4,031 research outputs found
Testing of Large Diameter Fresnel Optics for Space Based Observations of Extensive Air Showers
The JEM-EUSO mission will detect extensive air showers produced by extreme energy cosmic rays. It operates from the ISS looking down on Earth's night time atmosphere to detect the nitrogen fluorescence and Cherenkov produce by the charged particles in the EAS. The JEM-EUSO science objectives require a large field of view, sensitivity to energies below 50 EeV, and must fit within available ISS resources. The JEM-EUSO optic module uses three large diameter, thin plastic lenses with Fresnel surfaces to meet the instrument requirements. A bread-board model of the optic has been manufactured and has undergone preliminary tests. We report the results of optical performance tests and evaluate the present capability to manufacture these optical elements
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MAZI Deliverable Report D2.4: Design, progress and evaluation of the Deptford CreekNet pilot (version 1)
This deliverable reports on the design, progress and evaluation of the MAZI pilot conducted in Deptford, London by The Open University and SPC from May to November 2016 (months 5 to 11 of the MAZI project). This pilot study explores how the MAZI approach and toolkit might support the resolution of local sustainability challenges encountered by groups and individuals working and living in and around the Deptford Creek area, in south east London (UK). Within MAZI, this is described as the initial Community Engagement phase of the CreekNet pilot study (Phase 1).
We report on the progress by referring to Holliman et al.’s 6P’s - six principles of engaged research (In Press; 2013). Originally designed to help universities plan and reflect on public engagement with research, adhering to the 6Ps ensures we don't simply impart wisdom to publics through one-way forms of communication but that we seek to involve multiple stakeholder perspectives, engaging communities as equal partners and considering how the research is likely to impact our community partners. In Phase 1 of our pilot the 6Ps resonates with the MAZI approach of seeking to work alongside local communities and have helped guide us towards achieving the following:
● ‘Preparedness’: identifying local contexts, understanding of the challenges to be faced, the researchers’ preparations for dealing with these challenges
● ‘Politics’: understanding the local social and political contexts in which the research would be carried out
● ‘People’: identifying the people that will be involved or affected by the work: the researchers, the community partners with whom we engaged, other community participants, others affected by the work
● ‘Purposes’: clarifying the aims and objectives of the research from the perspective of MAZI, the participants involved and other stakeholders
● ‘Processes’: pinning down the approach, methods and techniques that would be followed by the research team
● ‘Performances’: considering what was found and the extent to which this met the objectives of the research
By referring to the 6Ps, the sections that follow provide an overview of the pilot context and an outline of the design processes undertaken, drawing on participatory action research approaches. We introduce the pilot team and the potential community partners which we initially identified, and describe their high level concerns. This is followed by an overview of the pilot design, taking a participatory research approach, considering community mapping, and undertaking community engagement and outreach events.
We then overview the evaluation of progress made in relation to these community engagement activities, and report on what we learnt regarding the purposes of MAZI from the perspective of our community partners. We describe how we have used the early prototypes of the MAZI toolkit, and reflect on insights from community partners that emerged from the pilot process so far that have implications for specific development needs for Creeknet pilot, and appear relevant for the project at large.
Finally the report ends with a discussion of the extent to which we have met the objectives of Phase 1 and concludes with an outlook to the plans we have for the following Phase 2 of the pilot that we will undertake in months 13-18
Topological complexity of motion planning in projective product spaces
We study Farber's topological complexity (TC) of Davis' projective product
spaces (PPS's). We show that, in many non-trivial instances, the TC of PPS's
coming from at least two sphere factors is (much) lower than the dimension of
the manifold. This is in high contrast with the known situation for (usual)
real projective spaces for which, in fact, the Euclidean immersion dimension
and TC are two facets of the same problem. Low TC-values have been observed for
infinite families of non-simply connected spaces only for H-spaces, for finite
complexes whose fundamental group has cohomological dimension not exceeding 2,
and now in this work for infinite families of PPS's. We discuss general bounds
for the TC (and the Lusternik-Schnirelmann category) of PPS's, and compute
these invariants for specific families of such manifolds. Some of our methods
involve the use of an equivariant version of TC. We also give a
characterization of the Euclidean immersion dimension of PPS's through
generalized concepts of axial maps and, alternatively, non-singular maps. This
gives an explicit explanation of the known relationship between the generalized
vector field problem and the Euclidean immersion problem for PPS's.Comment: 16 page
THE RELIABILITY OF THE 12-ITEM GRIT SCALE AMONG CROSSFIT PARTICIPANTS
Crossfit participation has experienced exponential growth. Like other sports, it may be that successful participation in Crossfit would rely upon a construct known as grit. Grit is considered to be a combination of perseverance of effort (PE) and consistency of interest (CI) and has been assessed in other populations with the 12-point Grit Scale. The ability to reliably assess grit among Crossfit participants may allow participants and coaches to monitor the constructs of PE and CI in order to further develop Crossfit participation skills. Hence, the purpose of this study was to examine the reliability of the 12-point Grit Scale among adult Crossfit participants. The 12-point Grit Scale was electronically administered twice to 25 adult Crossfit participants (female:11, male:14) separated by at least two weeks. The results of the two administrations of the 12-point Grit Scale were then compared with a battery of statistical analyses in order to assess the reliability of the 12-point Grit Scale. The test-retest 12-point Grit Scale scores were: 49.8±5.3 and 50.2±5.4. The reliability statistics along with 90% confidence limits were as follows: interclass reliability coefficient was r=0.87 (UL:0.94, LL:0.73), intraclass reliability coefficient was ICC=0.91 (UL:0.96, LL:0.83), Standard Error of Measurement (SEm)=1.6 (UL:2.2, LL:1.3), ∆Means 12-point Grit Scores= -0.3±2.3 (UL:0.6, LL:-1.2), and typical error CV% =3.4 (UL:4.8, LL:2.7). The Bland-Altman plot suggested agreement between the two administrations of the 12-point Grit Scale with no evidence of heteroscedasticity. The results of the 12-point Grit Scale and subscales ranged from moderately-high to excellent reliability among adult Crossfit participants. Article visualizations
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National Science Foundation (Award# 1920430
Man-made Fibres? The Split Personalities of Victorian Manliness
This essay investigates the textual traces of a split that was central to the Victorian conception of manliness: the contradiction of gentlemanliness which demanded both the capacity to commit violence and the requirement to be ‘civilized’. It suggests that there is a fault line running through the fabric of masculinity which can be seen in the texts which train boys to become men, which remember and reconstruct that training and which consider manliness in its mature forms. A man is a subject who acts; he is also subjected to forces which he does not control. In fiction, long and short, and in poetry, masculinity is repeatedly shown to be both contested and constructed – a man-made fibre, not a natural or god-given status. From Tennyson to Wilde, there is a tear in the cloth. Keywords: Victorian manliness and masculinity; gentlemanliness; Alfred Tennyson; Charles Dickens; Rudyard Kipling; Saki (H. H. Munro); Oscar Wilde; Robert Louis Stevenson
Phylogeny, diversification, and biogeography of a hemiclonal hybrid system of native Australian freshwater fishes (Gobiiformes:Gobioidei: Eleotridae: Hypseleotris)
BACKGROUND: Carp gudgeons (genus Hypseleotris) are a prominent part of the Australian freshwater fish fauna, with species distributed around the western, northern, and eastern reaches of the continent. We infer a calibrated phylogeny of the genus based on nuclear ultraconserved element (UCE) sequences and using Bayesian estimation of divergence times, and use this phylogeny to investigate geographic patterns of diversification with GeoSSE. The southeastern species have hybridized to form hemiclonal lineages, and we also resolve relationships of hemiclones and compare their phylogenetic placement in the UCE phylogeny with a hypothesis based on complete mitochondrial genomes. We then use phased SNPs extracted from the UCE sequences for population structure analysis among the southeastern species and hemiclones. RESULTS: Hypseleotris cyprinoides, a widespread euryhaline species known from throughout the Indo-Pacific, is resolved outside the remainder of the species. Two Australian radiations comprise the bulk of Hypseleotris, one primarily in the northwestern coastal rivers and a second inhabiting the southeastern region including the Murray–Darling, Bulloo-Bancannia and Lake Eyre basins, plus coastal rivers east of the Great Dividing Range. Our phylogenetic results reveal cytonuclear discordance between the UCE and mitochondrial hypotheses, place hemiclone hybrids among their parental taxa, and indicate that the genus Kimberleyeleotris is nested within the northwestern Hypseleotris radiation along with three undescribed species. We infer a crown age for Hypseleotris of 17.3 Ma, date the radiation of Australian species at roughly 10.1 Ma, and recover the crown ages of the northwestern (excluding H. compressa) and southeastern radiations at 5.9 and 7.2 Ma, respectively. Range-dependent diversification analyses using GeoSSE indicate that speciation and extinction rates have been steady between the northwestern and southeastern Australian radiations and between smaller radiations of species in the Kimberley region and the Arnhem Plateau. Analysis of phased SNPs confirms inheritance patterns and reveals high levels of heterozygosity among the hemiclones. CONCLUSIONS: The northwestern species have restricted ranges and likely speciated in allopatry, while the southeastern species are known from much larger areas, consistent with peripatric speciation or allopatric speciation followed by secondary contact. Species in the northwestern Kimberley region differ in shape from those in the southeast, with the Kimberley species notably more elongate and slender than the stocky southeastern species, likely due to the different topographies and flow regimes of the rivers they inhabit
Real-Time On-Board Airborne Demonstration of High-Speed On-Board Data Processing for Science Instruments (HOPS)
The project called High-Speed On-Board Data Processing for Science Instruments (HOPS) has been funded by NASA Earth Science Technology Office (ESTO) Advanced Information Systems Technology (AIST) program since April, 2012. The HOPS team recently completed two flight campaigns during the summer of 2014 on two different aircrafts with two different science instruments. The first flight campaign was in July, 2014 based at NASA Langley Research Center (LaRC) in Hampton, VA on the NASA's HU-25 aircraft. The science instrument that flew with HOPS was Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) CarbonHawk Experiment Simulator (ACES) funded by NASA's Instrument Incubator Program (IIP). The second campaign was in August, 2014 based at NASA Armstrong Flight Research Center (AFRC) in Palmdale, CA on the NASA's DC-8 aircraft. HOPS flew with the Multifunctional Fiber Laser Lidar (MFLL) instrument developed by Excelis Inc. The goal of the campaigns was to perform an end-to-end demonstration of the capabilities of the HOPS prototype system (HOPS COTS) while running the most computationally intensive part of the ASCENDS algorithm real-time on-board. The comparison of the two flight campaigns and the results of the functionality tests of the HOPS COTS are presented in this paper
Physics of InAIAs/InGaAs Heterostructure Field-Effect Transistors
Contains an introduction, reports on two research projects and a list of publications.Joint Services Electronics Program Contract DAAL03-92-C-0001Joint Services Electronics Program Grant DAAH04-95-1-0038Raytheon Corporation Contract 90-58203Texas Instruments Agreement dated 08/14/9
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