Imaging simulations have been carried out with a version of the spiral zoom array presented in Conway(2000) (Memo 283). Two test images were used, one based on a VLA image of Cygnus A and another based on an OVRO CO map of M51. Both snapshot and long track CLEAN simulations were carried out. The results were compared with those obtained for a single ring array with similar resolution. The singl...

Using Path Integral Monte Carlo, we have calculated exchange frequencies as electrons undergo ring exchanges of 2, 3, and 4 electrons in a “clean” 3D Wigner crystal (bcc lattice) as a function of density. We find pair exchange dominates and estimate the critical temperature for the transition to antiferromagnetic ordering to be roughly 1310−8 Ry at melting. In contrast to the situation in 2D, t...

High current and stringent restrictions on beam losses in the designed linac and storage ring for the Spallation Neutron Source (SNS) require clean and fast – with the rise time from 2% to 98% less than 2.5 ns – beam chopping in the linac front end, at the beam energy 2.5 MeV. The development of new traveling-wave deflecting current structures, based on meander lines, for the SNS fast chopper i...

I begin with the proposition that eating is an agricultural act. Eating ends the annual drama of the food economy that begins with planting and birth. Most eaters, however, are no longer aware that this is true. They think of food as an agricultural product, perhaps, but they do not think of themselves as participants in agriculture. They think of themselves as “consumers.” If they think beyond...

A study is presented of a possible future measurement of the longitudinal structure function FL(x,Q ) with different proton beam energies at HERA. To appear in the proceedings of the workshop “Future Physics at HERA”, DESY, Hamburg, 1996. Future Measurement of the Longitudinal Proton Structure Function at HERA L.A.T. Bauerdick, A. Glazov, M. Klein a DESY, Notkestraße 85, D-22607 Hamburg, German...

Clean and As covered zinc-blende and wurtzite GaN surfaces have been investigated employing density-functional theory calculations. For clean GaN surfaces our calculations indicate the stability of several novel surface structures that are very different from those found on traditional III-V semiconductors. Adding impurities commonly present in significant concentrations during growth strongly ...

In the past few years, the amount of malicious software increased exponentially and, therefore, machine learning algorithms became instrumental in identifying clean and malware files through (semi)-automated classification. When working with very large datasets, the major challenge is to reach both a very high malware detection rate and a very low false positive rate. Another challenge is to mi...

3.1 PRODUCTION OF CLEAN SYNTHESIS GAS......................................................................... 9 3.1.1 Biomass Gasification .............................................................................................. 9 3.1.2 Gas Cleanup.......................................................................................................... 10 3.2 CONVERSION OF SYNTHESIS GAS T...

This paper is intended as a first step in a program for a full algorithmic enumeration of lattice 3-polytopes. The program is based in the following two facts, that we prove: • For each n there is only a finite number of (equivalence classes of) 3polytopes of lattice width larger than one, where n is the number of lattice points. Polytopes of width one are infinitely many, but easy to classify....

Chiral pyrrolidines and pyrrolizidines with spirooxindole ring systems are the central skeletons for numerous alkaloids and pharmacologically important compounds. Gelesmine, pseudotabersonine, formosanine, isoformosanine, morroniside and mitraphylline are some of the alkaloids containing spirooxindole ring systems. Derivatives of spirooxindole find very wide biological applications as anti micr...