National Library of Energy BETA

Sample records for dynamic optimization model

  1. Nonlinear Hybrid Dynamical Systems: Modeling, Optimal Control, and Applications

    E-Print Network [OSTI]

    Stryk, Oskar von

    Nonlinear Hybrid Dynamical Systems: Modeling, Optimal Control, and Applications Martin Buss1¨unchen, Germany Abstract. Nonlinear hybrid dynamical systems are the main focus of this paper. A modeling Introduction The recent interest in nonlinear hybrid dynamical systems has forced the merger of two very

  2. A Nonlinear Continuous Time Optimal Control Model of Dynamic Pricing and Inventory Control with no

    E-Print Network [OSTI]

    Adida, Elodie

    time optimal control model for studying a dynamic pricing and inventory control problem for a make-to-stock of not introducing any approximation to the real setting: it provides the exact solution of the system. When taking

  3. Event-driven multithreaded dynamic optimization

    E-Print Network [OSTI]

    Zhang, Weifeng

    2006-01-01

    Speci?c Optimizations . . . . . . . . . . . . . F.3. Trace Optimization Overhead . . . . . . . . . . . . . . .Dynamic Optimization . . . . . . .B. Optimizations with the

  4. Optimization models in finance Ma 450 Darinka Dentcheva Fall 2014 darinka.dentcheva@stevens.edu

    E-Print Network [OSTI]

    Dentcheva, Darinka

    Optimization models in finance Ma 450 Darinka Dentcheva Fall 2014 darinka and dynamic optimization problems occurring in finance. We shall discuss linear and non-linear optimization models of finance, dynamic (sequential) optimization, optimization under uncertainty, mathematical models

  5. Tools for dynamic model development

    E-Print Network [OSTI]

    Schaber, Spencer Daniel

    2014-01-01

    For this thesis, several tools for dynamic model development were developed and analyzed. Dynamic models can be used to simulate and optimize the behavior of a great number of natural and engineered systems, from the ...

  6. Identification of Hybrid Dynamical Models of Human Movement via Switched System Optimal Control

    E-Print Network [OSTI]

    Vasudevan, Ramanarayan

    2012-01-01

    of constrained nonlinear switched dynamical systems. Inconstrained nonlinear switched dynamical systems is devised.

  7. An Infrastructure for Adaptive Dynamic Optimization

    E-Print Network [OSTI]

    Amarasinghe, Saman

    An Infrastructure for Adaptive Dynamic Optimization Derek Bruening, Timothy Garnett, and Saman,timothyg,saman}@lcs.mit.edu Abstract Dynamic optimization is emerging as a promising ap- proach to overcome many of the obstacles static optimizations, there are very few for developing dynamic optimizations. We present a framework

  8. Natural Dynamics for Combinatorial Optimization

    E-Print Network [OSTI]

    Ovchinnikov, Igor V

    2015-01-01

    Stochastic and or natural dynamical systems (DSs) are dominated by sudden nonlinear processes such as neuroavalanches, gamma-ray bursts, solar flares, earthquakes etc. that exhibit scale-free statistics. These behaviors also occur in many nanosystems. On phase diagrams, these DSs belong to a finite-width phase that separates the phases of thermodynamic equilibrium and ordinary chaotic dynamics, and that is known under such names as intermittency, noise-induced chaos, and self-organized criticality. Within the recently formulated approximation-free cohomological theory of stochastic differential equations, the noise-induced chaos can be roughly interpreted as a noise-induced overlap between regular (integrable) and chaotic (non-integrable) deterministic dynamics so that DSs in this phase inherit the properties of the both. Here, we analyze this unique set of properties and conclude that such DSs must be the most efficient natural optimizers. Based on this understanding, we propose the method of the natural dyn...

  9. Real-time Dynamic Optimization of Batch Crystallization Processes

    E-Print Network [OSTI]

    Van den Hof, Paul

    process. The seeded fed-batch crystallizer is represented by a nonlinear moment model. An optimal controlReal-time Dynamic Optimization of Batch Crystallization Processes Ali Mesbah, , Alex N. Kalbasenka-time implementations of the proposed strategy reveal the effectiveness of closed-loop optimal control

  10. Dynamic Portfolio Optimization with Transaction Costs: Heuristics ...

    E-Print Network [OSTI]

    2011-02-03

    Aug 10, 2010 ... Dynamic Portfolio Optimization with Transaction. Costs: Heuristics and Dual Bounds. David B. Brown and James E. Smith?. Fuqua School of ...

  11. Hierarchical Dynamic Models

    E-Print Network [OSTI]

    Penny, Will

    Hierarchical Dynamic Models Will Penny OU Processes Embedding OU(2) process Dynamic Models Hierarchical Dynamic Models Will Penny 26th May 2011 #12;Hierarchical Dynamic Models Will Penny OU Processes Dynamic Models Will Penny OU Processes Embedding OU(2) process Dynamic Models Generalised coordinates

  12. HOMER® Micropower Optimization Model

    SciTech Connect (OSTI)

    Lilienthal, P.

    2005-01-01

    NREL has developed the HOMER micropower optimization model. The model can analyze all of the available small power technologies individually and in hybrid configurations to identify least-cost solutions to energy requirements. This capability is valuable to a diverse set of energy professionals and applications. NREL has actively supported its growing user base and developed training programs around the model. These activities are helping to grow the global market for solar technologies.

  13. DYNAMIC RISK MANAGEMENT IN ELECTRICITY PORTFOLIO OPTIMIZATION

    E-Print Network [OSTI]

    Römisch, Werner

    DYNAMIC RISK MANAGEMENT IN ELECTRICITY PORTFOLIO OPTIMIZATION VIA POLYHEDRAL RISK FUNCTIONALS the dynamic decision structure appropriately. In energy risk management, which is typically carried out ex, for integrating risk management into a stochastic optimization framework, risk has to be quantified in a definite

  14. Optimal signal patterns for dynamical cellular communication

    E-Print Network [OSTI]

    Hasegawa, Yoshihiko

    2015-01-01

    Cells transmit information via signaling pathways, using temporal dynamical patterns. As optimality with respect to environments is the universal principle in biological systems, organisms have acquired an optimal way of transmitting information. Here we obtain optimal dynamical signal patterns which can transmit information efficiently (low power) and reliably (high accuracy) using the optimal control theory. Adopting an activation-inactivation decoding network, we reproduced several dynamical patterns found in actual signals, such as steep, gradual and overshooting dynamics. Notably, when minimizing the power of the input signal, optimal signals exhibit the overshooting pattern, which is a biphasic pattern with transient and steady phases; this pattern is prevalent in actual dynamical patterns as it can be generated by an incoherent feed-forward loop (FFL), a common motif in biochemical networks. We also identified conditions when the three patterns, steep, gradual and overshooting, confer advantages.

  15. MODEL-BASED OPTIMAL OPERATION OF SEEDED BATCH CRYSTALLISATION PROCESSES

    E-Print Network [OSTI]

    Van den Hof, Paul

    .mesbah@tudelft.nl Dynamic optimization is applied for optimal control of a semi-industrial batch crystallisation process of the open-loop optimal control due to plant-model mismatch, unmeasured process disturbances, irreproducibleMODEL-BASED OPTIMAL OPERATION OF SEEDED BATCH CRYSTALLISATION PROCESSES A. Mesbah1, 2 , J. Landlust

  16. Dynamic Optimization for Optimal Control of Water Distribution Systems

    E-Print Network [OSTI]

    Ertin, Emre

    Dynamic Optimization for Optimal Control of Water Distribution Systems Emre Ertin, Anthony N. Dean Columbus OH 43201 ABSTRACT In this paper we consider the design of intelligent control policies for water as a controller for a water distribution system. In the example presented we obtain a 12.5 percent reduction

  17. TRACKING CODE DEVELOPMENT FOR BEAM DYNAMICS OPTIMIZATION

    SciTech Connect (OSTI)

    Yang, L.

    2011-03-28

    Dynamic aperture (DA) optimization with direct particle tracking is a straight forward approach when the computing power is permitted. It can have various realistic errors included and is more close than theoretical estimations. In this approach, a fast and parallel tracking code could be very helpful. In this presentation, we describe an implementation of storage ring particle tracking code TESLA for beam dynamics optimization. It supports MPI based parallel computing and is robust as DA calculation engine. This code has been used in the NSLS-II dynamics optimizations and obtained promising performance.

  18. Online optimization of storage ring nonlinear beam dynamics ...

    Office of Scientific and Technical Information (OSTI)

    Online optimization of storage ring nonlinear beam dynamics Citation Details In-Document Search Title: Online optimization of storage ring nonlinear beam dynamics Authors: Huang,...

  19. Online optimization of storage ring nonlinear beam dynamics ...

    Office of Scientific and Technical Information (OSTI)

    Online optimization of storage ring nonlinear beam dynamics Citation Details In-Document Search Title: Online optimization of storage ring nonlinear beam dynamics You are...

  20. Optimization of the dynamic behavior of strongly nonlinear heterogeneous materials

    E-Print Network [OSTI]

    Herbold, Eric B.

    2008-01-01

    dissimilar granular materials) and for optimization of shockOptimization of Dynamic Behavior in Heterogeneous Materials (band-gap materials and structures by topology optimization.

  1. An Optimization Framework for Dynamic Hybrid Energy Systems

    SciTech Connect (OSTI)

    Wenbo Du; Humberto E Garcia; Christiaan J.J. Paredis

    2014-03-01

    A computational framework for the efficient analysis and optimization of dynamic hybrid energy systems (HES) is developed. A microgrid system with multiple inputs and multiple outputs (MIMO) is modeled using the Modelica language in the Dymola environment. The optimization loop is implemented in MATLAB, with the FMI Toolbox serving as the interface between the computational platforms. Two characteristic optimization problems are selected to demonstrate the methodology and gain insight into the system performance. The first is an unconstrained optimization problem that optimizes the dynamic properties of the battery, reactor and generator to minimize variability in the HES. The second problem takes operating and capital costs into consideration by imposing linear and nonlinear constraints on the design variables. The preliminary optimization results obtained in this study provide an essential step towards the development of a comprehensive framework for designing HES.

  2. DYNAMIC RISK MANAGEMENT IN ELECTRICITY PORTFOLIO OPTIMIZATION

    E-Print Network [OSTI]

    Eichhorn, Andreas

    DYNAMIC RISK MANAGEMENT IN ELECTRICITY PORTFOLIO OPTIMIZATION VIA POLYHEDRAL RISK FUNCTIONALS production and trading based on probabilistic knowledge about future uncertainties such as demands and spot- called polyhedral risk functionals which, though being non-linear mappings, preserve linearity structures

  3. Global Dynamic Optimization Adam Benjamin Singer

    E-Print Network [OSTI]

    in Chemical Engineering Abstract My thesis focuses on global optimization of nonconvex integral objectiveGlobal Dynamic Optimization by Adam Benjamin Singer Submitted to the Department of Chemical Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemical

  4. Unified Particle Swarm Optimization in Dynamic Environments

    E-Print Network [OSTI]

    Parsopoulos, Konstantinos

    Introduction Particle Swarm Optimization (PSO) is a stochastic optimization algorithm that belongs to the category of swarm intelligence methods [1,2]. PSO has attained in- creasing popularity due to its ability a thorough investigation of PSO on a large number of dynamic test problems. Modifications of PSO that can

  5. Proportional Integral Distributed Optimization for Dynamic Network Topologies

    E-Print Network [OSTI]

    Egerstedt, Magnus

    Proportional Integral Distributed Optimization for Dynamic Network Topologies Greg Droge, Magnus Egerstedt Abstract--This paper investigates proportional-integral distributed optimization when the underlying informa- tion exchange network is dynamic. Proportional-integral distributed optimization

  6. Stochastic Optimization Modeling

    E-Print Network [OSTI]

    2014-07-04

    Third, its theoretical properties were studied (convexity, separability and optimality con- .... in Section 3, have the structure of problems PEV and PS, respectively, and for this reason we review ... may produce poor optimization results as it is depicted in Figure 1 for the instance with ...... Second, it has been assessed that the.

  7. February 15, 2006 Dynamic Optimization for

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    with A+ models · Dow/MDC/Emerson - RTO of system of 4 cogeneration plants, optimization run every 30 min,000 variables and equations) 1986 - Shell Opera package for ethylene plants 1988 - First DMO application, Sunoco://www.arcweb.com/research/ent/rpo.asp for industry assessment 6 #12;Some Recent RTO Studies · Agrium - optimization of integrated NH3 plant, 1

  8. IMPACT OF DYNAMIC VOLTAGE SCALING (DVS) ON CIRCUIT OPTIMIZATION 

    E-Print Network [OSTI]

    Esquit Hernandez, Carlos A.

    2010-01-16

    Circuit designers perform optimization procedures targeting speed and power during the design of a circuit. Gate sizing can be applied to optimize for speed, while Dual-VT and Dynamic Voltage Scaling (DVS) can be applied to optimize for leakage...

  9. One-Dimensional Infinite Horizon Nonconcave Optimal Control Problems Arising in Economic Dynamics

    SciTech Connect (OSTI)

    Zaslavski, Alexander J., E-mail: ajzasl@tx.technion.ac.il [Technion-Israel Institute of Technology, Department of Mathematics (Israel)

    2011-12-15

    We study the existence of optimal solutions for a class of infinite horizon nonconvex autonomous discrete-time optimal control problems. This class contains optimal control problems without discounting arising in economic dynamics which describe a model with a nonconcave utility function.

  10. Dynamic cable analysis models

    SciTech Connect (OSTI)

    Palo, P.A.; Meggitt, D.J.; Nordell, W.J.

    1983-05-01

    This paper presents a summary of the development and validation of undersea cable dynamics computer models by the Naval Civil Engineering Laboratory (NCEL) under the sponsorship of the Naval Facilities Engineering Command. These models allow for the analysis of both small displacement (strumming) and large displacement (static and dynamic) deformations of arbitrarily configured cable structures. All of the large displacement models described in this paper are available to the public. This paper does not emphasize the theoretical development of the models (this information is available in other references) but emphasizes the various features of the models, the comparisons between model output and experimental data, and applications for which the models have been used.

  11. Tensor-optimized antisymmetrized molecular dynamics in nuclear physics

    E-Print Network [OSTI]

    Myo, Takayuki; Ikeda, Kiyomi; Horiuchi, Hisashi; Suhara, Tadahiro

    2015-01-01

    We develop a new formalism to treat nuclear many-body systems using bare nucleon-nucleon interaction. It has become evident that the tensor interaction plays important role in nuclear many-body systems due to the role of the pion in strongly interacting system. We take the antisymmetrized molecular dynamics (AMD) as a basic framework and add a tensor correlation operator acting on the AMD wave function using the concept of the tensor-optimized shell model (TOSM). We demonstrate a systematical and straightforward formulation utilizing the Gaussian integration and differentiation method and the antisymmetrization technique to calculate all the matrix elements of the many-body Hamiltonian. We can include the three-body interaction naturally and calculate the matrix elements systematically in the progressive order of the tensor correlation operator. We call the new formalism "tensor-optimized antisymmetrized molecular dynamics".

  12. Optimization Modeling Languages Emmanuel Fragni`ere

    E-Print Network [OSTI]

    Gondzio, Jacek

    Optimization Modeling Languages Emmanuel Fragni`ere HEC, Department of Management, University, 1999 1 #12;Abstract The access to advanced optimization software needs more and more sophisticated modeling tools. Optimization modeling languages are tools that facilitate the decision making process based

  13. HOMER: The Micropower Optimization Model

    SciTech Connect (OSTI)

    Not Available

    2004-03-01

    HOMER, the micropower optimization model, helps users to design micropower systems for off-grid and grid-connected power applications. HOMER models micropower systems with one or more power sources including wind turbines, photovoltaics, biomass power, hydropower, cogeneration, diesel engines, cogeneration, batteries, fuel cells, and electrolyzers. Users can explore a range of design questions such as which technologies are most effective, what size should components be, how project economics are affected by changes in loads or costs, and is the renewable resource adequate.

  14. Integrated Dynamic Simulation for Process Optimization and Control

    E-Print Network [OSTI]

    Rubloff, Gary W.

    Integrated Dynamic Simulation for Process Optimization and Control G. Brian Lu, Laura L. Tedder ­ Film Deposition · Applications in Process Optimization for Manufacturing and the Environment ­ Process efficient processes, equipment, sensor, and control systems #12;Dynamic Simulators for Sensor-Based Process

  15. MODELING, SIMULATION AND OPTIMIZATION OF GROUND SOURCE

    E-Print Network [OSTI]

    MODELING, SIMULATION AND OPTIMIZATION OF GROUND SOURCE HEAT PUMP SYSTEMS By MUHAMMAD HAIDER KHAN AND OPTIMIZATION OF GROUND SOURCE HEAT PUMP SYSTEMS Thesis Approved..................................................................................................................... 1 1.1 Overview of Ground Source Heat Pump Systems.............................................. 1 1

  16. Modeling and optimization of permanent magnetic motors

    E-Print Network [OSTI]

    Pinkham, Andrew P

    2008-01-01

    This thesis develops analytic models for the prediction and optimization of radial-flux permanent magnet motor torque and efficiency. It also facilitates the design optimization of electromagnetically-powered rotorcraft ...

  17. Optimized Uncertainty Quantification Algorithm Within a Dynamic Event Tree Framework

    SciTech Connect (OSTI)

    J. W. Nielsen; Akira Tokuhiro; Robert Hiromoto

    2014-06-01

    Methods for developing Phenomenological Identification and Ranking Tables (PIRT) for nuclear power plants have been a useful tool in providing insight into modelling aspects that are important to safety. These methods have involved expert knowledge with regards to reactor plant transients and thermal-hydraulic codes to identify are of highest importance. Quantified PIRT provides for rigorous method for quantifying the phenomena that can have the greatest impact. The transients that are evaluated and the timing of those events are typically developed in collaboration with the Probabilistic Risk Analysis. Though quite effective in evaluating risk, traditional PRA methods lack the capability to evaluate complex dynamic systems where end states may vary as a function of transition time from physical state to physical state . Dynamic PRA (DPRA) methods provide a more rigorous analysis of complex dynamic systems. A limitation of DPRA is its potential for state or combinatorial explosion that grows as a function of the number of components; as well as, the sampling of transition times from state-to-state of the entire system. This paper presents a method for performing QPIRT within a dynamic event tree framework such that timing events which result in the highest probabilities of failure are captured and a QPIRT is performed simultaneously while performing a discrete dynamic event tree evaluation. The resulting simulation results in a formal QPIRT for each end state. The use of dynamic event trees results in state explosion as the number of possible component states increases. This paper utilizes a branch and bound algorithm to optimize the solution of the dynamic event trees. The paper summarizes the methods used to implement the branch-and-bound algorithm in solving the discrete dynamic event trees.

  18. On Using Complex Event Processing for Dynamic Demand Response Optimization in Microgrid

    E-Print Network [OSTI]

    Hwang, Kai

    On Using Complex Event Processing for Dynamic Demand Response Optimization in Microgrid Qunzhi Zhou Processing (CEP) patterns to model and detect dynamic situations in a campus microgrid to facilitate adaptive these patterns on realtime events in the USC Campus microgrid using our CEP framework. Index Terms

  19. Validated global multiobjective optimization of trajectories in nonlinear dynamical systems

    E-Print Network [OSTI]

    Coffee, Thomas Merritt

    2015-01-01

    We introduce a new approach for global multiobjective optimization of trajectories in continuous nonlinear dynamical systems that can provide rigorous, arbitrarily tight bounds on the objective values and state paths ...

  20. Dynamic Memory Usage Optimization using ILP and J. Ramanujam2

    E-Print Network [OSTI]

    Ramanujam, J. "Ram"

    Dept., Assiut University, Egypt 2 Electrical and Computer Engineering Dept, Louisiana State UniversityDynamic Memory Usage Optimization using ILP A. Allam1 and J. Ramanujam2 1 Electrical Engineering

  1. Progress on Optimization of the Nonlinear Beam Dynamics in the...

    Office of Scientific and Technical Information (OSTI)

    in the MEIC Collider Rings Citation Details In-Document Search Title: Progress on Optimization of the Nonlinear Beam Dynamics in the MEIC Collider Rings One of the key...

  2. First principles molecular dynamics without self-consistent field optimization

    SciTech Connect (OSTI)

    Souvatzis, Petros; Niklasson, Anders M. N.

    2014-01-28

    We present a first principles molecular dynamics approach that is based on time-reversible extended Lagrangian Born-Oppenheimer molecular dynamics [A. M. N. Niklasson, Phys. Rev. Lett. 100, 123004 (2008)] in the limit of vanishing self-consistent field optimization. The optimization-free dynamics keeps the computational cost to a minimum and typically provides molecular trajectories that closely follow the exact Born-Oppenheimer potential energy surface. Only one single diagonalization and Hamiltonian (or Fockian) construction are required in each integration time step. The proposed dynamics is derived for a general free-energy potential surface valid at finite electronic temperatures within hybrid density functional theory. Even in the event of irregular functional behavior that may cause a dynamical instability, the optimization-free limit represents a natural starting guess for force calculations that may require a more elaborate iterative electronic ground state optimization. Our optimization-free dynamics thus represents a flexible theoretical framework for a broad and general class of ab initio molecular dynamics simulations.

  3. Optimized dynamical control of state transfer through noisy spin chains

    E-Print Network [OSTI]

    Analia Zwick; Gonzalo A. Alvarez; Guy Bensky; Gershon Kurizki

    2015-01-09

    We propose a method of optimally controlling the tradeoff of speed and fidelity of state transfer through a noisy quantum channel (spin-chain). This process is treated as qubit state-transfer through a fermionic bath. We show that dynamical modulation of the boundary-qubits levels can ensure state transfer with the best tradeoff of speed and fidelity. This is achievable by dynamically optimizing the transmission spectrum of the channel. The resulting optimal control is robust against both static and fluctuating noise in the channel's spin-spin couplings. It may also facilitate transfer in the presence of diagonal disorder (on site energy noise) in the channel.

  4. Simple Dynamic Gasifier Model That Runs in Aspen Dynamics

    SciTech Connect (OSTI)

    Robinson, P.J.; Luyben, W.L. [Lehigh University, Bethlehem, PA (United States). Dept. of Chemical Engineering

    2008-10-15

    Gasification (or partial oxidation) is a vital component of 'clean coal' technology. Sulfur and nitrogen emissions can be reduced, overall energy efficiency is increased, and carbon dioxide recovery and sequestration are facilitated. Gasification units in an electric power generation plant produce a fuel for driving combustion turbines. Gasification units in a chemical plant generate gas, which can be used to produce a wide spectrum of chemical products. Future plants are predicted to be hybrid power/chemical plants with gasification as the key unit operation. The widely used process simulator Aspen Plus provides a library of models that can be used to develop an overall gasifier model that handles solids. So steady-state design and optimization studies of processes with gasifiers can be undertaken. This paper presents a simple approximate method for achieving the objective of having a gasifier model that can be exported into Aspen Dynamics. The basic idea is to use a high molecular weight hydrocarbon that is present in the Aspen library as a pseudofuel. This component should have the same 1:1 hydrogen-to-carbon ratio that is found in coal and biomass. For many plantwide dynamic studies, a rigorous high-fidelity dynamic model of the gasifier is not needed because its dynamics are very fast and the gasifier gas volume is a relatively small fraction of the total volume of the entire plant. The proposed approximate model captures the essential macroscale thermal, flow, composition, and pressure dynamics. This paper does not attempt to optimize the design or control of gasifiers but merely presents an idea of how to dynamically simulate coal gasification in an approximate way.

  5. Python Optimization Modeling Objects (Pyomo)

    E-Print Network [OSTI]

    2009-12-29

    Dec 29, 2009 ... Python Repository [10]. Coopr includes a flexible framework for applying optimizers ..... for transmission across a communications channel. This includes simple .... This example network has two major compute ..... a Lockheed Martin Company, for the United States Department of Energy's National. Nuclear ...

  6. New Models Help Optimize Development of Bakken Shale Resources...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    New Models Help Optimize Development of Bakken Shale Resources New Models Help Optimize Development of Bakken Shale Resources February 7, 2012 - 12:00pm Addthis Washington, DC -...

  7. Modeling and Optimization of Hybrid Solar Thermoelectric Systems...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Modeling and Optimization of Hybrid Solar Thermoelectric Systems with Thermosyphons Citation Details In-Document Search Title: Modeling and Optimization of Hybrid...

  8. Reactor Modeling and Recipe Optimization of Polyether Polyol Processes

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    Reactor Modeling and Recipe Optimization of Polyether Polyol Processes Spring 2013 EWO Meeting Yisu.M. Wassick. Reactor Modeling and Recipe Optimization of Polyether Polyol Processes: Polypropylene Glycol

  9. Applying the Battery Ownership Model in Pursuit of Optimal Battery...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Applying the Battery Ownership Model in Pursuit of Optimal Battery Use Strategies Applying the Battery Ownership Model in Pursuit of Optimal Battery Use Strategies 2012 DOE...

  10. Optimization of flagellar swimming by a model sperm

    E-Print Network [OSTI]

    B. U. Felderhof

    2015-05-05

    The swimming of a bead-spring chain in a viscous incompressible fluid as a model of a sperm is studied in the framework of low Reynolds number hydrodynamics. The optimal mode in the class of planar flagellar strokes of small amplitude is determined on the basis of a generalized eigenvalue problem involving two matrices which can be evaluated from the mobility matrix of the set of spheres constituting the chain. For an elastic chain with a cargo constraint for its spherical head, the actuating forces yielding a nearly optimal stroke can be determined. These can be used in a Stokesian dynamics simulation of large amplitude swimming.

  11. Tax policy can change the production path: A model of optimal oil extraction in Alaska

    E-Print Network [OSTI]

    Lin, C.-Y. Cynthia

    1 Tax policy can change the production path: A model of optimal oil extraction in Alaska Wayne@primal.ucdavis.edu * Corresponding author ABSTRACT We model the economically optimal dynamic oil production decisions for seven and an estimated inverse production function, which incorporates engineering aspects of oil production into our

  12. Optimization of neuron models using grid computing

    E-Print Network [OSTI]

    Vella, Mike

    2011-09-09

    stream_source_info Mike_Vella.ppt.txt stream_content_type text/plain stream_size 2634 Content-Encoding UTF-8 stream_name Mike_Vella.ppt.txt Content-Type text/plain; charset=UTF-8 Optimization of neuron models using grid computing... channels Set of information to be included in a model is large Single neuron multi-compartment models Why optimize? Single neuron models provide a basis for understanding cell and local circuit function Maximal conductances, compartment capacitances...

  13. Optimal thermalization in a shell model of homogeneous turbulence

    E-Print Network [OSTI]

    Thalabard, Simon

    2015-01-01

    We investigate the turbulence-induced dissipation of the large scales in a statistically homogeneous flow using an "optimal closure," which one of us (BT) has recently exposed in the context of Hamiltonian dynamics. This statistical closure employs a Gaussian model for the turbulent scales, with corresponding vanishing third cumulant, and yet it captures an intrinsic damping. The key to this apparent paradox lies in a clear distinction between true ensemble averages and their proxies, most easily grasped when one works directly with the Liouville equation rather than the cumulant hierarchy. We focus on a simple problem for which the optimal closure can be fully and exactly worked out: the relaxation arbitrarily far-from-equilibrium of a single energy shell towards Gibbs equilibrium in an inviscid shell model of 3D turbulence. The predictions of the optimal closure are validated against DNS and contrasted with those derived from EDQNM closure.

  14. Optimal PMU Placement Evaluation for Power System Dynamic State Estimation

    E-Print Network [OSTI]

    Pollefeys, Marc

    Optimal PMU Placement Evaluation for Power System Dynamic State Estimation Jinghe Zhang, Student--The synchronized phasor measurement unit (PMU), developed in the 1980s, is considered to be one of the most important devices in the future of power systems. The recent development of PMU technology provides high

  15. Optimization of hybrid dynamic/steady-state processes using process integration 

    E-Print Network [OSTI]

    Grooms, Daniel Douglas

    2009-06-02

    PROBLEM STATEMENT................................................................ 5 III OPTIMAL SYNTHESIS AND SCHEDULING OF HYBRID DYNAMIC/STEADY-STATE MASS EXCHANGE NETWORKS..................................................................................... 23 IV OPTIMAL SYNTHESIS AND SCHEDULING OF HYBRID DYNAMIC/STEADY-STATE PROPERTY INTEGRATION NETWORKS ......................................................... 24 4.1 Introduction...

  16. New methods for estimation, modeling and validation of dynamical systems using automatic differentiation 

    E-Print Network [OSTI]

    Griffith, Daniel Todd

    2005-02-17

    The main objective of this work is to demonstrate some new computational methods for estimation, optimization and modeling of dynamical systems that use automatic differentiation. Particular focus will be upon dynamical ...

  17. Optimized delta expansion for relativistic nuclear models

    E-Print Network [OSTI]

    G. Krein; R. S. Marques de Carvalho; D. P. Menezes; M. Nielsen; M. B. Pinto

    1997-09-24

    The optimized $\\delta$-expansion is a nonperturbative approach for field theoretic models which combines the techniques of perturbation theory and the variational principle. This technique is discussed in the $\\lambda \\phi^4$ model and then implemented in the Walecka model for the equation of state of nuclear matter. The results obtained with the $\\delta$ expansion are compared with those obtained with the traditional mean field, relativistic Hartree and Hartree-Fock approximations.

  18. Model-Based Transient Calibration Optimization for Next Generation...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Based Transient Calibration Optimization for Next Generation Diesel Engines Model-Based Transient Calibration Optimization for Next Generation Diesel Engines 2005 Diesel Engine...

  19. Dynamic Response Optimization of Complex Multibody Systems in a Penalty Formulation using Adjoint Sensitivity

    E-Print Network [OSTI]

    Yitao Zhu; Daniel Dopico; Corina Sandu; Adrian Sandu

    2014-10-30

    Multibody dynamics simulations are currently widely accepted as valuable means for dynamic performance analysis of mechanical systems. The evolution of theoretical and computational aspects of the multibody dynamics discipline make it conducive these days for other types of applications, in addition to pure simulations. One very important such application is design optimization. A very important first step towards design optimization is sensitivity analysis of multibody system dynamics. Dynamic sensitivities are often calculated by means of finite differences. Depending of the number of parameters involved, this procedure can be computationally expensive. Moreover, in many cases, the results suffer from low accuracy when real perturbations are used. The main contribution to the state-of-the-art brought by this study is the development of the adjoint sensitivity approach of multibody systems in the context of the penalty formulation. The theory developed is demonstrated on one academic case study, a five-bar mechanism, and on one real-life system, a 14-DOF vehicle model. The five-bar mechanism is used to illustrate the sensitivity approach derived in this paper. The full vehicle model is used to demonstrate the capability of the new approach developed to perform sensitivity analysis and gradient-based optimization for large and complex multibody systems with respect to multiple design parameters.

  20. Optimal Model-Based Production Planning

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    Given Refinery configuration: Process units Feedstock & Final Product Objective Select crude oils Hydrotreatment Gasoline blending Distillate blending Gas oil blending Cat Crack CDU crude1 crude2 butane Fuel gas1 Optimal Model-Based Production Planning for Refinery Operation Abdulrahman Alattas Advisor

  1. Optimal Model-Based Production Planning for

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    Motivation Refining Operation and crude cost variable cost of production Largest product price components Key to refinery profit and economics Refinery production planning models Operation optimization Crude selection Statement Cat Ref Hydrotreatment Gasoline blending Distillate blending Gas oil blending Cat Crack CDU crude1

  2. Optimal Model-Based Production Planning

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    Given Refinery configuration: Process units Feedstock & Final Product Objective Select crude oils;2 Introduction Refinery production planning models Operation optimization Crude selection Maximizing profit Hydrotreatment Gasoline blending Distillate blending Gas oil blending Cat Crack CDU crude1 crude2 butane Fuel gas

  3. Optimal Passive Dynamics for Torque/Force Control Kevin Kemper, Devin Koepl and Jonathan Hurst

    E-Print Network [OSTI]

    Hurst, Jonathan

    Optimal Passive Dynamics for Torque/Force Control Kevin Kemper, Devin Koepl and Jonathan Hurst software control strategy. Discussions about the passive dynamics are often imprecise, lacking's passive dynamics (stiffness, damping, motor inertia and torque limits) and the resulting performance

  4. Dynamic models for nonstationary signal segmentation

    E-Print Network [OSTI]

    Penny, Will

    Dynamic models for nonstationary signal segmentation William D. Penny and Stephen J. Roberts w.penny

  5. Development of a Laboratory Verified Single-Duct VAV System Model with Fan Powered Terminal Units Optimized Using Computational Fluid Dynamics 

    E-Print Network [OSTI]

    Davis, Michael A.

    2011-10-21

    Single Duct Variable Air Volume (SDVAV) systems use series and parallel Fan Powered Terminal Units to control the air flow in conditioned spaces. This research developed a laboratory verified model of SDVAV systems that ...

  6. Mathematical Modeling for CostMathematical Modeling for Cost Optimization of PV RecyclingOptimization of PV Recycling

    E-Print Network [OSTI]

    Bergman, Keren

    Mathematical Modeling for CostMathematical Modeling for Cost Optimization of PV Recycling of plants Capital costs to open up a recycling center 4 #12;Time Horizon for PV Recycling Infrastructure 5 cost $189K System optimal cost $1079K 11 #12;PV Recycling ­Cost Optimization 1. Where is the optimized

  7. DYNAMIC MODELING FUEL PROCESSORS

    E-Print Network [OSTI]

    Mease, Kenneth D.

    turbine module (compressor and turbine sub-modules) Catalytic oxidizer Combustor module Heat exchanger, PEM, Gas Turbine General Model Assumptions · 1D process flow · Well-stirred within nodal volume · Slow reactants #12;Steam Reformation ­ Occurs in Reformer and Fuel Cells Methane reformation reaction Water Gas

  8. MODELING, VERIFICATION AND OPTIMIZATION OF HYBRID GROUND SOURCE HEAT PUMP

    E-Print Network [OSTI]

    MODELING, VERIFICATION AND OPTIMIZATION OF HYBRID GROUND SOURCE HEAT PUMP SYSTEMS IN ENERGYPLUS, VERIFICATION AND OPTIMIZATION OF HYBRID GROUND SOURCE HEAT PUMP SYSTEMS IN ENERGYPLUS Thesis Approved by: Dr.................................................................................................................... 16 MODELING OF HYBRID GROUND SOURCE HEAT PUMP SYSTEMS IN ENERGYPLUS

  9. Modeling Blog Dynamics Michaela Gotz

    E-Print Network [OSTI]

    Leskovec, Jure

    Modeling Blog Dynamics Michaela G¨otz Cornell University goetz@cs.cornell.edu Jure Leskovec@cs.cmu.edu Christos Faloutsos Carnegie Mellon University christos@cs.cmu.edu Abstract How do blogs produce posts? What local, underlying mech- anisms lead to the bursty temporal behaviors observed in blog networks? Earlier

  10. Provably near-optimal algorithms for multi-stage stochastic optimization models in operations management

    E-Print Network [OSTI]

    Shi, Cong, Ph.D. Massachusetts Institute of Technology

    2012-01-01

    Many if not most of the core problems studied in operations management fall into the category of multi-stage stochastic optimization models, whereby one considers multiple, often correlated decisions to optimize a particular ...

  11. optimal initial conditions for coupling ice sheet models to earth...

    Office of Scientific and Technical Information (OSTI)

    optimal initial conditions for coupling ice sheet models to earth system models Perego, Mauro Sandia National Laboratories Sandia National Laboratories; Price, Stephen F. Dr...

  12. Finding Benefits by Modeling and Optimizing Steam and Power Systems 

    E-Print Network [OSTI]

    Jones, B.; Nelson, D.

    2007-01-01

    A site-wide steam modeling and optimization program (Visual MESA) was implemented at the INEOS Chocolate Bayou site. This program optimizes steam production, compressor turbine extraction, pump operation (turbine/motor) operation, as well...

  13. 15.094 Systems Optimization: Models and Computation, Spring 2002

    E-Print Network [OSTI]

    Freund, Robert Michael

    A computational and application-oriented introduction to the modeling of large-scale systems in a wide variety of decision-making domains and the optimization of such systems using state-of-the-art optimization software. ...

  14. Optimization Modelling Example Design Implementation Conclusions A Structure-Conveying Modelling Language for

    E-Print Network [OSTI]

    Grothey, Andreas

    Optimization Modelling Example Design Implementation Conclusions A Structure-Conveying Modelling Languages for Mathematical Programming 3 An example problem from network design 4 Design of Structured, K. Woodsend Structure-Conveying Modelling Language #12;Optimization Modelling Example Design

  15. Improved Crosstalk Modeling with Applications to Noise Constrained Interconnect Optimization

    E-Print Network [OSTI]

    Pan, David Z.

    Improved Crosstalk Modeling with Applications to Noise Constrained Interconnect Optimization This paper presents a highly accurate yet efficient crosstalk noise model, the 2-¢ model, and applies to be noise immune, ac- curate yet efficient noise models are needed to guide interconnect optimizations

  16. Dynamic online optimization of a house heating system in a fluctuating energy price

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Dynamic online optimization of a house heating system in a fluctuating energy price scenario in this problem is the time- varying nature of the main disturbances, which are the energy price and outdoor that there is a great economical gain in using dynamic optimization for the case of variable energy price. 1

  17. A Remarkable Property of the Dynamic Optimization Extremals?

    E-Print Network [OSTI]

    Delfim Fernando Marado Torres

    1910-10-81

    the new relation, methods for obtaining conserved quantities along the ... the 4th International Optimization Conference in Portugal, Optimization 2001, Aveiro,.

  18. Dynamic Modeling and Wavelet-Based Multi-Parametric Tuning and Validation for HVAC Systems 

    E-Print Network [OSTI]

    Liang, Shuangshuang

    2014-07-10

    Dynamic Heating, Ventilation, and Air-Conditioning (HVAC) system models are used for the purpose of control design, fault detection and diagnosis, system analysis, design and optimization. Therefore, ensuring the accuracy ...

  19. A Relativistic Dynamical Collapse Model

    E-Print Network [OSTI]

    Philip Pearle

    2014-12-21

    A model is discussed where all operators are constructed from a quantum scalar field whose energy spectrum takes on all real values. The Schr\\"odinger picture wave function depends upon space and time coordinates for each particle, as well as an inexorably increasing evolution parameter $s$ which labels a foliation of space-like hypersurfaces. The model is constructed to be manifestly Lorentz invariant in the interaction picture. Free particle states and interactions are discussed in this framework. Then, the formalism of the CSL (Continuous Spontaneous Localization) theory of dynamical collapse is applied. The collapse-generating operator is chosen to to be the particle number space-time density. Unlike previous relativistically invariant models, the vacuum state is not excited. The collapse dynamics depends upon two parameters, a parameter $\\Lambda$ which represents the collapse rate/volume and a scale factor $\\ell$. A common example of collapse dynamics, involving a clump of matter in a superposition of two locations, is analyzed. The collapse rate is shown to be identical to that of non-relativistic CSL when the GRW-CSL choice of $\\ell=a=10^{-5}$cm, is made, along with $\\Lambda=\\lambda/a^{3}$ (GRW-CSL choice $\\lambda=10^{-16}s^{-1}$). However, it is also shown that the change of mass of a nucleon over the age of the universe is then unacceptably large. The case where $\\ell$ is the size of the universe is then considered. It is shown that the collapse behavior is satisfactory and the change of mass over the age of the universe is acceptably small, when $\\Lambda= \\lambda/\\ell a^{2}$.

  20. Error Control Based Model Reduction for Parameter Optimization of Elliptic

    E-Print Network [OSTI]

    of technical devices that rely on multiscale processes, such as fuel cells or batteries. As the solutionError Control Based Model Reduction for Parameter Optimization of Elliptic Homogenization Problems optimization of elliptic multiscale problems with macroscopic optimization functionals and microscopic material

  1. Computational Modeling and Optimization of Proton Exchange Membrane Fuel Cells

    E-Print Network [OSTI]

    Victoria, University of

    Computational Modeling and Optimization of Proton Exchange Membrane Fuel Cells by Marc Secanell and Optimization of Proton Exchange Membrane Fuel Cells by Marc Secanell Gallart Bachelor in Engineering cells. In this thesis, a computational framework for fuel cell analysis and optimization is presented

  2. Model Identification for Optimal Diesel Emissions Control

    SciTech Connect (OSTI)

    Stevens, Andrew J.; Sun, Yannan; Song, Xiaobo; Parker, Gordon

    2013-06-20

    In this paper we develop a model based con- troller for diesel emission reduction using system identification methods. Specifically, our method minimizes the downstream readings from a production NOx sensor while injecting a minimal amount of urea upstream. Based on the linear quadratic estimator we derive the closed form solution to a cost function that accounts for the case some of the system inputs are not controllable. Our cost function can also be tuned to trade-off between input usage and output optimization. Our approach performs better than a production controller in simulation. Our NOx conversion efficiency was 92.7% while the production controller achieved 92.4%. For NH3 conversion, our efficiency was 98.7% compared to 88.5% for the production controller.

  3. Modeling and Multidimensional Optimization of a Tapered Free...

    Office of Scientific and Technical Information (OSTI)

    Electron Laser Citation Details In-Document Search Title: Modeling and Multidimensional Optimization of a Tapered Free Electron Laser Authors: Jiao, Y. ; SLAC Beijing, Inst....

  4. Dynamical modeling of tidal streams

    SciTech Connect (OSTI)

    Bovy, Jo, E-mail: bovy@ias.edu [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States)

    2014-11-01

    I present a new framework for modeling the dynamics of tidal streams. The framework consists of simple models for the initial action-angle distribution of tidal debris, which can be straightforwardly evolved forward in time. Taking advantage of the essentially one-dimensional nature of tidal streams, the transformation to position-velocity coordinates can be linearized and interpolated near a small number of points along the stream, thus allowing for efficient computations of a stream's properties in observable quantities. I illustrate how to calculate the stream's average location (its 'track') in different coordinate systems, how to quickly estimate the dispersion around its track, and how to draw mock stream data. As a generative model, this framework allows one to compute the full probability distribution function and marginalize over or condition it on certain phase-space dimensions as well as convolve it with observational uncertainties. This will be instrumental in proper data analysis of stream data. In addition to providing a computationally efficient practical tool for modeling the dynamics of tidal streams, the action-angle nature of the framework helps elucidate how the observed width of the stream relates to the velocity dispersion or mass of the progenitor, and how the progenitors of 'orphan' streams could be located. The practical usefulness of the proposed framework crucially depends on the ability to calculate action-angle variables for any orbit in any gravitational potential. A novel method for calculating actions, frequencies, and angles in any static potential using a single orbit integration is described in the Appendix.

  5. MEAN-RISK OPTIMIZATION MODELS FOR ELECTRICITY PORTFOLIO MANAGEMENT 1 Mean-risk optimization models for electricity

    E-Print Network [OSTI]

    Römisch, Werner

    the model via uncertain electricity demand, heat demand, spot prices, and future prices. The objectiveMEAN-RISK OPTIMIZATION MODELS FOR ELECTRICITY PORTFOLIO MANAGEMENT 1 Mean-risk optimization models for electricity portfolio management Andreas Eichhorn and Werner R¨omisch Abstract-- The possibility

  6. Photocathode Optimization for a Dynamic Transmission Electron Microscope: Final Report

    SciTech Connect (OSTI)

    Ellis, P; Flom, Z; Heinselman, K; Nguyen, T; Tung, S; Haskell, R; Reed, B W; LaGrange, T

    2011-08-04

    The Dynamic Transmission Electron Microscope (DTEM) team at Harvey Mudd College has been sponsored by LLNL to design and build a test setup for optimizing the performance of the DTEM's electron source. Unlike a traditional TEM, the DTEM achieves much faster exposure times by using photoemission from a photocathode to produce electrons for imaging. The DTEM team's work is motivated by the need to improve the coherence and current density of the electron cloud produced by the electron gun in order to increase the image resolution and contrast achievable by DTEM. The photoemission test setup is nearly complete and the team will soon complete baseline tests of electron gun performance. The photoemission laser and high voltage power supply have been repaired; the optics path for relaying the laser to the photocathode has been finalized, assembled, and aligned; the internal setup of the vacuum chamber has been finalized and mostly implemented; and system control, synchronization, and data acquisition has been implemented in LabVIEW. Immediate future work includes determining a consistent alignment procedure to place the laser waist on the photocathode, and taking baseline performance measurements of the tantalum photocathode. Future research will examine the performance of the electron gun as a function of the photoemission laser profile, the photocathode material, and the geometry and voltages of the accelerating and focusing components in the electron gun. This report presents the team's progress and outlines the work that remains.

  7. Modelling and Dynamic Simulation for Process Control

    E-Print Network [OSTI]

    Skogestad, Sigurd

    principles for model development are outlined, and these principles are applied to a simple ash tank (which. In this paper we consider dynamic process models obtained using fundamental principles (eg. based reactor, a simple trend analysis using temperature measurements may be suÆcient. Dynamic models

  8. Sensitivity of Optimal Operation of an Activated Sludge Process Model

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Sensitivity of Optimal Operation of an Activated Sludge Process Model Antonio Araujo, Simone sensitivity analysis of optimal operation conducted on an activated sludge process model based on the test.[7] applied a systematic procedure for control structure design of an activated sludge process

  9. Local energy management through mathematical modeling and optimization

    E-Print Network [OSTI]

    Craft David (David Loren), 1973-

    2004-01-01

    (cont.) Extensions to the core TOTEM model include a demand charge model, used for making daily optimal control decisions when the electric bill includes a charge based on the monthly maximum power draw. The problem of ...

  10. Utility system integration and optimization models for nuclear power management

    E-Print Network [OSTI]

    Deaton, Paul Ferris

    1973-01-01

    A nuclear power management model suitable for nuclear utility systems optimization has been developed for use in multi-reactor fuel management planning over periods of up to ten years. The overall utility planning model ...

  11. Quantitative Modeling of High Temperature Magnetization Dynamics

    SciTech Connect (OSTI)

    Zhang, Shufeng

    2009-03-01

    Final Technical Report Project title: Quantitative Modeling of High Temperature Magnetization Dynamics DOE/Office of Science Program Manager Contact: Dr. James Davenport

  12. Spectral Collocation-based Optimization in Parameter Estimation for Nonlinear Time-Varying Dynamical Systems

    E-Print Network [OSTI]

    Deshmukh, Venkatesh

    Dynamical Systems Venkatesh Deshmukh Center for Nonlinear Dynamics and Control Department of Mechanical dynamic system models to be constructed from available data. The parameters to be estimated are assumed in the dynamic system models are assumed to have a known form, and the models are assumed to be parameter affine

  13. Dynamic competition model for construction contractors 

    E-Print Network [OSTI]

    Kim, Hyung Jin

    2004-01-01

    as an entity in a dynamic system, in which every entity is a profit optimizer responding to market conditions as well as its competitors' actions. In construction, the issue of competition has been focused on competitive bidding, which is a critical mechanism...

  14. Optimization of a Two-Fluid Hydrodynamic Model of Churn-Turbulent Flow

    SciTech Connect (OSTI)

    Donna Post Guillen

    2009-07-01

    A hydrodynamic model of two-phase, churn-turbulent flows is being developed using the computational multiphase fluid dynamics (CMFD) code, NPHASE-CMFD. The numerical solutions obtained by this model are compared with experimental data obtained at the TOPFLOW facility of the Institute of Safety Research at the Forschungszentrum Dresden-Rossendorf. The TOPFLOW data is a high quality experimental database of upward, co-current air-water flows in a vertical pipe suitable for validation of computational fluid dynamics (CFD) codes. A five-field CMFD model was developed for the continuous liquid phase and four bubble size groups using mechanistic closure models for the ensemble-averaged Navier-Stokes equations. Mechanistic models for the drag and non-drag interfacial forces are implemented to include the governing physics to describe the hydrodynamic forces controlling the gas distribution. The closure models provide the functional form of the interfacial forces, with user defined coefficients to adjust the force magnitude. An optimization strategy was devised for these coefficients using commercial design optimization software. This paper demonstrates an approach to optimizing CMFD model parameters using a design optimization approach. Computed radial void fraction profiles predicted by the NPHASE-CMFD code are compared to experimental data for four bubble size groups.

  15. Conceptual aircraft dynamics from inverse aircraft modeling 

    E-Print Network [OSTI]

    Ziegler, Gregory E

    1999-01-01

    This thesis presents a method of construe' ting a nonlinear dynamics model of a theoretical aircraft from the nonlinear batch simulation of an existing aircrew This method provides control law designers with a method of fabricating nonlinear models...

  16. Dynamical Arrest, Structural Disorder, and Optimization of Organic Photovoltaic Devices

    SciTech Connect (OSTI)

    Gould, Ian; Dmitry, Matyushov

    2014-09-11

    This project describes fundamental experimental and theoretical work that relates to charge separation and migration in the solid, heterogeneous or aggregated state. Marcus theory assumes a system in equilibrium with all possible solvent (dipolar) configurations, with rapid interconversion among these on the ET timescale. This project has addressed the more general situation where the medium is at least partially frozen on the ET timescale, i.e. under conditions of dynamical arrest. The approach combined theory and experiment and includes: (1) Computer simulations of model systems, (2) Development of analytical procedures consistent with computer experiment and (3) Experimental studies and testing of the formal theories on this data. Electron transfer processes are unique as a consequence of the close connection between kinetics, spectroscopy and theory, which is an essential component of this work.

  17. Assessing FPAR Source and Parameter Optimization Scheme in Application of a Diagnostic Carbon Flux Model

    SciTech Connect (OSTI)

    Turner, D P; Ritts, W D; Wharton, S; Thomas, C; Monson, R; Black, T A

    2009-02-26

    The combination of satellite remote sensing and carbon cycle models provides an opportunity for regional to global scale monitoring of terrestrial gross primary production, ecosystem respiration, and net ecosystem production. FPAR (the fraction of photosynthetically active radiation absorbed by the plant canopy) is a critical input to diagnostic models, however little is known about the relative effectiveness of FPAR products from different satellite sensors nor about the sensitivity of flux estimates to different parameterization approaches. In this study, we used multiyear observations of carbon flux at four eddy covariance flux tower sites within the conifer biome to evaluate these factors. FPAR products from the MODIS and SeaWiFS sensors, and the effects of single site vs. cross-site parameter optimization were tested with the CFLUX model. The SeaWiFs FPAR product showed greater dynamic range across sites and resulted in slightly reduced flux estimation errors relative to the MODIS product when using cross-site optimization. With site-specific parameter optimization, the flux model was effective in capturing seasonal and interannual variation in the carbon fluxes at these sites. The cross-site prediction errors were lower when using parameters from a cross-site optimization compared to parameter sets from optimization at single sites. These results support the practice of multisite optimization within a biome for parameterization of diagnostic carbon flux models.

  18. Polymer Reaction Engineering Laboratory -University of Maryland at College Park Reactor Dynamics, Control, Optimization

    E-Print Network [OSTI]

    Rubloff, Gary W.

    , Control, Optimization Exothermic polymerization reactions in continuous flow reactors may cause complex control policies for semibatch free radical copolymerization processes (K.Y. Choi), J. Appl. Polym. Sci. An experimental study of multiobjective dynamic optimization of a semibatch copolymerization process (K.Y. Choi

  19. Dynamic online optimization of a house heating system in a fluctuating energy price

    E-Print Network [OSTI]

    Skogestad, Sigurd

    energy price. 1. INTRODUCTION Recently, great attention has been given to renewable gen- eration sources building heating system optimization where the goal is the minimization of energy costs, which in turn the energy cost. In this scheme, a dynamic optimization problem is solved at each sample time with new states

  20. MIP Models and BB Strategies in Brachytherapy Treatment Optimization

    E-Print Network [OSTI]

    Meyer, Robert R.

    MIP Models and BB Strategies in Brachytherapy Treatment Optimization Robert R. Meyer (rrm­Madison Abstract. Brachytherapy (brachy being derived from a Greek word meaning short) is the treatment of cancer: brachytherapy, prostate cancer, branch­and­bound, optimization, inte­ ger programming, treatment planning

  1. Modeling and Optimal Design of Di ractive Optical Structures

    E-Print Network [OSTI]

    Dobson, David C.

    Modeling and Optimal Design of Di ractive Optical Structures Gang Bao Department of Mathematics be designed to perform functions unattainable with traditionaloptical elements. For example, structures and for the determination of optimal" device designs. In contrast to the case of traditional optical structures, geometrical

  2. DYNAMIC EMBEDDED OPTIMIZATION AND SHOOTING METHODS FOR POWER

    E-Print Network [OSTI]

    for Deregulated Electric Power Systems: Optimization, Control, and Computational Intelligence, J. Chow, F. Wu are not always established formally, nevertheless underlying optimization principles apply. Design questions is usually undesirable, and tends to be induced by inter- actions between generator controllers. In many

  3. A Dynamic Near-Optimal Algorithm for Online Linear Programming

    E-Print Network [OSTI]

    Ye, Yinyu

    -time forward dynamic pricing for PEVs charging/discharging on smart-grid; Yinyu Ye Online Linear Program 2009

  4. Optimization of the dynamic behavior of strongly nonlinear heterogeneous materials

    E-Print Network [OSTI]

    Herbold, Eric B.

    2008-01-01

    J. (2000) Response to Thermites to Dynamic High Pressure andmechanical deformation as in thermites Walley et al. (2000).

  5. Online Modeling in the Process Industry for Energy Optimization 

    E-Print Network [OSTI]

    Alexander, J.

    1988-01-01

    "This paper discusses how steady state models are being used in the process industry to perform online energy optimization of steam and electrical systems. It presents process demands commonly found in the processing industry in terms of steam...

  6. An Optimization Model for Eco-Driving at Signalized Intersection 

    E-Print Network [OSTI]

    Chen, Zhi

    2013-07-15

    This research develops an optimization model for eco-driving at signalized intersection. In urban areas, signalized intersections are the “hot spots” of air emissions and have significant negative environmental and health impacts. Eco-driving is a...

  7. Simulation Models to Optimize the Energy Consumption of Buildings 

    E-Print Network [OSTI]

    Burhenne, S.; Jacob, D.

    2008-01-01

    In practice, building operation systems are only adjusted during commissioning. This is done manually and leads to failure-free but often inefficient operation. This work deals with the development of simulation models to describe and optimize...

  8. Optimizing MLC-based STT-RAM Caches by Dynamic Block Size Reconfiguration

    E-Print Network [OSTI]

    Wong, Weng Fai

    Optimizing MLC-based STT-RAM Caches by Dynamic Block Size Reconfiguration Jianxing Wang, Pooja Roy that MLC STT-RAM can achieve 2× the storage density of SLC and thus improves system performance. In this paper, we propose an architectural design to dynamically reconfigure the cache block size for a MLC STT

  9. Gain-scheduled `1 -optimal control for boiler-turbine dynamics

    E-Print Network [OSTI]

    Shamma, Jeff S.

    Gain-scheduled `1 -optimal control for boiler-turbine dynamics with actuator saturation Pang; accepted 2 June 2003 Abstract This paper presents a gain-scheduled approach for boiler-turbine controller the magnitude and rate saturation constraints on actuators. The nonlinear boiler-turbine dynamics is brought

  10. Optimal dynamical range of excitable networks at criticality

    E-Print Network [OSTI]

    Loss, Daniel

    is that optimal information processing is to be found near phase transitions. However, this heuristic hypothesis and retinal ganglionar cell output. Synchronization and global oscillations also emerge from the network

  11. Dynamics Modelling of Biolistic Gene Guns

    SciTech Connect (OSTI)

    Zhang, M.; Tao, W.; Pianetta, P.A.

    2009-06-04

    The gene transfer process using biolistic gene guns is a highly dynamic process. To achieve good performance, the process needs to be well understood and controlled. Unfortunately, no dynamic model is available in the open literature for analysing and controlling the process. This paper proposes such a model. Relationships of the penetration depth with the helium pressure, the penetration depth with the acceleration distance, and the penetration depth with the micro-carrier radius are presented. Simulations have also been conducted. The results agree well with experimental results in the open literature. The contribution of this paper includes a dynamic model for improving and manipulating performance of the biolistic gene gun.

  12. Contingency contractor optimization. phase 3, model description and formulation.

    SciTech Connect (OSTI)

    Gearhart, Jared Lee; Adair, Kristin Lynn; Jones, Katherine A.; Bandlow, Alisa; Detry, Richard Joseph; Durfee, Justin D.; Jones, Dean A.; Martin, Nathaniel; Nanco, Alan Stewart; Nozick, Linda Karen

    2013-06-01

    The goal of Phase 3 the OSD ATL Contingency Contractor Optimization (CCO) project is to create an engineering prototype of a tool for the contingency contractor element of total force planning during the Support for Strategic Analysis (SSA). An optimization model was developed to determine the optimal mix of military, Department of Defense (DoD) civilians, and contractors that accomplishes a set of user defined mission requirements at the lowest possible cost while honoring resource limitations and manpower use rules. An additional feature allows the model to understand the variability of the Total Force Mix when there is uncertainty in mission requirements.

  13. Contingency contractor optimization. Phase 3, model description and formulation.

    SciTech Connect (OSTI)

    Gearhart, Jared Lee; Adair, Kristin Lynn; Jones, Katherine A.; Bandlow, Alisa; Durfee, Justin D.; Jones, Dean A.; Martin, Nathaniel; Detry, Richard Joseph; Nanco, Alan Stewart; Nozick, Linda Karen [Cornell University

    2013-10-01

    The goal of Phase 3 the OSD ATL Contingency Contractor Optimization (CCO) project is to create an engineering prototype of a tool for the contingency contractor element of total force planning during the Support for Strategic Analysis (SSA). An optimization model was developed to determine the optimal mix of military, Department of Defense (DoD) civilians, and contractors that accomplishes a set of user defined mission requirements at the lowest possible cost while honoring resource limitations and manpower use rules. An additional feature allows the model to understand the variability of the Total Force Mix when there is uncertainty in mission requirements.

  14. Efficient Production Optimization Using Flow Network Models 

    E-Print Network [OSTI]

    Lerlertpakdee, Pongsathorn

    2012-10-19

    to predict the response of real reservoirs under proposed changes in the model inputs. To speed up reservoir response predictions without compromising accuracy, fast surrogate models have been proposed. These models are either derived by preserving...

  15. Optimizing Blast Furnace Operation to Increase Efficiency and...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Optimizing Blast Furnace Operation to Increase Efficiency and Lower Costs State-of-the-Art Computational Fluid Dynamics Model Optimizes Fuel Rate in Blast Furnaces The blast...

  16. Modeling of Alpine Atmospheric Dynamics II

    E-Print Network [OSTI]

    Gohm, Alexander

    Modeling of Alpine Atmospheric Dynamics II 707.424, VU 2, SS2005 Unit 7: Model code structure: mesoscale convective system 17-18 April 2004: Sierra hydraulic jump case 21 January 2005: the "Universiade) Introduction (brief description of the phenomenon and a description of the model and of the measurements

  17. Dynamic modeling issues for power system applications 

    E-Print Network [OSTI]

    Song, Xuefeng

    2005-02-17

    Power system dynamics are commonly modeled by parameter dependent nonlinear differential-algebraic equations (DAE) x ???p y x f ) and 0 = p y x g ) . Due to (,, (,, the algebraic constraints, we cannot directly perform...

  18. Gas permeation carbon capture --- Process modeling and optimization

    SciTech Connect (OSTI)

    Morinelly, Juan; Miller, David

    2011-01-01

    A multi-staged gas permeation carbon capture process model was developed in Aspen Custom Modeler{reg_sign} (ACM) and optimized in the context of the retrofit of a 550 MW subcritical pulverized coal (PC) power plant. The gas permeation stages in the process are described by a custom multi-component, hollowfiber membrane model. Gas transport across the asymmetric membrane was modeled according to the solution-diffusion model for the selective skin layer and the assumption of negligible flux resistance by the porous support. Counter-current, one-dimensional plug flow was assumed with permeate pressure drop in the fiber lumen side due to capillary constrained flow. A modular optimization framework was used to minimize the levelized cost of electricity (LCOE) by optimizing a set of key process variables. The framework allows the external control of multiple simulation modules from different software packages from a common interface.

  19. Keratin Dynamics: Modeling the Interplay between Turnover and Transport

    E-Print Network [OSTI]

    Stephanie Portet; Anotida Madzvamuse; Andy Chung; Rudolf E. Leube; Reinhard Windoffer

    2015-04-01

    Keratin are among the most abundant proteins in epithelial cells. Functions of the keratin network in cells are shaped by their dynamical organization. Using a collection of experimentally-driven mathematical models, different hypotheses for the turnover and transport of the keratin material in epithelial cells are tested. The interplay between turnover and transport and their effects on the keratin organization in cells are hence investigated by combining mathematical modeling and experimental data. Amongst the collection of mathematical models considered, a best model strongly supported by experimental data is identified. Fundamental to this approach is the fact that optimal parameter values associated with the best fit for each model are established. The best candidate among the best fits is characterized by the disassembly of the assembled keratin material in the perinuclear region and an active transport of the assembled keratin. Our study shows that an active transport of the assembled keratin is required to explain the experimentally observed keratin organization.

  20. Modeling and Optimization of PEMFC Systems and its Application to Direct Hydrogen Fuel Cell Vehicles

    E-Print Network [OSTI]

    Zhao, Hengbing; Burke, Andy

    2008-01-01

    In the original fuel cell optimization model [11], only theIn the original fuel cell optimization model, only the dryof the fuel cell system and optimization of the operating

  1. Protein viscoelastic dynamics: a model system

    E-Print Network [OSTI]

    Craig Fogle; Joseph Rudnick; David Jasnow

    2015-02-02

    A model system inspired by recent experiments on the dynamics of a folded protein under the influence of a sinusoidal force is investigated and found to replicate many of the response characteristics of such a system. The essence of the model is a strongly over-damped oscillator described by a harmonic restoring force for small displacements that reversibly yields to stress under sufficiently large displacement. This simple dynamical system also reveals unexpectedly rich behavior, exhibiting a series of dynamical transitions and analogies with equilibrium thermodynamic phase transitions. The effects of noise and of inertia are briefly considered and described.

  2. A next-generation modeling capability assesses wind turbine array fluid dynamics and aeroelastic simulations

    E-Print Network [OSTI]

    A next-generation modeling capability assesses wind turbine array fluid dynamics and aeroelastic simulations Characterizing and optimizing overall performance of wind plants composed of large numbers at the National Renewable Energy Laboratory (NREL) are coupling physical models of the atmosphere and wind

  3. Modeling and Optimizing Ergonomic Activities in Automobile Product Development

    E-Print Network [OSTI]

    da Silva, Alberto Rodrigues

    Modeling and Optimizing Ergonomic Activities in Automobile Product Development João Ferreira Anna.silva@acm.org Abstract We collect ergonomic rules and normative rules considerations for automobile business and modeled as use of past experience. Also we intend to define ergonomic associated templates, which reflect

  4. OPTIMAL EXPERIMENTAL DESIGN FOR MODELING BATTERY DEGRADATION Joel C. Forman

    E-Print Network [OSTI]

    Krstic, Miroslav

    , battery health dependence on voltage, and a lack of power fade under the cy- cling conditions. The useOPTIMAL EXPERIMENTAL DESIGN FOR MODELING BATTERY DEGRADATION Joel C. Forman Mechanical Engineering.edu ABSTRACT Accurate battery health modeling allows one to make better design decisions, enables health

  5. Reconciling the optimal and empirical approaches to modelling stomatal conductance

    E-Print Network [OSTI]

    atmospheric CO2, and thus can be used to test for stomatal acclimation to elevated CO2. The reconciliation cost of carbon gain. The new model is fitted to a range of datasets ranging from tropical to boreal models, marginal water cost of carbon, stomatal conductance, stomatal optimization Received 24 May 2010

  6. INDDGO: Integrated Network Decomposition & Dynamic programming for Graph Optimization

    SciTech Connect (OSTI)

    Groer, Christopher S; Sullivan, Blair D; Weerapurage, Dinesh P

    2012-10-01

    It is well-known that dynamic programming algorithms can utilize tree decompositions to provide a way to solve some \\emph{NP}-hard problems on graphs where the complexity is polynomial in the number of nodes and edges in the graph, but exponential in the width of the underlying tree decomposition. However, there has been relatively little computational work done to determine the practical utility of such dynamic programming algorithms. We have developed software to construct tree decompositions using various heuristics and have created a fast, memory-efficient dynamic programming implementation for solving maximum weighted independent set. We describe our software and the algorithms we have implemented, focusing on memory saving techniques for the dynamic programming. We compare the running time and memory usage of our implementation with other techniques for solving maximum weighted independent set, including a commercial integer programming solver and a semi-definite programming solver. Our results indicate that it is possible to solve some instances where the underlying decomposition has width much larger than suggested by the literature. For certain types of problems, our dynamic programming code runs several times faster than these other methods.

  7. Consistent nonlinear dynamics: identifying model inadequacy

    E-Print Network [OSTI]

    Patrick E. McSharry; Leonard A. Smith

    2004-03-09

    Empirical modelling often aims for the simplest model consistent with the data. A new technique is presented which quantifies the consistency of the model dynamics as a function of location in state space. As is well-known, traditional statistics of nonlinear models like root-mean-square (RMS) forecast error can prove misleading. Testing consistency is shown to overcome some of the deficiencies of RMS error, both within the perfect model scenario and when applied to data from several physical systems using previously published models. In particular, testing for consistent nonlinear dynamics provides insight towards (i) identifying when a delay reconstruction fails to be an embedding, (ii) allowing state dependent model selection and (iii) optimising local neighbourhood size. It also provides a more relevant (state dependent) threshold for identifying false nearest neighbours.

  8. Bayesian Nonparametric Inference of Switching Dynamic Linear Models

    E-Print Network [OSTI]

    Fox, Emily Beth

    Many complex dynamical phenomena can be effectively modeled by a system that switches among a set of conditionally linear dynamical modes. We consider two such models: the switching linear dynamical system (SLDS) and the ...

  9. Optimal Model-Based Production Planning

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    Given Refinery configuration: Process units Feedstock & Final Product Objective Select crude oils Hydrotreatment Gasoline blending Distillate blending Gas oil blending Cat Crack CDU crude1 crude2 butane Fuel gas Refinery Planning Model Swing cut models: Improvement from the fixed-yield approach Crude oil cuts

  10. Optimizing Symbolic Model Checking for Statecharts

    E-Print Network [OSTI]

    Beame, Paul

    model checking to a statecharts model, that of an electrical power distribution (EPD) system for Boeing checking based on binary decision diagrams is a powerful formal verification technique for reactive systems of a collision avoidance system and a fault- tolerant electrical power distribution (EPD) system, both used

  11. Modeling the Dynamics of Fermentation and Respiratory

    E-Print Network [OSTI]

    Sheffield, University of

    Modeling the Dynamics of Fermentation and Respiratory Processes in a Groundwater Plume of Phenolic implemented into a field- scale reactive transport model of a groundwater plume of phenolic contaminants toxicity toward degradation, bioavailability of mineral oxides, and adsorption of biogenic Fe(II) species

  12. Six Degree of Freedom Morphing Aircraft Dynamical Model with Aerodynamics 

    E-Print Network [OSTI]

    Niksch, Adam

    2010-01-14

    model of a morphing aircraft is needed. This paper develops an aerodynamic model and a dynamic model of a morphing flying wing aircraft. The dynamic model includes realistic aerodynamic forces, consisting of lift, drag, and pitching moment about...

  13. Block-oriented modeling of superstructure optimization problems

    SciTech Connect (OSTI)

    Friedman, Z; Ingalls, J; Siirola, JD; Watson, JP

    2013-10-15

    We present a novel software framework for modeling large-scale engineered systems as mathematical optimization problems. A key motivating feature in such systems is their hierarchical, highly structured topology. Existing mathematical optimization modeling environments do not facilitate the natural expression and manipulation of hierarchically structured systems. Rather, the modeler is forced to "flatten" the system description, hiding structure that may be exploited by solvers, and obfuscating the system that the modeling environment is attempting to represent. To correct this deficiency, we propose a Python-based "block-oriented" modeling approach for representing the discrete components within the system. Our approach is an extension of the Pyomo library for specifying mathematical optimization problems. Through the use of a modeling components library, the block-oriented approach facilitates a clean separation of system superstructure from the details of individual components. This approach also naturally lends itself to expressing design and operational decisions as disjunctive expressions over the component blocks. By expressing a mathematical optimization problem in a block-oriented manner, inherent structure (e.g., multiple scenarios) is preserved for potential exploitation by solvers. In particular, we show that block-structured mathematical optimization problems can be straightforwardly manipulated by decomposition-based multi-scenario algorithmic strategies, specifically in the context of the PySP stochastic programming library. We illustrate our block-oriented modeling approach using a case study drawn from the electricity grid operations domain: unit commitment with transmission switching and N - 1 reliability constraints. Finally, we demonstrate that the overhead associated with block-oriented modeling only minimally increases model instantiation times, and need not adversely impact solver behavior. (C) 2013 Elsevier Ltd. All rights reserved.

  14. Optimal Model-Based Production Planning

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    of column j) F1=Dj+Bk Successful model Example: 4 cascaded conventional columns, with 18- component feed: Ignacio Grossmann Chemical Engineering Department Carnegie Mellon University EWO Meeting ­ March 2009 #12

  15. Robust Optimization over Time A New Perspective on Dynamic Optimization Problems

    E-Print Network [OSTI]

    Yao, Xin

    the energy efficiency of turbine engines. Meanwhile, most of the real-world optimization problems are subject to various types of uncertainties. For example in stock markets, political and economical envi- ronments (NICAL), School of Computer Science and Technology, University of Science and Technology of China, Hefei

  16. Analytical modeling of balloon launch dynamics 

    E-Print Network [OSTI]

    Strganac, Thomas W

    1980-01-01

    aerodynam1cs. Actual fl1ght data has been used to qualify the model via comparisons of the launch trans1ent configurations. DEDICATION To my father. . THOMAS JOHN STRGANAC 1922-1980 . . . who provided me the examp1e to fo1Iow in life. ACKNOWLEDGEMENTS... OF TABLES. LIST OF FIGURES NOMENCLATURE. INTRODUCTION. PRESENT STATUS. DYNAMIC MODEL Forces on the Balloon. Buoyancy . Weight Distribution. Catenary . Bubble Aerodynamics, Equations of Motion. Kutta-Simpson Solution Technique NUMERICAL MODEL...

  17. THE COUPLING OF OPTIMAL ECONOMIC GROWTH AND CLIMATE DYNAMICS

    E-Print Network [OSTI]

    Edwards, Neil

    policy. The archetypal models having this structure are the DICE family of models (Nordhaus, 1993 on future implementations of these approaches in the context of "collaborative" or "commu- nity" integrated

  18. Optimal Estimation of Dynamically Evolving Di usivities Kurt S. Riedel

    E-Print Network [OSTI]

    equations to account for model error [15]. Researchers attempt to model the e#11;ect of microscopic turbulence in plasmas and uids with anomalous di#11;usion coeÆcients. These e#11;ective equations for uid ow are only an approximation of the actual evolution equations, and in many cases the model error

  19. Development of a Dynamic DOE Calibration Model | Department of...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    model was developed. The model can be applied for calibration and control system optimization. p-22anderson.pdf More Documents & Publications Reducing the Particulate Emission...

  20. Optimal Model-Based Production Planning

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    configuration Processing 2 crude oils & importing heavy naphtha Swing cut model Offers lower net cost (lighter) 142 0 Crude2 (heavier) 289 469 Other Feedstock Heavy Naphtha 13 9 Refinery Production Fuel Gas 13 Gasoline blending Distillate blending Gas oil blending Cat Crack CDU crude1 crude2 butane Fuel gas Premium

  1. Dynamic Decision Making for Graphical Models Applied to Oil Exploration

    E-Print Network [OSTI]

    Martinelli, Gabriele; Hauge, Ragnar

    2012-01-01

    We present a framework for sequential decision making in problems described by graphical models. The setting is given by dependent discrete random variables with associated costs or revenues. In our examples, the dependent variables are the potential outcomes (oil, gas or dry) when drilling a petroleum well. The goal is to develop an optimal selection strategy that incorporates a chosen utility function within an approximated dynamic programming scheme. We propose and compare different approximations, from simple heuristics to more complex iterative schemes, and we discuss their computational properties. We apply our strategies to oil exploration over multiple prospects modeled by a directed acyclic graph, and to a reservoir drilling decision problem modeled by a Markov random field. The results show that the suggested strategies clearly improve the simpler intuitive constructions, and this is useful when selecting exploration policies.

  2. Planning for multiple mobile robots in dynamic environ ments involves determining the optimal path each robot

    E-Print Network [OSTI]

    Stentz, Tony

    Abstract Planning for multiple mobile robots in dynamic environ­ ments involves determining the optimal path each robot should follow to accomplish the goals of the mission, given the current knowledge reassign robots to goals in order to continually minimize the time to complete the mission. In this paper

  3. Optimal Energy Extraction During Dynamic Jet Stream Soaring Joachim L. Grenestedt

    E-Print Network [OSTI]

    Spletzer, John R.

    1 (12) Optimal Energy Extraction During Dynamic Jet Stream Soaring Joachim L. Grenestedt and John R in the jet stream. However, the aircraft's control systems would still require electric power. This could be extracted for example using specially designed ram air turbines (RAT). The present paper focuses

  4. Characterization of control noise effects in optimal quantum unitary dynamics

    E-Print Network [OSTI]

    David Hocker; Constantin Brif; Matthew D. Grace; Ashley Donovan; Tak-San Ho; Katharine Moore Tibbetts; Rebing Wu; Herschel Rabitz

    2014-11-13

    This work develops measures for quantifying the effects of field noise upon targeted unitary transformations. Robustness to noise is assessed in the framework of the quantum control landscape, which is the mapping from the control to the unitary transformation performance measure (quantum gate fidelity). Within that framework, a new geometric interpretation of stochastic noise effects naturally arises, where more robust optimal controls are associated with regions of small overlap between landscape curvature and the noise correlation function. Numerical simulations of this overlap in the context of quantum information processing reveal distinct noise spectral regimes that better support robust control solutions. This perspective shows the dual importance of both noise statistics and the control form for robustness, thereby opening up new avenues of investigation on how to mitigate noise effects in quantum systems.

  5. An Operational Model for Optimal NonDispatchable Demand Response

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    An Operational Model for Optimal NonDispatchable Demand Response for Continuous PowerintensiveFACTS, $ Demand Response Energy Storage HVDC Industrial Customer PEV Renewable Energy Source: U.S.-Canada Power: To balance supply and demand of a power system, one can manipulate both: supply and demand demand response

  6. Modeling and Optimal Regulation of Erythropoiesis Subject to Benzene Intoxication

    E-Print Network [OSTI]

    Modeling and Optimal Regulation of Erythropoiesis Subject to Benzene Intoxication H.T. Banks1.C. 27607-5298, email: ColeC@meredith.edu December 20, 2003 Abstract Benzene (C6H6) is a highly flammable, and industrial processes. Benzene increases the incidence of leukemia in humans when they are exposed to high

  7. Modeling and Computational Strategies for Optimal Development Planning of Offshore

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    1 Modeling and Computational Strategies for Optimal Development Planning of Offshore Oilfields for offshore oil and gas fields as a basis to include the generic fiscal rules with ringfencing provisions-integer programming. 1 Introduction Offshore oil and gas field development planning has received significant attention

  8. Optimal control of a dengue epidemic model with vaccination

    E-Print Network [OSTI]

    Rodrigues, Helena Sofia; Torres, Delfim F M

    2011-01-01

    We present a SIR+ASI epidemic model to describe the interaction between human and dengue fever mosquito populations. A control strategy in the form of vaccination, to decrease the number of infected individuals, is used. An optimal control approach is applied in order to find the best way to fight the disease.

  9. Silvya Dewi Rahmawati Integrated Field Modeling and Optimization

    E-Print Network [OSTI]

    Foss, Bjarne A.

    Technology, Mathematics and Electrical Engineering Department of Engineering Cybernetics #12;ii Summary Oil of philosophiae doctor Trondheim, March 2012 Norwegian University of Science and Technology Faculty of Information with optimization presents many technological challenges in terms efficient algorithms to couple models, as well

  10. Optimization Models for Shale Gas Water Management Linlin Yang

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    Optimization Models for Shale Gas Water Management Linlin Yang , Jeremy Manno and Ignacio E With the advancement in directional drilling and hydraulic fracturing, shale gas is predicted to provide 46% of the United States natural gas supply by 20351 . The number of wells drilled in the Marcellus shale play has

  11. Surrogate modeling based on statistical techniques for multi-fidelity optimization

    E-Print Network [OSTI]

    Lam, Rémi

    2014-01-01

    Designing and optimizing complex systems generally requires the use of numerical models. However, it is often too expensive to evaluate these models at each step of an optimization problem. Instead surrogate models can be ...

  12. Stochastic dynamic optimization of consumption and the induced price elasticity of demand in smart grids

    E-Print Network [OSTI]

    Faghih, Ali

    2011-01-01

    This thesis presents a mathematical model of consumer behavior in response to stochastically-varying electricity prices, and a characterization of price-elasticity of demand created by optimal utilization of storage and ...

  13. Modeling of Reactor Kinetics and Dynamics

    SciTech Connect (OSTI)

    Matthew Johnson; Scott Lucas; Pavel Tsvetkov

    2010-09-01

    In order to model a full fuel cycle in a nuclear reactor, it is necessary to simulate the short time-scale kinetic behavior of the reactor as well as the long time-scale dynamics that occur with fuel burnup. The former is modeled using the point kinetics equations, while the latter is modeled by coupling fuel burnup equations with the kinetics equations. When the equations are solved simultaneously with a nonlinear equation solver, the end result is a code with the unique capability of modeling transients at any time during a fuel cycle.

  14. DYNAMIC MODELING PROTON EXCHANGE MEMBRANE FUEL CELL

    E-Print Network [OSTI]

    Mease, Kenneth D.

    DYNAMIC MODELING PROTON EXCHANGE MEMBRANE FUEL CELL OVERVIEW Current/Completed Plug Power to garner SCAQMD funding for fuel cell testing GenCore system is sensitive to diluents · As built design stream to compensate for removal of EGR · Functionality of the modified GenCore Fuel Cell system

  15. Feature extraction for structural dynamics model validation

    SciTech Connect (OSTI)

    Hemez, Francois [Los Alamos National Laboratory; Farrar, Charles [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory; Nishio, Mayuko [UNIV OF TOKYO; Worden, Keith [UNIV OF SHEFFIELD; Takeda, Nobuo [UNIV OF TOKYO

    2010-11-08

    This study focuses on defining and comparing response features that can be used for structural dynamics model validation studies. Features extracted from dynamic responses obtained analytically or experimentally, such as basic signal statistics, frequency spectra, and estimated time-series models, can be used to compare characteristics of structural system dynamics. By comparing those response features extracted from experimental data and numerical outputs, validation and uncertainty quantification of numerical model containing uncertain parameters can be realized. In this study, the applicability of some response features to model validation is first discussed using measured data from a simple test-bed structure and the associated numerical simulations of these experiments. issues that must be considered were sensitivity, dimensionality, type of response, and presence or absence of measurement noise in the response. Furthermore, we illustrate a comparison method of multivariate feature vectors for statistical model validation. Results show that the outlier detection technique using the Mahalanobis distance metric can be used as an effective and quantifiable technique for selecting appropriate model parameters. However, in this process, one must not only consider the sensitivity of the features being used, but also correlation of the parameters being compared.

  16. Switched Dynamical Latent Force Models for Modelling Transcriptional Regulation

    E-Print Network [OSTI]

    López-Lopera, Andrés F

    2015-01-01

    In order to develop statistical approaches for transcription networks, statistical community has proposed several methods to infer activity levels of proteins, from time-series measurements of targets' expression levels. A few number of approaches have been proposed in order to outperform the representation of fast switching time instants, but computational overheads are significant due to complex inference algorithms. Using the theory related to latent force models (LFM), the development of this project provide a switched dynamical hybrid model based on Gaussian processes (GPs). To deal with discontinuities in dynamical systems (or latent driving force), an extension of the single input motif approach is introduced, that switches between different protein concentrations, and different dynamical systems. This creates a versatile representation for transcription networks that can capture discrete changes and non-linearities in the dynamics. The proposed method is evaluated on both simulated data and real data,...

  17. Traffic Optimization to Control Epidemic Outbreaks in Metapopulation Models

    E-Print Network [OSTI]

    Preciado, Victor M

    2013-01-01

    We propose a novel framework to study viral spreading processes in metapopulation models. Large subpopulations (i.e., cities) are connected via metalinks (i.e., roads) according to a metagraph structure (i.e., the traffic infrastructure). The problem of containing the propagation of an epidemic outbreak in a metapopulation model by controlling the traffic between subpopulations is considered. Controlling the spread of an epidemic outbreak can be written as a spectral condition involving the eigenvalues of a matrix that depends on the network structure and the parameters of the model. Based on this spectral condition, we propose a convex optimization framework to find cost-optimal approaches to traffic control in epidemic outbreaks.

  18. FLUID DYNAMICAL AND MODELING ISSUES OF CHEMICAL FLOODING FOR ENHANCED OIL RECOVERY

    E-Print Network [OSTI]

    Daripa, Prabir

    of the objective functions in tertiary oil recovery by polymer flooding is the "op- timal" viscous profileFLUID DYNAMICAL AND MODELING ISSUES OF CHEMICAL FLOODING FOR ENHANCED OIL RECOVERY Prabir Daripa are succinctly summarized including characteri- zation of the optimal flooding scheme that leads to maximum oil

  19. Optimal threshold policies in a workload model with a variable number of service phases per job

    E-Print Network [OSTI]

    Brouns, Gido

    and termination control, optimal threshold policies, Markov decision processes. 1 Introduction Workload models of performance optimization is the question of how to control some type of system in an optimal way within in literature so far. Stidham and Weber 4 present a comprehensive overview of models for the optimal control

  20. Dynamical cooling of a single-reservoir open quantum system via optimal control

    E-Print Network [OSTI]

    Schmidt, Rebecca; Ankerhold, Joachim; Calarco, Tommaso; Stockburger, Jürgen T

    2010-01-01

    Based on an exact description of open quantum systems in terms of stochastic Liouville-von Neumann equations optimal control is investigated without rotating-wave or Markovian approximations. Within this scheme we generalize Krotov's iterative algorithm, preserving its monotonic convergence. This formalism is applied to the problem of controlling a particle in a harmonic potential whose thermal bath is characterized by an ohmic spectrum. Interestingly, optimal control can modify the quantum dissipative dynamics to the point where its entropy change turns negative. We provide an example where translational motion is cooled without any involvement of internal degrees of freedom.

  1. Design method of dynamical decoupling sequences integrated with optimal control theory

    E-Print Network [OSTI]

    Yutaka Tabuchi; Masahiro Kitagawa

    2012-08-26

    A method for synthesizing dynamical decoupling (DD) sequences is presented, which can tailor these sequences to a given set of qubits, environments, instruments, and available resources using partial information of the system. The key concept behind the generation of the DD sequences involves not only extricating the strong dependence on the coupling strengths according to the "optimal control," but also exploiting the "refocus" technique used conventionally to obtain DD sequences. The concept is a generalized one that integrates optimal control and designing of DD sequences.

  2. Hybrid fuzzy and optimal modeling for water quality evaluation 

    E-Print Network [OSTI]

    Wang, Dong; Singh, Vijay P.; Zhu, Yuansheng

    2007-05-08

    modeling for water quality evaluation Dong Wang, 1 Vijay P. Singh, 2 and Yuansheng Zhu 3 Received 1 September 2006; revised 16 December 2006; accepted 19 January 2007; published 8 May 2007. [1] Water quality evaluation entails both randomness and fuzziness..., the proposed models are flexible and adaptable for diagnosing the eutrophic status. Citation: Wang, D., V. P. Singh, and Y. Zhu (2007), Hybrid fuzzy and optimal modeling for water quality evaluation, Water Resour. Res., 43, W05415, doi:10.1029/2006WR005490. 1...

  3. Transactions in GIS Dynamic Modelling and Visualization on the Internet

    E-Print Network [OSTI]

    Worboys, Mike

    1 Transactions in GIS Dynamic Modelling and Visualization on the Internet Bo Huang* and Michael F for GIS to incorporate dynamic analytic models. At the same time, there is a need to distribute results of dynamic GIS using the Internet. Therefore, this paper sets out to explore the implementation of dynamic

  4. System Modeling, Analysis, and Optimization Methodology for Diesel Exhaust After-treatment Technologies

    E-Print Network [OSTI]

    de Weck, Olivier L.

    System Modeling, Analysis, and Optimization Methodology for Diesel Exhaust After;System Modeling, Analysis, and Optimization Methodology for Diesel Exhaust After-treatment Technologies Developing new aftertreatment technologies to meet emission regulations for diesel engines is a growing

  5. Hour-by-Hour Cost Modeling of Optimized Central Wind-Based Water...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hour-by-Hour Cost Modeling of Optimized Central Wind-Based Water Electrolysis Production Hour-by-Hour Cost Modeling of Optimized Central Wind-Based Water Electrolysis Production...

  6. Optimal Model of Distributed Energy System by Using GAMS and Case Study

    E-Print Network [OSTI]

    Yang, Yongwen; Gao, Weijun; Ruan, Yingjun; Xuan, Ji; Zhou, Nan; Marnay, Chris

    2005-01-01

    Optimal Model of Distributed Energy System by Using GAMS andEnergy Reliability, Distributed Energy Program of the U.S.Optimal Model of Distributed Energy System by Using GAMS and

  7. A Dynamic Network Oligopoly Model Transportation Costs, Product Differentiation,

    E-Print Network [OSTI]

    Nagurney, Anna

    of Operations & Information Management Isenberg School of Management University of Massachusetts AmherstA Dynamic Network Oligopoly Model with Transportation Costs, Product Differentiation, and Quality of Massachusetts Amherst A Dynamic Network Oligopoly Model with Quality Competition #12;Acknowledgments

  8. Modeling Dynamics of Post Disaster Recovery 

    E-Print Network [OSTI]

    Nejat, Ali

    2012-10-19

    : Civil Engineering MODELING DYNAMICS OF POST DISASTER RECOVERY A Dissertation by ALI NEJAT Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR... OF PHILOSOPHY Approved by: Chair of Committee, Ivan Damnjanovic Committee Members, Stuart D. Anderson Kenneth F. Reinschmidt Sergiy Butenko Arnold Vedlitz Head of Department, John Niedzwecki August 2011 Major Subject: Civil Engineering...

  9. Regional Dynamics Model (REDYN) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onRAPID/Geothermal/Exploration/Colorado <RAPID/Geothermal/WaterEnergyRedfield1989) Jump to:|OpenRegenesisDynamics Model

  10. Cooperating or Fighting with Decoherence in the Optimal Control of Quantum Dynamics

    E-Print Network [OSTI]

    Shuang, F; Shuang, Feng; Rabitz, Herschel

    2006-01-01

    This paper explores the use of laboratory closed-loop learning control to either fight or cooperate with decoherence in the optimal manipulation of quantum dynamics. Simulations of the processes are performed in a Lindblad formulation on multilevel quantum systems strongly interacting with the environment without spontaneous emission. When seeking a high control yield it is possible to find fields that successfully fight with decoherence while attaining a good quality yield. When seeking modest control yields, fields can be found which are optimally shaped to cooperate with decoherence and thereby drive the dynamics more efficiently. In the latter regime when the control field and the decoherence strength are both weak, a theoretical foundation is established to describe how they cooperate with each other. In general, the results indicate that the population transfer objectives can be effectively met by appropriately either fighting or cooperating with decoherence.

  11. Cooperating or Fighting with Decoherence in the Optimal Control of Quantum Dynamics

    E-Print Network [OSTI]

    Feng Shuang; Herschel Rabitz

    2006-06-20

    This paper explores the use of laboratory closed-loop learning control to either fight or cooperate with decoherence in the optimal manipulation of quantum dynamics. Simulations of the processes are performed in a Lindblad formulation on multilevel quantum systems strongly interacting with the environment without spontaneous emission. When seeking a high control yield it is possible to find fields that successfully fight with decoherence while attaining a good quality yield. When seeking modest control yields, fields can be found which are optimally shaped to cooperate with decoherence and thereby drive the dynamics more efficiently. In the latter regime when the control field and the decoherence strength are both weak, a theoretical foundation is established to describe how they cooperate with each other. In general, the results indicate that the population transfer objectives can be effectively met by appropriately either fighting or cooperating with decoherence.

  12. DYNAMICAL MODELING OF GALAXY MERGERS USING IDENTIKIT

    SciTech Connect (OSTI)

    Privon, G. C.; Evans, A. S.; Barnes, J. E.; Hibbard, J. E.; Yun, M. S.; Mazzarella, J. M.; Armus, L.; Surace, J.

    2013-07-10

    We present dynamical models of four interacting systems: NGC 5257/8, The Mice, the Antennae, and NGC 2623. The parameter space of the encounters are constrained using the Identikit model-matching and visualization tool. Identikit utilizes hybrid N-body and test particle simulations to enable rapid exploration of the parameter space of galaxy mergers. The Identikit-derived matches of these systems are reproduced with self-consistent collisionless simulations which show very similar results. The models generally reproduce the observed morphology and H I kinematics of the tidal tails in these systems with reasonable properties inferred for the progenitor galaxies. The models presented here are the first to appear in the literature for NGC 5257/8 and NGC 2623, and The Mice and the Antennae are compared with previously published models. Based on the assumed mass model and our derived initial conditions, the models indicate that the four systems are currently being viewed 175-260 Myr after first passage and cover a wide range of merger stages. In some instances there are mismatches between the models and the data (e.g., in the length of a tail); these are likely due to our adoption of a single mass model for all galaxies. Despite the use of a single mass model, these results demonstrate the utility of Identikit in constraining the parameter space for galaxy mergers when applied to real data.

  13. Optimal Control of Quantum Dissipative Dynamics: Analytic solution for cooling the three level $?$ system

    E-Print Network [OSTI]

    Shlomo E. Sklarz; David J. Tannor; Navin Khaneja

    2004-02-19

    We study the problem of optimal control of dissipative quantum dynamics. Although under most circumstances dissipation leads to an increase in entropy (or a decrease in purity) of the system, there is an important class of problems for which dissipation with external control can decrease the entropy (or increase the purity) of the system. An important example is laser cooling. In such systems, there is an interplay of the Hamiltonian part of the dynamics, which is controllable and the dissipative part of the dynamics, which is uncontrollable. The strategy is to control the Hamiltonian portion of the evolution in such a way that the dissipation causes the purity of the system to increase rather than decrease. The goal of this paper is to find the strategy that leads to maximal purity at the final time. Under the assumption that Hamiltonian control is complete and arbitrarily fast, we provide a general framework by which to calculate optimal cooling strategies. These assumptions lead to a great simplification, in which the control problem can be reformulated in terms of the spectrum of eigenvalues of $\\rho$, rather than $\\rho$ itself. By combining this formulation with the Hamilton-Jacobi-Bellman theorem we are able to obtain an equation for the globaly optimal cooling strategy in terms of the spectrum of the density matrix. For the three-level $\\Lambda$ system, we provide a complete analytic solution for the optimal cooling strategy. For this system it is found that the optimal strategy does not exploit system coherences and is a 'greedy' strategy, in which the purity is increased maximally at each instant.

  14. MATH 4/5794 Mathematical Modeling Demonstrations % MATH 4/5794: Optimization Modeling

    E-Print Network [OSTI]

    Lodwick, Weldon

    :'; ************************************************************ ************************************************************ *********** Multiple Sclerosis Plaque Detection ************ ************************************************************ ************************************************************ % MATH 4/5794: Optimization Modeling % EXAMPLES: W. A. Lodwick - Example 1, Multiple Sclerosis Plaque Detection % Example 2, Multiple Sclerosis Plaque Detection % Example 3, Multiple Sclerosis Plaque Detection

  15. Performance monitoring for new phase dynamic optimization of instruction dispatch cluster configuration

    DOE Patents [OSTI]

    Balasubramonian, Rajeev (Sandy, UT); Dwarkadas, Sandhya (Rochester, NY); Albonesi, David (Ithaca, NY)

    2012-01-24

    In a processor having multiple clusters which operate in parallel, the number of clusters in use can be varied dynamically. At the start of each program phase, the configuration option for an interval is run to determine the optimal configuration, which is used until the next phase change is detected. The optimum instruction interval is determined by starting with a minimum interval and doubling it until a low stability factor is reached.

  16. Sensitivity Analysis of a Dynamic Fleet Management Model Using Approximate Dynamic Programming

    E-Print Network [OSTI]

    Topaloglu, Huseyin

    of fleet management models is to make the vehicle repositioning and vehicle-to-load assignment decisions soSensitivity Analysis of a Dynamic Fleet Management Model Using Approximate Dynamic Programming present tractable algorithms to assess the sensitivity of a stochastic dynamic fleet management model

  17. Optimizing ZigBee Security using Stochastic Model Checking

    E-Print Network [OSTI]

    Yüksel, Ender; Nielson, Flemming; Fruth, Matthias; Kwiatkowska, Marta

    2012-01-01

    ZigBee is a fairly new but promising wireless sensor network standard that offers the advantages of simple and low resource communication. Nevertheless, security is of great concern to ZigBee, and enhancements are prescribed in the latest ZigBee specication: ZigBee-2007. In this technical report, we identify an important gap in the specification on key updates, and present a methodology for determining optimal key update policies and security parameters. We exploit the stochastic model checking approach using the probabilistic model checker PRISM, and assess the security needs for realistic application scenarios.

  18. Restoration of the Potosi Dynamic Model 2010

    SciTech Connect (OSTI)

    Adushita, Yasmin; Leetaru, Hannes

    2014-09-30

    In topical Report DOE/FE0002068-1 [2] technical performance evaluations on the Cambrian Potosi Formation were performed through reservoir modeling. The data included formation tops from mud logs, well logs from the VW1 and the CCS1 wells, structural and stratigraphic formation from three dimensional (3D) seismic data, and field data from several waste water injection wells for Potosi Formation. Intention was for two million tons per annum (MTPA) of CO2 to be injected for 20 years. In this Task the 2010 Potosi heterogeneous model (referred to as the "Potosi Dynamic Model 2010" in this report) was re-run using a new injection scenario; 3.2 MTPA for 30 years. The extent of the Potosi Dynamic Model 2010, however, appeared too small for the new injection target. It was not sufficiently large enough to accommodate the evolution of the plume. Also, it might have overestimated the injection capacity by enhancing too much the pressure relief due to the relatively close proximity between the injector and the infinite acting boundaries. The new model, Potosi Dynamic Model 2013a, was built by extending the Potosi Dynamic Model 2010 grid to 30 miles x 30 miles (48 km by 48 km), while preserving all property modeling workflows and layering. This model was retained as the base case. Potosi Dynamic Model 2013.a gives an average CO2 injection rate of 1.4 MTPA and cumulative injection of 43 Mt in 30 years, which corresponds to 45% of the injection target. This implies that according to this preliminary model, a minimum of three (3) wells could be required to achieve the injection target. The injectivity evaluation of the Potosi formation will be revisited in topical Report 15 during which more data will be integrated in the modeling exercise. A vertical flow performance evaluation could be considered for the succeeding task to determine the appropriate tubing size, the required injection tubing head pressure (THP) and to investigate whether the corresponding well injection rate falls within the tubing erosional velocity limit. After 30 years, the plume extends 15 miles (24 km) in E-W and 14 miles (22 km) in N-S directions. After injection is completed, the plume continues to migrate laterally, mainly driven by the remaining pressure gradient. After 100 years post-injection, the plume extends 17 miles (27 km) in E-W and 15 miles (24 km) in N-S directions. The increase of reservoir pressure at the end of injection is approximately 370 psia around the injector and gradually decreases away from the well. The reservoir pressure increase is less than 30 psia beyond 14 miles (22 km) away from injector. The initial reservoir pressure is restored after approximately 20 years post-injection. This result, however, is associated with uncertainties on the boundary conditions, and a sensitivity analysis could be considered for the succeeding tasks. It is important to remember that the respective plume extent and areal pressure increase corresponds to an injection of 43 Mt CO2. Should the targeted cumulative injection of 96 Mt be achieved; a much larger plume extent and areal pressure increase could be expected. Re-evaluating the permeability modeling, vugs and heterogeneity distributions, and relative permeability input could be considered for the succeeding Potosi formation evaluations. A simulation using several injectors could also be considered to determine the required number of wells to achieve the injection target while taking into account the pressure interference.

  19. AFDM: An Advanced Fluid-Dynamics Model

    SciTech Connect (OSTI)

    Bohl, W.R.; Parker, F.R. (Los Alamos National Lab., NM (USA)); Wilhelm, D. (Kernforschungszentrum Karlsruhe GmbH (Germany, F.R.). Inst. fuer Neutronenphysik und Reaktortechnik); Berthier, J. (CEA Centre d'Etudes Nucleaires de Grenoble, 38 (France)); Goutagny, L. (CEA Centre d'Etudes Nucleaires de Cadarache, 13 - Saint-Paul-lez-Durance (France). Inst. de Protection et de Surete Nucleaire); Ninokata,

    1990-09-01

    AFDM, or the Advanced Fluid-Dynamics Model, is a computer code that investigates new approaches simulating the multiphase-flow fluid-dynamics aspects of severe accidents in fast reactors. The AFDM formalism starts with differential equations similar to those in the SIMMER-II code. These equations are modified to treat three velocity fields and supplemented with a variety of new models. The AFDM code has 12 topologies describing what material contacts are possible depending on the presence or absence of a given material in a computational cell, on the dominant liquid, and on the continuous phase. Single-phase, bubbly, churn-turbulent, cellular, and dispersed flow regimes are permitted for the pool situations modeled. Virtual mass terms are included for vapor in liquid-continuous flow. Interfacial areas between the continuous and discontinuous phases are convected to allow some tracking of phenomenological histories. Interfacial areas are also modified by models of nucleation, dynamic forces, turbulence, flashing, coalescence, and mass transfer. Heat transfer is generally treated using engineering correlations. Liquid-vapor phase transitions are handled with the nonequilibrium, heat-transfer-limited model, whereas melting and freezing processes are based on equilibrium considerations. Convection is treated using a fractional-step method of time integration, including a semi-implicit pressure iteration. A higher-order differencing option is provided to control numerical diffusion. The Los Alamos SESAME equation-of-state has been implemented using densities and temperatures as the independent variables. AFDM programming has vectorized all computational loops consistent with the objective of producing an exportable code. 24 refs., 4 figs.

  20. A Game-Theoretical Dynamic Model for Electricity Markets

    E-Print Network [OSTI]

    Oct 6, 2010 ... Abstract: We present a game-theoretical dynamic model for competitive electricity markets.We demonstrate that the model can be used to ...

  1. Dislocation dynamics: from microscopic models to macroscopic crystal plasticity

    E-Print Network [OSTI]

    Hajj, A El; Monneau, R

    2009-01-01

    In this paper we study the connection between four models describing dislocation dynamics: a generalized 2D Frenkel-Kontorova model at the atomic level, the Peierls-Nabarro model, the discrete dislocation dynamics and a macroscopic model with dislocation densities. We show how each model can be deduced from the previous one at a smaller scale.

  2. Overview of the synergia 3-D multi-particle dynamics modeling framework

    SciTech Connect (OSTI)

    Spentzouris, P.; Amundson, J.F.; Dechow, D.R.; /Tech-X, Boulder

    2005-05-01

    High precision modeling of space-charge effects is essential for designing future accelerators as well as optimizing the performance of existing machines. Synergia is a high-fidelity parallel beam dynamics simulation package with fully three dimensional space-charge capabilities and a higher-order optics implementation. We describe the Synergia framework and model benchmarks we obtained by comparing to semi-analytic results and other codes. We also present Synergia simulations of the Fermilab Booster accelerator and comparisons with experiment.

  3. Efficient Nonlinear Optimization with Rigorous Models for Large Scale Industrial Chemical Processes 

    E-Print Network [OSTI]

    Zhu, Yu

    2011-08-08

    of Department, Michael Pishko May 2011 Major Subject: Chemical Engineering iii ABSTRACT Efficient Nonlinear Optimization with Rigorous Models for Large Scale Industrial Chemical Processes. (May 2011) Yu Zhu, B.S., Zhejiang University; M.S., Zhejiang... . . . . . . . . . . . . . . . . . . . . . . . . . . 1 A. Nonlinear Optimization with Rigorous Large Scale Models 1 B. Chemical Applications of Nonlinear Optimization . . . . . 2 1. Design under Uncertainty . . . . . . . . . . . . . . . . 3 2. Optimal Operations with Steady State Models . . . . 4...

  4. Dynamical model for light composite fermions

    SciTech Connect (OSTI)

    Derman, E.

    1981-04-01

    A simple dynamical model for the internal structure of the three light lepton and quark generations (..nu../sub e/,e,u,d), (..nu../sub ..mu../,..mu..,c,s), and (..nu../sub tau/,tau,t,b) is proposed. Each generation is constructed of only one fundamental massive generation F=(L-italic/sup 0/,L/sup -/,U,D) with the same (SU/sub 3/)/sub c/ x SU/sub 2/ x U/sub 1/ quantum numbers as the light generations, bound to a core of one or more massive Higgs bosons H, where H is the single physical Higgs boson necessary for spontaneous symmetry breaking in the standard model. For example, e/sup -/=L/sup -/H), ..mu../sup -/=L/sup -/HH), tau/sup -/=L/sup -/HHH). It is shown that the known binding force due to H exchange is attractive and strong enough to produce light bound states. Dynamical calculations for the bound-state composite fermions using the Bethe-Salpeter equation, together with some phenomenological imput, suggest M/sub H/approx.16 TeV and M/sub F/approx.100 GeV. It is likely that such bound states can have properties compatible with the up to now apparently elementary appearance of known fermions, for example, their Dirac magnetic moments and absence of intergeneration radiative decays (such as ..mu -->..e..gamma..). Phenomenological consequences and tests of the model are discussed.

  5. Dynamical Systems Analysis of Various Dark Energy Models

    E-Print Network [OSTI]

    Nandan Roy

    2015-11-25

    In this thesis, we used dynamical systems analysis to find the qualitative behaviour of some dark energy models. Specifically, dynamical systems analysis of quintessence scalar field models, chameleon scalar field models and holographic models of dark energy are discussed in this thesis.

  6. Dynamical Systems Analysis of Various Dark Energy Models

    E-Print Network [OSTI]

    Roy, Nandan

    2015-01-01

    In this thesis, we used dynamical systems analysis to find the qualitative behaviour of some dark energy models. Specifically, dynamical systems analysis of quintessence scalar field models, chameleon scalar field models and holographic models of dark energy are discussed in this thesis.

  7. Prerequisites Control Systems, System Modeling, Optimal Control, Model Predictive Control, (Engine Systems).

    E-Print Network [OSTI]

    Lygeros, John

    of High Performance Hybrid Race Cars Background The power unit of a high performance hybrid race carPrerequisites Control Systems, System Modeling, Optimal Control, Model Predictive Control, (Engine consists of an internal combustion engine (ICE) and a kinetic energy recovery system (KERS). The time

  8. Data-Driven Optimization for Modeling in Computer Graphics and Vision

    E-Print Network [OSTI]

    Yu, Lap Fai

    2013-01-01

    optimization problem, including: Explicit Control: Users can have explicit control over the modeling process,process while having close, interactive control. For example, in the Clutterbrush project, an optimization-

  9. Linking Dynamical and Population Genetic Models of Persistent Viral Infection

    E-Print Network [OSTI]

    Kelly, John K.; Williamson, Scott; Orive, Maria E.; Smith, Marilyn S.; Holt, Robert D.

    2003-07-01

    This article develops a theoretical framework to link dynamical and population genetic models of persistent viral infection. This linkage is useful because, while the dynamical and population genetic theories have developed ...

  10. 866 IEEE TRANSACTIONS ON MAGNETICS, VOL. 44, NO. 6, JUNE 2008 Dynamical Models for Eddy Current in Ferromagnetic Cores Introduced in

    E-Print Network [OSTI]

    Boyer, Edmond

    866 IEEE TRANSACTIONS ON MAGNETICS, VOL. 44, NO. 6, JUNE 2008 Dynamical Models for Eddy Current accurate dynamical models for representing eddy currents are studied. The simulation of the relay is provided. Index Terms--AC circuit breakers (CBs), eddy currents, magnetic hysteresis, optimization methods

  11. AFDM: An Advanced Fluid-Dynamics Model

    SciTech Connect (OSTI)

    Berthier, J. (CEA Centre d'Etudes Nucleaires de Grenoble, 38 (France)); Wilhelm, D. (Kernforschungszentrum Karlsruhe GmbH (Germany, F.R.). Inst. fuer Neutronenphysik und Reaktortechnik); Bohl, W.R. (Los Alamos National Lab., NM (USA))

    1990-09-01

    This report consists of three parts. First, for the standard Advanced Fluid-Dynamics Model (AFDM), heat-transfer coefficients between components are worked out, depending on the different possible topologies. Conduction, convection, and radiative heat-transfer mechanisms are modeled. For solid particles, discontinuous phases that obey a rigid'' model, and components lacking relative motion, heat transfer is by conduction. Convection is represented for fluids in motion inside circulating'' bubbles and/or droplets. Radiation is considered between droplets in vapor continuous flow. In addition, a film-boiling model has been formulated, where radiation provides the lower limit on the fuel-to-coolant heat-transfer coefficient. Second, the momentum-exchange coefficients are defined for the standard AFDM. Between a continuous and discontinuous phase, the model consists of both laminar and turbulent terms. The most important feature is the drag coefficient in the turbulent term. It is calculated by a drag similarity hypothesis with limits for large Reynolds numbers, distorted particles,'' and churn-turbulent flow. A unique hysteresis algorithm exists to treat the liquid continuous to vapor continuous transition. Two discontinuous components are coupled using a turbulent term with an input drag coefficient. Fluid- structure momentum exchange is represented with a standard friction-factor correlation. Third, the formulas used for the AFDM simplified Step 1 models are discussed. These include the heat-transfer coefficients, the momentum-exchange functions, and the manner in which interfacial areas are determined from input length scales. The simplified modeling uses steady-state engineering correlations, as in SIMMER-II.

  12. Toward a mechanistic modeling of nitrogen limitation on vegetation dynamics

    SciTech Connect (OSTI)

    Xu, Chonggang [Los Alamos National Laboratory (LANL); Fisher, Rosie [National Center for Atmospheric Research (NCAR); Wullschleger, Stan D [ORNL; Wilson, Cathy [Los Alamos National Laboratory (LANL); Cai, Michael [Los Alamos National Laboratory (LANL); McDowell, Nathan [Los Alamos National Laboratory (LANL)

    2012-01-01

    Nitrogen is a dominant regulator of vegetation dynamics, net primary production, and terrestrial carbon cycles; however, most ecosystem models use a rather simplistic relationship between leaf nitrogen content and photosynthetic capacity. Such an approach does not consider how patterns of nitrogen allocation may change with differences in light intensity, growing-season temperature and CO{sub 2} concentration. To account for this known variability in nitrogen-photosynthesis relationships, we develop a mechanistic nitrogen allocation model based on a trade-off of nitrogen allocated between growth and storage, and an optimization of nitrogen allocated among light capture, electron transport, carboxylation, and respiration. The developed model is able to predict the acclimation of photosynthetic capacity to changes in CO{sub 2} concentration, temperature, and radiation when evaluated against published data of V{sub c,max} (maximum carboxylation rate) and J{sub max} (maximum electron transport rate). A sensitivity analysis of the model for herbaceous plants, deciduous and evergreen trees implies that elevated CO{sub 2} concentrations lead to lower allocation of nitrogen to carboxylation but higher allocation to storage. Higher growing-season temperatures cause lower allocation of nitrogen to carboxylation, due to higher nitrogen requirements for light capture pigments and for storage. Lower levels of radiation have a much stronger effect on allocation of nitrogen to carboxylation for herbaceous plants than for trees, resulting from higher nitrogen requirements for light capture for herbaceous plants. As far as we know, this is the first model of complete nitrogen allocation that simultaneously considers nitrogen allocation to light capture, electron transport, carboxylation, respiration and storage, and the responses of each to altered environmental conditions. We expect this model could potentially improve our confidence in simulations of carbon-nitrogen interactions and the vegetation feedbacks to climate in Earth system models.

  13. Implications of a Regime-Switching Model on Natural Gas Storage Valuation and Optimal Operation

    E-Print Network [OSTI]

    Forsyth, Peter A.

    Implications of a Regime-Switching Model on Natural Gas Storage Valuation and Optimal Operation-switching model for the risk adjusted natural gas spot price and study the implications of the model on the valuation and optimal operation of natural gas storage facilities. We calibrate the model parameters to both

  14. Demonstration of Open Quantum System Optimal Control in Dynamic Nuclear Polarization

    E-Print Network [OSTI]

    Sarah Sheldon; David G. Cory

    2015-07-09

    Dynamic nuclear polarization (DNP) is used in nuclear magnetic resonance (NMR) to transfer polarization from electron spins to nuclear spins. The resulting nuclear polarization enhancement can, in theory, be two or three orders of magnitude depending on the sample. In solid state systems, however, there are competing mechanisms of DNP, which, when occurring simultaneously, reduce the net polarization enhancement of the nuclear spin. We present a simple quantum description of DNP and apply optimal control theory (OCT) with an open quantum system framework to design pulses that select one DNP process and suppress the others. We demonstrate experimentally an order of magnitude improvement in the DNP enhancement using OCT pulses.

  15. Demonstration of Open Quantum System Optimal Control in Dynamic Nuclear Polarization

    E-Print Network [OSTI]

    Sarah Sheldon; David G. Cory

    2015-07-20

    Dynamic nuclear polarization (DNP) is used in nuclear magnetic resonance (NMR) to transfer polarization from electron spins to nuclear spins. The resulting nuclear polarization enhancement can, in theory, be two or three orders of magnitude depending on the sample. In solid state systems, however, there are competing mechanisms of DNP, which, when occurring simultaneously, reduce the net polarization enhancement of the nuclear spin. We present a simple quantum description of DNP and apply optimal control theory (OCT) with an open quantum system framework to design pulses that select one DNP process and suppress the others. We demonstrate experimentally an order of magnitude improvement in the DNP enhancement using OCT pulses.

  16. A Parallelizable and Approximate Dynamic Programming-Based Dynamic Fleet Management Model with

    E-Print Network [OSTI]

    Topaloglu, Huseyin

    -based dynamic fleet management model that can handle random load arrivals, random travel times and multiple-based model for the dynamic fleet management problem with random load arrivals, random travel times-based models for fleet management problems with random load arrivals, deterministic travel times and a single

  17. Solid Oxide Fuel Cell: Perspective of Dynamic Modeling and Control

    E-Print Network [OSTI]

    Huang, Biao

    Solid Oxide Fuel Cell: Perspective of Dynamic Modeling and Control Biao Huang Yutong Qi Monjur: This paper presents a review of state-of-the-art solid oxide fuel cells (SOFC), from perspective of dynamic. Keywords: Solid Oxide Fuel Cell, Control Relevant Model, Model Predictive Control 1. INTRODUCTION Today

  18. Characteristics of identifying linear dynamic models from impulse response data using Prony analysis

    SciTech Connect (OSTI)

    Trudnowski, D.J.

    1992-12-01

    The purpose of the study was to investigate the characteristics of fitting linear dynamic models to the impulse response of oscillatory dynamic systems using Prony analysis. Many dynamic systems exhibit oscillatory responses with multiple modes of oscillations. Although the underlying dynamics of such systems are often nonlinear, it is frequently possible and very useful to represent the system operating about some set point with a linear model. Derivation of such linear models can be done using two basic approaches: model the system using theoretical derivations and some linearization method such as a Taylor series expansion; or use a curve-fitting technique to optimally fit a linear model to specified system response data. Prony analysis belongs to the second class of system modeling because it is a method of fitting a linear model to the impulse response of a dynamic system. Its parallel formulation inherently makes it well suited for fitting models to oscillatory system data. Such oscillatory dynamic effects occur in large synchronous-generator-based power systems in the form of electromechanical oscillations. To study and characterize these oscillatory dynamics, BPA has developed computer codes to analyze system data using Prony analysis. The objective of this study was to develop a highly detailed understanding of the properties of using Prony analysis to fit models to systems with characteristics often encountered in power systems. This understanding was then extended to develop general rules-of-thumb'' for using Prony analysis. The general characteristics were investigated by performing fits to data from known linear models under controlled conditions. The conditions studied include various mathematical solution techniques; different parent system configurations; and a large variety of underlying noise characteristics.

  19. Characteristics of identifying linear dynamic models from impulse response data using Prony analysis

    SciTech Connect (OSTI)

    Trudnowski, D.J.

    1992-12-01

    The purpose of the study was to investigate the characteristics of fitting linear dynamic models to the impulse response of oscillatory dynamic systems using Prony analysis. Many dynamic systems exhibit oscillatory responses with multiple modes of oscillations. Although the underlying dynamics of such systems are often nonlinear, it is frequently possible and very useful to represent the system operating about some set point with a linear model. Derivation of such linear models can be done using two basic approaches: model the system using theoretical derivations and some linearization method such as a Taylor series expansion; or use a curve-fitting technique to optimally fit a linear model to specified system response data. Prony analysis belongs to the second class of system modeling because it is a method of fitting a linear model to the impulse response of a dynamic system. Its parallel formulation inherently makes it well suited for fitting models to oscillatory system data. Such oscillatory dynamic effects occur in large synchronous-generator-based power systems in the form of electromechanical oscillations. To study and characterize these oscillatory dynamics, BPA has developed computer codes to analyze system data using Prony analysis. The objective of this study was to develop a highly detailed understanding of the properties of using Prony analysis to fit models to systems with characteristics often encountered in power systems. This understanding was then extended to develop general ``rules-of-thumb`` for using Prony analysis. The general characteristics were investigated by performing fits to data from known linear models under controlled conditions. The conditions studied include various mathematical solution techniques; different parent system configurations; and a large variety of underlying noise characteristics.

  20. Stochastic Dynamic Demand Inventory Models with Explicit Transportation Costs and Decisions 

    E-Print Network [OSTI]

    Zhang, Liqing

    2011-07-01

    Peters August 2011 Major Subject: Industrial Engineering iii ABSTRACT Stochastic Dynamic Demand Inventory Models with Explicit Transportation Costs and Decisions. (August 2011) Liqing Zhang, B.S.; M.S., Tsinghua University, P.R. China Chair... An Illustration of (Q,~s, ~S) Policy ( m = ? s1n?Qn C ? + 1 ) . . . . . . . . 52 5 Optimal Policies for Special Case . . . . . . . . . . . . . . . . . . . . 71 6 Influence of Parameter K . . . . . . . . . . . . . . . . . . . . . . . . 74 7 Influence...

  1. Optimal Control of Distributed Energy Resources using Model Predictive Control

    SciTech Connect (OSTI)

    Mayhorn, Ebony T.; Kalsi, Karanjit; Elizondo, Marcelo A.; Zhang, Wei; Lu, Shuai; Samaan, Nader A.; Butler-Purry, Karen

    2012-07-22

    In an isolated power system (rural microgrid), Distributed Energy Resources (DERs) such as renewable energy resources (wind, solar), energy storage and demand response can be used to complement fossil fueled generators. The uncertainty and variability due to high penetration of wind makes reliable system operations and controls challenging. In this paper, an optimal control strategy is proposed to coordinate energy storage and diesel generators to maximize wind penetration while maintaining system economics and normal operation. The problem is formulated as a multi-objective optimization problem with the goals of minimizing fuel costs and changes in power output of diesel generators, minimizing costs associated with low battery life of energy storage and maintaining system frequency at the nominal operating value. Two control modes are considered for controlling the energy storage to compensate either net load variability or wind variability. Model predictive control (MPC) is used to solve the aforementioned problem and the performance is compared to an open-loop look-ahead dispatch problem. Simulation studies using high and low wind profiles, as well as, different MPC prediction horizons demonstrate the efficacy of the closed-loop MPC in compensating for uncertainties in wind and demand.

  2. Dynamics of a multigroup epidemiological model with group ...

    E-Print Network [OSTI]

    Lamwah Chow

    2011-09-22

    spread across multiple countries and transmission between different subgroups in a ... Multigroup models have been used to study transmission dynamics of ...

  3. Optimization of the structural Gabor functions in a homogeneous velocity model

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Optimization of the structural Gabor functions in a homogeneous velocity model for a zero-o#11;set functions should be optimized, and the Gabor functions should form a frame. We present a simple attempt functions and the space{wavenumber lattice of their central points are optimized analytically

  4. Deep Learning Helicopter Dynamics Models Ali Punjani and Pieter Abbeel

    E-Print Network [OSTI]

    Abbeel, Pieter

    Deep Learning Helicopter Dynamics Models Ali Punjani and Pieter Abbeel Abstract-- We consider the problem of system identification of helicopter dynamics. Helicopters are complex systems, cou- pling rigid inspiration from recent results in Deep Learning to represent the helicopter dynamics with a Rectified Linear

  5. 20.18 Optimization Problems in Air Pollution Modeling Ivan Dimov, and Zahari Zlatev

    E-Print Network [OSTI]

    Dimov, Ivan

    20.18 Optimization Problems in Air Pollution Modeling Ivan Dimov, and Zahari Zlatev ABSTRACT. The appearance of optimization problems in the field of air pollution modeling and their importance arising in air pollution modeling will be considered. We shall present a review of some approaches

  6. Application of stochastic parameter optimization to the Sacramento Soil Moisture Accounting model

    E-Print Network [OSTI]

    Wagener, Thorsten

    parameter set and underlying posterior distribution within a single optimization run. In particular, weApplication of stochastic parameter optimization to the Sacramento Soil Moisture Accounting model Moisture Accounting model (SAC-SMA) model using historical data from the Leaf River in Mississippi

  7. Applying the Battery Ownership Model in Pursuit of Optimal Battery Use Strategies (Presentation)

    SciTech Connect (OSTI)

    Neubauer, J.; Ahmad, P.; Brooker, A.; Wood, E.; Smith, K.; Johnson, C.; Mendelsohn, M.

    2012-05-01

    This Annual Merit Review presentation describes the application of the Battery Ownership Model for strategies for optimal battery use in electric drive vehicles (PEVs, PHEVs, and BEVs).

  8. Optimal rotary control of the cylinder wake using POD Reduced Order Model

    E-Print Network [OSTI]

    Bergmann, Michel

    Optimal rotary control of the cylinder wake using POD Reduced Order Model Michel Bergmann, Laurent frequently in engineering computations) obtained by spatial discretization of the governing equations need

  9. Dynamic Modeling and Recipe Optimization of Polyether Polyol Processes

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    Center for Advanced Process Decision-making Department of Chemical Engineering Carnegie Mellon University Epoxides (ethylene oxide (EO), propylene oxide (PO)) OO OO Molecules containing active hydrogen atoms + YT a YT b ZT g(t) Stable solution needs f(x) = 0, when Reformulated system YT a x

  10. Time consistency and risk averse dynamic decision models ...

    E-Print Network [OSTI]

    2013-05-02

    sistent models as we provide practitioners with an intuitive economic inter- pretation for the ... ning and financial engineering problems. Based on ... consistency is shown to be one basic requirement to get suitable optimal de- cisions, in ...

  11. Dynamical Reduction Models with General Gaussian Noises

    E-Print Network [OSTI]

    Angelo Bassi; GianCarlo Ghirardi

    2002-01-27

    We consider the effect of replacing in stochastic differential equations leading to the dynamical collapse of the statevector, white noise stochastic processes with non white ones. We prove that such a modification can be consistently performed without altering the most interesting features of the previous models. One of the reasons to discuss this matter derives from the desire of being allowed to deal with physical stochastic fields, such as the gravitational one, which cannot give rise to white noises. From our point of view the most relevant motivation for the approach we propose here derives from the fact that in relativistic models the occurrence of white noises is the main responsible for the appearance of untractable divergences. Therefore, one can hope that resorting to non white noises one can overcome such a difficulty. We investigate stochastic equations with non white noises, we discuss their reduction properties and their physical implications. Our analysis has a precise interest not only for the above mentioned subject but also for the general study of dissipative systems and decoherence.

  12. Polymer Reaction Engineering Laboratory -University of Maryland at College Park Reactor Dynamics, Control, Optimization

    E-Print Network [OSTI]

    Choi, Kyu Yong

    of viscosity dependent heat transfer coefficient (K.J. Kim, K.Y. Choi and J.C. Alexander), Polym. Eng. Sci., 32 nonlinear steady state and transient behaviors. The topic of reactor dynamics has been the subject reactors and model-based control of polymerization reactors using extended Kalman filter. 1. Analysis

  13. Towards Dynamic Pricing-Based Collaborative Optimizations for Green Data Centers

    E-Print Network [OSTI]

    Plotkin, Joshua B.

    . Meanwhile, market penetration of intermittent renewable energy sources (e.g., wind and solar) is on the rise using real intermittent-energy-generation trace data. Modeling the dynamic price over this trace, we energy efficiency is therefore a shared problem between both electric utilities and data centers. Data

  14. From quantum to classical dynamics: Dynamic crossover in the relativistic $O(N)$ model

    E-Print Network [OSTI]

    Mesterházy, David; Tanizaki, Yuya

    2015-01-01

    We investigate the transition from quantum to classical dynamics in the relativistic $O(N)$ vector model using the nonperturbative functional renormalization group in the real-time formalism. In thermal equilibrium, the theory is characterized by two scales, the interaction range for coherent scattering of particles and the mean free path determined by the rate of incoherent collision with excitations in the thermal medium. Their competition determines the renormalization group flow and the effective dynamics of the model. Here we quantify the dynamic properties of the model in terms of the scale-dependent dynamic critical exponent $z$ for arbitrary temperatures and in $2 \\leq d \\leq 4$ spatial dimensions.

  15. A Dynamic Network Oligopoly Model Transportation Costs, Product Differentiation,

    E-Print Network [OSTI]

    Nagurney, Anna

    and Operations Management Isenberg School of Management University of Massachusetts Amherst, Massachusetts 01003A Dynamic Network Oligopoly Model with Transportation Costs, Product Differentiation, and Quality Network Oligopoly Model with Quality Competition #12;Acknowledgments This research was supported, in part

  16. Learning vehicular dynamics, with application to modeling helicopters

    E-Print Network [OSTI]

    Thrun, Sebastian

    Learning vehicular dynamics, with application to modeling helicopters Pieter Abbeel Computer Abstract We consider the problem of modeling a helicopter's dynamics based on state­action trajectories such as learned by CIFER (the industry standard in helicopter identification), and show that the linear

  17. Learning vehicular dynamics, with application to modeling helicopters

    E-Print Network [OSTI]

    Thrun, Sebastian

    Learning vehicular dynamics, with application to modeling helicopters Pieter Abbeel Computer Abstract We consider the problem of modeling a helicopter's dynamics based on state-action trajectories such as learned by CIFER (the industry standard in helicopter identification), and show that the linear

  18. Modeling microbial dynamics in heterogeneous environments: Growth on soil carbon sources

    SciTech Connect (OSTI)

    Resat, Haluk; Bailey, Vanessa L.; McCue, Lee Ann; Konopka, Allan

    2012-01-01

    We have developed a new hybrid model to study how microbial dynamics are affected by the heterogeneity in the physical structure of the environment. The modeling framework can represent porous media such as soil. The individual based biological model can explicitly simulate microbial diversity, and cell metabolism is regulated via optimal allocation of cellular resources to enzyme synthesis, control of growth rate by protein synthesis capacity, and shifts to dormancy. This model was developed to study how microbial community functioning is influenced by local environmental conditions and by the functional attributes of individual microbes. Different strategies for acquisition of carbon from polymeric cellulose were investigated. Bacteria that express membrane-associated hydrolase had different growth and survival dynamics in soil pores than bacteria that release extracellular hydrolases. The kinetic differences may suggest different functional roles for these two classes of microbes in cellulose utilization. Our model predicted an emergent behavior in which co-existence led to higher cellulose utilization efficiency and reduced stochasticity. Microbial community dynamics were simulated at two spatial scales: micro-pores that resemble 6-20 {micro}m size portions of the soil physical structure and in 111 {micro}m size soil aggregates with a random pore structure. Trends in dynamic properties were very similar at these two scales, implying that micro-scale studies can be useful approximations to aggregate scale studies when local effects on microbial dynamics are studied.

  19. Optimization and neural modelling of pulse combustors for drying applications

    SciTech Connect (OSTI)

    Zbicinski, I.; Smucerowicz, I.; Strumillo, C.; Kasznia, J.; Stawczyk, J.; Murlikiewicz, K. [Technical Univ. of Lodz (Poland). Faculty of Process and Environmental Engineering

    1999-03-01

    Results of investigations of a valved pulse combustor to choose optimal geometry, which covered measurements of the flow rates of air and fuel, pressure oscillations, including pressure amplitude and frequency and flue gas composition are presented in the paper. Experimental studies comparing the operation of the pulse combustor coupled with a drying chamber and working separately are described. It was found that coupling of the pulse combustor with a drying chamber had no significant effect on the pulse combustion process. Smoother runs of pressure oscillations in the combustion chamber, lower noise level and slightly higher NO{sub x} emission were observed. The velocity flow field inside the drying chamber was measured by LDA technique. Results confirmed a complex character of pulsating flow in the chamber. A large experimental data set obtained from measurements enabled developing a neural model of pulse combustion process. Artificial neural networks were trained to predict amplitudes and frequencies of pressure oscillations, temperatures in the combustion chamber and emission of toxic substances. An excellent mapping performance of the developed neural models was obtained. Due to complex character of the pulse combustion process, the application of artificial neural networks seems to be the best way to predict inlet parameters of drying agent produced by the pulse combustor.

  20. Optimal system size for complex dynamics in random neural networks near criticality

    SciTech Connect (OSTI)

    Wainrib, Gilles, E-mail: wainrib@math.univ-paris13.fr [Laboratoire Analyse Géométrie et Applications, Université Paris XIII, Villetaneuse (France)] [Laboratoire Analyse Géométrie et Applications, Université Paris XIII, Villetaneuse (France); García del Molino, Luis Carlos, E-mail: garciadelmolino@ijm.univ-paris-diderot.fr [Institute Jacques Monod, Université Paris VII, Paris (France)

    2013-12-15

    In this article, we consider a model of dynamical agents coupled through a random connectivity matrix, as introduced by Sompolinsky et al. [Phys. Rev. Lett. 61(3), 259–262 (1988)] in the context of random neural networks. When system size is infinite, it is known that increasing the disorder parameter induces a phase transition leading to chaotic dynamics. We observe and investigate here a novel phenomenon in the sub-critical regime for finite size systems: the probability of observing complex dynamics is maximal for an intermediate system size when the disorder is close enough to criticality. We give a more general explanation of this type of system size resonance in the framework of extreme values theory for eigenvalues of random matrices.

  1. Computational Fluid Dynamics (CFD) Modeling for High Rate Pulverized Coal Injection (PCI) into the Blast Furnace

    SciTech Connect (OSTI)

    Dr. Chenn Zhou

    2008-10-15

    Pulverized coal injection (PCI) into the blast furnace (BF) has been recognized as an effective way to decrease the coke and total energy consumption along with minimization of environmental impacts. However, increasing the amount of coal injected into the BF is currently limited by the lack of knowledge of some issues related to the process. It is therefore important to understand the complex physical and chemical phenomena in the PCI process. Due to the difficulty in attaining trus BF measurements, Computational fluid dynamics (CFD) modeling has been identified as a useful technology to provide such knowledge. CFD simulation is powerful for providing detailed information on flow properties and performing parametric studies for process design and optimization. In this project, comprehensive 3-D CFD models have been developed to simulate the PCI process under actual furnace conditions. These models provide raceway size and flow property distributions. The results have provided guidance for optimizing the PCI process.

  2. Gas Network Optimization: A comparison of Piecewise Linear Models

    E-Print Network [OSTI]

    2014-06-22

    Gas network optimization manages the gas transport by minimizing operating costs and .... This problem represents the transportation process of natural gas. 79.

  3. Optimal consumption in a growth model with the Cobb-Douglas production function

    E-Print Network [OSTI]

    Optimal consumption in a growth model with the Cobb-Douglas production function Hiroaki Morimoto Management, The Chinese University of Hong Kong, Shatin, Hong Kong Abstract An optimal consumption problem is studied in a growth model for the Cobb-Douglas production function in a finite horizon. The problem

  4. Parameter optimization for the Gaussian model of protein foldingq Albert Erkipa

    E-Print Network [OSTI]

    Seok, Chaok

    of protein folding and ligand docking are large and complex. Few systematic methods have yet been developed apply this parameter optimization method to the recently developed Gaussian model of protein folding Science Ltd. All rights reserved. Keywords: Gaussian model; Protein folding; Parameter optimization 1

  5. Mooring Line Modelling and Design Optimization of Floating Offshore Wind Turbines

    E-Print Network [OSTI]

    Victoria, University of

    Mooring Line Modelling and Design Optimization of Floating Offshore Wind Turbines by Matthew Thomas Mooring Line Modelling and Design Optimization of Floating Offshore Wind Turbines by Matthew Thomas Jair was coupled to the floating wind turbine simulator FAST. The results of the comparison study indicate the need

  6. Finite Element Solution of Optimal Control Problems Arising in Semiconductor Modeling

    E-Print Network [OSTI]

    Siefert, Chris

    - timization problem, especially for highly heterogeneous materials with large jumps in material properties. 1Finite Element Solution of Optimal Control Problems Arising in Semiconductor Modeling Pavel Bochev, and inverse problems arising in the modeling of semiconductor devices lead to optimization problems

  7. Optimizing a dynamical decoupling protocol for solid-state electronic spin ensembles in diamond

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Farfurnik, D.; Jarmola, A.; Pham, L. M.; Wang, Z. H.; Dobrovitski, V. V.; Walsworth, R. L.; Budker, D.; Bar-Gill, N.

    2015-08-24

    We demonstrate significant improvements of the spin coherence time of a dense ensemble of nitrogen-vacancy (NV) centers in diamond through optimized dynamical decoupling (DD). Cooling the sample down to 77 K suppresses longitudinal spin relaxation T1 effects and DD microwave pulses are used to increase the transverse coherence time T2 from ~0.7ms up to ~30ms. Furthermore, we extend previous work of single-axis (Carr-Purcell-Meiboom-Gill) DD towards the preservation of arbitrary spin states. Following a theoretical and experimental characterization of pulse and detuning errors, we compare the performance of various DD protocols. We also identify that the optimal control scheme for preservingmore »an arbitrary spin state is a recursive protocol, the concatenated version of the XY8 pulse sequence. The improved spin coherence might have an immediate impact on improvements of the sensitivities of ac magnetometry. Moreover, the protocol can be used on denser diamond samples to increase coherence times up to NV-NV interaction time scales, a major step towards the creation of quantum collective NV spin states.« less

  8. Dynamic Modeling in Solid-Oxide Fuel Cells Controller Design

    SciTech Connect (OSTI)

    Lu, Ning; Li, Qinghe; Sun, Xin; Khaleel, Mohammad A.

    2007-06-28

    In this paper, a dynamic model of the solid-oxide fuel cell (SOFC) power unit is developed for the purpose of designing a controller to regulate fuel flow rate, fuel temperature, air flow rate, and air temperature to maintain the SOFC stack temperature, fuel utilization rate, and voltage within operation limits. A lumped model is used to consider the thermal dynamics and the electro-chemial dynamics inside an SOFC power unit. The fluid dynamics at the fuel and air inlets are considered by using the in-flow ramp-rates.

  9. Developing a Dynamic Pharmacophore Model for HIV-1 Integrase

    SciTech Connect (OSTI)

    Carlson, Heather A.; Masukawa, Keven M.; Rubins, Kathleen; Bushman, Frederic; Jorgensen, William L.; Lins, Roberto; Briggs, James; Mccammon, Andy

    2000-05-11

    We present the first receptor-based pharmacophore model for HIV-1 integrase. The development of ''dynamic'' pharmacophore models is a new method that accounts for the inherent flexibility of the active site and aims to reduce the entropic penalties associated with binding a ligand. Furthermore, this new drug discovery method overcomes the limitation of an incomplete crystal structure of the target protein. A molecular dynamics (MD) simulation describes the flexibility of the uncomplexed protein. Many conformational models of the protein are saved from the MD simulations and used in a series of multi-unit search for interacting conformers (MUSIC) simulations. MUSIC is a multiple-copy minimization method, available in the BOSS program; it is used to determine binding regions for probe molecules containing functional groups that complement the active site. All protein conformations from the MD are overlaid, and conserved binding regions for the probe molecules are identified. Those conserved binding regions define the dynamic pharmacophore model. Here, the dynamic model is compared to known inhibitors of the integrase as well as a three-point, ligand-based pharmacophore model from the literature. Also, a ''static'' pharmacophore model was determined in the standard fashion, using a single crystal structure. Inhibitors thought to bind in the active site of HIV-1 integrase fit the dynamic model but not the static model. Finally, we have identified a set of compounds from the Available Chemicals Directory that fit the dynamic pharmacophore model, and experimental testing of the compounds has confirmed several new inhibitors.

  10. Optimal SCR Control Using Data-Driven Models

    SciTech Connect (OSTI)

    Stevens, Andrew J.; Sun, Yannan; Lian, Jianming; Devarakonda, Maruthi N.; Parker, Gordon

    2013-04-16

    We present an optimal control solution for the urea injection for a heavy-duty diesel (HDD) selective catalytic reduction (SCR). The approach taken here is useful beyond SCR and could be applied to any system where a control strategy is desired and input-output data is available. For example, the strategy could also be used for the diesel oxidation catalyst (DOC) system. In this paper, we identify and validate a one-step ahead Kalman state-space estimator for downstream NOx using the bench reactor data of an SCR core sample. The test data was acquired using a 2010 Cummins 6.7L ISB production engine with a 2010 Cummins production aftertreatment system. We used a surrogate HDD federal test procedure (FTP), developed at Michigan Technological University (MTU), which simulates the representative transients of the standard FTP cycle, but has less engine speed/load points. The identified state-space model is then used to develop a tunable cost function that simultaneously minimizes NOx emissions and urea usage. The cost function is quadratic and univariate, thus the minimum can be computed analytically. We show the performance of the closed-loop controller in using a reduced-order discrete SCR simulator developed at MTU. Our experiments with the surrogate HDD-FTP data show that the strategy developed in this paper can be used to identify performance bounds for urea dose controllers.

  11. Finding Benefits by Modeling and Optimizing Steam and Power Systems 

    E-Print Network [OSTI]

    Harper, C.; Nelson, D. A.

    2008-01-01

    case studies which can be used to optimize production of these products on our industrial gas pipelines. The program is used for both day-to-day site optimization, outage forecasting, and long-term site planning. In this presentation, we will discuss...

  12. Continuously Optimized Reliable Energy (CORE) Microgrid: Models & Tools (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-07-01

    This brochure describes Continuously Optimized Reliable Energy (CORE), a trademarked process NREL employs to produce conceptual microgrid designs. This systems-based process enables designs to be optimized for economic value, energy surety, and sustainability. Capabilities NREL offers in support of microgrid design are explained.

  13. Planning for multiple mobile robots in dynamic environ-ments involves determining the optimal path each robot

    E-Print Network [OSTI]

    Stentz, Tony

    Abstract Planning for multiple mobile robots in dynamic environ- ments involves determining the optimal path each robot should follow to accomplish the goals of the mission, given the current knowledge reassign robots to goals in order to continually minimize the time to complete the mission. In this paper

  14. Dynamics, Optimization and Control of a Fuel Cell Based Combined Heat Power (CHP) System for Shipboard Applications

    E-Print Network [OSTI]

    Stefanopoulou, Anna

    Dynamics, Optimization and Control of a Fuel Cell Based Combined Heat Power (CHP) System, a natural gas fuel processor system (FPS), a proton exchange membrane fuel cell (PEM-FC) and a catalytic) systems based on fuel cells and fuel processing technologies have great potential for future shipboard

  15. Submitted to 43rd AIAA Fluid Dynamics Conference and Exhibit, 24-27 June 2013, San Diego, California Multi-Objective Design Optimization of a Transonic

    E-Print Network [OSTI]

    Liu, Feng

    -objective design optimization of a transonic compressor rotor blade row. The adjoint method requires about twice single-objective design optimizations. Firstly a set of blades with different gains of total pressure Computational Fluid Dynamics (CFD), many research papers on design optimization of com- pressor blades have been

  16. Modeling dilute sediment suspension using large-eddy simulation with a dynamic mixed model

    E-Print Network [OSTI]

    Fringer, Oliver B.

    Modeling dilute sediment suspension using large-eddy simulation with a dynamic mixed model Yi Transport of suspended sediment in high Reynolds number channel flows Re=O 600 000 is simulated using large-eddy simulation along with a dynamic-mixed model DMM . Because the modeled sediment concentration is low

  17. Generic solar photovoltaic system dynamic simulation model specification.

    SciTech Connect (OSTI)

    Ellis, Abraham; Behnke, Michael Robert; Elliott, Ryan Thomas

    2013-10-01

    This document is intended to serve as a specification for generic solar photovoltaic (PV) system positive-sequence dynamic models to be implemented by software developers and approved by the WECC MVWG for use in bulk system dynamic simulations in accordance with NERC MOD standards. Two specific dynamic models are included in the scope of this document. The first, a Central Station PV System model, is intended to capture the most important dynamic characteristics of large scale (> 10 MW) PV systems with a central Point of Interconnection (POI) at the transmission level. The second, a Distributed PV System model, is intended to represent an aggregation of smaller, distribution-connected systems that comprise a portion of a composite load that might be modeled at a transmission load bus.

  18. Dynamic wind turbine models in power system simulation tool

    E-Print Network [OSTI]

    Dynamic wind turbine models in power system simulation tool DIgSILENT Anca D. Hansen, Florin Iov Iov, Poul Sørensen, Nicolaos Cutululis, Clemens Jauch, Frede Blaabjerg Title: Dynamic wind turbine system simulation tool PowerFactory DIgSILENT for different wind turbine concepts. It is the second

  19. Novel Dynamical Modeling for Series-Parallel Resonant Converter

    E-Print Network [OSTI]

    Noé, Reinhold

    and voltage waveforms in the resonant tank are assumed to be sinusoidal. Using this approach steady enables accurate calculation of steady-state characteristics under all (light to heavy) load conditions. For studying the dynamical behavior of the SPRC and for control design dynamical modeling techniques

  20. Fibre Based Modeling of Wood Dynamics and Fracture

    E-Print Network [OSTI]

    Bridson, Robert

    Fibre Based Modeling of Wood Dynamics and Fracture by Sean Meiji Sutherland B.Sc., The University for the simulation of the dynamics and fracturing char- acteristics of wood, specifically its anisotropic behaviour bundles of fibres. Additionally, we describe the conditions under which fracture occurs in the material

  1. Stochastic modeling of lift and drag dynamics under turbulent conditions

    E-Print Network [OSTI]

    Peinke, Joachim

    Matthias Wächter Joachim Peinke ForWind - Center for Wind Energy Research University of Oldenburg, Germany measurement. The model is being developed with the aim to integrate it into a general wind energy converter dynamics, drag dynamics. 1 Introduction Wind energy converters (WECs) are permanently exposed to turbulent

  2. Comparing Families of Dynamic Causal Models Will D. Penny1

    E-Print Network [OSTI]

    Daunizeau, Jean

    Comparing Families of Dynamic Causal Models Will D. Penny1 *, Klaas E. Stephan1,2 , Jean Daunizeau1: Penny WD, Stephan KE, Daunizeau J, Rosa MJ, Friston KJ, et al. (2010) Comparing Families of Dynamic, 2010; Published March 12, 2010 Copyright: Ã? 2010 Penny et al. This is an open-access article

  3. Aging of asymmetric dynamics on the random energy model

    E-Print Network [OSTI]

    Pierre Mathieu; Jean-Christophe Mourrat

    2013-03-20

    We show aging of Glauber-type dynamics on the random energy model, in the sense that we obtain the scaling limits of the clock process and of the age process. The latter encodes the Gibbs weight of the configuration occupied by the dynamics. Both limits are expressed in terms of stable subordinators.

  4. Dynamic Simulation Model of a Consumer Foods Production Process !

    E-Print Network [OSTI]

    Sun, Yu

    schedule based on product list The SIMUL8 Component 1. Over 200 lines of simula0on code 2. ReadsDynamic Simulation Model of a Consumer Foods Production Process ! Goals · Create a dynamic simula0 Created par0ally automated Excel files to go handin hand with simula0on o Contains all SKUs and meat

  5. Dynamic Modelling for Control of Fuel Cells Federico Zenith

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Dynamic Modelling for Control of Fuel Cells Federico Zenith Sigurd Skogestad Department of Chemical Engineering Norwegian University of Science and Technology ( ntnu) Trondheim Abstract Fuel-cell dynamics have been investigated with a variable-resistance board applied to a high temperature polymer fuel cell

  6. Modeling and Optimization of a Bioethanol Production Facility 

    E-Print Network [OSTI]

    Gabriel, Kerron Jude

    2011-10-21

    The primary objective of this work is to identify the optimal bioethanol production plant capacity and configuration based on currently available technology for all the processing sections involved. To effect this study, a systematic method...

  7. Kinetic modeling and automated optimization in microreactor systems

    E-Print Network [OSTI]

    Moore, Jason Stuart

    2013-01-01

    The optimization, kinetic investigation, or scale-up of a reaction often requires significant time and materials. Silicon microreactor systems have been shown advantageous for studying chemical reactions due to their small ...

  8. OPTIMAL METABOLIC REGULATION USING A CONSTRAINT-BASED MODEL

    E-Print Network [OSTI]

    Segrè, Daniel

    role in the maintenance of metabolic homeostasis, and in the capacity of living systems to undergo: metabolic regulation; flux balance analysis; enzyme kinetics; metabolism; optimality; logistic map; chaos 1

  9. Modeling, Optimization and Economic Evaluation of Residual Biomass Gasification 

    E-Print Network [OSTI]

    Georgeson, Adam

    2012-02-14

    and product options are available for gasification along with combinations thereof. The objective of this work is to create a systematic method for optimizing the design of a residual biomass gasification unit. In detail, this work involves development...

  10. Optimal reservoir management using adaptive reduced-order models

    E-Print Network [OSTI]

    Alghareeb, Zeid M

    2015-01-01

    Reservoir management and decision-making is often cast as an optimization problem where we seek to maximize the field's potential recovery while minimizing associated operational costs. Two reservoir management aspects are ...

  11. Oneida Tribe of Indians of Wisconsin Energy Optimization Model

    SciTech Connect (OSTI)

    Troge, Michael

    2014-12-30

    Oneida Nation is located in Northeast Wisconsin. The reservation is approximately 96 square miles (8 miles x 12 miles), or 65,000 acres. The greater Green Bay area is east and adjacent to the reservation. A county line roughly splits the reservation in half; the west half is in Outagamie County and the east half is in Brown County. Land use is predominantly agriculture on the west 2/3 and suburban on the east 1/3 of the reservation. Nearly 5,000 tribally enrolled members live in the reservation with a total population of about 21,000. Tribal ownership is scattered across the reservation and is about 23,000 acres. Currently, the Oneida Tribe of Indians of Wisconsin (OTIW) community members and facilities receive the vast majority of electrical and natural gas services from two of the largest investor-owned utilities in the state, WE Energies and Wisconsin Public Service. All urban and suburban buildings have access to natural gas. About 15% of the population and five Tribal facilities are in rural locations and therefore use propane as a primary heating fuel. Wood and oil are also used as primary or supplemental heat sources for a small percent of the population. Very few renewable energy systems, used to generate electricity and heat, have been installed on the Oneida Reservation. This project was an effort to develop a reasonable renewable energy portfolio that will help Oneida to provide a leadership role in developing a clean energy economy. The Energy Optimization Model (EOM) is an exploration of energy opportunities available to the Tribe and it is intended to provide a decision framework to allow the Tribe to make the wisest choices in energy investment with an organizational desire to establish a renewable portfolio standard (RPS).

  12. REGULAR ARTICLE A Simple Dynamic Model of Respiratory Pump

    E-Print Network [OSTI]

    Fontecave-Jallon, Julie

    REGULAR ARTICLE A Simple Dynamic Model of Respiratory Pump Pascale Calabrese · Pierre Baconnier the relative motion of rib cage and abdomen during quiet breathing. Keywords Respiratory pump model Á. Hillman and Finucane (1987) have produced a simple model of the respiratory pump that ``appears

  13. A Diffusion Model in Population Genetics with Mutation and Dynamic

    E-Print Network [OSTI]

    O'Leary, Michael

    A Diffusion Model in Population Genetics with Mutation and Dynamic Fitness Mike O'Leary Department of Mathematics Towson University May 24, 2008 Mike O'Leary (Towson University) A Diffusion Model in Genetics May Miller, Georgetown University Mike O'Leary (Towson University) A Diffusion Model in Genetics May 24, 2008

  14. COMPUTATIONAL FLUID DYNAMICS MODELING OF SOLID OXIDE FUEL CELLS

    E-Print Network [OSTI]

    COMPUTATIONAL FLUID DYNAMICS MODELING OF SOLID OXIDE FUEL CELLS Ugur Pasaogullari and Chao-dimensional model has been developed to simulate solid oxide fuel cells (SOFC). The model fully couples current density operation. INTRODUCTION Solid oxide fuel cells (SOFC) are among possible candidates

  15. A Compositional and Dynamic Model for Face Aging

    E-Print Network [OSTI]

    Zhu, Song Chun

    A Compositional and Dynamic Model for Face Aging Jinli Suo, Song-Chun Zhu, Shiguang Shan, Member model for face aging. The compositional model represents faces in each age group by a hierarchical And.) crucial for age perception and Or nodes represent large diversity of faces by alternative selections

  16. High-throughput generation, optimization and analysis of genome-scale metabolic models.

    SciTech Connect (OSTI)

    Henry, C. S.; DeJongh, M.; Best, A. A.; Frybarger, P. M.; Linsay, B.; Stevens, R. L.

    2010-09-01

    Genome-scale metabolic models have proven to be valuable for predicting organism phenotypes from genotypes. Yet efforts to develop new models are failing to keep pace with genome sequencing. To address this problem, we introduce the Model SEED, a web-based resource for high-throughput generation, optimization and analysis of genome-scale metabolic models. The Model SEED integrates existing methods and introduces techniques to automate nearly every step of this process, taking {approx}48 h to reconstruct a metabolic model from an assembled genome sequence. We apply this resource to generate 130 genome-scale metabolic models representing a taxonomically diverse set of bacteria. Twenty-two of the models were validated against available gene essentiality and Biolog data, with the average model accuracy determined to be 66% before optimization and 87% after optimization.

  17. A Dynamic Island Model for Adaptive Operator Selection Caner Candan

    E-Print Network [OSTI]

    Goëffon, Adrien

    A Dynamic Island Model for Adaptive Operator Selection Caner Candan LERIA - University of Angers Angers, France caner.candan@univ-angers.fr Adrien Goëffon LERIA - University of Angers Angers, France

  18. Applications of axial and radial compressor dynamic system modeling

    E-Print Network [OSTI]

    Spakovszky, Zoltán S. (Zoltán Sándor), 1972-

    2001-01-01

    The presented work is a compilation of four different projects related to axial and centrifugal compression systems. The projects are related by the underlying dynamic system modeling approach that is common in all of them. ...

  19. Human Growth and Body Weight Dynamics: An Integrative Systems Model

    E-Print Network [OSTI]

    Rahmandad, Hazhir

    Quantifying human weight and height dynamics due to growth, aging, and energy balance can inform clinical practice and policy analysis. This paper presents the first mechanism-based model spanning full individual life and ...

  20. Modeling and control of undesirable dynamics in atomic force microscopes

    E-Print Network [OSTI]

    El Rifai, Osamah M

    2002-01-01

    The phenomenal resolution and versatility of the atomic force microscope (AFM), has made it a widely-used instrument in nanotechnology. In this thesis, a detailed model of AFM dynamics has been developed. It includes a new ...

  1. Model reduction for nonlinear dynamical systems with parametric uncertainties

    E-Print Network [OSTI]

    Zhou, Yuxiang Beckett

    2012-01-01

    Nonlinear dynamical systems are known to be sensitive to input parameters. In this thesis, we apply model order reduction to an important class of such systems -- one which exhibits limit cycle oscillations (LCOs) and ...

  2. Off-line calibration of Dynamic Traffic Assignment models

    E-Print Network [OSTI]

    Balakrishna, Ramachandran, 1978-

    2006-01-01

    Advances in Intelligent Transportation Systems (ITS) have resulted in the deployment of surveillance systems that automatically collect and store extensive network-wide traffic data. Dynamic Traffic Assignment (DTA) models ...

  3. Transmission Dynamics of an Influenza Model with Age of Infection ...

    E-Print Network [OSTI]

    2010-07-20

    J Dyn Diff Equat. DOI 10.1007/s10884-010-9178-x. Transmission Dynamics of an Influenza Model with Age of Infection and Antiviral Treatment. Zhipeng Qiu ...

  4. Multi-resolution modeling of the dynamic loading of metal matrix...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Multi-resolution modeling of the dynamic loading of metal matrix composites. Citation Details In-Document Search Title: Multi-resolution modeling of the dynamic...

  5. Developing Generic Dynamic Models for the 2030 Eastern Interconnection Grid

    SciTech Connect (OSTI)

    Kou, Gefei; Hadley, Stanton W; Markham, Penn N; Liu, Yilu

    2013-12-01

    The Eastern Interconnection Planning Collaborative (EIPC) has built three major power flow cases for the 2030 Eastern Interconnection (EI) based on various levels of energy/environmental policy conditions, technology advances, and load growth. Using the power flow cases, this report documents the process of developing the generic 2030 dynamic models using typical dynamic parameters. The constructed model was validated indirectly using the synchronized phasor measurements by removing the wind generation temporarily.

  6. Jamming transitions in force-based models for pedestrian dynamics

    E-Print Network [OSTI]

    Chraibi, Mohcine; Tordeux, Antoine; Nishinari, Katsuhiro; Schadschneider, Andreas; Seyfried, Armin

    2015-01-01

    Force-based models describe pedestrian dynamics in analogy to classical mechanics by a system of second order ordinary differential equations. By investigating the linear stability of two main classes of forces, parameter regions with unstable homogeneous states are identified. In this unstable regime it is then checked whether phase transitions or stop-and-go waves occur. Results based on numerical simulations show, however, that the investigated models lead to unrealistic behavior in form of backwards moving pedestrians and overlapping. This is one reason why stop-and-go waves have not been observed in these models. The unrealistic behavior is not related to the numerical treatment of the dynamic equations but rather indicates an intrinsic problem of this model class. Identifying the underlying generic problems gives indications how to define models that do not show such unrealistic behavior. As an example we introduce a new force-based model which produces realistic jam dynamics without the appearance of u...

  7. Dynamic modeling of a single-stage downward firing, entrained flow gasifier

    SciTech Connect (OSTI)

    Kasule, J., Turton, R., Bhattacharyya, D., Zitney, S.

    2012-01-01

    The gasifier is the heart of the integrated gasification combined cycle (IGCC), a technology that has emerged as an attractive alternative to conventional coal-fired power plant technology due to its higher efficiency and cleaner environmental performance especially with the option of CO{sub 2} capture and sequestration. Understanding the optimal performance of the gasifier is therefore paramount for the efficient operation of IGCC power plants. Numerous gasifier models of varying complexity have been developed to study the various aspects of gasifier performance. These range from simple one-dimensional (1D) process-type models to rigorous higher order 2-3D models based on computational fluid dynamics (CFD). Whereas high-fidelity CFD models can accurately predict most key aspects of gasifier performance, they are computationally expensive and typically take hours to days to execute on high-performance computers. Therefore, faster 1D partial differential equation (PDE)-based models are required for use in dynamic simulation studies, control system analysis, and training applications. A number of 1D gasifier models can be found in the literature, but most are steady-state models that have limited application in the practical operation of the gasifier. As a result, 1D PDE-based dynamic models are needed to further study and predict gasifier performance under a wide variety of process conditions and disturbances. In the current study, a 1D transient model of a single-stage downward-fired GE/Texaco-type entrained-flow gasifier has been developed. The model comprises mass, momentum and energy balances for the gas and solid phases. The model considers the initial gasification processes of water evaporation and coal devolatilization. In addition, the key heterogeneous and homogeneous chemical reactions have been modeled. The resulting time-dependent PDE model is solved using the well-known method of lines approach in Aspen Custom Modeler®, whereby the PDEs in the spatial domain are discretized and the resulting differential algebraic equations (DAEs) are then integrated over time using a dynamic integrator. The dynamic response results of the gasifier performance parameters to certain disturbances commonly encountered during practical operation are presented. These disturbances include ramp and step changes to input variables such as coal flow rate, oxygen-to-coal ratio and water-to-coal ratio among others. Comparison of model predictions to available dynamic data will also be discussed.

  8. Sensitivity Analysis of Optimal Operation of an Activated Sludge Process Model for Economic Controlled Variable Selection

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Sensitivity Analysis of Optimal Operation of an Activated Sludge Process Model for Economic operation conducted on an activated sludge process model based on the test-bed benchmark simulation model no. 1 (BSM1) and the activated sludge model no. 1 (ASM1). The objective is to search for a control

  9. Dynamic reactor modeling with applications to SPR and ZEDNA.

    SciTech Connect (OSTI)

    Suo-Anttila, Ahti Jorma

    2011-12-01

    A dynamic reactor model has been developed for pulse-type reactor applications. The model predicts reactor power, axial and radial fuel expansion, prompt and delayed neutron population, and prompt and delayed gamma population. All model predictions are made as a function of time. The model includes the reactivity effect of fuel expansion on a dynamic timescale as a feedback mechanism for reactor power. All inputs to the model are calculated from first principles, either directly by solving systems of equations, or indirectly from Monte Carlo N-Particle Transport Code (MCNP) derived results. The model does not include any empirical parameters that can be adjusted to match experimental data. Comparisons of model predictions to actual Sandia Pulse Reactor SPR-III pulses show very good agreement for a full range of pulse magnitudes. The model is also applied to Z-pinch externally driven neutron assembly (ZEDNA) type reactor designs to model both normal and off-normal ZEDNA operations.

  10. Power system analysis project Modeling and Sizing optimization of Stand-alone

    E-Print Network [OSTI]

    Lavaei, Javad

    Power system analysis project Modeling and Sizing optimization of Stand-alone photovoltaic/wind to explore a new way to do the site matching of wind turbine by introducing the design parameters: cut-in, cut-out wind speed and rated power, into the optimization based on the real load of the site and write

  11. Change Management in Enterprise IT Systems: Process Modeling and Capacity-optimal Scheduling

    E-Print Network [OSTI]

    Sarkar, Saswati

    Change Management in Enterprise IT Systems: Process Modeling and Capacity-optimal Scheduling of the optimal fluid scheduling policy, which is well suited for application to a real change management system management ­ or handling of problem diagnosis and root cause analysis, and (ii) Change management ­ or timely

  12. A Network Modeling Approach Optimization of Internet-Based Advertising Strategies and Pricing

    E-Print Network [OSTI]

    Nagurney, Anna

    A Network Modeling Approach for the Optimization of Internet-Based Advertising Strategies and evaluation of optimal Internet mar- keting strategies when a firm is advertising on multiple websites examples are constructed that demonstrate two paradoxes: (1). that advertising on more websites may reduce

  13. An Enterprise Decision Model for Optimal Vehicle Design and Technology Valuation

    E-Print Network [OSTI]

    Papalambros, Panos

    engineering simulation to provide a preliminary understanding of the technology's market and design potentialAn Enterprise Decision Model for Optimal Vehicle Design and Technology Valuation by Adam B. Cooper for Optimal Vehicle Design and Technology Valuation by Adam B. Cooper Chair: Panos Y. Papalambros Design

  14. Global optimization by coupled local minimizers and its application to FE model updating

    E-Print Network [OSTI]

    -3001 Heverlee, Belgium Received 2 August 2002; accepted 3 July 2003 Abstract Coupled local minimizersGlobal optimization by coupled local minimizers and its application to FE model updating Anne (CLM) is a new method applicable to global optimization of functions with multiple local minima. In CLM

  15. Modeling Zero Energy Building: technical and economical optimization Maria Ferrara1-2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Modeling Zero Energy Building: technical and economical optimization Maria Ferrara1-2 , Joseph by the recast of Energy Performance of Buildings. The aim of this work is to provide a useful method to deal combines the use of TRNSYS, building energy simulation program, with GenOpt, Generic Optimization program

  16. Mesoscale modeling of phase transition dynamics of thermoresponsive polymers

    E-Print Network [OSTI]

    Li, Zhen; Li, Xuejin; Karniadakis, George Em

    2015-01-01

    We present a non-isothermal mesoscopic model for investigation of the phase transition dynamics of thermoresponsive polymers. Since this model conserves energy in the simulations, it is able to correctly capture not only the transient behavior of polymer precipitation from solvent, but also the energy variation associated with the phase transition process. Simulations provide dynamic details of the thermally induced phase transition and confirm two different mechanisms dominating the phase transition dynamics. A shift of endothermic peak with concentration is observed and the underlying mechanism is explored.

  17. Optimal threshold policies in a workload model with a variable number of service phases per job \\Lambda

    E-Print Network [OSTI]

    Brouns, Gido

    models, admission and termination control, optimal threshold policies, Markov decision processes. 1 systems. The basic principle of performance optimization is the question of how to control some type of models for the optimal control of queueing systems. Emphasis is laid on models based on Markov decision

  18. A stochastic evolutionary model for capturing human dynamics

    E-Print Network [OSTI]

    Fenner, Trevor; Loizou, George

    2015-01-01

    The recent interest in human dynamics has led researchers to investigate the stochastic processes that explain human behaviour in various contexts. Here we propose a generative model to capture the dynamics of survival analysis, traditionally employed in clinical trials and reliability analysis in engineering. We derive a general solution for the model in the form of a product, and then a continuous approximation to the solution via the renewal equation describing age-structured population dynamics. This enables us to model a wide rage of survival distributions, according to the choice of the mortality distribution. We provide empirical evidence for the validity of the model from a longitudinal data set of popular search engine queries over 114 months, showing that the survival function of these queries is closely matched by the solution for our model with power-law mortality.

  19. Using Evolution Strategy with Meta-models for Well Placement Optimization

    E-Print Network [OSTI]

    Bouzarkouna, Zyed; Auger, Anne

    2010-01-01

    Optimum implementation of non-conventional wells allows us to increase considerably hydrocarbon recovery. By considering the high drilling cost and the potential improvement in well productivity, well placement decision is an important issue in field development. Considering complex reservoir geology and high reservoir heterogeneities, stochastic optimization methods are the most suitable approaches for optimum well placement. This paper proposes an optimization methodology to determine optimal well location and trajectory based upon the Covariance Matrix Adaptation - Evolution Strategy (CMA-ES) which is a variant of Evolution Strategies recognized as one of the most powerful derivative-free optimizers for continuous optimization. To improve the optimization procedure, two new techniques are investigated: (1). Adaptive penalization with rejection is developed to handle well placement constraints. (2). A meta-model, based on locally weighted regression, is incorporated into CMA-ES using an approximate ranking ...

  20. Structure formation: Models, Dynamics and Status

    E-Print Network [OSTI]

    T. Padmanabhan

    1995-08-25

    The constraints on the models for the structure formation arising from various cosmological observations at different length scales are reviewed. The status of different models for structure formation is examined critically in the light of these observations.

  1. Modeling emotion dynamics in intelligent agents 

    E-Print Network [OSTI]

    Seif El-Nasr, Magy

    1998-01-01

    Emotions were shown to have a leading role in the human decision-making process, and thus they play an important role in human intelligence. Intelligent agents' research produced many models of emotional agents. However, most of these models focused...

  2. NOVEL APROACH TO PROCESS SYNTHESIS BASED ON DYNAMIC OPTIMIZATION AND EXPLOITION OF PROCESS

    E-Print Network [OSTI]

    Van den Hof, Paul

    is industrially relevant gas phase catalytic reaction ­ methane steam reforming accompanied with water gas shift, oscillatory baffled, helix, catalytic membrane) and ways of operation (optimal reactant feeding and optimal

  3. An optimization model for strategic supply chain design under stochastic capacity disruptions 

    E-Print Network [OSTI]

    Luna Coronado, Jaime

    2009-05-15

    .6. Numerical Example ...................................................................................... 54 6. OPTIMIZATION PROCEDURE ....................................................................... 60 6.1. Sample Average Approximation (SAA... ................................................................................ 66 7. IMPLEMENTATION AND NUMERICAL EXAMPLES????? ???.. 70 7.1. Model Implementation ................................................................................. 71 7.2. Numerical Examples...

  4. Design optimization and analysis of coated particle fuel using advanced fuel performance modeling techniques

    E-Print Network [OSTI]

    Soontrapa, Chaiyod

    2005-01-01

    Modifying material properties provides another approach to optimize coated particle fuel used in pebble bed reactors. In this study, the MIT fuel performance model (TIMCOAT) was applied after benchmarking against the ...

  5. Sparse Models and Methods for Optimal Instruments with an Application to Eminent Domain

    E-Print Network [OSTI]

    Belloni, Alexandre

    2011-07-12

    We develop results for the use of LASSO and Post-LASSO methods to form first-stage predictions and estimate optimal instruments in linear instrumental variables (IV) models with many instruments, p, that apply even when p ...

  6. Longitudinal Data Analysis Using Multilevel Linear Modeling (MLM): Fitting an Optimal Variance-Covariance Structure 

    E-Print Network [OSTI]

    Lee, Yuan-Hsuan

    2011-10-21

    This dissertation focuses on issues related to fitting an optimal variance-covariance structure in multilevel linear modeling framework with two Monte Carlo simulation studies. In the first study, the author evaluated the ...

  7. New methodologies for top-down statistical modeling and optimization of integrated circuits 

    E-Print Network [OSTI]

    Alexander, Daniel D.

    1996-01-01

    New methodologies intended to facilitate system level design and optimization are developed. Specifically, these methodologies allow: (1) development of system level models for the purpose of gathering statistical data on the performance of large...

  8. Geometric modeling and optimization in 3D solar cells : implementation and algorithms

    E-Print Network [OSTI]

    Wan, Jin Hao, M. Eng. Massachusetts Institute of Technology

    2014-01-01

    Conversion of solar energy in three-dimensional (3D) devices has been essentially untapped. In this thesis, I design and implement a C++ program that models and optimizes a 3D solar cell ensemble embedded in a given ...

  9. Design of penalty functions for optimal control of linear dynamical systems under state and input constraints

    E-Print Network [OSTI]

    optimization problem. In penalty function methods, an augmented performance index is introduced by adding to the original cost of the optimal control problem, so-called penalty functions that have some diverging performance index is optimized, in the absence of constraints, yielding a biased estimate of the solution

  10. Optimal Control for a System Modelling Tumor Anti-Angiogenesis

    E-Print Network [OSTI]

    Ledzewicz, Urszula

    inhibitors given. For both mod- els a full synthesis of optimal solutions is presented and the differences of chemotherapy in cancer treatments is drug resistance. Different from normal cells, cancer cells are geneti- cally highly unstable and thus quite diversified in their structure. As a consequence, some cancer cells

  11. ADVANCES IN MATHEMATICAL PROGRAMMING MODELS FOR ENTERPRISE-WIDE OPTIMIZATION

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    The chemical industry is a major component of the US economy, converting raw materials such as oil, natural gas, the US chemical industry is responsible for 10 percent of US merchandise exports, totaling US$145 billion Pittsburgh, PA 15213 Abstract Enterprise-wide optimization (EWO) is an area that lies at the interface

  12. Efficient mold Danscooling optimization by using model reduction

    E-Print Network [OSTI]

    Mongeau, Marcel

    .Chinesta@ec-nantes.fr ABSTRACT Optimization and inverse identification are two procedures usually encountered in many industrial the polymer melt into the mold. Its screw rotates and axially reciprocates to melt, mix, and pump the polymer to evacuate the heat since polymers are bad conductors as thermal conductivity #12;ranges form 0.1 W/mK to 1

  13. Simulation and Optimization Models for Scheduling Multi-step Sequential Procedures in Nuclear Medicine 

    E-Print Network [OSTI]

    Perez Roman, Eduardo

    2011-08-08

    (DEVS) simulation model for nuclear medicine patient service management that considers both patient and management perspectives. DEVS is a formal modeling and simulation framework based on dynamical systems theory and provides well de ned concepts...

  14. Computational fluid dynamics modeling of coal gasification in a pressurized spout-fluid bed

    SciTech Connect (OSTI)

    Zhongyi Deng; Rui Xiao; Baosheng Jin; He Huang; Laihong Shen; Qilei Song; Qianjun Li [Southeast University, Nanjing (China). Key Laboratory of Clean Coal Power Generation and Combustion Technology of Ministry of Education

    2008-05-15

    Computational fluid dynamics (CFD) modeling, which has recently proven to be an effective means of analysis and optimization of energy-conversion processes, has been extended to coal gasification in this paper. A 3D mathematical model has been developed to simulate the coal gasification process in a pressurized spout-fluid bed. This CFD model is composed of gas-solid hydrodynamics, coal pyrolysis, char gasification, and gas phase reaction submodels. The rates of heterogeneous reactions are determined by combining Arrhenius rate and diffusion rate. The homogeneous reactions of gas phase can be treated as secondary reactions. A comparison of the calculated and experimental data shows that most gasification performance parameters can be predicted accurately. This good agreement indicates that CFD modeling can be used for complex fluidized beds coal gasification processes. 37 refs., 7 figs., 5 tabs.

  15. Computational Fluid Dynamics (CFD) Modelling on Soot Yield for Fire

    E-Print Network [OSTI]

    Computational Fluid Dynamics (CFD) Modelling on Soot Yield for Fire Engineering Assessment Yong S (CFD) Modelling is now widely used by fire safety engineers throughout the world as a tool of the smoke control design as part of the performance based fire safety design in the current industry

  16. Dislocation dynamics: from microscopic models to macroscopic crystal plasticity

    E-Print Network [OSTI]

    El Hajj, Ahmad

    Dislocation dynamics: from microscopic models to macroscopic crystal plasticity A. El Hajj , H study ranges from atomic models to macroscopic crystal plasticity. At each scale, dislocations can crystal Z3 where each position with integer coordinates is occupied by one atom. We want to describe

  17. Fluid Dynamic Models of Flagellar and Ciliary Beating

    E-Print Network [OSTI]

    Fauci, Lisa

    University, New Orleans, Louisiana, USA ABSTRACT: We have developed a fluid­mechanical model of a eucaryotic mechanics of microtubules, and forces due to nexin links with a surrounding incompressible fluid. This model mechanisms, the passive elastic structure of the axoneme, and the external fluid dynamics. These flagellar

  18. SIMULATING MARKET TRANSFORMATION DYNAMICS USING A HYBRID ENERGY ECONOMY MODEL

    E-Print Network [OSTI]

    ii SIMULATING MARKET TRANSFORMATION DYNAMICS USING A HYBRID ENERGY ECONOMY MODEL: A LOOK the likely effects of alternative policies, potential adoption rates of clean technologies, and costs to society in the long run. My goal was to use a "hybrid" energy economy model (CIMS), which combines

  19. A STOCHASTIC CELLULAR AUTOMATON MODEL OF EBOLA VIRUS DYNAMICS

    E-Print Network [OSTI]

    Hawkins, Jane M.

    A STOCHASTIC CELLULAR AUTOMATON MODEL OF EBOLA VIRUS DYNAMICS E. BURKHEAD AND J. HAWKINS Abstract. We construct a stochastic cellular automaton (SCA) model for the spread of the Ebola virus (EBOV). We of virus and the typical immune response to it, and the differences which reflect the drastically different

  20. Assessing the reliability of linear dynamic transformer thermal modelling

    E-Print Network [OSTI]

    Assessing the reliability of linear dynamic transformer thermal modelling X. Mao, D.J. Tylavsky and G.A. McCulla Abstract: Improving the utilisation of transformers requires that the hot-spot and top. An alternative method for assessing transformer model reliability is provided. 1 Introduction The maximally

  1. A Dynamic Model coupling Photoacclimation and Photoinhibition in Microalgae

    E-Print Network [OSTI]

    Boyer, Edmond

    in microalgae, thereby spanning multiple time scales. The properties of the model are investigated under quasi2 mitigation due to their inherent consumption of CO2 during photosynthesis, they can be coupledA Dynamic Model coupling Photoacclimation and Photoinhibition in Microalgae Philipp Hartmann1

  2. Numerically Estimating Internal Models of Dynamic Virtual Objects

    E-Print Network [OSTI]

    Sekuler, Robert

    human subjects to manipulate a computer-animated virtual object. This virtual object (vO) was a high, human cognition, human information processing, ideal performer, internal model, virtual object, virtual, specifically how humans acquire an internal model of a dynamic virtual object. Our methodology minimizes

  3. Modeling and simulation of consumer response to dynamic pricing.

    SciTech Connect (OSTI)

    Valenzuela, J.; Thimmapuram, P.; Kim, J (Decision and Information Sciences); (Auburn Univ.)

    2012-08-01

    Assessing the impacts of dynamic-pricing under the smart grid concept is becoming extremely important for deciding its full deployment. In this paper, we develop a model that represents the response of consumers to dynamic pricing. In the model, consumers use forecasted day-ahead prices to shift daily energy consumption from hours when the price is expected to be high to hours when the price is expected to be low while maintaining the total energy consumption as unchanged. We integrate the consumer response model into the Electricity Market Complex Adaptive System (EMCAS). EMCAS is an agent-based model that simulates restructured electricity markets. We explore the impacts of dynamic-pricing on price spikes, peak demand, consumer energy bills, power supplier profits, and congestion costs. A simulation of an 11-node test network that includes eight generation companies and five aggregated consumers is performed for a period of 1 month. In addition, we simulate the Korean power system.

  4. Dynamical many-body localization in an integrable model

    E-Print Network [OSTI]

    Aydin Cem Keser; Sriram Ganeshan; Gil Refael; Victor Galitski

    2015-06-17

    We investigate dynamical many-body localization and delocalization in an integrable system of periodically-kicked, interacting linear rotors. The Hamiltonian we investigate is linear in momentum, and its Floquet evolution operator is analytically tractable for arbitrary interaction strengths. One of the hallmarks of this model is that depending on certain parameters, it manifest both localization and delocalization in momentum space. We explicitly show that, for this model, the energy being bounded at long times is not a sufficient condition for dynamical localization. Besides integrals of motion associated to the integrability, this model manifests additional integrals of motion, which are the exclusive consequence of dynamical many-body localization. We also propose an experimental scheme, involving voltage-biased Josephson junctions, to realize such many-body kicked models.

  5. Active and Accelerated Learning of Cost Models for Optimizing Scientific Applications

    E-Print Network [OSTI]

    Chase, Jeffrey S.

    Active and Accelerated Learning of Cost Models for Optimizing Scientific Applications Piyush Shivam of sciences including astrophysics, bioinformatics, systems biology, and climate modeling [15, 31]. This new University chase@cs.duke.edu ABSTRACT We present the NIMO system that automatically learns cost models

  6. DYNAMICAL MODEL OF AN EXPANDING SHELL

    SciTech Connect (OSTI)

    Pe'er, Asaf [Harvard-Smithsonian Center for Astrophysics, MS-51, 60 Garden Street, Cambridge, MA 02138 (United States)

    2012-06-10

    Expanding blast waves are ubiquitous in many astronomical sources, such as supernova remnants, X-ray emitting binaries, and gamma-ray bursts. I consider here the dynamics of such an expanding blast wave, both in the adiabatic and the radiative regimes. As the blast wave collects material from its surroundings, it decelerates. A full description of the temporal evolution of the blast wave requires consideration of both the energy density and the pressure of the shocked material. The obtained equation is different from earlier works in which only the energy was considered. The solution converges to the familiar results in both the ultrarelativistic and the sub-relativistic (Newtonian) regimes.

  7. optimal initial conditions for coupling ice sheet models to earth...

    Office of Scientific and Technical Information (OSTI)

    for coupling ice sheet models to earth system models Authors: Perego, Mauro 1 ; Price, Stephen F. Dr 2 ; Stadler, Georg 3 + Show Author Affiliations Sandia National...

  8. Optimal Initial Conditions for Coupling Ice Sheet Models to Earth...

    Office of Scientific and Technical Information (OSTI)

    Sheet Models to Earth System Models. Abstract not provided. Authors: Perego, Mauro ; Price, Stephen ; Stadler, Georg Publication Date: 2014-04-01 OSTI Identifier: 1142266 Report...

  9. Slow dynamics in a model of the cellulose network

    E-Print Network [OSTI]

    O. V. Manyuhina; A. Fasolino; M. I. Katsnelson

    2007-06-07

    We present numerical simulations of a model of cellulose consisting of long stiff rods, representing cellulose microfibrils, connected by stretchable crosslinks, representing xyloglucan molecules, hydrogen bonded to the microfibrils. Within a broad range of temperature the competing interactions in the resulting network give rise to a slow glassy dynamics. In particular, the structural relaxation described by orientational correlation functions shows a logarithmic time dependence. The glassy dynamics is found to be due to the frustration introduced by the network of xyloglucan molecules. Weakening of interactions between rod and xyloglucan molecules results in a more marked reorientation of cellulose microfibrils, suggesting a possible mechanism to modify the dynamics of the plant cell wall.

  10. STOCHASTIC DYNAMICS OF A COUPLED ATMOSPHEREOCEAN MODEL

    E-Print Network [OSTI]

    's longwave radiation coefficient and the shortwave solar radiation profile. Third, we have demon- strated this coupled atmosphere-ocean model consists of stochastic Date: February 5, 2002. 1991 Mathematics Subject

  11. Generative modeling of dynamic visual scenes

    E-Print Network [OSTI]

    Lin, Dahua, Ph. D. Massachusetts Institute of Technology

    2012-01-01

    Modeling visual scenes is one of the fundamental tasks of computer vision. Whereas tremendous efforts have been devoted to video analysis in past decades, most prior work focuses on specific tasks, leading to dedicated ...

  12. Modeling Infection with Multi-agent Dynamics

    E-Print Network [OSTI]

    Dong, Wen

    2012-01-01

    Developing the ability to comprehensively study infections in small populations enables us to improve epidemic models and better advise individuals about potential risks to their health. We currently have a limited ...

  13. Nanoscale SRAM Variability and Optimization

    E-Print Network [OSTI]

    Toh, Seng Oon

    2011-01-01

    Dynamic Read Stability 5 Stochastic Optimization of SRAM 5.15.2 Bitcell Optimization . . . . . . . . .5.2.1 GlobalTechnology . . Optimization . . . . . . Read and Write

  14. Empirical Performance Model-Driven Data Layout Optimization and Library Call Selection for Tensor Contraction Expressions

    SciTech Connect (OSTI)

    Lu, Qingda; Gao, Xiaoyang; Krishnamoorthy, Sriram; Baumgartner, Gerald; Ramanujam, J.; Sadayappan, Ponnuswamy

    2012-03-01

    Empirical optimizers like ATLAS have been very effective in optimizing computational kernels in libraries. The best choice of parameters such as tile size and degree of loop unrolling is determined by executing different versions of the computation. In contrast, optimizing compilers use a model-driven approach to program transformation. While the model-driven approach of optimizing compilers is generally orders of magnitude faster than ATLAS-like library generators, its effectiveness can be limited by the accuracy of the performance models used. In this paper, we describe an approach where a class of computations is modeled in terms of constituent operations that are empirically measured, thereby allowing modeling of the overall execution time. The performance model with empirically determined cost components is used to perform data layout optimization together with the selection of library calls and layout transformations in the context of the Tensor Contraction Engine, a compiler for a high-level domain-specific language for expressing computational models in quantum chemistry. The effectiveness of the approach is demonstrated through experimental measurements on representative computations from quantum chemistry.

  15. Optimized shooting method for finding periodic orbits of nonlinear dynamical systems

    E-Print Network [OSTI]

    W. Dednam; A. E. Botha

    2014-08-14

    An alternative numerical method is developed to find stable and unstable periodic orbits of nonlinear dynamical systems. The method exploits the high-efficiency of the Levenberg-Marquardt algorithm for medium-sized problems and has the additional advantage of being relatively simple to implement. It is also applicable to both autonomous and non-autonomous systems. As an example of its use, it is employed to find periodic orbits in the R\\"ossler system, a coupled R\\"ossler system, as well as an eight-dimensional model of a flexible rotor-bearing; problems which have been treated previously via two related methods. The results agree with the previous methods and are seen to be more accurate in some cases. A simple implementation of the method, written in the Python programming language, is provided as an Appendix.

  16. CSAW: a dynamical model of protein folding

    E-Print Network [OSTI]

    Kerson Huang

    2006-01-12

    CSAW (conditioned self-avoiding walk) is a model of protein folding that combines SAW (self-avoiding walk) with Monte-Carlo. It simulates the Brownian motion of a chain molecule in the presence of interactions, both among chain residues, and with the environment. In a first model that includes the hydrophobic effect and hydrogen bonding, a chain of 30 residues folds into a native state with stable secondary and tertiary structures. The process starts with a rapid collapse into an intermediate "molten globule", which slowly decays into the native state afer a relatively long quiescent period. The behavior of the radius of gyration mimics experimental data.

  17. Analytical properties of a three-compartmental dynamical demographic model

    E-Print Network [OSTI]

    E. B. Postnikov

    2015-07-29

    The three-compartmental demographic model by Korotaeyv-Malkov-Khaltourina, connecting population size, economic surplus, and educational level, is considered from the point of view of dynamical systems theory. It is shown that there exist two integrals of motion, which enable the system to be reduced to one non-linear ordinary differential equation. The study of its structure provides analytical criteria for the dominance ranges of the dynamics of Malthus and Kremer. Additionally, the particular ranges of parameters enable the derived general ordinary differential equations to be reduced to the models of Gompertz and Thoularis-Wallace.

  18. Modeling the influence of polls on elections: a population dynamics approach

    SciTech Connect (OSTI)

    Hyman, James M; Restrepo, Juan M; Rael, Rosalyn C

    2009-01-01

    We propose a population dynamics model for quantifying the effects of polling data on the outcome of multi-party elections decided by a majority-rule voting process. We divide the population into two groups: committed voters impervious to polling data, and susceptible voters whose decision to vote is influenced by data, depending on its reliability. This population-based approach to modeling the process sidesteps the problem of upscaling models based upon the choices made by individuals. We find releasing poll data is not advantageous to leading candidates, but it can be exploited by those closely trailing. The analysis identifies the particular type of voting impetus at play in different stages of an election and could help strategists optimize their influence on susceptible voters.

  19. A system-level cost-of-energy wind farm layout optimization with landowner modeling

    SciTech Connect (OSTI)

    Chen, Le [Ames Laboratory; MacDonald, Erin [Ames Laboratory

    2013-10-01

    This work applies an enhanced levelized wind farm cost model, including landowner remittance fees, to determine optimal turbine placements under three landowner participation scenarios and two land-plot shapes. Instead of assuming a continuous piece of land is available for the wind farm construction, as in most layout optimizations, the problem formulation represents landowner participation scenarios as a binary string variable, along with the number of turbines. The cost parameters and model are a combination of models from the National Renewable Energy Laboratory (NREL), Lawrence Berkeley National Laboratory, and Windustiy. The system-level cost-of-energy (COE) optimization model is also tested under two land-plot shapes: equally-sized square land plots and unequal rectangle land plots. The optimal COEs results are compared to actual COE data and found to be realistic. The results show that landowner remittances account for approximately 10% of farm operating costs across all cases. Irregular land-plot shapes are easily handled by the model. We find that larger land plots do not necessarily receive higher remittance fees. The model can help site developers identify the most crucial land plots for project success and the optimal positions of turbines, with realistic estimates of costs and profitability. (C) 2013 Elsevier Ltd. All rights reserved.

  20. Variable horizon model predictive control: robustness and optimality

    E-Print Network [OSTI]

    Shekhar, Rohan Chandra

    2012-07-03

    . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 6.3 Kinematic vectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 6.4 Mechanism model showing generalised coordinates . . . . . . . . . . . . . . . . 109 6.5 Static balance of material failure forces... .1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 6.1.1 Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 6.2 Mechanism Model...

  1. Model Order Reduction in Porous Media Flow Simulation and Optimization 

    E-Print Network [OSTI]

    Ghasemi, Mohammadreza

    2015-05-06

    Subsurface flow modeling and simulation is ubiquitous in many energy related processes, including oil and gas production. These models are usually large scale and simulating them can be very computationally demanding, particularly in work...

  2. Model Based Safety Assessment Dynamic System

    E-Print Network [OSTI]

    Grigoras, .Romulus

    Assessment Techniques ·Failure mode and effect analysis (FMEA) ­ Model: from a local failure to its system chain .... 2 Functional FMEA template FT unannunciated loss of wheel braking #12;Drawbacks of the Classical Safety Assessment Techniques · Fault Tree, FMEA ­ Give failure propagation paths without referring

  3. Improved Crosstalk Modeling for Noise Constrained Interconnect Optimization Jason Cong, David Zhigang Pan and Prasanna V. Srinivas

    E-Print Network [OSTI]

    Pan, David Z.

    Improved Crosstalk Modeling for Noise Constrained Interconnect Optimization Jason Cong, David This paper presents a much improved, highly accurate yet effi- cient crosstalk noise model, the 2-¢ model, and applies it to noise- constrained interconnect optimizations. Compared with previous crosstalk noise models

  4. Capacity analysis, cycle time optimization, and supply chain strategy in multi-product biopharmaceutical manufacturing operations

    E-Print Network [OSTI]

    Fetcho-Phillips, Kacey L. (Kacey Lynn)

    2011-01-01

    Application of system optimization theory, supply chain principles, and capacity modeling are increasingly valuable tools for use in pharmaceutical manufacturing facilities. The dynamics of the pharmaceutical industry - ...

  5. THE APPLICATION OF AN EVOLUTIONARY ALGORITHM TO THE OPTIMIZATION OF A MESOSCALE METEOROLOGICAL MODEL

    SciTech Connect (OSTI)

    Werth, D.; O'Steen, L.

    2008-02-11

    We show that a simple evolutionary algorithm can optimize a set of mesoscale atmospheric model parameters with respect to agreement between the mesoscale simulation and a limited set of synthetic observations. This is illustrated using the Regional Atmospheric Modeling System (RAMS). A set of 23 RAMS parameters is optimized by minimizing a cost function based on the root mean square (rms) error between the RAMS simulation and synthetic data (observations derived from a separate RAMS simulation). We find that the optimization can be efficient with relatively modest computer resources, thus operational implementation is possible. The optimization efficiency, however, is found to depend strongly on the procedure used to perturb the 'child' parameters relative to their 'parents' within the evolutionary algorithm. In addition, the meteorological variables included in the rms error and their weighting are found to be an important factor with respect to finding the global optimum.

  6. An Optimization Model for Plug-In Hybrid Electric Vehicles

    SciTech Connect (OSTI)

    Malikopoulos, Andreas [ORNL] [ORNL; Smith, David E [ORNL] [ORNL

    2011-01-01

    The necessity for environmentally conscious vehicle designs in conjunction with increasing concerns regarding U.S. dependency on foreign oil and climate change have induced significant investment towards enhancing the propulsion portfolio with new technologies. More recently, plug-in hybrid electric vehicles (PHEVs) have held great intuitive appeal and have attracted considerable attention. PHEVs have the potential to reduce petroleum consumption and greenhouse gas (GHG) emissions in the commercial transportation sector. They are especially appealing in situations where daily commuting is within a small amount of miles with excessive stop-and-go driving. The research effort outlined in this paper aims to investigate the implications of motor/generator and battery size on fuel economy and GHG emissions in a medium-duty PHEV. An optimization framework is developed and applied to two different parallel powertrain configurations, e.g., pre-transmission and post-transmission, to derive the optimal design with respect to motor/generator and battery size. A comparison between the conventional and PHEV configurations with equivalent size and performance under the same driving conditions is conducted, thus allowing an assessment of the fuel economy and GHG emissions potential improvement. The post-transmission parallel configuration yields higher fuel economy and less GHG emissions compared to pre-transmission configuration partly attributable to the enhanced regenerative braking efficiency.

  7. Optimization Tansu Alpcan

    E-Print Network [OSTI]

    Hutter, Marcus

    Optimization Difficulty Tansu Alpcan Introduction Definitions and Model Optimization Difficulty Bounds on Optimization Difficulty Conclusion Can we measure the difficulty of an optimization problem Science Australian National University ITW 2014, Hobart 1 / 22 #12;Optimization Difficulty Tansu Alpcan

  8. Thermodynamic modeling and optimization of a screw compressor chiller and cooling tower system 

    E-Print Network [OSTI]

    Graves, Rhett David

    2004-09-30

    , absorption, thermoelectric, and thermoacoustic (Gordon and Ng 1995). Chiller models have been used to predict the performance of thermal storage 6 systems (Henze et al. 1997) and whole chiller plant systems (Lau et al. 1985). Chiller models have also been... used to aid in the development of control algorithms for chiller plants (Flake et al. 1997). There have been several attempts to generate an ?optimal? operating scheme using the Whillier cooling tower model, a chiller model, or a combination of both...

  9. Green Algae as Model Organisms for Biological Fluid Dynamics

    E-Print Network [OSTI]

    Goldstein, Raymond E

    2014-01-01

    In the past decade the volvocine green algae, spanning from the unicellular $Chlamydomonas$ to multicellular $Volvox$, have emerged as model organisms for a number of problems in biological fluid dynamics. These include flagellar propulsion, nutrient uptake by swimming organisms, hydrodynamic interactions mediated by walls, collective dynamics and transport within suspensions of microswimmers, the mechanism of phototaxis, and the stochastic dynamics of flagellar synchronization. Green algae are well suited to the study of such problems because of their range of sizes (from 10 $\\mu$m to several millimetres), their geometric regularity, the ease with which they can be cultured and the availability of many mutants that allow for connections between molecular details and organism-level behavior. This review summarizes these recent developments and highlights promising future directions in the study of biological fluid dynamics, especially in the context of evolutionary biology, that can take advantage of these re...

  10. Green Algae as Model Organisms for Biological Fluid Dynamics

    E-Print Network [OSTI]

    Raymond E. Goldstein

    2014-09-08

    In the past decade the volvocine green algae, spanning from the unicellular $Chlamydomonas$ to multicellular $Volvox$, have emerged as model organisms for a number of problems in biological fluid dynamics. These include flagellar propulsion, nutrient uptake by swimming organisms, hydrodynamic interactions mediated by walls, collective dynamics and transport within suspensions of microswimmers, the mechanism of phototaxis, and the stochastic dynamics of flagellar synchronization. Green algae are well suited to the study of such problems because of their range of sizes (from 10 $\\mu$m to several millimetres), their geometric regularity, the ease with which they can be cultured and the availability of many mutants that allow for connections between molecular details and organism-level behavior. This review summarizes these recent developments and highlights promising future directions in the study of biological fluid dynamics, especially in the context of evolutionary biology, that can take advantage of these remarkable organisms.

  11. Modeling Dynamic Landscapes in Open Source GIS

    E-Print Network [OSTI]

    Mitasova, Helena

    2013-11-20

    is free online • message board discussion, help • Google sites: post HW, get feedback • register to get credit Solar radiation modeling: monthly totals Applications in urban areas: solar panels, building design, thermal conditions,… Helena Mitasova, NCSU... topics: • Solar energy potential • Coastal hazards • Watershed analysis • Trail and greenway design • Lidar data processing Most students use ArcGIS but number of students who use GRASS for at least part of their project is increasing every semester...

  12. An efficient model of drillstring dynamics

    E-Print Network [OSTI]

    Butlin, T.; Langley, R. S.

    2015-07-23

    Vibration problems represent a significant cost to the oilwell drilling industry due to a wide range of problematic phenomena that can occur [1]. Torsional vibration can cause fatigue, damage to the drillbit if the direction of rotation periodically reverses... ,14]). There are many other effects that could be included in a drillstring model, such as fluid-structure interaction, the effect of free particles at frictional and cutting interfaces, well-path tortu- osity, mud-pump excitation, and buckling. It is clear...

  13. Concurrent Optimization of Consumer's Electrical Energy Bill and Producer's Power Generation Cost under a Dynamic Pricing

    E-Print Network [OSTI]

    Pedram, Massoud

    Concurrent Optimization of Consumer's Electrical Energy Bill and Producer's Power Generation Cost their electric bill. On the other hand optimizing the number and production time of power generation facilities lower cost. I. INTRODUCTION There is no substitute for the status of electrical energy, which

  14. Instrumenting V8 to Measure the Efficacy of Dynamic Optimizations on Production Code

    E-Print Network [OSTI]

    websites, such as Gmail and Facebook, are made possible by extensive and complex use of the language optimization requires overhead to actually perform the compilation that could have instead been occupied optimization techniques fare on the real-world, popular workloads such as Gmail and Facebook. Though

  15. Dynamic crack initiation toughness : experiments and peridynamic modeling.

    SciTech Connect (OSTI)

    Foster, John T.

    2009-10-01

    This is a dissertation on research conducted studying the dynamic crack initiation toughness of a 4340 steel. Researchers have been conducting experimental testing of dynamic crack initiation toughness, K{sub Ic}, for many years, using many experimental techniques with vastly different trends in the results when reporting K{sub Ic} as a function of loading rate. The dissertation describes a novel experimental technique for measuring K{sub Ic} in metals using the Kolsky bar. The method borrows from improvements made in recent years in traditional Kolsky bar testing by using pulse shaping techniques to ensure a constant loading rate applied to the sample before crack initiation. Dynamic crack initiation measurements were reported on a 4340 steel at two different loading rates. The steel was shown to exhibit a rate dependence, with the recorded values of K{sub Ic} being much higher at the higher loading rate. Using the knowledge of this rate dependence as a motivation in attempting to model the fracture events, a viscoplastic constitutive model was implemented into a peridynamic computational mechanics code. Peridynamics is a newly developed theory in solid mechanics that replaces the classical partial differential equations of motion with integral-differential equations which do not require the existence of spatial derivatives in the displacement field. This allows for the straightforward modeling of unguided crack initiation and growth. To date, peridynamic implementations have used severely restricted constitutive models. This research represents the first implementation of a complex material model and its validation. After showing results comparing deformations to experimental Taylor anvil impact for the viscoplastic material model, a novel failure criterion is introduced to model the dynamic crack initiation toughness experiments. The failure model is based on an energy criterion and uses the K{sub Ic} values recorded experimentally as an input. The failure model is then validated against one class of problems showing good agreement with experimental results.

  16. Optimal Charging Profiles with Minimal Intercalation-Induced Stresses for Lithium-Ion Batteries Using Reformulated Pseudo 2-Dimensional Models

    SciTech Connect (OSTI)

    Suthar, B; Northrop, PWC; Braatz, RD; Subramanian, VR

    2014-07-30

    This paper illustrates the application of dynamic optimization in obtaining the optimal current profile for charging a lithium-ion battery by restricting the intercalation-induced stresses to a pre-determined limit estimated using a pseudo 2-dimensional (P2D). model. This paper focuses on the problem of maximizing the charge stored in a given time while restricting capacity fade due to intercalation-induced stresses. Conventional charging profiles for lithium-ion batteries (e.g., constant current followed by constant voltage or CC-CV) are not derived by considering capacity fade mechanisms, which are not only inefficient in terms of life-time usage of the batteries but are also slower by not taking into account the changing dynamics of the system. (C) The Author(s) 2014. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives 4.0 License (CC BY-NC-ND, http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial reuse, distribution, and reproduction in any medium, provided the original work is not changed in any way and is properly cited. For permission for commercial reuse, please email: oa@electrochem.org. All rights reserved.

  17. STRUCTURAL VALIDATION OF SYSTEM DYNAMICS AND AGENT-BASED SIMULATION MODELS

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    , population dynamics, energy systems, and urban planning. The usefulness of these models is predicated including global warming, population dynamics, energy systems, and urban planning simply defy a face

  18. Handling risk of uncertainty in model-based production optimization: a

    E-Print Network [OSTI]

    Van den Hof, Paul

    .d.Jansen@tudelft.nl) Abstract: Model-based economic optimization of oil production suffers from high levels of uncertainty, the secondary objective is aimed at maximizing the speed of oil production to mitigate risk. This multi and production data about the true values of the model parameters. Furthermore, economic variables such as oil

  19. A Mathematical Programming Model for Optimal Layout Considering Quantitative Risk Analysis

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    A Mathematical Programming Model for Optimal Layout Considering Quantitative Risk Analysis Nancy risk analysis; Plant layout *Corresponding author. Phone: +52-461-611-7575 Ext. 5577. E-mail: arturo of plant layout with safety considerations. The model considers a quantitative risk analysis to take safety

  20. An optimizing reduced order FDS for the tropical Pacific Ocean reduced gravity model

    E-Print Network [OSTI]

    Aluffi, Paolo

    An optimizing reduced order FDS for the tropical Pacific Ocean reduced gravity model Zhendong Luoa) for the tropical Pacific Ocean reduced gravity model. Ensembles of data are compiled from transient solutions computed from the discrete equation system derived by FDS for the tropical Pacific Ocean reduced gravity

  1. OLAF ---A General Modeling System to Evaluate and Optimize the Location of an Air

    E-Print Network [OSTI]

    Fliege, Jörg

    OLAF --- A General Modeling System to Evaluate and Optimize the Location of an Air Polluting.2 The Air Dispersion Model . . . . . . . . . . . . . . . . . . . . . 14 3 Ecology and Chemokinetics 17 3 . . . . . . . . . . . . . . . . . . . . . . . 48 6.1.3 Meteorological Data . . . . . . . . . . . . . . . . . . . . 48 6.1.4 Pollutant Data

  2. Optimizing a Model for Siting Offshore Wind Farms using a Genetic Algorithm

    E-Print Network [OSTI]

    Mountziaris, T. J.

    Optimizing a Model for Siting Offshore Wind Farms using a Genetic Algorithm *Michael Ameckson Science Foundation. Generating electricity using offshore wind farms can assist coastal regions to meet growing electricity demands supported by a renewable source [4]. However modeling wind farm siting must

  3. Modeling and Optimization Issues Concerning a Circular Piezoelectric Actuator Design \\Lambda

    E-Print Network [OSTI]

    Modeling and Optimization Issues Concerning a Circular Piezoelectric Actuator Design \\Lambda Steven Raleigh, NC 27695 Abstract An electromechanical model for a circular piezoelectric actuator is developed and analyzed. A crit­ ical challenge in certain applications employing piezoceramic actuators is to maximize

  4. Modeling and Optimization of RF-MEMS Reconfigurable Tuners with Computationally Efficient Time-Domain Techniques

    E-Print Network [OSTI]

    Tentzeris, Manos

    Modeling and Optimization of RF-MEMS Reconfigurable Tuners with Computationally Efficient Time of Technology, Atlanta, GA 30332 2 Raytheon Company, Tucson AZ, 85734 Abstract -- Modern RF-MEMS device design methods in which the FDTD technique can be used to model a reconfigurable RF-MEMS tuner. A new method

  5. Optimization of large-scale heterogeneous system-of-systems models.

    SciTech Connect (OSTI)

    Parekh, Ojas; Watson, Jean-Paul; Phillips, Cynthia Ann; Siirola, John; Swiler, Laura Painton; Hough, Patricia Diane (Sandia National Laboratories, Livermore, CA); Lee, Herbert K. H. (University of California, Santa Cruz, Santa Cruz, CA); Hart, William Eugene; Gray, Genetha Anne (Sandia National Laboratories, Livermore, CA); Woodruff, David L. (University of California, Davis, Davis, CA)

    2012-01-01

    Decision makers increasingly rely on large-scale computational models to simulate and analyze complex man-made systems. For example, computational models of national infrastructures are being used to inform government policy, assess economic and national security risks, evaluate infrastructure interdependencies, and plan for the growth and evolution of infrastructure capabilities. A major challenge for decision makers is the analysis of national-scale models that are composed of interacting systems: effective integration of system models is difficult, there are many parameters to analyze in these systems, and fundamental modeling uncertainties complicate analysis. This project is developing optimization methods to effectively represent and analyze large-scale heterogeneous system of systems (HSoS) models, which have emerged as a promising approach for describing such complex man-made systems. These optimization methods enable decision makers to predict future system behavior, manage system risk, assess tradeoffs between system criteria, and identify critical modeling uncertainties.

  6. An intelligent floor field cellular automata model for pedestrian dynamics

    E-Print Network [OSTI]

    Ekaterina Kirik; Tat'yana Yurgel'yan; Dmitriy Krouglov

    2009-06-15

    A stochastic cellular automata (CA) model for pedestrian dynamics is presented. Our goal is to simulate different types of pedestrian movement, from regular to panic. But here we emphasize regular situations which imply that pedestrians analyze environment and choose their route more carefully. And transition probabilities have to depict such effect. The potentials of floor fields and environment analysis are combined in the model obtained. People patience is included in the model. This makes simulation of pedestrians movement more realistic. Some simulation results are presented and comparison with basic FF-model is made.

  7. Approximate Dynamic Programming for Networks: Fluid Models and Constraint Reduction

    E-Print Network [OSTI]

    Veatch, Michael H.

    of approximating functions for the differential cost. The first contribution of this paper is identifying new or piece-wise quadratic. Fluid cost has been used to initialize the value iteration algorithm [5Approximate Dynamic Programming for Networks: Fluid Models and Constraint Reduction Michael H

  8. Counterclockwise Dynamics of a Rate-Independent Semilinear Duhem Model

    E-Print Network [OSTI]

    Bernstein, Dennis S.

    Counterclockwise Dynamics of a Rate-Independent Semilinear Duhem Model Ashwani K. Padthe, Jin of a hysteretic simple closed curve. In magnetics, hysteresis caused by the irreversible flux-change mechanism dissipates energy in the form of heat [2]. In both cases, the energy dissipated in one cycle is equal

  9. Dynamic and Static Influence Models on Starbucks Networks Minkyoung Kim

    E-Print Network [OSTI]

    Dynamic and Static Influence Models on Starbucks Networks Minkyoung Kim Interdisciplinary Program Starbucks stores in Korea, which have been spread most rapidly in the world, as an exemplary social network for Starbucks to open the 100th store in Korea, which is the fastest growth of Starbucks in the world [10

  10. GLOBAL DYNAMICS OF AN SEIR EPIDEMIC MODEL WITH VERTICAL TRANSMISSION

    E-Print Network [OSTI]

    Li, Michael

    GLOBAL DYNAMICS OF AN SEIR EPIDEMIC MODEL WITH VERTICAL TRANSMISSION MICHAEL Y. LI, HAL L. SMITH population through both horizontal and vertical transmission. The total host population is assumed to have at an endemic equilibrium state if it initially exists. The contribution of the vertical transmission

  11. Modeling Combined Time-and Event-Driven Dynamic Systems

    E-Print Network [OSTI]

    Baclawski, Kenneth B.

    such as logistical systems, distributed sensor sys- tems and intelligent highway vehicle systems, are complex dynamic. In this approach, future behaviors are generated through quantitative simulation which "executes" a simulation model, typically at fixed time steps, to obtain quantitative values of state and/or output variables. 1

  12. Multiscale modeling of polystyrene dynamics in different environments

    E-Print Network [OSTI]

    Faller, Roland

    Multiscale modeling of polystyrene dynamics in different environments Qi Sun1 , Florence Pon1 simulations can address not only the average properties of the system but also the distribution over any component in their neighborhood and vice versa. The simulation temperature of 450 K is chosen to be above

  13. Geographical Information Systems and Dynamic Modeling via Agent Based Systems

    E-Print Network [OSTI]

    de Figueiredo, Luiz Henrique

    Geographical Information Systems and Dynamic Modeling via Agent Based Systems Cláudio Antônio da fariasol@eng.uerj.br ABSTRACT A full integration among Geographical Information Systems and Agent Based integrated with Geographical Information Systems (GIS). The first one is the movement of pedestrians

  14. Modelling microbial population dynamics in nitritation processes Elisabetta Giusti a

    E-Print Network [OSTI]

    Modelling microbial population dynamics in nitritation processes Elisabetta Giusti a , Stefano. Marta 3, I-50139 Florence, Italy b ENEA, Italian National Agency for New Technologies, Energy January 2011 Accepted 1 February 2011 Available online 3 March 2011 Keywords: Microbial kinetics Activated

  15. Lessons Learned from Quantitative Dynamical Modeling in Systems Biology

    E-Print Network [OSTI]

    Timmer, Jens

    Lessons Learned from Quantitative Dynamical Modeling in Systems Biology Andreas Raue1,2 *. , Marcel of Physics, University of Freiburg, Freiburg, Germany, 2 Institute of Computational Biology, Helmholtz Center, Munich, Germany, 3 Systems Biology of Signal Transduction, German Cancer Research Center

  16. Transport coefficients of a mesoscopic fluid dynamics model

    E-Print Network [OSTI]

    N. Kikuchi; C. M. Pooley; J. F. Ryder; J. M. Yeomans

    2003-02-21

    We investigate the properties of stochastic rotation dynamics (Malevanets-Kapral method), a mesoscopic model used for simulating fluctuating hydrodynamics. Analytical results are given for the transport coefficients. We discuss the most efficient way of measuring the transport properties and obtain excellent agreement between the theoretical and numerical calculations.

  17. Parameterized Model Order Reduction of Nonlinear Dynamical Systems

    E-Print Network [OSTI]

    Reif, Rafael

    Parameterized Model Order Reduction of Nonlinear Dynamical Systems Brad Bond Research Laboratory reduction technique for non-linear systems. Our approach combines an existing non-parameterized trajectory piecewise linear method for non-linear systems, with an existing moment matching param- eterized technique

  18. Modeling the Dynamic Interaction of Hebbian and Homeostatic Plasticity

    E-Print Network [OSTI]

    Stryker, Michael

    Neuron Article Modeling the Dynamic Interaction of Hebbian and Homeostatic Plasticity Taro.toyoizumi@brain.riken.jp http://dx.doi.org/10.1016/j.neuron.2014.09.036 SUMMARY Hebbian and homeostatic plasticity together of plasticity directly modifies synaptic strength. Equilibrium is reached when the two are inducing equal

  19. Modelling of the static and dynamic mechanical properties of human

    E-Print Network [OSTI]

    Haslwanter, Thomas

    Modelling of the static and dynamic mechanical properties of human otoliths DISSERTATION zur of the city of Paris #12;#12;Abstract The aim of this study is a numerical investigation of the static in the inner ears. They sense accelerations of the head. In the static case, information retrieved from them

  20. Dynamic Modelling and Control Design of Pre-combustion Power

    E-Print Network [OSTI]

    Foss, Bjarne A.

    principles. The pre- combustion gas power cycle plants consist of reformers and separation units, com and control design of two pre-combustion power cycles, i.e., a hydro- gen membrane reformer (HMR) based power- pressors, gas and steam turbines and a heat recovery system. Analysis of dynamic models at an early stage

  1. Dynamical Model of Rocket Propellant Loading with Liquid Hydrogen

    E-Print Network [OSTI]

    Muratov, Cyrill

    when liquid hydrogen is moved from a storage tank to an external tank via a transfer line. By employingDynamical Model of Rocket Propellant Loading with Liquid Hydrogen Viatcheslav V. Osipov MCT, Inc­evaporation of hydrogen, pressurization of the tanks, and liquid hydrogen and hydrogen vaporflows inthe presence

  2. Open problem: Dynamic Relational Models for Improved Hazardous Weather Prediction

    E-Print Network [OSTI]

    McGovern, Amy

    Open problem: Dynamic Relational Models for Improved Hazardous Weather Prediction Amy McGovern1 dis- covery methods for use on mesoscale weather data. Severe weather phenomena such as tornados, thun, current techniques for predicting severe weather are tied to specific characteristics of the radar systems

  3. ZAMM Z. Angew. Math. Mech. 90, No. 3, 241 256 (2010) / DOI 10.1002/zamm.200900314 Dynamic materials with formation of clots: optimal mass transport

    E-Print Network [OSTI]

    Weekes, Suzanne L.

    2010-01-01

    materials with formation of clots: optimal mass transport in one spatial dimension without takeover K. A Key words Dynamic materials, clots, no takeover transport. The concept of dynamic materials (DM 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1 Introduction Heterogeneous material structures

  4. Gauge turbulence, topological defect dynamics, and condensation in Higgs models

    SciTech Connect (OSTI)

    Gasenzer, Thomas; McLerran, Larry; Pawlowski, Jan M.; Sexty, Dénes

    2014-07-28

    The real-time dynamics of topological defects and turbulent configurations of gauge fields for electric and magnetic confinement are studied numerically within a 2+1D Abelian Higgs model. It is shown that confinement is appearing in such systems equilibrating after a strong initial quench such as the overpopulation of the infrared modes. While the final equilibrium state does not support confinement, metastable vortex defect configurations appearing in the gauge field are found to be closely related to the appearance of physically observable confined electric and magnetic charges. These phenomena are seen to be intimately related to the approach of a non-thermal fixed point of the far-from-equilibrium dynamical evolution, signaled by universal scaling in the gauge-invariant correlation function of the Higgs field. Even when the parameters of the Higgs action do not support condensate formation in the vacuum, during this approach, transient Higgs condensation is observed. We discuss implications of these results for the far-from-equilibrium dynamics of Yang–Mills fields and potential mechanisms of how confinement and condensation in non-Abelian gauge fields can be understood in terms of the dynamics of Higgs models. These suggest that there is an interesting new class of dynamics of strong coherent turbulent gauge fields with condensates.

  5. Gauge turbulence, topological defect dynamics, and condensation in Higgs models

    SciTech Connect (OSTI)

    Gasenzer, Thomas [Heidelberg Univ. (Germany). Inst. for Theoretische Physik; GSI-Darmstadt (Germany). ExtreMe Matter Inst. (EMMI); McLerran, Larry [Brookhaven National Lab. (BNL), Upton, NY (United States). RIKEN Research Center and Physics Dept.; China Central Normal Univ., Wuhan (China). Physics Dept.; Pawlowski, Jan M. [Heidelberg Univ. (Germany). Inst. for Theoretische Physik; GSI-Darmstadt (Germany). ExtreMe Matter Inst. (EMMI); Sexty, Dénes [Heidelberg Univ. (Germany). Inst. for Theoretische Physik; GSI-Darmstadt (Germany). ExtreMe Matter Inst. (EMMI)

    2014-10-01

    The real-time dynamics of topological defects and turbulent configurations of gauge fields for electric and magnetic confinement are studied numerically within a 2+1D Abelian Higgs model. It is shown that confinement is appearing in such systems equilibrating after a strong initial quench such as the overpopulation of the infrared modes. While the final equilibrium state does not support confinement, metastable vortex defect configurations appearing in the gauge field are found to be closely related to the appearance of physically observable confined electric and magnetic charges. These phenomena are seen to be intimately related to the approach of a non-thermal fixed point of the far-from-equilibrium dynamical evolution, signaled by universal scaling in the gauge-invariant correlation function of the Higgs field. Even when the parameters of the Higgs action do not support condensate formation in the vacuum, during this approach, transient Higgs condensation is observed. We discuss implications of these results for the far-from-equilibrium dynamics of Yang–Mills fields and potential mechanisms of how confinement and condensation in non-Abelian gauge fields can be understood in terms of the dynamics of Higgs models. These suggest that there is an interesting new class of dynamics of strong coherent turbulent gauge fields with condensates.

  6. Gauge turbulence, topological defect dynamics, and condensation in Higgs models

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gasenzer, Thomas; McLerran, Larry; Pawlowski, Jan M.; Sexty, Dénes

    2014-07-28

    The real-time dynamics of topological defects and turbulent configurations of gauge fields for electric and magnetic confinement are studied numerically within a 2+1D Abelian Higgs model. It is shown that confinement is appearing in such systems equilibrating after a strong initial quench such as the overpopulation of the infrared modes. While the final equilibrium state does not support confinement, metastable vortex defect configurations appearing in the gauge field are found to be closely related to the appearance of physically observable confined electric and magnetic charges. These phenomena are seen to be intimately related to the approach of a non-thermal fixedmore »point of the far-from-equilibrium dynamical evolution, signaled by universal scaling in the gauge-invariant correlation function of the Higgs field. Even when the parameters of the Higgs action do not support condensate formation in the vacuum, during this approach, transient Higgs condensation is observed. We discuss implications of these results for the far-from-equilibrium dynamics of Yang–Mills fields and potential mechanisms of how confinement and condensation in non-Abelian gauge fields can be understood in terms of the dynamics of Higgs models. These suggest that there is an interesting new class of dynamics of strong coherent turbulent gauge fields with condensates.« less

  7. Constraining climate model properties using optimal fingerprint detection methods

    E-Print Network [OSTI]

    Forest, Chris Eliot.; Allen, Myles R.; Sokolov, Andrei P.; Stone, Peter H.

    We present a method for constraining key properties of the climate system that are important for climate prediction (climate sensitivity and rate of heat penetration into the deep ocean) by comparing a model's response to ...

  8. Recent developments in DYNSUB: New models, code optimization and parallelization

    SciTech Connect (OSTI)

    Daeubler, M.; Trost, N.; Jimenez, J.; Sanchez, V. [Karlsruhe Institute of Technology, Institute for Neutron Physics and Reactor Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2013-07-01

    DYNSUB is a high-fidelity coupled code system consisting of the reactor simulator DYN3D and the sub-channel code SUBCHANFLOW. It describes nuclear reactor core behavior with pin-by-pin resolution for both steady-state and transient scenarios. In the course of the coupled code system's active development, super-homogenization (SPH) and generalized equivalence theory (GET) discontinuity factors may be computed with and employed in DYNSUB to compensate pin level homogenization errors. Because of the largely increased numerical problem size for pin-by-pin simulations, DYNSUB has bene fitted from HPC techniques to improve its numerical performance. DYNSUB's coupling scheme has been structurally revised. Computational bottlenecks have been identified and parallelized for shared memory systems using OpenMP. Comparing the elapsed time for simulating a PWR core with one-eighth symmetry under hot zero power conditions applying the original and the optimized DYNSUB using 8 cores, overall speed up factors greater than 10 have been observed. The corresponding reduction in execution time enables a routine application of DYNSUB to study pin level safety parameters for engineering sized cases in a scientific environment. (authors)

  9. Title: Optimal Replacement in the Proportional Hazards Model with semi-Markovian Covariate Process and Continuous Monitoring

    E-Print Network [OSTI]

    Ryan, Sarah M.

    Process and Continuous Monitoring Index terms--Optimal replacement, proportional hazards model, semi1 Title: Optimal Replacement in the Proportional Hazards Model with semi-Markovian Covariate replacement problem for general deteriorating systems in the proportional hazards model with a semi

  10. Model-based simultaneous optimization of multiple design parameters for lithium-ion batteries for maximization of energy density

    E-Print Network [OSTI]

    Subramanian, Venkat

    Model-based simultaneous optimization of multiple design parameters for lithium-ion batteries Keywords: Lithium-ion batteries Model-based design Optimization Physics based reformulated model a b s t r for porous electrodes that are commonly used in advanced batteries such as lithium-ion systems. The approach

  11. On the modelling of spur and helical gear dynamic behaviour

    E-Print Network [OSTI]

    Velex, Philippe

    2012-01-01

    This chapter is aimed at introducing the fundamentals of spur and helical gear dynamics. Using three-dimensional lumped models and a thin-slice approach for mesh elasticity, the general equations of motion for single-stage spur or helical gears are presented. Some particular cases including the classic one degree-of-freedom model are examined in order to introduce and illustrate the basic phenomena. The interest of the concept of transmission errors is analysed and a number of practical considerations are deduced. Emphasis is deliberately placed on analytical results which, although approximate, allow a clearer understanding of gear dynamics than that provided by extensive numerical simulations. Some extensions towards continuous models are presented.

  12. Mathematical Modeling of Microbial Community Dynamics: A Methodological Review

    SciTech Connect (OSTI)

    Song, Hyun-Seob; Cannon, William R.; Beliaev, Alex S.; Konopka, Allan

    2014-10-17

    Microorganisms in nature form diverse communities that dynamically change in structure and function in response to environmental variations. As a complex adaptive system, microbial communities show higher-order properties that are not present in individual microbes, but arise from their interactions. Predictive mathematical models not only help to understand the underlying principles of the dynamics and emergent properties of natural and synthetic microbial communities, but also provide key knowledge required for engineering them. In this article, we provide an overview of mathematical tools that include not only current mainstream approaches, but also less traditional approaches that, in our opinion, can be potentially useful. We discuss a broad range of methods ranging from low-resolution supra-organismal to high-resolution individual-based modeling. Particularly, we highlight the integrative approaches that synergistically combine disparate methods. In conclusion, we provide our outlook for the key aspects that should be further developed to move microbial community modeling towards greater predictive power.

  13. Gaussian Process Model for Collision Dynamics of Complex Molecules

    E-Print Network [OSTI]

    Cui, Jie

    2015-01-01

    We show that a Gaussian Process model can be combined with a small number of scattering calculations to provide an accurate multi-dimensional dependence of scattering observables on the experimentally controllable parameters (such as the collision energy, temperature or external fields) as well as the potential energy surface parameters. This can be used for solving the inverse scattering problem, the prediction of collision properties of a specific molecular system based on the information for another molecule, the efficient calculation of thermally averaged observables and for reducing the error of the molecular dynamics calculations by averaging over the potential energy surface variations. We show that, trained by a combination of classical and quantum dynamics calculations, the model provides an accurate description of the scattering cross sections, even near scattering resonances. In this case, the classical calculations stabilize the model against uncertainties arising from wildly varying correlations ...

  14. Biomass Scenario Model

    SciTech Connect (OSTI)

    2015-09-01

    The Biomass Scenario Model (BSM) is a unique, carefully validated, state-of-the-art dynamic model of the domestic biofuels supply chain which explicitly focuses on policy issues, their feasibility, and potential side effects. It integrates resource availability, physical/technological/economic constraints, behavior, and policy. The model uses a system dynamics simulation (not optimization) to model dynamic interactions across the supply chain.

  15. Optimization of the Dynamic Aperture for SPEAR3 Low-Emittance...

    Office of Scientific and Technical Information (OSTI)

    require a damping wiggler. There is a smaller dynamic aperture for the lower emittance optics due to a stronger nonlinearity. Elegant based Multi-Objective Genetic Algorithm (MOGA)...

  16. Sensitivity analysis of a dynamic model for submerged arc silicon furnaces.

    E-Print Network [OSTI]

    Foss, Bjarne A.

    Sensitivity analysis of a dynamic model for submerged arc silicon furnaces. B. F. Lund1 , B. A for a dynamic model of submerged arc silicon furnaces. The model we study, called "Simod", was developed updating a nonlinear, dynamic model of a silicon furnace. We have identified a parameter set that has

  17. Model for dynamic self-assembled magnetic surface structures.

    SciTech Connect (OSTI)

    Belkin, M.; Glatz, A.; Snezhko, A.; Aranson, I. S.; Materials Science Division; Northwestern Univ.

    2010-07-07

    We propose a first-principles model for the dynamic self-assembly of magnetic structures at a water-air interface reported in earlier experiments. The model is based on the Navier-Stokes equation for liquids in shallow water approximation coupled to Newton equations for interacting magnetic particles suspended at a water-air interface. The model reproduces most of the observed phenomenology, including spontaneous formation of magnetic snakelike structures, generation of large-scale vortex flows, complex ferromagnetic-antiferromagnetic ordering of the snake, and self-propulsion of bead-snake hybrids.

  18. Dynamics of chains with nonmonotone stressstrain relations. 1. Model and Numerical Experiments. \\Lambda

    E-Print Network [OSTI]

    Cherkaev, Andrej

    follows from the optimality requirement, see e.g. [13]. These problems involving complicated materials are in many respects similar to struc­ tural optimization. In both cases, one deals with several materials. of Phys. Mech. Solids 1 #12; Abstract We discuss the dynamical processes in the materials with non

  19. Design of an Electron Gun using Computer Optimization

    E-Print Network [OSTI]

    Design of an Electron Gun using Computer Optimization B. M. Lewis H. T. Tran Department geometry of the system. This optimization framework, to be considered in the context of electron guns the methods of shape optimization to design the cathode of an electron gun. The dynamical equations modeling

  20. Modeling an optical magnetometer with electronic circuits Analysis and optimization

    E-Print Network [OSTI]

    , and bandwidths of the sensors, as well as their different sizes, prices, and maintenance costs [1]. Currently 6 3.2 Model verification 7 3.3 Different detection scheme in self-oscillation mode 8 3.3.1 Pump-probe arrangement with balanced polarimeter 8 3.3.2 Pump-probe arrangement with nearly-crossed polarizer 9 3

  1. Modeling and optimization of a chiller plant Xiupeng Wei*

    E-Print Network [OSTI]

    Kusiak, Andrew

    . The chillers have varying energy efficiency. Since the chiller plant model derived from data-driven approach of chillers, cooling towers, pumps and chilled water storage tanks. It is frequently used to air conditioning was found and controlled to reduce fluc- tuation in chiller efficiency in different operating conditions

  2. Correlations, Competition, and Optimality: Modelling the Development of

    E-Print Network [OSTI]

    Goodhill, Geoffrey J.

    both qualitative and quantitative comparisons with the performance of an algorithm based on the self not satisfactorily address both of these phenomena simultaneously. In this thesis we discuss in detail several models was a great source of inspiration and encouragement to me throughout the thesis, and I am particularly

  3. SUMMARY FOR POLICYMAKERS Modeling Optimal Transition Pathways to a Low

    E-Print Network [OSTI]

    California at Davis, University of

    of California Energy and Climate Policies 2 capture and sequestration or increased supplies of wind and solar and the social, environmental and economic aspects of major transformations. Energy models such as CA and sequestration (CCS). Elastic demand scenarios are also examined to reflect more realistic consumers' demand

  4. Evolutionary dynamic optimization: A survey of the state of the art

    E-Print Network [OSTI]

    2012-04-09

    in dynamic environments due to their inspiration from natural self-organized sys- ... It is noticeable that in many EDO studies, the terms “dynamic problems/time-. 22 ...... 1151 knapsack problem. In [161], Branke et al. further analyzed the role of

  5. Deep ACS Imaging in the Globular Cluster NGC6397: Dynamical Models

    E-Print Network [OSTI]

    Jarrod R. Hurley; Michael M. Shara; Harvey B. Richer; Ivan R. King; D. Saul Davis; Jason S. Kalirai; Brad M. S. Hansen; Aaron Dotter; Jay Anderson; Gregory G. Fahlman; R. Michael Rich

    2008-02-28

    We present N-body models to complement deep imaging of the metal-poor core-collapsed cluster NGC6397 obtained with the Hubble Space Telescope. All simulations include stellar and binary evolution in-step with the stellar dynamics and account for the tidal field of the Galaxy. We focus on the results of a simulation that began with 100000 objects (stars and binaries), 5% primordial binaries and Population II metallicity. After 16 Gyr of evolution the model cluster has about 20% of the stars remaining and has reached core-collapse. We compare the color-magnitude diagrams of the model at this age for the central region and an outer region corresponding to the observed field of NGC6397 (about 2-3 half-light radii from the cluster centre). This demonstrates that the white dwarf population in the outer region has suffered little modification from dynamical processes - contamination of the luminosity function by binaries and white dwarfs with non-standard evolution histories is minimal and should not significantly affect measurement of the cluster age. We also show that the binary fraction of main-sequence stars observed in the NGC6397 field can be taken as representative of the primordial binary fraction of the cluster. For the mass function of the main-sequence stars we find that although this has been altered significantly by dynamics over the cluster lifetime, especially in the central and outer regions, that the position of the observed field is close to optimal for recovering the initial mass function of the cluster stars (below the current turn-off mass). More generally we look at how the mass function changes with radius in a dynamically evolved stellar cluster and suggest where the best radial position to observe the initial mass function is for clusters of any age.

  6. Model of a deterministic detector and dynamical decoherence

    SciTech Connect (OSTI)

    Lee, Jae Weon; Shepelyansky, Dima L. [Laboratoire de Physique Theorique, UMR 5152 du CNRS, Univ. P. Sabatier, 31062 Toulouse Cedex 4 (France); Averin, Dmitri V. [Department of Physics, University of Stony Brook, SUNY, Stony Brook, New York 11794 (United States); Benenti, Giuliano [Center for Nonlinear and Complex Systems, Universita degli Studi dell'Insubria and Istituto Nazionale per la Fisica della Materia, Unita di Como, Via Valleggio 11, 22100 Como (Italy)

    2005-07-15

    We discuss a deterministic model of detector coupled to a two-level system (a qubit). The detector is a quasiclassical object whose dynamics is described by the kicked rotator Hamiltonian. We show that in the regime of quantum chaos the detector acts as a chaotic bath and induces decoherence of the qubit. We discuss the dephasing and relaxation rates and demonstrate that the main features of single-qubit decoherence due to a heat bath can be reproduced by our fully deterministic dynamical model. Moreover, we show that, for strong enough qubit-detector coupling, the dephasing rate is given by the rate of exponential instability of the detector's dynamics, that is, by the Lyapunov exponent of classical motion. Finally, we discuss the measurement in the regimes of strong and weak qubit-detector coupling. For the case of strong coupling the detector performs a measurement of the up/down state of the qubit. In the case of weak coupling, due to chaos, the dynamical evolution of the detector is strongly sensitive to the state of the qubit. However, in this case it is unclear how to extract a signal from any measurement with a coarse-graining in the phase space on a size much larger than the Planck cell.

  7. Multi-resolution modeling of the dynamic loading of metal matrix...

    Office of Scientific and Technical Information (OSTI)

    Multi-resolution modeling of the dynamic loading of metal matrix composites. Citation Details In-Document Search Title: Multi-resolution modeling of the dynamic loading of metal...

  8. Modeling and Optimization of Next Generation Feedstock Development for Chemical Process

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    1929, 2011 #12;Motivation Energy Consumption by Manufacturing Industry 20061Industry, 20061 Primary for CPI · Utilize sun-light energy as carbon- based molecules · Renewable · Reduced CO2 emissions, USA PanAmerican Advanced Studies Institute Process Modeling and Optimization for Energy

  9. Keller's model Variable energy recreation Bounding the derivative of f Optimization of running strategies based on

    E-Print Network [OSTI]

    Boyer, Edmond

    strategies based on anaerobic energy and variations of velocity J. Fr´ed´eric Bonnans Inria-Saclay and CMAP of running strategies hal-01024231,version1-15Jul2014 #12;Keller's model Variable energy recreation Bounding.F. Bonnans, Optimization of running strategies based on anaerobic energy and variations of velocity. SIAM J

  10. A REAL OPTIONS OPTIMIZATION MODEL TO MEET AVAILABILITY REQUIREMENTS FOR OFFSHORE WIND TURBINES

    E-Print Network [OSTI]

    Sandborn, Peter

    1 A REAL OPTIONS OPTIMIZATION MODEL TO MEET AVAILABILITY REQUIREMENTS FOR OFFSHORE WIND TURBINES wind farm with prognostic capabilities. Alternative energy sources such as offshore wind turbines-based maintenance. This is especially important for offshore wind farms that require non- traditional resources

  11. Journal of Power Sources 142 (2005) 184193 Modeling and optimization of catalytic partial oxidation

    E-Print Network [OSTI]

    Daraio, Chiara

    2005-01-01

    of a micro-reformer for a fuel cell unit based on catalytic partial oxidation using a systematic numerical is around 80% is identified. © 2004 Elsevier B.V. All rights reserved. Keywords: Catalytic partial oxidationJournal of Power Sources 142 (2005) 184­193 Modeling and optimization of catalytic partial

  12. Modelling and Design Optimization of Low Speed Fuel Cell Hybrid Electric Vehicles

    E-Print Network [OSTI]

    Victoria, University of

    Modelling and Design Optimization of Low Speed Fuel Cell Hybrid Electric Vehicles by Matthew Blair of emissions to global climate change. Although electric cars and buses have been the focus of much of electric and utility purposes in many countries. In order to explore the viability of fuel cell - battery hybrid

  13. Optimal Perturbations in the Eady Model: Resonance versus PV Unshielding H. DE VRIES

    E-Print Network [OSTI]

    de Vries, Hylke

    Optimal Perturbations in the Eady Model: Resonance versus PV Unshielding H. DE VRIES Institute August 2004) ABSTRACT Using a nonmodal decomposition technique based on the potential vorticity (PV, such that the initial surface potential temperature (PT) is zero. These nonmodal structures are used as PV building

  14. Stochastic Modeling and Optimization for Robust Power Management in a Partially Observable System

    E-Print Network [OSTI]

    Qiu, Qinru

    -of-the- art system modules are capable of trading power for performance or being put into sleep or low powerStochastic Modeling and Optimization for Robust Power Management in a Partially Observable System As the hardware and software complexity grows, it is unlikely for the power management hardware/software to have

  15. Economic Nonlinear Model Predictive Control for the Optimization of Gas Pipeline Networks

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    Compressor 4 Commercial Industry Power Plant LDC 3 Suppliers, 12 Demand nodes, 5 Compressors Sinusoidal Flowrates Industry: N6,12,13,19,21 Commercial: N30,32,34,35 Power Plant: N4,25 LDC: N23 Pcontract = 500 kEconomic Nonlinear Model Predictive Control for the Optimization of Gas Pipeline Networks EWO

  16. Neural NetworkBased Modeling and Optimization for Effective Vehicle Emission Testing and

    E-Print Network [OSTI]

    Huang, Yinlun

    Introduction Automotive emission of hydrocarbons (HC), carbon monoxide (CO), and nitrogen oxides (NOx) has beenNeural Network­Based Modeling and Optimization for Effective Vehicle Emission Testing and Engine emission testing and engine calibration are the key to achieving emission standards with satisfactory fuel

  17. EESOM: Electrical Energy Sourcing Optimization Model Department of Electrical and Systems Engineering

    E-Print Network [OSTI]

    Fang-Yen, Christopher

    EESOM: Electrical Energy Sourcing Optimization Model Department of Electrical and Systems Sobkiw Dr. John Keenan Project Overview The United States' electrical energy sector faces a set. Questions such as when and where electrical energy is needed and how the resources that fuel its generation

  18. EXTENSIONS TO AN EFFICIENT OPTIMIZATION MODEL FOR LONG-TERM PRODUCTION PLANNING 1 Introduction

    E-Print Network [OSTI]

    to the footwall. Once started, mining restrictions require continuous production of the blocks within a machine three raw ore products used to supply four ore post- processing plants, or mills. Phosphorus is the mainEXTENSIONS TO AN EFFICIENT OPTIMIZATION MODEL FOR LONG-TERM PRODUCTION PLANNING 1 Introduction LKAB

  19. Optimizing Computations in Weather and Climate Prediction Models* F. BAER, BANGLIN ZHANG, AND BING ZHANG

    E-Print Network [OSTI]

    Baer, Ferdinand

    Optimizing Computations in Weather and Climate Prediction Models* F. BAER, BANGLIN ZHANG, AND BING scenarios for many time scales, more computer power than is currently available will be needed. One and sometimes with a biosphere included, are very complex and require so much computing power on available

  20. Modeling and Optimizing Hypertextual Search Engines Based on the Reasearch of Larry Page and Sergey Brin

    E-Print Network [OSTI]

    Wu, Xindong

    Engines April 15, 2009 7 / 57 #12;Introduction - Section II - Outline Terms and Definitions Brief Search' or displayed back to the user in hypertextual format. mek (UVM) Search Engines April 15, 2009 9 / 57 #12;TermsModeling and Optimizing Hypertextual Search Engines Based on the Reasearch of Larry Page and Sergey

  1. Modeling, Optimization and Control of Rotary Traveling-Wave Cheng Zhuo, Huafeng Zhang, Rupak Samanta1

    E-Print Network [OSTI]

    Hu, Jiang

    Modeling, Optimization and Control of Rotary Traveling-Wave Oscillator Cheng Zhuo, Huafeng Zhang, Rupak Samanta1 , Jiang Hu2 , Kangsheng Chen Department of Information Science & Electronic Engineering, Zhejiang University, Hangzhou, 310027, China 1,2 Department of Electrical and Computer Engineering, Texas A

  2. Dynamic ModelingDynamic Modeling the Electric Power Networkthe Electric Power Network

    E-Print Network [OSTI]

    Oro, Daniel

    at the National Energy Modeling System/Annual Energy Outlook Conference, Washington, DC, March 10, 2003] #12

  3. Hybrid Model for Building Performance Diagnosis and Optimal Control 

    E-Print Network [OSTI]

    Wang, S.; Xu, X.

    2003-01-01

    S. (1983). Raising the open U value by passive means. Proc. 8th Nat. Passive Solar Conf. Glorieta, NM, pp.839-842. Bahai H. and Esat I.I. (1994). A hybrid model for analysis of complex stress distribution in threaded connectors. Computers... Research Centre of Finland. Kalogirou SA, Neocleous CC and Schizas CN. (1997). Heating load estimation using artificial neural networks. In: Proc. CLIMA 2000 Conf., Brussels (Belgium). Klein S.A., Beckman W.A. et al. (1994). TRNSYS-A Transient System...

  4. On preparation of viscous pore fluids for dynamic centrifuge modelling

    E-Print Network [OSTI]

    Adamidis, O.; Madabhushi, S. P. G.

    2014-11-21

    upon cooling. Gelation temperatures for METHOCEL F50 are well above the expected range of temperatures in dynamic centrifuge modelling [Dow, 2002]. As a result, the gelation process is not consid- ered in this study. Measurements of viscosity... + e e · ki (24) where k is the coefficient of permeability and i is the hydraulic gradient. Since an upper estimate for shearing rate is sought after, the critical hydraulic gradient, for which the seepage forces become equal to the submerged weight...

  5. Introducing a new 3D dynamical model for barred galaxies

    E-Print Network [OSTI]

    Jung, Christof

    2015-01-01

    The regular or chaotic dynamics of an analytical realistic three dimensional model composed of a spherically symmetric central nucleus, a bar and a flat disk is investigated. For describing the properties of the bar we introduce a new simple dynamical model and we explore the influence on the character of orbits of all the involved parameters of it, such as the mass and the scale length of the bar, the major semi-axis and the angular velocity of the bar as well as the energy. Regions of phase space with ordered and chaotic motion are identified in dependence on these parameters and for breaking the rotational symmetry. First we study in detail the dynamics in the invariant plane $z = p_z = 0$ using the Poincar\\'e map as a basic tool and then we study the full 3 dimensional case using the SALI method as principal tool for distinguishing between order and chaos. We also present strong evidence obtained through the numerical simulations that our new bar model can realistically describe the formation and the evol...

  6. Integrated method to create optimal dynamic strategic plans for corporate technology start-ups

    E-Print Network [OSTI]

    Mikati, Samir Omar

    2009-01-01

    This thesis presents an innovative method for evaluating and dynamically planning the development of uncertain technology investments. Its crux centers on a paradigm shift in the way managers assess investments, toward an ...

  7. Dynamic Optimization for Functional Reactive Programming using Generalized Algebraic Data Types

    E-Print Network [OSTI]

    Nilsson, Henrik

    practical purposes. However, this may require quite sophisticated library implementa- tions in the form of a self-optimizing, arrow-based Haskell combinator library. The paper has two aims. Firstly of "pre-composed" primitives that were there mainly for per- formance reasons are no longer needed

  8. Swing Dynamics as Primal-Dual Algorithm for Optimal Load Control

    E-Print Network [OSTI]

    Low, Steven H.

    al. studied the aggregate response character- istics when individual loads are turned on networks, loads can pro- vide flexible, fast responsive, and decentralized sources for frequency regulation and generation-demand balancing, com- plementary to generation control. We consider an optimal load control (OLC

  9. Towards Optimal Solar Tracking: A Dynamic Programming Approach Athanasios Aris Panagopoulos Georgios Chalkiadakis Nicholas R. Jennings

    E-Print Network [OSTI]

    Chalkiadakis, Georgios

    , a large number of photovoltaic systems (PVSs) have been integrated into the electricity grid. A PVS policy: (i) they usually do not consider the forecasted or prevailing weather conditions; even when-optimal trajectories for effective and efficient day-ahead solar tracking, based on weather forecasts coming from on

  10. Temperature-Aware Dynamic Resource Provisioning in a Power-Optimized Datacenter

    E-Print Network [OSTI]

    Pedram, Massoud

    , resource provisioning, energy efficient, power optimization, temperature aware I. INTRODUCTION Cloud-wide power and thermal management (PTM) solutions that improve the energy efficiency of the datacenters and sustainable energy-efficiency curve, this paper seeks to advance the technology of energy-efficient

  11. Optimization of a high-efficiency jet ejector by computational fluid dynamic software 

    E-Print Network [OSTI]

    Watanawanavet, Somsak

    2005-08-29

    Research was performed to optimize high-efficiency jet ejector geometry (Holtzapple, 2001) by varying nozzle diameter ratios from 0.03 to 0.21, and motive velocities from Mach 0.39 to 1.97. The high-efficiency jet ejector was simulated by Fluent...

  12. OPTIMAL HOURAHEAD BIDDING IN THE REALTIME ELECTRICITY MARKET WITH BATTERY STORAGE USING APPROXIMATE DYNAMIC PROGRAMMING

    E-Print Network [OSTI]

    Powell, Warren B.

    OPTIMAL HOUR­AHEAD BIDDING IN THE REAL­TIME ELECTRICITY MARKET WITH BATTERY STORAGE USING of wind and solar energy. Energy arbitrage, the process of buying, storing, and selling electricity System Operator) require that battery storage operators place bids into an hour­ ahead market (although

  13. Wireless Sensor Technology to Optimize the Occupant's Dynamic Demand Pattern Within the Building 

    E-Print Network [OSTI]

    Zeiler, W.; Boxem, G.; Maaijen, R.

    2012-01-01

    behavior of aoocpants of a building. An experimental set-up was developed which was implemented on the 3th floor of one of the offices of Royal Haskoning consulting engineers. This showed the positive effect of using wireless technology to optimize...

  14. Energy Savings Opportunities through Combined Heat and Power Systems Optimization Model Case Studies 

    E-Print Network [OSTI]

    Owaidh, M.

    2015-01-01

    Use Energy Savings Opportunities Through CHP Optimization Models IETC, Jun 2-4 2015 © Copyright 2015, Saudi Aramco. All rights reserved. ESL-IE-15-06-07 Proceedings of the Thrity-Seventh Industrial Energy Technology Conference New Orleans, LA. June 2...-4, 2015 Saudi Aramco: Company General Use Outline: • Introduction – Overview of CHP models – Current Reality • Case Study – Correlations development – Analysis • Conclusion ESL-IE-15-06-07 Proceedings of the Thrity-Seventh Industrial Energy Technology...

  15. MOGO: Model-Oriented Global Optimization of Petascale Applications

    SciTech Connect (OSTI)

    Malony, Allen D.; Shende, Sameer S.

    2012-09-14

    The MOGO project was initiated under in 2008 under the DOE Program Announcement for Software Development Tools for Improved Ease-of-Use on Petascale systems (LAB 08-19). The MOGO team consisted of Oak Ridge National Lab, Argonne National Lab, and the University of Oregon. The overall goal of MOGO was to attack petascale performance analysis by developing a general framework where empirical performance data could be efficiently and accurately compared with performance expectations at various levels of abstraction. This information could then be used to automatically identify and remediate performance problems. MOGO was be based on performance models derived from application knowledge, performance experiments, and symbolic analysis. MOGO was able to make reasonable impact on existing DOE applications and systems. New tools and techniques were developed, which, in turn, were used on important DOE applications on DOE LCF systems to show significant performance improvements.

  16. Nuclear Hybrid Energy System Modeling: RELAP5 Dynamic Coupling Capabilities

    SciTech Connect (OSTI)

    Piyush Sabharwall; Nolan Anderson; Haihua Zhao; Shannon Bragg-Sitton; George Mesina

    2012-09-01

    The nuclear hybrid energy systems (NHES) research team is currently developing a dynamic simulation of an integrated hybrid energy system. A detailed simulation of proposed NHES architectures will allow initial computational demonstration of a tightly coupled NHES to identify key reactor subsystem requirements, identify candidate reactor technologies for a hybrid system, and identify key challenges to operation of the coupled system. This work will provide a baseline for later coupling of design-specific reactor models through industry collaboration. The modeling capability addressed in this report focuses on the reactor subsystem simulation.

  17. From Physics Model to Results: An Optimizing Framework for Cross-Architecture Code Generation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Blazewicz, Marek; Hinder, Ian; Koppelman, David M.; Brandt, Steven R.; Ciznicki, Milosz; Kierzynka, Michal; Löffler, Frank; Schnetter, Erik; Tao, Jian

    2013-01-01

    Starting from a high-level problem description in terms of partial differential equations using abstract tensor notation, theChemoraframework discretizes, optimizes, and generates complete high performance codes for a wide range of compute architectures. Chemora extends the capabilities of Cactus, facilitating the usage of large-scale CPU/GPU systems in an efficient manner for complex applications, without low-level code tuning. Chemora achieves parallelism through MPI and multi-threading, combining OpenMP and CUDA. Optimizations include high-level code transformations, efficient loop traversal strategies, dynamically selected data and instruction cache usage strategies, and JIT compilation of GPU code tailored to the problem characteristics. The discretization is based onmore »higher-order finite differences on multi-block domains. Chemora's capabilities are demonstrated by simulations of black hole collisions. This problem provides an acid test of the framework, as the Einstein equations contain hundreds of variables and thousands of terms.« less

  18. From Physics Model to Results: An Optimizing Framework for Cross-Architecture Code Generation

    E-Print Network [OSTI]

    Marek Blazewicz; Ian Hinder; David M. Koppelman; Steven R. Brandt; Milosz Ciznicki; Michal Kierzynka; Frank Löffler; Erik Schnetter; Jian Tao

    2013-07-24

    Starting from a high-level problem description in terms of partial differential equations using abstract tensor notation, the Chemora framework discretizes, optimizes, and generates complete high performance codes for a wide range of compute architectures. Chemora extends the capabilities of Cactus, facilitating the usage of large-scale CPU/GPU systems in an efficient manner for complex applications, without low-level code tuning. Chemora achieves parallelism through MPI and multi-threading, combining OpenMP and CUDA. Optimizations include high-level code transformations, efficient loop traversal strategies, dynamically selected data and instruction cache usage strategies, and JIT compilation of GPU code tailored to the problem characteristics. The discretization is based on higher-order finite differences on multi-block domains. Chemora's capabilities are demonstrated by simulations of black hole collisions. This problem provides an acid test of the framework, as the Einstein equations contain hundreds of variables and thousands of terms.

  19. Efficient Global Optimization Under Conditions of Noise and Uncertainty A Multi-Model Multi-Grid Windowing Approach

    E-Print Network [OSTI]

    Neumaier, Arnold

    Efficient Global Optimization Under Conditions of Noise and Uncertainty ­ A Multi-Model Multi. By understanding how noise, bias, and topographical inaccuracy in the objective function vary with model resolution into the calculation of the objective function in an optimization problem, producing noise, bias, and topo- graphical

  20. Optimization of a Chilled Water Plant Using a Forward Plant Model 

    E-Print Network [OSTI]

    Zhang, Z.; Turner, W. D.; Chen, Q.; Xu, C.; Deng, S.

    2010-01-01

    of these controls originated from the supervisory control methodology developed by J. E. Braun (1988). Based on model-based ESL-IC-10-10-20 Proceedings of the Tenth International Conference for Enhanced Building Operations, Kuwait, October 26-28, 2010 simulation... for Enhanced Building Operations, Kuwait, October 26-28, 2010 programming (NLP) was more robust and could treat constraints on the state variables directly. Lu et al. (2005b) have presented the optimal set point control for the global optimization problem...

  1. CREATING DYNAMIC EQUIVALENT PV CIRCUIT MODELS WITH IMPEDANCE SPECTROSCOPY FOR ARC FAULT MODELING

    E-Print Network [OSTI]

    CREATING DYNAMIC EQUIVALENT PV CIRCUIT MODELS WITH IMPEDANCE SPECTROSCOPY FOR ARC FAULT MODELING ® (NEC® ) requires new photovoltaic (PV) systems on or penetrating a building to include a listed arc of the arcing frequencies through PV components despite the potential for modules and other PV components

  2. Modelling the e#ects of air pollution on health using Bayesian Dynamic Generalised Linear Models

    E-Print Network [OSTI]

    Bath, University of

    (2004)). Large multi­city studies such as `Air pollution and health: a European approach' (APHEA across a number of US and European cities. Short­term e#ects of air pollution on health are estimatedModelling the e#ects of air pollution on health using Bayesian Dynamic Generalised Linear Models

  3. User Guide for PV Dynamic Model Simulation Written on PSCAD Platform

    SciTech Connect (OSTI)

    Muljadi, E.; Singh, M.; Gevorgian, V.

    2014-11-01

    This document describes the dynamic photovoltaic model developed by the National Renewable Energy Laboratory and is intended as a guide for users of these models.

  4. Use dynamic simulation to model HPU reactor depressuring

    SciTech Connect (OSTI)

    Ernest, J.B.; Depew, C.A. (Fluor Daniel, Inc., Irvine, CA (United States))

    1995-01-01

    Dynamic simulation is the best available method for the analysis of hydroprocessing unit (HPU) depressuring. Depressuring is crucial for the safe operation of hydrocracking and other HPUs with catalysts that have hydrocracking activity. Effective design for depressuring is valuable for all types of HPUs, both grass-roots and revamps. Reactor loop depressuring can set design temperatures and pressures for the reactor effluent cooling train and other equipment and piping in an HPU. Unfortunately, usual methods for determining equipment and piping design conditions during depressuring leave much room for improvement because they poorly account for time-dependent temperature and pressure changes. Dynamic simulation makes it practical to more accurately estimate these transient conditions. The paper discusses depressuring design, including the nature of depressuring, the impact of depressuring on design, and depressuring calculation methods. The author then describes modeling of hydroprocessing unit depressuring by discussing the general and particular correspondence of simulation modules to physical equipment using the base case of total electrical power failure. The special data that is required for dynamic simulation is described and typical simulation results are given. Lastly, the advantages of dynamic simulation are summarized.

  5. Dynamics of Molecular Motors in Reversible Burnt-Bridge Models

    E-Print Network [OSTI]

    Maxim N. Artyomov; Alexander Yu. Morozov; Anatoly B. Kolomeisky

    2009-11-22

    Dynamic properties of molecular motors whose motion is powered by interactions with specific lattice bonds are studied theoretically with the help of discrete-state stochastic "burnt-bridge" models. Molecular motors are depicted as random walkers that can destroy or rebuild periodically distributed weak connections ("bridges") when crossing them, with probabilities $p_1$ and $p_2$ correspondingly. Dynamic properties, such as velocities and dispersions, are obtained in exact and explicit form for arbitrary values of parameters $p_1$ and $p_2$. For the unbiased random walker, reversible burning of the bridges results in a biased directed motion with a dynamic transition observed at very small concentrations of bridges. In the case of backward biased molecular motor its backward velocity is reduced and a reversal of the direction of motion is observed for some range of parameters. It is also found that the dispersion demonstrates a complex, non-monotonic behavior with large fluctuations for some set of parameters. Complex dynamics of the system is discussed by analyzing the behavior of the molecular motors near burned bridges.

  6. Phase-only shaped laser pulses in optimal control theory: Application to indirect photofragmentation dynamics in the weak-field limit

    SciTech Connect (OSTI)

    Shu, Chuan-Cun; Henriksen, Niels E. [Department of Chemistry, Building 207, Technical University of Denmark, DK-2800, Kongens Lyngby (Denmark)

    2012-01-28

    We implement phase-only shaped laser pulses within quantum optimal control theory for laser-molecule interaction. This approach is applied to the indirect photofragmentation dynamics of NaI in the weak-field limit. It is shown that optimized phase-modulated pulses with a fixed frequency distribution can substantially modify transient dissociation probabilities as well as the momentum distribution associated with the relative motion of Na and I.

  7. Modeling and Simulation of the Longitudinal Beam Dynamics - RF Station Interaction in the LHC Rings

    SciTech Connect (OSTI)

    Mastorides, T; Rivetta, C.; Fox, J.D.; Winkle, D.Van; /SLAC; Baudrenghien, P.; Tuckmantel, J.; /CERN

    2008-07-07

    A non-linear time-domain simulation has been developed to study the interaction between longitudinal beam dynamics and RF stations in the LHC rings. The motivation for this tool is to determine optimal LLRF configurations, to study system sensitivity on various parameters, and to define the operational and technology limits. It will be also used to study the effect of RF station noise, impedance, and perturbations on the beam life time and longitudinal emittance. It allows the study of alternative LLRF implementations and control algorithms. The insight and experience gained from our PEP-II simulation is important for this work. In this paper we discuss properties of the simulation tool that will be helpful in analyzing the LHC RF system and its initial results. Partial verification of the model with data taken during the LHC RF station commissioning is presented.

  8. Model Predictive Control-based Optimal Coordination of Distributed Energy Resources

    SciTech Connect (OSTI)

    Mayhorn, Ebony T.; Kalsi, Karanjit; Lian, Jianming; Elizondo, Marcelo A.

    2013-01-07

    Distributed energy resources, such as renewable energy resources (wind, solar), energy storage and demand response, can be used to complement conventional generators. The uncertainty and variability due to high penetration of wind makes reliable system operations and controls challenging, especially in isolated systems. In this paper, an optimal control strategy is proposed to coordinate energy storage and diesel generators to maximize wind penetration while maintaining system economics and normal operation performance. The goals of the optimization problem are to minimize fuel costs and maximize the utilization of wind while considering equipment life of generators and energy storage. Model predictive control (MPC) is used to solve a look-ahead dispatch optimization problem and the performance is compared to an open loop look-ahead dispatch problem. Simulation studies are performed to demonstrate the efficacy of the closed loop MPC in compensating for uncertainties and variability caused in the system.

  9. Model Predictive Control-based Optimal Coordination of Distributed Energy Resources

    SciTech Connect (OSTI)

    Mayhorn, Ebony T.; Kalsi, Karanjit; Lian, Jianming; Elizondo, Marcelo A.

    2013-04-03

    Distributed energy resources, such as renewable energy resources (wind, solar), energy storage and demand response, can be used to complement conventional generators. The uncertainty and variability due to high penetration of wind makes reliable system operations and controls challenging, especially in isolated systems. In this paper, an optimal control strategy is proposed to coordinate energy storage and diesel generators to maximize wind penetration while maintaining system economics and normal operation performance. The goals of the optimization problem are to minimize fuel costs and maximize the utilization of wind while considering equipment life of generators and energy storage. Model predictive control (MPC) is used to solve a look-ahead dispatch optimization problem and the performance is compared to an open loop look-ahead dispatch problem. Simulation studies are performed to demonstrate the efficacy of the closed loop MPC in compensating for uncertainties and variability caused in the system.

  10. Eulerian hydrocode modeling of a dynamic tensile extrusion experiment (u)

    SciTech Connect (OSTI)

    Burkett, Michael W; Clancy, Sean P

    2009-01-01

    Eulerian hydrocode simulations utilizing the Mechanical Threshold Stress flow stress model were performed to provide insight into a dynamic extrusion experiment. The dynamic extrusion response of copper (three different grain sizes) and tantalum spheres were simulated with MESA, an explicit, 2-D Eulerian continuum mechanics hydrocode and compared with experimental data. The experimental data consisted of high-speed images of the extrusion process, recovered extruded samples, and post test metallography. The hydrocode was developed to predict large-strain and high-strain-rate loading problems. Some of the features of the features of MESA include a high-order advection algorithm, a material interface tracking scheme and a van Leer monotonic advection-limiting. The Mechanical Threshold Stress (MTS) model was utilized to evolve the flow stress as a function of strain, strain rate and temperature for copper and tantalum. Plastic strains exceeding 300% were predicted in the extrusion of copper at 400 m/s, while plastic strains exceeding 800% were predicted for Ta. Quantitative comparisons between the predicted and measured deformation topologies and extrusion rate were made. Additionally, predictions of the texture evolution (based upon the deformation rate history and the rigid body rotations experienced by the copper during the extrusion process) were compared with the orientation imaging microscopy measurements. Finally, comparisons between the calculated and measured influence of the initial texture on the dynamic extrusion response of tantalum was performed.

  11. Dynamic mesoscale model of dipolar fluids via fluctuating hydrodynamics

    SciTech Connect (OSTI)

    Persson, Rasmus A. X.; Chu, Jhih-Wei, E-mail: jwchu@nctu.edu.tw [Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu 30068, Taiwan (China); Department of Biological Science and Technology, National Chiao Tung University, Hsinchu 30068, Taiwan (China); Voulgarakis, Nikolaos K. [Department of Mathematics, Washington State University, Richland, Washington 99372 (United States)

    2014-11-07

    Fluctuating hydrodynamics (FHD) is a general framework of mesoscopic modeling and simulation based on conservational laws and constitutive equations of linear and nonlinear responses. However, explicit representation of electrical forces in FHD has yet to appear. In this work, we devised an Ansatz for the dynamics of dipole moment densities that is linked with the Poisson equation of the electrical potential ? in coupling to the other equations of FHD. The resulting ?-FHD equations then serve as a platform for integrating the essential forces, including electrostatics in addition to hydrodynamics, pressure-volume equation of state, surface tension, and solvent-particle interactions that govern the emergent behaviors of molecular systems at an intermediate scale. This unique merit of ?-FHD is illustrated by showing that the water dielectric function and ion hydration free energies in homogeneous and heterogenous systems can be captured accurately via the mesoscopic simulation. Furthermore, we show that the field variables of ?-FHD can be mapped from the trajectory of an all-atom molecular dynamics simulation such that model development and parametrization can be based on the information obtained at a finer-grained scale. With the aforementioned multiscale capabilities and a spatial resolution as high as 5 Å, the ?-FHD equations represent a useful semi-explicit solvent model for the modeling and simulation of complex systems, such as biomolecular machines and nanofluidics.

  12. Multiphase flow in the advanced fluid dynamics model

    SciTech Connect (OSTI)

    Bohl, W.R.; Wilhelm, D.; Berthier, J.; Parker, F.P.; Ichikawa, S.; Goutagny, L.; Ninokata, H.

    1988-01-01

    This paper describes the modeling used in the Advanced Fluid Dynamics Model (AFDM), a computer code to investigate new approaches to simulating severe accidents in fast reactors. The AFDM code has 12 topologies describing what material contacts are possible depending on the presence or absence of a given material in a computational cell, the dominant liquid, and the continuous phase. Single-phase, bubbly, churn-turbulent, cellular, and dispersed flow are permitted for the pool situations modeled. Interfacial areas between the continuous and discontinuous phases are convected to allow some tracking of phenomenological histories. Interfacial areas also are modified by models of nucleation, dynamic forces, turbulence, flashing, coalescence, and mass transfer. Heat transfer generally is treated using engineering correlations. Liquid/vapor phase transitions are handled with a nonequililbrium heat-transfer-limited model, whereas melting and freezing processes are based on equilibrium considerations. The Los Alamos SESAME equation of state (EOS) has been inplemented using densities and temperatures as the independent variables. A summary description of the AFDM numerical algorithm is provided. The AFDM code currently is being debugged and checked out. Two sample three-field calculations also are presented. The first is a three-phase bubble column mixing experiment performed at Argonne National Laboratory; the second is a liquid-liquid mixing experiment performed at Kernforschungszentrum, Karlsruhe, that resulted in rapid vapor production. We conclude that only qualitative comparisons currently are possible for complex multiphase situations. Many further model developments can be pursued, but there are limits because of the lack of a comprehensive theory, the lack of detailed multicomponent experimental data, and the difficulties in keeping the resulting model complexities tractable.

  13. Computational fluid dynamic modeling of fluidized-bed polymerization reactors

    SciTech Connect (OSTI)

    Rokkam, Ram

    2012-11-02

    Polyethylene is one of the most widely used plastics, and over 60 million tons are produced worldwide every year. Polyethylene is obtained by the catalytic polymerization of ethylene in gas and liquid phase reactors. The gas phase processes are more advantageous, and use fluidized-bed reactors for production of polyethylene. Since they operate so close to the melting point of the polymer, agglomeration is an operational concern in all slurry and gas polymerization processes. Electrostatics and hot spot formation are the main factors that contribute to agglomeration in gas-phase processes. Electrostatic charges in gas phase polymerization fluidized bed reactors are known to influence the bed hydrodynamics, particle elutriation, bubble size, bubble shape etc. Accumulation of electrostatic charges in the fluidized-bed can lead to operational issues. In this work a first-principles electrostatic model is developed and coupled with a multi-fluid computational fluid dynamic (CFD) model to understand the effect of electrostatics on the dynamics of a fluidized-bed. The multi-fluid CFD model for gas-particle flow is based on the kinetic theory of granular flows closures. The electrostatic model is developed based on a fixed, size-dependent charge for each type of particle (catalyst, polymer, polymer fines) phase. The combined CFD model is first verified using simple test cases, validated with experiments and applied to a pilot-scale polymerization fluidized-bed reactor. The CFD model reproduced qualitative trends in particle segregation and entrainment due to electrostatic charges observed in experiments. For the scale up of fluidized bed reactor, filtered models are developed and implemented on pilot scale reactor.

  14. Optimizing future imaging survey of galaxies to confront dark energy and modified gravity models

    E-Print Network [OSTI]

    Kazuhiro Yamamoto; David Parkinson; Takashi Hamana; Robert C. Nichol; Yasushi Suto

    2007-07-22

    We consider the extent to which future imaging surveys of galaxies can distinguish between dark energy and modified gravity models for the origin of the cosmic acceleration. Dynamical dark energy models may have similar expansion rates as models of modified gravity, yet predict different growth of structure histories. We parameterize the cosmic expansion by the two parameters, $w_0$ and $w_a$, and the linear growth rate of density fluctuations by Linder's $\\gamma$, independently. Dark energy models generically predict $\\gamma \\approx 0.55$, while the DGP model $\\gamma \\approx 0.68$. To determine if future imaging surveys can constrain $\\gamma$ within 20 percent (or $\\Delta\\gammafuture CMB observations.

  15. Model for Aggregated Water Heater Load Using Dynamic Bayesian Networks

    SciTech Connect (OSTI)

    Vlachopoulou, Maria; Chin, George; Fuller, Jason C.; Lu, Shuai; Kalsi, Karanjit

    2012-07-19

    The transition to the new generation power grid, or “smart grid”, requires novel ways of using and analyzing data collected from the grid infrastructure. Fundamental functionalities like demand response (DR), that the smart grid needs, rely heavily on the ability of the energy providers and distributors to forecast the load behavior of appliances under different DR strategies. This paper presents a new model of aggregated water heater load, based on dynamic Bayesian networks (DBNs). The model has been validated against simulated data from an open source distribution simulation software (GridLAB-D). The results presented in this paper demonstrate that the DBN model accurately tracks the load profile curves of aggregated water heaters under different testing scenarios.

  16. Observations on the Optimality Tolerance in the CAISO 33% RPS Model

    SciTech Connect (OSTI)

    Yao, Y; Meyers, C; Schmidt, A; Smith, S; Streitz, F

    2011-09-22

    In 2008 Governor Schwarzenegger of California issued an executive order requiring that 33 percent of all electricity in the state in the year 2020 should come from renewable resources such as wind, solar, geothermal, biomass, and small hydroelectric facilities. This 33% renewable portfolio standard (RPS) was further codified and signed into law by Governor Brown in 2011. To assess the market impacts of such a requirement, the California Public Utilities Commission (CPUC) initiated a study to quantify the cost, risk, and timing of achieving a 33% RPS by 2020. The California Independent System Operator (CAISO) was contracted to manage this study. The production simulation model used in this study was developed using the PLEXOS software package, which allows energy planners to optimize long-term system planning decisions under a wide variety of system constraints. In this note we describe our observations on varying the optimality tolerance in the CAISO 33% RPS model. In particular, we observe that changing the optimality tolerance from .05% to .5% leads to solutions over 5 times faster, on average, producing very similar solutions with a negligible difference in overall distance from optimality.

  17. ARRAY OPTIMIZATION FOR TIDAL ENERGY EXTRACTION IN A TIDAL CHANNEL – A NUMERICAL MODELING ANALYSIS

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Wang, Taiping; Copping, Andrea

    2014-04-18

    This paper presents an application of a hydrodynamic model to simulate tidal energy extraction in a tidal dominated estuary in the Pacific Northwest coast. A series of numerical experiments were carried out to simulate tidal energy extraction with different turbine array configurations, including location, spacing and array size. Preliminary model results suggest that array optimization for tidal energy extraction in a real-world site is a very complex process that requires consideration of multiple factors. Numerical models can be used effectively to assist turbine siting and array arrangement in a tidal turbine farm for tidal energy extraction.

  18. Combining multi-objective optimization and bayesian model averaging to calibrate forecast ensembles of soil hydraulic models

    SciTech Connect (OSTI)

    Vrugt, Jasper A; Wohling, Thomas

    2008-01-01

    Most studies in vadose zone hydrology use a single conceptual model for predictive inference and analysis. Focusing on the outcome of a single model is prone to statistical bias and underestimation of uncertainty. In this study, we combine multi-objective optimization and Bayesian Model Averaging (BMA) to generate forecast ensembles of soil hydraulic models. To illustrate our method, we use observed tensiometric pressure head data at three different depths in a layered vadose zone of volcanic origin in New Zealand. A set of seven different soil hydraulic models is calibrated using a multi-objective formulation with three different objective functions that each measure the mismatch between observed and predicted soil water pressure head at one specific depth. The Pareto solution space corresponding to these three objectives is estimated with AMALGAM, and used to generate four different model ensembles. These ensembles are post-processed with BMA and used for predictive analysis and uncertainty estimation. Our most important conclusions for the vadose zone under consideration are: (1) the mean BMA forecast exhibits similar predictive capabilities as the best individual performing soil hydraulic model, (2) the size of the BMA uncertainty ranges increase with increasing depth and dryness in the soil profile, (3) the best performing ensemble corresponds to the compromise (or balanced) solution of the three-objective Pareto surface, and (4) the combined multi-objective optimization and BMA framework proposed in this paper is very useful to generate forecast ensembles of soil hydraulic models.

  19. RUMD: A general purpose molecular dynamics package optimized to utilize GPU hardware down to a few thousand particles

    E-Print Network [OSTI]

    Bailey, Nicholas P; Hansen, Jesper Schmidt; Veldhorst, Arno A; Bøhling, Lasse; Lemarchand, Claire A; Olsen, Andreas E; Bacher, Andreas K; Larsen, Heine; Dyre, Jeppe C; Schrøder, Thomas B

    2015-01-01

    RUMD is a general purpose, high-performance molecular dynamics (MD) simulation package running on graphical processing units (GPU's). RUMD addresses the challenge of utilizing the many-core nature of modern GPU hardware when simulating small to medium system sizes (roughly from a few thousand up to hundred thousand particles). It has a performance that is comparable to other GPU-MD codes at large system sizes and substantially better at smaller sizes.RUMD is open-source and consists of a library written in C++ and the CUDA extension to C, an easy-to-use Python interface, and a set of tools for set-up and post-simulation data analysis. The paper describes RUMD's main features, optimizations and performance benchmarks.

  20. Impact of noise on a dynamical system: prediction and uncertainties from a swarm-optimized neural network

    E-Print Network [OSTI]

    López-Caraballo, C H; Salfate, I; Rojas, P; Rivera, M; Palma-Chilla, L

    2015-01-01

    In this study, an artificial neural network (ANN) based on particle swarm optimization (PSO) was developed for the time series prediction. The hybrid ANN+PSO algorithm was applied on Mackey--Glass chaotic time series in the short-term $x(t+6)$. The performance prediction was evaluated and compared with another studies available in the literature. Also, we presented properties of the dynamical system via the study of chaotic behaviour obtained from the predicted time series. Next, the hybrid ANN+PSO algorithm was complemented with a Gaussian stochastic procedure (called {\\it stochastic} hybrid ANN+PSO) in order to obtain a new estimator of the predictions, which also allowed us to compute uncertainties of predictions for noisy Mackey--Glass chaotic time series. Thus, we studied the impact of noise for several cases with a white noise level ($\\sigma_{N}$) from 0.01 to 0.1.

  1. Optimization of the Dynamic Aperture for SPEAR3 Low-Emittance Upgrade

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeeding access to(Conference) | SciTech Connect Optimization of the

  2. Optimization of the Dynamic Aperture for SPEAR3 Low-Emittance Upgrade

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeeding access to(Conference) | SciTech Connect Optimization of

  3. COLLABORATIVE RESEARCH: CONTINUOUS DYNAMIC GRID ADAPTATION IN A GLOBAL ATMOSPHERIC MODEL: APPLICATION AND REFINEMENT

    SciTech Connect (OSTI)

    Gutowski, William J.; Prusa, Joseph M.; Smolarkiewicz, Piotr K.

    2012-05-08

    This project had goals of advancing the performance capabilities of the numerical general circulation model EULAG and using it to produce a fully operational atmospheric global climate model (AGCM) that can employ either static or dynamic grid stretching for targeted phenomena. The resulting AGCM combined EULAG's advanced dynamics core with the "physics" of the NCAR Community Atmospheric Model (CAM). Effort discussed below shows how we improved model performance and tested both EULAG and the coupled CAM-EULAG in several ways to demonstrate the grid stretching and ability to simulate very well a wide range of scales, that is, multi-scale capability. We leveraged our effort through interaction with an international EULAG community that has collectively developed new features and applications of EULAG, which we exploited for our own work summarized here. Overall, the work contributed to over 40 peer-reviewed publications and over 70 conference/workshop/seminar presentations, many of them invited. 3a. EULAG Advances EULAG is a non-hydrostatic, parallel computational model for all-scale geophysical flows. EULAG's name derives from its two computational options: EULerian (flux form) or semi-LAGrangian (advective form). The model combines nonoscillatory forward-in-time (NFT) numerical algorithms with a robust elliptic Krylov solver. A signature feature of EULAG is that it is formulated in generalized time-dependent curvilinear coordinates. In particular, this enables grid adaptivity. In total, these features give EULAG novel advantages over many existing dynamical cores. For EULAG itself, numerical advances included refining boundary conditions and filters for optimizing model performance in polar regions. We also added flexibility to the model's underlying formulation, allowing it to work with the pseudo-compressible equation set of Durran in addition to EULAG's standard anelastic formulation. Work in collaboration with others also extended the demonstrated range of validity of soundproof models, showing that they are more broadly applicable than some had previously thought. Substantial testing of EULAG included application and extension of the Jablonowski-Williamson baroclinic wave test - an archetype of planetary weather - and further analysis of multi-scale interactions arising from collapse of temperature fronts in both the baroclinic wave test and simulations of the Held-Suarez idealized climate. These analyses revealed properties of atmospheric gravity waves not seen in previous work and further demonstrated the ability of EULAG to simulate realistic behavior over several orders of magnitude of length scales. Additional collaborative work enhanced capability for modeling atmospheric flows with adaptive moving meshes and demonstrated the ability of EULAG to move into petascale computing. 3b. CAM-EULAG Advances We have developed CAM-EULAG in collaboration with former project postdoc, now University of Cape Town Assistant Professor, Babatunde Abiodun. Initial study documented good model performance in aqua-planet simulations. In particular, we showed that the grid adaptivity (stretching) implemented in CAM-EULAG allows higher resolution in selected regions without causing anomalous behavior such as spurious wave reflection. We then used the stretched-grid version to analyze simulated extreme precipitation events in West Africa, comparing the precipitation and event environment with observed behavior. The model simulates fairly well the spatial scale and the interannual and intraseasonal variability of the extreme events, although its extreme precipitation intensity is weaker than observed. In addition, both observations and the simulations show possible forcing of extreme events by African easterly waves. 3c. Other Contributions Through our collaborations, we have made contributions to a wide range of outcomes. For research focused on terrestrial behavior, these have included (1) upwind schemes for gas dynamics, (2) a nonlinear perspective on the dynamics of the Madden-Julian Oscillation, (3) numerical realism of thermal co

  4. Entanglement dynamics in a model tripartite quantum system

    E-Print Network [OSTI]

    Pradip Laha; B. Sudarsan; S. Lakshmibala; V. Balakrishnan

    2015-09-23

    A system comprising a $\\Lambda$-type or V-type atom interacting with two radiation fields exhibits, during its dynamical evolution, interesting optical phenomena such as electromagnetically-induced transparency (EIT) and a variety of nonclassical effects. Signatures of the latter are seen in the entanglement dynamics of the atomic subsystem and in appropriate field observables. Some of these effects have been experimentally detected, and have even been used to change the nonlinear optical properties of certain atomic media. It is therefore useful to investigate the roles played by specific initial states of the radiation fields, detuning parameters, field nonlinearities and the nature of field-atom couplings on EIT and on the entanglement between subsystems. We investigate these aspects in the framework of a simple model that captures the salient features of such tripartite entangled systems. Entanglement dynamics is shown to be very sensitive to the intensity-dependent atom-field couplings. Unexpected interesting features pertaining to the collapses and revivals of the atomic subsystem von Neumann entropy appear. These features could, in principle, be useful in enabling entanglement.

  5. Dynamic Properties of Molecular Motors in Burnt-Bridge Models

    E-Print Network [OSTI]

    Maxim N. Artyomov; Alexander Yu. Morozov; Ekaterina Pronina; Anatoly B. Kolomeisky

    2007-05-04

    Dynamic properties of molecular motors that fuel their motion by actively interacting with underlying molecular tracks are studied theoretically via discrete-state stochastic ``burnt-bridge'' models. The transport of the particles is viewed as an effective diffusion along one-dimensional lattices with periodically distributed weak links. When an unbiased random walker passes the weak link it can be destroyed (``burned'') with probability p, providing a bias in the motion of the molecular motor. A new theoretical approach that allows one to calculate exactly all dynamic properties of motor proteins, such as velocity and dispersion, at general conditions is presented. It is found that dispersion is a decreasing function of the concentration of bridges, while the dependence of dispersion on the burning probability is more complex. Our calculations also show a gap in dispersion for very low concentrations of weak links which indicates a dynamic phase transition between unbiased and biased diffusion regimes. Theoretical findings are supported by Monte Carlo computer simulations.

  6. A LUMPED-PARAMETER DYNAMIC MODEL OF A THERMAL REGENERATOR FOR FREE-PISTON STIRLING ENGINES

    E-Print Network [OSTI]

    Barth, Eric J.

    A LUMPED-PARAMETER DYNAMIC MODEL OF A THERMAL REGENERATOR FOR FREE-PISTON STIRLING ENGINES Mark the mass flow, piston dynamics, and control volume behavior inside a free-piston Stirling engine. A new model for a Stirling engine thermal regenerator that incorporates a dynamically changing temperature

  7. Polymer dynamics in repton model at large fields Anatoly B. Kolomeisky

    E-Print Network [OSTI]

    Polymer dynamics in repton model at large fields Anatoly B. Kolomeisky Department of Chemistry, Poland Received 22 October 2003; accepted 26 January 2004 Polymer dynamics at large fields in Rubinstein simple exclusion models are used to analyze the reptation dynamics of polymers. It is found

  8. Low-Thrust, High-Accuracy Trajectory Optimization

    E-Print Network [OSTI]

    Ross, IM; Gong, Q; Sekhavat, P

    2007-01-01

    A. E. , Dynamic Optimization, Addison Wesley Longman, Inc. ,M. , “Space Trajectory Optimization and L 1 -Optimal ControlMethods for Trajectory Optimization,” Journal of Guidance,

  9. Parametric Studies and Optimization of Eddy Current Techniques through Computer Modeling

    SciTech Connect (OSTI)

    Todorov, E. I. [EWI, Engineering and NDE, 1250 Arthur E. Adams Dr., Columbus, OH 43221-3585 (United States)

    2007-03-21

    The paper demonstrates the use of computer models for parametric studies and optimization of surface and subsurface eddy current techniques. The study with high-frequency probe investigates the effect of eddy current frequency and probe shape on the detectability of flaws in the steel substrate. The low-frequency sliding probe study addresses the effect of conductivity between the fastener and the hole, frequency and coil separation distance on detectability of flaws in subsurface layers.

  10. A Dynamic Supply-Demand Model for Electricity Prices Manuela Buzoianu

    E-Print Network [OSTI]

    A Dynamic Supply-Demand Model for Electricity Prices Manuela Buzoianu , Anthony E. Brockwell to as a dynamic supply-demand model, to simultaneously capture electricity price and usage time series. This model, and Duane J. Seppi Abstract We introduce a new model for electricity prices, based on the principle

  11. Designability, thermodynamic stability, and dynamics in protein folding: A lattice model study

    E-Print Network [OSTI]

    Levine, Alex J.

    Designability, thermodynamic stability, and dynamics in protein folding: A lattice model study Re October 1998 In the framework of a lattice-model study of protein folding, we investigate the interplay model. Lattice models have been widely used in the study of protein folding dynamics.2­8 The main

  12. An Approximate Inference Approach to Temporal Optimization in Optimal Control

    E-Print Network [OSTI]

    Vijayakumar, Sethu

    ­ Motivation · Stochastic Optimal feedback control (SOFC) is a plausible move- ment generation strategy in goal with non-linear dynamics and non-quadratic costs SOFC law can only be found locally and iteratively, e ­ SOFC Model Random variables we use here: xt state of a plant (joint angles q and velocities q) ut

  13. Optimizing Higher-Order Lagrangian Perturbation Theory for Standard CDM and BSI models

    E-Print Network [OSTI]

    Arno G. Weiss; Stefan Gottloeber; Thomas Buchert

    1995-05-24

    We investigate the performance of Lagrangian perturbation theory up to the second order for two scenarios of cosmological large-scale structure formation, SCDM (standard cold dark matter) and BSI (broken scale invariance). The latter model we study as a representative of COBE-normalized CDM models which fit the small-scale power of galaxy surveys. In this context we optimize the performance of the Lagrangian perturbation schemes by smoothing the small-scale fluctuations in the initial data. The results of the so obtained Lagrangian mappings are computed for a set of COBE-normalized SCDM and BSI initial data of different sizes and at different times. We compare these results against those obtained with a numerical PM-code. We find an excellent performance of the optimized Lagrangian schemes down to scales close to the correlation length. This is explained by the counterintuitive fact that nonlinearities in the model can produce more small-scale power, if initially such power is removed. The optimization scheme can be expressed in a way which is independent of the type of fluctuation spectrum and of the size of the simulations.

  14. Spatially Heterogeneous Dynamics and Dynamic Facilitation in a Model of Viscous Silica Michael Vogel* and Sharon C. Glotzer

    E-Print Network [OSTI]

    Weeks, Eric R.

    this behavior. The mode coupling theory [1] describes many aspects of dynamical behavior at high T is not only relevant in spin models [26], but also in a viscous equilibrium liquid. Finally, we show is still the understanding of the tremen- dous slowing down of molecular dynamics in supercooled liquids

  15. Modeling Temporal Behavior in Large Networks: A Dynamic Mixed-Membership Model

    SciTech Connect (OSTI)

    Rossi, R; Gallagher, B; Neville, J; Henderson, K

    2011-11-11

    Given a large time-evolving network, how can we model and characterize the temporal behaviors of individual nodes (and network states)? How can we model the behavioral transition patterns of nodes? We propose a temporal behavior model that captures the 'roles' of nodes in the graph and how they evolve over time. The proposed dynamic behavioral mixed-membership model (DBMM) is scalable, fully automatic (no user-defined parameters), non-parametric/data-driven (no specific functional form or parameterization), interpretable (identifies explainable patterns), and flexible (applicable to dynamic and streaming networks). Moreover, the interpretable behavioral roles are generalizable, computationally efficient, and natively supports attributes. We applied our model for (a) identifying patterns and trends of nodes and network states based on the temporal behavior, (b) predicting future structural changes, and (c) detecting unusual temporal behavior transitions. We use eight large real-world datasets from different time-evolving settings (dynamic and streaming). In particular, we model the evolving mixed-memberships and the corresponding behavioral transitions of Twitter, Facebook, IP-Traces, Email (University), Internet AS, Enron, Reality, and IMDB. The experiments demonstrate the scalability, flexibility, and effectiveness of our model for identifying interesting patterns, detecting unusual structural transitions, and predicting the future structural changes of the network and individual nodes.

  16. Accurate Component Model Based Optimal Control for Energy Storage Systems in Households with Photovoltaic Modules

    E-Print Network [OSTI]

    Pedram, Massoud

    of the realistic electricity price function and the energy storage capacity limitation, the residential storage--Integrating residential photovoltaic (PV) power generation and energy storage systems into the Smart Grid is an effective a particularly interesting problem with the introduction of dynamic electricity energy pricing models since

  17. Models for Optimization of Energy Consumption of Pumps in a Wastewater Processing Plant

    E-Print Network [OSTI]

    Kusiak, Andrew

    ; Energy consumption; Data collection; Neural networks; Dynamic models; Statics; Water treatment plants in wastewater processing plants usually follow two strategies. One is to upgrade the current sewage sludge treatment process and produce higher quality efflu- ent. The other is to modify or redesign the sludge

  18. Entanglement dynamics for the double Tavis-Cummings model

    E-Print Network [OSTI]

    Zhong-Xiao Man; Yun-Jie Xia; Nguyen Ba An

    2009-02-14

    A double Tavis-Cummings model (DTCM) is developed to simulate the entanglement dynamics of realistic quantum information processing where two entangled atom-pairs $AB$ and $CD$ are distributed in such a way that atoms $AC$ are embedded in a cavity $a$ while $BD$ are located in another remote cavity $b$. The evolutions of different types of initially shared entanglement of atoms are studied under various initial states of cavity fields. The results obtained in the DTCM are compared with that obtained in the double Jaynes-Cummings model (DJCM) [J. Phys. B \\textbf{40}, S45 (2007)] and an interaction strength theory is proposed to explain the parameter domain in which the so-called entanglement sudden death occurs for both the DTCM and DJCM.

  19. FlexDPDP: FlexList-based Optimized Dynamic Provable Data Possession Ertem Esiner, Adilet Kachkeev, Samuel Braunfeld, Alptekin Kupcu, and Oznur Ozkasap

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    FlexDPDP: FlexList-based Optimized Dynamic Provable Data Possession Ertem Esiner, Adilet Kachkeev the integrity of data stored at an untrusted server has become significant. Authenticated Skip Lists and Rank-based an underlying authenticated data structure based on a skip list [49]. A skip list [49] is a tree-like hierar

  20. Fast Protein Folding in the Hydrophobic-hydrophilic Model Within Three-eights of Optimal (Extended Abstract)

    E-Print Network [OSTI]

    Istrail, Sorin

    Fast Protein Folding in the Hydrophobic-hydrophilic Model Within Three-eights of Optimal (Extended for the protein folding problem in the hydrophobic- hydrophilic model, Dill (1985). To our knowledge, our al for this model, Dill (1994). The hydrophobic-hydrophilic model abstracts the dominant force of protein folding

  1. 210 IEEE SIGNAL PROCESSING LETTERS, VOL. 6, NO. 8, AUGUST 1999 Noise Modeling for Nearfield Array Optimization

    E-Print Network [OSTI]

    Abhayapala, Thushara D.

    210 IEEE SIGNAL PROCESSING LETTERS, VOL. 6, NO. 8, AUGUST 1999 Noise Modeling for Nearfield Array spherically isotropic noise model is introduced. The proposed noise model can be utilized effectively to apply. A simple array gain optimization is used to demonstrate the use of the new noise model. Index Terms

  2. Model Based Optimal Sensor Network Design for Condition Monitoring in an IGCC Plant

    SciTech Connect (OSTI)

    Kumar, Rajeeva; Kumar, Aditya; Dai, Dan; Seenumani, Gayathri; Down, John; Lopez, Rodrigo

    2012-12-31

    This report summarizes the achievements and final results of this program. The objective of this program is to develop a general model-based sensor network design methodology and tools to address key issues in the design of an optimal sensor network configuration: the type, location and number of sensors used in a network, for online condition monitoring. In particular, the focus in this work is to develop software tools for optimal sensor placement (OSP) and use these tools to design optimal sensor network configuration for online condition monitoring of gasifier refractory wear and radiant syngas cooler (RSC) fouling. The methodology developed will be applicable to sensing system design for online condition monitoring for broad range of applications. The overall approach consists of (i) defining condition monitoring requirement in terms of OSP and mapping these requirements in mathematical terms for OSP algorithm, (ii) analyzing trade-off of alternate OSP algorithms, down selecting the most relevant ones and developing them for IGCC applications (iii) enhancing the gasifier and RSC models as required by OSP algorithms, (iv) applying the developed OSP algorithm to design the optimal sensor network required for the condition monitoring of an IGCC gasifier refractory and RSC fouling. Two key requirements for OSP for condition monitoring are desired precision for the monitoring variables (e.g. refractory wear) and reliability of the proposed sensor network in the presence of expected sensor failures. The OSP problem is naturally posed within a Kalman filtering approach as an integer programming problem where the key requirements of precision and reliability are imposed as constraints. The optimization is performed over the overall network cost. Based on extensive literature survey two formulations were identified as being relevant to OSP for condition monitoring; one based on LMI formulation and the other being standard INLP formulation. Various algorithms to solve these two formulations were developed and validated. For a given OSP problem the computation efficiency largely depends on the “size” of the problem. Initially a simplified 1-D gasifier model assuming axial and azimuthal symmetry was used to test out various OSP algorithms. Finally these algorithms were used to design the optimal sensor network for condition monitoring of IGCC gasifier refractory wear and RSC fouling. The sensors type and locations obtained as solution to the OSP problem were validated using model based sensing approach. The OSP algorithm has been developed in a modular form and has been packaged as a software tool for OSP design where a designer can explore various OSP design algorithm is a user friendly way. The OSP software tool is implemented in Matlab/Simulink© in-house. The tool also uses few optimization routines that are freely available on World Wide Web. In addition a modular Extended Kalman Filter (EKF) block has also been developed in Matlab/Simulink© which can be utilized for model based sensing of important process variables that are not directly measured through combining the online sensors with model based estimation once the hardware sensor and their locations has been finalized. The OSP algorithm details and the results of applying these algorithms to obtain optimal sensor location for condition monitoring of gasifier refractory wear and RSC fouling profile are summarized in this final report.

  3. An MILP-MINLP decomposition method for the global optimization of a source based model of the

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    and regulatory specifications of products. For example, the economic and operability benefits from optimal crude-oilAn MILP-MINLP decomposition method for the global optimization of a source based model. In this work we present two major contributions for the global solution of the problem. The first one

  4. FODO-Supercell Based Compact Ring Design with Tunable Momentum Compaction and Optimized Dynamic Aperture

    SciTech Connect (OSTI)

    Sun, Yipeng; /SLAC

    2012-05-11

    A storage ring with tunable momentum compaction has the advantage in achieving different RMS bunch length with similar RF capacity, which is potentially useful for many applications, such as linear collider damping ring and pre-damping ring where injected beam has a large energy spread and a large transverse emittance. A tunable bunch length also makes the commissioning and fine tuning easier in manipulating the single bunch instabilities. In this paper, a compact ring design based on a supercell is presented, which achieves a tunable momentum compaction while maintaining a large dynamic aperture.

  5. Optimal Regulation of Heating Systems with Metering Based on Dynamic Simulation 

    E-Print Network [OSTI]

    Zhao, H.; Wang, P.; Zeng, G.; Tian, Y.

    2006-01-01

    The mathematical models of heat networks and heat users are established using the node method. The physical model of a typical room instead of a heat user is used; meanwhile the equation of radiator controlled by thermostat is put forward to compute...

  6. Parameter Estimation of Dynamic Air-conditioning Component Models Using Limited Sensor Data 

    E-Print Network [OSTI]

    Hariharan, Natarajkumar

    2011-08-08

    This thesis presents an approach for identifying critical model parameters in dynamic air-conditioning systems using limited sensor information. The expansion valve model and the compressor model parameters play a crucial ...

  7. DYNAMIC MODELLING OF LIVING ANIONIC SOLUTION POLYMERIZATION OF STYRENE/BUTADIENE/DIVINYLBENZENE

    E-Print Network [OSTI]

    Schittkowski, Klaus

    DYNAMIC MODELLING OF LIVING ANIONIC SOLUTION POLYMERIZATION OF STYRENE/BUTADIENE model for the living anionic solution polymerization of styrene/butadiene/divinylbenzene in a continuous kinetic reactor model for the living anionic solution polymerization of styrene/butadiene

  8. VISION -- A Dynamic Model of the Nuclear Fuel Cycle

    SciTech Connect (OSTI)

    J. J. Jacobson; A. M. Yacout; S. J. Piet; D. E. Shropshire; G. E. Matthern

    2006-02-01

    The Advanced Fuel Cycle Initiative’s (AFCI) fundamental objective is to provide technology options that – if implemented – would enable long-term growth of nuclear power while improving sustainability and energy security. The AFCI organization structure consists of four areas; Systems Analysis, Fuels, Separations and Transmutations. The Systems Analysis Working Group is tasked with bridging the program technical areas and providing the models, tools, and analyses required to assess the feasibility of design and deploy¬ment options and inform key decision makers. An integral part of the Systems Analysis tool set is the development of a system level model that can be used to examine the implications of the different mixes of reactors, implications of fuel reprocessing, impact of deployment technologies, as well as potential “exit” or “off ramp” approaches to phase out technologies, waste management issues and long-term repository needs. The Verifiable Fuel Cycle Simulation Model (VISION) is a computer-based simulation model that allows performing dynamic simulations of fuel cycles to quantify infrastructure requirements and identify key trade-offs between alternatives. VISION is intended to serve as a broad systems analysis and study tool applicable to work conducted as part of the AFCI (including costs estimates) and Generation IV reactor development studies.

  9. THE DYNAMICAL STRUCTURE FACTOR AND CRITICAL BEHAVIOR OF A TRAFFIC FLOW MODEL

    E-Print Network [OSTI]

    Lübeck, Sven

    261 THE DYNAMICAL STRUCTURE FACTOR AND CRITICAL BEHAVIOR OF A TRAFFIC FLOW MODEL L. ROTERS, S. L. The behavior of the model is determined by three parameters, the maximal velocity v max , the noise parameter P of the dynamical structure factor of the Nagel­ Schreckenberg traffic flow model based on the local occupation

  10. Comparing the escape dynamics in tidally limited star cluster models

    E-Print Network [OSTI]

    Euaggelos E. Zotos

    2015-08-21

    The aim of this work is to compare the orbital dynamics in three different models describing the properties of a star cluster rotating around its parent galaxy in a circular orbit. In particular, we use the isochrone and the Hernquist potentials to model the spherically symmetric star cluster and we compare our results with the corresponding ones of a previous work in which the Plummer model was applied for the same purpose. Our analysis takes place both in the configuration $(x,y)$ and in the phase $(x,\\dot{x})$ space in order to elucidate the escape process as well as the overall orbital properties of the tidally limited star cluster. We restrict our investigation into two dimensions and we conduct a thorough numerical analysis distinguishing between ordered and chaotic orbits as well as between trapped and escaping orbits, considering only unbounded motion for several energy levels above the critical escape energy. It is of particular interest to determine the escape basins towards the two exit channels (near the Lagrangian points $L_1$ and $L_2$) and relate them with the corresponding escape times of the orbits.

  11. Comparing the escape dynamics in tidally limited star cluster models

    E-Print Network [OSTI]

    Zotos, Euaggelos E

    2015-01-01

    The aim of this work is to compare the orbital dynamics in three different models describing the properties of a star cluster rotating around its parent galaxy in a circular orbit. In particular, we use the isochrone and the Hernquist potentials to model the spherically symmetric star cluster and we compare our results with the corresponding ones of a previous work in which the Plummer model was applied for the same purpose. Our analysis takes place both in the configuration $(x,y)$ and in the phase $(x,\\dot{x})$ space in order to elucidate the escape process as well as the overall orbital properties of the tidally limited star cluster. We restrict our investigation into two dimensions and we conduct a thorough numerical analysis distinguishing between ordered and chaotic orbits as well as between trapped and escaping orbits, considering only unbounded motion for several energy levels above the critical escape energy. It is of particular interest to determine the escape basins towards the two exit channels (n...

  12. Description of waste pretreatment and interfacing systems dynamic simulation model

    SciTech Connect (OSTI)

    Garbrick, D.J.; Zimmerman, B.D.

    1995-05-01

    The Waste Pretreatment and Interfacing Systems Dynamic Simulation Model was created to investigate the required pretreatment facility processing rates for both high level and low level waste so that the vitrification of tank waste can be completed according to the milestones defined in the Tri-Party Agreement (TPA). In order to achieve this objective, the processes upstream and downstream of the pretreatment facilities must also be included. The simulation model starts with retrieval of tank waste and ends with vitrification for both low level and high level wastes. This report describes the results of three simulation cases: one based on suggested average facility processing rates, one with facility rates determined so that approximately 6 new DSTs are required, and one with facility rates determined so that approximately no new DSTs are required. It appears, based on the simulation results, that reasonable facility processing rates can be selected so that no new DSTs are required by the TWRS program. However, this conclusion must be viewed with respect to the modeling assumptions, described in detail in the report. Also included in the report, in an appendix, are results of two sensitivity cases: one with glass plant water recycle steams recycled versus not recycled, and one employing the TPA SST retrieval schedule versus a more uniform SST retrieval schedule. Both recycling and retrieval schedule appear to have a significant impact on overall tank usage.

  13. Temperature dependent transport coefficients in a dynamical holographic QCD model

    E-Print Network [OSTI]

    Danning Li; Song He; Mei Huang

    2014-11-19

    We investigate temperature dependent behavior of various transport coefficients in a dynamical holographical QCD model. We show the nontrivial temperature dependent behavior of the transport coefficients, like bulk viscosity, electric conductivity as well as jet quenching parameter, and it is found that all these quantities reveal information of the phase transition. Furthermore, with introducing higher derivative corrections in 5D gravity, the shear viscosity over entropy density ratio also shows a valley around phase transition, and it is found that the shear viscosity over entropy density ratio times the jet quenching over temperature cubic ratio almost remains as a constant above phase transition, and the value is two times larger than the perturbative result in Phys.Rev.Lett.99.192301(2007).

  14. Hydro-dynamical models for the chaotic dripping faucet

    E-Print Network [OSTI]

    P. Coullet; L. Mahadevan; C. S. Riera

    2004-08-20

    We give a hydrodynamical explanation for the chaotic behaviour of a dripping faucet using the results of the stability analysis of a static pendant drop and a proper orthogonal decomposition (POD) of the complete dynamics. We find that the only relevant modes are the two classical normal forms associated with a Saddle-Node-Andronov bifurcation and a Shilnikov homoclinic bifurcation. This allows us to construct a hierarchy of reduced order models including maps and ordinary differential equations which are able to qualitatively explain prior experiments and numerical simulations of the governing partial differential equations and provide an explanation for the complexity in dripping. We also provide a new mechanical analogue for the dripping faucet and a simple rationale for the transition from dripping to jetting modes in the flow from a faucet.

  15. Hydro-dynamical models for the chaotic dripping faucet

    E-Print Network [OSTI]

    Coullet, P; Riera, C S

    2004-01-01

    We give a hydrodynamical explanation for the chaotic behaviour of a dripping faucet using the results of the stability analysis of a static pendant drop and a proper orthogonal decomposition (POD) of the complete dynamics. We find that the only relevant modes are the two classical normal forms associated with a Saddle-Node-Andronov bifurcation and a Shilnikov homoclinic bifurcation. This allows us to construct a hierarchy of reduced order models including maps and ordinary differential equations which are able to qualitatively explain prior experiments and numerical simulations of the governing partial differential equations and provide an explanation for the complexity in dripping. We also provide a new mechanical analogue for the dripping faucet and a simple rationale for the transition from dripping to jetting modes in the flow from a faucet.

  16. EXTENDING THE REALM OF OPTIMIZATION FOR COMPLEX SYSTEMS: UNCERTAINTY, COMPETITION, AND DYNAMICS

    SciTech Connect (OSTI)

    Shanbhag, Uday V; Basar, Tamer; Meyn, Sean; Mehta, Prashant

    2013-10-08

    Research reported addressed these topics: the development of analytical and algorithmic tools for distributed computation of Nash equilibria; synchronization in mean-field oscillator games, with an emphasis on learning and efficiency analysis; questions that combine learning and computation; questions including stochastic and mean-field games; modeling and control in the context of power markets.

  17. Optimal release strategies for biological control agents: an application of stochastic dynamic programming to

    E-Print Network [OSTI]

    Queensland, University of

    of releases), given constraints on time and the number of biocontrol agents available. By modelling within of pests and weeds. Biological control involves introducing natural enemies, biocontrol agents, to help decide what factors might assist the establish- ment of biocontrol agents, although some guidelines do

  18. Emerging disease dynamics in a model coupling within-host and ...

    E-Print Network [OSTI]

    Xiuli Cen

    2014-08-27

    Aug 2, 2014 ... Immunological models consider the within-host dynamics independent of the interactions between hosts (e.g., De Leenheer and Smith, 2003;.

  19. Microscale and mesoscale discrete models for dynamic fracture of structures built of brittle material

    E-Print Network [OSTI]

    Microscale and mesoscale discrete models for dynamic fracture of structures built of brittle are derived either at microscale with random distribution of material properties or at a mesoscale

  20. Quantum Speed Limit and Optimal Control of Many-Boson Dynamics

    E-Print Network [OSTI]

    Ioannis Brouzos; Alexej I. Streltsov; Antonio Negretti; Ressa S. Said; Tommaso Caneva; Simone Montangero; Tommaso Calarco

    2015-05-12

    We extend the concept of quantum speed limit -- the minimal time needed to perform a driven evolution -- to complex interacting many-body systems. We investigate a prototypical many-body system, a bosonic Josephson junction, at increasing levels of complexity: (a) within the two-mode approximation {corresponding to} a nonlinear two-level system, (b) at the mean-field level by solving the nonlinear Gross-Pitaevskii equation in a double well potential, and (c) at an exact many-body level by solving the time-dependent many-body Schr\\"odinger equation. We propose a control protocol to transfer atoms from the ground state of a well to the ground state of the neighbouring well. Furthermore, we show that the detrimental effects of the inter-particle repulsion can be eliminated by means of a compensating control pulse, yielding, quite surprisingly, an enhancement of the transfer speed because of the particle interaction -- in contrast to the self-trapping scenario. Finally, we perform numerical optimisations of both the nonlinear and the (exact) many-body quantum dynamics in order to further enhance the transfer efficiency close to the quantum speed limit.

  1. Creating dynamic equivalent PV circuit models with impedance spectroscopy for arc-fault modeling.

    SciTech Connect (OSTI)

    Johnson, Jay Dean; Kuszmaul, Scott S.; Strauch, Jason E.; Schoenwald, David Alan

    2011-06-01

    Article 690.11 in the 2011 National Electrical Code{reg_sign} (NEC{reg_sign}) requires new photovoltaic (PV) systems on or penetrating a building to include a listed arc fault protection device. Currently there is little experimental or empirical research into the behavior of the arcing frequencies through PV components despite the potential for modules and other PV components to filter or attenuate arcing signatures that could render the arc detector ineffective. To model AC arcing signal propagation along PV strings, the well-studied DC diode models were found to inadequately capture the behavior of high frequency arcing signals. Instead dynamic equivalent circuit models of PV modules were required to describe the impedance for alternating currents in modules. The nonlinearities present in PV cells resulting from irradiance, temperature, frequency, and bias voltage variations make modeling these systems challenging. Linearized dynamic equivalent circuits were created for multiple PV module manufacturers and module technologies. The equivalent resistances and capacitances for the modules were determined using impedance spectroscopy with no bias voltage and no irradiance. The equivalent circuit model was employed to evaluate modules having irradiance conditions that could not be measured directly with the instrumentation. Although there was a wide range of circuit component values, the complex impedance model does not predict filtering of arc fault frequencies in PV strings for any irradiance level. Experimental results with no irradiance agree with the model and show nearly no attenuation for 1 Hz to 100 kHz input frequencies.

  2. Development of an entrained flow gasifier model for process optimization study

    SciTech Connect (OSTI)

    Biagini, E.; Bardi, A.; Pannocchia, G.; Tognotti, L. [Consorzio Pisa Ric, Pisa (Italy). Div Energia Ambiente

    2009-10-15

    Coal gasification is a versatile process to convert a solid fuel in syngas, which can be further converted and separated in hydrogen, which is a valuable and environmentally acceptable energy carrier. Different technologies (fixed beds, fluidized beds, entrained flow reactors) are used, operating under different conditions of temperature, pressure, and residence time. Process studies should be performed for defining the best plant configurations and operating conditions. Although 'gasification models' can be found in the literature simulating equilibrium reactors, a more detailed approach is required for process analysis and optimization procedures. In this work, a gasifier model is developed by using AspenPlus as a tool to be implemented in a comprehensive process model for the production of hydrogen via coal gasification. It is developed as a multizonal model by interconnecting each step of gasification (preheating, devolatilization, combustion, gasification, quench) according to the reactor configuration, that is in entrained flow reactor. The model removes the hypothesis of equilibrium by introducing the kinetics of all steps and solves the heat balance by relating the gasification temperature to the operating conditions. The model allows to predict the syngas composition as well as quantity the heat recovery (for calculating the plant efficiency), 'byproducts', and residual char. Finally, in view of future works, the development of a 'gasifier model' instead of a 'gasification model' will allow different reactor configurations to be compared.

  3. Steady state and dynamic modeling of a packed bed reactor for the partial oxidation of methanol to formaldehyde: experimental results compared with model predictions

    SciTech Connect (OSTI)

    Schwedock, M.J.; Windes, L.C.; Ray, W.H.

    1985-01-01

    Heterogeneous and pseudohomogeneous models are compared to experimental data from a packed bed reactor for the partical oxidation of methanol to formaldehyde over an iron oxide-molybdenum oxide catalyst. Heat transfer parameters which were successful in matching data from experiments without reaction were not successful in matching temperature data from experiments with reaction. This made it necessary to decrease the fluid radial heat transfer to obtain good fit. A good fit was obtained for steady state composition profiles by optimizing selected frequency factors and the activation energy for methanol. A redox rate expression for the oxidation of formaldehyde to carbon monoxide was proposed since a simple first-order rate expression did not fit the data. The pseudohomogeneous model gave results similar to the heterogeneous model for both steady state and dynamic experiments and has been recommended for future experimental state estimation and control studies. 21 refs., 31 figs., 6 tabs.

  4. Probabilistic model identification of the bit-rock-interaction-model uncertainties in nonlinear dynamics of a drill-string

    E-Print Network [OSTI]

    Boyer, Edmond

    , and simple models are usually considered in the analysis. This is an important constraint when uncertaintiesProbabilistic model identification of the bit-rock-interaction-model uncertainties in nonlinear model of uncertainties in a bit-rock interaction model for the nonlinear dynamics of a drill

  5. Mixtures of Predictive Linear Gaussian Models for Nonlinear Stochastic Dynamical Systems

    E-Print Network [OSTI]

    Baveja, Satinder Singh

    Mixtures of Predictive Linear Gaussian Models for Nonlinear Stochastic Dynamical Systems David dynamical systems. The primary contribution of this work is to extend the PLG to nonlinear, stochastic- proves upon traditional linear dynamical system mod- els by using a predictive representation of state

  6. A Mathematical Tumor Model with Immune Resistance and Drug Therapy: An Optimal Control Approach

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    De Pillis, L. G.; Radunskaya, A.

    2001-01-01

    We present a competition model of cancer tumor growth that includes both the immune system response and drug therapy. This is a four-population model that includes tumor cells, host cells, immune cells, and drug interaction. We analyze the stability of the drug-free equilibria with respect to the immune response in order to look for target basins of attraction. One of our goals was to simulate qualitatively the asynchronous tumor-drug interaction known as “Jeffs phenomenon.” The model we develop is successful in generating this asynchronous response behavior. Our other goal was to identify treatment protocols that could improve standard pulsed chemotherapymore »regimens. Using optimal control theory with constraints and numerical simulations, we obtain new therapy protocols that we then compare with traditional pulsed periodic treatment. The optimal control generated therapies produce larger oscillations in the tumor population over time. However, by the end of the treatment period, total tumor size is smaller than that achieved through traditional pulsed therapy, and the normal cell population suffers nearly no oscillations.« less

  7. A Technical Review on Biomass Processing: Densification, Preprocessing, Modeling and Optimization

    SciTech Connect (OSTI)

    Jaya Shankar Tumuluru; Christopher T. Wright

    2010-06-01

    It is now a well-acclaimed fact that burning fossil fuels and deforestation are major contributors to climate change. Biomass from plants can serve as an alternative renewable and carbon-neutral raw material for the production of bioenergy. Low densities of 40–60 kg/m3 for lignocellulosic and 200–400 kg/m3 for woody biomass limits their application for energy purposes. Prior to use in energy applications these materials need to be densified. The densified biomass can have bulk densities over 10 times the raw material helping to significantly reduce technical limitations associated with storage, loading and transportation. Pelleting, briquetting, or extrusion processing are commonly used methods for densification. The aim of the present research is to develop a comprehensive review of biomass processing that includes densification, preprocessing, modeling and optimization. The specific objective include carrying out a technical review on (a) mechanisms of particle bonding during densification; (b) methods of densification including extrusion, briquetting, pelleting, and agglomeration; (c) effects of process and feedstock variables and biomass biochemical composition on the densification (d) effects of preprocessing such as grinding, preheating, steam explosion, and torrefaction on biomass quality and binding characteristics; (e) models for understanding the compression characteristics; and (f) procedures for response surface modeling and optimization.

  8. Dynamics of chains with non-monotone stress-strain relations. 1. Model and Numerical Experiments.

    E-Print Network [OSTI]

    Cherkaev, Andrej

    - tural optimization. In both cases, one deals with several materials or solid phases that are distributed 1 #12;Abstract We discuss the dynamical processes in the materials with non-monotonic constitutive-organization of a complicated mosaic structure in materials 3, 9 . The computational aspects of the solution of these problems

  9. Computational method and system for modeling, analyzing, and optimizing DNA amplification and synthesis

    DOE Patents [OSTI]

    Vandersall, Jennifer A.; Gardner, Shea N.; Clague, David S.

    2010-05-04

    A computational method and computer-based system of modeling DNA synthesis for the design and interpretation of PCR amplification, parallel DNA synthesis, and microarray chip analysis. The method and system include modules that address the bioinformatics, kinetics, and thermodynamics of DNA amplification and synthesis. Specifically, the steps of DNA selection, as well as the kinetics and thermodynamics of DNA hybridization and extensions, are addressed, which enable the optimization of the processing and the prediction of the products as a function of DNA sequence, mixing protocol, time, temperature and concentration of species.

  10. A Dynamic Solar Core model: the SSM-like solution

    E-Print Network [OSTI]

    Attila Grandpierre

    1998-08-31

    I point out that the all the arguments against an astrophysical solution do not exclude a yet not recognised class of solar models, in which an explosive energy source is present in the solar core besides the standard pp and CNO cycle. It is shown from first principle physics that stars have a non-pp,CNO source: local thermonuclear runaways. I derive a model independent inequality, which shows that the problem of the missing beryllium neutrinos lies in that the SuperKamiokande contains a term arising from neutrinos from a runaway source which can produce high-energy electrons and high-energy axions, and muon and tau neutrinos. I point out, that the temperature dependence of the individual neutrino fluxes is related to pure nuclear physics but the usual luminosity constraint is model dependent and actually is a questionable assumption. Allowing non-pp,CNO reaction chains a new approach arises to interpret the neutrino detector data. The explicit temperature dependence leads to $\\Phi_{pp} \\propto T^4$ instead of the usual $\\Phi_{pp} \\propto T^{-1/2}$ for the SSM luminosity constraint. I assume a Sun analogue to the SSM with a different $T_c$. The separate neutrino detector equations lead to separate detector-related temperatures with the neutrino detector data. The results show a slightly lower than standard central temperature. I attempt to show that helioseismology is not in a necessary conflict with the dynamic solar model presented here. The results of the calculations may propose solutions to the problems of solar and atmospheric neutrino oscillations without an ad hoc introduction of sterile neutrinos and present predictions to Borexino and SNO measurements. {\\it PACS numbers}: 26.65+t, 26.30.+k, 96.60Jw, 95.30.Cq

  11. Modeling and Optimization of PEMFC Systems and its Application to Direct Hydrogen Fuel Cell Vehicles

    E-Print Network [OSTI]

    Zhao, Hengbing; Burke, Andy

    2008-01-01

    and Optimization of PEMFC Systems and its Application toand Optimization of PEMFC Systems and its Application onExchange Membrane fuel cell (PEMFC) technology for use in

  12. Progress on Optimization of the Nonlinear Beam Dynamics in the MEIC

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech ConnectSpeeding accessusers'(x≤2)Article)SciTechon MPAS Land Ice ModelCollider

  13. Complex Dynamics in Equilibrium Asset Pricing Models with Boundedly Rational, Heterogeneous

    E-Print Network [OSTI]

    their optimal portfolio and the market equilibrium, investors must compute future aggregate demands for assets] for critiques of equilibrium models and the response [4] by Robert Lucas. 3The Lucas [5] paper is one one

  14. A Dynamic Solar Core Model: the Deviant Temperatures Approach

    E-Print Network [OSTI]

    Attila Grandpierre

    1998-08-31

    I derive here a model independent inequality which shows that the problem of the missing beryllium neutrinos of the Sun roots in the fact that the SuperKamiokande contains a term arising from a non-pp,CNO source. First principle physics shows that the non-pp,CNO source is of thermonuclear runaway origin. Several indications suggest that the non-pp,CNO term plays a more significant role in the solar neutrino problems than neutrino oscillations. When removing the over-restricted SSM luminosity constraint, the temperature dependence of the neutrino fluxes is related to pure nuclear physics and follows $\\Phi_{pp} \\propto T^4$ instead of $\\Phi_{pp} \\propto T^{-1/2}$. The results of the calculations offer solutions to the solar neutrino problems and problems of neutrino oscillations. The dynamic solar model presents predictions to Borexino and SNO measurements. These predictions can serve to distinguish between the MSW and the non-pp,CNO effect. {\\it PACS numbers|: 26.65.+t, 26.30.+k, 96.60.JW, 95.30.Cq

  15. The challenges of modelling antibody repertoire dynamics in HIV infection

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Luo, Shishi; Perelson, Alan S.

    2015-07-20

    Antibody affinity maturation by somatic hypermutation of B-cell immunoglobulin variable region genes has been studied for decades in various model systems using well-defined antigens. While much is known about the molecular details of the process, our understanding of the selective forces that generate affinity maturation are less well developed, particularly in the case of a co-evolving pathogen such as HIV. Despite this gap in understanding, high-throughput antibody sequence data are increasingly being collected to investigate the evolutionary trajectories of antibody lineages in HIV-infected individuals. Here, we review what is known in controlled experimental systems about the mechanisms underlying antibody selectionmore »and compare this to the observed temporal patterns of antibody evolution in HIV infection. In addition, we describe how our current understanding of antibody selection mechanisms leaves questions about antibody dynamics in HIV infection unanswered. Without a mechanistic understanding of antibody selection in the context of a co-evolving viral population, modelling and analysis of antibody sequences in HIV-infected individuals will be limited in their interpretation and predictive ability.« less

  16. Ultrafast Structural Dynamics in Combustion Relevant Model Systems

    SciTech Connect (OSTI)

    Weber, Peter M.

    2014-03-31

    The research project explored the time resolved structural dynamics of important model reaction system using an array of novel methods that were developed specifically for this purpose. They include time resolved electron diffraction, time resolved relativistic electron diffraction, and time resolved Rydberg fingerprint spectroscopy. Toward the end of the funding period, we also developed time-resolved x-ray diffraction, which uses ultrafast x-ray pulses at LCLS. Those experiments are just now blossoming, as the funding period expired. In the following, the time resolved Rydberg Fingerprint Spectroscopy is discussed in some detail, as it has been a very productive method. The binding energy of an electron in a Rydberg state, that is, the energy difference between the Rydberg level and the ground state of the molecular ion, has been found to be a uniquely powerful tool to characterize the molecular structure. To rationalize the structure sensitivity we invoke a picture from electron diffraction: when it passes the molecular ion core, the Rydberg electron experiences a phase shift compared to an electron in a hydrogen atom. This phase shift requires an adjustment of the binding energy of the electron, which is measurable. As in electron diffraction, the phase shift depends on the molecular, geometrical structure, so that a measurement of the electron binding energy can be interpreted as a measurement of the molecule’s structure. Building on this insight, we have developed a structurally sensitive spectroscopy: the molecule is first elevated to the Rydberg state, and the binding energy is then measured using photoelectron spectroscopy. The molecule’s structure is read out as the binding energy spectrum. Since the photoionization can be done with ultrafast laser pulses, the technique is inherently capable of a time resolution in the femtosecond regime. For the purpose of identifying the structures of molecules during chemical reactions, and for the analysis of molecular species in the hot environments of combustion processes, there are several features that make the Rydberg ionization spectroscopy uniquely useful. First, the Rydberg electron’s orbit is quite large and covers the entire molecule for most molecular structures of combustion interest. Secondly, the ionization does not change vibrational quantum numbers, so that even complicated and large molecules can be observed with fairly well resolved spectra. In fact, the spectroscopy is blind to vibrational excitation of the molecule. This has the interesting consequence for the study of chemical dynamics, where the molecules are invariably very energetic, that the molecular structures are observed unobstructed by the vibrational congestion that dominates other spectroscopies. This implies also that, as a tool to probe the time-dependent structural dynamics of chemically interesting molecules, Rydberg spectroscopy may well be better suited than electron or x-ray diffraction. With recent progress in calculating Rydberg binding energy spectra, we are approaching the point where the method can be evolved into a structure determination method. To implement the Rydberg ionization spectroscopy we use a molecular beam based, time-resolved pump-probe multi-photon ionization/photoelectron scheme in which a first laser pulse excites the molecule to a Rydberg state, and a probe pulse ionizes the molecule. A time-of-flight detector measures the kinetic energy spectrum of the photoelectrons. The photoelectron spectrum directly provides the binding energy of the electron, and thereby reveals the molecule’s time-dependent structural fingerprint. Only the duration of the laser pulses limits the time resolution. With a new laser system, we have now reached time resolutions better than 100 fs, although very deep UV wavelengths (down to 190 nm) have slightly longer instrument functions. The structural dynamics of molecules in Rydberg-excited states is obtained by delaying the probe ionization photon from the pump photon; the structural dynamics of molecules in their ground state or e

  17. Stochastic model for aerodynamic force dynamics on wind turbine blades in unsteady wind inflow

    E-Print Network [OSTI]

    Luhur, Muhammad Ramzan; Kühn, Martin; Wächter, Matthias

    2015-01-01

    The paper presents a stochastic approach to estimate the aerodynamic forces with local dynamics on wind turbine blades in unsteady wind inflow. This is done by integrating a stochastic model of lift and drag dynamics for an airfoil into the aerodynamic simulation software AeroDyn. The model is added as an alternative to the static table lookup approach in blade element momentum (BEM) wake model used by AeroDyn. The stochastic forces are obtained for a rotor blade element using full field turbulence simulated wind data input and compared with the classical BEM and dynamic stall models for identical conditions. The comparison shows that the stochastic model generates additional extended dynamic response in terms of local force fluctuations. Further, the comparison of statistics between the classical BEM, dynamic stall and stochastic models' results in terms of their increment probability density functions gives consistent results.

  18. On linking an Earth system model to the equilibrium carbon representation of an economically optimizing land use model

    SciTech Connect (OSTI)

    Bond-Lamberty, Benjamin; Calvin, Katherine V.; Jones, Andrew D.; Mao, Jiafu; Patel, Pralit L.; Shi, Xiaoying; Thomson, Allison M.; Thornton, Peter E.; Zhou, Yuyu

    2014-01-01

    Human activities are significantly altering biogeochemical cycles at the global scale, posing a significant problem for earth system models (ESMs), which may incorporate static land-use change inputs but do not actively simulate policy or economic forces. One option to address this problem is a to couple an ESM with an economically oriented integrated assessment model. Here we have implemented and tested a coupling mechanism between the carbon cycles of an ESM (CLM) and an integrated assessment (GCAM) model, examining the best proxy variables to share between the models, and quantifying our ability to distinguish climate- and land-use-driven flux changes. CLM’s net primary production and heterotrophic respiration outputs were found to be the most robust proxy variables by which to manipulate GCAM’s assumptions of long-term ecosystem steady state carbon, with short-term forest production strongly correlated with long-term biomass changes in climate-change model runs. By leveraging the fact that carbon-cycle effects of anthropogenic land-use change are short-term and spatially limited relative to widely distributed climate effects, we were able to distinguish these effects successfully in the model coupling, passing only the latter to GCAM. By allowing climate effects from a full earth system model to dynamically modulate the economic and policy decisions of an integrated assessment model, this work provides a foundation for linking these models in a robust and flexible framework capable of examining two-way interactions between human and earth system processes.

  19. Optimal modeling of 1D azimuth correlations in the context of Bayesian inference

    E-Print Network [OSTI]

    Michiel B. De Kock; Hans C. Eggers; Thomas A. Trainor

    2015-02-16

    Analysis and interpretation of spectrum and correlation data from high-energy nuclear collisions is currently controversial because two opposing physics narratives derive contradictory implications from the same data-one narrative claiming collision dynamics is dominated by dijet production and projectile-nucleon fragmentation, the other claiming collision dynamics is dominated by a dense, flowing QCD medium. Opposing interpretations seem to be supported by alternative data models, and current model-comparison schemes are unable to distinguish between them. There is clearly need for a convincing new methodology to break the deadlock. In this study we introduce Bayesian Inference (BI) methods applied to angular correlation data as a basis to evaluate competing data models. For simplicity the data considered are projections of 2D angular correlations onto 1D azimuth from three centrality classes of 200 GeV Au-Au collisions. We consider several data models typical of current model choices, including Fourier series (FS) and a Gaussian plus various combinations of individual cosine components. We evaluate model performance with BI methods and with power-spectrum (PS) analysis. We find that the FS-only model is rejected in all cases by Bayesian analysis which always prefers a Gaussian. A cylindrical quadrupole cos(2\\phi) is required in some cases but rejected for most-central Au-Au collisions. Given a Gaussian centered at the azimuth origin "higher harmonics" cos(m\\phi) for m > 2 are rejected. A model consisting of Gaussian + dipole cos(\\phi) + quadrupole cos(2\\phi) provides good 1D data descriptions in all cases.

  20. Modeling and optimizing of the random atomic spin gyroscope drift based on the atomic spin gyroscope

    SciTech Connect (OSTI)

    Quan, Wei; Lv, Lin Liu, Baiqi

    2014-11-15

    In order to improve the atom spin gyroscope's operational accuracy and compensate the random error caused by the nonlinear and weak-stability characteristic of the random atomic spin gyroscope (ASG) drift, the hybrid random drift error model based on autoregressive (AR) and genetic programming (GP) + genetic algorithm (GA) technique is established. The time series of random ASG drift is taken as the study object. The time series of random ASG drift is acquired by analyzing and preprocessing the measured data of ASG. The linear section model is established based on AR technique. After that, the nonlinear section model is built based on GP technique and GA is used to optimize the coefficients of the mathematic expression acquired by GP in order to obtain a more accurate model. The simulation result indicates that this hybrid model can effectively reflect the characteristics of the ASG's random drift. The square error of the ASG's random drift is reduced by 92.40%. Comparing with the AR technique and the GP + GA technique, the random drift is reduced by 9.34% and 5.06%, respectively. The hybrid modeling method can effectively compensate the ASG's random drift and improve the stability of the system.