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The purpose of this paper is to demonstrate the use of Petri nets in a job shop setup for the improvement in the utilization of machines.

The study discusses concepts such as reachable state, token and matrix equations set, and demonstrates the improvements in machines’ utilization in a job shop. It makes use of algorithms to generate reachable markings to obtain utilization. The study not only describes the application of theory, but also extends the body of knowledge on Petri nets and job shops.

In this study, machines’ utilization has been studied in a job shop with six machines and eight products. The study finds that substantial utilization improvement in job shop set up can be obtained through the application of Petri nets. The study also exposes that Petri nets are mostly used for machines, jobs and tools scheduling problems, but its use in machines’ utilization is neglected. The framework and application presented here along with generalizable findings, is the first to report about machine utilization improvement in job shop manufacturing environment.

Job shops are characterized by high unit production cost, low investments, low volume and high variety, complex flows, flexible and skilled work force, general purpose machines, high material handling; resulting in poor utilization of machines. Therefore, the findings of this study can help in reducing such costs through better machine utilization. This can help in increasing the competitiveness of the companies.

The contribution of study lies in investigating and improving stage wise utilization in a job shop setup. It has never been reported before.

The purpose of this paper is to propose a model for a two-agent multi-target-searching scenario in a two-dimensional region, where some places of the region have limited resource capacity in terms of the number of agents that can simultaneously pass through those places and few places of the region are unreachable that expand with time. The proposed cooperative search model and Petri net model facilitate the search operation considering the constraints mentioned in the paper. The Petri net model graphically illustrates different scenarios and helps the agents to validate the strategies.

In this paper, the authors have applied an optimization approach to determine the optimal locations of base stations, a cooperative search model, inclusion–exclusion principle, Cartesian product to optimize the search operation and a Petri net model to validate the search technique.

The proposed approach finds the optimal locations of the base stations in the region. The proposed cooperative search model allows various constraints such as resource capacity, time-dependent unreachable places/obstacles, fuel capacities of the agents, two types of targets assigned to two agents and limited sortie lengths. On the other hand, a Petri net model graphically represents whether collisions/deadlocks between the two agents are possible or not for a particular combination of paths as well as effect of time-dependent unreachable places for different combination of paths are also illustrated.

The problem addressed in this paper is similar to various real-time problems such as rescue operations during/after flood, landslide, earthquake, accident, patrolling in urban areas, international borders, forests, etc. Thus, the proposed model can benefit various organizations and departments such as rescue operation authorities, defense organizations, police departments, etc.

To the best of the authors’ knowledge, the problem addressed in this paper has not been completely explored, and the proposed cooperative search model to conduct the search operation considering the above-mentioned constraints is new. To the best of the authors’ knowledge, no paper has modeled time-dependent unreachable places with the help of Petri net.

Business process models, while primarily intended for process documentation, communication, and improvement, are often also used as input for developing process-oriented software systems (Ouyang et al., 2009). Ensuring correctness, handling complexity, and improving reusability and maintainability of business process models are important for all these goals. The purpose of this paper is to propose an aspect-oriented business process modeling and correctness controlling method based on Petri nets to satisfy these goals.

The aspect-oriented paradigm provides a proper mechanism to modularization, and thus reduces the complexity of models, and also improves reusability and maintainability. However, weaving aspects into base processes may bring in mistakes or errors. To ensure correctness of modeling, this paper presents a formal approach to modeling aspect-oriented business processes and a method to ensure modeling correctness. Petri net is used as the process modeling language and its analysis techniques are applied to analyze the correctness of modeling. Two types of correctness, specifically, aspect-aspect correctness and base-aspect correctness are analyzed. A real banking process model is studied systematically in the case study to evaluate the approach and the performance assessments are conducted to show the cost and effect of the approach.

Designing aspect-oriented business process models help organizations reusing the model elements to reduce redundancy of their model repository, improving their maintainability, and supporting them to adapt to the changes of business requirements with flexible modeling. It is important to stress that the correctness of business process modeling is important in ensuring the quality of the models, especially in the safety-critical business domains, such as financial business domain.

In this paper, separation of concerns is used to separate the cross-cutting activities and core activities in accordance with the different functions of these activities, and an approach to modeling aspect-oriented business processes is proposed. First, the cross-cutting activities are encapsulated as aspects, while core business activities are modeled as base processes. Then, according to the correctness requirements of business process models, based on the weaving mechanisms of aspect-oriented approach, weaving correctness is defined. Weaving correctness controlling methods between multi-aspects and between aspects and base processes are designed. Errors or mistakes of aspect-oriented business process modeling are prevented during the procedure of modeling to ensure error-free business process modeling.

The healthcare industry is facing several challenges such as the reduction of costs and quality improvement of the provided services. Engineering studies could be very useful in supporting organizational and management processes. Healthcare service efficiency depends on a strong collaboration between clinical and engineering experts, especially when it comes to analyzing the system and its constraints in detail and subsequently, when it comes to deciding on the reengineering of some key activities. The purpose of this paper is to propose a case study showing how a mix of representation tools allow a Manager of a Radiology Department to solve some human and technological resource re‐organizational issues, which have to be faced due to the introduction of a new technology and a new portfolio of services.

In order to simulate the activities within the radiology department and examine the relationship between human and technological resources, different visual diagrammatic language (VDL) techniques have been implemented to get knowledge about the heterogeneous factors related to the healthcare service delivery. In particular, flow charts, IDEF0 diagrams and Petri nets have been integrated each other with success as a modelisation tools.

The simulation study performed through the application of the aforementioned VDL techniques suggests the opportunity of re‐organizing the nurse activities within the radiology department.

The re‐organization of a healthcare service and in particular of a radiology department by means of joint flow charts, IDEF0 diagrams and Petri nets is a poorly investigated topic in literature. This paper demonstrates how flow charts and IDEF0 can help people working within the department to understand the weak points of their organization and constitute an efficient base of knowledge for the implementation of a Petri net aimed at improving the departmental performance.

This paper aims to propose a methodology based on Petri nets to evaluate the reliability characteristics of the pulping system of a paper industry in a realistic working environment. The effects of occurrence of failure/course of actions and availability of repair facilities on system performance have been investigated.

Stochastic Reward Nets (SRN), an extension of Petri nets, are applied to model the interactions among the active/standby units of the system and reliability parameters have been evaluated using Monte Carlo simulation.

The methodology adopted in this paper provides a better understanding of the behavior of the system under varying operating conditions. Reliability analysis of a pulping system of a paper industry presented in this paper will help the management in deciding upon the maintenance strategy to be adopted to improve the performance of the system and consequently reduce the operation and maintenance cost.

The application of the proposed technique will not only help the reliability engineers/managers/system engineers to understand the dynamic behavior of complex systems but also helps to plan/adapt suitable maintenance policies to improve system reliability/availability.

This paper seeks to propose a methodology based on Petri nets to evaluate the reliability parameters of a screening system in paper industry. The effects of failures and courses of action on the system performance have also been investigated.

Generalized stochastic Petri nets (GSPN), a class of Petri nets, has been used to model the interactions amongst the active/standby units of the system; and Markovian approach has been used to evaluate the reliability parameters. The data related to equipments' operational behavior were collected, processed and quantified. Using the data, reliability analysis of system in the long run conditions has been carried out. The sensitivity analysis has been performed to study the effect of failure/repair rates of each unit of the system on system performance.

The methodology adopted in this paper provides a better understanding on the behavior of the system through its graphical representation. The reachability graph generated with Petri net model helps to identify the state space evolution of the system.

Reliability analysis of a screening system of the paper industry presented in this paper will help management in deciding upon the maintenance strategy to be adopted with the objective of improving the performance of the system and consequently reducing the operational and maintenance costs.

Many features constitute an adaptive system such as user model, interface specification, business functionalities and service implementation. Context awareness is an important facet of service oriented application creation dealing with the gathering, use and representation of context information. Generally, user interfaces and services communities work separately on the adaptation process and do not converge. The aim of this work is to manage the system’s functionalities and the user interface that delivers data to the relevant consumer early since the design phase until the code generation.

The authors discuss how a unified method based on a model-driven architecture for adaptive user interface and pervasive service creation eases the work of designers and developers, limits incompatibility issues and supports dynamic generation of systems adapted to different contexts of use.

The proposed approach is able to support a semi-automatic ubiquitous application generation with service, behavior, presentation and content adaptation.

In this paper, the authors tackle context-awareness at two levels: system functionalities and user interface generation. The authors also tackle adaptation at the specification and implementation levels.

Computers and the information they process are critical to many organizations’ ability to perform their mission and business functions. It therefore makes sense that executives view computer security as a management issue and seek to protect their data which are stored in these computers. Presents a main objective of introducing a modeling design and verification of the monitoring part of common intrusion detection framework (CIDF) using Petri Nets. To enhance the security of a system by monitoring system activity and detecting a typical behavior, statistical unusual behavior must be found in the observation of the system. Such a monitoring system will be capable of detecting intrusion that could not be detected by any other means. These systems that do collect audit data are the only way to build a real secure system which is the most important part of the network. Presents a proposed model of the monitoring part of the CIDF based on Petri Nets modeling technique. Tests the proposed model using the Petri Nets properties.

Considers an integrated approach to maintenance management, based on the development of an advanced machine tool failure diagnosis and recovery system. Outlines how such systems can be utilized to effectively monitor the ever more complicated machining facilities used in modern manufacturing. Illustrates how a Petri‐net based system has been developed to meet the needs of a modern computer‐based maintenance facility and the potential that such systems provide in a move towards total productive maintenance. Deals with the steps taken to ensure that such a system can be successfully deployed, and considers how the resulting integrated maintenance management system can benefit existing users of advanced manufacturing technology.

Describes the ongoing development of a Petri‐Net‐based machine tool failure diagnosis system. The described system incorporates condition monitoring systems and expert system‐based diagnostic tools. Brings these together with the Petri‐Net monitoring system to form an integrated fault location and rectification package and an associated maintenance management system.