84,411 research outputs found
A high-level semiotic trust agent scoring model for collaborative virtual organisations
In this paper, we describe how a semiotic ladder, together with a supportive trust agent, can be used to address “soft” trust issues in the context of collaborative Virtual Organisations (VO). The intention is to offer all parties better support for trust (as reputation) management including the reduction of risk and improved reliability of VO e-services. The semiotic ladder is intended to support the VO e-service lifecycle through the articulation of e-trust at various levels of system abstraction, including trust as measurable confidence. At the social level, reputation and reliability measures of e-trust are the relevant dimensions as regards choice of VO partner and are also relevant to the negotiation of service level agreements between the VO partners. By contrast, at the lower levels of the trust ladder, e-trust measures typically address the degree to which secure sign on and message level security conforms to various tangible technological security protocols. The novel trust agent provides the e-service consumer with an objective measure of the trustworthiness of the e-service at run-time, just prior to its actual consumption. Specifically, VO e-service consumer confidence level is informed, by leveraging third party objective evidence. This evidence comprises a set of Corporate Governance (CG) scores. These scores are used as a trust proxy for the "real" owner of the VO. There are also inherent limitations associated with the use of CG scores. These are duly acknowledged
Secure Distributed Dynamic State Estimation in Wide-Area Smart Grids
Smart grid is a large complex network with a myriad of vulnerabilities,
usually operated in adversarial settings and regulated based on estimated
system states. In this study, we propose a novel highly secure distributed
dynamic state estimation mechanism for wide-area (multi-area) smart grids,
composed of geographically separated subregions, each supervised by a local
control center. We firstly propose a distributed state estimator assuming
regular system operation, that achieves near-optimal performance based on the
local Kalman filters and with the exchange of necessary information between
local centers. To enhance the security, we further propose to (i) protect the
network database and the network communication channels against attacks and
data manipulations via a blockchain (BC)-based system design, where the BC
operates on the peer-to-peer network of local centers, (ii) locally detect the
measurement anomalies in real-time to eliminate their effects on the state
estimation process, and (iii) detect misbehaving (hacked/faulty) local centers
in real-time via a distributed trust management scheme over the network. We
provide theoretical guarantees regarding the false alarm rates of the proposed
detection schemes, where the false alarms can be easily controlled. Numerical
studies illustrate that the proposed mechanism offers reliable state estimation
under regular system operation, timely and accurate detection of anomalies, and
good state recovery performance in case of anomalies
Purging of untrustworthy recommendations from a grid
In grid computing, trust has massive significance. There is lot of research
to propose various models in providing trusted resource sharing mechanisms. The
trust is a belief or perception that various researchers have tried to
correlate with some computational model. Trust on any entity can be direct or
indirect. Direct trust is the impact of either first impression over the entity
or acquired during some direct interaction. Indirect trust is the trust may be
due to either reputation gained or recommendations received from various
recommenders of a particular domain in a grid or any other domain outside that
grid or outside that grid itself. Unfortunately, malicious indirect trust leads
to the misuse of valuable resources of the grid. This paper proposes the
mechanism of identifying and purging the untrustworthy recommendations in the
grid environment. Through the obtained results, we show the way of purging of
untrustworthy entities.Comment: 8 pages, 4 figures, 1 table published by IJNGN journal; International
Journal of Next-Generation Networks (IJNGN) Vol.3, No.4, December 201
Using a Discrete Choice Experiment to Elicit Consumers’ WTP for Health Risk Reductions Achieved By Nanotechnology in the UK
We present research findings on consumers’ willingness to pay (WTP) for reductions in the level of foodborne health risks. The research addresses how such valuations are affected by the means of which the risk reduction is delivered and the methods of risk presentations used in choice tasks. In this case, the research has two treatments. In the first treatment, the comparison is between risk reductions achieved by an improvement in the food system in general (e.g., more stringent regulations and inspection regimes) within the slaughter and meat processing stages of the food chain, as opposed to a risk reduction achieved via innovations in food packaging using nanotechnology, which is the use of nanosensors in packaging. If there is a contamination in packaging, nanosensors reveal a colour change on the packaging material. In the second treatment, the comparison is between valuations of risk reductions in which reductions in risks are presented via absolute values and grids and absolute values together. Both comparisons are achieved via split sample Discrete Choice Experiment surveys. The difference between consumers’ valuations of foodborne risk reductions provides an implicit value for nanotechnology (i.e., WTP to avoid) and the effect of risk grids on choices people make. General results show the existence of heterogeneity in British consumers’ preferences. The effects of nanosensors and risk grids on consumers’ choices are not strong across the models. The valuations of health risk reductions show some variations across the models in both treatment groups.Discrete Choice Experiments, Nanotechnology, Nanosensors, Health Risks, Grids, UK, Health Economics and Policy,
Scenarios for the development of smart grids in the UK: literature review
Smart grids are expected to play a central role in any transition to a low-carbon energy future, and much research is currently underway on practically every area of smart grids. However, it is evident that even basic aspects such as theoretical and operational definitions, are yet to be agreed upon and be clearly defined. Some aspects (efficient management of supply, including intermittent supply, two-way communication between the producer and user of electricity, use of IT technology to respond to and manage demand, and ensuring safe and secure electricity distribution) are more commonly accepted than others (such as smart meters) in defining what comprises a smart grid.
It is clear that smart grid developments enjoy political and financial support both at UK and EU levels, and from the majority of related industries. The reasons for this vary and include the hope that smart grids will facilitate the achievement of carbon reduction targets, create new employment opportunities, and reduce costs relevant to energy generation (fewer power stations) and distribution (fewer losses and better stability). However, smart grid development depends on additional factors, beyond the energy industry. These relate to issues of public acceptability of relevant technologies and associated risks (e.g. data safety, privacy, cyber security), pricing, competition, and regulation; implying the involvement of a wide range of players such as the industry, regulators and consumers.
The above constitute a complex set of variables and actors, and interactions between them. In order to best explore ways of possible deployment of smart grids, the use of scenarios is most adequate, as they can incorporate several parameters and variables into a coherent storyline. Scenarios have been previously used in the context of smart grids, but have traditionally focused on factors such as economic growth or policy evolution. Important additional socio-technical aspects of smart grids emerge from the literature review in this report and therefore need to be incorporated in our scenarios. These can be grouped into four (interlinked) main categories: supply side aspects, demand side aspects, policy and regulation, and technical aspects.
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