32,572 research outputs found
Method for milling and drilling glass
A process for machining glass by placing a rotating carbide working surface under minimum pressure against an area of glass to be worked is described. Concurrently the region between the working surface and the area of glass is wet with a lubricant consisting essentially of a petroleum carrier, a complex mixture of esters and a complex mixture of naturally occurring aromatic oils
Some expansions associated with Bessel functions
An Expansion for the Product of Two Bessel Functions.-1.1. An expansion for the product of two Bessel functions obtained by one of us(1) led to the discovery of a different expansion for the said product multiplied by the leading terms in the power series for the Bessel functions. Two proofs of this second expansion are given here
Accurate statistics of a flexible polymer chain in shear flow
We present exact and analytically accurate results for the problem of a
flexible polymer chain in shear flow. Under such a flow the polymer tumbles,
and the probability distribution of the tumbling times of the polymer
decays exponentially as (where is the
longest relaxation time). We show that for a Rouse chain, this nontrivial
constant can be calculated in the limit of large Weissenberg number
(high shear rate) and is in excellent agreement with our simulation result of
. We also derive exactly the distribution functions for
the length and the orientational angles of the end-to-end vector of the
polymer.Comment: 4 pages, 2 figures. Minor changes. Texts differ slightly from the PRL
published versio
An interferometer based phase control system
An interferometer based phase control system for focusing and pointing the solar power satellite (SPS) power beam is discussed. The system is ground based and closed loop. One receiving antenna is required on Earth. A conventional uplink data channel transmits an 8 bit phase error correction back to the SPS for sequential calibration of each power module. Beam pointing resolution is better than 140 meters at the rectenna
A power satellite sonic simulator
A simulator is described which generates and transmits a beam of audible sound energy mathematically similar to the solar power satellite (SPS) power beam. The simulator provides a laboratory means for analysis of ground based closed loop SPS phase control and of ionospheric effects on the SPS microwave power beam
A General Method for Complete Population Transfer in Degenerate Systems
A simple theoretical solution to the design of a control field that generates
complete population transfer from an initial state, via nondegenerate
intermediate states, to one arbitrary member of () degenerate
states is constructed. The full control field exploits an -node null
adiabatic state, created by designing the relative phases and amplitudes of the
component fields that together make up the full field. The solution found is
universal in the sense that it does not depend on the exact number of the
unwanted degenerate states or their properties. The results obtained suggest
that a class of multi-level quantum systems with degenerate states can be
completely controllable, even under extremely strong constraints, e.g., never
populating a Hilbert subspace that is only a few dimensions smaller than the
whole Hilbert space.Comment: 12 pages, 5 figures, submitted to Phys. Rev.
A sonic satellite power system microwave power transmission simulation
A simulator is described which generates and transmits a beam of audible sound energy mathematically similar to the SPS power beam. The simulator provides a laboratory means for analysis of ground based closed loop SPS phase control and of ionospheric effects on the SPS microwave power beam
Sonic simulation of the SPS power beam
A Satellite Power System Microwave Transmission Simulator is described. The simulator generates and transmits a beam audible sound energy which is mathematically similar to the microwave beam which would transmit energy to Earth from a Solar Power Satellite. This allows areas such as power beam formation to be studied in a laboratory environment
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