19,163 research outputs found
Tire/wheel concept
A tire and wheel assembly is disclosed in which a low profile pneumatic tire (having sidewalls which deflect inwardly under load) and a wheel (having a rim featuring a narrow central channel and extended rim flanges) form the combination. The extended rim flanges support the tire sidewalls under static and dynamic loading conditions to produce a combination particularly suited to aircraft applications
MUSE CSP: An Extension to the Constraint Satisfaction Problem
This paper describes an extension to the constraint satisfaction problem
(CSP) called MUSE CSP (MUltiply SEgmented Constraint Satisfaction Problem).
This extension is especially useful for those problems which segment into
multiple sets of partially shared variables. Such problems arise naturally in
signal processing applications including computer vision, speech processing,
and handwriting recognition. For these applications, it is often difficult to
segment the data in only one way given the low-level information utilized by
the segmentation algorithms. MUSE CSP can be used to compactly represent
several similar instances of the constraint satisfaction problem. If multiple
instances of a CSP have some common variables which have the same domains and
constraints, then they can be combined into a single instance of a MUSE CSP,
reducing the work required to apply the constraints. We introduce the concepts
of MUSE node consistency, MUSE arc consistency, and MUSE path consistency. We
then demonstrate how MUSE CSP can be used to compactly represent lexically
ambiguous sentences and the multiple sentence hypotheses that are often
generated by speech recognition algorithms so that grammar constraints can be
used to provide parses for all syntactically correct sentences. Algorithms for
MUSE arc and path consistency are provided. Finally, we discuss how to create a
MUSE CSP from a set of CSPs which are labeled to indicate when the same
variable is shared by more than a single CSP.Comment: See http://www.jair.org/ for any accompanying file
Method of studying the Bogoliubov-de Gennes equations for the superconducting vortex lattice state
In this paper, we present a method to construct the eigenspace of the
normal-state electrons moving in a 2D square lattice in presence of a
perpendicular uniform magnetic field which imposes (quasi)-periodic boundary
conditions for the wave functions in the magnetic unit cell. An exact unitary
transformations are put forward to correlate the discrete eigenvectors of the
2D electrons with those of the Harper's equation. The cyclic-tridiagonal matrix
associated with the Harper's equation is then tridiagonalized by another
unitary transformation. The obtained eigenbasis is utilized to expand the
Bogoliubov-de Gennes equations for the superconducting vortex lattice state,
which showing the merit of our method in studying the large-sized system. To
test our method, we have applied our results to study the vortex lattice state
of an s-wave superconductor.Comment: 8 pages; 3 figure
Low-profile landing-gear assembly
Assembly of cylinders, links, actuators, and gears permits landing-gear unit to be retracted into shadow of main engine intake ducts of supersonic transport aircraft. This is accomplished without adding to frontal area of aircraft or appreciably increasing total aircraft drag
Effects of Electron Correlations on Hofstadter Spectrum
By allowing interactions between electrons, a new Harper's equation is
derived to examine the effects of electron correlations on the Hofstadter
energy spectra. It is shown that the structure of the Hofstadter butterfly ofr
the system of correlated electrons is modified only in the band gaps and the
band widths, but not in the characteristics of self-similarity and the Cantor
set.Comment: 13 pages, 5 Postscript figure
Dependent Types for Pragmatics
This paper proposes the use of dependent types for pragmatic phenomena such
as pronoun binding and presupposition resolution as a type-theoretic
alternative to formalisms such as Discourse Representation Theory and Dynamic
Semantics.Comment: This version updates the paper for publication in LEU
Beyond Search: A Technology Probe Investigation
Purpose — We assert that researchers developing new web interaction tools should consider an array of user motives beyond query-based information retrieval. This chapter reports on two probes used to investigate user activities that go beyond search as traditionally conceived.
Design/methodology — This chapter reviews research on user experiences with search engines and general web use. It then describes the design and case study of cards and pebbles, two search engine-based probes developed to help elicit new concepts for web-based experiences.
Findings — Participants reflect on their experiences with the probes and offer ideas regarding how to incrementally shift the traditional search paradigm and conceive of the web in new ways.
Implications/value — This investigation serves as a starting point by offering criteria that should be considered when designing new ‘beyond search’ tools
Local dissipation effects in two-dimensional quantum Josephson junction arrays with magnetic field
We study the quantum phase transitions in two-dimensional arrays of
Josephson-couples junctions with short range Josephson couplings (given by the
Josephson energy) and the charging energy. We map the problem onto the solvable
quantum generalization of the spherical model that improves over the mean-field
theory method. The arrays are placed on the top of a two-dimensional electron
gas separated by an insulator. We include effects of the local dissipation in
the presence of an external magnetic flux f in square lattice for several
rational fluxes f=0,1/2,1/3,1/4 and 1/6. We also have examined the T=0
superconducting-insulator phase boundary as function of a dissipation alpha for
two different geometry of the lattice: square and triangular. We have found
critical value of the dissipation parameter independent on geometry of the
lattice and presence magnetic field.Comment: accepted to PR
Ocean acidification may alter predator-prey relationships and weaken nonlethal interactions between gastropods and crabs
Predator–prey interactions often drive ecological patterns and are governed by factors including predator feeding rates, prey behavioral avoidance, and prey structural defenses. Invasive species can also play a large ecological role by disrupting food webs, driving local extinctions, and influencing evolutionary changes in prey defense mechanisms. This study documents a
substantial reduction in the behavioral and morphological responses of multiple gastropod species (Nucella lapillus, N. ostrina, Urosalpinx cinerea) to an invasive predatory crab (green crab Carcinus maenas) under ocean acidification conditions. These results suggest that climate-related
changes in ocean chemistry may diminish non-lethal effects of predators on prey responses including behavioral avoidance. While snails with varying shell mineralogies were similarly successful at deterring predation, those with primarily aragonitic shells were more susceptible to dissolution and erosion under high CO2 conditions. The varying susceptibility to predation among species with similar ecological roles could indicate that the impacts of invasive species like green
crabs could be modulated by the ability of native and invasive prey to withstand ocean acidification conditions
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