2,182 research outputs found
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Unlocking the potential of community composting: Full project report
Community based composting schemes can make valuable contributions to the development of local infrastructure and amenities by improving soils and green spaces in addition to diverting waste from landfill. Furthermore, well managed community activities have potential for providing work and volunteering opportunities, as well as bringing people together and improving skills, knowledge and self-confidence. Considered collectively these factors may contribute to local sustainability more effectively than focusing on meeting particular waste related targets. Although there is some anecdotal and financial evidence for the growth in, and diversity of, community composting, there is very little comprehensive data that draws together the activity of the sector as a whole. This research set out to understand and assess the current and potential role of the community composting sector in achieving Defra’s waste related targets and Government’s other wider environmental and social objectives. Thus this research is timely both in terms of establishing what has been achieved in the community composting sector to-date and in terms of possibilities for future achievements
Nests, arcs and cycles in the lifespan of a studio project
Middlewood Sessions produced a kind of popular music that infuses the timbral aesthetics of jazz and orchestral music with the driving rhythms of dance music. This studio project, lasting for almost eight years, provided a rich resource for gaining insight into the increasingly prevalent context of the domestic project studio via a longitudinal case study approach. At the heart of this research is the desire to understand how people collaborate as part of a studio project, how people use technologies to make music and how all of this unfolds over time. To tackle the question of how to understand the shattered, scattered nature of creative practices, and in extending existing creativity research, I propose three ways of thinking about time: nests, arcs and cycles. While explicating this theoretical framework, something of the specific and idiographic nature of the case study, as an example of contemporary music production, is recounted
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Changing recycling behaviour: an evaluation of attitudes and behaviour to recycling in the Western Riverside area of London
Key to improving recycling performance in the UK is the need to more effectively engage the public and improve levels of participation. The research described in this paper combines quantitative and qualitative analysis of attitudinal and behavioural changes as part of an evaluation project to measure the impact of a multi-faceted waste awareness and education campaign in the Western Riverside Waste Authority area of central London. Analysis links attitudinal and behavioural responses to infrastructure provision and performance indicators for each area surveyed, as well as socio-demographic indicators. This paper presents the results and analysis of the attitudes, motivations and behaviours of a representative profile of households from this area of central London, in an attempt to better understand how behavioural change can be achieved and recycling targets met
A disturbance based control/structure design algorithm
Some authors take a classical approach to the simultaneous structure/control optimization by attempting to simultaneously minimize the weighted sum of the total mass and a quadratic form, subject to all of the structural and control constraints. Here, the optimization will be based on the dynamic response of a structure to an external unknown stochastic disturbance environment. Such a response to excitation approach is common to both the structural and control design phases, and hence represents a more natural control/structure optimization strategy than relying on artificial and vague control penalties. The design objective is to find the structure and controller of minimum mass such that all the prescribed constraints are satisfied. Two alternative solution algorithms are presented which have been applied to this problem. Each algorithm handles the optimization strategy and the imposition of the nonlinear constraints in a different manner. Two controller methodologies, and their effect on the solution algorithm, will be considered. These are full state feedback and direct output feedback, although the problem formulation is not restricted solely to these forms of controller. In fact, although full state feedback is a popular choice among researchers in this field (for reasons that will become apparent), its practical application is severely limited. The controller/structure interaction is inserted by the imposition of appropriate closed-loop constraints, such as closed-loop output response and control effort constraints. Numerical results will be obtained for a representative flexible structure model to illustrate the effectiveness of the solution algorithms
Active versus passive damping in large flexible structures
Optimal passive and active damping control can be considered in the context of a general control/structure optimization problem. Using a mean square output response approach, it is shown that the weight sensitivity of the active and passive controllers can be used to determine an optimal mix of active and passive elements in a flexible structure
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What makes people recycle? An evaluation of attitudes and behaviour in London Western Riverside
PlantID – DNA-based identification of multiple medicinal plants in complex mixtures
Background
An efficient method for the identification of medicinal plant products is now a priority as the global demand increases. This study aims to develop a DNA-based method for the identification and authentication of plant species that can be implemented in the industry to aid compliance with regulations, based upon the economically important Hypericum perforatum L. (St John’s Wort or Guan ye Lian Qiao).
Methods
The ITS regions of several Hypericum species were analysed to identify the most divergent regions and PCR primers were designed to anneal specifically to these regions in the different Hypericum species. Candidate primers were selected such that the amplicon produced by each species-specific reaction differed in size. The use of fluorescently labelled primers enabled these products to be resolved by capillary electrophoresis.
Results
Four closely related Hypericum species were detected simultaneously and independently in one reaction. Each species could be identified individually and in any combination. The introduction of three more closely related species to the test had no effect on the results. Highly processed commercial plant material was identified, despite the potential complications of DNA degradation in such samples.
Conclusion
This technique can detect the presence of an expected plant material and adulterant materials in one reaction. The method could be simply applied to other medicinal plants and their problem adulterants
QCD and QED dynamics of the EMC effect
Applying exact QCD sum rules for the baryon charge and energy-momentum we
demonstrate that if nucleons are the only degrees of freedom of nuclear wave
function, the structure function of a nucleus would be the additive sum of the
nucleon distributions at the same Bjorken x = AQ^2/2(p_Aq)< 0.5 up to very
small Fermi motion corrections if x>0.05. Thus the difference of the EMC ratio
from one reveals the presence of non-nucleonic degrees of freedom in nuclei.
Using exact QCD sum rules we show that the ratio R_A(x_p,Q^2) used in
experimental studies, where x_p = Q^2/2q_0 m_p deviates from one even if a
nucleus consists of nucleons with small momenta only. Use of the Bjorken x
leads to additional decrease of R_A(x,Q^2) as compared to the x_p plots.
Coherent contribution of equivalent photons into photon component of parton
wave function of a nucleus unambiguously follows from Lorentz transformation of
the rest frame nucleus Coulomb field. For A~200 photons carry ~0.0065 fraction
of the light momentum of nucleus almost compensates the difference between data
analysis in terms of Bjorken x and x_p. Different role of higher twist effects
for Q^2 probed at electron and muon beams is emphasized. Direct observations of
large and predominantly nucleonic short-range correlations in nuclei pose a
serious challenge for most of the models of the EMC effect for x>0.6. The data
are consistent with a scenario in which the hadronic EMC effect reflects
fluctuations of inter nucleon interaction due to fluctuations of color
distribution in the interacting nucleons. The dynamic realization of this
scenario is the model in which the 3q (3qg) configurations with x > 0.5 parton
have a weaker interaction with nearby nucleons, leading to suppression of such
configurations giving a right magnitude of the EMC effect. The directions for
the future studies and challenging questions are outlined.Comment: The sign in the relation of x_Bj and x_p is corrected and the
following discussion is adjusted accordingly. Discussion of the higher twist
effects is adde
On hypergeometric series reductions from integral representations, the Kampe de Feriet function, and elsewhere
Single variable hypergeometric functions pFq arise in connection with the
power series solution of the Schrodinger equation or in the summation of
perturbation expansions in quantum mechanics. For these applications, it is of
interest to obtain analytic expressions, and we present the reduction of a
number of cases of pFp and p+1F_p, mainly for p=2 and p=3. These and related
series have additional applications in quantum and statistical physics and
chemistry.Comment: 17 pages, no figure
A laboratory study to estimate pore geometric parameters of sandstones using complex conductivity and nuclear magnetic resonance for permeability prediction
We estimate parameters from the Katz and Thompson permeability model using laboratory complex electrical conductivity (CC) and nuclear magnetic resonance (NMR) data to build permeability models parameterized with geophysical measurements. We use the Katz and Thompson model based on the characteristic hydraulic length scale, determined from mercury injection capillary pressure estimates of pore throat size, and the intrinsic formation factor, determined from multi-salinity conductivity measurements, for this purpose. Two new permeability models are tested, one based on CC data and another that incorporates CC and NMR data. From measurements made on forty-five sandstone cores collected from fifteen different formations, we evaluate how well the CC relaxation time and the NMR transverse relaxation times compare to the characteristic hydraulic length scale and how well the formation factor estimated from CC parameters compares to the intrinsic formation factor. We find: (1) the NMR transverse relaxation time models the characteristic hydraulic length scale more accurately than the CC relaxation time (R2 of 0.69 and 0.39 and normalized root mean square errors (NRMSE) of 0.16 and 0.20, respectively); (2) the CC estimated formation factor is well correlated with the intrinsic formation factor (NRMSE=0.23). We demonstrate that that permeability estimates from the joint-NMR-CC model (NRMSE=0.13) compare favorably to estimates from the Katz and Thompson model (NRMSE=0.074). This model advances the capability of the Katz and Thompson model by employing parameters measureable in the field giving it the potential to more accurately estimate permeability using geophysical measurements than are currently possible
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