SPDY vs HTTP/1.1: An Empirical Evaluation of Network Protocol Performance

As the Internet evolves, the reduction of page load time has an increased importance. Additionally, the application layer is an ideal place to change as it avoids altering existing implementations. HTTP was designed not realizing what the Internet would look like at the present, and is thus outdated. Google has developed a protocol as a replacement for HTTP called SPDY. The major improvements are header compression to avoid network congestion, multiplexing to maximize throughput, and allowing the server to suggest or even push unsolicited data. My research aims to measure throughput of the two protocols by varying both the latency and packet loss of a network

Local set approximation: Mattila-Vuorinen type sets, Reifenberg type sets, and tangent sets

We investigate the interplay between the local and asymptotic geometry of a set $A \subseteq \mathbb{R}^n$ and the geometry of model sets $\mathcal{S} \subset \mathcal{P}(\mathbb{R}^n)$, which approximate $A$ locally uniformly on small scales. The framework for local set approximation developed in this paper unifies and extends ideas of Jones, Mattila and Vuorinen, Reifenberg, and Preiss. We indicate several applications of this framework to variational problems that arise in geometric measure theory and partial differential equations. For instance, we show that the singular part of the support of an $(n-1)$-dimensional asymptotically optimally doubling measure in $\mathbb{R}^n$ ($n\geq 4$) has upper Minkowski dimension at most $n-4$.Comment: 52 pages, 5 figure

Applying forces to elastic network models of large biomolecules using a haptic feedback device

Elastic network models of biomolecules have proved to be relatively good at predicting global conformational changes particularly in large systems. Software that facilitates rapid and intuitive exploration of conformational change in elastic network models of large biomolecules in response to externally applied forces would therefore be of considerable use, particularly if the forces mimic those that arise in the interaction with a functional ligand. We have developed software that enables a user to apply forces to individual atoms of an elastic network model of a biomolecule through a haptic feedback device or a mouse. With a haptic feedback device the user feels the response to the applied force whilst seeing the biomolecule deform on the screen. Prior to the interactive session normal mode analysis is performed, or pre-calculated normal mode eigenvalues and eigenvectors are loaded. For large molecules this allows the memory and number of calculations to be reduced by employing the idea of the important subspace, a relatively small space of the first M lowest frequency normal mode eigenvectors within which a large proportion of the total fluctuation occurs. Using this approach it was possible to study GroEL on a standard PC as even though only 2.3% of the total number of eigenvectors could be used, they accounted for 50% of the total fluctuation. User testing has shown that the haptic version allows for much more rapid and intuitive exploration of the molecule than the mouse version

Mapping Transitions towards Sustainable Consumption : Latitudes, Legends and Declinations in the Interaction between Consumers Culture and Sustainable Business Models

This paper seeks to chart “a navigation route“ towards sustainable consumption. We draw on data collected in research on consumers’ response to integrated products and services bundles conceptualized in design literature as Product Service Systems (PSS). PSS is of interest as it offers potential social and environmental benefits. Such services- based sustainable consumption practices have been neglected by consumer researchers. Methodological approaches to sustainable consumption favoured by policy makers focus research and interventions on individual consumer behaviour, but these have very limited success. Consumer practices, and the role that Government and other institutions play, are a more appropriate conceptual framework to explicate sustainable consumption. However, this Practice Theory approach is not sufficient either; the best solution might be a combination of this with an understanding of the individual value pursued by consumers. We extend Shove (2010)’s contention that adoption of sustainable consumption practices can only be explained with socio-cultural approaches; we propose that a combination of this perspective with an understanding of the value expected by individual consumers, is a more suitable approach than either behavioural paradigms or practices on their own to map these adoption mechanisms.Non peer reviewe

What value do consumers really expect from Product Service Systems? : Reflections on how a different conception of value could facilitate the implementation of PSS in consumer markets

Purpose – This paper explores how PSS may create value in consumer markets in urban environment and how consumers value PSS beyond a narrow focus on functionality. Design/ methodology/approach – Within a case study of a use orientated PSS based on baby products, we conducted ten ethnographic interviews of current users of the scheme. Findings – Our data gives evidence that some of these products are important possessions for consumers’ identity construction. In contrast with highly visible products such as push-chairs, however, baby cots and car seats are seen by consumers from a more utilitarian perspective. Practical implications – The design of a PSS provision around products which are highly symbolic is problematic because of a need to fully understand the complex symbolism and hedonic value consumers attribute to these products. Originality /value – We fill a gap in PSS research by adopting a constructivist perspective to explore the multidimensional value consumers co-create around a baby products PSS.Non peer reviewedFinal Accepted Versio