جستجوی مقالات مرتبط با کلیدواژه « شبکه پتری رنگی » در نشریات گروه « برق »

Cloud computing is a new technology which its popularity increases every day, a popularity due to its elasticity. On the other words, cloud computing takes into account an unlimited capacity of the resource for the consumer, and the consumer can take resources in demand based on competitive rates and increase or decrease the amount of resources. There have been many improvements to elasticity management by previous researches. However, further reasearches are necessary to manage elasticity more efficiently. In this paper, a model for the elasticity improvement using a colored Petri network is proposed to provide resources in cloud computing. In the proposed model, elasticity management is performed using a colored Petri net in the form of control of the M/M/N queues. In this way, there is a horizontal queue for each request or service in the vertical queue for the need to increase or decrease the virtual machine. The results of the proposed method show an improvment in elasticity, accuracy and speed, compared with the other approaches.

Digital switches are one of the main components of the data transmission networks, and their modeling in applications such as traffic measurement, fault diagnosis, and operator training,have significant importance. In this paper, signaling of a digital switch is modeled and simulatedusing Colored Petri Nets. Colored PetriNet can support various data types and due to its intuitive graphical representationis known as an efficient tool for modeling of Discrete Event Systems (DES). In this papera digital switch is considered as a DES and its signaling is modeled using a CPN. Signalingis a sustainable and comprehensiveprotocol that can integrate various communication services into digital and analog telephone subscribers. The protocol cited in this paper,meets all the requirements for communication between digital databases and its role in the communications system is the same as one in computer networks. In this paper the signaling state is limited to a successful call between twosubscribers. In addition, the reachability graph is extracted for the CPN which contains all possible events in the DES and can be used for supervisory control tasks such as fault diagnosis process.

Any concurrent transaction should be taken in database could lead to conflict. The conflict occurs due to incorrect values for the data which lead to interference in executed transaction which has been taken. The concurrency control algorithms, to insure the concurrent action many transactions has been designed to work concurrently with a common data. In this paper, Wound-Wait and Wait-Die concurrency control algorithms which are the part of preventing Deadlock techniques, has been modeled. Since the Colored Petri Net is one of the best methods in analyzing the concurrency control mechanism, modeling are shown using Colored Petri. Ater modeling the evaluation is carried out using parameters such as the number of transactions entering the system, the number of commands, and the number of relevant and irrelevant data between transactions, and the number of relevant data in transactions without irrelevant data, has been taken place. After evaluation, according to mentioned parameters, this result has been obtained, that Wound-Wait algorithm has much better time performance in comparison with the Wait-Die algorithm.

Existence of design faults is a source of failure in the system. Detection and removal of faults in design phase prohibits increase of cost and time of system development. Formal methods are used for proving behavioral properties of systems. Formal methods can be used in crux design of computer games to ensure absence of deadlock, guarantee of answer's existence and to determine complexity of crux. Hierarchical colored Petri net is a formal method that can be used to evaluate cruxes of computer games such as path planning puzzle games. Unblock me game is modeled as a case study and automatic analysis of its two cruxes are studied in this paper. Modeling of game is done hierarchically. New approaches for eliminating state space explosion problem and decreasing running time of model is presented in this paper. Modeling is done with aim of automatic state space analysis of the system and required functions for proving behavioral properties are implemented. This paper is presented a method for modeling and proving behavioral properties of puzzle type computer games using hierarchical colored Petri net that and can be generalized to similar games.