An Adaptive Threshold Soft-Limiting UWB Receiver with Improved Performance in Multiuser Interference

Optimum performance in electron and ion imaging instruments, such as electron microscopes and probe-forming instruments, in most cases depends on a compromise either between imaging errors due to spherical and chromatic aberrations and the diffraction error or between the imaging errors and the current in the image. These compromises result in the use of very small angular apertures. Reducing the spherical and chromatic aberration coefficients would permit the use of larger apertures with resulting improved performance, granted that other problems such as incorrect operation of the instrument or spurious disturbances do not interfere. One approach to correcting aberrations which has been investigated extensively is through the use of multipole electric and magnetic fields. Another approach involves the use of foil windows. However, a practical system for correcting spherical and chromatic aberration is not yet available.Our approach to correction of spherical and chromatic aberration makes use of an electrostatic electron mirror. Early studies of the properties of electron mirrors were done by Recknagel. More recently my colleagues and I have studied the properties of the hyperbolic electron mirror as a function of the ratio of accelerating voltage to mirror voltage. The spherical and chromatic aberration coefficients of the mirror are of opposite sign (overcorrected) from those of electron lenses (undercorrected). This important property invites one to find a way to incorporate a correcting mirror in an electron microscope. Unfortunately, the parts of the beam heading toward and away from the mirror must be separated. A transverse magnetic field can separate the beams, but in general the deflection aberrations degrade the image. The key to avoiding the detrimental effects of deflection aberrations is to have deflections take place at image planes. Our separating system is shown in Fig. 1. Deflections take place at the separating magnet and also at two additional magnetic deflectors. The uncorrected magnified image formed by the objective lens is focused in the first deflector, and relay lenses transfer the image to the separating magnet. The interface lens and the hyperbolic mirror acting in zoom fashion return the corrected image to the separating magnet, and the second set of relay lenses transfers the image to the final deflector, where the beam is deflected onto the projection axis.

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Control and Anticipation of Social Interruptions: Reduced Stress, Improved Performance

PsycEXTRA Dataset ◽

10.1037/e518572013-276 ◽

2006 ◽

Author(s):

Drew Carton ◽

John R. Aiello

Keyword(s):

Improved Performance

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Chemotherapy: Improved packaging, improved performance

Nature China ◽

10.1038/nchina.2008.25 ◽

2008 ◽

Author(s):

Jasmine Farsarakis

Keyword(s):

Improved Performance

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Bleaching optimization at WestRock mill in Covington, Virginia

TAPPI Journal ◽

10.32964/tj15.9.581 ◽

2016 ◽

Vol 15 (9) ◽

pp. 581-586 ◽

Cited By ~ 1

Author(s):

RICARDO B. SANTOS ◽

PETER W. HART ◽

DOUGLAS C. PRYKE ◽

JOHN VANDERHEIDE

Keyword(s):

Hydrogen Peroxide ◽

Sodium Hydroxide ◽

Chlorine Dioxide ◽

Capital Expenditures ◽

Equipment Repair ◽

Optimization Program ◽

Hardwood Pulp ◽

Improved Performance

The WestRock mill in Covington, VA, USA, initiated a long term diagnostic and optimization program for all three of its bleaching lines. Benchmarking studies were used to help identify optimization opportunities. Capital expenditures for mixing improvement, filtrate changes, equipment repair, other equipment changes, and species changes were outside the scope of this work. This focus of this paper is the B line, producing southern hardwood pulp in a D(EP)DD sequence at 88% GE brightness. The benchmarking study and optimization work identified the following opportunities for improved performance: nonoptimal addition of caustic and hydrogen peroxide to the (EP) stage, carryover of D0 filtrate to the (EP) stage, and carryover of (EP) filtrate to the D1 stage. As a result of actions the mill undertook to address these opportunities, D0 kappa factor decreased about 5%, sodium hydroxide consumption in the (EP) stage decreased about 35%, chlorine dioxide consumption in the D1 stage decreased about 25%, and overall bleaching cost decreased about 15%.

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