1,018 research outputs found

    Britain\u27s Current Economic Policy; the Continued Absence of Strategic Involvement

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    Effect of shaping sensor data on pilot response

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    The pilot of a modern jet aircraft is subjected to varying workloads while being responsible for multiple, ongoing tasks. The ability to associate the pilot's responses with the task/situation, by modifying the way information is presented relative to the task, could provide a means of reducing workload. To examine the feasibility of this concept, a real time simulation study was undertaken to determine whether preprocessing of sensor data would affect pilot response. Results indicated that preprocessing could be an effective way to tailor the pilot's response to displayed data. The effects of three transformations or shaping functions were evaluated with respect to the pilot's ability to predict and detect out-of-tolerance conditions while monitoring an electronic engine display. Two nonlinear transformations, on being the inverse of the other, were compared to a linear transformation. Results indicate that a nonlinear transformation that increases the rate-or-change of output relative to input tends to advance the prediction response and improve the detection response, while a nonlinear transformation that decreases the rate-of-change of output relative to input tends to lengthen the prediction response and make detection more difficult

    Going Green for Less: Cost-Effective Alternative Energy Sources

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    Canadian governments have many renewable energy programs in place to reduce greenhouse gas emissions. But which ones are the most cost-effective use of taxpayers' money? The authors conduct an audit to find out.growth, innovation, renewable energy, GHG emissions

    \u27Nothing but a Pack of Boys:\u27 Preble\u27s Boys and the Culture of Honor in the Early Naval Officer Corps, 1798-1825

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    From the end of the War of 1812 through 1825, the US naval officer corps was plagued by a series of publicized tribunals and duels among its most prestigious officers. These men were members of the first generation of officers to be promoted to the rank of captain (rather than appointed to that rank upon entering the service), and their disputes and disciplinary problems were heavily influenced by the system of honor which dominated the early Navy. This paper analyzes the meaning of honor to the first generation of promoted captains and the role it played in facilitating conflicts between the officers. It will also examine the Navy\u27s responses to these disputes, and the effects of dueling and tribunals on the Navy\u27s reputation with the public

    A Statistical Method of Screening Electrocardiograms

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    Since the advent of the electrocardiogram, usually abbreviated ECG, the extent of its use in the medical field has broadened through research to find extensive applications in the diagnosis of heart ailments. One such application of the electrocardiogram is the diagnosis of the heart\u27s operating condition and classification of its condition into normal and possibly abnormal categories. A new approach to the use of the electrocardiogram to categorize the condition of the heart is described in this thesis. The purpose of this thesis is to present the new method of screening electrocardiograms into normal versus possibly abnormal categories detecting at least fifty percent of the normal electrocardiograms as normal with a maximum number of abnormal electrocardiograms detected abnormal. The results of a feasibility study to determine the effectiveness of the method are also discussed

    The effect of organic farming systems on aspects of the environment - desk study OF0123

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    Key Conclusions 1. The crop rotations of organic systems maintain landscape diversity and biodiversity whilst the maintenance of field boundaries on organic units produces benefits to a wide range of organisms. 2. Inorganic nitrogen fertilisation and herbicide treatments of conventionally managed grassland has reduced the floral diversity of permanent pastures and maintained the low diversity of re-seeded pastures, greatly reducing their value as wildlife habitats. 3. Pesticide use is responsible for the removal of food sourcesfor birds and mammals in the form of weeds and invertebrates, as well as removing whole populations of potentially beneficial insects. 4. The majority of water pollution incidents from farms are caused during storage and spreading of cattle and pig slurries. A higher proportion of organic cattle and virtually all organic pigs are kept on solid manure systems and therefore are les of a risk. 5. The nitrogen balance of individual 'conventional' and 'organic' systems will depend greatly on the circumstances and management practices of the individual farms. Consequently it is not possible to generalise that one system is always better than the other in terms of nitrate leaching risk. With this qualification the literature does indicate that generally, organic systems offer less risk of nitrate leaching. 6. Organic systems are less likely to cause loss of phosphate into surface and ground waters. Both leaching and loss in eroded soil are likely to be reduced. 7. Organic management practicess such as rotations, the regular use of manures and non-use of pesticides usually increase soil organic matter contents. 8. Organic practices are likely to increase earthworm numbers compared to conventional systems. The increased numbers are universally acknowledged to benefit soil fertility although such effects are difficult to quantify. 9. Soil erosion is less of a problem on organic units. 10. Accumulations of copper and zinc in soils are much reduced in organic systems because organic pig and poultry producers do not supplement feeds with these metals as growth promoters. Copper fungicides are more widely used on organic farms and their use should be carefully monitored to prevent harmful effects. 11. The practices adopted by organic farmers can reduce emissions of nitrous oxide and methane. Ammonia emissions will not necessarily be less in organic than in conventional farming. 12. Organic farmers adopt practices which benefit the landscape. They maintain and introduce features largely because they are required by the Organic Standards to do so. They introduce such management practices because they are technically necessary for successful organic production

    NASA Langley's AirSTAR Testbed: A Subscale Flight Test Capability for Flight Dynamics and Control System Experiments

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    As part of the Airborne Subscale Transport Aircraft Research (AirSTAR) project, NASA Langley Research Center (LaRC) has developed a subscaled flying testbed in order to conduct research experiments in support of the goals of NASA s Aviation Safety Program. This research capability consists of three distinct components. The first of these is the research aircraft, of which there are several in the AirSTAR stable. These aircraft range from a dynamically-scaled, twin turbine vehicle to a propeller driven, off-the-shelf airframe. Each of these airframes carves out its own niche in the research test program. All of the airplanes have sophisticated on-board data acquisition and actuation systems, recording, telemetering, processing, and/or receiving data from research control systems. The second piece of the testbed is the ground facilities, which encompass the hardware and software infrastructure necessary to provide comprehensive support services for conducting flight research using the subscale aircraft, including: subsystem development, integrated testing, remote piloting of the subscale aircraft, telemetry processing, experimental flight control law implementation and evaluation, flight simulation, data recording/archiving, and communications. The ground facilities are comprised of two major components: (1) The Base Research Station (BRS), a LaRC laboratory facility for system development, testing and data analysis, and (2) The Mobile Operations Station (MOS), a self-contained, motorized vehicle serving as a mobile research command/operations center, functionally equivalent to the BRS, capable of deployment to remote sites for supporting flight tests. The third piece of the testbed is the test facility itself. Research flights carried out by the AirSTAR team are conducted at NASA Wallops Flight Facility (WFF) on the Eastern Shore of Virginia. The UAV Island runway is a 50 x 1500 paved runway that lies within restricted airspace at Wallops Flight Facility. The facility provides all the necessary infrastructure to conduct the research flights in a safe and efficient manner. This paper gives a comprehensive overview of the development of the AirSTAR testbed

    Development of a multi-directional manoeuvre for unified handling qualities investigation

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    A slalom and alignment tracking manoeuvre was developed for multi-directional handling qualities analysis of large transport aircraft in simulation environments. The manoeuvre is defined and scaled as a function of aircraft characteristics, flight conditions using a simple set of mathematical models. Throughout the manoeuvre, the trajectory and overall performances are monitored at a set of gross position and alignment control checkpoints methodically distributed and sized to buoy the task and allow handling qualities analysis based on Cooper Harper Ratings and quantitative data analysis. Initial tests have shown that the manoeuvre sizing method led to feasible manoeuvres at multiple points of the flight envelope of a large civil transport aircraft. The manoeuvre capability to highlight desirable and undesirable handling qualities was also highlighted based on the initial findings for a couple of commercial large transport aircraft, a high aspect ratio wing and in-flight folding wingtip aircraft concepts. The relevance and applicability of the manoeuvre for multi-directional studies are discussed and compared against a more conventional offset landing manoeuvre. Finally, the potential use of the manoeuvre for different aircraft type and test flight is also suggested based on augmented reality technology
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