17,124 research outputs found
A safety margin and flight reference system and display for powered-lift aircraft
A study was conducted to explore the feasibility of a safety margin and flight reference system for those powered-lift aircraft which require a backside piloting technique. The main objective was to display multiple safety margin criteria as a single variable which could be tracked both manually and automatically and which could be monitored in order to derive safety margin status. The study involved a pilot-in-the-loop analysis of several system concepts and a simulator experiment to evaluate those concepts showing promise. A system was ultimately configured which yielded reasonable compromises in controllability, status information content, and the ability to regulate safety margins at some expense of the allowable low speed flight path envelope
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What do others think is the point of design and technology education?
As a result of a national curriculum review in England (Department for Education [DfE], 2011), a new curriculum for design and technology (D&T) is being taught in secondary schools from September 2014 (Department of Education [DoE], 2013a). This curriculum is compulsory for a decreasing number of schools; two potential consequences are the nature of D&T in secondary schools changing to reflect local perceptions of the subject and maybe D&T being removed from the curriculum completely. The pressure on D&T’s curriculum content is likely to come from different stakeholders such as senior school leaders, D&T teachers, and pupils. D&T school departments could respond to this pressure by adapting the curriculum to popularise the subject or produce high exam results with a consequence that much of the subject’s value is lost. This paper reports on a small research project conducted in two secondary schools where stakeholder representatives were interviewed to identify their values of D&T. These different stakeholders were interviewed using the active interview method (Holstein & Gubrium, 1995), coded following Aurebach and Silverstein’s method (2003) and their values compared to Hardy’s values framework (Hardy, 2013b). Analysis shows most stakeholders believe a key value of D&T is to provide ‘practical life skills’ (Hardy, p.226), whilst only one recognizes that learning in D&T involves ‘identifying problems to be solved’. The outcomes from the research are being used to support critically reflective conversations within both D&T departments (Zwozdiak-Myers, 2012) framing their evaluation of their local curriculum and making changes to their curriculum
probing the atmosphere with high power, high resolution radars
Observations of radar echoes from the clear atmosphere are presented and the scattering mechanisms responsible for the two basic types of clear-air echoes are discussed. The commonly observed dot echo originates from a point in space and usually shows little variation in echo intensity over periods of about 0.1 second. The second type of clear-air radar echo appears diffuse in space, and signal intensities vary considerably over periods of less than 0.1 second. The echoes often occur in thin horizontal layers or as boundaries of convective activity; these are characterized by sharp gradients of refractive index. Some features of clear-air atmospheric structures as observed with radar are presented. These structures include thin stable inversions, convective thermals, Benard convection cells, breaking gravity waves, and high tropospheric layers which are sufficiently turbulent to affect aircraft
Management of Phytophthora cinnamomi for biodiversity conservation in Australia: Part 2. National best practice guidelines
Disease in natural ecosystems of Australia, caused by the introduced plant pathogen Phytophthora cinnamomi, is listed as a key threatening process under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). The Act requires the Australian Government to prepare and implement a threat abatement plan for nationally coordinated action to mitigate the harm caused by P. cinnamomi to Australian species, particularly threatened flora, fauna and ecological communities. The .National Threat Abatement Plan for Dieback Caused by the Root-Rot Fungus Phytophthora cinnamomi. (NTAP) was released in 2001 (Environment Australia, 2001). The NTAP is designed to promote a common understanding of the national threat P. cinnamomi poses to biodiversity in Australia.
This project, funded by the Australian Government Department of the Environment and Heritage (DEH), is one of the most significant actions to be implemented from the NTAP to date. The project has two major components:
* to review current management approaches and identify benchmarks for best practice
* the development of risk assessment criteria and a system for prioritising management of assets that are or could be threatened by P. cinnamomi.
The project outputs are presented in a four-part document entitled Management of Phytophthora cinnamomi for Biodiversity Conservation in Australia:
Part 1 - A Review of Current Management
Part 2 - National Best Practice Guidelines
Part 3 - Risk Assessment for Threats to Ecosystems, Species and Communities: A Review
Part 4 - Risk Assessment Models for Species, Ecological Communities and Areas.
A model of best practice was developed which encompasses all the components necessary for an informed and integrated approach to P. cinnamomi management, from strategic through to on-ground management. The current document (Part 1 . A Review of Current Management) thoroughly reviews the approaches to P. cinnamomi management in Australia within the context of the best practice model
Upgraded demonstration vehicle task report
Vehicle/battery performance capabilities and interface problems that occurred when upgraded developmental batteries were integrated with upgraded versions of comercially available electric vehicles were investigated. Developmental batteries used included nickel zinc batteries, a nickel iron battery, and an improved lead acid battery. Testing of the electric vehicles and upgraded batteries was performed in the complete vehicle system environment to characterize performance and identify problems unique to the vehicle/battery system. Constant speed tests and driving schedule range tests were performed on a chassis dynamometer. The results from these tests of the upgraded batteries and vehicles were compared to performance capabilities for the same vehicles equipped with standard batteries
Electric propulsion options for the SP-100 reference mission
Analyses were performed to characterize and compare electric propulsion systems for use on a space flight demonstration of the SP-100 nuclear power system. The component masses of resistojet, arcjet, and ion thruster systems were calculated using consistent assumptions and the maximum total impulse, velocity increment, and thrusting time were determined, subject to the constraint of the lift capability of a single Space Shuttle launch. From the study it was found that for most systems the propulsion system dry mass was less than 20 percent of the available mass for the propulsion system. The maximum velocity increment was found to be up to 2890 m/sec for resistojet, 3760 m/sec for arcjet, and 23 000 m/sec for ion thruster systems. The maximum thruster time was found to be 19, 47, and 853 days for resistojet, arcjet, and ion thruster systems, respectively
Arianism Revised: The Re-emergence of an Infamous Heresy
Arian heresy, a Trinitarian heresy that suggests the members of the Trinity differ in essence, function, and rank, has existed in Christianity for centuries but hasn\u27t often recaptured the mainstream discussion of orthodoxy. That is, until the 1970s. Since then, the available literature surrounding the subjects of complementarianism, eternal subordination, the Holy Trinity, and Arian philosophy has grown, and the overlap between these factors cumulated into what was arguably one of the most divisive theological debates within modern Evangelicalism. What factors contributed to the reemergence of this centuries-long debate in modern times? The overarching goal of this work is to investigate Arianism’s origins, outline the crucial events that contributed to this religious shift, and propose possible theories for why this shift happened when it did. When the latter objectives are accomplished, readers can perceive the Arian reemergence not as a blip in religious history, but instead, a methodical chain of events that reveals certain instabilities within Evangelical Christianity. The re-emergence of Arian heresy can be largely attributed to the lax doctrinal structure of American Evangelicalism since its origins in the late nineteenth century, which cumulated in the reconsideration of Arian ideas as theologians scrambled to find adequate theological backing for women’s subordination in the face of the Women’s Movement
Bridging the Literature Gap with Age-Appropriate Writing for Middle School Boys and their Teachers
Current research suggests that middle school aged boys are not involved in reading as much as middle school aged girls. Researchers have identified several reasons behind the findings. The first possible reason is a lack of reading interest from boys. The second possible reason is a lack of age appropriate material targeted toward the interests of boys. The third possible reason is an influx of gender-neutral reading material. This project attempts to bridge the gap by providing middle school boys with an age appropriate manuscript. The project also includes a classroom guide which provides teachers with ideas and reproducible materials
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