1,895 research outputs found
A simpler and faster algorithm for optimal total-work-content-power due date determination
Due date determination problems comprise scheduling problems in which not only the scheduling of n jobs is involved, but the assignment of due dates to jobs as well. This paper considers the case where a schedule is given and there is a single decision variable involved: the due date multiplier. The multiplier is used to set the due dates in order to minimize a composite objective function. Recently, an O(n2) algorithm was presented, the validity of which was proved on basis of the dual of the linear programming formulation of this problem. We give a simpler and faster algorithm based upon strictly primal arguments, requiring only O(n log n) time. In addition, we point out that these arguments can be employed for alternative proofs in case of a common due date
Closure on âSimulation of Switched Reluctance Motor Drives Using Two-Dimensional Bicubic Splineâ
Non-renormalization of induced charges and constraints on strongly coupled theories
It is shown that global fermionic charges induced in vacuum by slowly
varying, topologically non-trivial background scalar fields are not
renormalized provided that expansion in momenta of background fields is valid.
This suggests that strongly coupled theories obey induced charge matching
conditions which are analogous, but generally not equivalent, to 't Hooft
anomaly matching conditions. We give a few examples of induced charge matching.
In particular, the corresponding constraints in softly broken supersymmetric
QCD suggest non-trivial low energy mass pattern, in full accord with the
results of direct analyses.Comment: 19 pages, LaTeX, two PS figures; Submitted to special issue of Phys.
Reports dedicated to 70th birthday of L.B.Oku
Dynamics of Gravity in a Higgs Phase
We investigate the universal low-energy dynamics of the simplest Higgs phase
for gravity, `ghost condensation.' We show that the nonlinear dynamics of the
`ghostone' field dominate for all interesting gravitational sources. Away from
caustic singularities, the dynamics is equivalent to the irrotational flow of a
perfect fluid with equation of state p \propto \rho^2, where the fluid
particles can have negative mass. We argue that this theory is free from
catastrophic instabilities due to growing modes, even though the null energy
condition is violated. Numerical simulations show that solutions generally have
singularities in which negative energy regions shrink to zero size. We exhibit
partial UV completions of the theory in which these singularities are smoothly
resolved, so this does not signal any inconsistency in the effective theory. We
also consider the bounds on the symmetry breaking scale M in this theory. We
argue that the nonlinear dynamics cuts off the Jeans instability of the linear
theory, and allows M \lsim 100MeV.Comment: 54 pages, 15 figures; postscript figures downloadable from
http://schwinger.harvard.edu/~wiseman/Ghost/ghostepsfigs.tar.gz ; v2:
substantial revision to section 5 on bound
Generation of Long-Lived Isomeric States via Bremsstrahlung Irradiation
A method to generate long-lived isomeric states effectively for Mossbauer
applications is reported. We demonstrate that this method is better and easier
to provide highly sensitive Mossbauer effect of long-lived isomers (>1ms) such
as 103Rh. Excitation of (gamma,gamma) process by synchrotron radiation is
painful due mainly to their limited linewidth. Instead,(gamma,gamma') process
of bremsstrahlung excitation is applied to create these long-lived isomers.
Isomers of 45Sc, 107Ag, 109Ag, and 103Rh have been generated from this method.
Among them, 103Rh is the only one that we have obtained the gravitational
effect at room temperature.Comment: ICAME 05 conference repor
Leaf Extracts of Calocedrus formosana (Florin) Induce G2/M Cell Cycle Arrest and Apoptosis in Human Bladder Cancer Cells
Calocedrus formosana (Florin) bark acetone/ethylacetate extracts are known to exert an antitumor effect on some human cancer cell lines, but the mechanism is yet to be defined. The aim of this study was to determine the effects of Florin leaf methanol extracts on the growth and apoptosis of human bladder cancer cell lines. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed that the growth of these bladder cancer cells was potently inhibited by the Florin leaf extracts. The cell cycle of these extract-treated cells (TCCSUP cells) was arrested at the G2/M phase as determined by flow cytometry. Western blot analysis revealed the increases of cyclin B1 and Cdc2 kinase levels, alone with the decrease of phosphorylated Cdc2 kinase, after treating these cells with the extracts. An immunofluorescence assessment of ÎČ-tubulin showed decreased levels of polymerized tubulin in treated cells. However, the proteolytic cleavage of poly ADP-ribose polymerase and the activation of caspase-3/-8/-9 were all increased upon treatments of extracts. The concurrent increase of Bax and decrease of Bcl-2 levels indicated that the extracts could induce apoptosis in these treated cells. Taken together, these results suggest that the Florin leaf extracts may be an effective antibladder cancer agent
Theory of coherent acoustic phonons in InGaN/GaN multi-quantum wells
A microscopic theory for the generation and propagation of coherent LA
phonons in pseudomorphically strained wurzite (0001) InGaN/GaN multi-quantum
well (MQW) p-i-n diodes is presented. The generation of coherent LA phonons is
driven by photoexcitation of electron-hole pairs by an ultrafast Gaussian pump
laser and is treated theoretically using the density matrix formalism. We use
realistic wurzite bandstructures taking valence-band mixing and strain-induced
piezo- electric fields into account. In addition, the many-body Coulomb
ineraction is treated in the screened time-dependent Hartree-Fock
approximation. We find that under typical experimental conditions, our
microscopic theory can be simplified and mapped onto a loaded string problem
which can be easily solved.Comment: 20 pages, 17 figure
The Proton Spin and Flavor Structure in the Chiral Quark Model
After a pedagogical review of the simple constituent quark model and deep
inelastic sum rules, we describe how a quark sea as produced by the emission of
internal Goldstone bosons by the valence quarks can account for the observed
features of proton spin and flavor structures. Some issues concerning the
strange quark content of the nucleon are also discussed.Comment: 59 pages with table of contents, Lecture delivered at the Schladming
Winter School (March 1997), to be published by Springer-Verlag under the
title "Computing Particle Properties" (eds. C. B. Lang and H. Gausterer
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