On the Structure and Morphology of the `Diffuse Ionized Medium' in Star-Forming Galaxies

Deep H$\alpha$ images of a sample of nearby late-type spiral galaxies have been analyzed to characterize the morphology and energetic significance of the ``Diffuse Ionized Medium'' (DIM). We find that the DIM properties can be reasonably unified as a function of relative surface brightness, by using a new method to quantify the DIM importance in galaxies. This new approach is more consistent with the fundamentally morphological definition of the DIM as being `Diffuse', compared to the traditional way adopted in previous studies that could only isolate the DIM based on an absolute surface brightness criterion. Our results suggest that the variation of the DIM's significance among the galaxies is small enough so that the fractional contribution of the DIM to the global H$\alpha$ luminosity in the galaxies is fairly constant, as has been observed. We found a smooth structural transition from HII regions to the DIM, suggesting that the ionizing energy for the DIM mainly comes from HII regions.Comment: 30 pages, 12 figures, AASTeX styl

Practicum placements: An innovative opportunity to foster new skills for future professionals in a cross-university collaboration in Western Australia

Murdoch University in order to share its collaborative approach to supporting future generations of library professionals organised its first group practicum project in 2017. The project targeted a group of library students from Curtin University with an interest in science fiction. Seven students were recruited for a practicum placement to create a collection development report with recommendations on the management of the library’s Science Fiction Collection. The practicum project was a success, as the students delivered an industry relevant report in an environment that resembles the dynamics of a team project. The Library experience was also successful due to the development of a partnership with Curtin University’s Placement Coordinator and the engagement of Murdoch Library team to support the student experience and the outcomes of this project. In 2018, the Library decided to develop a new project in conjunction with Curtin University. This time, the Library collaborated with the Curtin University lecturers in creating a new project, from inception to completion, to consolidate the students’ knowledge and experience in information literacy. In 2018, five students carried out a project to create a Special Collections digital learning object and two other projects including the indexing of fanzines using Dublin Core Metadata Elements and a presentation to all Library staff. The 2018 project proved to be another success for both universities and caught the attention of others in Western Australia. As a result, Murdoch decided to expand its partnership with Curtin University and engaged with other Universities to help them develop similar practicum experiences with the view of developing future partnerships for the benefit of the library and information industry. This paper will explore Murdoch’s approach to support the library industry in Western Australia through collaboration, engagement and partnerships. The paper will also focus on the lessons learnt and future collaborations following Murdoch’s partnership model. Keywords: group practicum placements, partnerships, university libraries, library and information skills, Library and Information students, engagement, special collections, workplace-based learning

The Cycling route trip planning APP

Treballs Finals del Màster en Creación y Gestión de Empresas Innovadoras y de Base Tecnológica, Facultat d'Economia i Empresa, Universitat de Barcelona, Curs: 2022-2023, Tutor: Adriana EspinetThe fitness industry has experienced significant growth in recent years. As research continues to grow, it is increasingly recognized that physical activity is essential for the well-being of individuals. Moreover, as a result of the COVID-19 pandemic, outdoor physical activities have become more prevalent than ever before, which has led to an increase in bicycle sales and cycling as a mode of transportation. For example, in the United Kingdom, bicycle sales increased by 63% (Reid, 2020), and cycling levels rose by as much as 300% on some days during the lockdown period (2019-2021) (Sutton,2020). Furthermore, in recent years there has been a noticeable trend towards promoting sustainable practices and eco-tourism. One form of eco-tourism that has gained significant attention worldwide is cycle tourism. Cycle tourism, also known as bicycle tourism, is any type of tourism that entails travelling by bicycle and encompasses many different forms such as long-distance cycling trips, guided tours, and self-guided rides. Expedite by the COVID-19 pandemic and consumer-driven ventures to explore nature, the demand for cycle tourism is growing across the globe (Grand View Review, 2022). In 2019, Europe had the largest share of the cycling tourism market, accounting for approximately 40% of the global market (Global View Research, 2022)

HIIphot: Automated Photometry of HII Regions Applied to M51

We have developed a robust, automated method, hereafter designated HIIphot, which enables accurate photometric characterization of HII regions while permitting genuine adaptivity to irregular source morphology. HIIphot utilizes object-recognition techniques to make a first guess at the shapes of all sources then allows for departure from such idealized ``seeds'' through an iterative growing procedure. Photometric corrections for spatially coincident diffuse emission are derived from a low-order surface fit to the background after exclusion of all detected sources. We present results for the well-studied, nearby spiral M51 in which 1229 HII regions are detected above the 5-sigma level. A simple, weighted power-law fit to the measured H-alpha luminosity function (HII LF) above log L_H-alpha = 37.6 gives alpha = -1.75+/-0.06, despite a conspicuous break in the HII LF observed near L_H-alpha = 10^38.9. Our best- fit slope is marginally steeper than measured by Rand (1992), perhaps reflecting our increased sensitivity at low luminosities and to notably diffuse objects. HII regions located in interarm gaps are preferentially less luminous than counterparts which constitute M51's grand-design spiral arms and are best fit with a power-law slope of alpha = -1.96+/-0.15. We assign arm/interarm status for HII regions based upon the varying surface brightness of diffuse emission as a function of position throughout the image. Using our measurement of the integrated flux contributed by resolved HII regions in M51, we estimate the diffuse fraction to be approximately 0.45 -- in agreement with the determination of Greenawalt et al. (1998). Automated processing of degraded datasets is undertaken to gauge systematic effects associated with limiting spatial resolution and sensitivity.Comment: 41 pages, 14 figures, Postscript version with high-resolution figures at ftp://ftp.aoc.nrao.edu/staff/dthilker/preprint

Tension and stiffness of the hard sphere crystal-fluid interface

A combination of fundamental measure density functional theory and Monte Carlo computer simulation is used to determine the orientation-resolved interfacial tension and stiffness for the equilibrium hard-sphere crystal-fluid interface. Microscopic density functional theory is in quantitative agreement with simulations and predicts a tension of 0.66 kT/\sigma^2 with a small anisotropy of about 0.025 kT and stiffnesses with e.g. 0.53 kT/\sigma^2 for the (001) orientation and 1.03 kT/\sigma^2 for the (111) orientation. Here kT is denoting the thermal energy and \sigma the hard sphere diameter. We compare our results with existing experimental findings

Fast 2.5D Finite Element Simulations of Borehole Resistivity Measurements

We develop a rapid 2.5-dimensional (2.5D) finite element method for simulation of borehole resistivity measurements in transversely isotropic (TI) media. The method combines arbitrary high-order $H^1$ - and $H$ (curl)-conforming spatial discretizations. It solves problems where material properties remain constant along one spatial direction, over which we consider a Fourier series expansion and each Fourier mode is solved independently. We propose a novel a priori method to construct quasi-optimal discretizations in physical and Fourier space. This construction is based on examining the analytical (fundamental) solution of the 2.5D formulation over multiple homogeneous spaces and assuming that some of its properties still hold for the 2.5D problem over a spatially heterogeneous formation. In addition, a simple parallelization scheme over multiple measurement positions provides efficient scalability. Our method yields accurate borehole logging simulations for realistic synthetic examples, delivering simulations of borehole resistivity measurements at a rate faster than 0.05 s per measurement location along the well trajectory on a 96-core computer

Finite Element Simulations of Logging-While-Drilling and Extra-Deep Azimuthal Resistivity Measurements using Non-Fitting Grids

We propose a discretization technique using non-fitting grids to simulate magnetic field-based resistivity logging measurements. Non-fitting grids are convenient because they are simpler to generate and handle than fitting grids when the geometry is complex. On the other side, fitting grids have been historically preferred because they offer additional accuracy for a fixed problem size in the general case. In this work, we analyse the use of non-fitting grids to simulate the response of logging instruments that are based on magnetic field resistivity measurements using 2.5D Maxwell’s equations. We provide various examples demonstrating that, for these applications, if the finite element matrix coefficients are properly integrated, the accuracy loss due to the use of non-fitting grids is negligible compared to the case where fitting grids are employed