaningful part of the considered problem; • the demonstrator report, which contains a synthesis of the activities carried out and a detailed illustration of the results achieved. INTB
Phase 3: Development of the prototype The main objective of this phase is to find the most suitable technical solutions for the application considered, and to implement them in a running system. The products of this phase are: • a full KBS, called prototype, which can adequately meet all functional specifications stated; • a set of software tools which supports the construction of the knowledge base of the prototype; • the prototype report, which contains a synthesis of the activities carried out and a detailed illustration of the results achieved. INTB
Phase 3: Development of the prototype The prototype, although satisfying the functional specifications stated, is not the final output of the production process, since: • it is not installed in the real operational environment, but it is running only in the development environment (if necessary, connections with DoD/FEA are simulated); • it has only been tested with sample data prepared by the system designer with the support of experts and users. INTB
Phase 4: Implementation and installation of the target system The goal of this phase is to develop a complete KBS. It must have the same behavior of the prototype, but in addition it must be: • installed in the real operational environment (VEE); • filed tested with a selection of real data; • eventually delivered to the end-users for routine operation. INTB
Phase 4: Implementation and installation of the target system The products of this phase are: • the target system, that is, the final output of the whole KBS production process; • the maintenance support system, that is the specific system devoted to support effective and efficient maintenance; • the target system report, which contains a synthesis of the activities carried out and a detailed illustration of the results achieved. INTB
Phase 5: Maintenance • This phase starts after the delivery of the target system to the user for the operational use. • In this phase the developer collects feedback from the end-users in order to schedule possible maintenance interventions. INTB
Draft of Architecture KBS Design • System Overview • Technical Details • Platform Scheme INTB
SystemOverview • Structure • Our KBS integrates the conventional KB with a OODBMS. • Motivations • Integration of KB e DBMS exploits intelligence of KB and OODBMS efficiency in management complex structured data. • K.B provides data-driven computation and expressive power in D.B interrogation • Semantic Data Model : • EER+OO The semantic data model encapsulates in Extended Relational Model the multi-level abstraction paradigm of OO INTB
TechnicalDetails • KBS-Shell • integrates Rule-based and OO programming paradigms in Java environment • DBMS • is an OODBMS with OO-query language which may interfaced with C++ and SQL • KBS/ DBMS Interface • Java/CORBA with Object Persistence • External interface • Interface with STEP/EXPRESS data format from CAD/CAE is performed by a OO-translator INTB
OPSJ-Shell OPSJ-Shell OPSJ-Shell Platform Scheme JAVA Environment CORBA- IDL STEP-file ObjectStore CAD/CAE ST-ObjectStore INTB
Sw Tools for System development • Expert System Shells • OPSJ is an OPS5 + OO which may be embedded in a Java package • OODBMS • Objectstore: is an OODBMS with a C++/Java interface • Internal Interface • Java/CORBA Development Tools • Integration CAD/CAE <-> DBMS • ST-Objectstore is an OO-translator based on ROSE class library INTB
OPSJ • Motivations: • Meets the requirement of rule-based + OO integration • Can be embedded in Java applications • Technical Features • OPSJ engine is written completely in Java • OPSJ is designed to add rules to Java • OPSJ, rules are grouped into units called "Knowledge Sources." • Forward Chaining (Inductive paradigm) • RETE-II Match Algorithm more efficient than CLIPS • OO Pattern Matching of Java/CORBA Class in LHS INTB
ObjectStore • Motivations: • is an OODBMS • Provides an Integrate Development Environment • Provides a rich set of toolbox for integration with C++/Java applications • May be easily interfaced with STEP/EXPRESS data format by the ST-Objectstore Tool. • Technical Features • Query Language • OO embedded Query Language which can be interfaced with SQL • Object Management • Persistent Object Exportable toward Java Environment (Objectstore PE) INTB
ST-Objectstore • Motivations • Make easy the interfacing with CAD/CAE Systems,allowing Import/Export of STEP files from OODBMS • Technical features • ST-Objectstore is a special ROSE class library • ST-Objectstore uses C++ class • ST-Objectstore provides Object Persistence INTB
Knowledge Base Knowledge Based System: the Demonstratortask 2.1 INTB
Motivations and goals • Develop a running system: • anticipate a sub-set of the functions; • draft architectural design; • domain experts and users concretely involved and committed. • Two main goals: • developing a better understanding of user requirements; • identifying more detailed and precise specifications of the KBS. INTB
KBS Component KB Exclusion Component type DB Materials & Processes Selection Selection criteria Material design Thickness Computation Verification FEM Processes Process tool Computation Verification Geometry Constraints Computation Verification INTB
Openness and separation of concerns • Openness. May vary: • the number of clusters and modules; • the relation between them; • the external connections, without changing the structure of the system. • Separation of concerns: • every cluster and module has its own task, • the modifications of the behaviour of one of them do not affect the behaviour of the others. INTB
Computation/Verification modules KBS KB Input Historical data (domain specific) Action Computation Materials Processes Constraints ... Verification Output External tools INTB
Example: the blade Component blade Exclusion Component type water INTB
DB Chemical Mechanical Fiber % Thickness Cost ……. Exclusion Exclusion Eliminates all materials that do not respond to the characteristics required by the specific component and by its type. INTB
Selection • After the exclusion, a subset of materials remains. • The demonstrator shows the list of the candidate materials, among which the user can choose one or more. • The present demonstrator lets the user choose only one. Selection Selection criteria Epoxy-Kevlar INTB
DB Chemical Mechanical Fiber % Thickness Cost ……. Composite design Thickness Material design 12 mm Computation Verification • The thickness of the component when made of traditional material; this information can be retrieved from an external DB. • Retrieving characteristics from the KBS database for the preparation of the first design of the composite. INTB
FEM Verification of the composite Material design Computation Verification • Connection with a external tool, testing the composite properties. • The control can loop to the previous cluster to compute another candidate solution or discard the material. INTB
Process tools Process tool Processes Processes Yes Computation Verification • The system indicates the best available process tool. • Actually, the demonstrator considers only one possible process that can modify the laminate. INTB
Geometry Geometry Constraints Computation Verification • This is just a verifying module. • The demonstrator verifies whether the thickness of the laminate is within a given range. INTB
Output KBS Composite specifications • The thickness of the laminate • The composite material • The number of plies • The sequence model • An indication of the final cost. DoD INTB