9,254 research outputs found
Mapping Fuzzy Petri Net to Fuzzy Extended Markup Language
Use of model gives the knowledge and information about the phenomenon also eradicates the cost, the effort and the hazard of using the real phenomenon. Characteristics and concepts of Petri nets are in a way that makes it simple and strong to describe and study the information processing system; especially it is shown in those which are dealing with discrete, concurrent, distributed, parallel and indecisive events. Yet, due to Petri nets inability to face with systems working on obscure data and continues events, the interest to develop fundamental concept of Petri nets has been raised which is led to new style of presented model named "fuzzy Petri nets". The difference in Petri nets is in the elements that have been fuzzed. Transitions, places, signs and arcs can be fuzzed. PMNL, on the other hand as a markup language has been engaged in uttering Petri nets in previous researches. Fuzzy markup nets can model the uncertainty of concurrent scenarios different from a dynamic system by a board of parameters and use of fuzzy membership dependencies. Therefore, in order to define these uncertain data, it is vital to use a formal language to describe fuzzy Petri nets. To support this version in this thesis, a markup language will be presented stating the structure and grammar of markup language and covering fuzzy concepts in Petri nets as well. Presenting the suggested grammar accommodates the support of fuzzy develope.DOI:http://dx.doi.org/10.11591/ijece.v3i5.403
Pemodelan Sistem Antrian Di Salah Satu Cabang Bank X Dengan Menggunakan Coloured Petri Nets
Salah satu permasalahan sistem event diskrit adalah sistem antrian pada
bank, yang menunjukkan kedatangan nasabah, lama nasabah dilayani hingga
nasabah selesai dilayani dan meninggalkan bank. Sistem antrian pada bank dapat
dimodelkan menggunakan Coloured Petri Nets. Coloured Petri Nets merupakan
gabungan dari Petri net dengan bahasa pemrograman yang dikembangkan oleh Kurt
Jensen. Pada penelitian ini, dibahas bagaimana memodelkan sistem antrian di salah
satu cabang Bank X menggunakan Coloured Petri Nets dan Timed Coloured Petri
Nets. Selanjutnya data yang diperoleh diolah secara statistik, dengan menentukan
distribusi data yang sesuai. Penentuan distribusi data menggunakan uji normalitas.
Jika hasil uji normalitas data menunjukkan data normal maka digunakan distribusi
normal, namun jika hasil uji normalitas menunjukkan data tidak normal maka
digunakan distribusi yang lainnya dalam hal ini yaitu distribusi eksponensial
dan distribusi Weibull. Nilai estimasi parameter dari masing-masing distribusi
diperoleh dengan menggunakan metode Maximum Likelihood Estimation (MLE).
Nilai tersebut digunakan sebagai parameter pada Timed Coloured Petri Nets
(TCPN). Hasil simulasi dari TCPN menunjukkan bahwa jumlah teller yang optimal
dalam melayani nasabah adalah empat orang. Selain itu Timed Coloured Petri
Nets dapat menunjukkan jumlah nasabah yang dilayani dan waktu pelayanannya.
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One of the problems in discrete event systems is queuing system at the bank,
which shows the arrival of customers, the waiting time, the service time and
departure the bank. A queue at the bank system can be modeled using coloured Petri
nets. Coloured Petri Nets is a combination of Petri net with programming language
which is developed by Kurt Jensen. In this study, we construct a model of queues at
Bank X using coloured Petri Nets and Timed Colored Petri Nets. Then, observation
data is processed to obtain appropriate statistical distribution. In this thesis, the data
has statistical distribution: normal, Weibull and Exponensial based on the distribution
testing. The estimation of parameter is determined by Maximum Likelihood
Estimation Method. The acquired estimation value will be used as parameters in the
queue model using Timed Colored Petri Nets. According to the simulation, Timed
Coloured Petri Nets show that the optimum number of tellers to serve the customers
are four. Furthermore, Timed Coloured Petri Nets also show the customer numbers
and service time
Integration of an object formalism within a hybrid dynamic simulation environment
PrODHyS is a general object-oriented environment which provides common and reusable components designed for the development and the management of dynamic simulation of systems engineering. Its major characteristic is its ability to simulate processes described by a hybrid model. In this framework, this paper focuses on the "Object Differential Petri Net" (ODPN) formalism integrated within PrODHyS. The use of this formalism is illustrated through a didactic example relating to the field of Chemical Process System Engineering (PSE)
ADAM: Analysis of Discrete Models of Biological Systems Using Computer Algebra
Background: Many biological systems are modeled qualitatively with discrete
models, such as probabilistic Boolean networks, logical models, Petri nets, and
agent-based models, with the goal to gain a better understanding of the system.
The computational complexity to analyze the complete dynamics of these models
grows exponentially in the number of variables, which impedes working with
complex models. Although there exist sophisticated algorithms to determine the
dynamics of discrete models, their implementations usually require
labor-intensive formatting of the model formulation, and they are oftentimes
not accessible to users without programming skills. Efficient analysis methods
are needed that are accessible to modelers and easy to use. Method: By
converting discrete models into algebraic models, tools from computational
algebra can be used to analyze their dynamics. Specifically, we propose a
method to identify attractors of a discrete model that is equivalent to solving
a system of polynomial equations, a long-studied problem in computer algebra.
Results: A method for efficiently identifying attractors, and the web-based
tool Analysis of Dynamic Algebraic Models (ADAM), which provides this and other
analysis methods for discrete models. ADAM converts several discrete model
types automatically into polynomial dynamical systems and analyzes their
dynamics using tools from computer algebra. Based on extensive experimentation
with both discrete models arising in systems biology and randomly generated
networks, we found that the algebraic algorithms presented in this manuscript
are fast for systems with the structure maintained by most biological systems,
namely sparseness, i.e., while the number of nodes in a biological network may
be quite large, each node is affected only by a small number of other nodes,
and robustness, i.e., small number of attractors
Dynamic state reconciliation and model-based fault detection for chemical processes
In this paper, we present a method for the fault detection based on the residual generation. The main idea is to reconstruct the outputs of the system from the measurements using the extended Kalman filter. The estimations are compared to the values of the reference model and so, deviations are interpreted as possible faults. The reference model is simulated by the dynamic hybrid simulator, PrODHyS. The use of this method is illustrated through an application in the field of chemical processe
Towards a Notion of Distributed Time for Petri Nets
We set the ground for research on a timed extension of Petri nets where time parameters are associated with tokens and arcs carry constraints that qualify the age of tokens required for enabling. The novelty is that, rather than a single global clock, we use a set of unrelated clocks --- possibly one per place --- allowing a local timing as well as distributed time synchronisation. We give a formal definition of the model and investigate properties of local versus global timing, including decidability issues and notions of processes of the respective models
Integration of a failure monitoring within a hybrid dynamic simulation environment
The complexity and the size of the industrial chemical processes induce the monitoring of a growing number of process variables. Their knowledge is generally based on the measurements of system variables and on the physico-chemical models of the process. Nevertheless this information is imprecise because of process and measurement noise. So the research ways aim at developing new and more powerful techniques for the detection of process fault. In this work, we present a method for the fault detection based on the comparison between the real system and the reference model evolution generated by the extended Kalman filter. The reference model is simulated by the dynamic hybrid simulator, PrODHyS. It is a general object-oriented environment which provides common and reusable components designed for the development and the management of dynamic simulation of industrial systems. The use of this method is illustrated through a didactic example relating to the field of Chemical Process System Engineering
Hybrid Petri net model of a traffic intersection in an urban network
Control in urban traffic networks constitutes an important and challenging research topic nowadays. In the literature, a lot of work can be found devoted to improving the performance of the traffic flow in such systems, by means of controlling the red-to-green switching times of traffic signals. Different techniques have been proposed and commercially implemented, ranging from heuristic methods to model-based optimization. However, given the complexity of the dynamics and the scale of urban traffic networks, there is still a lot of scope for improvement. In this work, a new hybrid model for the traffic behavior at an intersection is introduced. It captures important aspects of the flow dynamics in urban networks. It is shown how this model can be used in order to obtain control strategies that improve the flow of traffic at intersections, leading to the future possibility of controlling several connected intersections in a distributed way
Model based fault diagnosis for hybrid systems : application on chemical processes
The complexity and the size of the industrial chemical processes induce the monitoring of a growing number of process variables. Their knowledge is generally based on the measurements of system variables and on the physico-chemical models of the process. Nevertheless, this information is imprecise because of process and measurement noise. So the research ways aim at developing new and more powerful techniques for the detection of process fault. In this work, we present a method for the fault detection based on the comparison between the real system and the reference model evolution generated by the extended Kalman filter. The reference model is simulated by the dynamic hybrid simulator, PrODHyS. It is a general object-oriented environment which provides common and reusable components designed for the development and the management of dynamic simulation of industrial systems. The use of this method is illustrated through a didactic example relating to the field of Chemical Process System Engineering
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