5,775 research outputs found
Exploiting multi-agent system technology within an autonomous regional active network management system
This paper describes the proposed application of multi-agent system (MAS) technology within AuRA-NMS, an autonomous regional network management system currently being developed in the UK through a partnership between several UK universities, distribution network operators (DNO) and a major equipment manufacturer. The paper begins by describing the challenges facing utilities and why those challenges have led the utilities, a major manufacturer and the UK government to invest in the development of a flexible and extensible active network management system. The requirements the utilities have for a network automation system they wish to deploy on their distribution networks are discussed in detail. With those requirements in mind the rationale behind the use of multi-agent systems (MAS) within AuRA-NMS is presented and the inherent research and design challenges highlighted including: the issues associated with robustness of distributed MAS platforms; the arbitration of different control functions; and the relationship between the ontological requirements of Foundation for Intelligent Physical Agent (FIPA) compliant multi-agent systems, legacy protocols and standards such as IEC 61850 and the common information model (CIM)
Practical applications of data mining in plant monitoring and diagnostics
Using available expert knowledge in conjunction with a structured process of data mining, characteristics observed in captured condition monitoring data, representing characteristics of plant operation may be understood, explained and quantified. Knowledge and understanding of satisfactory and unsatisfactory plant condition can be gained and made explicit from the analysis of data observations and subsequently used to form the basis of condition assessment and diagnostic rules/models implemented in decision support systems supporting plant maintenance. This paper proposes a data mining method for the analysis of condition monitoring data, and demonstrates this method in its discovery of useful knowledge from trip coil data captured from a population of in-service distribution circuit breakers and empirical UHF data captured from laboratory experiments simulating partial discharge defects typically found in HV transformers. This discovered knowledge then forms the basis of two separate decision support systems for the condition assessment/defect clasification of these respective plant items
Industrial implementation of intelligent system techniques for nuclear power plant condition monitoring
As the nuclear power plants within the UK age, there is an increased requirement for condition monitoring to ensure that the plants are still be able to operate safely. This paper describes the novel application of Intelligent Systems (IS) techniques to provide decision support to the condition monitoring of Nuclear Power Plant (NPP) reactor cores within the UK. The resulting system, BETA (British Energy Trace Analysis) is deployed within the UK’s nuclear operator and provides automated decision support for the analysis of refuelling data, a lead indicator of the health of AGR (Advanced Gas-cooled Reactor) nuclear power plant cores. The key contribution of this work is the improvement of existing manual, labour-intensive analysis through the application of IS techniques to provide decision support to NPP reactor core condition monitoring. This enables an existing source of condition monitoring data to be analysed in a rapid and repeatable manner, providing additional information relating to core health on a more regular basis than routine inspection data allows. The application of IS techniques addresses two issues with the existing manual interpretation of the data, namely the limited availability of expertise and the variability of assessment between different experts. Decision support is provided by four applications of intelligent systems techniques. Two instances of a rule-based expert system are deployed, the first to automatically identify key features within the refuelling data and the second to classify specific types of anomaly. Clustering techniques are applied to support the definition of benchmark behaviour, which is used to detect the presence of anomalies within the refuelling data. Finally data mining techniques are used to track the evolution of the normal benchmark behaviour over time. This results in a system that not only provides support for analysing new refuelling events but also provides the platform to allow future events to be analysed. The BETA system has been deployed within the nuclear operator in the UK and is used at both the engineering offices and on station to support the analysis of refuelling events from two AGR stations, with a view to expanding it to the rest of the fleet in the near future
p-brane superalgebras via integrability
It has long been appreciated that superalgebras with bosonic and fermionic
generators additional to those in the super-Poincare algebra underlie p-brane
and D-brane actions in superstring theory. These algebras have been revealed
via "bottom up" approaches, involving consideration of Noether charges, and by
"top down" approaches, involving the construction of manifestly supersymmetry
invariant Wess-Zumino actions. In this paper, we give an alternative derivation
of these algebras based on integrability of supersymmetry transformations
assigned to fields in order to solve a cohomology problem related to the
construction of Wess-Zumino terms for p-brane and D-brane actions.Comment: 22 pages, typo corrected, reference adde
Learning models of plant behavior for anomaly detection and condition monitoring
Providing engineers and asset managers with a too] which can diagnose faults within transformers can greatly assist decision making on such issues as maintenance, performance and safety. However, the onus has always been on personnel to accurately decide how serious a problem is and how urgently maintenance is required. In dealing with the large volumes of data involved, it is possible that faults may not be noticed until serious damage has occurred. This paper proposes the integration of a newly developed anomaly detection technique with an existing diagnosis system. By learning a Hidden Markov Model of healthy transformer behavior, unexpected operation, such as when a fault develops, can be flagged for attention. Faults can then be diagnosed using the existing system and maintenance scheduled as required, all at a much earlier stage than would previously have been possible
Deriving all p-brane superalgebras via integrability
In previous work we demonstrated that the enlarged super-Poincare algebras
which underlie p-brane and D-brane actions in superstring theory can be
directly determined based on the integrability of supersymmetry transformations
assigned to fields appearing in Wess-Zumino terms. In that work we derived
p-brane superalgebras for p = 2 and 3. Here we extend our previous results and
give a compact expression for superalgebras for all valid p.Comment: 26 pages, table added, typos corrected, a few remarks added for
clarificatio
Data management of on-line partial discharge monitoring using wireless sensor nodes integrated with a multi-agent system
On-line partial discharge monitoring has been the subject of significant research in previous years but little work has been carried out with regard to the management of on-site data. To date, on-line partial discharge monitoring within a substation has only been concerned with single plant items, so the data management problem has been minimal. As the age of plant equipment increases, so does the need for condition monitoring to ensure maximum lifespan. This paper presents an approach to the management of partial discharge data through the use of embedded monitoring techniques running on wireless sensor nodes. This method is illustrated by a case study on partial discharge monitoring data from an ageing HVDC reactor
4 Technological Advancement and Long-Term Economic Growth in Asia
We are living in an age of remarkable technological change that is forcing us to think very hard about the linkages between technology and economic development. The harder we think about it,the more we realize that technological innovation i
Institutions and Geography: Comment on Acemoglu, Johnson and Robinson (2000)
This paper responds to findings by Acemoglu, Johnson and Robinson (2000) that suggest weak institutions, but not physical geography and correlates like disease burden, explain current variation in levels of economic development across former colonies. Using similar data and expanding the sample of countries analyzed, our regression analysis shows that both institutions and geographically-related variables such as malaria incidence or life expectancy at birth are strongly linked to gross national product per capita. We argue that the evidence presented in Acemoglu, Johnson and Robinson is likely limited by the inherently small sample of ex-colonies and the limited geographic dispersion of those countries.
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