Multiple curved descending approaches and the air traffic control problem

A terminal area air traffic control simulation was designed to study ways of accommodating increased air traffic density. The concepts that were investigated assumed the availability of the microwave landing system and data link and included: (1) multiple curved descending final approaches; (2) parallel runways certified for independent and simultaneous operation under IFR conditions; (3) closer spacing between successive aircraft; and (4) a distributed management system between the air and ground. Three groups each consisting of three pilots and two air traffic controllers flew a combined total of 350 approaches. Piloted simulators were supplied with computer generated traffic situation displays and flight instruments. The controllers were supplied with a terminal area map and digital status information. Pilots and controllers also reported that the distributed management procedure was somewhat more safe and orderly than the centralized management procedure. Flying precision increased as the amount of turn required to intersect the outer mark decreased. Pilots reported that they preferred the alternative of multiple curved descending approaches with wider spacing between aircraft to closer spacing on single, straight in finals while controllers preferred the latter option. Both pilots and controllers felt that parallel runways are an acceptable way to accommodate increased traffic density safely and expeditiously

The Urban Forest and Ecosystem Services: Impacts on Urban Water, Heat, and Pollution Cycles at the Tree, Street, and City Scale

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Effect of transient pinning on stability of drops sitting on an inclined plane

We report on new instabilities of the quasi-static equilibrium of water drops pinned by a hydrophobic inclined substrate. The contact line of a statically pinned drop exhibits three transitions of partial depinning: depinning of the advancing and receding parts of the contact line and depinning of the entire contact line leading to the drop's translational motion. We find a region of parameters where the classical Macdougall-Ockrent-Frenkel approach fails to estimate the critical volume of the statically pinned inclined drop

Potential structural material problems in a hydrogen energy system

Potential structural material problems that may be encountered in the three components of a hydrogen energy system - production, transmission/storage, and utilization - were identified. Hydrogen embrittlement, corrosion, oxidation, and erosion may occur during the production of hydrogen. Hydrogen embrittlement is of major concern during both transmission and utilization of hydrogen. Specific materials research and development programs necessary to support a hydrogen energy system are described

Effects of passion, experience, and cultural politics on classical musicians’ practice during the COVID-19 pandemic

The widespread cancelation of cultural events during the early 2020 stages of the COVID-19 pandemic led professional performing musicians across the world to experience an increasing economic fragility that threatened their health and wellbeing. Within this “new normal,” developing countries have been at a higher risk due to their vulnerable health systems and cultural policies. Even in such difficult times, the music profession requires musicians to keep up their practicing routines, even if they have no professional commitments. This is because high level technical and expressive skills are crucial to sustaining a music career at a high performance level. However, it could be expected that not all musicians might have had the same engagement with music practice during lockdowns. In this study, we studied the experiences of 309 professional classical musicians based in European and Latin American countries with different levels of performing experience to examine their passionate (or lack thereof) engagement with music practice. Through the mixed methods combination of multigroup invariance and narrative analyses, we identified distinct profiles of musicians who displayed more harmonious or more obsessive passion orientations before and at the peak of the pandemic. We observed that musicians with higher levels of harmonious passion in particular were more capable of sustaining their practice at the peak of the pandemic and that these musicians were mostly located in Latin America—a paradox, considering that cultural politics supporting the careers of professional performing musicians and entrepreneurial education in Latin America are lacking to a great extent, especially in comparison with the European context. We explain this in terms of the “forced” self-management embraced by musicians in Latin American countries who want to engage with music practice both before and during the COVID-19 pandemic even if the music profession does not generate enough revenue for them

Inhibition of protein crystallization by evolutionary negative design

In this perspective we address the question: why are proteins seemingly so hard to crystallize? We suggest that this is because of evolutionary negative design, i.e. proteins have evolved not to crystallize, because crystallization, as with any type of protein aggregation, compromises the viability of the cell. There is much evidence in the literature that supports this hypothesis, including the effect of mutations on the crystallizability of a protein, the correlations found in the properties of crystal contacts in bioinformatics databases, and the positive use of protein crystallization by bacteria and viruses.Comment: 5 page

Built to last? the sustainability of health system improvements, interventions and change strategies: A study protocol for a systematic review

© 2017 Article author(s) (or their employer(s) unless otherwise stated in the text of the article). All rights reserved. No commercial use is permitted unless otherwise expressly granted. Introduction The sustainability of healthcare interventions and change programmes is of increasing importance to researchers and healthcare stakeholders interested in creating sustainable health systems to cope with mounting stressors. The aim of this protocol is to extend earlier work and describe a systematic review to identify, synthesise and draw meaning from studies published within the last 5 years that measure the sustainability of interventions, improvement efforts and change strategies in the health system. Methods and analysis The protocol outlines a method by which to execute a rigorous systematic review. The design includes applying primary and secondary data collection techniques, consisting of a comprehensive database search complemented by contact with experts, and searching secondary databases and reference lists, using snowballing techniques. The review and analysis process will occur via an abstract review followed by a full-text screening process. The inclusion criteria include English-language, peer-reviewed, primary, empirical research articles published after 2011 in scholarly journals, for which the full text is available. No restrictions on location will be applied. The review that results from this protocol will synthesise and compare characteristics of the included studies. Ultimately, it is intended that this will help make it easier to identify and design sustainable interventions, improvement efforts and change strategies. Ethics and dissemination As no primary data were collected, ethical approval was not required. Results will be disseminated in conference presentations, peer-reviewed publications and among policymaker bodies interested in creating sustainable health systems

Octupole strength in the neutron-rich calcium isotopes

Low-lying excited states of the neutron-rich calcium isotopes $^{48-52}$Ca have been studied via $\gamma$-ray spectroscopy following inverse-kinematics proton scattering on a liquid hydrogen target using the GRETINA $\gamma$-ray tracking array. The energies and strengths of the octupole states in these isotopes are remarkably constant, indicating that these states are dominated by proton excitations.Comment: 15 pages, 3 figure

Academic team formation as evolving hypergraphs

This paper quantitatively explores the social and socio-semantic patterns of constitution of academic collaboration teams. To this end, we broadly underline two critical features of social networks of knowledge-based collaboration: first, they essentially consist of group-level interactions which call for team-centered approaches. Formally, this induces the use of hypergraphs and n-adic interactions, rather than traditional dyadic frameworks of interaction such as graphs, binding only pairs of agents. Second, we advocate the joint consideration of structural and semantic features, as collaborations are allegedly constrained by both of them. Considering these provisions, we propose a framework which principally enables us to empirically test a series of hypotheses related to academic team formation patterns. In particular, we exhibit and characterize the influence of an implicit group structure driving recurrent team formation processes. On the whole, innovative production does not appear to be correlated with more original teams, while a polarization appears between groups composed of experts only or non-experts only, altogether corresponding to collectives with a high rate of repeated interactions

‘Play it by ear’ – teachers’ responses to ear-playing tasks during one to one instrumental lessons

This paper reports findings from the Ear Playing Project (EPP) in relation to the teaching strategies that 15 instrumental teachers adopted during one-to-one instrumental lessons whilst helping their students to copy music by ear from a recording. Overall, the teachers used a variety of strategies including singing and humming along with or without the recording, asking questions, and giving verbal explanation and positive feedback. By the end of the project the teachers indicated that the project showed them a new and enjoyable way to introduce aural-training tasks, it helped them develop their own confidence in ear-playing and it gave them the opportunity to observe and assess their students’ needs more carefully. The benefits for the students included greater enjoyment during instrumental lessons, development of aural and improvisation skills and greater confidence in instrumental playing