Fluctuation spectrum of quasispherical membranes with force-dipole activity

The fluctuation spectrum of a quasi-spherical vesicle with active membrane proteins is calculated. The activity of the proteins is modeled as the proteins pushing on their surroundings giving rise to non-local force distributions. Both the contributions from the thermal fluctuations of the active protein densities and the temporal noise in the individual active force distributions of the proteins are taken into account. The noise in the individual force distributions is found to become significant at short wavelengths.Comment: 9 pages, 2 figures, minor changes and addition

The MTO-Framework for Implementation of E-Business Models

Venture capitalists typically require that you can explain the business model in the time it takes the lift to get to the tenth floor. Implementation typically takes years. There is a disproportionate large amount of focus on what constitutes an innovative new business model compared to implementation since most e-business failures are attributed to failures in implementation. Obviously, there is a significant lack of knowledge of factors leading to successful implementation among those responsible for practical implementation of e-business models. E-business models or IT-systems for inter-organizational purposes cannot be implemented exclusively following the traditional guidelines in the IS/IT literature. Development methods are very different from earlier, there are many more stakeholders, and the environment is much more dynamic. The paper suggests a framework highlighting important implementation factors derived from four different disciplines; venture capitalist experiences, business process reengineering, diffusion theory and system development. The contribution of the paper is a classification of implementation factors in a framework that identifies the technological, the organizational, and the market related factors relevant for implementation of e-business models

Breaking-down and parameterising wave energy converter costs using the CapEx and similitude methods

Wave energy converters (WECs) can play a significant role in the transition towards a more renewable-based energy mix as stable and unlimited energy resources. Financial analysis of these projects requires WECs cost and WEC capital expenditure (CapEx) information. However, (i) cost information is often limited due to confidentiality and (ii) the wave energy field lacks flexible methods for cost breakdown and parameterisation, whereas they are needed for rapid and optimised WEC configuration and worldwide site pairing. This study takes advantage of the information provided by Wavepiston to compare different costing methods. The work assesses the Froude-Law-similarities-based “Similitude method” for cost-scaling and introduces the more flexible and generic “CapEx method” divided into three steps: (1) distinguishing WEC’s elements from the wave energy farm (WEF)’s; (2) defining the parameters characterising the WECs, WEFs, and site locations; and (3) estimating elements that affect WEC and WEF elements’ cost and translate them into factors using the parameters defined in step (2). After validation from Wavepiston manual estimations, the CapEx method showed that the factors could represent up to 30% of the cost. The Similitude method provided slight cost-overestimations compared to the CapEx method for low WEC up-scaling, increasing exponentially with the scaling