22,173 research outputs found
Sets of Minimal Capacity and Extremal Domains
Let f be a function meromorphic in a neighborhood of infinity. The central
problem in the present investigation is to find the largest domain D \subset C
to which the function f can be extended in a meromorphic and singlevalued
manner. 'Large' means here that the complement C\D is minimal with respect to
(logarithmic) capacity. Such extremal domains play an important role in Pad'e
approximation. In the paper a unique existence theorem for extremal domains and
their complementary sets of minimal capacity is proved. The topological
structure of sets of minimal capacity is studied, and analytic tools for their
characterization are presented; most notable are here quadratic differentials
and a specific symmetry property of the Green function in the extremal domain.
A local condition for the minimality of the capacity is formulated and studied.
Geometric estimates for sets of minimal capacity are given. Basic ideas are
illustrated by several concrete examples, which are also used in a discussion
of the principal differences between the extremality problem under
investigation and some classical problems from geometric function theory that
possess many similarities, which for instance is the case for Chebotarev's
Problem
Testimony of Herbert R. Northrup Before the Commission on the Future of Worker-Management Relations
Testimony_Northrup_090894.pdf: 378 downloads, before Oct. 1, 2020
Electro-optical spin measurement system
An electro-optical spin measurement system for a spin model in a spin tunnel includes a radio controlled receiver/transmitter, targets located on the spin model, optical receivers mounted around the perimeter of the spin tunnel and the base of the spin tunnel for receiving data from the targets, and a control system for accumulating data from the radio controlled receiver and receivers. Six targets are employed. The spin model includes a fuselage, wings, nose, and tail. Two targets are located under the fuselage of the spin model at the nose tip and tail. Two targets are located on the side of the fuselage at the nose tip and tail, and a target is located under each wing tip. The targets under the fuselage at the nose tip and tail measure spin rate of the spin model, targets on the side of the fuselage at the nose tip and tail measure angle of attack of the spin model, and the targets under the wing tips measure roll angle of the spin model. Optical receivers are mounted at 90 degree increments around the periphery of the spin tunnel to determine angle of attack and roll angle measurements of the spin model. Optical receivers are also mounted at the base of the spin tunnel to define quadrant and position of the spin model and to determine the spin rate of the spin model
Miniaturization of flight deflection measurement system
A flight deflection measurement system is disclosed including a hybrid microchip of a receiver/decoder. The hybrid microchip decoder is mounted piggy back on the miniaturized receiver and forms an integral unit therewith. The flight deflection measurement system employing the miniaturized receiver/decoder can be used in a wind tunnel. In particular, the miniaturized receiver/decoder can be employed in a spin measurement system due to its small size and can retain already established control surface actuation functions
Driving and latching of the Starlab pointing mirror doors
The Starlab Experiment, a major SDIO technology initiative, is an attached payload which will be delivered into Earth orbit aboard NASA's Space Shuttle in 1991. Starlab will generate and aim an 80 cm diameter laser beam into space through a large opening in the structure which houses the pointing mirror. Two doors, each somewhat larger than a desktop, cover the opening when the laser optics system is nonoperational. Latch Mechanism Assemblies hold the doors shut during liftoff and ascent and, again, during Orbiter reentry. Each door is powered by a Door Drive System during the many open/close cycles between various experiments. The design, testing, and resultant failure modes of these mechanisms are examined
CAMMD: Context Aware Mobile Medical Devices
Telemedicine applications on a medical practitioners mobile device should be context-aware. This can vastly improve the effectiveness of mobile applications and is a step towards realising the vision of a ubiquitous telemedicine environment. The nomadic nature of a medical practitioner emphasises location, activity and time as key context-aware elements. An intelligent middleware is needed to effectively interpret and exploit these contextual elements. This paper proposes an agent-based architectural solution called Context-Aware Mobile Medical Devices (CAMMD). This framework can proactively communicate patient records to a portable device based upon the active context of its medical practitioner. An expert system is utilised to cross-reference the context-aware data of location and time against a practitioners work schedule. This proactive distribution of medical data enhances the usability and portability of mobile medical devices. The proposed methodology alleviates constraints on memory storage and enhances user interaction with the handheld device. The framework also improves utilisation of network bandwidth resources. An experimental prototype is presented highlighting the potential of this approach
On the Optimality of Functionals over Triangulations of Delaunay Sets
In this short paper, we consider the functional density on sets of uniformly
bounded triangulations with fixed sets of vertices. We prove that if a
functional attains its minimum on the Delaunay triangulation, for every finite
set in the plane, then for infinite sets the density of this functional attains
its minimum also on the Delaunay triangulations
The light baryon spectrum in a relativistic quark model with instanton-induced quark forces I. The non-strange baryon spectrum and ground-states
This is the second of a series of three papers treating light baryon
resonances up to 3 GeV within a relativistically covariant quark model based on
the three-fermion Bethe-Salpeter equation with instantaneous two- and
three-body forces. In this paper we apply the covariant Salpeter framework
(which we developed in the first paper) to specific quark model calculations.
Quark confinement is realized by a linearly rising three-body string potential
with appropriate spinorial structures in Dirac-space. To describe the hyperfine
structure of the baryon spectrum we adopt 't Hooft's residual interaction based
on QCD-instanton effects and demonstrate that the alternative
one-gluon-exchange is disfavored phenomenological grounds. Our fully
relativistic framework allows to investigate the effects of the full Dirac
structures of residual and confinement forces on the structure of the mass
spectrum. In the present paper we present a detailed analysis of the complete
non-strange baryon spectrum and show that several prominent features of the
nucleon spectrum such as e.g. the Roper resonance and approximate ''parity
doublets'' can be uniformly explained due to a specific interplay of
relativistic effects, the confinement potential and 't Hooft's force. The
results for the spectrum of strange baryons will be discussed in a subsequent
paper.Comment: 59 p. postscript, including 24 figures and 25 tables, submitted to
Eur.Phys.J.
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