one of the most important preparation steps of co-management projects implementation is recognizing key actors at local community level. these actors can assist managers and planners as local leaders and social powers. by applying social network analysis and centrality index at actors’ level of “goormomenin” common rangeland, kalateh region, daamghan city in this research, social powers and loc...

This paper presents a mathematical framework for expressing trust management systems. The framework makes it easier to understand existing systems and to compare them to one another, as well as to design new systems. The framework defines the semantics of a trust management engine via a least fixpoint in a lattice, which, in some situations, leads to an efficient implementation. To demonstrate ...

nowadays organizations seriously search for their overall improvements with the aim of achieving to the organizational excellence. organizations can’t manage their programs efficiently without using comprehensive model due to examine and reform their programs. because of these needs and problems, in this thesis we are analyzing the performance management system at the department of the assessme...

Available online 8 March 2008 Cryptographic enforcement of access control mechanisms relies on encrypting protected data with the keys stored by authorized users. This approach poses the problem of the distribution of secret keys. In this paper, a key management scheme is presented where each user stores a single key and is capable of efficiently calculating appropriate keys needed to access re...

The health and functioning of coral reef ecosystems worldwide is in decline, and in the face of increasing anthropogenic stress, the rate of decline of these important ecosystems is set to accelerate. Mitigation strategies at regional scales are costly, but nevertheless critical, as reef systems are highly connected across regions by ocean transport of both larval propagules and pollutants. It ...

Trust Management represents a vital component for the protection of business transactions. This paper considers the application of a relational-based model for Trust Management in Electronic Payment Systems. We introduce a generic payment model that provides a good framework to validate our trust model. We use the special features, new extensions and relational techniques provided by the Trust ...

Modern Critical infrastructures have command and control systems. These command and control systems are commonly called supervisory control and data acquisition (SCADA). In the past, SCADA system has a closed operational environment, so these systems were designed without security functionality. Nowadays, as a demand for connecting the SCADA system to the open network growths, the study of SCAD...