Calculating the fluxes of atmospheric neutrinos

The study of neutrinos produced in the interaction of cosmic rays with atmospheric nuclei was instrumental to the discovery of neutrino oscillations. As neutrino physics now enters the precision measurement era, precise measurement of atmospheric neutrino oscillations remains of interest due to its ability to answer questions such as the extent of CP violation in the neutrino sector and the ordering of the neutrino masses. An analysis of neutrino oscillations involves a comparison between the neutrino flux measured by a detector such as the Super-Kamiokande detector in Japan and the neutrino flux expected in the absence of oscillations. This thesis presents an estimate for the un-oscillated atmospheric neutrino flux using the Bartol atmospheric Monte Carlo simulation. The previous iteration of the Bartol flux estimate released in 2004 found that the dominant sources of systematic uncertainty on the neutrino flux were the uncertainty of the flux of cosmic rays and uncertainties in hadron production during the interaction of those cosmic rays with the atmosphere. Within this thesis, measurements of hadron production by fixed target experiments are used to develop a dataset- driven model which is applied to the simulation of pion and kaon production in atmospheric showers. The significant fraction of the relevant hadron production phase space covered by the datasets released since 2004 allows, for the first time, a calculation of the neutrino flux with hadronic interactions predominantly based on dataset measurements rather than Monte Carlo prediction. Additionally, an updated parameterisation of the cosmic ray fluxes is included within the neutrino flux calculation with parameters obtained in a global fit to recent cosmic ray flux measurements. The uncertainty of the atmospheric neutrino flux has been evaluated when using the updated hadronic interaction and cosmic ray flux models. The νμ flux uncertainty has been found to decrease from ∼15% estimated on the 2004 fluxes to ∼5-10% in this updated flux estimate

Horsetail Matching for Optimization Under Probabilistic, Interval and Mixed Uncertainties

The importance of including uncertainties in the design process of aerospace systems is becoming increasingly recognized, leading to the recent development of many techniques for optimization under uncertainty. Most existing methods represent uncertainties in the problem probabilistically; however, in many real life design applications it is often difficult to assign probability distributions to uncertainties without making strong assumptions. Existing approaches for optimization under different types of uncertainty mostly rely on treating combinations of statistical moments as separate objectives, but this can give rise to stochastically dominated designs. Horsetail matching is a flexible approach to optimization under any mix of probabilistic and interval uncertainties that overcomes some of the limitations of existing approaches. The formulation delivers a single, differentiable metric as the objective function for optimization. It is demonstrated on algebraic test problems and the design of a flying wing using a coupled aero-structural analysis code.Engineering and Physical Sciences Research CouncilUnited States. Office of Naval Research. Multidisciplinary University Research Initiative (Award Number FA9550-15-1-0038

An iron(ii) spin-crossover metallacycle from a back-to-back bis-[dipyrazolylpyridine]

The syntheses of 4-mercapto-2,6-di(pyrazol-1-yl)pyridine (bppSH) and bis[2,6-di(pyrazol-1-yl)pyrid-4-yl]disulfide (bppSSbpp) are reported. In contrast to previously published “back-to-back” bis-[2,6-di(pyrazol-1-yl)pyridine] derivatives, which form coordination polymers with transition ions that are usually insoluble, bppSSbpp yields soluble oligomeric complexes with iron(II) and zinc(II). Mass spectrometry and DOSY data show that [{Fe(μ-bppSSbpp)}n]2n+ and [{Zn(μ-bppSSbpp)}n]2n+ form tetranuclear metallacycles in nitromethane solution (n = 4), although 1H NMR and conductivity measurements imply the iron compound may undergo more fragmentation than its zinc congener. Both [{Fe(bppSH)2]2+ and [{Fe(μ-bppSSbpp)}n]2n+ exhibit thermal spin-crossover in CD3NO2 solution, with midpoint temperatures near 245 K. The similarity of these equilibria implies there is little cooperativity between the iron centres in the metallacyclic structures

Exploration of the Internet Controlled \u27Rent-a-Factory\u27 Concept

There are several robots and other devices which can now be controlled over the Internet. It is possible that an expansion of this concept ultimately leading to an Internet controlled factory could assist Australia overcome the \u27tyranny\u27 both of distance and of small production volumes. This paper discusses initial work being performed to investigate the relevance and practicality of the Internet for remote factory operations. A review of current Internet controlled equipment is presented. New experimental work involving the development of a web based graphical interface enabling clear observation and control of an Adept-One robot over the World Wide Web is also described

On Emancipation Day

https://digitalcommons.library.umaine.edu/mmb-vp/3493/thumbnail.jp

Motor vehicle and pedal cycle conspicuity: part 3 - vehicle mounted warning beacons. Summary report.

Accident studies suggest that the early detection and identification of other types of road users is likely to be a safety benefit to drivers, and one means for achieving this is through the use of vehicle-mounted warning beacons. A review of previous research, current technology, standards and regulations, and the views of relevant parties confirms the contribution of warning beacons in this respect. It also indicates that the warning beacons available in the market are largely governed by the restrictions imposed by the relevant regulations. However contact with various warning beacon user groups suggests that these designs are not as effective as they would wish and may in certain instances be giving rise to disbenefits to other road users. A rigorous scientific test programme identified those factors which make warning beacons more conspicuous and specific consideration was given to those vehicles, fitted with amber warning beacons, which work within environments of flashing amber road beacons. Disbenefits of warning beacon design, in terms of disability glare, discomfort glare, distraction and eleptogenesis, were also investigated. It is recommended that the users of warning beacons be prioritised with the highest priority group being allocated the top values of those features which make warning beacons conspicuous (subject to consideration of the disbenefits likely to be generated). Road trials should be undertaken to further refine the recommendations

Motor vehicle conspicuity: an assessment of the contribution of retro reflective and fluorescent materials.

Accident data suggests that the conspicuity of large vehicles, and the perception of closing speed to them, are contributory factors in accident causation. Ergonomic principles indicate that improved luminance and colour contrast, as well as outlining the vehicle form, are likely to increase conspicuity. A review of previous research, current on-the-road practices and the materials available shows that retro-reflective and fluorescent materials can be applied to vehicles to increase their night-time and daytime conspicuity. If applied in outline form, such materials may also assist in judgements of separation distance. Experimental work confirmed the benefits of retro-reflective and fluorescent materials, particularly if applied in outline form. The ECE104 marking formats performed at least as well as, and frequently better than, the current ECE70 markings in terms of conspicuity. The markings assisted in the detection of a pedestrian located beside the vehicle and visual discomfort, caused by the luminance of the materials, was minimal. The introduction of the ECE104 marking formats was therefore recommended. Public opinion indicated that the colour red was recognised with 99% accuracy and was strongly associated with signifying the rear of a vehicle. It would therefore be beneficial to use red markings to the rear of vehicles but only if the following recommendations are met: they must be employed as full or partial contours, applied in conjunction with the ECE70 markings and be located no closer than 200mm to the vehicle’s brake lights. It is also recommended that combined fluorescent-retro-reflective materials should be permitted under ECE104, subject to their meeting the colorimetric requirements, since they are likely to be of benefit to daytime conspicuity and some night-time aspects, whilst imposing no severe disbenefits

Motor vehicle and pedal cycle conspicuity: part 1- vehicle mounted warning beacons. Summary report.

Accident studies suggest that the early detection and identification of other types of road users is likely to be a safety benefit to drivers, and one means for achieving this is through the use of vehicle-mounted warning beacons. A review of previous research, current technology, standards and regulations, and the views of relevant parties confirms the contribution of warning beacons in this respect. It also indicates that the warning beacons available in the market are largely governed by the restrictions imposed by the relevant regulations. However contact with various warning beacon user groups suggests that these designs are not as effective as they would wish and may in certain instances be giving rise to disbenefits to other road users. A rigorous scientific test programme identified those factors which make warning beacons more conspicuous and specific consideration was given to those vehicles, fitted with amber warning beacons, which work within environments of flashing amber road beacons. Disbenefits of warning beacon design, in terms of disability glare, discomfort glare, distraction and eleptogenesis, were also investigated. It is recommended that the users of warning beacons be prioritised with the highest priority group being allocated the top values of those features which make warning beacons conspicuous (subject to consideration of the disbenefits likely to be generated). Road trials should be undertaken to further refine the recommendations