A framework for managing uncertain inputs: An axiomization of rewarding

The success postulate in belief revision ensures that new evidence (input) is always trusted. However, admitting uncertain input has been questioned by many researchers. Darwiche and Pearl argued that strengths of evidence should be introduced to determine the outcome of belief change, and provided a preliminary definition towards this thought. In this paper, we start with Darwiche and Pearl’s idea aiming to develop a framework that can capture the influence of the strengths of inputs with some rational assumptions. To achieve this, we first define epistemic states to represent beliefs attached with strength, and then present a set of postulates to describe the change process on epistemic states that is determined by the strengths of input and establish representation theorems to characterize these postulates. As a result, we obtain a unique rewarding operator which is proved to be a merging operator that is in line with many other works. We also investigate existing postulates on belief merging and compare them with our postulates. In addition, we show that from an epistemic state, a corresponding ordinal conditional function by Spohn can be derived and the result of combining two epistemic states is thus reduced to the result of combining two corresponding ordinal conditional functions proposed by Laverny and Lang. Furthermore, when reduced to the belief revision situation, we prove that our results induce all the Darwiche and Pearl’s postulates as well as the Recalcitrance postulate and the Independence postulate.

The Area Distribution of Solar Magnetic Bright Points

Magnetic bright points (MBPs) are among the smallest observable objects on the solar photosphere. A combination of G-band observations and numerical simulations is used to determine their area distribution. An automatic detection algorithm, employing one-dimensional intensity profiling, is utilized to identify these structures in the observed and simulated data sets. Both distributions peak at an area of approximate to 45,000 km(2), with a sharp decrease toward smaller areas. The distributions conform with log-normal statistics, which suggests that flux fragmentation dominates over flux convergence. Radiative magneto-convection simulations indicate an independence in the MBP area distribution for differing magnetic flux densities. The most commonly occurring bright point size corresponds to the typical width of inter-granular lanes.

Autopoiesis and the Home Confined Consumer: The Role of Personal Communities

Purpose – The purpose of this paper is to explore the consumption of a personal community and its role in the everyday life of the home-confined consumer. Design/methodology/approach – Using a Radical Constructivist approach, three cases of home confinement were explored in depth over a period of two years. Ongoing “conversations” captured the consumption experiences with personal communities. Findings – In relation to the home-confined context, the ability to attain individuality, empowerment and creativity are all heightened as a result of personal community construction. An underlying concern for home-confined consumers is their removal from independent living to institutionalized living, and, as a result the need to construct, manage and maintain a personal community is of major concern. Research limitations/implications – Although the study addresses a home-confined context, it is nevertheless reflective of concerns that are significant to all consumers, namely the attainment of individuality and independence irrespective of marginalization or not. Practical implications – The importance of a personal community in terms of both self-empowerment and self-identity with respect to marginalized groups and vulnerable individuals should not be underestimated. The supporting role of a personal community provides, in times of uncertainty, a framework to maintain self-identity and independence. Originality/value – This paper provides a better understanding of the role of a personal community in the consumption experiences of those consumers marginalized and vulnerable as a consequence of context. Home-confined consumers are “invisible” in the marketplace and the personal community is a means of redressing this imbalance by empowering such individuals.

Electrical energy storage and Smart Grid technologies to integrate the next generation of Renewable Power Systems

The growth of renewable power sources, distributed generation and the potential for alternative fuelled modes of transport such as electric vehicles has led to concerns over the ability of existing grid systems to facilitate such diverse portfolio mixes in already congested power systems. Internationally the growth in renewable energy sources is driven by government policy targets associated with the uncertainties of fossil fuel supplies, environmental issues and a move towards energy independence. Power grids were traditionally designed as vertically integrated centrally managed entities with fully dispatchable generating plant. Renewable power sources, distributed generation and alternative fuelled vehicles will place these power systems under additional stresses and strains due to their different operational characteristics. Energy storage and smart grid technologies are widely proposed as the tools to integrate these future diverse portfolio mixes within the more conventional power systems. The choice in these technologies is determined not only by their location on the grid system, but by the diversification in the power portfolio mix, the electricity market and the operational demands. This paper presents a high level technical and economic overview of the role and relevance of electrical energy storage and smart grid technologies in the next generation of renewable power systems.