We consider a classical k-center problem in trees. Let T be a tree of n vertices and every vertex has a nonnegative weight. The problem is to find k centers on the edges of T such that the maximum weighted distance from all vertices to their closest centers is minimized. Megiddo and Tamir (SIAM J. Comput., 1983) gave an algorithm that can solve the problem in O(n log n) time by using Cole’s par...

The robustness of agility metrics has been studied to determine the sensitivity of selected metrics to variations in initial conditions and uncertainties in physical characteristics and coefŽ cients. The selected metrics are time to roll through bank anglemetric, time-averaged integral of pitch rate metric, and power onset/loss parameter. Each metric was evaluated with initial condition errors ...

We consider the construction of adaptive controllers for minimum phase linear systems which achieve non-zero robustness margins in the sense of the (linear) L2[0,∞) gap metric. The gap perturbations may be more constrained for larger disturbances and for larger parametric uncertainty. Working within the framework of the nonlinear gap metric [3], universal adaptive controllers are first given ac...

In this paper we underline the importance of the parametric subregularity property of setvalued mappings, de…ned with respect to …xed sets. We show that this property appears naturally for some very simple mappings which play an important role in the theory of metric regularity. We prove a result concerning the preservation of metric subregularity at generalized compositions. Then we obtain, on...

In this article, we analyze the morphometry (shape and size) of hippocampus in subjects with very mild dementia of Alzheimer’s type (DAT) and nondemented controls and how the morphometry changes over a two-year period. Morphometric differences with respect to a template hippocampus were measured by the metric distance obtained from the Large Deformation Diffeomorphic Metric Mapping (LDDMM) algo...

We present the first results from SPHINX-MHD, a suite of cosmological radiation-magnetohydrodynamics simulations designed to study impact primordial magnetic fields (PMFs) on galaxy formation and evolution intergalactic medium during epoch reionization. The are among employ multi-frequency, on-the-fly radiation transfer constrained transport ideal MHD in context simultaneously model inhomogeneo...

We study the two field model for reheating based on the scalar inflaton field, φ, and its interaction with another scalar field, χ, through a Lagrangian term 1 2 gχφ,much investigated for parametric resonance or preheating. Attention is particularly on the quantum excitations of the inflaton field and the metric with a smooth transition from quantum to classical stochastic states, and with rehe...

The issues of validity and reliability are important in forensic science. Within the likelihood-ratio framework for the evaluation of forensic evidence, the log-likelihood-ratio cost (Cllr) has been applied as an appropriate metric for evaluating the accuracy of the output of a forensic-voice-comparison system, but there has been little research on developing a quantitative metric of precision....

The area under the ROC (Receiver Operating Characteristic) curve, or simply AUC, has been widely used to measure model performance for binary classification tasks. It can be estimated under parametric, semiparametric and nonparametric assumptions. The non-parametric estimate of the AUC, which is calculated from the ranks of predicted scores of instances, does not always sufficiently take advant...

We study the two field model for reheating based on the scalar inflaton field, φ, and its interaction with another scalar field, χ, through a Lagrangian term 1 2 gχφ,much investigated for parametric resonance or preheating. Attention is particularly on the quantum excitations of the inflaton field and the metric with a smooth transition from quantum to classical stochastic states, and with rehe...