314 research outputs found
Macroeconomic Impacts of Water Use in Agriculture
The recent/current recession provides the opportunity to study the effects of the macroeconomic changes on the agricultural production systems in the Great Plains and trace some of its impacts through the system to changes in primary inputs such water resource use. Therefore, the objective of the study reported here was to determine the effects of the changes in macroeconomic conditions driven by the 2008 recession on irrigated crop production in a portion of the Southern Great Plains and its impacts on water use. The approach for the study was to: (1) use the 10-year baseline FAPRI projections, based on changes in macroeconomic conditions, of agricultural commodity prices and input costs between the beginning of 2008 and the beginning of 2009, and (2) apply these different conditions within the Southern High Plains Ogallala Model (OM) in three counties representing different water situations and cropping patterns in the region. Overall results indicate that the 2008 recession likely had a relatively small impact on water use in the Southern Great Plains. Water use within the region is responsive to economic forces only when increased pumping flexibility exists; when water withdrawals are already at or near capacity, macroeconomic changes and changes in pumping costs and commodity prices are not likely to change water use.Ogallala Aquifer, recession, macroeconomic, Crop Production/Industries, Demand and Price Analysis, Environmental Economics and Policy, Land Economics/Use, Production Economics, Resource /Energy Economics and Policy, E00, Q15, Q30, Q31,
Filarial infection influences mosquito behaviour and fecundity
Understanding vector-parasite interactions is increasingly important as we move towards the endpoint goals set by the Global Programme for the Elimination of Lymphatic Filariasis (GPELF), as interaction dynamics may change with reduced transmission pressure. Elimination models used to predict programmatic endpoints include parameters for vector-specific transmission dynamics, despite the fact that our knowledge of the host-seeking behaviour of filariasis infected mosquitoes is lacking. We observed a dynamic, stage-specific and density dependent change in Aedes aegypti behaviour towards host cues when exposed to Brugia malayi filarial parasites. Infected mosquitoes exhibited reduced activation and flight towards a host during the period of larval development (L1/L2), transitioning to a 5 fold increase in activation and flight towards a host when infective stage larvae (L3) were present (p < 0.001). In uninfected control mosquitoes, we observed a reduction in convergence towards a host during the same period. Furthermore, this behaviour was density dependent with non-activated mosquitoes harbouring a greater burden of L1 and L2 larvae while activated mosquitoes harboured a greater number of L3 (p < 0.001). Reductions in fecundity were also density-dependent, and extended to mosquitoes that were exposed to microfilariae but did not support larval development
The Mechanical Psychologist: How Computational Techniques Can Aid Social Researchers in the Analysis of High-Stakes Conversation
Qualitative coding is an essential observational tool for describing behaviour in the social sciences. However, it traditionally relies on manual, time-consuming, and error-prone methods performed by humans. To overcome these issues, cross-disciplinary researchers are increasingly exploring computational methods such as Natural Language Processing (NLP) and Machine Learning (ML) to annotate behaviour automatically. Automated methods offer scalability, error reduction, and the discovery of increasingly subtle patterns in data compared to human effort alone (N. C. Chen et al., 2018). Despite promising advancements, concerns regarding generalisability, mistrust of automation, and value alignment between humans and machines persist (Friedberg et al., 2012; Grimmer et al., 2021; Jiang et al., 2021; R. Levitan & Hirschberg, 2011; Mills, 2019; Nenkova et al., 2008; Rahimi et al., 2017; Yarkoni et al., 2021).
This thesis investigates the potential of computational techniques, such as social signal processing, text mining, and machine learning, to streamline qualitative coding in the social sciences, focusing on two high-stakes conversational case studies. The first case study analyses political interviewing using a corpus of 691 interview transcripts from US news networks. Psychological behaviours associated with effective interviewing are measured and used to predict conversational quality through supervised machine learning. Feature engineering employs a Social Signal Processing (SSP) approach to extract latent behaviours from low-level social signals (Vinciarelli, Salamin, et al., 2009). Conversational quality, calculated from desired characteristics of interviewee speech, is validated by a human-rater study. The findings support the potential of computational approaches in qualitative coding while acknowledging challenges in interpreting low-level social signals.
The second case study investigates the ability of machines to learn expert-defined behaviours from human annotation, specifically in detecting predatory behaviour in known cases of online child grooming. In this section, the author utilises 623 chat logs obtained from a US-based online watchdog, with expert annotators labelling a subset of these chat logs to train a large language model. The goal was to investigate the machine’s ability to detect eleven predatory behaviours based on expert annotations. The results show that the machine could detect several behaviours with as few as fifty labelled instances, but rare behaviours were frequently over-predicted. The author next implemented a collaborative human-AI approach to investigate the trade-off between human accuracy and machine efficiency. The results suggested that a human-in-the-loop approach could improve human efficiency and machine accuracy, achieving near-human performance on several behaviours approximately fifteen times faster than human effort alone.
The conclusion emphasises the value of increased automation in social sciences while recognising the importance of social scientific expertise in cross-disciplinary re- search, especially when addressing real-world problems. It advocates for technology that augments and enhances human effort and expertise without replacing it entirely. This thesis acknowledges the challenges in interpreting computational signals and the importance of preserving human insight in qualitative coding. The thesis also highlights potential avenues for future research, such as refining computational methods for qualitative coding and exploring collaborative human-AI approaches to address the limitations of automated methods
DEMO: UAVs in crowd tagged mountain rescue
This project explores the potential for users to interact with live events in a new and dynamic way. It draws on fixed wing unmanned aircraft and associated sensor systems to provide realtime video and image data. It uses a web based software package as a crowd sourced imagery analysis tool allowing user involvement in the tagging and sorting of images. This technology allows a simulation of how the power of crowds[1] could be combined with Unmanned Aerial Vehicle (UAV) to monitor video footage and identify areas of particular interest by interacting with live video. A test flight in collaboration with Patterdale Mountain Rescue is used. The system fosters active citizenship by connecting communities to real life, live events in open-source creative communities. It explores the barriers and potential for an entirely new capacity for users to choose the perspective and proximity of their view by interacting with images from a UAV through ambient media. Copyright © 2013 ACM
Optimum size selection of CHP retrofitting in existing UK hotel building
Several studies have highlighted Combine Heat and Power (CHP) systems to be one of the proven and reliable technologies that can improve the efficiency of heat and electricity generation. The extensive adoption of this type of technology is crucial in reducing building emissions globally and in the U.K. This work uses a dynamic simulation software to evaluate the effect of CHP on the energy performance of an existing U.K. hotel and subsequently an approach to aid in the selection of optimum CHP size. The outcome of the study indicated that CHP systems in hotel buildings can provide considerable economic and environmental benefits with either maximally-sized CHP founded on the building’s base heat demand or with reduced CHP size of more than 50% smaller than the estimated maximum size. The optimum size design can be obtained through evaluation of the relationship between the main performance parameters and their variation with CHP sizes
Retrofit of a UK residential property to achieve nearly zero energy building standard
It is currently agreed upon that one of the major challenges in the construction industry is the energy efficiency of existing buildings. The World Meteorological Organisation (WMO) and United Nations (UN) have reported that the concentration of global atmospheric carbon dioxide has increased by an average of 50%, a record speed, from 2015 to 2016. The housing sector contributes to 45% of the UK’s carbon emissions. To help tackle some of those issues the recast Energy Performance Building Directive (EBPD) has introduced Nearly Zero Energy Buildings (NZEBs) in the coming years (including buildings that will undergo refurbishment/ renovations). This paper will explore the retrofitting of a UK residential dwelling using Thermal Analysis Simulation (TAS, EDSL) software by focusing on building fabric improvements and usage of on-site renewables. The CIBSE Test Reference Year (TRY) weather data has been selected to examine the performance of the building under current and future climate projections. The proposed design variables were finally implemented in the building altogether on TAS. The simulation results showed a reduction in the building’s annual energy consumption of 122.64kWh/m2 (90.24%). The greatest savings after this were achieved for the annual reduction in carbon emissions and avoided emissions, which were 84.59% and 816.47kg/CO2, respectively
Impact of window films on the overall energy consumption of existing UK hotel buildings
Recently, considerable attention has justifiably been directed towards energy savings in buildings as they account for up to 20–40% of total energy consumption in developed countries. In the United Kingdom, studies have revealed that buildings’ CO2 emissions for account for at least 43% of total emissions. Window panels are a major component of the building fabric with considerable influence on the façade energy performance and are accountable for up to 60% of a building’s overall energy loss. Therefore, the thermal performance of glazing materials is an important issue within the built environment. This work evaluates the impact of solar window films on the overall energy consumption of an existing commercial building via the use of a case study U.K. hotel and TAS dynamic simulation software. The study results demonstrated that the impact of window films on the overall energy consumption of the case study hotel is approximately 2%. However, an evaluation of various overall energy consumption components showed that the window films reduce the annual total cooling energy consumption by up to 35% along with a marginal 2% increase in the annual total heating energy consumption. They can also provide overall cost and CO2 emissions savings of up to 3%
An assessment of the benefits of yellow Sigatoka (Mycosphaerella musicola) control in the Queensland Northern Banana Pest Quarantine Area
The banana leaf spotting disease yellow Sigatoka is established and actively controlled in Australia through intensive chemical treatments and diseased leaf removal. In the State of Queensland, the State government imposes standards for de-leafing to minimise the risk of the disease spreading in 6 banana pest quarantine areas. Of these, the Northern Banana Pest Quarantine Area is the most significant in terms of banana production. Previous regulations imposed obligations on owners of banana plants within this area to remove leaves from plants with visible spotting on more than 15 per cent of any leaf during the wet season. Recently, this leaf disease threshold has been lowered to 5 per cent. In this paper we examine the likely impact this more-costly regulation will have on the spread of the disease. We estimate that the average net benefit of reducing the diseased leaf threshold is only likely to be $1.4 million per year over the next 30 years, expressed as the annualised present value of tightened regulation. This result varies substantially when the timeframe of the analysis is changed, with shorter time frames indicating poorer net returns from the change in protocols. Overall, the benefit of the regulation change is likely to be minor
Carbon emissions, and financial impacts from the incorporation of CHP and CCHP systems in existing UK hotel buildings
In recent years there has been an increasing interest in the incorporation of distributed energy resource (DER) systems such as combined heat and power (CHP) and combined cooling, heating, and power (CCHP) in commercial building applications as they have shown considerable environmental and financial benefits when compared to conventional energy generation. This paper aims to investigate the potential energy, carbon emissions, and financial impact of the size of co/tri-generation systems on a real case scenario of an existing UK hotel. The analysis is carried out using Thermal Analysis Simulation software (TAS) and a payback methodology is adopted to carry out the financial analysis. The results show that the average percentage decrease in carbon emissions with CHP is 32% and with CCHP it is 36%. Whilst both CHP and CCHP systems increase energy consumption in the building, the costs are reduced, and a CHP system contributes to a higher percentage of cost savings and shorter payback periods. The incorporation of a CCHP system leads to lower energy consumption for a similar-sized CHP system. Further simulations under future climate projections revealed that a CCHP system outperforms a CHP system
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