1,197 research outputs found
The value of experiments in futures and foresight science as illustrated by the case of scenario planning
An already pressing need to evidence the effectiveness of futures and foresight tools has been further amplified by the coronavirus pandemic, which highlighted more mainstream tools’ difficulty with uncertainty. In light of this, the recent discussion in this journal on providing futures and foresight science with a stronger scientific basis is welcome. In this discussion critical realism has been proffered as a useful philosophical foundation and experiments a useful method for improving this field’s scientific basis. Yet, experiments seek to isolate specific causal effects through closure (i.e., by controlling for all extraneous factors) and this may cause it to jar with critical realism’s emphasis on uncertainty and openness. We therefore extend the recent discussion on improving the scientific basis of futures and foresight science by doing three things. Firstly, we elaborate on critical realism and why the experimental method may jar with it. Secondly, we explain why the distinction between a conceptual and a direct replication can help overcome this jarring, meaning experiments can still be a valuable research tool for a futures and foresight science underpinned by critical realism. Thirdly, we consider the appropriate unit of analysis for experiments on futures and foresight tools. In so doing, we situate the recent discussion on improving the scientific basis of futures and foresight science within the much longer running one on improving the scientific basis of business, management and strategy research more broadly. We use the case of scenario planning to illustrate our argument in relation to futures and foresight science
Creation of 3D models from large unstructured image and video datasets
Exploration of various places using low-cost camera solutions over decades without having a photogrammetric application in mind has resulted in large collections of images and videos that may have significant cultural value. The purpose of collecting this data is often to provide a log of events and therefore the data is often unstructured and of varying quality. Depending on the equipment used there may be approximate location data available for the images but the accuracy of this data may also be of varying quality. In this paper we present an approach that can deal with these conditions and process datasets of this type to produce 3D models. Results from processing the dataset collected during the discovery and subsequent exploration of the HMAS Sydney and HSK Kormoran wreck sites shows the potential of our approach. The results are promising and show that there is potential to retrieve significantly more information from many of these datasets than previously thought possible
Investigation into the relationship between adolescents’ perceived and actual fundamental movement skills and physical activity
Abstract Objectives: To explore the relationship between fundamental movement skill (FMS) competence, perceived FMS competence and physical activity (PA) in adolescents. Methods: The Test of Gross Motor Development (TGMD), the TGMD-2 and the Victorian Skills manual were used to assess FMS competence (locomotor, object control and stability). The Physical Self Confidence scale was used to assess perceived FMS competence (locomotor, object control and stability). Moderate to vigorous intensity PA (MVPA) was measured via accelerometry. Multi-level modelling analyses was used to examine: (i) actual FMS as the predictor and perceived FMS as the outcome, (ii) perceived FMS as the predictor and MVPA as the outcome, and (iii) actual FMS as the predictor and MVPA as the outcome. All analyses were completed for each subtest of FMS (locomotor, object control and stability). Results: A total of 584 adolescents (boys n = 278) aged 12.82 – 15.25 years (M 13.78, SD .42) participated in this study. Actual stability was associated with perceived stability (p<.01) and MVPA (p<.05) in boys. This was not found true for girls, however actual locomotor skills were associated with MVPA (p≤.05). Boys scored significantly higher than girls for FMS proficiency, perceived FMS and MVPA (p<.05). Discussion: Gender differences may exist due to cultural gender differences in sport participation norms. Considering the magnitude of physical and psychological changes occurring during adolescence, it is recommended to track young people over time to better understand the relationship between perceived and actual FMS, as well as PA participation. Keywords: physical activity, motor competence, adolescent
The Youth-Physical Activity Towards Health (Y-PATH) intervention: Results of a 24 month cluster randomised controlled trial
Low levels of physical activity in youth are an issue internationally, with the age related decline in levels over the adolescent period of particular concern. This study evaluated a multi-component school-based intervention (Y-PATH: Youth-Physical Activity Towards Health), focused on halting the age-related decline in physical activity of youth in early adolescence. A cluster randomized controlled trial in 20 post primary schools (10 control, 10 intervention) was conducted. Data were collected from all 20 schools at baseline (2013), and 12 months (2014), and from 10 of these schools (5 intervention) at 24 months (2015). The setting was mixed gender post primary schools residing in the greater area of Dublin, Ireland. Principals from each school were asked to nominate one first year class group attending their school in September 2013 to participate in the study (N = 564). Intervention schools implemented the Y-PATH whole school intervention, comprising teacher component, parent component, and PE component; while control schools continued with usual care. The main outcome measure was accelerometer derived average minutes of daily moderate to vigorous physical activity (MVPA). Data were analysed from October 2015 -November 2017. At baseline 490 participants were assessed (mean age 12.78y ± .42). Results of the multilevel regression analysis confirmed that there was a significant time intervention effect, and this was predominantly contributed by the difference between control and intervention groups within females. Findings support the case for national dissemination of the Y-PATH intervention so that the knowledge learned can be translated to routine practice in schools
Spitzer Space Telescope Observations of the Nucleus of Comet 103P/Hartley 2
We have used the Spitzer Space Telescope InfraRed Spectrograph (IRS) 22-μm peakup array to observe thermal emission from the nucleus and trail of comet 103P/Hartley 2, the target of NASA’s Deep Impact Extended Investigation (DIXI). The comet was observed on UT 2008 August 12 and 13, while 5.5 AU from the Sun. We obtained two 200 frame sets of photometric imaging over a 2.7 hr period. To within the errors of the measurement, we find no detection of any temporal variation between the two images. The comet showed extended emission beyond a point source in the form of a faint trail directed along the comet’s antivelocity vector. After modeling and removing the trail emission, a NEATM model for the nuclear emission with beaming parameter of 0.95 ± 0.20 indicates a small effective radius for the nucleus of 0.57 ± 0.08 km and low geometric albedo 0.028 ± 0.009 (1σ). With this nucleus size and a water production rate of 3 × 10^(28) molecules s^(-1) at perihelion, we estimate that ~100% of the surface area is actively emitting volatile material at perihelion. Reports of emission activity out to ~5 AU support our finding of a highly active nuclear surface. Compared to Deep Impact’s first target, comet 9P/Tempel 1, Hartley 2’s nucleus is one-fifth as wide (and about one-hundredth the mass) while producing a similar amount of outgassing at perihelion with about 13 times the active surface fraction. Unlike Tempel 1, comet Hartley 2 should be highly susceptible to jet driven spin-up torques, and so could be rotating at a much higher frequency. Since the amplitude of nongravitational forces are surprisingly similar for both comets, close to the ensemble average for ecliptic comets, we conclude that comet Hartley 2 must have a much more isotropic pattern of time-averaged outgassing from its nuclear surface. Barring a catastrophic breakup or major fragmentation event, the comet should be able to survive up to another 100 apparitions (~700 yr) at its current rate of mass loss
Hubble Space Telescope Observations of Comet 9P/Tempel 1 during the Deep Impact Encounter
We report on the Hubble Space Telescope program to observe periodic comet
9P/Tempel 1 in conjunction with NASA's Deep Impact mission. Our objectives were
to study the generation and evolution of the coma resulting from the impact and
to obtain wide-band images of the visual outburst generated by the impact. Two
observing campaigns utilizing a total of 17 HST orbits were carried out: the
first occurred on 2005 June 13-14 and fortuitously recorded the appearance of a
new, short-lived fan in the sunward direction on June 14. The principal
campaign began two days before impact and was followed by contiguous orbits
through impact plus several hours and then snapshots one, seven, and twelve
days later. All of the observations were made using the Advanced Camera for
Surveys (ACS). For imaging, the ACS High Resolution Channel (HRC) provides a
spatial resolution of 36 km (16 km/pixel) at the comet at the time of impact.
Baseline images of the comet, made prior to impact, photometrically resolved
the comet's nucleus. The derived diameter, 6.1 km, is in excellent agreement
with the 6.0 +/- 0.2 km diameter derived from the spacecraft imagers. Following
the impact, the HRC images illustrate the temporal and spatial evolution of the
ejecta cloud and allow for a determination of its expansion velocity
distribution. One day after impact the ejecta cloud had passed out of the
field-of-view of the HRC.Comment: 15 pages, 14 postscript figures. Accepted for publication in Icarus
special issue on Deep Impac
First Galileo image of asteroid 243 Ida
The second spacecraft encounter with an asteroid has yielded an unprecedentedly high resolution portrait of 243 Ida. On 28 Aug. 1993, Galileo obtained an extensive data set on this small member of the Koronis family. Most of the data recorded on the tape recorder will be returned to Earth in spring 1994. A five-frame mosaic of Ida was acquired with good illumination geometry a few minutes before closest approach; it has a resolution of 31 to 38 m/pixel amd was played back during Sept. 1993. Preliminary analyses of this single view of Ida are summarized
Exploring young people's and youth workers' experiences of spaces for ‘youth development’: creating cultures of participation
The paper focuses on the emergence of ‘positive youth development’ and its impact on older, more established practices of working with young people, such as youth work. Drawing on ethnographic fieldwork in England between 2004 and 2006, in particular young people's and youth workers' accounts of participating in youth work, the analysis engages with the social spaces in which youth work takes place and asks key questions about why young people might participate in youth spaces, what they get out of participating and how such spaces can promote cultures of participation. The analysis shows that such spaces provide young people and their communities with biographical continuity and time becomes a key component for sustaining such spaces. The argument is made for a more nuanced understanding of what young people get out of their participation in youth spaces, and for an epistemological approach to youth praxis that embraces the messiness and inequalities of lived experience
Design of a new movement competence assessment for children aged 8–12: A Delphi poll study
Assessing children's movement competence (MC) offers numerous benefits for academics, practitioners, clinicians and children, allowing individuals to meet children's developmental needs and improve their MC. Yet, there is concern that currently available assessment tools only provide a single plane (fundamental movement skills) perspective of a child's MC. The aim of this study was to elicit the expert opinion of a mixture of academics and practitioners from a variety of fields (research, education, sport, physiotherapy, athletic therapy) to design a tool to measure both the fundamental and functional movement skills of children aged 8–12. A three-round Delphi poll with an international panel of 17 academics ( n = 8) and practitioners ( n = 9) was conducted. The consensus was that the assessment should assess (a) object manipulation, (b) locomotor, and (c) stability MC and the assessment layout should be dynamic, incorporating a hybrid model of stations and a circuit. Expert consensus was that most skills were to be performed using the dominant and non-dominant side, with object manipulation skills assessed using process and product criteria. The consensus was also that the assessment should have varied ‘layers’ of marking criteria to cater for varying assessor expertise and have a series of ‘add-on” elements to provide a more detailed evaluation should it be needed. These findings present the foundation and content validity of an assessment which takes a dualistic view of children's movement skills, that could be used across several environments (schools, sports clubs, clinical settings, etc.) and could be suitable for use with a large group of children
Detection of CN gas in Interstellar Object 2I/Borisov
The detection of Interstellar Objects passing through the Solar System offers
the promise of constraining the physical and chemical processes involved in
planetary formation in other extrasolar systems. While the effect of outgassing
by 1I/2017 U1 ('Oumuamua) was dynamically observed, no direct detection of the
ejected material was made. The discovery of the active interstellar comet
2I/Borisov means spectroscopic investigations of the sublimated ices is
possible for this object. We report the first detection of gas emitted by an
interstellar comet via the near-UV emission of CN from 2I/Borisov at a
heliocentric distance of = 2.7 au on 2019 September 20. The production rate
was found to be Q(CN) = s, using a simple
Haser model with an outflow velocity of 0.5 km s. No other emission was
detected, with an upper limit to the production rate of C of
s. The spectral reflectance slope of the dust coma over
\AA\ \AA \ is steeper than at longer wavelengths, as
found for other comets. Broad band photometry on 2019 September 19 gave a
dust production rate of cm. Modelling of the observed gas and
dust production rates constrains the nuclear radius to km assuming
reasonable nuclear properties. Overall, we find the gas, dust and nuclear
properties for the first active Interstellar Object are similar to normal Solar
System comets.Comment: 9 pages, 4 figures, accepted for publication in ApJ
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