173 research outputs found
Comparison of calculated and experimental cascade performance for controlled-diffusion compressor stator blading
The mid-span section of a previously reported controlled-diffusion compressor stator has been experimentally evaluated in cascade. Measurements are taken over a range of incidence angles for blade chord Reynolds numbers from 470,000 to 690,000. Blade chord length is 12.7 cm, aspect ratio is 2.0, and solidity is 1.67. Measurements include conventional cascade performance parameters as well as blade surface pressures. Computations are made for the inviscid flow field, surface boundary layers, and loss for several of the blade inlet angle conditions, are compared against corresponding data
Applications of BMI or BSI: Differences and Revisions According to Age and Height
Validation of body-mass relationships requires a careful statistical analysis of data of normal weight individuals. BMI
(ratio between body mass and square of body height) and BSI values (ratio between mass and cube of body height) have been calculated
for 99 persons with ages between 1 day and 76 years. These BMI or BSI values have been used for least squares fits yielding mean BMI
or BSI values, their variances (providing precision), and average deviations of individual BMI/BSI values from the BMI/BSI means.
The latter allows limits to over- and underweight. For adults we found mean values of BSI of 12.36 and confirmed 21.7 for the mean
BMI; but the BSI was 1.4 times more precise than the BMI. For children shorter than 1.3 m and younger than 8 years we
found the BMI average of 15.9 and over-/underweight limits of 17.4/14.4 being significantly smaller than and incompatible with
the recommended BMI values
Making judgements about students making work : lecturers’ assessment practices in art and design.
This research study explores the assessment practices in two higher education art and design departments. The key aim of this research was to explore art and design studio assessment practices as lived by and experienced by art and design lecturers. This work draws on two bodies of pre existing research. Firstly this study adopted innovative methodological approaches that have been employed to good effect to explore assessment in text based subjects (think aloud) and moderation mark agreement (observation). Secondly the study builds on existing research into the assessment of creative practice. By applying thinking aloud methodologies into a creative practice assessment context the authors seek to illuminate the ‘in practice’ rather than espoused assessment approaches adopted. The analysis suggests that lecturers in the study employed three macro conceptions of quality to support the judgement process. These were; the demonstration of significant learning over time, the demonstration of effective studentship and the presentation of meaningful art/design work
Understanding the link between benefits from protected areas and their relationship with surrounding communities: an exploration in Costa Rica
Protected areas are an essential strategy in preserving natural resources. A central aspect of protected area
management is to maintain and improve their relationship with surrounding communities given that local
conflicts often occur over the existence or expansion of protected areas due to land-use restrictions. This
study seeks to understand the link between perceived socioeconomic and environmental benefits from
protected areas and the perceived strength of the relationship between 12 of these communities and their
corresponding protected areas in Costa Rica. In total, 365 door-to-door interviews were conducted to collect
data, and a logistic model and correlations were used to analyse the results. We found there is a significant
link between the strength of the relationship between the community and protected area and the number of
perceived socioeconomic benefits from the protected area; however, such a link does not exist with
environmental benefits. This finding suggests that policy makers and protected area managers need to
better develop and explain, in a participatory and integrated fashion, socioeconomic benefits from protected
areas to communities since the successful long-term management and survival of protected areas hinges on
these relationships. In this way, the desired goals of preserving habitats and biodiversity can be supported.Las áreas protegidas son una estrategia esencial en la preservación de los recursos naturales. En la
actualidad, un aspecto central del manejo de las áreas protegidas es mantener y mejorar su relación con las
comunidades circundantes dado el frecuente conflicto por la existencia y expansión de áreas protegidas
debido a restricciones en el uso de la tierra. En este estudio, buscamos entender la conexión entre los
beneficios socioeconómicos y ambientales percibidos por las comunidades sobre las áreas protegidas y la
fortaleza de la relación percibida entre 12 de estas comunidades y sus correspondientes áreas protegidas en
Costa Rica. En total, se realizaron 365 entrevistas casa a casa para recolectar los datos, y se utilizó un
modelo logístico y correlaciones para analizar los resultados. Encontramos que existe una conexión
significativa entre el nivel de percepción de la relación comunidad-área protegida y el número de beneficios
socioeconómicos percibidos del área protegida; sin embargo, dicha conexión no se mantiene para los
beneficios ambientales. Este resultado sugiere que los responsables de la formulación de políticas y los
administradores de áreas protegidas deberían desarrollar y explicar mejor, de una manera participativa e
integradora, los beneficios socioeconómicos adicionales de las áreas protegidas hacia las comunidades, por
cuanto la gestión a largo plazo y la supervivencia de las áreas protegidas dependen de la relación que tienen
con sus comunidades circundantes. De esta manera se pueden apoyar los objetivos deseados de
preservación de los hábitats y la biodiversidad.Les aires protégées sont un élément clé pour la préservation des ressources naturelles. L’un des
principes fondamentaux de la gestion des aires protégées est de maintenir et d'améliorer leurs relations
avec les communautés locales, car l'existence ou l'expansion des aires protégées est souvent source de
conflits, en raison des restrictions d'utilisation de ces terres. Cette étude vise à comprendre le lien entre la
perception des avantages socio-économiques et environnementaux créés par aires protégées, et la qualité
des relations entretenues par 12 communautés avec leurs aires protégées au Costa Rica. 365 entretiens en
porte-à-porte ont été menés, puis analysés grâce à un modèle logistique basé sur des corrélations afin d’en
déduire les résultats. Nous avons constaté que la qualité des relations entre la communauté et l’aire
protégée influence la perception des avantages socio-économiques provenant de l’aire protégée; cependant
ceci n’est pas le cas pour les avantages environnementaux. Ces résultats suggèrent que les décideurs et les
gestionnaires d'aires protégées se doivent de mieux présenter et expliquer, de manière intégrée et
participative, les avantages socio-économiques liés aux aires protégées, car la gestion à long terme et la
survie des aires protégées repose sur leurs bonnes relations avec les communautés. La réalisation des
objectifs attendus de la préservation des habitats et de la biodiversité sera ainsi favorisée.SFS-Center for Sustainable
Development Studies in Atenas, Costa Rica, the National
University of Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ingeniería::Instituto Investigaciones en Ingeniería (INII
Lithological constraints on borehole wall failure: a study on the Pennine Coal Measures of the United Kingdom
Stress-related borehole deformation features have been documented across the United Kingdom, most commonly as borehole breakouts and drilling induced tensile fractures (DIFs). Recent studies using borehole imaging have allowed more detailed investigation of these features and the processes that control their formation. Within the Pennsylvanian Pennine Coal Measures Group (PCM) of the United Kingdom borehole imaging has highlighted a disproportionately high number of breakouts occurring within paleosols located immediately below coal seams. To understand the processes controlling breakout formation, a 10.5 m section of core from the Melbourne 1 borehole, incorporating a typical coal seam / paleosol sequence, was analyzed using multiple techniques including: scanning electron and optical microscopy, X-Ray Fluorescence (XRF), X-ray radiography, Point Load testing, wireline petrophysics and track-based core scanning for physical properties. Strength measurements highlight that breakouts form preferentially in poorly consolidated sediments, with low tensile strength, cross-cut by listric surfaces. The formation and termination of breakouts also corresponds to zones of diagenetic iron mineral growth with a lower propensity to fail. These coincide with greater preservation of sedimentary structures and an increase in the rock’s tensile strength; this intra-unit variation in tensile strength constrains breakout length. This demonstrates that secondary diagenetic processes, including the growth of iron minerals impose, lithological controls on the formation and length of borehole breakouts within the United Kingdom PCM
Marine plastics threaten giant Atlantic Marine Protected Areas.
There has been a recent shift in global perception of plastics in the environment, resulting in a call for greater action. Science and the popular media have highlighted plastic as an increasing stressor [1,2]. Efforts have been made to confer protected status to some remote locations, forming some of the world's largest Marine Protected Areas, including several UK overseas territories. We assessed plastic at these remote Atlantic Marine Protected Areas, surveying the shore, sea surface, water column and seabed, and found drastic changes from 2013-2018. Working from the RRS James Clark Ross at Ascension, St. Helena, Tristan da Cunha, Gough and the Falkland Islands (Figure 1A), we showed that marine debris on beaches has increased more than 10 fold in the past decade. Sea surface plastics have also increased, with in-water plastics occurring at densities of 0.1 items m-3; plastics on seabeds were observed at ≤ 0.01 items m-2. For the first time, beach densities of plastics at remote South Atlantic sites approached those at industrialised North Atlantic sites. This increase even occurs hundreds of meters down on seamounts. We also investigated plastic incidence in 2,243 animals (comprising 26 species) across remote South Atlantic oceanic food webs, ranging from plankton to seabirds. We found that plastics had been ingested by primary consumers (zooplankton) to top predators (seabirds) at high rates. These findings suggest that MPA status will not mitigate the threat of plastic proliferation to this rich, unique and threatened biodiversity
Signature pedagogies for designing: A speculative framework for supporting learning and teaching in Design and Technology education
Disclosure of donor conception in the era of non-anonymity: safeguarding and promoting the interests of donor-conceived individuals?
This article responds to a debate article published in Human Reproduction earlier this year. In that article, the authors suggested that parents should be encouraged to disclose the use of donor gametes to their children given rapid and widespread advances in genetic testing and sequencing. However, there is an urgent need to engage with the assertion that in this context, telling children about their donor conception both safeguards and promotes their interests, particularly if such disclosure is motivated by parents' anxieties about accidental discovery. Disclosure that is motivated by the notion of non-anonymity may also encourage parents to share misinformation about donors and encourage their children to have unrealistic expectations. Fertility professionals must remain mindful of these outcomes when discussing disclosure and the future implications of increasing access to genetic information with both prospective and current parents. It is strongly advised that future discussions about the end of donor anonymity are not conflated with the debate on disclosure.The Brocher Foundation (Geneva) , Corpus Christi College (Cambridge)This is the author accepted manuscript. The final version is available from Oxford University Press via http://dx.doi.org/10.1093/humrep/dew24
Financial feasibility of end-user designed rainwater harvesting and greywater reuse systems for high water use households
© 2017, The Author(s). Water availability pressures, competing end-uses and sewers at capacity are all drivers for change in urban water management. Rainwater harvesting (RWH) and greywater reuse (GWR) systems constitute alternatives to reduce drinking water usage and in the case of RWH, reduce roof runoff entering sewers. Despite the increasing popularity of installations in commercial buildings, RWH and GWR technologies at a household scale have proved less popular, across a range of global contexts. For systems designed from the top-down, this is often due to the lack of a favourable cost-benefit (where subsidies are unavailable), though few studies have focused on performing full capital and operational financial assessments, particularly in high water consumption households. Using a bottom-up design approach, based on a questionnaire survey with 35 households in a residential complex in Bucaramanga, Colombia, this article considers the initial financial feasibility of three RWH and GWR system configurations proposed for high water using households (equivalent to >203L per capita per day). A full capital and operational financial assessment was performed at a more detailed level for the most viable design using historic rainfall data. For the selected configuration (‘Alt 2’), the estimated potable water saving was 44% (equivalent to 131m3/year) with a rate of return on investment of 6.5% and an estimated payback period of 23years. As an initial end-user-driven design exercise, these results are promising and constitute a starting point for facilitating such approaches to urban water management at the household scale
Population Genetic Differences along a Latitudinal Cline between Original and Recently Colonized Habitat in a Butterfly
BACKGROUND: Past and current range or spatial expansions have important consequences on population genetic structure. Habitat-use expansion, i.e. changing habitat associations, may also influence genetic population parameters, but has been less studied. Here we examined the genetic population structure of a Palaeartic woodland butterfly Pararge aegeria (Nymphalidae) which has recently colonized agricultural landscapes in NW-Europe. Butterflies from woodland and agricultural landscapes differ in several phenotypic traits (including morphology, behavior and life history). We investigated whether phenotypic divergence is accompanied by genetic divergence between populations of different landscapes along a 700 km latitudinal gradient. METHODOLOGY/PRINCIPAL FINDINGS: Populations (23) along the latitudinal gradient in both landscape types were analyzed using microsatellite and allozyme markers. A general decrease in genetic diversity with latitude was detected, likely due to post-glacial colonization effects. Contrary to expectations, agricultural landscapes were not less diverse and no significant bottlenecks were detected. Nonetheless, a genetic signature of recent colonization is reflected in the absence of clinal genetic differentiation within the agricultural landscape, significantly lower gene flow between agricultural populations (3.494) than between woodland populations (4.183), and significantly higher genetic differentiation between agricultural (0.050) than woodland (0.034) pairwise comparisons, likely due to multiple founder events. Globally, the genetic data suggest multiple long distance dispersal/colonization events and subsequent high intra- and inter-landscape gene flow in this species. Phosphoglucomutase deviated from other enzymes and microsatellite markers, and hence may be under selection along the latitudinal gradient but not between landscape types. Phenotypic divergence was greater than genetic divergence, indicating directional selection on some flight morphology traits. MAIN CONCLUSIONS/SIGNIFICANCE: Clinal differentiation characterizes the population structure within the original woodland habitat. Genetic signatures of recent habitat expansion remain, notwithstanding high gene flow. After differentiation through drift was excluded, both latitude and landscape were significant factors inducing spatially variable phenotypic variation
- …