127,687 research outputs found
Physics of the Pseudogap State: Spin-Charge Locking
The properties of the pseudogap phase above Tc of the high-Tc cuprate
superconductors are described by showing that the Anderson-Nambu SU(2) spinors
of an RVB spin gap 'lock' to those of the electron charge system because of the
resulting improvement of kinetic energy. This enormously extends the range of
the vortex liquid state in these materials. As a result it is not clear that
the spinons are ever truly deconfined. A heuristic description of the
electrodynamics of this pseudogap-vortex liquid state is proposed.Comment: Submitted to Phys Rev Letter
The Look-point Aircraft Coordinate Estimator (LACE) and potential applications
A look-point aircraft coordinate estimator (LACE) consisting of a windshield runway symbol projector, pilot input controls, microprocessor, and eye-alignment device is described. The estimator is used by a pilot to determine his aircraft's position relative to a runway or other visible terrain or target. The pilot initially superimposes and then corrects the superposition of the runway symbol over the runway during approach during periods when the runway is visible. Using the pilot's inputs the microprocessor calculates the position of the aircraft in terms of runway coordinates, then generates an approach trajectory and issues instructions to an autopilot. The microprocessor contains a model of the aircraft's dynamics and calculates a theoretical aircraft trajectory. The theoretical position of the aircraft is then used to drive the runway symbol, with the pilot's input being additive. The system thus acts as an aid in making low visibility approaches and landings when only an occasional glimpse of the runway is possible and no ground referenced landing systems are available. The system can also be used as an independent landing monitor for ground referenced landing systems
"Absolutely, totally, filled to the brim with the Famous Grouse": intensifying adverbs in the Scottish Corpus of Texts and Speech
The Scottish Corpus of Texts and Speech
(SCOTS for short) has been available online
since November 2004. It currently contains
over 2.3 million words of texts in varieties of
Broad Scots and Scottish English. Regular
additions are made to the textual content of the
corpus and the integrated search and analysis
software is continually undergoing improvement.
Over the next year, the corpus will grow
to around 4 million words, 20% of which will
comprise spoken language in the form of conversations
and interviews
Semiconductor electrolyte photovoltaic energy converter
Feasibility and practicality of a solar cell consisting of a semiconductor surface in contact with an electrolyte are evaluated. Basic components and processes are detailed for photovoltaic energy conversion at the surface of an n-type semiconductor in contact with an electrolyte which is oxidizing to conduction band electrons. Characteristics of single crystal CdS, GaAs, CdSe, CdTe and thin film CdS in contact with aqueous and methanol based electrolytes are studied and open circuit voltages are measured from Mott-Schottky plots and open circuit photo voltages. Quantum efficiencies for short circuit photo currents of a CdS crystal and a 20 micrometer film are shown together with electrical and photovoltaic properties. Highest photon irradiances are observed with the GaAs cell
The SCOTS Corpus: a resource for language contact study
The Scottish Corpus of Texts and Speech (SCOTS) is an ongoing project in the Department of English Language, University of Glasgow. The ultimate aim of the project is to create a large electronic corpus of both written and spoken texts for the languages of Scotland, which will reflect the linguistic situation in current-day Scotland. The corpus will be freely accessible and searchable on the Web.
A corpus such as this of course can have any number of applications: in addition to studies of language contact, corpus methodology makes possible various types of self-contained investigation into the lexis, grammar, phraseology, pragmatics etc., of the languages of Scotland. The aim of this paper is to introduce the corpus, and highlight some of its possible applications in the study of language contact. Contact has been historically important for the languages of Scotland, and this is no less true today: I hope therefore to suggest ways in which the resource will be valuable for such research in the very near future
Magnetic suspension and pointing system
An apparatus is reported for accurate pointing of instruments on a carrier vehicle and for isolation of the instruments from the vehicle's motion disturbances. The apparatus includes two assemblies with connecting interfaces. The first assembly is attached to the carrier vehicle and consists of an azimuth gimbal and an elevation gimbal which provide coarse pointing by allowing two rotations of the instruments relative to the carrier vehicle. The second or vernier pointing assembly is made up of magnetic suspension and fine pointing actuators, roll motor segments, and an instrument mounting plase which provides appropriate magnetic circuits for the actuators and the roll motor segments. The vernier pointing assembly provides attitude fine pointing and roll positioning of the instruments as well as six degree-of-freedom isolation from carrier motion disturbances
Solenoid valve design has one moving part
Solenoid valve structure has only one moving part, a ball and spring assembly. This eliminates wear caused by sliding motion contact between stationary and moving parts or between moving parts
- …