45,394 research outputs found
Polynomiality for Bin Packing with a Constant Number of Item Types
We consider the bin packing problem with d different item sizes s_i and item
multiplicities a_i, where all numbers are given in binary encoding. This
problem formulation is also known as the 1-dimensional cutting stock problem.
In this work, we provide an algorithm which, for constant d, solves bin
packing in polynomial time. This was an open problem for all d >= 3.
In fact, for constant d our algorithm solves the following problem in
polynomial time: given two d-dimensional polytopes P and Q, find the smallest
number of integer points in P whose sum lies in Q.
Our approach also applies to high multiplicity scheduling problems in which
the number of copies of each job type is given in binary encoding and each type
comes with certain parameters such as release dates, processing times and
deadlines. We show that a variety of high multiplicity scheduling problems can
be solved in polynomial time if the number of job types is constant
The Commercial Music Industry in Atlanta and the State of Georgia: An Economic Impact Study
This study was prepared to ascertain the magnitude of the commercial music industry's economic impact on Atlanta and its surrounding areas. Report #8
Comments on lattice gauge theories with infrared-attractive fixed points
Theories of interacting gauge fields and fermions can possess a running gauge
coupling with an infrared attractive fixed point (IRFP). We present a minimal
description of the physics of these systems and comment on some simple
expectations for results from lattice simulations done within the basin of
attraction of the IRFP in these theories.Comment: 10 pages, 2 figures. Published version, fixed typos in version
Combinatorial analysis of interacting RNA molecules
Recently several minimum free energy (MFE) folding algorithms for predicting
the joint structure of two interacting RNA molecules have been proposed. Their
folding targets are interaction structures, that can be represented as diagrams
with two backbones drawn horizontally on top of each other such that (1)
intramolecular and intermolecular bonds are noncrossing and (2) there is no
"zig-zag" configuration. This paper studies joint structures with arc-length at
least four in which both, interior and exterior stack-lengths are at least two
(no isolated arcs). The key idea in this paper is to consider a new type of
shape, based on which joint structures can be derived via symbolic enumeration.
Our results imply simple asymptotic formulas for the number of joint structures
with surprisingly small exponential growth rates. They are of interest in the
context of designing prediction algorithms for RNA-RNA interactions.Comment: 22 pages, 15 figure
Studying Intermediate pT Hadron Production with Fluctuations
Mechanisms for particle production at intermediate pT in nuclear collisions
at RHIC are discussed, emphasizing the differences in associated jet-like
correlations between color-neutral and colored production. An alternative
production mechanism involving both recombination and fragmentation is
suggested, which might simultaneously lead to an enhancement of baryons and to
jet-like correlations. To gain more insight into the relative importance of
different mechanisms a study of constrained distributions of associated
multiplicity is proposed. In a simple model it is shown that these multiplicity
distributions may change significantly, if the nature of the production
mechanism fluctuates from event to event.Comment: 7 pages, 4 figures, talk at Hot Quarks 2004 conferenc
QCD Factorization in Decays into
Based on the QCD factorization approach we analyse the branching ratios for
the channel . From the comparisons with experimental data
provided by CLEO, BELLE and BABAR we constrain the form factor and propose boundaries for this form factor depending on
the CKM matrix element parameters and .Comment: 11 pages, 9 figures. Talk presented at Fourth Tropical Workshop,
Cairns, Australia, 9--13 June 2003. Proceedings to be published by AI
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