Validating specifications of dynamic systems using automated reasoning techniques

In this paper, we propose a new approach to validating formal specifications of observable behavior of discrete dynamic systems. By observable behavior we mean system behavior as observed by users or other systems in the environment of the system. Validation of a formal specification of an informal domain tries to answer the question whether the specification actually describes the intended domain. This differs from the verification problem, which deals with the correspondence between formal objects, e.g. between a formal specification of a system and an implementation of it. We consider formal specifications of object-oriented dynamic systems that are subject to static and dynamic integrity constraints. To validate that such a specification expresses the intended behavior, we propose to use a tool that can answer reachability queries. In a reachability query we ask whether the system can evolve from one state into another without violating the integrity constraints. If the query is answered positively, the system should exhibit an example path between the states; if the answer is negative, the system should explain why this is so. An example path produced by the tool can be used to produce scenarios for presentations of system behavior, but can also be used as a basis for acceptance testing. In this paper, we discuss the use of planning and theoremproving techniques to answer such queries, and illustrate the use of reachability queries in the context of information system development

Plan modifications versus plan generation : a complexity-theoretic perspective

The ability of a planner to modify a plan is considered as a valuable tool for improving efficiency of planning by avoiding the repetition of the same planning effort. From a computational complexity point of view, however, it is by no means obvious that modifying a plan is computationally as easy as planning from scratch if the modification has to follow the principle of "conservatism", i.e., to reuse as much of the old plan as possible. Indeed, considering propositional STRIPS planning, it turns out that conservative plan modification is as hard as planning and can sometimes be harder than plan generation. Furthermore, this holds even if we consider modification problems where the old and the new goal specification are similar. We put these results into perspective and discuss the relationship to existing plan modification systems. Although sometimes claimed otherwise, these systems do not address the modification problem, but use a non-conservative form of plan modification as a heuristic technique

SAP- Modular Tool for Specification and Analysis of User Preferences in Multiple-Criteria Model Analysis

Model based Decision Support Systems (DSS) often use multiple-criteria optimization for selecting Pareto-efficient solutions. Such a selection is based on interactive specification of user preferences. This can be done by specification of aspiration and reservation levels for criteria. Diverse graphical user interface could be used for specification of these levels as well as for interpretation of results. In the approach presented in this paper the specified aspiration and reservation levels are used for generation of component achievement functions for corresponding criteria. Such functions can be interpreted as fuzzy membership functions or as functions, which reflect the degree of satisfaction with given values of criteria. The paper outlines the methodological background and modular structure of a DSS shell for multiple-criteria analysis of decision problems that can be represented as Linear Programming (LP) or Mixed Integer Programming (MIP) problems. The DSS shell has been used at IIASA for analysis of decision problems in water quality management and land use for sustainable development planning. The pilot implementation of one component of that DSS, namely the modular software tool for interactive specification of user preferences is described in more detail. The tool has been also used as in a DSS for analysis of non-linear problems in several engineering applications

SSM Approach to Realizing Emancipatory Idels in ERP Implementation

Organizations implement Enterprise Resource Planning (ERP) systems seeking to integrate functional units, standardize business processes and enhance organizational efficiencies. Although several millions of dollars are spent in implementing ERP systems, most of these systems fail. As ERP systems are implemented in complex environments with extensive social and organizational interactions leading to dramatic changes in the organizational structures and business processes, two critical success factors in ERP implementation are user involvement and effective project communication. Although Checkland’s soft systems (SSM) methodology is a proven tool for encouraging user participation, it does not fully embrace emancipation. In this paper, we reformulate SSM to incorporate emancipatory ideals to enhance project communication during ERP implementation. The emancipatory approach developed in this paper is suitable for the requirement specification phase of ERP implementation. The approach can enhance systems implementation practice and presents an opportunity for a new research stream in method engineering for ERP systems

Preparation and control of intelligent automation systems

In the automation systems of tomorrow, it is likely that the devices included have various degrees of autonomy, and include advanced algorithms for perception and control. Human operators will be expected to work together with collaborative robots as well as with roaming robots for material handling.The volatile nature of the environment of such intelligent automation systems lead to an enormous amount of possible situations that can arise and which need to be suitably handled. This complexity makes development of control systems for intelligent automation systems difficult using traditional methods.As an alternative, this thesis presents a model-based control framework, which uses a combination of formal specification and automated planning. The proposed framework allows for defining the intentions of the automation system on a high level, which enables decisions that influence when things should occur to be modeled using logical constraints, rather than programming. To achieve a modular framework, low level, reusable, resource models are composed by 1) formal specification to ensure safety and 2) applying an abstraction called an operation, which couples the reusable resources to the intentions of the system. By planning also the resources\u27 detailed actions, the operations can, when possible, be completed regardless of the resources\u27 current state. This eases error-recovery, as resources do not have to be reset when an error occurs.Additionally, the thesis proposes an iterative and interactive workflow for integrating the proposed model-based control framework into a virtual preparation process, using computer-based simulation as a tool for validating formal specifications. The control framework allows for adding new constraints to a running system, enabling an efficient and interactive preparation process.The framework has been applied to a use case from final assembly, which features human-robot collaboration. Experimental results on the ability to handle unforeseen errors and planning performance are presented

A generic decision support tool to planning and assignment problems: Industrial application & Industry 4.0

Decision support tools are essential to help the management of industrial systems at different levels: strategic to size the system; tactical to plan activities or assign resources; operational to schedule activities. We present a generic and modular decision support tool to solve different problems of planning, assignment, scheduling or lot-sizing. Our tool uses a hybridization between a metaheuristic and a list algorithm. The specification of the considered problem is considered into the list algorithm. Several tactical and operational problems have been solved with our tool: a problem of planning activities with resources assignment for hospital systems, a lot-sizing and scheduling problem taking into account the setup time for plastic injection, and a scheduling problem with precedence constraints. At the strategic level, this tool can also be used as part of the Industry 4.0 to design reconfigurable production systems. This paper summarizes some problems solved with the proposed tool, and presents the evolution of our tool

A Generic Decision Support Tool to Planning and Assignment Problems: Industrial Applications and Industry 4.0

Decision support tools are essential to help the management of industrial systems at different levels: strategic to size the system; tactical to plan activities or assign resources; operational to schedule activities. We present a generic and modular decision support tool to solve different problems of planning, assignment, scheduling, or lot-sizing. Our tool uses a hybridization between a metaheuristic and a list algorithm. The specification of the considered problem is taken into account in the list algorithm. Several tactical and operational problems have been solved with our tool: a problem of planning activities with resources assignment for hospital systems, a lot-sizing and scheduling problem taking into account the setup time for a textile application and for a plastic injection problem, and a scheduling problem with precedence constraints. At the strategic level, this tool can also be used as part of Industry 4.0 to design reconfigurable manufacturing systems. This paper summarizes some problems solved with the proposed tool and presents its evolution

Belief systems for persuasive discourse planning

This thesis is concerned with the problem of construction of the logical structure of a persuasive discourse. A persuasive discourse can be defined as a monodirectional form of communication, generated by a speaker in order to convince a hearer about the validity (or fallacy) of a specific belief The construction of the structure of a persuasive discourse is realized, in this work, through the adoption of two basic elements: a belief system and a planning system. The planning system is used as a tool for the automatic generation of the discourse structure (or plan), obtained through the decomposition of the assigned (communicative) goals of persuasion, aimed at producing specific effects on the hearer’s beliefs. The belief system is adopted in order to endow the planning process with a formal language of beliefs for the representation of such goals, and with the mechanisms which govern the propagation of their (expected) effects on the rest of the hearer's belief state. The main results presented consist of the formalization of a paradigm for specification of belief systems, and of a method — whose correctness is formally proved — for their integration with planning systems. The formalization of a belief system for discourse structure representation (defined in accordance with the theoretical paradigm) is also given, together with the description of its implementation and integration with a specific planner, which resulted in the actual completion of a system for the automatic generation of persuasive discourse plans

Creating Responsive Information Systems with the Help of SSADM

In this paper, a program for a research is outlined. Firstly, the concept of responsive information systems is defined and then the notion of the capacity planning and software performance engineering is clarified. Secondly, the purpose of the proposed methodology of capacity planning, the interface to information systems analysis and development methodologies (SSADM), the advantage of knowledge-based approach is discussed. The interfaces to CASE tools more precisely to data dictionaries or repositories (IRDS) are examined in the context of a certain systems analysis and design methodology (e.g. SSADM)