Analysing Stream Authentication Protocols in Autonomous Agent-Based Systems

In stream authentication protocols used for large-scale data dissemination in autonomuous systems, authentication is based on the timing of the publication of keys, and depends on trust of the receiver in the sender and belief on whether an intruder can have prior knowledge of a key before it is published by a protocol. Many existing logics and approaches have successfully been applied to specify other types of authentication protocols, but most of them are not appropriate for analysing stream authentication protocols. We therefore consider a fibred modal logic that combines a belief logic with a linear-time temporal logic which can be used to analyse time-varying aspects of certain problems. With this logical system one is able to build theories of trust for analysing stream authentication protocols, which can deal with not only agent beliefs but also the timing properties of an autonomous agent-based system

Solving fuzzy linear regression with hybrid optimization

Fuzzy linear regression is an important tool to find the linear inexact relationship between uncertain data. We then propose a hybrid optimization method based on tabu search and harmony search as a potential way of solving fuzzy linear regression. The proposed method aims at finding a model without considering any mathematical constraints while reducing the error of the regression’s model in comparison to other methods. The experimental comparison of the results for two classes of crisp input-fuzzy output and fuzzy input-fuzzy output data sets shows the superiority of the method over the existing ones.8 page(s

A Least square approach for the detection and removal of outliers for fuzzy linear regressions

Fuzzy linear analysis may lead to an incorrect interpretation of data in case of being incapable of dealing with outliers. Both basic probabilistic and least squares approaches are sensitive to outliers. In order to detect the outliers in data, we propose a two stage least squares approach which in contrast to the other proposed methods in the literature does not have any user defined variables. In the first stage of this approach, the outliers are detected and the clean dataset is prepared and then in the second stage a model is sought to fit the clean dataset. In both the first and second phases, the minimization of the model fitting measurement is achieved with hybrid optimization which gives us the flexibility of using any type of a model fitting measure regardless of being continuous or differentiable.6 page(s

Approaches for semantic interoperability between domain ontologies

Domain ontologies and knowledge-based systems have become very important in the agent and semantic web communities. As their use has increased, providing means of resolving semantic differences has also become very important. In this paper we survey the approaches that have been proposed for providing interoperability among domain ontologies. We also discuss some key issues that still need to be addressed if we were to move from semi to fully automated approaches to provide consensus among heterogeneous ontologies.10 page(s

Context-aware trust management for peer-to-peer mobile ad-hoc networks

Mobile ad hoc networks (MANETs) are self-organizing and adaptive, and securing such networks is non-trivial. Most security schemes suggested for MANETs tend to build upon some fundamental assumptions regarding the trustworthiness of the participating hosts and the underlying networking systems without presenting any definite scheme for trust establishment. If MANET is to achieve the same level of acceptance as traditional wired and wireless network, then a formal specification of trust and a framework for trust management must become an intrinsic part of its infrastructure. The goal of this paper is to highlight issues relating to trust in MANETs and describe a context-aware, reputation-based approach for establishing trust that assesses the trustworthiness of the participating nodes in a dynamic and uncertain MANET environment.6 page(s