Computational modelling of metal extrusion and forging processes

The computational modelling of extrusion and forging processes is now well established. There are two main approaches: Lagrangian and Eulerian. The first has considerable complexities associated with remeshing, especially when the code is parallelised. The second approach means that the mould has to be assumed to be entirely rigid and this may not be the case. In this paper, a novel approach is described which utilises finite volume methods on unstructured meshes. This approach involves the solution of free surface non-Newtonian fluid flow equations in an Eulerian context to track the behaviour of the workpiece and its extrusion/forging, and the solution of the solid mechanics equations in the Lagrangian context to predict the deformation/stress behaviour of the die. Test cases for modelling extrusion and forging problems using this approach will be presented.

A UK perspective on e-learning: an overview of the "workflow" and "reusable learning object" approach in the UK eUniversities project

The UK government started the UK eUniversities project in order to create a virtual campus for online education provisions, competing in a global market. The UKeU (WWW.ukeu.com) claims to "have created a new approach to e-learning" which "opens up a range of exciting opportunities for students, business and industry worldwide" to obtain both postgraduate and undergraduate qualifications. Although there has been many promises about the e-learning revolution using state-of-the-art multimedia technology, closer scrutiny of what is being delivered reveals that many of the e-learning models currently being used are little more than the old text based computer aided learning running on a global network. As part of the UKeU project a consortium of universities have been involved in developing a two year foundation degree from 2004. We look at the approach taken by the consortium in developing global e-learning provisions and the problems and the pitfalls that lay ahead.

Ontological considerations of time, meta-predicates and temporal propositions

A natural approach to representing and reasoning about temporal propositions (i.e., statements with time-dependent truth-values) is to associate them with time elements. In the literature, there are three choices regarding the primitive for the ontology of time: (1) instantaneous points, (2) durative intervals and (3) both points and intervals. Problems may arise when one conflates different views of temporal structure and questions whether some certain types of temporal propositions can be validly and meaningfully associated with different time elements. In this paper, we shall summarize an ontological glossary with respect to time elements, and diversify a wider range of meta-predicates for ascribing temporal propositions to time elements. Based on these, we shall also devise a versatile categorization of temporal propositions, which can subsume those representative categories proposed in the literature, including that of Vendler, of McDermott, of Allen, of Shoham, of Galton and of Terenziani and Torasso. It is demonstrated that the new categorization of propositions, together with the proposed range of meta-predicates, provides the expressive power for modeling some typical temporal terms/phenomena, such as starting-instant, stopping-instant, dividing-instant, instigation, termination and intermingling etc.

The Richit-Richards family of distributions and its use in forestry

Johnson's SB and the logit-logistic are four-parameter distribution models that may be obtained from the standard normal and logistic distributions by a four-parameter transformation. For relatively small data sets, such as diameter at breast height measurements obtained from typical sample plots, distribution models with four or less parameters have been found to be empirically adequate. However, in situations in which the distributions are complex, for example in mixed stands or when the stand has been thinned or when working with aggregated data, then distribution models with more shape parameters may prove to be necessary. By replacing the symmetric standard logistic distribution of the logit-logistic with a one-parameter “standard Richards” distribution and transforming by a five-parameter Richards function, we obtain a new six-parameter distribution model, the “Richit-Richards”. The Richit-Richards includes the “logit-Richards”, the “Richit-logistic”, and the logit-logistic as submodels. Maximum likelihood estimation is used to fit the model, and some problems in the maximum likelihood estimation of bounding parameters are discussed. An empirical case study of the Richit-Richards and its submodels is conducted on pooled diameter at breast height data from 107 sample plots of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.). It is found that the new models provide significantly better fits than the four-parameter logit-logistic for large data sets.

Flexible and robust run-time configuration for self-managing systems

This paper describes a methodology for deploying flexible dynamic configuration into embedded systems whilst preserving the reliability advantages of static systems. The methodology is based on the concept of decision points (DP) which are strategically placed to achieve fine-grained distribution of self-management logic to meet application-specific requirements. DP logic can be changed easily, and independently of the host component, enabling self-management behavior to be deferred beyond the point of system deployment. A transparent Dynamic Wrapper mechanism (DW) automatically detects and handles problems arising from the evaluation of self-management logic within each DP and ensures that the dynamic aspects of the system collapse down to statically defined default behavior to ensure safety and correctness despite failures. Dynamic context management contributes to flexibility, and removes the need for design-time binding of context providers and consumers, thus facilitating run-time composition and incremental component upgrade.

Coursework uploads and zero-tolerance deadlines

Clear assessment deadlines and severe penalties for late submission of coursework are a feature of a number of UK universities. This presents a severe challenge for any online upload system. Evidence from a range of different implementations at the School of Computing and Mathematical Sciences at the University of Greenwich over the past few years is examined to assess the impact of a zero-tolerance deadline policy on the way students work and the problems that arise. Suggestions are made on how to minimise any possible negative impact of a zero-tolerance deadline policy on the administration of the system and on staff and students.

Industrial water pollution in Dhaka, Bangladesh: strategies and incentives for pollution control in small and medium enterprises

The extent and gravity of the environmental degradation of the water resources in Dhaka due to untreated industrial waste is not fully recognised in international discourse. Pollution levels affect vast numbers, but the poor and the vulnerable are the worst affected. For example, rice productivity, the mainstay of poor farmers, in the Dhaka watershed has declined by 40% over a period of ten years. The study found significant correlations between water pollution and diseases such as jaundice, diarrhoea and skin problems. It was reported that the cost of treatment of one episode of skin disease could be as high as 29% of the weekly earnings of some of the poorest households. The dominant approach to deal with pollution in the SMEs is technocratic. Given the magnitude of the problem this paper argues that to control industrial pollution by SMEs and to enhance their compliance it is necessary to move from the technocratic approach to one which can also address the wider institutional and attitudinal issues. Underlying this shift is the need to adopt the appropriate methodology. The multi-stakeholder analysis enables an understanding of the actors, their influence, their capacity to participate in, or oppose change, and the existing and embedded incentive structures which allow them to pursue interests which are generally detrimental to environmental good. This enabled core and supporting strategies to be developed around three types of actors in industrial pollution, i.e., (i) principal actors, who directly contribute to industrial pollution; (ii) stakeholders who exacerbate the situation; and (iii) potential actors in mitigation. Within a carrot-and-stick framework, the strategies aim to improve environmental governance and transparency, set up a packet to incentive for industry and increase public awareness.

Ambitious mothers – successful daughters: Mothers’ early expectations for children’s education and children’s earnings and sense of control in adult life

Background. Mothers' expectations for their children's educational attainment are related to children's educational and occupational attainment. Studies have yet to establish, however, the long-term links between maternal expectations and offspring earnings, which are not always related to occupational attainment especially in women, or between maternal expectations and offspring sense of control and self-efficacy, which are pivotal factors in career choice and development. Aims. To explore the role of mothers' expectations for their children's educational attainment in children's earnings attainment and sense of control later in life. Method. Data from sweeps of the 1970 British Cohort Study (BCS70) were used. The study sample was those cohort members with complete information on all the variables of interest. The study sample (N = 3,285) was more educated and less disadvantaged than the whole sample. If cohort members of this type are more likely to have a mother who has high expectations, then our results are biased downwards, which suggests that we underestimate the effect of expectations on our two outcome variables. Results. Mothers' expectations at the age of 10 were positively related to daughters' sense of control at the age of 30 even after controlling for ethnicity, educational attainment, and concurrent partner, parent, and labour market participation status, as well as the following confounding variables (measured at the ages of 0–10): general ability and general ability squared, locus of control, emotional and behavioural problems and emotional and behavioural problems squared, socio-economic disadvantage, parental social class, parental family structure, and mothers' education, child-rearing attitudes, and mental health. Mothers' expectations had no effect on sons' adult outcomes. Conclusions. Given that women are particularly at risk for poor psychological and economic outcomes in adulthood, and that this study likely underestimated the effect of expectations on these two outcomes, this is an important conclusion.

Strategies for water pollution control in Dhaka, Bangladesh: an institutional and economic analysis

This paper presents primary data based on research carried out as part of a large World Bank project. Results from our survey show that water pollution in Dhaka watershed has reached alarming levels and is posing significant threats to health and economic activity, particularly among the poor and vulnerable. Rice productivity in the watershed area, for example, has declined by 40% in recent years and vegetable cultivation in the riverbeds has been severely damaged. We also found significant correlation between water pollution and diseases such as jaundice, diarrhoea and skin problems. It was reported that the cost of treatment of skin diseases for one episode could be as high as 29% of the weekly earnings of poor households. Given the magnitude of the contamination problem, a multi-agent stakeholder approach was necessary to analyse the institutional and economic constraints that would need to be addressed in order to improve environmental management. This approach, in turn, enabled core strategies to be developed. The strategies were better understood around three types of actors in industrial pollution, i.e. (1) principal actors, who contribute directly to industrial pollution; (2) stakeholders, who exacerbate the situation by inaction; and (3) the potential actors in mitigation of water contamination. Within a carrot-and-stick framework, nine strategies leading to the strengthening of environmental management were explored. They aim at improving governance and transparency within public agencies and private industry through the setting up of incentive structures to advance compliance and enforcement of environmental standards. Civil society and the population at large are, on the other hand, encouraged to contribute actively to the mitigation of water pollution by improving the management of environmental information and by raising public awareness.