99 research outputs found
A Census of Large-Scale ( 10 pc), Velocity-Coherent, Dense Filaments in the Northern Galactic Plane: Automated Identification Using Minimum Spanning Tree
Large-scale gaseous filaments with length up to the order of 100 pc are on
the upper end of the filamentary hierarchy of the Galactic interstellar medium.
Their association with respect to the Galactic structure and their role in
Galactic star formation are of great interest from both observational and
theoretical point of view. Previous "by-eye" searches, combined together, have
started to uncover the Galactic distribution of large filaments, yet inherent
bias and small sample size limit conclusive statistical results to be drawn.
Here, we present (1) a new, automated method to identify large-scale
velocity-coherent dense filaments, and (2) the first statistics and the
Galactic distribution of these filaments. We use a customized minimum spanning
tree algorithm to identify filaments by connecting voxels in the
position-position-velocity space, using the Bolocam Galactic Plane Survey
spectroscopic catalog. In the range of , we
have identified 54 large-scale filaments and derived mass (), length (10-276 pc), linear mass density (54-8625 ), aspect ratio, linearity, velocity gradient, temperature,
fragmentation, Galactic location and orientation angle. The filaments
concentrate along major spiral arms. They are widely distributed across the
Galactic disk, with 50% located within 20 pc from the Galactic mid-plane
and 27% run in the center of spiral arms (aka "bones"). An order of 1% of the
molecular ISM is confined in large filaments. Massive star formation is more
favorable in large filaments compared to elsewhere. This is the first
comprehensive catalog of large filaments useful for a quantitative comparison
with spiral structures and numerical simulations.Comment: Accepted to ApJS. 20 pages (in aastex6 compact format), 6 figures, 1
table. See http://www.eso.org/~kwang/MSTpaper for (1) a preprint with full
resolution Fig 6, (2) filaments catalog (Table 1) in ASCII format, and (3) a
DS9 region file for the coordinates of the filament
Overtourism and Employment Outcomes for the Tourism Worker: Impacts to Labour Markets
This paper aims to undertake an ideal-typical analysis of the implications of overtourism on employment at the level of the destination
Governance implications of the UN Higher Education Sustainability Initiative
The Higher Education Sustainability Initiative (HESI, 2017a) states that higher education institutions (HEIs) are integrating the SDGs into sustainability strategies in the form of research, teaching, pedagogy, and campus practices, and to position HEIs as key drivers for achieving the UN Sustainable Development Goals (SDGs). Concern has been raised (HESI, 2017b) as to the potential impact of HEIs in helping to achieve the SDGs; the challenges faced by HEIs with integrating the SDGs into curriculum and institutional strategies; the role of partnerships for HEIs among students, faculty, government, and various stakeholders; and how the adoption of the 2030 Agenda for Sustainable Development, including the SDGs, will transform the work of HEIs. Prior research has highlighted the importance of interdisciplinary and trans-disciplinary research and studies (e.g. Mader & Rammel, 2015); and more recently Rasche et al (2017) conceive that governance systems in general can serve to make, take, or break support for the SDGs. In fact, Velazquez et al., (2005) found many obstacles preventing the success of sustainability initiatives on campuses around the world. This paper reviews progress of a sample of 300+ HEIs that are signatories to the HESI. Findings reveal a difference between HEI governance that is ‘instrumental’ and governance that is ‘holistic’ in relation to sustainability with implications for achieving the SDGs in general and for academic-business partnerships in particular. The research is supported by a grant from Enterprise Educators UK (EEUK, 2017) a network of 1,600 enterprise and entrepreneurship educators and practitioners from over 100 UK Higher and Further Education Institutions and related organisations
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