Image segmentation has been used widely for detection and extraction of objects in digital images. Thresholding is one of the effective image segmentation techniques. Fuzzy 2-partition entropy is used effectively for the selection of threshold value. Fuzzy 2-partition entropy required the optimization of some parameters for the selection of threshold value. Teaching-Learning-Based Optimization (TLBO) algorithm has been applied on fuzzy 2-partition entropy to find these parameters and subsequent threshold value. Normally, fuzzy 2-partition Shannon entropy is used for thresholding. In the proposed research work, fuzzy 2-partition Kapur entropy is explored for the evaluation of its potential for selecting optimal threshold value using TLBO algorithm. The present work measures the performance comparison of fuzzy 2-partition Kapur entropy using TLBO with fuzzy 2-partition Shannon entropy using TLBO. The experiments are carried out on standard test images from benchmark dataset. Peak signal to noise ratio, uniformity and structural similarity index are the three different measures which have been used to compare the performance. Results demonstrate that the performance of fuzzy 2-partition Kapur entropy using TLBO is quite promising.

Most network intruders launch their attacks through stepping-stones to reduce the risks of being discovered. To uncover such intrusions, one prevalent, challenging, and critical way is to compare an incoming connection with outgoing connections to determine if a computer is used as a stepping-stone. In this paper, we present a way by using signal processing technology-correlation coefficient, such as Spearman Rank, Kendall Tau Rank, and Pearson Product-Moment, to correlate two sessions to identify stepping-stone intrusions. The contribution of this paper is that we are the first one to apply correlation coefficient to stepping-stone intrusion detection, and more importantly, it is not necessary to monitor a session for a long time to conclude a stepping-stone intrusion. The experiment results showed that a step-ping-stone intrusion can be detected while an intruder input the username and password. Further work needs to be done to test if this approach could resist intruders' evasion.

In this paper, we identify that protocol verification using invariants have significant limitations such as inapplicability to some protocols, non-standard attacker inferences and non-free term algebras. We argue that constraint solving for bounded process analysis can be used in conjunction with decidability of context-explicit protocols as a verification tool and can overcome those limitations. However, this is possible only when new decidability results are obtained for protocol security, especially in presence of non-standard inferences and non-free term algebras.

This article discusses the use of Petri nets to model the process of object matching between an image and a model under different two-dimensional geometric transformations. This transformation finds its applications in sensor-based robot control, flexible manufacturing systems, industrial inspection, and so on. Its topological structure relation, called point-line relation structure (PLRS), presents a Petri net-based description approach for object structure. It has been shown how Petri nets can be used to model the matching process, and an optimal or near optimal matching can be obtained by tracking the reachability graph of the net. The experiment result shows that objects can be successfully identified and located under two-dimensional transformation such as translations, rotations, scale changes, and distortions due to partial object occlusion. © 2002 Wiley Periodicals, Inc.

Software prototyping offers a fast, flexible and cost-effective alternative to physical prototyping during the analysis and design stages of commercial electronic products. This paper describes a software platform implemented to facilitate the virtual prototyping of cellular phone models at the analysis and design stages. In order to discuss the application of the platform, an example of a basic cellular phone is considered. The features and functions of a standard cellular phone have been implemented as primitives in a Parts library, and its behavioural characteristics can be dynamically simulated via script files. The prototyping platform provides modularity, and requires minimal implementation effort to accommodate new cellular phone model specifications. In addition, the platform is able to demonstrate the practical usefulness of software prototyping in reducing the complexity of product analysis and design. Copyright © 1999 John Wiley & Sons, Ltd.

A graphical-user-interface (GUI) for a Modeling Assisted Software Environment (MASE) tool based on Petri nets is proposed. The MASE tool is a hierarchical object-oriented Petri net package. The proposed package allows the creation, moving, erasing and alignment of objects, creation of sub and super-nets, etc. by mouse clicking. Further, automatic and manual simulation are also supported by popping up of an execution panel. It supports T-timed Petri nets, high level Petri nets and is proposed to include other extended models in it to make a more generic platform of system design. The interpretations of the Petri net can be added by using MASE language. After the execution of the Petri-net, a pseudo-code will be generated based on the system drawn. The tool also supports various analysis properties like safety, boundedness, deadlock, etc. Other properties can easily be included in the analysis library (a future plan).>

A rule-based design methodology for solving control problems is presented. For the representation of various constraints, activities, and other dependency properties of the control problem, abstract Petri nets (APNs) which are an extended form of Petri net modeling are used as a specification and formalism tool which can be analyzed using the analysis techniques of Petri-net-based models. The APN provides a compact, consistent, and verifiable description of the dynamic behaviour of the system under consideration in a structured mode. The proposed design methodology supports specification, validation, and analysis through high-level interaction with the modeled system. The various steps which were taken towards the development of such a design paradigm are explained. An example which shows the APN modeling of an elevator system is given.>

The authors exploit the concepts of Petri nets for the modeling of databases through a meaningful interpretation of various database structures. This has been achieved using, specifically, the reachability and conflict concepts of Petri nets. The concept of conflict has been given a mathematical interpretation to suit its applications to database structures. Starting with a network structure, a new class of application for the reachability equation has been proposed. Based upon this, an algorithm has been postulated to access the data paths between any two specified nodes in the database model. The goal is to provide useful data for the design of databases.