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Search Publications by: James F. Lawrence (Fed)

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Displaying 1 - 23 of 23

Partial Elastic Shape Registration of 3D Surfaces using Dynamic Programming

November 3, 2023
Author(s)
Javier Bernal, James F. Lawrence
The computation of the elastic shape registration of two simple surfaces in 3−dimensional space and therefore of the elastic shape distance between them has been investigated by Kurtek, Jermyn, et al. who have proposed algorithms to carry out this

On Computing Elastic Shape Distances between Curves in d-dimensional Space

June 21, 2021
Author(s)
Javier Bernal, James F. Lawrence, Gunay Dogan, Robert Hagwood
The computation of the elastic registration of two simple curves in higher dimensions and therefore of the elastic shape distance between them has been investigated by Srivastava et al. Assuming the first curve has one or more starting points, and the

Characterization and Computation of Matrices of Maximal Trace over Rotations

October 19, 2019
Author(s)
Javier Bernal, James F. Lawrence
The constrained orthogonal Procrustes problem is the least-squares problem that calls for a rotation matrix that optimally aligns two corresponding sets of points in d-dimensional Euclidean space. This problem generalizes to the so-called Wahba's problem

A Purely Algebraic Justification of the Kabsch-Umeyama Algorithm

October 9, 2019
Author(s)
James F. Lawrence, Javier Bernal, Christoph J. Witzgall
The constrained orthogonal Procrustes problem is the least-squares problem that calls for a rotation matrix that optimally aligns two matrices of the same order. Over past decades, the algorithm of choice for solving this problem has been the Kabsch

The odd-even invariant and Hamiltonian circuits in tope graphs

October 27, 2017
Author(s)
Yvonne Kemper, James F. Lawrence
Questions of the existence of Hamiltonian circuits in the tope graphs of central arrangements of hyperplanes are considered. Connections between the existence of Hamiltonian circuits in the arrangement and the odd-even invariant of the arrangement are

Using Combinatorial Testing to Build Navigation Graphs for Dynamic Web Applications

February 2, 2016
Author(s)
Wenhua Wang, Sreedevi Sampath, Yu Lei, Raghu N. Kacker, D. Richard Kuhn, James F. Lawrence
Modelling a software system is often a challenging prerequisite to automatic test case generation. Modelling the navigation structure of a dynamic web application is particularly challenging because of the presence of a large number of pages that are

Combinatorial Analysis of Diagonal, Box and Greater-Than Polynomials as Packing Functions

November 1, 2015
Author(s)
Pepe Torres Jimenez, Nelson Rangel-Valdez, Raghu N. Kacker, James F. Lawrence
Packing functions (PFs) are bijections between a set of m-dimensional vectors V over N m and nonnegative integers N. PFs have several applications, e.g. in partitioning schemes or text compression. Two important categories of PFs are diagonal polynomials

Obtaining a Trapezoidal Distribution

March 9, 2015
Author(s)
James F. Lawrence, Raghu N. Kacker, Ruediger Kessel
Given a most believed value for a quantity together with upper and lower possible deviations from that value, a rectangular distribution might be used to represent state-of-knowledge about the quantity. If the deviations are themselves known by probability

Efficient Algorithms for T-way Test Sequence Generation

October 16, 2012
Author(s)
Linbin Yu, Yu Lei, Raghu N. Kacker, D. Richard Kuhn, James F. Lawrence
Combinatorial testing has been shown to be a very effective testing strategy. Most work on combinatorial testing focuses on t-way test data generation, where each test is an unordered set of parameter values. In this paper, we study the problem of t-way

Combinatorial Methods for Event Sequence Testing

April 21, 2012
Author(s)
D. Richard Kuhn, James M. Higdon, James F. Lawrence, Raghu N. Kacker, Yu Lei
Many software testing problems involve sequences. This paper presents an application of combinatorial methods to testing problems for which it is important to test multiple configurations, but also to test the order in which events occur. For example, the

A Survey of Binary Covering Arrays

April 7, 2011
Author(s)
James F. Lawrence, Raghu N. Kacker, Yu Lei, David R. Kuhn, Michael Forbes
Two-valued covering arrays of strength t are 0--1 matrices having the property that for each t columns and each of the possible 2t sequences of t 0's and 1's, there exists a row having that sequence in that set of t columns. Covering arrays are an

Derivation of Isosceles Trapezoidal Distribution

December 1, 2010
Author(s)
Raghu N. Kacker, James F. Lawrence
It is known that, if the mid-point of a rectangular distribution is specified, the half-width is inexactly known, and the state of knowledge about the half-width may be represented by a narrower rectangular distribution then the resulting distribution

A Combinatorial Approach to Building Navigation Graphs for Dynamic Web Applications

September 20, 2009
Author(s)
Raghu N. Kacker, David R. Kuhn, James F. Lawrence, Wenhua Wang, Yu Lei, Sreedevi Sampath
Modeling the navigation structure of a dynamic web application is a challenging task because of the presence of dynamic pages. In particular, there are two problems to be dealt with: (1) the page explosion problem, i.e., the number of dynamic pages may be

Refining the In-Parameter-Order Strategy for Constructing Covering Arrrays

September 1, 2008
Author(s)
Michael Forbes, James F. Lawrence, Yu Lei, Raghu N. Kacker, D. Richard Kuhn
Covering arrays are structures for well-representing extremely large input spaces and are used to efficiently implement blackbox testing for software and hardware. This paper proposes refinements over the In-Parameter-Order strategy (for arbitrary $t$)

IPOG/IPOG-D: Efficient Test Generation for Multi-way Combinatorial Testing

November 29, 2007
Author(s)
Yu Lei, Raghu N. Kacker, D. Richard Kuhn, Vadim Okun, James F. Lawrence
We present two strategies for multi-way testing (i.e., t-way testing with t > 2). The first strategy generalizes an existing strategy, called In-Parameter-Order, from pairwise testing to multi-way testing. This strategy requires all t-way combinations to

IPOG: A General Strategy for t-Way Software Testing

March 29, 2007
Author(s)
Yu Lei, Raghu N. Kacker, D. Richard Kuhn, Vadim Okun, James F. Lawrence
Most existing work on t-way testing has focused on 2-way (or pairwise) testing, which aims to detect faults caused by interactions between any two parameters. However, faults can also be caused by interactions involving more than two parameters. In this

Three Rings of Polyhedral Simple Functions

March 1, 2006
Author(s)
James F. Lawrence
We survey three ways to multiply elements of the additive subgroup of the group of real--valued functions on Rd which is generated by the indicator functions of polyhedra. In the resulting commutative rings, identities often correspond to useful techniques