Sciweavers

COMGEO
2007
ACM
14 years 13 days ago
Graph drawings with few slopes
The slope-number of a graph G is the minimum number of distinct edge slopes in a straight-line drawing of G in the plane. We prove that for Δ 5 and all large n, there is a Δ-reg...
Vida Dujmovic, Matthew Suderman, David R. Wood
IJCGA
2006
85views more  IJCGA 2006»
14 years 13 days ago
Some Lower Bounds on Geometric Separability Problems
We obtain lower bounds in the algebraic computation tree model for deciding the separability of two disjoint point sets. In particular, we show (n log n) time lower bounds for sep...
Esther M. Arkin, Ferran Hurtado, Joseph S. B. Mitc...
IPL
2008
95views more  IPL 2008»
14 years 13 days ago
Distortion lower bounds for line embeddings
In this paper, we show how we can derive lower bounds and also compute the exact distortion for the line embeddings of some special metrics, especially trees and graphs with certai...
Claire Mathieu, Charalampos Papamanthou
BMCBI
2007
153views more  BMCBI 2007»
14 years 13 days ago
Lower bounds on multiple sequence alignment using exact 3-way alignment
Background: Multiple sequence alignment is fundamental. Exponential growth in computation time appears to be inevitable when an optimal alignment is required for many sequences. E...
Charles J. Colbourn, Sudhir Kumar
DC
2006
14 years 14 days ago
On the inherent weakness of conditional primitives
Some well-known primitive operations, such as compare-and-swap, can be used, together with read and write, to implement any object in a wait-free manner. However, this paper shows ...
Faith Ellen Fich, Danny Hendler, Nir Shavit
CORR
2006
Springer
78views Education» more  CORR 2006»
14 years 14 days ago
On the Fading Number of Multiple-Input Single-Output Fading Channels with Memory
We derive new upper and lower bounds on the fading number of multiple-input single-output (MISO) fading channels of general (not necessarily Gaussian) regular law with spatial and ...
Stefan M. Moser
COMBINATORICS
2006
105views more  COMBINATORICS 2006»
14 years 14 days ago
Sets of Points Determining Only Acute Angles and Some Related Colouring Problems
We present both probabilistic and constructive lower bounds on the maximum size of a set of points S Rd such that every angle determined by three points in S is acute, considerin...
David Bevan
CC
2006
Springer
101views System Software» more  CC 2006»
14 years 14 days ago
Inductive Time-Space Lower Bounds for Sat and Related Problems
We improve upon indirect diagonalization arguments for lower bounds on explicit problems within the polynomial hierarchy. Our contributions are summarized as follows.
Ryan Williams
CC
2006
Springer
125views System Software» more  CC 2006»
14 years 14 days ago
A tight lower bound for restricted pir protocols
We show that any 1-round 2-server Private Information Retrieval Protocol where the answers are 1-bit long must ask questions that are at least n - 2 bits long, which is nearly equa...
Richard Beigel, Lance Fortnow, William I. Gasarch
EOR
2008
75views more  EOR 2008»
14 years 15 days ago
Soft car sequencing with colors: Lower bounds and optimality proofs
This paper is a study of the car sequencing problem, when feature spacing constraints are soft and colors of vehicles are taken into account. Both pseudo-polynomial algorithms and ...
Thierry Benoist