180 results on '"R W Anderson"'
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2. The Collaboration Between Art and Technology: Making Disney Animation's 'Myth: A Frozen Tale'.
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Jeff Gipson, Jose Luis Gomez Diaz, Michael R. W. Anderson, Edward Robbins 0002, Brittney Lee, and Nicholas Russell
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- 2020
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3. SNS: A Solution-Based Nonlinear Subspace Method for Time-Dependent Model Order Reduction
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R W Anderson, Youngsoo Choi, and Deshawn Coombs
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Nonlinear model order reduction ,Order reduction ,Applied Mathematics ,Numerical Analysis (math.NA) ,Reduced order ,Nonlinear dynamical systems ,Computational Mathematics ,Nonlinear system ,Hyper reduction ,Dependent model ,FOS: Mathematics ,Applied mathematics ,Mathematics - Numerical Analysis ,Subspace topology ,Mathematics - Abstract
Several reduced order models have been developed for nonlinear dynamical systems. To achieve a considerable speed-up, a hyper-reduction step is needed to reduce the computational complexity due to nonlinear terms. Many hyper-reduction techniques require the construction of nonlinear term basis, which introduces a computationally expensive offline phase. A novel way of constructing nonlinear term basis within the hyper-reduction process is introduced. In contrast to the traditional hyper-reduction techniques where the collection of nonlinear term snapshots is required, the SNS method avoids collecting the nonlinear term snapshots. Instead, it uses the solution snapshots that are used for building a solution basis, which enables avoiding an extra data compression of nonlinear term snapshots. As a result, the SNS method provides a more efficient offline strategy than the traditional model order reduction techniques, such as the DEIM, GNAT, and ST-GNAT methods. The SNS method is theoretically justified by the conforming subspace condition and the subspace inclusion relation. It is useful for model order reduction of large-scale nonlinear dynamical problems to reduce the offline cost. It is especially useful for ST-GNAT that has shown promising results, such as a good accuracy with a considerable online speed-up for hyperbolic problems in a recent paper by Choi and Carlberg in SISC 2019, because ST-GNAT involves an expensive offline cost related to collecting nonlinear term snapshots. Numerical results support that the accuracy of the solution from the SNS method is comparable to the traditional methods and a considerable speed-up (i.e., a factor of two to a hundred) is achieved in the offline phase., 26 pages, 16 figures
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- 2020
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4. MFEM
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Will Pazner, Jakub Cerveny, M L Stowell, Tzanio V. Kolev, Stefano Zampini, R W Anderson, Johann Dahm, Jean-Sylvain Camier, Aaron Fisher, Veselin Dobrev, Ido Akkerman, David Medina, Andrew T. Barker, Jamie A. Bramwell, Yohann Dudouit, Julian Andrej, and Vladimir Tomov
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FOS: Computer and information sciences ,Finite element methods ,Discretization ,010103 numerical & computational mathematics ,01 natural sciences ,Computational science ,Software portability ,High-order methods ,FOS: Mathematics ,Polygon mesh ,Mathematics - Numerical Analysis ,0101 mathematics ,High-performance computing ,Mathematics ,Open-source scientific software ,business.industry ,Usability ,Numerical Analysis (math.NA) ,Modular design ,Supercomputer ,Finite element method ,010101 applied mathematics ,Computational Mathematics ,Computational Theory and Mathematics ,Matrix-free algorithms ,Modeling and Simulation ,Scalability ,Computer Science - Mathematical Software ,business ,Numerical PDEs ,Mathematical Software (cs.MS) - Abstract
MFEM is an open-source, lightweight, flexible and scalable C++ library for modular finite element methods that features arbitrary high-order finite element meshes and spaces, support for a wide variety of discretization approaches and emphasis on usability, portability, and high-performance computing efficiency. MFEM's goal is to provide application scientists with access to cutting-edge algorithms for high-order finite element meshing, discretizations and linear solvers, while enabling researchers to quickly and easily develop and test new algorithms in very general, fully unstructured, high-order, parallel and GPU-accelerated settings. In this paper we describe the underlying algorithms and finite element abstractions provided by MFEM, discuss the software implementation, and illustrate various applications of the library., Comment: 36 pages, 21 figures
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- 2021
5. The Multiphysics on Advanced Platforms Project
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L. Busby, B. Olson, R.B. Pember, R W Anderson, Kenneth Weiss, Veselin Dobrev, Thomas Stitt, N. S. Elliott, M. Osawe, A. Skinner, J. Ciurej, Richard D. Hornung, D. Stevens, R. Rieben, Vladimir Tomov, A. Black, B. Blakeley, L. R. Taylor, Cyrus Harrison, Daniel A. White, W. Liu, Jean-Sylvain Camier, W. Nissen, Arturo Vargas, J. Grondalski, Matthew Legendre, Andrew W. Cook, Olga Pearce, Ryan Bleile, Tz. V. Kolev, and G. Papadimitriou
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Computer science ,Multiphysics ,Systems engineering - Published
- 2020
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6. High-Order Multi-Material ALE Hydrodynamics
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R W Anderson, Vladimir Tomov, R. Rieben, Tzanio V. Kolev, and Veselin Dobrev
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Curvilinear coordinates ,State variable ,Applied Mathematics ,Relaxation (iterative method) ,010103 numerical & computational mathematics ,Interval (mathematics) ,01 natural sciences ,Finite element method ,010101 applied mathematics ,Computational Mathematics ,Elliptic curve ,Discontinuous Galerkin method ,Applied mathematics ,Polygon mesh ,0101 mathematics ,Mathematics - Abstract
We present a new approach for multi-material arbitrary Lagrangian--Eulerian (ALE) hydrodynamics simulations based on high-order finite elements posed on high-order curvilinear meshes. The method builds on and extends our previous work in the Lagrangian [V. A. Dobrev, T. V. Kolev, and R. N. Rieben, SIAM J. Sci. Comput., 34 (2012), pp. B606--B641] and remap [R. W. Anderson et al., Internat. J. Numer. Methods Fluids, 77 (2015), pp. 249--273] phases of ALE, and depends critically on a functional perspective that enables subzonal physics and material modeling [V. A. Dobrev et al., Internat. J. Numer. Methods Fluids, 82 (2016), pp. 689--706]. Curvilinear mesh relaxation is based on node movement, which is determined through the solution of an elliptic equation. The remap phase is posed in terms of advecting state variables between two meshes over a fictitious time interval. The resulting advection equation is solved by a discontinuous Galerkin (DG) formulation, combined with a customized Flux Corrected Transpor...
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- 2018
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7. High-order local maximum principle preserving (MPP) discontinuous Galerkin finite element method for the transport equation
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Veselin Dobrev, R W Anderson, R. Rieben, Vladimir Tomov, Dmitri Kuzmin, M. Quezada de Luna, and Tz. V. Kolev
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Numerical Analysis ,Physics and Astronomy (miscellaneous) ,Discretization ,Applied Mathematics ,Mathematical analysis ,Basis function ,010103 numerical & computational mathematics ,Mixed finite element method ,Space (mathematics) ,01 natural sciences ,Finite element method ,Computer Science Applications ,010101 applied mathematics ,Computational Mathematics ,Maximum principle ,Discontinuous Galerkin method ,Modeling and Simulation ,0101 mathematics ,Mathematics ,Extended finite element method - Abstract
In this work we present a FCT- like Maximum-Principle Preserving (MPP) method to solve the transport equation. We use high-order polynomial spaces; in particular, we consider up to 5th order spaces in two and three dimensions and 23rd order spaces in one dimension. The method combines the concepts of positive basis functions for discontinuous Galerkin finite element spatial discretization, locally defined solution bounds, element-based flux correction, and non-linear local mass redistribution. We consider a simple 1D problem with non-smooth initial data to explain and understand the behavior of different parts of the method. Convergence tests in space indicate that high-order accuracy is achieved. Numerical results from several benchmarks in two and three dimensions are also reported.
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- 2017
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8. Advances in patch-based adaptive mesh refinement scalability
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R W Anderson and Brian T. N. Gunney
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010308 nuclear & particles physics ,Computer Networks and Communications ,Computer science ,Adaptive mesh refinement ,Parallel computing ,01 natural sciences ,010305 fluids & plasmas ,Theoretical Computer Science ,Set (abstract data type) ,Artificial Intelligence ,Hardware and Architecture ,0103 physical sciences ,Scalability ,Key (cryptography) ,Polygon mesh ,Cluster analysis ,Software - Abstract
Patch-based structured adaptive mesh refinement (SAMR) is widely used for high-resolution simulations. Combined with modern supercomputers, it could provide simulations of unprecedented size and resolution. A persistent challenge for this combination has been managing dynamically adaptive meshes on more and more MPI tasks. The distributed mesh management scheme in SAMRAI has made some progress SAMR scalability, but early algorithms still had trouble scaling past the regime of 10 5 MPI tasks. This work provides two critical SAMR regridding algorithms, which are integrated into that scheme to ensure efficiency of the whole. The clustering algorithm is an extension of the tile-clustering approach, making it more flexible and efficient in both clustering and parallelism. The partitioner is a new algorithm designed to prevent the network congestion experienced by its predecessor. We evaluated performance using weak- and strong-scaling benchmarks designed to be difficult for dynamic adaptivity. Results show good scaling on up to 1.5M cores and 2M MPI tasks. Detailed timing diagnostics suggest scaling would continue well past that. We developed two key SAMR regridding components that scaled individually and integrated scalably.The cascade partitioner took 10% of the regrid time and yielded loads within 10% of ideal.The tile clustering step took about 2% of regrid time and reduced cluster counts by a factor of 38.Our benchmarks, set up to be challenging for dynamic adaptivity, scaled to 2M MPI tasks.Smooth, well-behaved timer trends indicate higher scaling is possible.
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- 2016
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9. Space–time reduced order model for large-scale linear dynamical systems with application to Boltzmann transport problems
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Peter Brown, William J. Arrighi, Kevin Huynh, Youngsoo Choi, and R W Anderson
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Numerical Analysis ,Physics and Astronomy (miscellaneous) ,Basis (linear algebra) ,Scale (ratio) ,Computer science ,Applied Mathematics ,Space time ,Degrees of freedom (statistics) ,Computer Science Applications ,Linear dynamical system ,Reduction (complexity) ,Computational Mathematics ,Approximation error ,Modeling and Simulation ,Scalability ,Applied mathematics - Abstract
A classical reduced order model for dynamical problems involves spatial reduction of the problem size. However, temporal reduction accompanied by the spatial reduction can further reduce the problem size without losing much accuracy, which results in a considerably more speed-up than the spatial reduction only. Recently, a novel space–time reduced order model for dynamical problems has been developed [17] , where the space–time reduced order model shows an order of a hundred speed-up with a relative error of 10 − 4 for small academic problems. However, in order for the method to be applicable to a large-scale problem, an efficient space–time reduced basis construction algorithm needs to be developed. We present the incremental space–time reduced basis construction algorithm. The incremental algorithm is fully parallel and scalable. Additionally, the block structure in the space–time reduced basis is exploited, which enables the avoidance of constructing the reduced space–time basis. These novel techniques are applied to a large-scale particle transport simulation with million and billion degrees of freedom. The numerical example shows that the algorithm is scalable and practical. Also, it achieves a tremendous speed-up, maintaining a good accuracy. Finally, error bounds for space-only and space–time reduced order models are derived.
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- 2021
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10. An AMR Capable Finite Element Diffusion Solver for ALE Hydrocodes
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Alice Koniges, Nathan Masters, R W Anderson, Brian T. N. Gunney, T B Kaiser, D S Bailey, D. C. Eder, and Aaron Fisher
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Diffusion equation ,Adaptive mesh refinement ,Thermal radiation ,Computer science ,Convergence (routing) ,Computer Science::Mathematical Software ,Statistical physics ,Diffusion (business) ,Solver ,Condensed Matter Physics ,Thermal conduction ,Finite element method ,Computational science - Abstract
We present a novel method for the solution of the diffusion equation on a composite AMR mesh. This approach is suitable for including diffusion based physics modules to hydrocodes that support ALE and AMR capabilities. To illustrate, we proffer our implementations of diffusion based radiation transport and heat conduction in a hydrocode called ALE-AMR. Numerical experiments conducted with the diffusion solver and associated physics packages yield 2nd order convergence in the L2 norm.
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- 2015
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11. Monotonicity in high‐order curvilinear finite element arbitrary Lagrangian–Eulerian remap
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R W Anderson, R. Rieben, Tz. V. Kolev, and Veselin Dobrev
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Mathematical optimization ,Curvilinear coordinates ,State variable ,Applied Mathematics ,Mechanical Engineering ,Computational Mechanics ,Context (language use) ,Monotonic function ,Interval (mathematics) ,Finite element method ,Mathematics::Numerical Analysis ,Computer Science Applications ,Maxima and minima ,Mechanics of Materials ,Discontinuous Galerkin method ,Applied mathematics ,ComputingMethodologies_COMPUTERGRAPHICS ,Mathematics - Abstract
Summary The remap phase in arbitrary Lagrangian–Eulerian (ALE) hydrodynamics involves the transfer of field quantities defined on a post-Lagrangian mesh to some new mesh, usually generated by a mesh optimization algorithm. This problem is often posed in terms of transporting (or advecting) some state variable from the old mesh to the new mesh over a fictitious time interval. It is imperative that this remap process be monotonic, that is, not generate any new extrema in the field variables. It is well known that the only linear methods that are guaranteed to be monotonic for such problems are first-order accurate; however, much work has been performed in developing non-linear methods, which blend both high and low (first) order solutions to achieve monotonicity and preserve high-order accuracy when the field is sufficiently smooth. In this paper, we present a set of methods for enforcing monotonicity targeting high-order discontinuous Galerkin methods for advection equations in the context of high-order curvilinear ALE hydrodynamics. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
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- 2014
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12. Modeling NIF experimental designs with adaptive mesh refinement and Lagrangian hydrodynamics
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Marilyn Schneider, Brian T. N. Gunney, R W Anderson, B. J. MacGowan, P Wang, R Becker, David C. Eder, and Alice Koniges
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Radiation transport ,Computer simulation ,Adaptive mesh refinement ,Computer science ,Computation ,Design of experiments ,General Physics and Astronomy ,Statistical physics ,Fusion power ,National Ignition Facility ,Lagrangian hydrodynamics ,Computational science - Abstract
Incorporation of adaptive mesh refinement (AMR) into Lagrangian hydrodynamics algorithms allows for the creation of a highly powerful simulation tool effective for complex target designs with three-dimensional structure. We are developing an advanced modeling tool that includes AMR and traditional arbitrary Lagrangian-Eulerian (ALE) techniques. Our goal is the accurate prediction of vaporization, disintegration and fragmentation in National Ignition Facility (NIF) experimental target elements. Although our focus is on minimizing the generation of shrapnel in target designs and protecting the optics, the general techniques are applicable to modern advanced targets that include three-dimensional effects such as those associated with capsule fill tubes. Several essential computations in ordinary radiation hydrodynamics need to be redesigned in order to allow for AMR to work well with ALE, including algorithms associated with radiation transport. Additionally, for our goal of predicting fragmentation, we include elastic/plastic flow into our computations. We discuss the integration of these effects into a new ALE-AMR simulation code. Applications of this newly developed modeling tool as well as traditional ALE simulations in two and three dimensions are applied to NIF early-light target designs.
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- 2006
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13. Optimization of experimental designs by incorporating NIF facility impacts
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Brian T. N. Gunney, R W Anderson, Pamela K. Whitman, J. G. Koerner, B. J. MacGowan, Harry Robey, Mary L. Spaeth, Tayyab I. Suratwala, M. T. Tobin, S. N. Dixit, Thomas Gene Parham, Alice Koniges, B. E. Blue, J. F. Hansen, P Wang, and David C. Eder
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Design of experiments ,Source orientation ,Nuclear engineering ,Electromagnetic shielding ,General Physics and Astronomy ,Environmental science ,Shields ,Pinhole ,Fusion power ,National Ignition Facility ,Debris - Abstract
For experimental campaigns on the National Ignition Facility (NIF) to be successful, they must obtain useful data without causing unacceptable impact on the facility. Of particular concern is excessive damage to optics and diagnostic components. There are 192 fused silica main debris shields (MDS) exposed to the potentially hostile target chamber environment on each shot. Damage in these optics results either from the interaction of laser light with contamination and pre-existing imperfections on the optic surface or from the impact of shrapnel fragments. Mitigation of this second damage source is possible by identifying shrapnel sources and shielding optics from them. It was recently demonstrated that the addition of 1.1-mm thick borosilicate disposable debris shields (DDS) blocks the majority of debris and shrapnel fragments from reaching the relatively expensive MDS's. However, DDS's cannot stop large, fast moving fragments. We have experimentally demonstrated one shrapnel mitigation technique showing that it is possible to direct fast moving fragments by changing the source orientation, in this case a Ta pinhole array. Another mitigation method is to change the source material to one that produces smaller fragments. Simulations and validating experiments are necessary to determine which fragments can penetrate or break 1-3 mm thick DDS's. Three-dimensional modeling of complex target-diagnostic configurations is necessary to predict the size, velocity, and spatial distribution of shrapnel fragments. The tools we are developing will be used to assure that all NIF experimental campaigns meet the requirements on allowed level of debris and shrapnel generation.
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- 2006
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14. Classification of events with an off-site radiological impact at the Sellafield site between 1950 and 2000, using the International Nuclear Event Scale
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R W Anderson, G A M Webb, and M J S Gaffney
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History ,Operations research ,Event (computing) ,Public Health, Environmental and Occupational Health ,International Nuclear Event Scale ,Environmental Exposure ,General Medicine ,Environmental exposure ,Radiation Dosage ,Risk Assessment ,United Kingdom ,Unified system ,Nuclear Reactors ,Radiological weapon ,Humans ,Operations management ,Radioactive Hazard Release ,Waste Management and Disposal ,Power Plants ,Radioactive Pollutants ,Retrospective Studies ,Rating scheme - Abstract
The paper assesses unplanned operational events at the Sellafield nuclear installation, formerly Windscale and Calder Works, in Cumbria, England, over the period 1950-2000 that had, or could have had, radiological implications for members of the general public. A unified system of off-site impact rating has been developed using a site-specific application of the International Nuclear Event Scale (INES) that is applied retrospectively to events since the start of operations at the site in 1950. Published and unpublished sources of information have been used to assemble what the authors believe to be a complete list of events over the period that would now be assessed as INES level 3 or above on the basis of off-site impact. The last such event occurred in 1984. The exercise also demonstrates that it is possible to apply the current INES rating scheme to a wide variety of radiological events.
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- 2006
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15. An arbitrary Lagrangian–Eulerian method with adaptive mesh refinement for the solution of the Euler equations
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R W Anderson, R.B. Pember, and N. S. Elliott
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Numerical Analysis ,Mathematical optimization ,Physics and Astronomy (miscellaneous) ,Adaptive mesh refinement ,Applied Mathematics ,MathematicsofComputing_NUMERICALANALYSIS ,Relaxation (iterative method) ,Context (language use) ,Grid ,Computer Science Applications ,Euler equations ,Computational Mathematics ,symbols.namesake ,Operator (computer programming) ,Modeling and Simulation ,symbols ,Applied mathematics ,Polygon mesh ,Boundary value problem ,ComputingMethodologies_COMPUTERGRAPHICS ,Mathematics - Abstract
A new algorithm that combines staggered grid arbitrary Lagrangian-Eulerian (ALE) techniques with structured local adaptive mesh refinement (AMR) has been developed for the solution of the Euler equations. The novel components of the method are driven by the need to reconcile traditional AMR techniques with the staggered variables and moving, deforming meshes associated with Lagrange based ALE schemes. Interlevel coupling is achieved with refinement and coarsening operators, as well as mesh motion boundary conditions. Elliptic mesh relaxation schemes are extended for use within the context of an adaptive mesh hierarchy. Numerical examples are used to highlight the utility of the method over single level ALE solution methods, facilitating substantial efficiency improvements and enabling the efficient solution of a highly resolved three-dimensional Richtmyer-Meshkov instability problem.
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- 2004
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16. Multi-material ALE with AMR for modeling hot plasmas and cold fragmenting materials
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David J. Benson, Wangyi Liu, Andrea L. Bertozzi, Nathan Masters, R W Anderson, Alice Koniges, Aaron Fisher, and David C. Eder
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Coalescence (physics) ,Physics ,multi-physics simulations ,Adaptive mesh refinement ,business.industry ,Extreme ultraviolet lithography ,arbitrary lagrangian eulerian hydrodynamics ,Fluids & Plasmas ,NIF ,Molecular ,laser ray tracing ,Plasma ,Plasticity ,Solver ,Warm dense matter ,Condensed Matter Physics ,Thermal conduction ,Atomic ,Particle and Plasma Physics ,fragmentation ,adaptive mesh refinement ,Nuclear ,Statistical physics ,Aerospace engineering ,business - Abstract
We have developed a new 3D multi-physics multi-material code, ALE-AMR, which combines Arbitrary Lagrangian Eulerian (ALE) hydrodynamics with Adaptive Mesh Refinement (AMR) to connect the continuum to the microstructural regimes. The code is unique in its ability to model hot radiating plasmas and cold fragmenting solids. New numerical techniques were developed for many of the physics packages to work efficiently on a dynamically moving and adapting mesh. We use interface reconstruction based on volume fractions of the material components within mixed zones and reconstruct interfaces as needed. This interface reconstruction model is also used for void coalescence and fragmentation. A flexible strength/failure framework allows for pluggable material models, which may require material history arrays to determine the level of accumulated damage or the evolving yield stress in J2 plasticity models. For some applications laser rays are propagating through a virtual composite mesh consisting of the finest resolution representation of the modeled space. A new 2nd order accurate diffusion solver has been implemented for the thermal conduction and radiation transport packages. One application area is the modeling of laser/target effects including debris/shrapnel generation. Other application areas include warm dense matter, EUV lithography, and material wall interactions for fusion devices.
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- 2015
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17. Reliability and durability from large heat recovery steam generators
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M Pearson and R. W. Anderson
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Thermal fatigue ,Engineering ,business.industry ,Heat recovery steam generator ,Mechanical Engineering ,Heat recovery ventilation ,Electrical engineering ,Boiler (power generation) ,Energy Engineering and Power Technology ,business ,Process engineering ,Durability - Abstract
Experience with heat recovery steam generators (HRSGs) designed for larger-heat-input and higher-steam conditions highlights limitations in some features of traditional designs extrapolated from smaller HRSGs that operated predominantly continuously. Many combined-cycle units may be subjected to periods of regular overnight shut-down much earlier than expected and, unless anticipated during the initial design, there will be significant adverse impact on reliability and durability. Very premature problems already experienced on large HRSG designs in combined-cycle and cogeneration applications give an early warning that more widespread problems will arise as HRSGs are subjected to more thermal cycling. Problems that arise when inadequate attention is given to transient conditions over the full range of operation of the combined-cycle gas turbine unit, including at part loads, during shut-downs and restarts from diverse pre-start conditions, are highlighted. The paper gives examples of how the damage to HRSGs during shut-down and starts can be mitigated by minor modifications and sympathetic operating procedures and suggests how prudent purchasers can enhance reliability and lower lifetime costs at a small premium in installed cost by specification of appropriate design features. Other weaknesses which cause problems for operation and maintenance are discussed.
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- 1999
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18. EXPERIENCES IN PREPARING A CNMP EMERGENCY RESPONSE PLAN FOR A TENNESSEE DAIRY FARM
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R. W. Anderson, G. F. Grandle, Robert T. Burns, and Lara B. Moody
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Engineering ,Emergency response ,business.industry ,Plan (drawing) ,business ,Water resource management ,Environmental planning - Published
- 2013
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19. Three-dimensional wake formations behind a family of regular polygonal plates
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R. W. Anderson, Hiroshi Higuchi, and Jie Zhang
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Physics ,Flow visualization ,Aerospace Engineering ,Reynolds number ,Geometry ,Tourbillon ,Wake ,Vortex ,Physics::Fluid Dynamics ,symbols.namesake ,Acceleration ,symbols ,Navier–Stokes equations ,Freestream - Abstract
The experiments were conducted in water to study the initial wake formations behind various polygonal plates placed normal to the starting flow. The models included triangular, square, hexagonal, and octagonal plates. Because of nonuniform self-induced velocity, the initial vortex structure behind each polygonal plate was arched in the axial direction, and pairs of counter-rotating longitudinal vortices induced inward motion of the vortex structure at each corner. The evolution of free polygonal vortex loops was numerically simulated using a simplified three-dimensional vortex segment method to demonstrate the mechanism for the observed vortex deformation. Nomenclature Ap . = acceleration parameter, Deqa/ UQ a = acceleration, dU/dt D = side length of square plate Z)eq = equivalent disk diameter Re = steady-state Reynolds number, Rec = acceleration Reynolds number, T = nondimensional time, U0t/Deq t = time tc = time scale, J(Deq/d) U = freestream velocity UQ = steady freestream velocity X = axial distance v = kinematic viscosity
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- 1996
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20. Airborne Hyperspectral Imaging of Laurentian Great Lakes: Operational Challenges
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John Lekki, Joseph M. Flatico, R W Anderson, Quang-Viet Nguyen, Jun Kojima, James Demers, George Leshkevich, and Roger Tokars
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Environmental science ,Hyperspectral imaging ,Remote sensing - Published
- 2010
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21. A Predictive Model of Fragmentation using Adaptive Mesh Refinement and a Hierarchical Material Model
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D C Eder, P Wang, T B Kaiser, Brian T. N. Gunney, M A Meyers, D H Kalantar, N. Masters, A C Fisher, A. Koniges, R W Anderson, J. F. Hansen, D Benson, H Jarmakani, P Dixit, and Brian Maddox
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Materials science ,Adaptive mesh refinement ,Mechanical engineering ,Reconstruction algorithm ,Material failure theory ,National Ignition Facility ,3d simulation ,Hidden Markov model ,Computational science - Abstract
Fragmentation is a fundamental material process that naturally spans spatial scales from microscopic to macroscopic. We developed a mathematical framework using an innovative combination of hierarchical material modeling (HMM) and adaptive mesh refinement (AMR) to connect the continuum to microstructural regimes. This framework has been implemented in a new multi-physics, multi-scale, 3D simulation code, NIF ALE-AMR. New multi-material volume fraction and interface reconstruction algorithms were developed for this new code, which is leading the world effort in hydrodynamic simulations that combine AMR with ALE (Arbitrary Lagrangian-Eulerian) techniques. The interface reconstruction algorithm is also used to produce fragments following material failure. In general, the material strength and failure models have history vector components that must be advected along with other properties of the mesh during remap stage of the ALE hydrodynamics. The fragmentation models are validated against an electromagnetically driven expanding ring experiment and dedicated laser-based fragmentation experiments conducted at the Jupiter Laser Facility. As part of the exit plan, the NIF ALE-AMR code was applied to a number of fragmentation problems of interest to the National Ignition Facility (NIF). One example shows the added benefit of multi-material ALE-AMR that relaxes the requirement that material boundaries must be along mesh boundaries.
- Published
- 2009
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22. Shear Wall Resistance of Lightgage Steel Stud Wall Systems
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J. Gregory, J. Elmlinger, V. Avanessian, S. A. Adham, R. W. Anderson, and Gary C. Hart
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Geophysics ,Materials science ,Viscous damping ,business.industry ,Shear wall ,Lateral stiffness ,Structural engineering ,Dissipation ,Geotechnical Engineering and Engineering Geology ,business - Abstract
Experimental investigations were conducted to evaluate the lateral load-deflection characteristics of lightgage steel stud/gypsum wallboard panel combinations subjected to lateral cyclic loads. In all, six 8′ × 8′ specimens were tested. A reasonable one-to-one correspondence between the strap area increase and the increase in the contribution from the strap to the overall loadcarrying capacity of the panel at intermediate and high drift ratios was observed. The panel lateral stiffness for a given stabilized cycle degraded by about 7% to 15% as compared with the lateral stiffness of the corresponding virgin cycle. Lateral stiffness degradation increased as the drift ratios became larger. The energy dissipation ability of the panels in the stabilized cycle was about 60% of the virgin cycle. An average value of equivalent viscous damping for all the cycles based on panel hysteretic behavior was about 12%.
- Published
- 1990
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23. Research & Tool Development in Support of High Speed Sealift Concepts
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R W Anderson, C A Dicks, G R Lamb, and J D Offutt
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Engineering ,Development (topology) ,business.industry ,Systems engineering ,business - Published
- 2007
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24. A dynamically adaptive arbitrary Lagrangian-Eulerian method for hydrodynamics
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R W Anderson, R.B. Pember, and N. S. Elliott
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symbols.namesake ,Mathematical optimization ,Adaptive mesh refinement ,symbols ,Hinge ,Relaxation (iterative method) ,Applied mathematics ,Arbitrary lagrangian eulerian ,Grid ,Instability ,Lagrangian ,Mathematics ,Euler equations - Abstract
A new method that combines staggered grid Arbitrary Lagrangian-Eulerian (ALE) techniques with structured local adaptive mesh refinement (AMR) has been developed for solution of the Euler equations. The novel components of the combined ALE-AMR method hinge upon the integration of traditional AMR techniques with both staggered grid Lagrangian operators as well as elliptic relaxation operators on moving, deforming mesh hierarchies. Numerical examples demonstrate the utility of the method in performing detailed three-dimensional shock-driven instability calculations.
- Published
- 2003
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25. An Arbitrary Lagrangian-Eulerian method with local structured adaptive mesh refinement for modeling shock hydrodynamics
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R.B. Pember, R W Anderson, and N. S. Elliott
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Mathematical optimization ,Adaptive mesh refinement ,MathematicsofComputing_NUMERICALANALYSIS ,Hinge ,Boundary (topology) ,Grid ,Euler equations ,Shock (mechanics) ,Computational science ,symbols.namesake ,Development (topology) ,symbols ,Polygon mesh ,Mathematics - Abstract
A new method that combines staggered grid Arbitrary Lagrangian-Eulerian (ALE) techniques with structured local adaptive mesh refinement (AMR) has been developed for solution of the Euler equations. This method facilitates the solution of problems currently at and beyond the boundary of soluble problems by traditional ALE methods by focusing computational resources where they are required through dynamic adaption. Many of the core issues involved in the development of the combined ALEAMR method hinge upon the integration of AMR with a staggered grid Lagrangian integration method. The novel components of the method are mainly driven by the need to reconcile traditional AMR techniques, which are typically employed on stationary meshes with cell-centered quantities, with the staggered grids and grid motion employed by Lagrangian methods. Numerical examples are presented which demonstrate the accuracy and efficiency of the method.
- Published
- 2002
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26. Comparison of direct Eulerian Godunov and Lagrange plus remap artificial viscosity schemes
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R W Anderson and R.B. Pember
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Godunov's scheme ,Eulerian path ,Upwind scheme ,Monotonic function ,Grid ,Compressible flow ,Physics::Fluid Dynamics ,symbols.namesake ,Classical mechanics ,Inviscid flow ,Viscosity (programming) ,symbols ,Applied mathematics ,Mathematics - Abstract
The authors compare two algorithms for solving the equations of unsteady inviscid compressible flow in an Eulerian frame: a staggered grid, Lagrange plus remap artificial viscosity scheme and a cell-centered, direct Eulerian higher-order Godunov scheme. They use the two methods to compute solutions to a number of one- and two-dimensional problems. The results show the accuracy of the two schemes to be generally equivalent. In a 1984 survey paper by Woodward and Colella, the Lagrange plus remap approach did not compare favorably with the higher-order Godunov methodology. They examine, therefore, how certain features of the staggered grid scheme considered here contribute to its improved accuracy. The critical features are shown to be the use of a monotonic artificial viscosity in the Lagrange step and, in the remap step, the use of a corner transport upwind scheme with van Leer limiters in conjunction with separate advection of internal and kinetic energies.
- Published
- 2001
- Full Text
- View/download PDF
27. Talk the game, then play the game
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R W, Anderson
- Subjects
Academic Medical Centers ,Economic Competition ,General Surgery ,Surgery Department, Hospital - Published
- 1999
28. Estimation of spatiotemporal neural activity using radial basis function networks
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R W, Anderson, S, Das, and E L, Keller
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Electrophysiology ,Superior Colliculi ,Space Perception ,Time Perception ,Motion Perception ,Saccades ,Animals ,Haplorhini ,Neural Networks, Computer ,Visual Fields ,Algorithms - Abstract
We report a method using radial basis function (RBF) networks to estimate the time evolution of population activity in topologically organized neural structures from single-neuron recordings. This is an important problem in neuroscience research, as such estimates may provide insights into systems-level function of these structures. Since single-unit neural data tends to be unevenly sampled and highly variable under similar behavioral conditions, obtaining such estimates is a difficult task. In particular, a class of cells in the superior colliculus called buildup neurons can have very narrow regions of saccade vectors for which they discharge at high rates but very large surround regions over which they discharge at low, but not zero, levels. Estimating the dynamic movement fields for these cells for two spatial dimensions at closely spaced timed intervals is a difficult problem, and no general method has been described that can be applied to all buildup cells. Estimation of individual collicular cells' spatiotemporal movement fields is a prerequisite for obtaining reliable two-dimensional estimates of the population activity on the collicular motor map during saccades. Therefore, we have developed several computational-geometry-based algorithms that regularize the data before computing a surface estimation using RBF networks. The method is then expanded to the problem of estimating simultaneous spatiotemporal activity occurring across the superior colliculus during a single movement (the inverse problem). In principle, this methodology could be applied to any neural structure with a regular, two-dimensional organization, provided a sufficient spatial distribution of sampled neurons is available.
- Published
- 1999
29. Vehicle travel speeds and the incidence of fatal pedestrian crashes
- Author
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R W, Anderson, A J, McLean, M J, Farmer, B H, Lee, and C G, Brooks
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Models, Statistical ,Ethanol ,Urban Population ,Risk Factors ,Acceleration ,Accidents, Traffic ,Australia ,Humans ,Wounds and Injuries ,Alcoholic Intoxication ,Probability - Abstract
The aim of this study was to estimate the likely effect of reduced travel speeds on the incidence of pedestrian fatalities in Adelaide, Australia. The study was based on the results of detailed investigations of 176 fatal pedestrian crashes in the Adelaide area between 1983 and 1991. The method developed to estimate the effect of reduced travelling speed is described and supported by references to the published literature. A reduction in the speed limit from 60 to 50 km/h was one of four speed reduction scenarios considered. The smallest estimated reduction in fatal pedestrian collisions in the selection presented was 13%, for a scenario in which all drivers obeyed the existing speed limit. The largest estimated reduction was 48% for a scenario in which all drivers were travelling 10 km/h slower. The estimated reductions in fatalities obtained in this study are compared with those observed in places where the urban area speed limit has been lowered.
- Published
- 1997
30. Free beta hCG screening of hydropic and non-hydropic Turner syndrome pregnancies
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C H, Laundon, K, Spencer, J N, Macri, R W, Anderson, and P D, Buchanan
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Adult ,Pregnancy Complications ,Adolescent ,Pregnancy ,Hydrops Fetalis ,Pregnancy Trimester, Second ,Humans ,Turner Syndrome ,Chorionic Gonadotropin, beta Subunit, Human ,Female ,alpha-Fetoproteins ,Down Syndrome ,Ultrasonography, Prenatal - Abstract
Fourteen cases of Turner syndrome (45,X), two cases of mosaic Turner syndrome (45,X/47,XXX and 45,X/ 46,XX), and one case of Turner syndrome involving an isochromosome X [46,X,i(X)(q10)] were ascertained by prenatal maternal serum alpha-fetoprotein (MSAFP) and free beta human chorionic gonadotropin (hCG) screening or by ultrasound. Patient-specific risks for Down syndrome were calculated and used as the criteria to determine offering further testing. Eleven of the 17 cases had hydrops and presented with an increased Down syndrome risk based on MSAFP and free beta hCG screening. The median MOM level was 0.98 and 4.04 for MSAFP and free beta hCG, respectively. Three cases had hydrops but screened negative. The two cases of mosaic Turner syndrome were non-hydropic and screened positive. The 46,X,i(X)(q10) case was non-hydropic but had elevated MSAFP and free beta hCG levels. These data suggest that Turner syndrome pregnancies do not appear to screen positive due to hydrops alone, but screening may also be influenced by the inherent genetic imbalance in the fetus and placenta. Because the MSAFP levels in our series were within the normative range in all except one case with an elevated MSAFP, free beta hCG alone was the most effective screening marker for Turner syndrome pregnancies.
- Published
- 1996
31. Fluid mechanics in a radiatively driven hypersonic wind tunnel - Prediction and preliminary experiment
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Richard B. Miles, Walter R. Lempert, Garry L. Brown, R. W. Anderson, Luigi Martinelli, and A. P. Ratta
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Physics ,business.industry ,Fluid mechanics ,Hypersonic wind tunnel ,Aerospace engineering ,business - Published
- 1996
- Full Text
- View/download PDF
32. Antigen processing in vivo and the elicitation of primary CTL responses
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N P, Restifo, I, Bacík, K R, Irvine, J W, Yewdell, B J, McCabe, R W, Anderson, L C, Eisenlohr, S A, Rosenberg, and J R, Bennink
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Antigen Presentation ,Mice, Inbred BALB C ,Vaccines, Synthetic ,Molecular Sequence Data ,Vaccinia virus ,Protein Sorting Signals ,Cytotoxicity Tests, Immunologic ,Orthomyxoviridae ,Article ,Mice ,Animals ,Female ,Amino Acid Sequence ,T-Lymphocytes, Cytotoxic - Abstract
CD8+ T lymphocytes (TCD8+) play an important role in cellular immune responses. TCD8+ recognize MHC class I molecules complexed to peptides of 8 to 10 residues derived largely from cytosolic proteins. Proteins are generally thought to be fragmented in the cytoplasm and delivered to nascent class I molecules in the endoplasmic reticulum (ER) by a peptide transporter encoded by the MHC. To explore the extent to which TCD8+ induction in vivo is limited by proteolysis or peptide transport into the ER, mice were immunized with recombinant vaccinia viruses containing mini-genes encoding antigenic peptides (bypassing the need for proteolysis), or these peptides with a NH2-terminal ER insertion sequence (bypassing the requirements for both proteolysis and transport). Additionally, mice were immunized with recombinant vaccinia viruses encoding rapidly degraded fragments of proteins. We report that limitations in induction of TCD8+ responses vary among Ags: for some, full length proteins are as immunogenic as other forms tested; for others, maximal responses are induced by peptides or by peptides targeted to the ER. Most importantly, in every circumstance examined, targeting peptides to the ER never diminished, and in some cases greatly enhanced, the TCD8+ immune response and provide an important alternative strategy in the design of live viral or naked DNA vaccines for the treatment of cancer and infectious diseases.
- Published
- 1995
33. The relationship between hospital charges and a modified Parsonnet risk score
- Author
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J C, Alexander, R J, Gottner, C E, Arentzen, and R W, Anderson
- Subjects
Health Services Needs and Demand ,Models, Economic ,Cost Control ,Data Collection ,Age Factors ,Humans ,Regression Analysis ,Cardiology Service, Hospital ,Illinois ,Coronary Artery Bypass ,Hospital Charges ,Diagnosis-Related Groups ,Forecasting - Abstract
Health care now consumes approximately 14 percent of the U.S. Gross National Product (GNP). The amount of money spent on health care in America per capita and as a percentage of GNP far exceeds that of any other industrialized country. Currently, the financial burden of health care is being shouldered by government and business. The expenditure of billions of dollars of corporate profits on health care progressively undermines the global competitiveness of American business. These economic realities have emerged as the dominant driving force in health care reform. Cost control efforts to date have focused on strategies to limit inpatient hospital expenditures. The DRG prospective payment system is designed to reimburse a fixed sum based on the diagnostic category of the patient. The DRG payment is essentially independent of underlying patient characteristics that can potentially drive up expenditures. The work reported in this article was done to develop a descriptive formula that could be used to predict resource consumption in the care of patients. The financial viability of a hospital depends on its ability to predict expenditures, allocate resources, and choose its service areas correctly. Errors in financial forecasting in the era of prospective payment will result in financial failures of entire institutions.
- Published
- 1995
34. Use of a mathematical model to predict oxygen transfer rates in hollow fiber membrane oxygenators
- Author
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S N, Vaslef, L F, Mockros, R W, Anderson, and R J, Leonard
- Subjects
Oxygen ,Hematocrit ,Linear Models ,Animals ,Cattle ,Equipment Design ,Models, Biological ,Blood Flow Velocity ,Oxygenators, Membrane - Abstract
A semi-empirical theoretical model of oxygen transfer is used to predict the rates of oxygen transfer to blood in hollow fiber membrane oxygenators over a wide range of inlet conditions. The predicted oxygen transfer rates are based on performance of the devices with water, which is more cost effective and easier to handle than blood for in vitro evaluations. Water experiments were conducted at three different flow rates to evaluate oxygen transfer performance in three commercially available membrane oxygenators. Data obtained from these experiments were used in a computer model to predict the rate of oxygen transfer to bovine blood at specified inlet conditions. Blood experiments were conducted at three different flow rates at a wide variety of inlet conditions, including different pH levels, hemoglobin concentrations, and oxyhemoglobin saturations for the three types of oxygenators. The measured and predicted oxygen transfer rates are closely correlated, which suggests that we have an accurate, reliable method for predicting oxygen transfer in hollow fiber membrane lungs.
- Published
- 1994
35. PD06-05: Primary and Secondary Pegfilgrastim Utilization in Adjuvant Chemotherapy for Breast Cancer in the Community
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M.A. Neubauer, R. W. Anderson, Leslie T. Busby, Janet L. Espirito, Roy A. Beveridge, Barry Don Brooks, Debra A. Patt, Brian Turnwald, John Russell Hoverman, and Michael Kolodziej
- Subjects
Oncology ,Cancer Research ,medicine.medical_specialty ,business.industry ,AD Regimen ,medicine.disease ,Surgery ,Clinical trial ,Regimen ,Breast cancer ,Docetaxel ,Internal medicine ,medicine ,Adjuvant therapy ,business ,Febrile neutropenia ,Pegfilgrastim ,medicine.drug - Abstract
Background Various factors are taken into consideration in the selection of adjuvant breast cancer (BC) chemotherapy (CT) regimens for patients. Choice of CT, schedule, duration, and supportive care affects costs and toxicity. Understanding clinical practice utilization patterns are important when making cost estimates of adjuvant therapy. Because pegfilgrastim is a large driver of cost it is important to understand the utilization characteristics. We aimed to characterize primary and secondary pegfilgrastim use during neoadjuvant/adjuvant (N/Ad) chemotherapy by regimen type. While initial data suggests the incidence of febrile neutropenia (FN) is low among some docetaxel containing regimens, we wanted to further characterize pegfilgrastim utilization, as previous utilization studies suggested it was higher than expected. Methods: Using the US Oncology iKnowMed™ EHR database, we retrospectively identified female BC patients (pts) diagnosed with stage I-III BC, between 7/2006 and 11/2010. Secondary diagnoses were excluded. Pts were characterized by age, ER and HER2 status, tumor size, grade, and nodes. CT utilization was determined by the number of pts assigned an N/Ad line of therapy (LOT) during the study period. Regimens were categorized by CT title and drugs. Clinical trial pts were included. Pegfilgrastim utilization was characterized if administered within 6 months of being assigned to an N/Ad CT regimen, and was captured as primary prophylaxis if the first dose was administered 5days. Results: General chemotherapy and pegfilgrastim utilization characteristics were previously reported. This report captures primary vs. secondary pegfilgrastim use. During the time period, 40,881 BC pts were identified. Of these, 15,328 pts (37%) were assigned an N/Ad CT regimen and 72% (11, 022 pts) received pegfilgrastim at any time within 6 months of their N/Ad regimen. Docetaxel containing regimens (TC, TAC, TCH) and dose-dense regimens accounted for the majority of all pegfilgrastim use. Pegfilgrastim utilization with the TC regimen was 70%, and represented 25% of all N/Ad pegfilgrastim utilization. The vast majority of utilization for TC and TCH was primary prophylaxis as detailed below: Conclusions: While primary prophylaxis in regimens like dose-dense AC and TAC are expected, the primary utilization of pegfilgrastim in TC and TCH is higher than expected based on published clinical trial experience. The incidence of FN has been reported at 5% in the clinical trial by Jones et al with TC, however subsequent reports suggest the incidence of FN may be higher than expected. Our results demonstrate high primary prophylaxis utilization adoption in clinical practice. With the availability of generic docetaxel, commonly used drugs in adjuvant BC except trastuzumab have generic equivalents. Pegfilgrastim will be the largest cost driver in women receiving adjuvant chemotherapy and should be considered among cost estimates. This study may underestimate utilization of pegfilgrastim if it was administered outside of the cancer center. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr PD06-05.
- Published
- 2011
- Full Text
- View/download PDF
36. Utilization of pegfilgrastim in adjuvant chemotherapy regimens for breast cancer in the community
- Author
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Janet L. Espirito, Michael Kolodziej, Brian Turnwald, US Oncology Pathways Task Force, Leslie T. Busby, Marcus A. Neubauer, John Russell Hoverman, Debra A. Patt, Roy A. Beveridge, R. W. Anderson, and Barry Don Brooks
- Subjects
Oncology ,Cancer Research ,medicine.medical_specialty ,Chemotherapy ,business.industry ,medicine.medical_treatment ,macromolecular substances ,medicine.disease ,Surgery ,Clinical trial ,Regimen ,Breast cancer ,Internal medicine ,medicine ,Adjuvant therapy ,Stage (cooking) ,business ,Adjuvant ,Pegfilgrastim ,medicine.drug - Abstract
213 Background: Selection of adjuvant breast cancer (BC) therapy varies based on patient risk factors. Choice of chemotherapy (CT), schedule, duration, and supportive care affects costs and toxicity. Because pegfilgrastim (PEG) is a large driver of cost in adjuvant therapy it is important to understand the utilization characteristics. We aimed to characterize PEG utilization during neoadjuvant/adjuvant (N/Ad) CT by age and regimen type. Methods: Using the US Oncology iKnowMed EHR database, we retrospectively identified female BC patients (pts) diagnosed with stage I-III BC, between 7/2006 and 11/2010. Secondary diagnoses were excluded. Pts were characterized by age, ER and HER2 status, tumor size, grade, and nodes. CT utilization was determined by the number of pts assigned an N/Ad line of therapy (LOT) during the study period. Regimens were categorized by CT title and drugs. Clinical trial pts were included. PEG utilization was characterized if administered within 6 months of being assigned to an N/Ad CT regimen. Results: During the time period, 40,881 newly diagnosed localized BC pts were identified. Of these, 15,328 pts (37%) were assigned an N/Ad CT regimen and 72% (11, 022 pts) received PEG at any time within 6 months of their N/Ad CT. When analyzed by regimen type, TC, TAC, TCH, and dose-dense AC-paclitaxel were the most highly utilized regimens accounting for 64% of all PEG use. PEG use with the TC regimen was 70% and represented 25% of all N/Ad PEG utilization. PEG utilization by age was characterized as 81% of pts Conclusions: While 37% of women treated in the N/Ad setting received CT, PEG was given to 72% of that subset. Utilization was high among all age groups. Dose-dense and docetaxel-containing regimens accounted for the majority of PEG use. With availability of generic docetaxel, commonly used drugs in adjuvant BC except trastuzumab will have generic equivalents and PEG will be the largest cost driver in women receiving adjuvant CT in the community. Since febrile neutropenia occurred in 5% of pts on the original TC trial, determination of appropriate level of use of PEG in the adjuvant setting needs further study.
- Published
- 2011
- Full Text
- View/download PDF
37. 9152 POSTER Comparative Value of Various Chemotherapy Regimens in 1st-line Treatment of Adenocarcinoma of the Lung
- Author
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Michael Kolodziej, S.R. Sheth, M. Clayton, M.A. Neubauer, R. W. Anderson, Roy A. Beveridge, and John Russell Hoverman
- Subjects
Oncology ,Cancer Research ,medicine.medical_specialty ,Chemotherapy ,business.industry ,medicine.medical_treatment ,medicine.disease ,Internal medicine ,medicine ,Adenocarcinoma of the lung ,Line (text file) ,business ,Value (mathematics) - Published
- 2011
- Full Text
- View/download PDF
38. Utilization and relative value of breast cancer adjuvant chemotherapy regimens in the community
- Author
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R. W. Anderson, John Russell Hoverman, Brian Turnwald, Barry Don Brooks, Roy A. Beveridge, Aimee Ginsburg, Michael Kolodziej, Janet L. Espirito, Greg C. Nelson, Marcus A. Neubauer, Thomas H. Cartwright, Mark A. Sitarik, M. Clayton, Sheetal Sheth, Jody S. Garey, Leslie T. Busby, and Debra A. Patt
- Subjects
Oncology ,Cancer Research ,Chemotherapy ,medicine.medical_specialty ,Relative value ,Adjuvant chemotherapy ,business.industry ,medicine.medical_treatment ,Patient risk ,medicine.disease ,Breast cancer ,Internal medicine ,medicine ,Intensive care medicine ,business ,Adjuvant - Abstract
e16595 Background: Selection of adjuvant breast cancer (BC) therapy varies based on patient risk factors. Utilization and choice of chemotherapy (CT), schedule, duration, and supportive care affect...
- Published
- 2011
- Full Text
- View/download PDF
39. Understanding male breast cancer in the community setting
- Author
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Marcus A. Neubauer, Michael Kolodziej, Roy A. Beveridge, J. Flinn, Aimee Ginsburg, Thomas H. Cartwright, Leslie T. Busby, John Russell Hoverman, R. W. Anderson, Mark A. Sitarik, Barry Don Brooks, Debra A. Patt, US Oncology Pathways Task Force, and Janet L. Espirito
- Subjects
Gynecology ,Cancer Research ,medicine.medical_specialty ,Obstetrics ,business.industry ,medicine.disease ,Breast cancer ,Oncology ,Male breast cancer ,medicine ,Community setting ,Male population ,skin and connective tissue diseases ,business - Abstract
e16526 Background: Male breast cancer (BC) affects
- Published
- 2011
- Full Text
- View/download PDF
40. Bevacizumab therapy in advanced non-small cell lung cancer (NSCLC): Outcomes from a community oncology network
- Author
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Thomas H. Cartwright, R. W. Anderson, Jody S. Garey, Roy A. Beveridge, Michael Kolodziej, Leslie T. Busby, Barry Don Brooks, Greg C. Nelson, Mark A. Sitarik, US Oncology Pathways Task Force, Marcus A. Neubauer, Debra A. Patt, and John Russell Hoverman
- Subjects
Oncology ,Cancer Research ,medicine.medical_specialty ,Bevacizumab ,business.industry ,non-small cell lung cancer (NSCLC) ,medicine.disease ,Carboplatin ,chemistry.chemical_compound ,Paclitaxel ,chemistry ,Internal medicine ,medicine ,business ,neoplasms ,medicine.drug - Abstract
e16527 Background: Bevacizumab (B) was FDA-approved in 2004 in combination with carboplatin and paclitaxel (CP) for treatment of first-line metastatic NSCLC after a phase III trial was conducted sh...
- Published
- 2011
- Full Text
- View/download PDF
41. Evaluation of air quality in a sterile-drug preparation area with an electronic particle counter
- Author
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S W, Chandler, L A, Trissel, L M, Wamsley, J D, Lajeunesse, and R W, Anderson
- Subjects
Quality Control ,Evaluation Studies as Topic ,Air Pollution, Indoor ,Chemistry, Pharmaceutical ,Drug Compounding ,Humans ,Sterilization ,Cancer Care Facilities ,Pharmacy Service, Hospital ,Texas - Abstract
The air quality in a sterile-drug preparation area was assessed with an electronic particle counter. The numbers of airborne particles ofor = 0.5 and5 microns in a hospital i.v. room were determined. Initially, a total of seven sampling sites were designated; the four locations and four times with the highest concentrations of particles were analyzed. To determine the classification of the cleanroom, as described in Federal Standard 209E (FS209E), four equally spaced locations in the room were examined on one day. According to FS209E, the average concentration of particles in samples obtained at each of four locations uniformly spaced in a room must beor = 100,000 per cubic foot of sampled air for particles ofor = 0.5 micron in order for a room to qualify as a Class 100,000 cleanroom. Throughout the seven-day initial study, all measurements of particles ofor = 0.5 micron except one yielded counts of100,000/cu ft. The four highest average particle concentrations were recorded at 1000, 1100, 1400, and 1500. Although measurement of particles of5 microns was not necessary, the measurements of these particles showed that their concentrations were highly dependent on staff activity. The average particle concentration at the four equally spaced locations was36,000/cu ft. At the four locations, the mean of the average concentrations was 29,664 particles per cubic foot. The upper limit of the 95% confidence interval for particle concentration at the four locations was 35,896/cu ft.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1993
42. Indoor air is nearly cleanroom quality
- Author
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L A, Trissel, S W, Chandler, and R W, Anderson
- Subjects
Drug Compounding ,Sterilization ,Environment, Controlled ,Pharmacy Service, Hospital - Published
- 1993
43. Laser ray tracing in a parallel arbitrary Lagrangian-Eulerian adaptive mesh refinement hydrocode
- Author
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T B Kaiser, R W Anderson, Alice Koniges, D. C. Eder, Aaron Fisher, and N. Masters
- Subjects
Physics ,History ,Traverse ,Adaptive mesh refinement ,law ,Ray tracing (graphics) ,Laser ,Arbitrary lagrangian eulerian ,Computer Science Applications ,Education ,law.invention ,Computational science - Abstract
ALE-AMR is a new hydrocode that we are developing as a predictive modeling tool for debris and shrapnel formation in high-energy laser experiments. In this paper we present our approach to implementing laser ray tracing in ALE-AMR. We present the basic concepts of laser ray tracing and our approach to eciently traverse the adaptive mesh hierarchy.
- Published
- 2010
- Full Text
- View/download PDF
44. Assessment and mitigation of radiation, EMP, debris & shrapnel impacts at megajoule-class laser facilities
- Author
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A Throop, A Geille, Aaron Fisher, O. S. Jones, C. S. Debonnel, T. J. Clancy, C. G. Brown, Otto Landen, Andrew MacPhee, J. R. Kimbrough, P Song, R. Tommasini, Alice Koniges, Pamela K. Whitman, Daniel H. Kalantar, J. Raimbourg, Perry M. Bell, R W Anderson, Andrea L. Bertozzi, M L Stowell, Joseph Teran, W Bittle, Hesham Khater, N. Masters, Stanley Osher, J. P. Holder, V. Rekow, B. J. MacGowan, D. K. Bradley, C. Stoeckl, J. P. Jadaud, P. Combis, D S Bailey, Brian Maddox, David J. Benson, Mark Eckart, Vladimir Glebov, J. Vierne, H. Chen, D. C. Eder, C. Sangster, Marc A. Meyers, Lucile S. Dauffy, J.-M. Chevalier, R. Prasad, D. Raffestin, T B Kaiser, and Daniel A. White
- Subjects
History ,Materials science ,business.industry ,Nuclear engineering ,Electrical engineering ,Radiation ,Laser ,Debris ,Computer Science Applications ,Education ,law.invention ,law ,Neutron ,business ,Electromagnetic pulse - Abstract
The generation of neutron/gamma radiation, electromagnetic pulses (EMP), debris and shrapnel at mega-Joule class laser facilities (NIF and LMJ) impacts experiments conducted at these facilities. The complex 3D numerical codes used to assess these impacts range from an established code that required minor modifications (MCNP - calculates neutron and gamma radiation levels in complex geometries), through a code that required significant modifications to treat new phenomena (EMSolve - calculates EMP from electrons escaping from laser targets), to a new code, ALE-AMR, that is being developed through a joint collaboration between LLNL, CEA, and UC (UCSD, UCLA, and LBL) for debris and shrapnel modelling.
- Published
- 2010
- Full Text
- View/download PDF
45. Modeling heat conduction and radiation transport with the diffusion equation in NIF ALE-AMR
- Author
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Aaron Fisher, Brian T. N. Gunney, T B Kaiser, N. Masters, Alice Koniges, D. C. Eder, D S Bailey, and R W Anderson
- Subjects
Radiation transport ,Physics ,History ,Diffusion equation ,Adaptive mesh refinement ,Composite mesh ,Large range ,Mechanics ,Thermal conduction ,Arbitrary lagrangian eulerian ,Computer Science Applications ,Education ,Radiative transport ,Statistical physics - Abstract
The ALE-AMR code developed for NIF is a multi-material hydro-code that models target assembly fragmentation in the aftermath of a shot. The combination of ALE (Arbitrary Lagrangian Eulerian) hydro with AMR (Adaptive Mesh Refinement) allows the code to model a wide range of physical conditions and spatial scales. The large range of temperatures encountered in the NIF target chamber can lead to significant fluxes of energy due to thermal conduction and radiative transport. These physical effects can be modeled approximately with the aid of the diffusion equation. We present a novel method for the solution of the diffusion equation on a composite mesh in order to capture these physical effects.
- Published
- 2010
- Full Text
- View/download PDF
46. ALE-AMR: A new 3D multi-physics code for modeling laser/target effects
- Author
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T B Kaiser, F Hansen, Brian T. N. Gunney, P Wang, R W Anderson, Aaron Fisher, N. Masters, David J. Benson, Marc A. Meyers, Alice Koniges, K Fisher, A Geille, D. C. Eder, B Brown, D S Bailey, and Brian Maddox
- Subjects
Physics ,Coalescence (physics) ,History ,Adaptive mesh refinement ,Solver ,Plasticity ,Spall ,Thermal conduction ,Laser ,Computer Science Applications ,Education ,Computational science ,law.invention ,law ,Persistent data structure ,Simulation - Abstract
We have developed a new 3D multi-physics multi-material code, ALE- AMR, for modeling laser/target effects including debris/shrapnel generation. The code combines Arbitrary Lagrangian Eulerian (ALE) hydrodynamics with Adaptive Mesh Refinement (AMR) to connect the continuum to microstructural regimes. The code is unique in its ability to model hot radiating plasmas and cold fragmenting solids. New numerical techniques were developed for many of the physics packages to work efficiency on a dynamically moving and adapting mesh. A flexible strength/failure framework allows for pluggable material models. Material history arrays are used to store persistent data required by the material models, for instance, the level of accumulated damage or the evolving yield stress in J2 plasticity models. We model ductile metals as well as brittle materials such as Si, Be, and B4C. We use interface reconstruction based on volume fractions of the material components within mixed zones and reconstruct interfaces as needed. This interface reconstruction model is also used for void coalescence and fragmentation. The AMR framework allows for hierarchical material modeling (HMM) with different material models at different levels of refinement. Laser rays are propagated through a virtual composite mesh consisting of the finest resolution representation of the modeled space. A new 2 nd order accurate diffusion solver has been implemented for the thermal conduction and radiation transport packages. The code is validated using laser and x-ray driven spall experiments in the US and France. We present an overview of the code and simulation results.
- Published
- 2010
- Full Text
- View/download PDF
47. Harvey A. K. Whitney Lecture. Of perceived value
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R W, Anderson
- Subjects
Societies, Pharmaceutical ,Pharmacy Administration ,Awards and Prizes ,Pharmacy Technicians ,Internship, Nonmedical ,Education, Pharmacy, Graduate ,Pharmacy ,History, 20th Century ,United States ,Patient Education as Topic ,Education, Pharmacy ,History of Pharmacy ,Pharmaceutical Services ,Humans ,Institutional Practice - Abstract
Current issues in pharmacy are discussed and recommendations are made to help pharmacy demonstrate its value in health care. There is a need for pharmacy to actively demonstrate and communicate its value in health care. Educational requirements should reflect the values of the profession. In the debate over the entry-level Pharm.D. degree, the profession must not lose sight of the principal goal of elevating the basic competencies of all pharmacists. Graduate-level education will continue to be valuable, but the degrees and programs should be modified to meet current and future needs. Residency training will become increasingly essential. A well-defined corps of pharmacy technicians is needed. The profession should strive to meet the needs of society rather than confining itself to traditional practice definitions. This will involve increased interaction with patients. Also, pharmacy directors must become more creative in allocating existing resources and building arguments for expansion. When patients recognize the value of pharmacy services, they will seek out and demand those services. Pharmacists must get involved in deliberations regarding health-care reform. They have a responsibility to promote preventive medicine and healthy life-styles. They should actively promote the rational use of all medications. Although tremendous progress has been made in advancing the concept of pharmaceutical care, the profession still has work to do in communicating its value to the public.
- Published
- 1992
48. Medications and temporaries in endodontic treatment
- Author
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S, Madison and R W, Anderson
- Subjects
Root Canal Filling Materials ,Root Canal Irrigants ,Dental Cements ,Humans ,Root Canal Therapy - Abstract
We have attempted to present in this article an overview of the medications used as intracanal dressings during root canal treatment and the materials used to seal endodontic access preparations. Because all the medications reviewed have an antimicrobial effect (with the exception of steroids), they seemingly would be useful in root canal treatment. However, the potentially harmful side effects of the chemical agents, which include cytotoxicity and antigenicity, may make the treatment worse than the cure. With an improved understanding of the principles of root canal cleaning, strong medications placed into canals may be unnecessary. At best, intracanal dressings should be used only in situations that might benefit from such therapy. Temporary restoration of endodontically treated teeth is an essential part of root canal therapy. Commonly used materials and techniques for their uses have been presented. With proper temporization and timely final restoration, the potential for coronal microleakage will be minimized.
- Published
- 1992
49. Pharmacists' knowledge of infusion devices
- Author
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J W, Kwan and R W, Anderson
- Subjects
Patients ,Humans ,Hospitals, Community ,Infusions, Intravenous ,Pharmacists ,Pharmacy Service, Hospital ,Home Care Services - Abstract
Results of a mail survey of pharmacists' knowledge of infusion-device technology are presented. In order to develop recommendations on how to prepare pharmacists to take responsible roles in the use of infusion devices, a survey was mailed to 576 directors of pharmacy in hospitals and home health-care companies, deans of pharmacy schools, and executives of state pharmaceutical associations. A total of 237 responses (41.2%) was received. Directors in both hospital and home health-care settings predicted increases in the use of infusion devices in their respective settings within the coming five years. Practitioners and deans concurred that pharmacy schools are not providing adequate instruction in the use of these devices. All four groups of respondents believed that the competencies most essential in the use of these devices are knowledge of therapeutic applications and the ability to select the most appropriate pump to meet clinical needs. Use of drug-infusion technology will increase in the coming five years, and undergraduate, postgraduate, and inservice pharmacy curricula must prepare pharmacists to use it appropriately.
- Published
- 1991
50. Hospital administrators' perceptions of pharmacy directors
- Author
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E D, Raiford, T, Clark, and R W, Anderson
- Subjects
Interdepartmental Relations ,Professional Competence ,Pharmacy Administration ,Attitude of Health Personnel ,Surveys and Questionnaires ,Humans ,Hospital Administrators ,Pharmacists ,Pharmacy Service, Hospital ,United States - Abstract
The results of a national survey of hospital administrators' perceptions of pharmacy directors are reported. A questionnaire was mailed to a random sample of 1000 hospital administrators nationwide. The questionnaire asked each administrator to rate the managerial skills of pharmacy directors in general and the pharmacy director at his or her institution on a 5-point scale. The value the administrator placed on clinical pharmacy services was investigated, as was the administrator's knowledge of the education of the pharmacy director and the reporting structure between administrator and pharmacy director. The net response rate was 47.8% (478 usable replies). The hospital administrators believed that pharmacy directors in general need to improve their relationship with the nursing staff, their basic managerial skills, and their communication skills. They believed that the pharmacy director at their own institution excelled at keeping up with progressive pharmacy practice, inventory management, and interacting with the pharmacy and therapeutics committee. The administrators indicated that it is very important for the pharmacy department to be involved in therapeutic drug monitoring and medication counseling and to be progressive in their offerings of services. Hospital administrators had a positive perception of the abilities of pharmacy directors but believed that there is still room for improvement.
- Published
- 1991
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