599 research outputs found
Two dimensional wedge/translating shroud nozzle
A jet propulsion exhaust nozzle is reported for multi-engine installations which produces high internal/external, thrust-minus-drag, performance for transonic cruise or transonic acceleration as well as improved performance at subsonic and supersonic speeds. A two dimensional wedge/translating shroud provides the variable nozzle exit geometry needed to achieve high engine performance over a wide range of throttle power settings
Performance of twin two-dimensional wedge nozzles including thrust vectoring and reversing effects at speeds up to Mach 2.20
Transonic tunnel and supersonic pressure tunnel tests were reformed to determine the performance characteristics of twin nonaxisymmetric or two-dimensional nozzles with fixed shrouds and variable-geometry wedges. The effects of thrust vectoring, reversing, and installation of various tails were also studied. The investigation was conducted statically and at flight speeds up to a Mach number of 2.20. The total pressure ratio of the simulated jet exhaust was varied up to approximately 26 depending on Mach number. The Reynolds number per meter varied up to 13.20 x 1 million. An analytical study was made to determine the effect on calculated wave drag by varying the mathematical model used to simulate nozzle jet-exhaust plume
Effects of an in-flight thrust reverser on the stability and control characteristics of a single-engine fighter airplane model
The changes in thrust minus drag performance as well as longitudinal and directional stability and control characteristics of a single-engine jet aircraft attributable to an in-flight thrust reverser of the blocker-deflector door type were investigated in a 16-foot transonic wind tunnel. The longitudinal and directional stability data are presented. Test conditions simulated landing approach conditions as well as high speed maneuvering such as may be required for combat or steep descent from high altitude
Performance of an isolated two-dimensional wedge nozzle with fixed cowl and variable wedge centerbody at Mach numbers up to 2.01
A wind tunnel investigation has been conducted to determine the aeropropulsion performance (thrust minus drag) of an isolated, two-dimensional wedge nozzle with a simulated variable-wedge mechanism and a fixed cowl. The investigation was conducted statically and at Mach numbers from 0.60 to 1.20 in the Langley 16-foot transonic tunnel and at a Mach number of 2.01 in the Langley 4-foot supersonic pressure tunnel. The ratio of exhaust jet total pressure to free-stream static pressure was varied up to 27 depending on free-stream Mach number. The results indicate that the aeropropulsion performance of the two-dimensional fixed-cowl variable-wedge nozzle is slightly lower (0.7 to 1.4 percent of ideal thrust) than that achieved for a two-dimensional wedge nozzle with a translating shroud, although part of the difference in performance is attributed to internal-performance differences. The effects of cowl boattail angle, internal expansion area ratio, and wedge half-angle on the performance of the two-dimensional wedge nozzle are discussed
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Digital Creativity Support for Original Journalism
The decline in circulations and revenues resulting from the digitalization of news production and consumption has led to a crisis in journalism.Journalists have less time to research, investigate and write original stories, leading to problems for our democratic processes and holding the powerful to account. This paper reports the architecture, features and rationale for new digital creativity support designed to support journalists to discover more original angles onstories. It also summarises the evaluation of the tool’s use in 3 newsrooms
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Creativity Support in a Serious Game for Dementia Care
This paper advocates the use of computer-based serious games as a form of creativity support tool. Whilst the use of serious games has grown considerably in recent years, support for players to think creatively is often implicit in the game, and does not exploit the wide range of creativity techniques and software tools available. This paper makes the case for explicit creativity support in serious games, explores how implicit creativity support can be delivered in game play, and extends one reported model of serious game play with activities in which players deploy different forms of supported creative thinking. The model is then applied to inform 2 versions of a serious game developed to train carers in creativity techniques to deliver more person-centered care to people with dementia. Each version of the game was delivered as a prototype to support playtesting of the game and its effect on carer training
Examining the Responsibilities of Faculty Senates
Faculty senates function to preserve and represent the interest of the faculty during the decision-making process. The purpose of this article is to initiate dialogue focused on increasing the influence of the faculty senates in an era of declining power
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Evaluating the Use of Digital Creativity Support by Journalists in Newsrooms
This paper reports the evaluation of a new digital support tool designed to increase journalist creativity and productivity in newsrooms. After outlining the tool’s principles, interactive features and architecture, the paper reports the installation and use of the tool over 2 months by 12 journalists in the newsrooms of 3 newspapers. Results from this evaluation revealed that tool use was associated with published news articles rated as more novel but not more valuable than published articles written by the same journalists without the tool. However, tool use did not increase journalist productivity. The evaluation results were used to inform future changes to the digital creativity support tool
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