254,748 research outputs found
A survey of agent-oriented methodologies
This article introduces the current agent-oriented methodologies. It discusses what approaches have been followed (mainly extending existing object oriented and knowledge engineering methodologies), the suitability of these approaches for agent modelling, and some conclusions drawn from the survey
Globally reasoning about localised security policies in distributed systems
In this report, we aim at establishing proper ways for model checking the
global security of distributed systems, which are designed consisting of set of
localised security policies that enforce specific issues about the security
expected.
The systems are formally specified following a syntax, defined in detail in
this report, and their behaviour is clearly established by the Semantics, also
defined in detail in this report. The systems include the formal attachment of
security policies into their locations, whose intended interactions are trapped
by the policies, aiming at taking access control decisions of the system, and
the Semantics also takes care of this.
Using the Semantics, a Labelled Transition System (LTS) can be induced for
every particular system, and over this LTS some model checking tasks could be
done. We identify how this LTS is indeed obtained, and propose an alternative
way of model checking the not-yet-induced LTS, by using the system design
directly. This may lead to over-approximation thereby producing imprecise,
though safe, results. We restrict ourselves to finite systems, in the sake of
being certain about the decidability of the proposed method.
To illustrate the usefulness and validity of our proposal, we present 2 small
case-study-like examples, where we show how the system can be specified, which
policies could be added to it, and how to decide if the desired global security
property is met.
Finally, an Appendix is given for digging deeply into how a tool for
automatically performing this task is being built, including some
implementation issues. The tool takes advantage of the proposed method, and
given some system and some desired global security property, it safely (i.e.
without false positives) ensures satisfaction of it
Recommended from our members
Analysing children's accounts using discourse analysis
Discourse analytic approaches to research depart from understandings of the individual and of the relation between language and knowledge provided by positivist and post-positivist approaches. This chapter sets out to show what this might mean for studying childrenās experiences through, for example, interview-based research, and how a discourse analytic approach may bring into play conceptual resources that are particularly valuable for research with children. First and foremost, discursive approaches highlight the interpretive nature of any research, not only that with children. As a consequence, they challenge the conventional distinction between data collection and analysis, question the status of research accounts and encourage us to question taken-for-granted assumptions about distinctions between adults and children. Hence our emphasis in this chapter is on the active and subjective involvement of researchers in hearing, interpreting and representing childrenās āvoicesā
Computer-Aided System for Wind Turbine Data Analysis
Context: The current work on wind turbine failure detection focuses on researching suitable signal processing algorithms and developing efficient diagnosis algorithms. The laboratory research would involve large and complex data, and it can be a daunting task.
Aims: To develop a Computer-Aided system for assisting experts to conduct an efficient laboratory research on wind turbine data analysis. System is expected to provide data visualization, data manipulation, massive data processing and wind turbine failure detection.
Method: 50G off-line SCADA data and 4 confident diagnosis algorithms were used in this project. Apart from the instructions from supervisor, this project also gained help from two experts from Engineering Department. Java and Microsoft SQL database were used to develop the system.
Results: Data visualization provided 6 different charting solutions and together with robust user interactions. 4 failure diagnosis solutions and data manipulations were provided in the system. In addition, dedicated database server and Matlab API with Java RMI were used to resolve the massive data processing problem.
Conclusions: Almost all of the deliverables were completed. Friendly GUI and useful functionalities make user feel more comfortable. The final product does enable experts to conduct an efficient laboratory research. The end of this project also gave some potential extensions of the system
Cognitive modelling of language acquisition with complex networks
ABSTRACT Cognitive modelling is a well-established computational intelligence tool, which is very useful for studying cognitive phenomena, such as young children's first language acquisition. Specifically, linguistic modelling has recently benefited greatly from complex network theory by modelling large sets of empirical linguistic data as complex networks, thereby illuminating interesting new patterns and trends. In this chapter, we show how simple network analysis techniques can be applied to the study of language acquisition, and we argue that they reveal otherwise hidden information. We also note that a key network parameter -the ranked frequency distribution of the links -provides useful knowledge about the data, even though it had been previously neglected in this domain
- ā¦