Abstract: A method for determining a target path for a model-based control system. The model-based control system includes a directed acyclic graph, where the directed acyclic graph includes a plurality of vertices interconnected by a plurality of edges. The method includes the steps of performing a depth-first search of the directed acyclic graph for the target path. The depth-first search is operative to return an explicit solution or an implicit solution, wherein the implicit solution is determined using a heuristic. The method further includes determining if the depth-first search returned an explicit solution or an implicit solution, and if the depth-first search returned an implicit solution, constructing the target path from the implicit solution. The method may further include constructing a pattern database.

Abstract: A method and computer product is provided to generate a signal model for use in analyzing a model system including imposing an explicit time assumption for each time instant of the system model. The time assumptions are defined so that any two assumptions contradict each other, thereby separating all inferences into the respective times. A non-monotonic rule is applied to instantiate component models of the model system. Results are defined as not depending on the existence of a previous time instant and, a simplified signal model is generated, wherein the signal model represents the evolution of a value in the model system over time.

Abstract: A computer-based method and system for pervasive model adaptation are provided. The method includes providing a production plan to a production system, executing the production plan in the production system, collecting observation data produced by at least one sensor in the production system during execution of the production plan into computer memory, calculating changes to be made to a system model in the computer memory based on the collected observation data, dynamically updating the system model according to the calculated changes, creating an updated production plan based at least partially on the dynamically updated system model, and storing the updated production plan within the computer memory.

Abstract: Target value search methods and systems are presented for solving a target value path problem to identify a path or paths in a graph in which a connection graph is created and upper and lower bound values are determined for each node in the connection graph, and a first best search is performed to identify a path or paths from a starting node to a goal node having a path value closest to the target value.

Abstract: Systems and methods are presented for constructing production plans to achieve one or more production goals, in which a diagnosis engine determines the production plant condition based on a previously executed plan, observations from the plant, and a plant model, and formulates a heuristic based on a diagnostic objective, and with a planner to performing a partial-plan search using the heuristic to construct the plans that will concurrently achieve at least one production goal and facilitate the diagnostic objective.

Abstract: Production control systems and methods are presented for estimation of production resource failure probabilities in which a set of four count values are maintained and updated for each resource including a first count value m11 indicating a number of plans where the resource m was used and failed, a second count value m10 indicating a number of plans where the resource m was used and succeeded, a third count value m01 indicating a number of plans where the resource m was not used and failed, and a fourth count value m00 indicating a number of plans where the resource m was not used and succeeded, and the current fault probability for each resource is estimated and stored for single or multiple, persistent or intermittent faults based on the corresponding count values.

Abstract: A control systems and methods are presented for controlling a production system, in which a model-based planner includes a formulation, such as a SAT formulation representing possible actions in the production, with a solver being used to provide a solution to the formulation based at least partially on production and diagnostic goals and the current plant condition, and a translation component translates the solution into a plan for execution in the plant.

Abstract: A modeled-based reasoning system and method including dynamic domain abstraction, includes the use of an abstraction determining module configured to identify an appropriate abstraction level for a system model of a real-world system to be analyzed, from a plurality of potential abstraction levels. A system reasoning module is configured to perform analysis on the system model of the real-world system at the abstraction level determined to be appropriate by the abstraction determining module.

Abstract: A method and system for diagnosing any combination of persistent and intermittent faults. The behavior of a system under test is obtained by measuring or probing the system at a particular location(s). The predicted behavior of a modeled system corresponding to the system under test is investigated by drawing inferences based on at least conditional probabilities, prior observations and component models. The predictions are compared to their corresponding points in the system under test. A determination is made if a conflict exists between the measured behavior and the predicted behavior, and the conditional probabilities are adjusted to more and more accurately reflect the action fault(s) in the system under test. The conflicts or deviations between the obtained predicted behavior and the actual behavior are used to isolate the components of the system causing the faults.

Abstract: A system and method provides decision support for planning in an environment where a competition for use of resources exist and events affecting the planning are occurring dynamically. A system model of an actual system is provided. Then in a dynamic factored manner, an envisionment related to at least some aspects of the system model is built. From this envisionment output is generated related to at least some aspects of the system model. Finally, changes are made to the actual system, based on the generated output thereby changing a configuration and/or operation of the actual system.

Abstract: A method and computer program product models connections for a system having a plurality of components, having component terminals, and connections. The connections are located to selectively connect the components of the system to each other. The method and computer product models signal levels for nodes of the system as a variable wherein the nodes of the system are representative of the connections. Each potential component terminal connection of the connections that could potentially influence the signal level on each of the nodes is modeled, as a qualitative variable. This results in each node of the system being modeled with n+1 variables.

Abstract: Model-based production control systems and methods are presented for constructing plans for controlling operation of a production system with a plant having a plurality of resources to achieve one or more production goals, in which a planner constructs plans for execution in the plant based on production goals while balancing both production objectives (e.g., production cost, production time) and diagnostic objectives (e.g., diagnostic cost, information gained, repair cost), and a diagnosis engine determines a current plant condition based on a previously executed plan and corresponding observations from the plant, and provides expected information gain data to the planner, with the planner generating a plan that will achieve a given production goal and is improved for one or more diagnostic objectives and the expected information gain data.

Abstract: A computer-based method and system for pervasive model adaptation are provided. The method includes providing a production plan to a production system, executing the production plan in the production system, collecting observation data produced by at least one sensor in the production system during execution of the production plan into computer memory, calculating changes to be made to a system model in the computer memory based on the collected observation data, dynamically updating the system model according to the calculated changes, creating an updated production plan based at least partially on the dynamically updated system model, and storing the updated production plan within the computer memory.

Abstract: Methods and systems for solving a target value search problem using a multi-interval heuristic are presented. The methods and system identity a path, or paths, in a graph, whereby a connection graph is created and range sets are generated for each vertex in the connection graph. Range sets include one or more intervals. Thereafter, a best search is performed to identify a path, or paths, from a starting vertex to a goal vertex having a path value closest to a target value.

Abstract: A method for determining a target path for a model-based control system. The model-based control system includes a directed acyclic graph, where the directed acyclic graph includes a plurality of vertices interconnected by a plurality of edges. The method includes the steps of performing a depth-first search of the directed acyclic graph for the target path. The depth-first search is operative to return an explicit solution or an implicit solution, wherein the implicit solution is determined using a heuristic. The method further includes determining if the depth-first search returned an explicit solution or an implicit solution, and if the depth-first search returned an implicit solution, constructing the target path from the implicit solution. The method may further include constructing a pattern database.

Abstract: This NGDE algorithm incorporates a minimum cardinality candidate diagnosis generator which exploits conflict set reduction rules to dramatically reduce the search space and thus reduce the computational resources required to find minimum cardinality diagnoses.

Abstract: A computer based method and system for tiered inference multiple fault diagnosis is provided. The method includes using a computer processor to dissect a hypothesis space representing a production system having a plurality of production modules into tiers. Production modules in the current tier are partitioned into a group or a set of sub-groups. A fault diagnosis algorithm is applied to the group of each sub-group to identify an acceptable fault diagnosis. When no acceptable fault diagnosis is found, the process moves to the next tier to perform further investigations. The process continues to move to higher tiers until an acceptable fault diagnosis is obtained or the system instructs the process to end.

Abstract: Diagnostic systems and methods are presented for determining the current condition of a production plant and the resources thereof, in which successively more complex diagnostic abstractions are used to determine the plant condition, with a more complex abstraction being selected when the most recently selected diagnostic abstraction is logically inconsistent with the current fault status indications.

Abstract: A method and apparatus for maintaining groupings and relationships of propositions associated with a knowledge base is provided. In one embodiment, the method includes: a) providing multiple microtheories to form a knowledge base, each microtheory comprising multiple propositions, b) providing an mt label for each microtheory, c) providing a proposition label for each proposition, d) comparing the proposition label for a specific proposition with the microtheory labels in response to a transaction request, and e) determining which microtheory labels have a common element with the proposition label. In another embodiment, the method may include a) providing multiple microtheories, b) providing an mt label for each microtheory, and c) initializing tags for first and second microtheories to a clean value. In one embodiment, the apparatus may include one or more storage devices and a tag processing logic.

Abstract: Systems and methods are presented for constructing production plans to achieve one or more production goals, in which a diagnosis engine determines the production plant condition based on a previously executed plan, observations from the plant, and a plant model, and formulates a heuristic based on a diagnostic objective, and with a planner to performing a partial-plan search using the heuristic to construct the plans that will concurrently achieve at least one production goal and facilitate the diagnostic objective.