In this work we present a predictive analytical model that encompasses the performance and scaling characteristics of an important ASCI application. SAGE (SAIC’s Adaptive Grid Eulerian hydrocode) is a multidimensional hydrodynamics code with adaptive mesh refinement. The model is validated against measurements on several systems including ASCI Blue Mountain, ASCI White, and a Compaq Alphaserver ES45 system showing high accuracy. It is parametric- basic machine performance numbers (latency, MFLOPS rate, bandwidth) and application characteristics (problem size, decomposition method, etc.) serve as input. The model is applied to add insight into the performance of current systems, to reveal bottlenecks, and to illustrate where tuning efforts can be effective. We also use the model to predict performance on future systems.

The vast majority of the literature dealing with quantum dynamics is concerned with linear evolution of the wave function or the density matrix. A complete dynamical description requires a full understanding of the evolution of measured quantum systems, necessary to explain actual experimental results. The dynamics of such systems is intrinsically nonlinear even at the level of distribution functions, both classically as well as quantum mechanically. Aside from being physically more complete, this treatment reveals the existence of dynamical regimes, such as chaos, that have no counterpart in the linear case. Here, we present a short introductory review of some of these aspects, with a few illustrative results and examples. Keywords: chaos, conditioned evolution, continuous measurement, density matrix, quantum backaction, quantum feedback 1.

wear in rotating machinery. Engineers at Los Alamos National Laboratory (LANL) have been actively involved in SHM research for many years. These activities have been supported by internal research funds, direct programmatic efforts, partnerships with industry, and external work for other nondefense

The paper presents some examples of the use of remote sensing products for characterization of hazardous waste sites. The sites are located at the Los Alamos National Laboratory (LANL) where materials associated with past weapons testing are buried. Problems of interest include the detection

A baseline transportation network for Los Alamos National Laboratory (LANL) was assembled to perform evacuation and other traffic simulations. This network was created from existing LANL databases and cast in the input data structure for TRANSIMS, the LANL-developed microsimulation tool

the research community for such monitoring. The basic premise of vibration-based damage detection is that the damage will significantly alter the stiffness, mass or energy dissipation properties of a system, which, in turn, will alter the measured dynamic response of that system. Staff at Los Alamos National

metrics for test-analysis correlation is also addressed. Our approach is illustrated using data from a nonlinear vibration testbed and an impact experiment both conducted at Los Alamos National Laboratory in support of the advanced strategic computing initiative and our code validation and verification

LOS ALAMOS NATIONAL LABORATORY,

Large N-body simulations on parallel supercomputers allow one to simultaneously investigate large scale structure and the formation of galactic halos with unprecedented resolution. Our study shows that the masses as well as spatial distribution of halos on scales of tens of megaparsecs in a cold dark matter (CDM) Universe with the spectrum normalized to the anisotropies detected by COBE is compatible with the observations. We also show that the average value of the relative pairwise velocity dispersion oe v --- used as a principal argument against COBE-normalized CDM models --- is significantly lower for halos than for individual particles. When the observational methods of extracting oe v are applied to the redshift catalogs obtained from the numerical experiments, estimates differ significantly between different observation-sized samples, and overlap observational estimates obtained following the same procedure. 1. INTRODUCTION Numerical studies of the cold dark matter scenario were...

Large N-body simulations on parallel supercomputers allow one to simultaneously investigate large scale structure and the formation of galactic halos with unprecedented resolution. Our study shows that the masses as well as spatial distribution of halos on scales of tens of megaparsecs in a cold dark matter (CDM) Universe with the spectrum normalized to the anisotropies detected by COBE is compatible with the observations. We also show that the average value of the relative pairwise velocity dispersion oe v --- used as a principal argument against COBE-normalized CDM models --- is significantly lower for halos than for individual particles. When the observational methods of extracting oe v are applied to the redshift catalogs obtained from the numerical experiments, estimates differ significantly between different observation-sized samples, and overlap observational estimates obtained following the same procedure. 1. INTRODUCTION Numerical studies of the cold dark matter scenario wer...