2,267 research outputs found
Turboprop cargo aircraft systems study
The effects of using advanced turboprop propulsion systems to reduce the fuel consumption and direct operating costs of cargo aircraft were studied, and the impact of these systems on aircraft noise and noise prints around a terminal area was determined. Parametric variations of aircraft and propeller characteristics were investigated to determine their effects on noiseprint areas, fuel consumption, and direct operating costs. From these results, three aircraft designs were selected and subjected to design refinements and sensitivity analyses. Three competitive turbofan aircraft were also defined from parametric studies to provide a basis for comparing the two types of propulsion
Turboprop Cargo Aircraft Systems study, phase 1
The effects of advanced propellers (propfan) on aircraft direct operating costs, fuel consumption, and noiseprints were determined. A comparison of three aircraft selected from the results with competitive turbofan aircraft shows that advanced turboprop aircraft offer these potential benefits, relative to advanced turbofan aircraft: 21 percent fuel saving, 26 percent higher fuel efficiency, 15 percent lower DOCs, and 25 percent shorter field lengths. Fuel consumption for the turboprop is nearly 40 percent less than for current commercial turbofan aircraft. Aircraft with both types of propulsion satisfy current federal noise regulations. Advanced turboprop aircraft have smaller noiseprints at 90 EPNdB than advanced turbofan aircraft, but large noiseprints at 70 and 80 EPNdB levels, which are usually suggested as quietness goals. Accelerated development of advanced turboprops is strongly recommended to permit early attainment of the potential fuel saving. Several areas of work are identified which may produce quieter turboprop aircraft
Explanation, prediction, causation ā an unholy trinity? Appreciative comments on Philosophy and Methods in Political Science
In this short
but critical appreciation of Keith Dowdingās seminal
Philosophy and
Methods of Political Science
I reflect on the distinctive treatment of both realism and explanation
in contemporary political science that its author offers, expressing rather more sympath
y for the
former than the latter. I welcome his critique of the use and misuse of āismsā in much of the
existing literature, whilst pointing to some potential inconsistencies; I accept his broad and
inclusive understanding of philosophic realism; and I pr
aise Dowding for putting the question of
explanation
ā
and its adequacy
ā
at the heart of the philosophy of political science (where I think
it belongs). Yet I reject the idea that prediction is or, indeed, should be central to all social
scientific expla
nation. Similarly I take issue with the contention that we are typically distracted
by questions of causation, suggesting that the presentation of a ācredibly causalā narrative is the
crux of adjudicating good from bad explanation. I explore the implicat
ions of such a position and
conclude with comments on Dowdingās call for the reproducibility and transparency of data
Natural Notation for the Domestic Internet of Things
This study explores the use of natural language to give instructions that
might be interpreted by Internet of Things (IoT) devices in a domestic `smart
home' environment. We start from the proposition that reminders can be
considered as a type of end-user programming, in which the executed actions
might be performed either by an automated agent or by the author of the
reminder. We conducted an experiment in which people wrote sticky notes
specifying future actions in their home. In different conditions, these notes
were addressed to themselves, to others, or to a computer agent.We analyse the
linguistic features and strategies that are used to achieve these tasks,
including the use of graphical resources as an informal visual language. The
findings provide a basis for design guidance related to end-user development
for the Internet of Things.Comment: Proceedings of the 5th International symposium on End-User
Development (IS-EUD), Madrid, Spain, May, 201
Circuit Theory and Design
Contains resesarch objectives.Lincoln Laboratory, Purchase Order DDL B-00368U. S. Air Force under Air Force Contract AF19(604)-7400U. S. NavyU. S. Arm
Robot rights? Towards a social-relational justification of moral consideration \ud
Should we grant rights to artificially intelligent robots? Most current and near-future robots do not meet the hard criteria set by deontological and utilitarian theory. Virtue ethics can avoid this problem with its indirect approach. However, both direct and indirect arguments for moral consideration rest on ontological features of entities, an approach which incurs several problems. In response to these difficulties, this paper taps into a different conceptual resource in order to be able to grant some degree of moral consideration to some intelligent social robots: it sketches a novel argument for moral consideration based on social relations. It is shown that to further develop this argument we need to revise our existing ontological and social-political frameworks. It is suggested that we need a social ecology, which may be developed by engaging with Western ecology and Eastern worldviews. Although this relational turn raises many difficult issues and requires more work, this paper provides a rough outline of an alternative approach to moral consideration that can assist us in shaping our relations to intelligent robots and, by extension, to all artificial and biological entities that appear to us as more than instruments for our human purpose
An output-sensitive algorithm for the minimization of 2-dimensional String Covers
String covers are a powerful tool for analyzing the quasi-periodicity of
1-dimensional data and find applications in automata theory, computational
biology, coding and the analysis of transactional data. A \emph{cover} of a
string is a string for which every letter of lies within some
occurrence of . String covers have been generalized in many ways, leading to
\emph{k-covers}, \emph{-covers}, \emph{approximate covers} and were
studied in different contexts such as \emph{indeterminate strings}.
In this paper we generalize string covers to the context of 2-dimensional
data, such as images. We show how they can be used for the extraction of
textures from images and identification of primitive cells in lattice data.
This has interesting applications in image compression, procedural terrain
generation and crystallography
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