89,118 research outputs found
A participatory methodology for large scale field trials in the UK
Farmer participation was essential in developing a uniquely useful set of wheat variety trials data on a wide range of organic farms over two years. Although the trials were successful, it became clear that some of the participating farmers felt there were some limitations in the process. These included a lack of ownership in the project and a concern for more researcher help. It was clear that a greater time in-vestment was needed at the start of the project to help with farmer understanding and ownership. De-spite the negative comments, farmers appreciated their involvement, particularly in contrasting their own views and information with that from the wider scene. Farmer participation is essential for systems-level research and this project helped to develop a small core of trained farmers and researchers
SUSTAINABILITY OF POULTRY PRODUCTION USING THE EMERGY APPROACH: COMPARISON OF CONVENTIONAL AND ORGANIC REARING SYSTEMS
The organic production system is an important strategy, compatible with sustainable agriculture, avoiding the use of chemical compounds,limiting the intensity of production and providing controls along the entire chain of production. The aim of this study is to compare conventional and organic poultry production in terms of emergy analysis. The main differences in the two systems were the emergy cost for poultry feed and for cleaning/sanitization of the buildings between successive productive cycles. In both production systems the poultry feed represented more than 50% of the emergy flow. Regarding the agronomic phase, it was shown that almost all the organic crops, avoiding
chemical fertilizers and pesticides, saved around 60% emergy. The emergetic costs for housing of the birds were very similar in both systems. Relating the emergy results with productive performance it is possible to show that, although the annual productive performance was much lower in organic than in conventional (206%), transformity of organic poultry was around 10% lower. Comparison of the organic poultry system with a conventional one from the viewpoint of sustainability showed that all the emergy-based indicators are in favour of the organic farming system with a higher efficiency in transforming the available inputs in the final product, a higher level of renewable inputs, a higher level of local inputs and a lower density of energy and matter flows
Effect of wheat production system components on food preference in rats
In the study presented the effects of two major system components - fertility management and crop protection - were tested in a rat preference test for the first time. Wheat samples produced under 4 combinations of these management factors: -a) organic fertility and crop protection management, b) organic fertility management and conventional crop protection c) conventional fertility management and organic crop protection and d) conventional fertility management and crop protection - generated in the Nafferton factorial systems comparison (NFSC) trial at Newcastle University, were used as experimental diets. Results showed that the organically fertilised wheat was preferred by rats (P = 0.001) while the organic crop protection resulted in reduced wheat consumption (not significant). This might indicate that the rats did not sense or did not select against possible traces of plant protection agents but responded more clearly to differences that were caused by the fertility management
Model Prediction-Based Approach to Fault Tolerant Control with Applications
Abstract— Fault-tolerant control (FTC) is an integral component in industrial processes as it enables the system to continue robust operation under some conditions. In this paper, an FTC scheme is proposed for interconnected systems within an integrated design framework to yield a timely monitoring and detection of fault and reconfiguring the controller according to those faults. The unscented Kalman filter (UKF)-based fault detection and diagnosis system is initially run on the main plant and parameter estimation is being done for the local faults. This critical information\ud
is shared through information fusion to the main system where the whole system is being decentralized using the overlapping decomposition technique. Using this parameter estimates of decentralized subsystems, a model predictive control (MPC) adjusts its parameters according to the\ud
fault scenarios thereby striving to maintain the stability of the system. Experimental results on interconnected continuous time stirred tank reactors (CSTR) with recycle and quadruple tank system indicate that the proposed method is capable to correctly identify various faults, and then controlling the system under some conditions
Bibliographic Review on Distributed Kalman Filtering
In recent years, a compelling need has arisen to understand the effects of distributed information structures on estimation and filtering. In this paper, a bibliographical review on distributed Kalman filtering (DKF) is provided.\ud
The paper contains a classification of different approaches and methods involved to DKF. The applications of DKF are also discussed and explained separately. A comparison of different approaches is briefly carried out. Focuses on the contemporary research are also addressed with emphasis on the practical applications of the techniques. An exhaustive list of publications, linked directly or indirectly to DKF in the open literature, is compiled to provide an overall picture of different developing aspects of this area
A participatory approach to variety trials for organic systems
A participatory research methodology was used to compare the performance of UK wheat varieties under organic conditions. Plots of three breadmaking winter wheat varieties (Hereward, Solstice and Xi19) and a mixture (1:1:1) of the varieties were grown at 19 UK farms in two seasons (2003/04 and 2004/05). Meas-urements were taken of growth habit, yield and grain quality. Grain yields in both seasons showed significant site by variety interactions, although the variation among sites was greater than among varieties in both instances. Wheat grown at Western sites was significantly shorter and higher-yielding than that grown at Eastern sites in 2003/04 but significantly taller in 2004/05. As with grain yield, greater variation among site than variety was found in the Hagberg Falling Number and protein concentra-tion results in both seasons. The results from the two years of trials illustrate the variability of organic systems and the difficulty in selecting a single variety suitable for organic farms
The human fear-circuitry and fear-induced fainting in healthy individuals The paleolithic-threat hypothesis
The Paleolithic-Threat
hypothesis reviewed here posits
that habitual efferent fainting can
be traced back to fear-induced
allelic polymorphisms that were
selected into some genomes of
anatomically, mitochondrially, and
neurally modern humans (Homo
sapiens sapiens) in the Mid-Paleolithic because of the survival
advantage they conferred during
periods of inescapable threat. We
posit that during Mid-Paleolithic
warfare an encounter with “a
stranger holding a sharp object”
was consistently associated with
threat to life. A heritable hard-
wired or firm-wired (prepotentiated) predisposition to abruptly
increase vagal tone and collapse
flaccidly rather than freeze or
attempt to flee or fight in response
to an approaching sharp object, a
minor injury, or the sight of blood,
polymorphism for the hemodynamically “paradoxical” flaccid-
immobility in response to these
stimuli may have increased some
non-combatants’ chances of survival. This is consistent with the
unusual age and sex pattern of
fear-induced fainting. The Paleolithic-Threat hypothesis also predicts a link to various hypo-androgenic states (e.g. low dehydroxyepiandrosterone-sulfate. We offer
five predictions testable via epidemiological, clinical, and ethological/primatological methods. The
Paleolithic-Threat hypothesis has
implications for research in the
aftermath of man-made disasters,
such as terrorism against civilians,
a traumatic event in which this
hypothesis predicts epidemics of
fear-induced faintin
Implications of the Information Technology Revolution for People with Disabilities
The paper focuses on opportunities for the integration of persons with different types of disabilities in the information technology (IT) labour market. Recent IT developments are identified and examined for their potentially harmful or beneficial effects on access to the IT labour market for persons with disabilities. The opportunities created by new job creation, new forms of training, teleworking, and the role of assistive technologies in facilitating workplace accommodations are briefly described. The focus is on new options for the design and implementation of computer-related assistive technologies in the workplace, and the impact of teleworking and the World Wide Web on employability and work-related training of persons with disabilities. The paper closes with a brief discussion of the roles that government agencies, business firms, labour unions, non-governmental organisations and education can play to help people with disabilities join the IT revolution and share its benefits
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