1,646 research outputs found
Session:management of drainage near source – disconnection/minimise surface water entering public drainage
Many combined sewer networks are currently constrained due to lack of capacity. Surface water entering the network may have an impact on the local environment by causing additional spills from Combined Sewer Overflows (CSOs) and flooding events. With the increasing number of developments taking place in Scotland, more and more demands are being placed upon the existing wastewater assets and infrastructure of the drainage utility, Scottish Water. The principal way of preventing these CSO spills/flooding event s is to reduce the number of surface water connections to the combined sewer network and promote more surface water discharges to nearby watercourses.The problem is being addressed by examining all development applications as they are considered by a drainage planning officer in the water authority. The research reported in this paper is investigating the conditions under which it is reasonable and practical for Scottish Water to accept surface water flows into its combined sewer network . This paper presents a summary of the initial findings of the research to date by examining a sample of the sites examined. The objective of the work is to develop a methodology to support a rigorous stance on the acceptance of surface water flows into the combined sewer network. The results have not as yet been obtained
Any Time? Any Place? The impact on student learning of an on-line learning environment.
Original paper can be found at: http://www.actapress.com/Content_of_Proceeding.aspx?proceedingID=292#pages Copyright ACTA Press [Full text of this paper is not available in the UHRA]An increasing number of HE institutions are adopting virtual and managed learning environments (VLEs and MLEs), which offer flexible access to on-line learning materials all day and every day. There are multiple claims about e-learning enhancing learning and teaching (eg. [1] Britain and Liber, 1999; [2]Conole, 2002; [4]Allen, 2003; [5]Littlejohn and Higginson, 2003) such as supporting active learning, facilitative rather than didactic teaching and increased student motivation but these are not pre determined outcomes. Much depends on how lecturers use the available technology and how students respond to that use. This paper reports on a research project which has evaluated the students' own experience of on-line learning at the University of Hertfordshire. Using its own institution-wide MLE (StudyNet) academic staff at the university have been able to offer students on-line access to their study material from September 2001. Activities available for students using StudyNet include participating in discussion forums, using formative assessment materials and accessing journal articles as well as viewing and downloading courseware for each of their courses. Students were invited to participate in a questionnaire and focus groups to identify the characteristics of the on-line learning environment which benefited their learning
Thermal distortion analysis of the space station solar dynamic concentrator
A method was developed to evaluate the thermal distortion of the Space Station Solar Dynamic Concentrator and the effects of thermal distortion on concentrator optical performance. The analytical method includes generating temperature distributions with TRASYS and SINDA models, interfacing the SINDA results with the SINDA-NASTRAN Interface Program (SNIP), calculating thermal distortion with a NASTRAN/PATRAN finite element model, and providing flux distribution maps within the receiver with the ray tracing OFFSET program. Temperature distributions, thermally induced slope errors, and flux distribution maps within the receiver are discussed. Results during a typical orbit indicate that temperatures of the hexagonal panels and triangular facets range between -18 and 99 C (-1 to 210 F), facet rotations are less than 0.2 mrad, and a change in facet radius due to thermal flattening is less than 5 percent. The predicted power loss with thermal distortion effects was less than 0.3 percent. The thermal distortion of the Solar Dynamic concentrator has negligible effect on the flux distribution within the receiver cavity
Medium-term performance and maintenance of SUDS:a case-study of Hopwood Park Motorway Service Area, UK
One of the main barriers to implementing SUDS is concern about performance and maintenance costs since there are few well-documented case-studies. This paper summarizes studies conducted between 2000 and 2008 of the performance and maintenance of four SUDS management trains constructed in 1999 at the Hopwood Park Motorway Service Area, central England. Assessments were made of the wildlife value and sedimentation in the SUDS ponds, the hydraulic performance of the coach park management train, water quality in all management trains, and soil/sediment composition in the grass filter strip, interceptor and ponds. Maintenance procedures and costs were also reviewed. Results demonstrate the benefits of a management train approach over individual SUDS units for flow attenuation, water treatment, spillage containment and maintenance. Peak flows, pond sediment depth and contaminant concentrations in sediment and water decreased through the coach park management train. Of the 2007 annual landscape budget of £15,000 for the whole site, the maintenance costs for SUDS only accounted for £2,500 compared to £4,000 for conventional drainage structures. Furthermore, since sediment has been attenuated in the management trains, the cost of sediment removal after the recommended period of three years was only £554 and, if the design is not compromised, less frequent removal will be required in future
Advanced secondary power system for transport aircraft
A concept for an advanced aircraft power system was identified that uses 20-kHz, 440-V, sin-wave power distribution. This system was integrated with an electrically powered flight control system and with other aircraft systems requiring secondary power. The resulting all-electric secondary power configuration reduced the empty weight of a modern 200-passenger, twin-engine transport by 10 percent and the mission fuel by 9 percent
Clonal expansion within pneumococcal serotype 6C after use of seven-valent vaccine
Streptococcus pneumoniae causes invasive infections, primarily at the extremes of life. A seven-valent conjugate vaccine (PCV7) is used to protect against invasive pneumococcal disease in children. Within three years of PCV7 introduction, we observed a fourfold increase in serotype 6C carriage, predominantly due to a single clone. We determined the whole-genome sequences of nineteen S. pneumoniae serotype 6C isolates, from both carriage (n = 15) and disease (n = 4) states, to investigate the emergence of serotype 6C in our population, focusing on a single multi-locus sequence type (MLST) clonal complex 395 (CC395). A phylogenetic network was constructed to identify different lineages, followed by analysis of variability in gene sets and sequences. Serotype 6C isolates from this single geographical site fell into four broad phylogenetically distinct lineages. Variation was seen in the 6C capsular locus and in sequences of genes encoding surface proteins. The largest clonal complex was characterised by the presence of lantibiotic synthesis locus. In our population, the 6C capsular locus has been introduced into multiple lineages by independent capsular switching events. However, rapid clonal expansion has occurred within a single MLST clonal complex. Worryingly, plasticity exists within current and potential vaccine-associated loci, a consideration for future vaccine use, target selection and design
Theory of Networked Minority Games based on Strategy Pattern Dynamics
We formulate a theory of agent-based models in which agents compete to be in
a winning group. The agents may be part of a network or not, and the winning
group may be a minority group or not. The novel feature of the present
formalism is its focus on the dynamical pattern of strategy rankings, and its
careful treatment of the strategy ties which arise during the system's temporal
evolution. We apply it to the Minority Game (MG) with connected populations.
Expressions for the mean success rate among the agents and for the mean success
rate for agents with neighbors are derived. We also use the theory to
estimate the value of connectivity above which the Binary-Agent-Resource
system with high resource level goes into the high-connectivity state.Comment: 24 pages, 3 figures, submitted to PR
Predictability of large future changes in a competitive evolving population
The dynamical evolution of many economic, sociological, biological and
physical systems tends to be dominated by a relatively small number of
unexpected, large changes (`extreme events'). We study the large, internal
changes produced in a generic multi-agent population competing for a limited
resource, and find that the level of predictability actually increases prior to
a large change. These large changes hence arise as a predictable consequence of
information encoded in the system's global state.Comment: 10 pages, 3 figure
Years of life lost (YLL) from cancer is an important measure of population burden – and should be considered when allocating research funds
Recently, cancer mortality has been compared to research spending by the National Cancer Research Institute (NCRI), whose research budget is approximately £250 million. The analysis shows a mis-match between mortality and research spending. As well as crude mortality rates, other measures of cancer burden should be considered because they contribute additional information. ‘Years of life lost' (YLL) summed over each individual dying after a diagnosis of cancer represents a population-based mortality indicator of the impact of that disease on society. Years of life lost divided by the number of deaths for each cancer site produces an additional statistic, the average years of life lost (AYLL), which is a measure of the burden of cancer to the individual patient. For 17 cancer sites where data are available, four tumour sites have a rather large difference in mortality, comparing YLL to crude mortality. Years of life lost shows the population burden from cancers of the ovary, cervix, and CNS to be rather larger than suggested by crude mortality, despite screening programmes for cervix cancer. Using YLL, the underprovision of funding for lung cancer research is similar to that reported using percentage mortality. Breast cancer and leukaemia receive a relatively higher research spend than the population burden of these cancers, and the spending on leukaemia is quite extreme. Prostate cancer has a low per cent YLL but attracts a moderate amount of research spending. The use of AYLL as an indicator of individual cancer burden considerably changes the ranking of the mortality from different tumours. The mean AYLL is 12.5 years. Prostate cancer has the lowest AYLL, only 6.1 years; brain tumour patients have the highest, at just over 20 years. Comparing AYLL to research spending suggests four ‘Cinderella' cancer sites with high individual cancer burden but low research spending: CNS tumours, cervix and kidney cancers, and melanoma. Breast cancer and leukaemia have roughly average AYLL but a considerable excess of research spending. YLL emphasises the discrepancy between research spending and mortality, and may be helpful for decisions concerning research support. Avearage years of life lost measures the burden to individual patients and may be helpful where individuals' needs are relevant, such as palliative care. As well as crude mortality, more subtle and comprehensive calculations of mortality statistics would be useful in debates on research funding and public health issues
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