334 research outputs found
Wasted food, wasted energy: The embedded energy in food waste in the United States
No full textThis work estimates the energy embedded in wasted food
annually in the United States. We calculated the energy intensity
of food production from agriculture, transportation, processing,
food sales, storage, and preparation for 2007 as 8080 +- 760
trillion BTU. In 1995 approximately 27% of edible food was wasted.
Synthesizing these food loss figures with our estimate of
energy consumption for different food categories and food
production steps, while normalizing for different production
volumes, shows that 2030 +- 160 trillion BTU of energy were
embedded in wasted food in 2007. The energy embedded in
wasted food represents approximately 2% of annual energy
consumption in the United States, which is substantial when
compared to other energy conservation and production proposals.
To improve this analysis, nationwide estimates of food waste
and an updated estimate for the energy required to produce food
for U.S. consumption would be valuable.Mechanical Engineerin
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Cow power: The energy and emissions benefits of converting manure to biogas
No full textThis report consists of a top-level aggregate analysis of the total potential for converting
livestock manure into a domestic renewable fuel source (biogas) that could be used to help
states meet renewable portfolio standard requirements and reduce greenhouse gas (GHG)
emissions. In the US, livestock agriculture produces over one billion tons of manure annually
on a renewable basis. Most of this manure is disposed of in lagoons or stored outdoors to
decompose. Such disposal methods emit methane and nitrous oxide, two important GHGs with
21 and 310 times the global warming potential of carbon dioxide, respectively. In total, GHG
emissions from the agricultural sector in the US amounted to 536 million metric tons (MMT) of
carbon dioxide equivalent, or 7% of the total US emissions in 2005. Of this agricultural
contribution, 51 to 118 MMT of carbon dioxide equivalent resulted from livestock manure
emissions alone, with trends showing this contribution increasing from 1990 to 2005. Thus,
limiting GHG emissions from manure represents a valuable starting point for mitigating
agricultural contributions to global climate change.
Anaerobic digestion, a process that converts manure to methane-rich biogas, can lower
GHG emissions from manure significantly. Using biogas as a substitute for other fossil fuels,
such as coal for electricity generation, replaces two GHG sources—manure and coal
combustion—with a less carbon-intensive source, namely biogas combustion.
The biogas energy potential was calculated using values for the amount of biogas energy
that can be produced per animal unit (defined as 1000 pounds of animal) per day and the
number of animal units in the US. The 95 million animal units in the country could produce
nearly 1 quad of renewable energy per year, amounting to approximately 1% of the US total
energy consumption. Converting the biogas into electricity using standard microturbines could
produce 88 ± 20 billion kWh, or 2.4 ± 0.6% of annual electricity consumption in the US.
Replacing coal and manure GHG emissions with the emissions from biogas would produce a
net potential GHG emissions reduction of 99 ± 59 million metric tons or 3.9 ± 2.3% of the
annual GHG emissions from electricity generation in the US.Mechanical Engineerin
Savage values: Conservation and personhood in southern Suriname
No full textThe idea of indigenous peoples of Amazonia living in harmony with their environment may be a cliché, with origins in romantic portrayals of native Americans such as those of Hudson, Rousseau or Chateaubriand, but recent studies in anthropology and ecology have confirmed that indigenous Amazonian ways of life are materially ‘sustainable’, given the right circumstances (Shepard et al. 2012), although they are not necessarily maintained on the basis of ideologies of sustainability. Nor are they based on ideas of harmony or equilibrium; indeed, students of Amerindian thought have found it characterized on the contrary by a tendency towards ‘perpetual disequilibrium’ (Lévi-Strauss 1991: 316). Change, but also social reproduction, may be regarded as being due to the fact that the elements of the whole are in disequilibrium, even when their immediate relationships towards each other appear stable. In this chapter I shall try to explore the implications of these features of native Amazonian society and ecology for ideas about human-wildlife conflict. I shall begin with some reflections about the distinction between nature and culture heavily implicit in the ‘human- wildlife’ relationship. I shall then consider what it means to be ‘human’ and to be ‘animal’ in native Amazonian societies. This will bring me to the specific case of the Trio, who have become involved first with Christianity and then with conservation organizations. I shall argue that the notion of human-wildlife conflict is implicit in the conservation agenda, but depends on a worldview that derives from Christianity. Yet the Trio’s engagement with conservation and the human-wildlife conflict paradigm is based on their own agenda, not one prescribed by outsiders
LitCrit: exploring intentions as a basis for automated feedback on Related Work.
No full textLearning the skill of academic writing is critical for post-graduate (PG) students to
be successful, yet many struggle to master the required standard. Feedback can play a formative role in developing these skills, but many students do not find sufficiently helpful the kinds of feedback available to them. As the Related Work section is known to be particularly difficult for PG students to master that is the focus of this thesis.
To date, models of academic writing have been built on observational studies of
academic articles. In contrast, we carry out a user study to explore what content experts look for in Related Work and how this differs from PG students. We claim that by understanding what experts look for in Related Work and what aspects PG students struggle with, a useful author intention model can be developed to support writing feedback for Related Work sections. Our work demonstrates reliable annotation of the model intentions. Developing on existing algorithms, designed to identify rhetorical intentions in academic writing, we build a supervised machine learning classifier, showing how features focused on Related Work sections improve recognition of content aspects. Carrying out a study to rate the quality of Related Work, we demonstrate that the model is a good proxy for predicting quality, validating the choice of intentions in our model. In addition to recognising author intentions, we automate the generation of feedback based on observations of intentions that are present and missing, taking into account areas that PG students struggle to recognise.
The thesis also contributes a new prototype writing analytic tool, called LitCrit,
that supports visualising the intention narrative of Related Work and presents feedback. We claim this visualisation approach changes the PG student’s perception of Related Work, and demonstrate through a user study that it does draw attention to aspects previously missed bringing PG student responses in line with experts. Finally, we explore the performance of our classifier, originally set within the Computational Linguistics discipline, to that of Computer Graphics. This shows us that while performance may be lower when care is taken to understand those features which are discipline dependent, there is scope for improvement. Also, while a discipline may have the same intentions present in a section, their structural presentation may differ impacting feature choice
Map showing the location of the four study areas in relation to Budongo Forest Reserve (inset Uganda country map).
No full text<p>Adapted from Webber et al. 2007 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0102912#pone.0102912-Webber3" target="_blank">[63]</a>.</p
Local and regional greenhouse gas management
No full textThe paper is the result of 20 years of research in Leicester and other cities quantifying the energy related greenhouse gas emissions. The work informed Leicester City Council's climate change policies, including the Climate Change Strategy of 2003, which was co-authored by Fleming.
Webber now works at Leicester City Council and is responsible for monitoring the Council's greenhouse gas emissions. Fleming is a member of the City Council’s Environment Scrutiny Advisory Panel and also a member of the East Midlands Regional Assembly Energy Scrutiny Panel. These panels are reviewing the progress of Leicester City Council and the East Midlands Development Agency in reducing greenhouse gas emissions based on the approach recommended in the paper.
Webber was a PhD student in the IESD, supervised by Fleming who was the lead author
Voice Compression and Communications: Principles and Applications for Fixes and Wireless Channels
No full textUp-to-date, expert coverage of topics in wireless voice communications Voice communication is the most important facet of mobile radio service. Even when the predicted surge of wireless data and Internet services becomes a reality, voice will remain the most natural means of human communication. Voice Compression and Communications details issues in wireless voice communications and treats compression, channel coding, and wireless transmission as a joint subject. Part I covers background material, whereas Part II provides detailed information on both proprietary and standardized analysis-by-synthesis codecs, including the speech codecs of virtually all existing wireline-based and wireless systems. Parts III and IV discuss mainly research-based wideband, audio, as well as very low-rate schemes likely to find their way into future standards. Voice Compression and Communications describes fundamental concepts in a non-mathematical way early in the book for those with only a background knowledge of signal processing and communications. More advanced readers will find detailed discussions of theoretical principles, future concepts, and solutions to various specific wireless voice communications problems
Primate crop raiding in Uganda : actual and perceived risks around Budongo Forest reserve
No full textCrop damage by wildlife is a significant threat to global conservation and human development. This interdisciplinary study compared the actual and perceived risk of primate crop raiding around Budongo Forest Reserve, northwest Uganda during 2004/2005. Weekly farm monitoring established that at least seven wild species damage crops, and primates (primarily baboons) are responsible for forty percent of all raids. The creation of risk maps using GIS technology and logistic regression revealed that those cultivating maize close to the forest edge are particularly vulnerable to loss. An elevated level of human presence was found to significantly reduce raids by wild species although it is not considered effective due to the high social cost. Overall the majority of farmers experience little damage by wildlife and many other factors limit agricultural production e.g. insects, weather and domestic livestock; goats raid more frequently than any other animal and their pruning of maize was proven to significantly reduce yield. Despite the low risk of actual loss, semi-structured interviews, focus groups and pm1icipant observation revealed that crop raiding by wild species is believed to be the most significant limitation to livelihoods in this area. Damage intensity, fluctuations in social condition and restrictions on traditional crop protection methods all inflate perceptions of risk. Crop damage by wildlife also symbolizes control by external forces; the forest is believed to be 'owned' by the same organizations that impose conservation legislation and restrict access to resources. Raiding species, and primates in particular, are judged alongside human moral values and local people are more tolerant of animals they believe they can control or that have associated benefits i.e. domestic and game species.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Measurement of the D+/- production asymmetry in 7 TeV pp collisions
No full textThe asymmetry in the production cross-section \sigma of D+/- mesons, A_P = (\sigma(D+) - \sigma(D-))/(\sigma(D+) + \sigma(D-)), is measured in bins of pseudorapidity \eta and transverse momentum p_T within the acceptance of the LHCb detector. The result is obtained with a sample of D+ -> K_S pi+ decays corresponding to an integrated luminosity of 1.0 fb^-1, collected in pp collisions at a centre of mass energy of 7 TeV at the Large Hadron Collider. When integrated over the kinematic range 2.0 K_S pi+ decay is negligible. No significant dependence on \eta or p_T is observed
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