Search results for "Systems modeling"
showing 10 items of 18 documents
Reduction of UML Class Diagrams
2002
One and the same “real world” can be modeled by different UML class diagrams, which in such a case can be considered “intuitively equivalent”. A formalization of this “intuitive equivalence” of class diagrams is proposed. An algorithm is constructed that for two class diagrams determines if they model the same “real world”. This algorithm can be used in CASE tools to compare alternative models of a system, and for diagram “compression” to facilitate understanding of large diagrams.
Estimation des performances, test et contrôle des systèmes cyber-physiques employant des réseaux de communication non idéaux
2020
Wireless technology is a key enabler of the promises of Industry 4.0 (Smart Manufacturing). As such, wireless technology will be adopted as a principal mode of communication within the factory beginning with the factory enterprise and eventually being adopted for use within the factory workcell. Factory workcell communication has particular requirements on latency, reliability, scale, and security that must first be met by the wireless communication technology used. Wireless is considered a non-ideal form of communication in that when compared to its wired counterparts, it is considered less reliable (lossy) and less secure. These possible impairments lead to delay and loss of data in indus…
Introduction to: Enabling Collaborative Governance through Systems Modeling Methods
2020
This opening chapter sets out a structure for considering collaborative governance for public policy and managerial problem-solving through systemic principles, as well as through the use of group processes to facilitate agreement and buy-in in collective strategies. Such a collection of tools, techniques, and frameworks is needed to establish the value of these approaches and to accelerate their dissemination through the field.
Formal Modeling and Discrete-Time Analysis of BPEL Web Services
2008
International audience; Web services are increasingly used for building enterprise information systems according to the Service Oriented Architecture (SOA) paradigm. We propose in this paper a tool-equipped methodology allowing the formal modeling and analysis of Web services described in the BPEL language. The discrete-time transition systems modeling the behavior of BPEL descriptions are obtained by an exhaustive simulation based on a formalization of BPEL semantics using the Algebra of Timed Processes (ATP). These models are then analyzed by model checking value-based temporal logic properties using the CADP toolbox. The approach is illustrated with the design of a Web service for GPS na…
Unified Modeling Language
2005
Mature engineering disciplines are generally characterized by accepted methodical standards for describing all relevant artifacts of their subject matter. Such standards not only enable practitioners to collaborate, but they also contribute to the development of the whole discipline. In 1994, Grady Booch, Jim Rumbaugh, and Ivar Jacobson joined together to unify the plethora of existing object-oriented systems engineering approaches at semantic and notation level (Booch, 2002; Fowler, 2004; Rumbaugh, Jacobson, & Booch, 1998). Their effort led to the Unified Modeling Language (UML), a well-known, general-purpose, tool-supported, process-independent, and industry-standardized modeling lang…
Neural network approach to solving fuzzy nonlinear equations using Z-numbers
2020
In this article, the fuzzy property is described by means of the Z-number as the coefficients and variables of the fuzzy equations. This alteration for the fuzzy equation is appropriate for system modeling with Z-number parameters. In this article, the fuzzy equation with Z-number coefficients and variables is tended to be used as the models for the uncertain systems. The modeling issue related to the uncertain system is to obtain the Z-number coefficients and variables of the fuzzy equation. Nevertheless, it is extremely hard to get the Z-number coefficients of the fuzzy equations. In this article, in order to model the uncertain nonlinear systems, a novel structure of the multilayer neura…
A fast BEM for the analysis of damaged structures with bonded piezoelectric sensors
2010
A fast boundary element method for the analysis of three-dimensional solids with cracks and adhesively bonded piezoelectric patches, used as strain sensors, is presented. The piezoelectric sensors, as well as the adhesive layer, are modeled using a 3D state-space finite element approach. The piezoelectric patch model is formulated taking into account the full electro-mechanical coupling and embodying the suitable boundary conditions and it is eventually expressed in terms of the interface variables, to allow a straightforward coupling with the underlying host structure, which is modeled through a 3D dual boundary element method, for accurate analysis of cracks. The technique is computationa…
Estimation of brain connectivity through Artificial Neural Networks
2019
Among different methods available for estimating brain connectivity from electroencephalographic signals (EEG), those based on MVAR models have proved to be flexible and accurate. They rely on the solution of linear equations that can be pursued through artificial neural networks (ANNs) used as MVAR model. However, when few data samples are available, there is a lack of accuracy in estimating MVAR parameters due to the collinearity between regressors. Moreover, the assessment procedure is also affected by the lack of data points. The mathematical solution to these problems is represented by penalized regression methods based on l 1 norm, that can reduce collinearity by means of variable sel…
IMPROVEMENTS IN THE SYSTEMS-BASED MODELS GENERATOR SIGEM
1994
Program generators, for us, are computer programs that produce other computer programs. SIGEM is an expert system program generator that can help in the modeling process of real systems. It is associated with a methodology well adapted to modeling practice. In this paper, we present and compare this methodology with other similar ones. Static models (databases), dynamic models, rule-based expert systems, literal and/or numerical variables, probabilistic uncertainty in data and in functions, dimensioned variables, discrete event simulation, and other related problems can be treated with this methodology. We suggest a systems modeling methodology and a programming tool to increase generality …
Concept of Client-Server Environment for Agent-Based Modeling and Simulation of Living Systems
2015
In the paper a concept for integrated and simple-to-use agent-based modeling and simulation environment is presented. The modeling environment allows simulating massive agent-based systems. Modeling environment itself is not domain specific, but it is expandable and allows creating domain-specific models. Hierarchical environment structure is supported. Individual agents could evolve by its individual path and pace. We use the General Living Systems theory as a reference model to check whether proposed modeling and simulation environment may also be used to describe models of living systems that are most complex systems around. The main concepts of proposed modeling environment such as agen…