José Reinaldo Silva

itSIMPLE: towards an integrated design system for real planning applications

Since the end of the 1990s there has been an increasing interest in the application of AI planning techniques to solve real-life problems. In addition to characteristics of academic problems, such as the need to reason about actions, real-life problems require detailed knowledge elicitation, engineering, and management. A systematic design process in which Knowledge and Requirements Engineering tools play a fundamental role is necessary in such applications. One of the main challenges in such design process, and consequently in the study of Knowledge Engineering in AI planning, has been the analysis of requirements and their subsequent transformation into an input-ready model for planners. itSIMPLE is a research project dedicated to the study of a project process to support the design phases of reallife planning models. In this paper, we give an overview of itSIMPLE focusing on the main translation processes among a minimal set of representations: from requirements represented in UML to Petri Nets and from UML models to PDDL for problem solving.

New Trends in Manufacturing: Converging to Service and Intelligent Systems

Abstract Manufacturing processes and models have been influenced by the linear approach, called Fordism, for almost a century, since the first automated devices and discrete control systems were introduced. At the same time, new ideas to organize manufacturing process have appeared that question the absolute dominance of gain in scale. More recently, new criteria invaded the scenario of manufacturing where quality led manufacturing process to a phase based on accurate supply chain and surrounded by ubiquitous computer and robotic devices. A very precise manufacturing processes can now be designed and implemented in almost all sectors of industry, where special sub-processes can be delivered by other players. In this new scenario, a new paradigm for manufacturing design emerged, based on a set of very specialized services that could be arranged to provide new creative and sustainable processes. In this paper we go into this new paradigm for manufacturing (process) design comparing it with the classic approach that relies on layers classified as production plant, control (software oriented) and supervisory.

Applying Petri Nets to Requirements Validation

Abstract Mechatronics and Information Systems can be assumed as complex, and thus have a prohibitive cost for adjustments out of the specification phase. This emphasizes the early development phases as especially critical for the success of projects, besides being very important to guide implementation decisions. We proposed a requirement validation method suitable to a life cycle represented with the Unified Process and addressed to the specification and design of information systems. The key issue of the proposal is the facility to model information flow formally, by the capture of the requirements into Elementary Petri Nets. A software tool is proposed to perform the transformation capturing the dynamic of the processes. Requirements validation is performed in the net, by simulation or by property analysis (suitable to large systems). Finally, we briefly discuss the achievement of a proper (and minimum) set of viewpoints enrolled in information system projects.

Modeling of Programs and Its Verification for Programmable Logic Controllers

Abstract Programmable logic controller is still the main device used for control of productive systems, which can be approached as discrete event dynamic systems. For programming these controllers, five languages were standardized by IEC 61131, and the LD (ladder diagram) language is distinguished among the others, i.e., it has been widely applied in productive systems, even with studies that confirm the restrictions and problems regarding the use of this language, such as the difficulties for errors identification in developed control programs. Therefore, this work presents a proposal for the modeling of extended finite state machines from control programs written in LD. These models are verified through a computational tool, aiming the identification of possible errors in the control program.

Timed Petri Nets

In the early 60’s a young researcher in Darmstadt looked for a good representation for communicating systems processes that were mathematically sound and had, at the same time, a visual intuitive flavor. This event marked the beginning of a schematic approach that become very important to the modeling of distributed systems in several and distinct areas of knowledge, from Engineering to biologic systems. Carl Adam Petri presented in 1962 his PHD which included the first definition of what is called today a Petri Net. Since its creation Petri Nets evolved from a sound representation to discrete dynamic systems into a general schemata, capable to represent knowledge about processes and (discrete and distributed) systems according to their internal relations and not to their work domain. Among other advantages, that feature opens the possibility to reuse some experiences acquired in the design of known and well tested systems while treating new challenges.

Are Automated Planners up to Solve Real Problems

Abstract It is a well known fact that the AI planning community is very committed to apply the developments already achieved in this area to real complex applications. However realistic planning problems bring great challenges not only for the designers during design processes but also for the automated planners during the planning process itself. In addition, it is quite common to face issues about whether the available planners will be up to solve the problem being modeled during the initial design stages. In this paper we present the experience, results and issues that emerged from testing the performance of the recent planners when solving a real and complex problem such as the planning of daily activities of a petroleum plant for docking, storing and distributing oil. Due to the complexity of this real planning problem, the KE tool itSIMPLE was used in order to support all the design processes such as specification, modeling and domain model analysis that resulted in a PDDL model, automatically generated by the tool, which was used as input for planners. In addition, we present the main modeling process performed for the domain model construction.

Scientific Collaboration and Knowledge Sharing in the Virtual Manufacturing Network

Abstract Most of past research efforts on Collaborative Work Support adopt tool-centric approaches to define cooperation. These approaches are often related to a single category of communication (synchronous or asynchronous) and support only a single type of collaboration (planned or open). In this paper, vc describe our view for successful collaboration in Virtual Manet. Our aim is to extend the classical asynchronous computer-supported scientific collaboration by introducing and integrating collaborative work support tools with knowledge management approaches. We are starting by effective requirements analysis, and we will continue by identifying the associated collaboration technologies, and finally defining the Cooperative e-Space integration architecture. The idea can be generalized to encompass the manufacturing business or the collaborative production in virtual enterprises.

A service-oriented framework to the design of information system service

The beginning of this century is marked by a paradigm shift due to the move of the production focus from goods-dominant to a service-dominant. At the same time, manufacturing automation and integration are undergoing changes, which open the possibility for classical model oriented products to be replaced by service models, supported by cognitive information systems. This paper analyzes a proposal to achieve a sound design process for service systems, which follows the model driven tendency. In fact, the aim is to bring together practical and formal approach, and therefore, to propose a good design discipline based on SOMF (Service Oriented Model Framework). Based on this model driven approach a new environment were developed which supports elicitation, modeling and requirements analysis supported by semi-formal methods (SOMF and UML) and formal methods (by using SysML and Petri Nets). The proposed method is applied to a case study based in an urban Smart Grid.

Interactive design of integrated systems

The design of autonomous integrated discrete systems requires the anticipation of behaviour and co-operative actions among subsystems. Promising and already successful approaches to this kind of system always rely in sound formal methods, which can be applied once a conceptual design is provided. However, there is a gap between the achievement of a conceptual model and the remaining process, in part because integration and flexibility are currently used as vague concepts, and also because organisation aspects in conceptual design appear only informally.

PFS/MFG: A High Level Net for the Modeling of Discrete Manufacturing Systems*

A formalism for an extended Condition/Event Petri Net, PFS/MFG (Production Flow Schema/Mark Flow Graph) is introduced in this work. The algebraic relations provided can be used in behavior and structural property analysis of discrete systems modeled in this technique. Behavior analysis is based on a simulator which specifications and some algorithms are presented here. The resulting net can be applied to the design, modeling and evaluation of configurations in Factory Automation as well as to discrete shop floor control. Briefly, we describe a realistic application of the revised PFS/MFG net in a medium size printers factory.