Individualisation and Growing Diversity of Employment Relationships

At a time when the economic recession is more severe, and trade unions are weaker, than at any time since the War, it would be unproductive to speculate about the extent to which these changes have been imposed, acquiesced, or agreed by the workers concerned. Instead we focus on recent changes in employment relationships in Britain, and their consequences, and then on the winners and losers, which provides a cue for considering the longer term desirability of some of these developments for social justice and cohesion.Labour-management relations, individual and collective voice

Individualisation and growing diversity of employment relationships

At a time when the economic recession is more severe, and trade unions are weaker, than at any time since the War, it would be unproductive to speculate about the extent to which these changes have been imposed, acquiesced, or agreed by the workers concerned. Instead we focus on recent changes in employment relationships in Britain, and their consequences, and then on the winners and losers, which provides a cue for considering the longer term desirability of some of these developments for social justice and cohesion

Evaluating the relevance of the “Real Access” criteria as a framework for rural HCI research

Developing ICT software that is useful and usable in a rural context poses many problems. One of the major difficulties is understanding the real needs of the target users and the constraints imposed by the rural environment. Many techniques exist in the field of human computer interaction (HCI) that attempt to understand the needs of the target user but many are not useful in a rural context (or a least not when applied in a standard way). This paper presents some existing HCI research techniques that are applicable in a rural context and shows how they fit into the Bridges.org ‘Real Access’ framework.NRF, Telkom, Siemens, THRIP, IDRC, SANPADDepartment of HE and Training approved lis

The Equilateral Pentagon at Zero Angular Momentum: Maximal Rotation Through Optimal Deformation

A pentagon in the plane with fixed side-lengths has a two-dimensional shape space. Considering the pentagon as a mechanical system with point masses at the corners we answer the question of how much the pentagon can rotate with zero angular momentum. We show that the shape space of the equilateral pentagon has genus 4 and find a fundamental region by discrete symmetry reduction with respect to symmetry group D_5. The amount of rotation \Delta \theta for a loop in shape space at zero angular momentum is interpreted as a geometric phase and is obtained as an integral of a function B over the region of shape space enclosed by the loop. With a simple variational argument we determine locally optimal loops as the zero contours of the function B. The resulting shape change is represented as a Fourier series, and the global maximum of \Delta \theta \approx 45\degree is found for a loop around the regular pentagram. We also show that restricting allowed shapes to convex pentagons the optimal loop is the boundary of the convex region and gives \Delta \theta \approx 19\degree.Comment: 29 page

Reflection on three years of rural wireless Internet Protocol communication

This paper reports on three years of research and fieldwork with a rural wireless Internet Protocol communication project. We built a long-range WiFi network and custom communication software to support a rural telehealth project in the remote Eastern Cape. We report on our work using cellular networks, devices and applications as reference technologies because our users and beneficiaries are very comfortable with them. Of most concern are the technological and contextual issues affecting take up of the systems we designed. The paper intends to provide a summary analysis of our experience so that others in the field can learn from our successes and mistakes with respect to rural Information and Communication Technology for Development (ICT4D) in a South African context.Telkom, Cisco, THRIP, SANPAD, IDR

P6_7 Spider Silk

Spiders silk is often referred to as one of the most amazing materials in nature, with its exceptional strength, able to ensnare insects much greater in size and mass than that of the spider that spun the web. In this paper we explore the idea of using a single piece of spider silk to bring a moving car to a halt. We calculated that a Ford Focus moving at 50 mph could be stopped by a single 10 m long thread with a minimum diameter of 1.88 cm

Communicating in designing an oral repository for rural African villages

We describe designing an asynchronous, oral repository and sharing system that we intend to suit the needs and practices of rural residents in South Africa. We aim to enable users without access to personal computers to record, store, and share information within their Xhosa community using cellphones and a tablet PC combined with their existing face-to-face oral practices. Our approach recognises that systems are more likely to be effective if the design concept and process build on existing local communication practices as well as addressing local constraints, e.g. cost. Thus, we show how the objectives for the system emerged from prolonged research locally and how we communicated insights, situated in the community, into the process of design and development in a city-based lab. We discuss how we integrated understandings about communication between situated- and localresearchers and designers and developers and note the importance of recognising and centralising subtle differences in our perception of acts of oral communication. We go on to show how the materiality of the software, the tablet form factor, and touch interaction style played into our collaborative effort in conceiving the design.Department of HE and Training approved lis

The Dust Trail of Comet 67P/Churyumov-Gerasimenko between 2004 and 2006

We report on observations of the dust trail of comet 67P/Churyumov-Gerasimenko (CG) in visible light with the Wide Field Imager at the ESO/MPG 2.2m telescope at 4.7 AU before aphelion, and at 24 micron with the MIPS instrument on board the Spitzer Space Telescope at 5.7 AU both before and after aphelion. The comet did not appear to be active during our observations. Our images probe large dust grains emitted from the comet that have a radiation pressure parameter beta<0.01. We compare our observations with simulated images generated with a dynamical model of the cometary dust and constrain the emission speeds, size distribution, production rate and geometric albedo of the dust. We achieve the best fit to our data with a differential size distribution exponent of -4.1, and emission speeds for a beta=0.01 particle of 25 m/s at perihelion and 2 m/s at 3 AU. The dust production rate in our model is on the order of 1000 kg/s at perihelion and 1 kg/s at 3 AU, and we require a dust geometric albedo between 0.022 and 0.044. The production rates of large (>10 micron) particles required to reproduce the brightness of the trail are sufficient to also account for the coma brightness observed while the comet was inside 3 AU, and we infer that the cross-section in the coma of CG may be dominated by grains of the order of 60-600 micron.Comment: 79 pages, 13 figures, 6 tables. Accepted for publication in Icaru