The Opportunity Costs of Residential Displacement Due to Coastal Land Use Restrictions: A Conceptual Framework

Community/Rural/Urban Development, Environmental Economics and Policy, Land Economics/Use, Resource /Energy Economics and Policy,

Diffusion-controlled and replacement microtextures in alkali feldspars from two pegmatites: Perth, Ontario and Keystone, South Dakota

Macro- and micro-perthitic microclines from pegmatites from Perth, Ontario (Wards catalogue 46 E 0510) and Keystone, South Dakota (Wards 46 E 5125) have been studied using light and electron microscopy. A sample of the type perthite from Perth, Ontario (Hunterian Museum, Glasgow, M2361) was compared using light microscopy. It differs in bulk composition and microtexture from the Wards sample. The Perth sample from Wards is a mesoperthite, with sub-periodic ~mm-thick albite veins near (100), with irregular surfaces. The microcline has regular tartan twins and formed from orthoclase by a continuous process. The Keystone sample is a microperthite, with non-periodic albite veins mainly in {110}. Irregular tartan twins, volumes of irregular microcline and subgrains suggest that the microcline formed by dissolution–reprecipitation. Microcline in both samples contains semicoherent cryptoperthitic albite films that formed after the development of tartan twins. The bulk compositions of these intergrowths imply exsolution below ~400°C. Diffusion parameters imply sustained heating for between 0.11 My at 400°C, 1.5 GPa and 8.4 My at 300°C, 1 GPa. Unrealistic times are required at 200°C. Subsequently, the crystals reacted with a fluid leading to replacive growth of the vein perthites. Unusually, Albite twin composition planes in replacive subgrains have sub-periodic dislocations, formed by coalescence of advancing growth twins. Processes that might lead to periodic, replacive intergrowths are discussed. The Perth and Keystone feldspars have been used for experimental work on dissolution during weathering and on anomalous thermoluminescence fading. Their microtextures make them unsuitable for obtaining properties that can be extrapolated to feldspars in general

Systematic Differences due to High Energy Hadronic Interaction Models in Air Shower Simulations in the 100 GeV-100 TeV Range

The predictions of hadronic interaction models for cosmic-ray induced air showers contain inherent uncertainties due to limitations of available accelerator data and theoretical understanding in the required energy and rapidity regime. Differences between models are typically evaluated in the range appropriate for cosmic-ray air shower arrays ($10^{15}$-$10^{20}$ eV). However, accurate modelling of charged cosmic-ray measurements with ground based gamma-ray observatories is becoming more and more important. We assess the model predictions on the gross behaviour of measurable air shower parameters in the energy (0.1-100 TeV) and altitude ranges most appropriate for detection by ground-based gamma-ray observatories. We go on to investigate the particle distributions just after the first interaction point, to examine how differences in the micro-physics of the models may compound into differences in the gross air shower behaviour. Differences between the models above 1 TeV are typically less than 10%. However, we find the largest variation in particle densities at ground at the lowest energy tested (100 GeV), resulting from striking differences in the early stages of shower development.Comment: 9 pages, 6 figures. Published by Phys Rev

Constraining cosmology and ionization history with combined 21 cm power spectrum and global signal measurements

Improvements in current instruments and the advent of next-generation instruments will soon push observational 21 cm cosmology into a new era, with high significance measurements of both the power spectrum and the mean ("global") signal of the 21 cm brightness temperature. In this paper we use the recently commenced Hydrogen Epoch of Reionization Array as a worked example to provide forecasts on astrophysical and cosmological parameter constraints. In doing so we improve upon previous forecasts in a number of ways. First, we provide updated forecasts using the latest best-fit cosmological parameters from the Planck satellite, exploring the impact of different Planck datasets on 21 cm experiments. We also show that despite the exquisite constraints that other probes have placed on cosmological parameters, the remaining uncertainties are still large enough to have a non-negligible impact on upcoming 21 cm data analyses. While this complicates high-precision constraints on reionization models, it provides an avenue for 21 cm reionization measurements to constrain cosmology. We additionally forecast HERA's ability to measure the ionization history using a combination of power spectrum measurements and semi-analytic simulations. Finally, we consider ways in which 21 cm global signal and power spectrum measurements can be combined, and propose a method by which power spectrum results can be used to train a compact parameterization of the global signal. This parameterization reduces the number of parameters needed to describe the global signal, increasing the likelihood of a high significance measurement.Comment: 16 pages, 8 figures. Revised to match accepted MNRAS version: expanded discussion of covariances between astrophysics and cosmology in Section 2.2, including two new figures; short discussion relating to KL modes added to Section 4; final results unchange

Background Rejection in Atmospheric Cherenkov Telescopes using Recurrent Convolutional Neural Networks

In this work, we present a new, high performance algorithm for background rejection in imaging atmospheric Cherenkov telescopes. We build on the already popular machine-learning techniques used in gamma-ray astronomy by the application of the latest techniques in machine learning, namely recurrent and convolutional neural networks, to the background rejection problem. Use of these machine-learning techniques addresses some of the key challenges encountered in the currently implemented algorithms and helps to significantly increase the background rejection performance at all energies. We apply these machine learning techniques to the H.E.S.S. telescope array, first testing their performance on simulated data and then applying the analysis to two well known gamma-ray sources. With real observational data we find significantly improved performance over the current standard methods, with a 20-25\% reduction in the background rate when applying the recurrent neural network analysis. Importantly, we also find that the convolutional neural network results are strongly dependent on the sky brightness in the source region which has important implications for the future implementation of this method in Cherenkov telescope analysis.Comment: 11 pages, 7 figures. To be submitted to The European Physical Journal

Image analysis and statistical modelling for measurement and quality assessment of ornamental horticulture crops in glasshouses

Image analysis for ornamental crops is discussed with examples from the bedding plant industry. Feed-forward artificial neural networks are used to segment top and side view images of three contrasting species of bedding plants. The segmented images provide objective measurements of leaf and flower cover, colour, uniformity and leaf canopy height. On each imaging occasion, each pack was scored for quality by an assessor panel and it is shown that image analysis can explain 88.5%, 81.7% and 70.4% of the panel quality scores for the three species, respectively. Stereoscopy for crop height and uniformity is outlined briefly. The methods discussed here could be used for crop grading at marketing or for monitoring and assessment of growing crops within a glasshouse during all stages of production

A Monte Carlo Template based analysis for Air-Cherenkov Arrays

We present a high-performance event reconstruction algorithm: an Image Pixel-wise fit for Atmospheric Cherenkov Telescopes (ImPACT). The reconstruction algorithm is based around the likelihood fitting of camera pixel amplitudes to an expected image template. A maximum likelihood fit is performed to find the best-fit shower parameters. A related reconstruction algorithm has already been shown to provide significant improvements over traditional reconstruction for both the CAT and H.E.S.S. experiments. We demonstrate a significant improvement to the template generation step of the procedure, by the use of a full Monte Carlo air shower simulation in combination with a ray-tracing optics simulation to more accurately model the expected camera images. This reconstruction step is combined with an MVA-based background rejection. Examples are shown of the performance of the ImPACT analysis on both simulated and measured (from a strong VHE source) gamma-ray data from the H.E.S.S. array, demonstrating an improvement in sensitivity of more than a factor two in observation time over traditional image moments-fitting methods, with comparable performance to previous likelihood fitting analyses. ImPACT is a particularly promising approach for future large arrays such as the Cherenkov Telescope Array (CTA) due to its improved high-energy performance and suitability for arrays of mixed telescope types.Comment: 13 pages, 10 figure

Notes on the germination of the endangered species Sclerolaena napiformis (Chenopodiaceae)

Sclerolaena napiformis is found on fertile plains in northern Victoria and southern New South Wales and is endangered Australia-wide. Introductory work on its germination shows that seeds cannot germinate until the woody fruit has broken down. The seeds tolerate a wide range of temperatures for germination, suggesting that germination occurs regardless of season if sufficient rain falls. Seed ageing effects reduce seed viability, but some seed is still viable after two years storage. Flower buds first appear 21 weeks from germination and some fruits have matured by week 29. In the field, plants die back to their taproots in late autumn and resprout in spring. Ninety percent of tagged plants were still alive two years later. The physiological seed dormancy imposed by an intact fruit wall provides a mechanism for the development of persistent soil seed banks. Work on the ecological significance of such banks is needed. The literature on interactions between Sclerolaena fruit and seed biology and ants is briefly reviewed

Theological education in the light of a contemporary understanding of priestly formation and ministry: proposals for action.

The project provides a rationale for a systematic view of the role of theological education in a life-long approach to priestly formation. In particular, it examines perceptions and proposals for action in relation to theological education in the context of the contemporary understanding of Roman Catholic priestly formation and ministry. This contemporary understanding involves the concepts of collaboration and mission which should occur within an ecumenical dimension. The project is divided into three parts. First, the priestly ministry is set within the changing context of theological, historical and social awareness in modem England. The argument is presented that even in a secular context a residual interest in theological and religious questions increase in a society where clergy are generally trusted and well respected. The conjunction between theological theory and actual ministerial practice is. then confronted. The argument presented here is that these two realities must be seen in inter-relationship. I argue next that priestly ministry ought to be contextualised within a particular society. I make, therefore, observations about the 'place' of the Roman Catholic Church in English history and society and in relationship to the Church of England. Secondly, I present my research concerning inter-activity which is discussed on three levels: between priests and other professionals: doctors, teachers and lawyers, the clergy acting in ecumenical partnership and between priests and the lay faithful of the Church. The emerging picture reveals considerable revaluation in other professions in which, particularly in the case of medicine and teaching the clergy have an important role to play in terms of pastoral ministry and ethical focus. A complex series of inter-relationships emerge which demand on the part of priests, a broad intellectual and pastoral vision of priestly ministry, Thirdly, parts one and two provide the foundation for part three which offers the notion of the relationship between Jesus and his disciples as a paradigm for priestly ministry and formation. Various aspects of Gospel study are explored in the context of both initial and on-going formation. The purpose of this section is to give a clear Christological focus to priestly ministry. The concluding chapter presents proposals for innovative action regarding an holistic approach to theological education which covers both initial and on-going priestly formation. This action should enable the priest to present his own vocation and professionalism in a way that can be useful and supportive to other professionals and apply the ancient faith in a contemporary context

Redundant Array Configurations for 21 cm Cosmology

Realizing the potential of 21 cm tomography to statistically probe the intergalactic medium before and during the Epoch of Reionization requires large telescopes and precise control of systematics. Next-generation telescopes are now being designed and built to meet these challenges, drawing lessons from first-generation experiments that showed the benefits of densely packed, highly redundant arrays--in which the same mode on the sky is sampled by many antenna pairs--for achieving high sensitivity, precise calibration, and robust foreground mitigation. In this work, we focus on the Hydrogen Epoch of Reionization Array (HERA) as an interferometer with a dense, redundant core designed following these lessons to be optimized for 21 cm cosmology. We show how modestly supplementing or modifying a compact design like HERA's can still deliver high sensitivity while enhancing strategies for calibration and foreground mitigation. In particular, we compare the imaging capability of several array configurations, both instantaneously (to address instrumental and ionospheric effects) and with rotation synthesis (for foreground removal). We also examine the effects that configuration has on calibratability using instantaneous redundancy. We find that improved imaging with sub-aperture sampling via "off-grid" antennas and increased angular resolution via far-flung "outrigger" antennas is possible with a redundantly calibratable array configuration.Comment: 19 pages, 11 figures. Revised to match the accepted ApJ versio