3,589 research outputs found
GPS-guided mobile robot platform featuring modular design elements for agricultural applications : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Engineering in Mechatronics at Massey University Turitea Campus, Palmerston North, New Zealand
The agricultural industry has not seen significant innovation in development of low-cost automated farming solutions, with current systems costing several thousands of dollars to implement. Currently these automated solutions are primarily implemented around crop planting and harvesting, and the large implementation cost of these systems makes them unfeasible for small-scale operations. Within many agricultural industries, workers expend a considerable amount of time undertaking simple tasks that are labour intensive. Many of these tasks could instead be completed using a self-driving robotic platform outfitted with the appropriate devices required for the tasks.
This thesis covers the research work aiming to produce a solution that could turn an existing farming vehicle into a multipurpose low-cost agricultural platform, to act as the platform for an autonomous vehicle capable of performing pre-programmed tasks within an agricultural environment. A quad bike was selected as the vehicle platform for this research in which the control modules would control the speed and direction of this farm bike.
Four modules were developed to control the vehicle components that would normally be operated by a human operator. These modules are comprised of mechanical actuators coupled with a microcontroller control system and includes some specific designs to maintain the user's ability to manually control the pre-existing systems. A gear-changing module controls the vehicles manual gearbox, providing a method to detect and control the vehicles current gear. A speed control module was developed to control the vehicles throttle and braking system and detects the vehicles speed. A steering module controls the vehicles steering system, allowing for accurate control of the vehicles direction. Finally, a vehicle controller module provides a central command interface that ties the previous three modules together and controls the vehicles electrical components and engine.
Development of a low-cost differential GPS (DGPS) system was also undertaken to reduce the implementation cost of the system. Due to inconclusive results in relation to the positional accuracy of this system is was decided that a standard GPS system would be used for the vehicle prototype with further development on the DGPS system would be undertaken in future development of the research.
The successful development of a farm automated vehicle platform was achieved through this research. With further improvement on software, intelligent control and the development of a low-cost differential global positioning satellite (GPS) system, a fully autonomous farm platform that can be outfitted with different tools or devices for the required farm tasks is feasible and practical
New sensitivity of LHC measurements to composite dark matter models
We present sensitivity of LHC differential cross-section measurements to
so-called "stealth dark matter" scenarios occurring in an SU(N) dark gauge
group, where constituents are charged under the Standard Model and N=2 or 4.
The low-energy theory contains mesons which can be produced at the LHC, and a
scalar baryon dark matter (DM) candidate which cannot. We evaluate the impact
of LHC measurements on the dark meson masses. Using existing lattice results,
we then connect the LHC explorations to DM phenomenology, in particular
considering direct-detection experiments. We show that current LHC measurements
constrain DM masses in the region of 10 TeV. We discuss potential pathways to
explore these models further at the LHC
Picking the low-hanging fruit: testing new physics at scale with active learning
Since the discovery of the Higgs boson, testing the many possible extensions to the Standard Model has become a key challenge in particle physics. This paper discusses a new method for predicting the compatibility of new physics theories with existing experimental data from particle colliders. Using machine learning, the technique obtained comparable results to previous methods (>90% precision and recall) with only a fraction of their computing resources (<10%). This makes it possible to test models that were impossible to probe before, and allows for large-scale testing of new physics theories
New sensitivity of current LHC measurements to vector-like quarks
Quark partners with non-chiral couplings appear in several extensions of the
Standard Model. They may have non-trivial generational structure to their
couplings, and may be produced either in pairs via the strong and EM
interactions, or singly via the new couplings of the model. Their decays often
produce heavy quarks and gauge bosons, which will contribute to a variety of
already-measured "Standard Model" cross-sections at the LHC. We present a study
of the sensitivity of such published LHC measurements to vector-like quarks,
first comparing to limits already obtained from dedicated searches, and then
broadening to some so-far unstudied parameter regions
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Call to Action for Universities: Expanding the Public Health Approach for Child Abuse Prevention
Child abuse and neglect are significant issues facing our communities today that can lead to devastating consequences. Multiple risk factors can lead to instances of child maltreatment, including those related to the parents or guardians, the child, and the situational circumstances of families. In order to prevent child maltreatment, effective protective factors must be widely implemented and supported to mitigate the effects of possible risk factors. This strategy is supported by the public health approach to child maltreatment prevention. After communicating background research in these areas, this paper aims to explain why higher education organizations can contribute to this prevention effort and effect change on their campuses as well as in their communities
Phyllosphere microbiology with special reference to diversity and plant genotype
The phyllosphere represents the habitat provided by the aboveground parts of plants, and on a global scale supports a large and complex microbial community. Microbial interactions in the phyllosphere can affect the fitness of plants in natural communities, the productivity of agricultural crops, and the safety of horticultural produce for human consumption. The structure of phyllosphere communities reflects immigration, survival and growth of microbial colonists, which is influenced by numerous environmental factors in addition to leaf physico-chemical properties. The recent use of culture-independent techniques has demonstrated considerable previously unrecognized diversity in phyllosphere bacterial communities. Furthermore, there is significant recent evidence that plant genotype can play a major role in determining the structure of phyllosphere microbial communities. The main aims of this review are: (i) to discuss the diversity of phyllosphere microbial populations; (ii) to consider the processes by which microbes colonize the phyllosphere; (iii) to address the leaf characteristics and environmental factors that determine the survival and growth of colonists; (iv) to discuss microbial adaptations that allow establishment in the phyllosphere habitat and (v) to evaluate evidence for plant genotypic control of phyllosphere communities. Finally, we suggest approaches and priority areas for future research on phyllosphere microbiology
Testing new-physics models with global comparisons to collider measurements: the Contur toolkit
Measurements at particle collider experiments, even if primarily aimed at
understanding Standard Model processes, can have a high degree of model
independence, and implicitly contain information about potential contributions
from physics beyond the Standard Model. The Contur package allows users to
benefit from the hundreds of measurements preserved in the Rivet library to
test new models against the bank of LHC measurements to date. This method has
proven to be very effective in several recent publications from the Contur
team, but ultimately, for this approach to be successful, the authors believe
that the Contur tool needs to be accessible to the wider high energy physics
community. As such, this manual accompanies the first user-facing version:
Contur v2. It describes the design choices that have been made, as well as
detailing pitfalls and common issues to avoid. The authors hope that with the
help of this documentation, external groups will be able to run their own
Contur studies, for example when proposing a new model, or pitching a new
search
Interaction of amisulpride with GLUT1 at the blood-brain barrier. Relevance to Alzheimer’s disease
Blood-brain barrier (BBB) dysfunction may be involved in the increased sensitivity of Alzheimer's disease (AD) patients to antipsychotics, including amisulpride. Studies indicate that antipsychotics interact with facilitated glucose transporters (GLUT), including GLUT1, and that GLUT1 BBB expression decreases in AD. We tested the hypotheses that amisulpride (charge: +1) interacts with GLUT1, and that BBB transport of amisulpride is compromised in AD. GLUT1 substrates, GLUT1 inhibitors and GLUT-interacting antipsychotics were identified by literature review and their physicochemical characteristics summarised. Interactions between amisulpride and GLUT1 were studied using in silico approaches and the human cerebral endothelial cell line, hCMEC/D3. Brain distribution of [3H]amisulpride was determined using in situ perfusion in wild type (WT) and 5xFamilial AD (5xFAD) mice. With transmission electron microscopy (TEM) we investigated brain capillary degeneration in WT mice, 5xFAD mice and human samples. Western blots determined BBB transporter expression in mouse and human. Literature review revealed that, although D-glucose has no charge, charged molecules can interact with GLUT1. GLUT1 substrates are smaller (184.95±6.45g/mol) than inhibitors (325.50±14.40g/mol) and GLUT-interacting antipsychotics (369.38±16.04). Molecular docking showed beta-D-glucose (free energy binding: -15.39kcal/mol) and amisulpride (-29.04kcal/mol) interact with GLUT1. Amisulpride did not affect [14C]D-glucose hCMEC/D3 accumulation. [3H]amisulpride uptake into the brain (except supernatant) of 5xFAD mice compared to WT remained unchanged. TEM revealed brain capillary degeneration in human AD. There was no difference in GLUT1 or P-glycoprotein BBB expression between WT and 5xFAD mice. In contrast, caudate P-glycoprotein, but not GLUT1, expression was decreased in human AD capillaries versus controls. This study provides new details about the BBB transport of amisulpride, evidence that amisulpride interacts with GLUT1 and that BBB transporter expression is altered in AD. This suggests that antipsychotics could potentially exacerbate the cerebral hypometabolism in AD. Further research into the mechanism of amisulpride transport by GLUT1 is important for improving antipsychotics safety
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