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Office of Scientific and Technical Information
Gas hydrate cool storage system
DOE Patents [OSTI]
The invention presented relates to the development of a process utilizing a gas hydrate as a cool storage medium for alleviating electric load demands during peak usage periods. Several objectives of the invention are mentioned concerning the formation of the gas hydrate as storage material in a thermal energy storage system within a heat pump cycle system. The gas hydrate was formed using a refrigerant in water and an example with R-12 refrigerant is included. (BCS)
Ternes, M.P.; Kedl, R.J.
Molecular dynamics simulation of hydration in myoglobin
SciTech Connect (OSTI)
This study was carried out to evaluate the stability of the 89 bound water molecules that were observed in the neutron diffraction study of CO myoglobin. The myoglobin structure derived from the neutron analysis was used as the starting point in the molecular dynamics simulation using the software package CHARMM. After salvation of the protein, energy minimization and equilibration of the system, 50 pico seconds of Newtonian dynamics was performed. This data showed that only 4 water molecules are continously bound during the length of this simulation while the other solvent molecules exhibit considerable mobility and are breaking and reforming hydrogen bonds with the protein. At any instant during the simulation, 73 of the hydration sites observed in the neutron structure are occupied by water.
Gu, Wei [New Mexico Univ., Albuquerque, NM (United States). Dept. of Biochemistry; Schoenborn, B.P. [Los Alamos National Lab., NM (United States)
Hydration water dynamics and instigation of protein structuralrelaxation
Until a critical hydration level is reached, proteins do not function. This critical level of hydration is analogous to a similar lack of protein function observed for temperatures below a dynamical temperature range of 180-220K that also is connected to the dynamics of protein surface water. Restoration of some enzymatic activity is observed in partially hydrated protein powders, sometimes corresponding to less than a single hydration layer on the protein surface, which indicates that the dynamical and structural properties of the surface water is intimately connected to protein stability and function. Many elegant studies using both experiment and simulation have contributed important information about protein hydration structure and timescales. The molecular mechanism of the solvent motion that is required to instigate the protein structural relaxation above a critical hydration level or transition temperature has yet to be determined. In this work we use experimental quasi-elastic neutron scattering (QENS) and molecular dynamics simulation to investigate hydration water dynamics near a greatly simplified protein system. We consider the hydration water dynamics near the completely deuterated N-acetyl-leucine-methylamide (NALMA) solute, a hydrophobic amino acid side chain attached to a polar blocked polypeptide backbone, as a function of concentration between 0.5M-2.0M under ambient conditions. We note that roughly 50-60% of a folded protein's surface is equally distributed between hydrophobic and hydrophilic domains, domains whose lengths are on the order of a few water diameters, that justify our study of hydration dynamics of this simple model protein system. The QENS experiment was performed at the NIST Center for Neutron Research, using the disk chopper time of flight spectrometer (DCS). In order to separate the translational and rotational components in the spectra, two sets of experiments were carried out using different incident neutron wavelengths of 7.5{angstrom} and 5.5{angstrom} to give two different time resolutions. All the spectra have been measure at room temperature. The spectra were corrected for the sample holder contribution and normalized using the vanadium standard. The resulting data were analyzed with DAVE programs (http://www.ncnr.nist.gov/dave/). The AMBER force field and SPCE water model were used for modeling the NALMA solute and water, respectively. For the analysis of the water dynamics in the NALMA aqueous solutions, we performed simulations of a dispersed solute configuration consistent with our previous structural analysis, where we had primarily focused on the structural organization of these peptide solutions and their connection to protein folding. Further details of the QENS experiment and molecular dynamics simulations are reported elsewhere.
Russo, Daniela; Hura, Greg; Head-Gordon, Teresa
Hydration-dependent dynamics of deeply cooled water under strong confinement
E-Print Network [OSTI]
We have measured the hydration-level dependence of the single-particle dynamics of water confined in the ordered mesoporous silica MCM-41. The dynamic crossover observed at full hydration is absent at monolayer hydration. ...
Bertrand, C. E.
Dynamical Transition and Heterogeneous Hydration Dynamics in RNA
Enhanced dynamical fluctuations of RNAs, facilitated by a network of water molecules with strong interactions with RNA, are suspected to be critical in their ability to respond to a variety of cellular signals. Using atomically detailed molecular dynamics simulations at various temperatures of purine (adenine)- and preQ$_1$ sensing riboswitch aptamers, we show that water molecules in the vicinity of RNAs undergo complex dynamics depending on the local structures of the RNAs. The overall lifetimes of hydrogen bonds (HBs) of surface bound waters are more than at least 1-2 orders of magnitude longer than bulk water. Slow hydration dynamics, revealed in non-Arrhenius behavior of the relaxation time, arises from high activation barriers to break water hydrogen bonds with a nucleotide and by reduced diffusion of water. The relaxation kinetics at specific locations in the two RNAs show a broad spectrum of time scales reminiscent of glass-like behavior, suggesting that the hydration dynamics is highly heterogeneous. Both RNAs undergo dynamic transition at $T = T_D \\gtrsim 200$ K as assessed by the mean square fluctuation of hydrogen atoms $\\langle x^2\\rangle$, which undergoes an abrupt harmonic-to-anharmonic transition at $T_D$. The near universal value of $T_D$ found for these RNAs and previously for tRNA is strongly correlated with changes in hydration dynamics as $T$ is altered. Hierarchical dynamics of waters associated with the RNA surface, revealed in the motions of distinct classes of water with well-separated time scales, reflects the heterogeneous local environment on the molecular surface of RNA. At low temperatures slow water dynamics predominates over structural transitions. Our study demonstrates that the complex interplay of dynamics between water and local environment in the RNA structures could be a key determinant of the functional activities of RNA.
Jeseong Yoon; Jong-Chin Lin; Changbong Hyeon; D. Thirumalai
Hydration dynamics near a model protein surface
AE, Onuchic JN. 2002. Protein folding mediated by solvation:of hydration forces in protein folding. Journal of Physicalthe broader context of protein folding and function and as
This invention is a process for formation of a gas hydrate to be used as a cool storage medium using a refrigerant in water. Mixing of the immiscible refrigerant and water is effected by addition of a surfactant and agitation. The difficult problem of subcooling during the process is overcome by using the surfactant and agitation and performance of the process significantly improves and approaches ideal.
Ternes, Mark P. (Knoxville, TN); Kedl, Robert J. (Oak Ridge, TN)
Effects of hydration water on protein methyl group dynamics insolution
Elastic and quasielastic neutron scattering experiments have been used to investigate the dynamics of methyl groups in a protein-model hydrophobic peptide in solution. The results suggest that, when the hydrophobic side chains are hydrated by a single hydration water layer, the only allowed motions are confined and attributed to librational and rotational movement associated with the methyl groups. They provide unique experimental evidence that the structural and dynamical properties of the interfacial water strongly influence the side-chain dynamics and the activation of diffusive motion.
Russo D; Hura GL; Copley JRD
Dynamics of lysozyme and its hydration water under electric field
The effects of static electric field on the dynamics of lysozyme and its hydration water have been investigated by means of incoherent quasi-elastic neutron scattering (QENS). Measurements were performed on lysozyme samples, hydrated respectively with heavy water (D2O) to capture the protein dynamics, and with light water (H2O), to probe the dynamics of the hydration shell, in the temperature range from 210 < T < 260 K. The hydration fraction in both cases was about 0.38 gram of water per gram of dry protein. The field strengths investigated were respectively 0 kV/mm and 2 kV/mm ( 2 106 V/m) for the protein hydrated with D2O and 0 kV and 1 kV/mm for the H2O-hydrated counterpart. While the overall internal protons dynamics of the protein appears to be unaffected by the application of electric field up to 2 kV/mm, likely due to the stronger intra-molecular interactions, there is also no appreciable quantitative enhancement of the diffusive dynamics of the hydration water, as would be anticipated based on our recent observations in water confined in silica pores under field values of 2.5 kV/mm. This may be due to the difference in surface interactions between water and the two adsorption hosts (silica and protein), or to the existence of a critical threshold field value Ec 2 3 kV/mm for increased molecular diffusion, for which electrical breakdown is a limitation for our sample.
Favi, Pelagie M [ORNL; Zhang, Qiu [ORNL; O'Neill, Hugh Michael [ORNL; Mamontov, Eugene [ORNL; Omar Diallo, Souleymane [ORNL; Palmer, Jeremy [North Carolina State University
Dynamics of biopolymers and their hydration water studied by neutron and X-ray scattering
Protein functions are intimately related to their dynamics. Moreover, protein hydration water is believed to have significant influence on the dynamics of proteins. One of the evidence is that both protein and its hydration ...
Chu, Xiang-qiang
Method for controlling clathrate hydrates in fluid systems
Discussed is a process for preventing clathrate hydrate masses from impeding the flow of fluid in a fluid system. An additive is contacted with clathrate hydrate masses in the system to prevent those clathrate hydrate masses from impeding fluid flow. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member and/or six member cyclic chemical groupings. Additives include poly(N-vinyl-2-pyrrolidone) and hydroxyethylcellulose, either in combination or alone.
Sloan, Jr., Earle D. (Golden, CO)
Hydration structure of salt solutions from ab initio molecular dynamics
The solvation structures of Na{sup +}, K{sup +}, and Cl{sup -} ions in aqueous solution have been investigated using density functional theory (DFT) based Car-Parrinello (CP) molecular dynamics (MD) simulations. CPMD trajectories were collected for systems containing three NaCl or KCl ion pairs solvated by 122 water molecules using three different but commonly employed density functionals (BLYP, HCTH, and PBE) with electron correlation treated at the level of the generalized gradient approximation (GGA). The effect of including dispersion forces was analyzed through the use of an empirical correction to the DFT-GGA scheme. Special attention was paid to the hydration characteristics, especially the structural properties of the first solvation shell of the ions, which was investigated through ion-water radial distribution functions, coordination numbers, and angular distribution functions. There are significant differences between the present results obtained from CPMD simulations and those provided by classical MD based on either the CHARMM force field or a polarizable model. Overall, the computed structural properties are in fair agreement with the available experimental results. In particular, the observed coordination numbers 5.0-5.5, 6.0-6.4, and 6.0-6.5 for Na{sup +}, K{sup +}, and Cl{sup -}, respectively, are consistent with X-ray and neutron scattering studies but differ somewhat from some of the many other recent computational studies of these important systems. Possible reasons for the differences are discussed.
Bankura, Arindam; Carnevale, Vincenzo; Klein, Michael L. [Institute for Computational Molecular Science and Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122 (United States)
Simulation studies of slow dynamics of hydration water in lysozyme : hydration level dependence and comparison with experiment using new time domain analysis
A series of Molecular Dynamics (MD) simulations using the GROMACS� package has been performed in this thesis. It is used to mimic and simulate the hydration water in Lysozyme with three different hydration levels (h = 0.3, ...
Kim, Chansoo, S.M. Massachusetts Institute of Technology
Dynamics of Confined Water Molecules in Aqueous Salt Hydrates
The unusual properties of water are largely dictated by the dynamics of the H bond network. A single water molecule has more H bonding sites than atoms, hence new experimental and theoretical investigations about this peculiar liquid have not ceased to appear. Confinement of water to nanodroplets or small molecular clusters drastically changes many of the liquid�s properties. Such confined water plays a major role in the solvation of macro molecules such as proteins and can even be essential to their properties. Despite the vast results available on bulk and confined water, discussions about the correlation between spectral and structural properties continue to this day. The fast relaxation of the OH stretching vibration in bulk water, and the variance of sample geometries in the experiments on confined water obfuscate definite interpretation of the spectroscopic results in terms of structural parameters. We present first time-resolved investigations on a new model system that is ideally suited to overcome many of the problems faced in spectroscopical investigation of the H bond network of water. Aqueous hydrates of inorganic salts provide water molecules in a crystal grid, that enables unambiguous correlations of spectroscopic and structural features. Furthermore, the confined water clusters are well isolated from each other in the crystal matrix, so different degrees of confinement can be achieved by selection of the appropriate salt.
Werhahn, Jasper C.; Pandelov, S.; Yoo, Soohaeng; Xantheas, Sotiris S.; Iglev, H.
Rock-physics Models for Gas-hydrate Systems Associated
Rock-physics Models for Gas-hydrate Systems Associated with Unconsolidated Marine Sediments Diana associated with unconsolidated marine sediments. The goals are to predict gas-hydrate concentration from intercalated with unconsolidated sediments. We show that the geometrical details of how gas hy- drates
Texas at Austin, University of
Discussed is a process for preventing clathrate hydrate masses from impeding the flow of fluid in a fluid system. An additive is contacted with clathrate hydrate masses in the system to prevent those clathrate hydrate masses from impeding fluid flow. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member, six member and/or seven member cyclic chemical groupings. Additives include poly(N-vinyl-2-pyrrolidone) and hydroxyethylcellulose, either in combination or alone. Additives can also contain multiple cyclic chemical groupings having different size rings. One such additive is sold under the name Gaffix VC-713.
Sloan, E.D. Jr.
Dynamical properties of the hydration shell of fully deuterated myoglobin
Freeze-dried perdeuterated sperm whale myoglobin was kept in a water-saturated atmosphere in order to obtain a hydration degree of 335 {sup 1}H{sub 2}O molecules per one myoglobin molecule. Incoherent neutron scattering was performed at the neutron spectrometer TOFTOF at the FRM II in an angular range of q from 0.6 to 1.8 A{sup -1} and a temperature range from 4 to 297 K. We used neutrons with a wavelength of {lambda}{alpha}E 6 A and an energy resolution of about 65 {mu}eV corresponding to motions faster than 10 ps. At temperatures above 225 K, broad lines appear in the spectra caused by quasielastic scattering. For an explanation of these lines, we assumed that there are only two types of protons, those that are part of the hydration water (72%) and those that belong to the protein (28%). The protons of the hydration water were analyzed with the diffusion model of Singwi and Sjoelander [Phys. Rev. 119, 863 (1960)]. In this model, a water molecule stays for a time {tau}{sub 0} in a bound state performing oscillatory motions. Thereafter, the molecule performs free diffusion for the time {tau}{sub 1} in a nonbound state followed again by the oscillatory motions for {tau}{sub 0} and so forth. We used the general formulation with no simplifications as {tau}{sub 0}>>{tau}{sub 1} or {tau}{sub 1}>>{tau}{sub 0}. At room temperature, we obtained {tau}{sub 0} {alpha}E 104 ps and {tau}{sub 1} {alpha}E 37 ps. For the protein bound hydrogen, the dynamics is described by a Brownian oscillator where the protons perform overdamped motions in limited space.
Achterhold, Klaus; Parak, Fritz G. [Physik-Department E17, Technische Universitaet Muenchen, James-Franck-Strasse 1, D-85747 Garching (Germany); Ostermann, Andreas [Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II), ZWE, Lichtenbergstrasse 1, D-85747 Garching (Germany); Moulin, Martine; Haertlein, Michael [ILL-EMBL Deuteration Laboratory, Partnership for Structural Biology, 6, rue Jules Horowitz, F-38042 Grenoble Cedex 9 (France); Unruh, Tobias [Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II), ZWE, Lichtenbergstrasse 1, D-85747 Garching (Germany); Institut fuer Physik der Kondensierten Materie, Lehrstuhl fuer Kristallographie und Strukturphysik, Staudtstrasse 3, D-91058 Erlangen (Germany)
Dynamics of a globular protein and its hydration water studied by neutron scattering and MD simulations
This review article describes our neutron scattering experiments made in the past four years for the understanding of the single-particle (hydrogen atom) dynamics of a protein and its hydration water and the strong coupling ...
Chen, Sow-Hsin
Natural Gas Hydrate Particles in Oil-Free Systems with Kinetic Inhibition and Slurry Viscosity Reduction
Natural Gas Hydrate Particles in Oil-Free Systems with Kinetic Inhibition and Slurry Viscosity, reduction of slurry viscosity, and corrosion inhibition. INTRODUCTION Water often forms gas hydrates antiagglomeration (AA) in the natural gas hydrate literature. The main limitation to application has been the need
Firoozabadi, Abbas
Coupling of the hydration water dynamics and the internal dynamics of actin detected by quasielastic neutron scattering
Highlights: ? Quasielastic neutron scattering spectra of F-actin and G-actin were measured. ? Analysis of the samples in D{sub 2}O and H{sub 2}O provided the spectra of hydration water. ? The first layer hydration water around F-actin is less mobile than around G-actin. ? This difference in hydration water is in concert with the internal dynamics of actin. ? Water outside the first layer behaves bulk-like but influenced by the first layer. -- Abstract: In order to characterize dynamics of water molecules around F-actin and G-actin, quasielastic neutron scattering experiments were performed on powder samples of F-actin and G-actin, hydrated either with D{sub 2}O or H{sub 2}O, at hydration ratios of 0.4 and 1.0. By combined analysis of the quasielastic neutron scattering spectra, the parameter values characterizing the dynamics of the water molecules in the first hydration layer and those of the water molecules outside of the first layer were obtained. The translational diffusion coefficients (D{sub T}) of the hydration water in the first layer were found to be 1.2 � 10{sup ?5} cm{sup 2}/s and 1.7 � 10{sup ?5} cm{sup 2}/s for F-actin and G-actin, respectively, while that for bulk water was 2.8 � 10{sup ?5} cm{sup 2}/s. The residence times were 6.6 ps and 5.0 ps for F-actin and G-actin, respectively, while that for bulk water was 0.62 ps. These differences between F-actin and G-actin, indicating that the hydration water around G-actin is more mobile than that around F-actin, are in concert with the results of the internal dynamics of F-actin and G-actin, showing that G-actin fluctuates more rapidly than F-actin. This implies that the dynamics of the hydration water is coupled to the internal dynamics of the actin molecules. The D{sub T} values of the water molecules outside of the first hydration layer were found to be similar to that of bulk water though the residence times are strongly affected by the first hydration layer. This supports the recent observation on intracellular water that shows bulk-like behavior.
Fujiwara, Satoru, E-mail: email@example.com [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan)] [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Plazanet, Marie [Laboratoire Interdisciplinaire de Physique, Universit� Joseph Fourier de Grenoble and CNRS (UMR5588), BP87, 38402 Saint Martin d'H�res Cedex 9 (France)] [Laboratoire Interdisciplinaire de Physique, Universit� Joseph Fourier de Grenoble and CNRS (UMR5588), BP87, 38402 Saint Martin d'H�res Cedex 9 (France); Oda, Toshiro [RIKEN SPring-8 Center, RIKEN Harima Institute, Sayo, Hyogo 679-5148 (Japan)] [RIKEN SPring-8 Center, RIKEN Harima Institute, Sayo, Hyogo 679-5148 (Japan)
Dynamic control of slow water transport by aquaporin 0: Implications for hydration
Dynamic control of slow water transport by aquaporin 0: Implications for hydration and junction as the primary water channel in this tissue but also appears to mediate the formation of thin junctions between fiber cells. AQP0 is remarkably less water perme- able than other aquaporins, but the structural basis
Shaw, David E.
Methane escape from gas hydrate systems in marine environment, and methane-driven oceanic eruptions
Methane escape from gas hydrate systems in marine environment, and methane-driven oceanic eruptions quantities of CH4 are stored in marine sediment in the form of methane hydrate, bubbles, and dissolved CH4 in pore water. Here I discuss the various pathways for methane to enter the ocean and atmosphere
Zhang, Youxue
TOUGH+Hydrate v1.0 User's Manual: A Code for the Simulation of System Behavior in Hydrate-Bearing Geologic Media
TOUGH+HYDRATE v1.0 is a new code for the simulation of the behavior of hydrate-bearing geologic systems. By solving the coupled equations of mass and heat balance, TOUGH+HYDRATE can model the non-isothermal gas release, phase behavior and flow of fluids and heat under conditions typical of common natural CH{sub 4}-hydrate deposits (i.e., in the permafrost and in deep ocean sediments) in complex geological media at any scale (from laboratory to reservoir) at which Darcy's law is valid. TOUGH+HYDRATE v1.0 includes both an equilibrium and a kinetic model of hydrate formation and dissociation. The model accounts for heat and up to four mass components, i.e., water, CH{sub 4}, hydrate, and water-soluble inhibitors such as salts or alcohols. These are partitioned among four possible phases (gas phase, liquid phase, ice phase and hydrate phase). Hydrate dissociation or formation, phase changes and the corresponding thermal effects are fully described, as are the effects of inhibitors. The model can describe all possible hydrate dissociation mechanisms, i.e., depressurization, thermal stimulation, salting-out effects and inhibitor-induced effects. TOUGH+HYDRATE is the first member of TOUGH+, the successor to the TOUGH2 [Pruess et al., 1991] family of codes for multi-component, multiphase fluid and heat flow developed at the Lawrence Berkeley National Laboratory. It is written in standard FORTRAN 95, and can be run on any computational platform (workstation, PC, Macintosh) for which such compilers are available.
Moridis, George; Moridis, George J.; Kowalsky, Michael B.; Pruess, Karsten
The dynamic response of oceanic hydrate deposits to ocean temperature change
Moridis, G.J. (2007), Oceanic gas hydrate instability andand salt inhibition of gas hydrate formation in the northernI.R. (1999), Thermogenic gas hydrates and hydrocarbon gases
Reagan, Matthew T.
Product design and development of an aerodynamic hydration system for bicycling and triathlon
Proper hydration and aerodynamic performance are both essential needs of a competitive cyclist or triathlete. Several aerodynamic systems have been developed for use on bicycles but few have been designed to be truly ...
Cote, Mark (Mark Brian)
Office of Scientific and Technical Information (OSTI)
SYSTEM THORIUM NITRATE-WATER-NITRIC ACID AT 25 AND THE HYDRATES OF THORIUM NITRATE Re-direct Destination: Temp Data Fields Ferraro, J.R.; Katzin, L.I. Temp Data Storage 3: Argonne...
SYSTEM THORIUM NITRATE-WATER-NITRIC ACID AT 25 AND THE HYDRATES OF THORIUM NITRATE Re-direct Destination: times redirected to final destination ShortURL Code Published Current...
Modeling of structure H hydrate equilibria for methane, intermediate hydrocarbon molecules and water systems
Clathrate hydrates are inclusion compounds in which guest molecules are engaged by water molecules under favorable conditions of pressure and temperature. The well known structures 1 and 2 have been discovered since last century, while a new structure called H has been recently described in the literature. Since that time, structure H hydrate equilibrium data involving methane and different intermediate liquid hydrocarbon molecules have been published. The equilibrium calculations involving hydrates are based on the fact that the chemical potential of water in the aqueous liquid phase is equal to the one in the hydrate phase. The chemical potential of water in the liquid aqueous phase can be easily described by classical thermodynamic relations, while the chemical potential of water in the hydrates phase is described by the expressions proposed by Van der Walls and Platteeuw derived from an adsorption model based on statistical thermodynamics. The authors present in this paper a set of Kihara potential parameters which enable the calculation of Langmuir constants which characterize the adsorption of some naphthenic and iso-paraffinic intermediate hydrocarbons in the larger cage of structure H hydrates. This work thus allows the computation of structural H hydrate equilibrium conditions for systems made of methane, intermediate hydrocarbon molecules and water.
Thomas, M.; Behar, E. [Inst. Francais du Petrole, Rueil-Malmaison (France)
Desalination utilizing clathrate hydrates (LDRD final report).
Advances are reported in several aspects of clathrate hydrate desalination fundamentals necessary to develop an economical means to produce municipal quantities of potable water from seawater or brackish feedstock. These aspects include the following, (1) advances in defining the most promising systems design based on new types of hydrate guest molecules, (2) selection of optimal multi-phase reactors and separation arrangements, and, (3) applicability of an inert heat exchange fluid to moderate hydrate growth, control the morphology of the solid hydrate material formed, and facilitate separation of hydrate solids from concentrated brine. The rate of R141b hydrate formation was determined and found to depend only on the degree of supercooling. The rate of R141b hydrate formation in the presence of a heat exchange fluid depended on the degree of supercooling according to the same rate equation as pure R141b with secondary dependence on salinity. Experiments demonstrated that a perfluorocarbon heat exchange fluid assisted separation of R141b hydrates from brine. Preliminary experiments using the guest species, difluoromethane, showed that hydrate formation rates were substantial at temperatures up to at least 12 C and demonstrated partial separation of water from brine. We present a detailed molecular picture of the structure and dynamics of R141b guest molecules within water cages, obtained from ab initio calculations, molecular dynamics simulations, and Raman spectroscopy. Density functional theory calculations were used to provide an energetic and molecular orbital description of R141b stability in both large and small cages in a structure II hydrate. Additionally, the hydrate of an isomer, 1,2-dichloro-1-fluoroethane, does not form at ambient conditions because of extensive overlap of electron density between guest and host. Classical molecular dynamics simulations and laboratory trials support the results for the isomer hydrate. Molecular dynamics simulations show that R141b hydrate is stable at temperatures up to 265K, while the isomer hydrate is only stable up to 150K. Despite hydrogen bonding between guest and host, R141b molecules rotated freely within the water cage. The Raman spectrum of R141b in both the pure and hydrate phases was also compared with vibrational analysis from both computational methods. In particular, the frequency of the C-Cl stretch mode (585 cm{sup -1}) undergoes a shift to higher frequency in the hydrate phase. Raman spectra also indicate that this peak undergoes splitting and intensity variation as the temperature is decreased from 4 C to -4 C.
Simmons, Blake Alexander; Bradshaw, Robert W.; Dedrick, Daniel E.; Cygan, Randall Timothy (Sandia National Laboratories, Albuquerque, NM); Greathouse, Jeffery A. (Sandia National Laboratories, Albuquerque, NM); Majzoub, Eric H. (University of Missouri, Columbia, MO)
Additives and method for controlling clathrate hydrates in fluid systems
Discussed is a process for preventing clathrate hydrate masses from detrimentally impeding the possible flow of a fluid susceptible to clathrate hydrate formation. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member, six member and/or seven member cyclic chemical groupings. Additives include polymers having lactam rings. Additives can also contain polyelectrolytes that are believed to improve conformance of polymer additives through steric hindrance and/or charge repulsion. Also, polymers having an amide on which a C{sub 1}-C{sub 4} group is attached to the nitrogen and/or the carbonyl carbon of the amide may be used alone, or in combination with ring-containing polymers for enhanced effectiveness. Polymers having at least some repeating units representative of polymerizing at least one of an oxazoline, an N-substituted acrylamide and an N-vinyl alkyl amide are preferred.
Sloan, E.D. Jr.; Christiansen, R.L.; Lederhos, J.P.; Long, J.P.; Panchalingam, V.; Du, Y.; Sum, A.K.W.
Discussed is a process for preventing clathrate hydrate masses from detrimentally impeding the possible flow of a fluid susceptible to clathrate hydrate formation. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member, six member and/or seven member cyclic chemical groupings. Additives include polymers having lactam rings. Additives can also contain polyelectrolytes that are believed to improve conformance of polymer additives through steric hinderance and/or charge repulsion. Also, polymers having an amide on which a C.sub.1 -C.sub.4 group is attached to the nitrogen and/or the carbonyl carbon of the amide may be used alone, or in combination with ring-containing polymers for enhanced effectiveness. Polymers having at least some repeating units representative of polymerizing at least one of an oxazoline, an N-substituted acrylamide and an N-vinyl alkyl amide are preferred.
Sloan, Jr., Earle Dendy (Golden, CO); Christiansen, Richard Lee (Littleton, CO); Lederhos, Joseph P. (Wheatridge, CO); Long, Jin Ping (Dallas, TX); Panchalingam, Vaithilingam (Lakewood, CO); Du, Yahe (Golden, CO); Sum, Amadeu Kun Wan (Golden, CO)
High pressure dynamics of hydrated protein in bio-protective trehalose environment
We present a pressure dependence study of the dynamics of lysozyme protein powder immersed in deuterated $\\alpha$,$\\alpha$-trehalose environment via quasi-elastic neutron scattering (QENS). The goal is to assess the baro-protective benefits of trehalose on bio-molecules by comparing the findings with those of a trehalose-free reference study. While the mean-square displacement of the trehalose-free protein (hydrated to $d_{D_2O}\\simeq$40 w\\%) as a whole, is reduced by increasing pressure, the actual observable relaxation dynamics in the pico-(ps) to nano-seconds (ns) time range remains largely unaffected by pressure - up to the maximum investigated pressure of 2.78(2) Kbar. Our observation is independent of whether or not the protein is mixed with the deuterated sugar. This suggests that the hydrated protein's conformational states at atmospheric pressure remain unaltered by hydrostatic pressures, below 2.78 Kbar. We also found the QENS response to be totally recoverable after ambient pressure conditions are restored. Circular dichroism and neutron diffraction measurements confirm that the protein structural integrity is conserved and remains intact, after pressure is released. We observe however a clear narrowing of the quasi-elastic neutron (QENS) response as the temperature is decreased from 290 K to 230 K in both cases, which we parametrize using the Kohlrausch-Williams-Watts (KWW) stretched exponential model. Only the fraction of protons that are immobile on the accessible time window of the instrument, referred to as the elastic incoherent structure factor or (EISF) is observably sensitive to pressure, increasing only marginally but systematically with increasing pressure.
S. O. Diallo; Q. Zhang; H. O'Neill; E. Mamontov
The Effect of Simulated Barium Carbonate Waste Stream on the Hydration of Composite Cement Systems
The Effect of Simulated Barium Carbonate Waste Stream on the Hydration of Composite Cement Systems cements, comprised of ordinary Portland cement (OPC) and blast furnace slag (BFS), are used to encapsulate it is not uncommon for up to 90% of the OPC to be replaced by BFS, which will have significant effects
Sheffield, University of
The goal of this work is to quantify the Van der Waals interactions in systems involving gas hydrates. Gas hydrates are crystalline com-
gas hydrates. Gas hydrates are crystalline com- pounds that are often encountered in oil and gas briefly present the hydrate crystalline structure and the role of hydrates in oil-and gas industry the industrial contexts where they appear, we shall cite : hydrate plugs obstructing oil- or gas
Boyer, Edmond
Ab initio investigation of the first hydration shell of protonated glycine
The first hydration shell of the protonated glycine is built up using Monte Carlo multiple minimum conformational search analysis with the MMFFs force field. The potential energy surfaces of the protonated glycine and its hydration complexes with up to eight water molecules have been scanned and the energy-minimized structures are predicted using the ab initio calculations. First, three favorable structures of protonated glycine were determined, and the micro-hydration processes showed that water can significantly stabilize the unstable conformers, and then their first hydration shells were established. Finally, we found that seven water molecules are required to fully hydrate the first hydration shell for the most stable conformer of protonated glycine. In order to analyse the hydration process, the dominant hydration sites located around the ammonium and carboxyl groups are studied carefully and systemically. The results indicate that, water molecules hydrate the protonated glycine in an alternative dynamic hydration process which is driven by the competition between different hydration sites. The first three water molecules are strongly attached by the ammonium group, while only the fourth water molecule is attached by the carboxyl group in the ultimate first hydration shell of the protonated glycine. In addition, the first hydration shell model has predicted most identical structures and a reasonable accord in hydration energy and vibrational frequencies of the most stable conformer with the conductor-like polarizable continuum model.
Wei, Zhichao; Chen, Dong, E-mail: email@example.com, E-mail: email@example.com; Zhao, Huiling; Li, Yinli; Zhu, Jichun; Liu, Bo, E-mail: firstname.lastname@example.com, E-mail: firstname.lastname@example.com [Institute of Photo-Biophysics, Physics and Electronics Department, Henan University, 475004 Kaifeng (China)] [Institute of Photo-Biophysics, Physics and Electronics Department, Henan University, 475004 Kaifeng (China)
coexistence of aqueous, gas and hydrate phases in a cell (a deposit in which water, gas and hydrate are initially atequilibrium. The initial gas and hydrate saturations are S G
Moridis, George
Fluid dynamics of sinking carbon dioxide hydrate particle releases for direct ocean carbon sequestration
One strategy to remove anthropogenic CO? from the atmosphere to mitigate climate change is by direct ocean injection. Liquid CO? can react with seawater to form solid partially reacted CO? hydrate composite particles (pure ...
Chow, Aaron C. (Aaron Chunghin), 1978-
Categorical Introduction to Dynamical Systems Symbolic Dynamical Systems
Categorical Introduction to Dynamical Systems Symbolic Dynamical Systems Symbolic Embedding Examples Results Embeddings in Symbolic Dynamical Systems Jonathan Jaquette Swarthmore College July 22, 2009 Jonathan Jaquette Embeddings in Symbolic Dynamical Systems #12;Categorical Introduction
Kahng, Byung-Jay
Application of the Cell Potential Method To Predict Phase Equilibria of Multicomponent Gas Hydrate Systems
Application of the Cell Potential Method To Predict Phase Equilibria of Multicomponent Gas Hydrate the first documentation nearly two centuries ago,2 natural gas clathrate-hydrates, called clathrates, have at understanding and avoiding clathrate formation. More recently, natural gas hydrates have been proposed
Bazant, Martin Z.
Effect of bound state of water on hydronium ion mobility in hydrated Nafion using molecular dynamics simulations
We have performed a detailed analysis of the structural properties of the sulfonate groups in terms of isolated and overlapped solvation shells in the nanostructure of hydrated Nafion membrane using classical molecular dynamics simulations. Our simulations have demonstrated the correlation between the two different areas in bound water region, i.e., the first solvation shell, and the vehicular transport of hydronium ions at different water contents. We have employed a model of the Nafion membrane using the improved force field, which is newly modified and validated by comparing the density and water diffusivity with those obtained experimentally. The first solvation shells were classified into the two types, the isolated area and the overlapped area. The mean residence times of solvent molecules explicitly showed the different behaviors in each of those areas in terms of the vehicular transport of protons: the diffusivity of classical hydronium ions in the overlapped area dominates their total diffusion at lower water contents while that in the isolated area dominates for their diffusion at higher water contents. The results provided insights into the importance role of those areas in the solvation shells for the diffusivity of vehicular transport of hydronium ions in hydrated Nafion membrane.
Mabuchi, Takuya, E-mail: email@example.com [Graduate School of Engineering, Tohoku University, Sendai, Miyagi 980-8577 (Japan); Tokumasu, Takashi [Institute of Fluid Science, Tohoku University, Sendai, Miyagi 980-8577 (Japan)
Challenges, uncertainties and issues facing gas production from gas hydrate deposits
of Gas Price ($/Mscf) for Offshore Gas Hydrate StudyEvaluation of deepwater gas-hydrate systems. The Leadingfor Gas Production from Gas Hydrates Reservoirs. J. Canadian
Moridis, G.J.
in a dynamic loop and an Ostwald-de Waele model was obtained. Keywords: CO2, TBPB, mixed hydrates, solubility
Paris-Sud XI, Université de
Density Functional Calculations of ATP Systems. 1. Crystalline ATP Hydrates and Related J. Akola and R. O. Jones*
Density Functional Calculations of ATP Systems. 1. Crystalline ATP Hydrates and Related Molecules J¨lich, Germany ReceiVed: August 31, 2005; In Final Form: February 8, 2006 Adenosine 5-triphosphate (ATP ) 1, 4-7), the crystalline pyrophosphates Mg2P2O7,6H2O and R-CaNa2P2O7,4H2O, and crystalline Na2ATP,3H
Basin scale assessment of gas hydrate dissociation in response to climate change
Moridis GJ. Oceanic gas hydrate instability and dissociationKA. Potential effects of gas hydrate on human welfare, Proc.WS. A review of methane and gas hydrates in the dynamic,
Reagan, M.
Modeling of Oceanic Gas Hydrate Instability and Methane Release in Response to Climate Change
Potential effects of gas hydrate on human welfare. Proc.W.S. A review of methane and gas hydrates in the dynamic,Geology of Natural Gas Hydrates, M. Max, A.H. Johnson, W.P.
In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution
The primary accomplishment of the JOI Cooperative Agreement with DOE/NETL in this quarter was the deployment of tools and measurement systems on ODP Leg 204 to study hydrate deposits on Hydrate Ridge, offshore Oregon from July through September, 2002. During Leg 204, we cored and logged 9 sites on the Oregon continental margin to determine the distribution and concentration of gas hydrates in an accretionary ridge and adjacent slope basin, investigate the mechanisms that transport methane and other gases into the gas hydrate stability zone (GHSZ), and obtain constraints on physical properties of hydrates in situ. A 3D seismic survey conducted in 2000 provided images of potential subsurface fluid conduits and indicated the position of the GHSZ throughout the survey region. After coring the first site, we acquired Logging-While-Drilling (LWD) data at all but one site to provide an overview of downhole physical properties. The LWD data confirmed the general position of key seismic stratigraphic horizons and yielded an initial estimate of hydrate concentration through the proxy of in situ electrical resistivity. These records proved to be of great value in planning subsequent coring. The second new hydrate proxy to be tested was infrared thermal imaging of cores on the catwalk as rapidly as possible after retrieval. The thermal images were used to identify hydrate samples and to map estimate the distribution and texture of hydrate within the cores. Geochemical analyses of interstitial waters and of headspace and void gases provide additional information on the distribution and concentration of hydrate within the stability zone, the origin and pathway of fluids into and through the GHSZ, and the rates at which the process of gas hydrate formation is occurring. Bio- and lithostratigraphic description of cores, measurement of physical properties, and in situ pressure core sampling and thermal measurements complement the data set, providing ground-truth tests of inferred physical and sedimentological properties. Among the most interesting preliminary results are: (1) the discovery that gas hydrates are distributed through a broad depth range within the GHSZ and that different physical and chemical proxies for hydrate distribution and concentration give generally consistent results; (2) evidence for the importance of sediment properties for controlling the migration of fluids in the accretionary complex; (3) geochemical indications that the gas hydrate system at Hydrate Ridge contains significant concentrations of higher order hydrocarbons and that fractionation and mixing signals will provide important constraints on gas hydrate dynamics; and (4) the discovery of very high chlorinity values that extend for at least 10 mbsf near the summit, indicating that hydrate formation here must be very rapid.
Frank Rack; Gerhard Bohrmann; Anne Trehu; Michael Storms; Derryl Schroeder; ODP Leg 204 Shipboard Scientific Party
Extremes in Chaotic Dynamical Systems
Extremes in Chaotic Dynamical Systems Valerio Lucarini firstname.lastname@example.com D. Faranda Vortragsthema Datum #12;1. Introduction 2. Classical Theory: Extreme Values for i.i.d. Variables 3. Extreme Values in Dynamical Systems: Theoretical Background 4. Numerical Algorithms for studying Extremes 5
DPF -"Hydrated EGR" Fuel Saver System | Department of Energy
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
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 on Delicious Rank EERE:YearRound-UpHeat Pump Models | Department1 Prepared by: U.S.-"Hydrated EGR" Fuel Saver
Connecting curves for dynamical systems
We introduce one dimensional sets to help describe and constrain the integral curves of an $n$ dimensional dynamical system. These curves provide more information about the system than the zero-dimensional sets (fixed points) do. In fact, these curves pass through the fixed points. Connecting curves are introduced using two different but equivalent definitions, one from dynamical systems theory, the other from differential geometry. We describe how to compute these curves and illustrate their properties by showing the connecting curves for a number of dynamical systems.
R. Gilmore; Jean-Marc Ginoux; Timothy Jones; C. Letellier; U. S. Freitas
Multiple stage multiple filter hydrate store
An improved hydrate store for a metal halogen battery system is disclosed which employs a multiple stage, multiple filter means for separating the halogen hydrate from the liquid used in forming the hydrate. The filter means is constructed in the form of three separate sections which combine to substantially cover the interior surface of the store container. Exit conduit means is provided in association with the filter means for transmitting liquid passing through the filter means to a hydrate former subsystem. The hydrate former subsystem combines the halogen gas generated during the charging of the battery system with the liquid to form the hydrate in association with the store. Relief valve means is interposed in the exit conduit means for controlling the operation of the separate sections of the filter means, such that the liquid flow through the exit conduit means from each of the separate sections is controlled in a predetermined sequence. The three separate sections of the filter means operate in three discrete stages to provide a substantially uniform liquid flow to the hydrate former subsystem during the charging of the battery system. The separation of the liquid from the hydrate causes an increase in the density of the hydrate by concentrating the hydrate along the filter means. 7 figs.
Bjorkman, H.K. Jr.
Queuing models System dynamics models
models Value chain models Business Model / Organizational Perspective Process Perspective Information#12;#12;#12;#12;Queuing models System dynamics models #12;#12;#12;#12;Blueprint or touchpoint
Glushko, Robert J.
Dynamic systems and subadditive functionals
Consider a problem where a number of dynamic systems are required to travel between points in minimum time. The study of this problem is traditionally divided into two parts: A combinatorial part that assigns points to ...
Itani, Sleiman M
Videos of Experiments from ORNL Gas Hydrate Research
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
Gas hydrate research performed by the Environmental Sciences Division utilizes the ORNL Seafloor Process Simulator, the Parr Vessel, the Sapphire Cell, a fiber optic distributed sensing system, and Raman spectroscopy. The group studies carbon sequestration in the ocean, desalination, gas hydrates in the solar system, and nucleation and dissociation kinetics. The videos available at the gas hydrates website are very short clips from experiments.
Increasing gas hydrate formation temperature for desalination of high salinity produced water with secondary guests
We suggest a new gas hydrate-based desalination process using water-immiscible hydrate formers; cyclopentane (CP) and cyclohexane (CH) as secondary hydrate guests to alleviate temperature requirements for hydrate formation. The hydrate formation reactions were carried out in an isobaric condition of 3.1 MPa to find the upper temperature limit of CO2 hydrate formation. Simulated produced water (8.95 wt % salinity) mixed with the hydrate formers shows an increased upper temperature limit from ?2 �C for simple CO2 hydrate to 16 and 7 �C for double (CO2 + CP) and (CO2 + CH) hydrates, respectively. The resulting conversion rate to double hydrate turned out to be similar to that with simple CO2 hydrate at the upper temperature limit. Hydrate formation rates (Rf) for the double hydrates with CP and CH are shown to be 22 and 16 times higher, respectively, than that of the simple CO2 hydrate at the upper temperature limit. Such mild hydrate formation temperature and fast formation kinetics indicate increased energy efficiency of the double hydrate system for the desalination process. Dissociated water from the hydrates shows greater than 90% salt removal efficiency for the hydrates with the secondary guests, which is also improved from about 70% salt removal efficiency for the simple hydrates.
Cha, Jong-Ho [ORISE; Seol, Yongkoo [U.S. DOE
Hydrate-phobic surfaces
Clathrate hydrate formation and subsequent plugging of deep-sea oil and gas pipelines represent a significant bottleneck for ultra deep-sea production. Current methods for hydrate mitigation focus on injecting thermodynamic ...
Smith, Jonathan David, S.M. Massachusetts Institute of Technology
Towards a Hybrid Dynamic Logic for Hybrid Dynamic Systems1
HyLo 2006 Towards a Hybrid Dynamic Logic for Hybrid Dynamic Systems1 Andr´e Platzer2 Carnegie firstname.lastname@example.com Abstract We introduce a hybrid variant of a dynamic logic for this extended hybrid dynamic logic. With the addition of satisfaction operators, this hybrid logic provides
Platzer, André
Dynamical systems probabilistic risk assessment.
Probabilistic Risk Assessment (PRA) is the primary tool used to risk-inform nuclear power regulatory and licensing activities. Risk-informed regulations are intended to reduce inherent conservatism in regulatory metrics (e.g., allowable operating conditions and technical specifications) which are built into the regulatory framework by quantifying both the total risk profile as well as the change in the risk profile caused by an event or action (e.g., in-service inspection procedures or power uprates). Dynamical Systems (DS) analysis has been used to understand unintended time-dependent feedbacks in both industrial and organizational settings. In dynamical systems analysis, feedback loops can be characterized and studied as a function of time to describe the changes to the reliability of plant Structures, Systems and Components (SSCs). While DS has been used in many subject areas, some even within the PRA community, it has not been applied toward creating long-time horizon, dynamic PRAs (with time scales ranging between days and decades depending upon the analysis). Understanding slowly developing dynamic effects, such as wear-out, on SSC reliabilities may be instrumental in ensuring a safely and reliably operating nuclear fleet. Improving the estimation of a plant's continuously changing risk profile will allow for more meaningful risk insights, greater stakeholder confidence in risk insights, and increased operational flexibility.
Denman, Matthew R.; Ames, Arlo Leroy
In situ apparatus for the study of clathrate hydrates relevant to solar system bodies using synchrotron X-ray diffraction and Raman spectroscopy
Clathrate hydrates are believed to play a significant role in various solar system environments, e.g. comets, and the surfaces and interiors of icy satellites, however the structural factors governing their formation and dissociation are poorly understood. We demonstrate the use of a high pressure gas cell, combined with variable temperature cooling and time-resolved data collection, to the in situ study of clathrate hydrates under conditions relevant to solar system environments. Clathrates formed and processed within the cell are monitored in situ using synchrotron X-ray powder diffraction and Raman spectroscopy. X-ray diffraction allows the formation of clathrate hydrates to be observed as CO2 gas is applied to ice formed within the cell. Complete conversion is obtained by annealing at temperatures just below the ice melting point. A subsequent rise in the quantity of clathrate is observed as the cell is thermally cycled. Four regions between 100-5000cm-1 are present in the Raman spectra that carry feature...
Day, Sarah J; Evans, Aneurin; Parker, Julia E
Opacity reduction using hydrated lime injection
The purpose of this investigation is to study the effects of injecting dry hydrated lime into flue gas to reduce sulfur trioxide (SO{sub 3}) concentrations and consequently stack opacity at the University of Missouri, Columbia power plant. Burning of high sulfur coal (approx. 4% by weight) at the power plant resulted in opacity violations. The opacity problem was due to sulfuric acid mist (H{sub 2}SO{sub 4}) forming at the stack from high SO{sub 3} concentrations. As a result of light scattering by the mist, a visible plume leaves the stack. Therefore, reducing high concentrations of SO{sub 3} reduces the sulfuric acid mist and consequently the opacity problem. The current hydrated lime injection system has reduced the opacity to acceptable limits. To reduce SO{sub 3} concentrations, dry hydrated lime is injected into the flue gas upstream of a particulate collection device (baghouse) and downstream of the induced draft fan. The lime is periodically injected into the flue via a pneumatic piping system. The hydrated lime is transported down the flue and deposited on the filter bags in the baghouse. As the hydrated lime is deposited on the bags a filter cake is established. The reaction between the SO{sub 3} and the hydrated lime takes place on the filter bags. The hydrated lime injection system has resulted in at least 95% reduction in the SO{sub 3} concentration. Low capital equipment requirements and operating cost coupled with easy installation and maintenance makes the system very attractive to industries with similar problems. This paper documents the hydrated lime injection system and tests the effectiveness of the system on SO{sub 3} removal and subsequent opacity reduction. Measurements Of SO{sub 3} concentrations, flue gas velocities, and temperatures have been performed at the duct work and baghouse. A complete analysis of the hydrated lime injection system is provided.
Wolf, D.E.; Seaba, J.P. [Univ. of Missouri, Columbia, MO (United States)
Hydration of the lower stratosphere by ice crystal geysers over land convective systems
The possible impact of deep convective overshooting over land has been explored by six simultaneous soundings of water vapour, particles and ozone in the lower stratosphere next to Mesoscale Convective Systems (MCSs) during ...
Khaykin, S.
Dynamical Systems and Applications of Nonlinear Functional Analysis to Dynamical Systems
Dynamical Systems and Applications of Nonlinear Functional Analysis to Dynamical Systems Meirong consists of three parts. In Part 1 we introduce some basic concepts in dynamical systems, including limit sets, nonwandering sets, topological conjugacy, clas- sification of discrete dynamical systems under
Zhang, Meirong
Relation Between the Widom Line and the Dynamic Crossover in Bulk Water and in Protein Hydration Water
are the derivatives of the state functions with respect to temperature [e.g., isobaric heat capacity CP (H/T)P ] have displaying a liquid-liquid critical point, the relation between changes in dynamic and thermodynamic anomalies arising from the presence of the liquid-liquid critical point. We find a correlation between
Stanley, H. Eugene
Kinetic Theory of Dynamical Systems
It is generally believed that the dynamics of simple fluids can be considered to be chaotic, at least to the extent that they can be modeled as classical systems of particles interacting with short range, repulsive forces. Here we give a brief introduction to those parts of chaos theory that are relevant for understanding some features of non-equilibrium processes in fluids. We introduce the notions of Lyapunov exponents, Kolmogorov-Sinai entropy and related quantities using some simple low-dimensional systems as "toy" models of the more complicated systems encountered in the study of fluids. We then show how familiar methods used in the kinetic theory of gases can be employed for explicit, analytical calculations of the largest Lyapunov exponent and KS entropy for dilute gases composed of hard spheres in d dimensions. We conclude with a brief discussion of interesting, open problems.
R. van Zon; H. van Beijeren; J. R. Dorfman
Methane Hydrate Field Program
This final report document summarizes the activities undertaken and the output from three primary deliverables generated during this project. This fifteen month effort comprised numerous key steps including the creation of an international methane hydrate science team, determining and reporting the current state of marine methane hydrate research, convening an international workshop to collect the ideas needed to write a comprehensive Marine Methane Hydrate Field Research Plan and the development and publication of that plan. The following documents represent the primary deliverables of this project and are discussed in summary level detail in this final report. � Historical Methane Hydrate Project Review Report � Methane Hydrate Workshop Report � Topical Report: Marine Methane Hydrate Field Research Plan � Final Scientific/Technical Report
Thermal stability of certain hydrated phases in systems made using portland cement. Final report
As part of the study of hydraulic-cement system for use in possible underground isolation of nuclear wastes, this study was made to determine the temperature stability of ettringite and chloroaluminate. Either or both of these phases may be expected in a hydraulic cement system depending on the presence of salt (NaCl). The study of ettringite was made using 15 mixtures that contained portland cement, plaster, 2 levels of water, and in some mixtures, 1 of 6 pozzolans (3 fly ashes, 1 slag, a silica fume, a natural pozzolan), plus a 16th mixture with anhydrous sodium sulfate replacing plaster (CaSO4 . 1/2H20). Specimens were made and stored at 23, 50, and 75 C or 23, 75, and 100 C (all four temperatures in one case) for periodic examination by x-ray diffraction for phase compositiion and ettringite stability, and testing for compressive strength and restrained expansion. A more limited study of the stability of chloroaluminate was made along the same lines using fewer mixtures, salt instead of plaster, and higher temperatures plus some pressure. It was found that while some ettringette was decomposed at 75 C, depending on the composition of the mixture, all ettringite was undetectable by x-ray diffraction at 100 C, usually within a few days. The evidence indicates that the ettringite became amorphous and no significant test phases formed in its place. Since there was no corresponding loss in strength or reduction in volume, this loss of ettringite crystallinity was considered to be damaging. Based on much more limited data, chloroaluminate was found to decompose between 130 C at 25 psi and 170 C at 100 psi; no significant phases replaced it.
Buck, A.D.; Burkes, J.P.; Poole, T.S.
Gas Hydrate Storage of Natural Gas
Environmental and economic benefits could accrue from a safe, above-ground, natural-gas storage process allowing electric power plants to utilize natural gas for peak load demands; numerous other applications of a gas storage process exist. A laboratory study conducted in 1999 to determine the feasibility of a gas-hydrates storage process looked promising. The subsequent scale-up of the process was designed to preserve important features of the laboratory apparatus: (1) symmetry of hydrate accumulation, (2) favorable surface area to volume ratio, (3) heat exchanger surfaces serving as hydrate adsorption surfaces, (4) refrigeration system to remove heat liberated from bulk hydrate formation, (5) rapid hydrate formation in a non-stirred system, (6) hydrate self-packing, and (7) heat-exchanger/adsorption plates serving dual purposes to add or extract energy for hydrate formation or decomposition. The hydrate formation/storage/decomposition Proof-of-Concept (POC) pressure vessel and supporting equipment were designed, constructed, and tested. This final report details the design of the scaled POC gas-hydrate storage process, some comments on its fabrication and installation, checkout of the equipment, procedures for conducting the experimental tests, and the test results. The design, construction, and installation of the equipment were on budget target, as was the tests that were subsequently conducted. The budget proposed was met. The primary goal of storing 5000-scf of natural gas in the gas hydrates was exceeded in the final test, as 5289-scf of gas storage was achieved in 54.33 hours. After this 54.33-hour period, as pressure in the formation vessel declined, additional gas went into the hydrates until equilibrium pressure/temperature was reached, so that ultimately more than the 5289-scf storage was achieved. The time required to store the 5000-scf (48.1 hours of operating time) was longer than designed. The lower gas hydrate formation rate is attributed to a lower heat transfer rate in the internal heat exchanger than was designed. It is believed that the fins on the heat-exchanger tubes did not make proper contact with the tubes transporting the chilled glycol, and pairs of fins were too close for interior areas of fins to serve as hydrate collection sites. A correction of the fabrication fault in the heat exchanger fin attachments could be easily made to provide faster formation rates. The storage success with the POC process provides valuable information for making the process an economically viable process for safe, aboveground natural-gas storage.
Rudy Rogers; John Etheridge
World-Systems as Dynamic Networks
World-Systems as Dynamic Networks Christopher Chase-Dunn Institute for Research on World-Systems on comparative world-systems for the workshop on `analyzing complex macrosystems as dynamic networks" at the Santa Fe Institute, April 29- 30, 2004. (8341 words) v. 4-22-04 1 #12;The comparative world-systems
White, Douglas R.
Detection and Production of Methane Hydrate
This project seeks to understand regional differences in gas hydrate systems from the perspective of as an energy resource, geohazard, and long-term climate influence. Specifically, the effort will: (1) collect data and conceptual models that targets causes of gas hydrate variance, (2) construct numerical models that explain and predict regional-scale gas hydrate differences in 2-dimensions with minimal 'free parameters', (3) simulate hydrocarbon production from various gas hydrate systems to establish promising resource characteristics, (4) perturb different gas hydrate systems to assess potential impacts of hot fluids on seafloor stability and well stability, and (5) develop geophysical approaches that enable remote quantification of gas hydrate heterogeneities so that they can be characterized with minimal costly drilling. Our integrated program takes advantage of the fact that we have a close working team comprised of experts in distinct disciplines. The expected outcomes of this project are improved exploration and production technology for production of natural gas from methane hydrates and improved safety through understanding of seafloor and well bore stability in the presence of hydrates. The scope of this project was to more fully characterize, understand, and appreciate fundamental differences in the amount and distribution of gas hydrate and how this would affect the production potential of a hydrate accumulation in the marine environment. The effort combines existing information from locations in the ocean that are dominated by low permeability sediments with small amounts of high permeability sediments, one permafrost location where extensive hydrates exist in reservoir quality rocks and other locations deemed by mutual agreement of DOE and Rice to be appropriate. The initial ocean locations were Blake Ridge, Hydrate Ridge, Peru Margin and GOM. The permafrost location was Mallik. Although the ultimate goal of the project was to understand processes that control production potential of hydrates in marine settings, Mallik was included because of the extensive data collected in a producible hydrate accumulation. To date, such a location had not been studied in the oceanic environment. The project worked closely with ongoing projects (e.g. GOM JIP and offshore India) that are actively investigating potentially economic hydrate accumulations in marine settings. The overall approach was fivefold: (1) collect key data concerning hydrocarbon fluxes which is currently missing at all locations to be included in the study, (2) use this and existing data to build numerical models that can explain gas hydrate variance at all four locations, (3) simulate how natural gas could be produced from each location with different production strategies, (4) collect new sediment property data at these locations that are required for constraining fluxes, production simulations and assessing sediment stability, and (5) develop a method for remotely quantifying heterogeneities in gas hydrate and free gas distributions. While we generally restricted our efforts to the locations where key parameters can be measured or constrained, our ultimate aim was to make our efforts universally applicable to any hydrate accumulation.
George Hirasaki; Walter Chapman; Gerald Dickens; Colin Zelt; Brandon Dugan; Kishore Mohanty; Priyank Jaiswal
Kinetic limits of dynamical systems
Since the pioneering work of Maxwell and Boltzmann in the 1860s and 1870s, a major challenge in mathematical physics has been the derivation of macroscopic evolution equations from the fundamental microscopic laws of classical or quantum mechanics. Macroscopic transport equations lie at the heart of many important physical theories, including fluid dynamics, condensed matter theory and nuclear physics. The rigorous derivation of macroscopic transport equations is thus not only a conceptual exercise that establishes their consistency with the fundamental laws of physics: the possibility of finding deviations and corrections to classical evolution equations makes this subject both intellectually exciting and relevant in practical applications. The plan of these lectures is to develop a renormalisation technique that will allow us to derive transport equations for the kinetic limits of two classes of simple dynamical systems, the Lorentz gas and kicked Hamiltonians (or linked twist maps). The technique uses the ergodic theory of flows on homogeneous spaces (homogeneous flows for short), and is based on joint work with Andreas Str\\"ombergsson.
Jens Marklof
Chemically reacting plumes, gas hydrate dissociation and dendrite solidification
II Gas hydrates Introductionto gas hydrates . . . . . . . . . . 1.127 Gas hydrate dissociation in porous media . 1.
Conroy, Devin Thomas
September 11, 2008 12:55 Dynamical Systems monotonereacs Dynamical Systems
September 11, 2008 12:55 Dynamical Systems monotonereacs Dynamical Systems Vol. 00, No. 00, Month 200x, 130 RESEARCH ARTICLE Monotonicity in chemical reaction systems Murad Banajia, a Department) This paper discusses the question of when the dynamical systems arising from chemical reac- tion networks
Banaji,. Murad
The structure of tame minimal dynamical systems
A dynamical version of the Bourgain-Fremlin-Talagrand dichotomy shows that the enveloping semigroup of a dynamical system is either very large and contains a topological copy of $\\beta \\N$, or it is a "tame" topological space whose topology is determined by the convergence of sequences. In the latter case the dynamical system is called tame. We use the structure theory of minimal dynamical systems to show that, when the acting group is Abelian, a tame metric minimal dynamical system (i) is almost automorphic (i.e. it is an almost 1-1 extension of an equicontinuous system), and (ii) admits a unique invariant probability measure such that the corresponding measure preserving system is measure theoretically isomorphic to the Haar measure system on the maximal equicontinuous factor.
Eli Glasner
Zeno Dynamics for Open Quantum Systems
In this paper we formulate limit Zeno dynamics of general open systems as the adiabatic elimination of fast components. We are able to exploit previous work on adiabatic elimination of quantum stochastic models to give explicitly the conditions under which open Zeno dynamics will exist. The open systems formulation is further developed as a framework for Zeno master equations, and Zeno filtering (that is, quantum trajectories based on a limit Zeno dynamical model). We discuss several models from the point of view of quantum control. For the case of linear quantum stochastic systems we present a condition for stability of the asymptotic Zeno dynamics.
J. E. Gough
Effect of under-inhibition with methanol and ethylene glycol on the hydrate control process
Hydrate control can be achieved by chemical injection. Currently, methanol and ethylene glycol are the most widely used inhibitors in offshore hydrate control operations. To achieve effective hydrate inhibition, a sufficient amount of inhibitor must be injected to shift the thermodynamic equilibrium condition for hydrate formation outside the pipeline operating pressure and temperature. Recently published field experiments showed that hydrate blockages form more readily in under-inhibited systems than in systems completely without inhibitor. A laboratory study is conducted to determine the effect of low concentration (1--5wt%) methanol and ethylene glycol on the hydrate formation process. The results show that, although these chemicals are effective hydrate inhibitors when added in sufficient quantities, they actually enhance the rate of hydrate formation when added at low concentrations to the water. Furthermore, the presence of these chemicals seems to affect the size of the forming hydrate particles.
Yousif, M.H.
X-ray Scanner for ODP Leg 204: Drilling Gas Hydrates on Hydrate Ridge, Cascadia Continental Margin
International Conference of Gas Hydrates, Yokohama, Japan.Prospectus, Drilling Gas Hydrates On Hydrate Ridge, CascadiaLeg 204: Drilling Gas Hydrates on Hydrate Ridge, Cascadia
Freifeld, Barry; Kneafsey, Tim; Pruess, Jacob; Reiter, Paul; Tomutsa, Liviu
Methane Hydrate Program
Program Report to Congress | Page 13 Hutchinson, D., Ruppel, C., Roberts, H., Carney, R., Smith, M., 2011. Gas hydrates in the Gulf of Mexico. In Gulf of Mexico Origin, Waters, and...
Fe-containing phases in hydrated cements
In this study synchrotron X-ray absorption spectroscopy (XAS) has been applied, an element specific technique which allows Fe-containing phases to be identified in the complex mineral mixture of hydrated cements. Several Fe species contributed to the overall Fe K-edge spectra recorded on the cement samples. In the early stage of cement hydration ferrite was the dominant Fe-containing mineral. Ferrihydrite was detected during the first hours of the hydration process. After 1 day the formation of Al- and Fe-siliceous hydrogarnet was observed, while the amount of ferrihydrite decreased. The latter finding agrees with thermodynamic modeling, which predicts the formation of Fe-siliceous hydrogarnet in Portland cement systems. The presence of Al- and Fe-containing siliceous hydrogarnet was further substantiated in the residue of hydrated cement by performing a selective dissolution procedure. - Highlights: � Fe bound to ferrihydrite at early age hydration � Fe found to be stable in siliceous hydrogarnet at longer term age hydration � Fe-containing AFt and AFm phases are less stable than siliceous hydrogarnet. � The study demonstrates EXAFS used to identify amorphous or poorly crystalline phases.
Dilnesa, B.Z., E-mail: firstname.lastname@example.com [Empa, Laboratory for Concrete and Construction Chemistry, �berlandstrasse 129, 8600 D�bendorf (Switzerland); Wieland, E. [Paul Scherrer Institute, Laboratory for Waste Management, 5232 Villigen PSI (Switzerland); Lothenbach, B. [Empa, Laboratory for Concrete and Construction Chemistry, �berlandstrasse 129, 8600 D�bendorf (Switzerland); D�hn, R. [Paul Scherrer Institute, Laboratory for Waste Management, 5232 Villigen PSI (Switzerland); Scrivener, K.L. [Ecole Polytechnique Federal de Lausanne (EPFL), Laboratory for Construction Materials, 1015 Lausanne (Switzerland)
Bifurcations and Chaos in Simple Dynamical Systems
Chaos is an active research subject in the fields of science in recent years. it is a complex and an erratic behavior that is possible in very simple systems. in the present day, the chaotic behavior can be observed in experiments. Many studies have been made in chaotic dynamics during the past three decades and many simple chaotic systems have been discovered. in this work-bifurcations and chaos in simple dynamical systems - the behavior of some simple dynamical systems is studied by constructing mathematical models. investigations are made on the periodic orbits for continuous maps and idea of sensitive dependence on initial conditions,which is the hallmark of chaos, is obtained.
Mrs. T. Theivasanthi
Marine electromagnetic methods for gas hydrate characterization
1.2 Gas Hydrates . . . . . . . .1.2.1 Distribution of Gas Hydrates . . . . . . . . . . .1.2.2 Importance of Gas Hydrates . . . . .
Weitemeyer, Karen Andrea
Marine Electromagnetic Methods for Gas Hydrate Characterization
Weitemeyer, Karen A
SIAM conference on applications of dynamical systems
A conference (Oct.15--19, 1992, Snowbird, Utah; sponsored by SIAM (Society for Industrial and Applied Mathematics) Activity Group on Dynamical Systems) was held that highlighted recent developments in applied dynamical systems. The main lectures and minisymposia covered theory about chaotic motion, applications in high energy physics and heart fibrillations, turbulent motion, Henon map and attractor, integrable problems in classical physics, pattern formation in chemical reactions, etc. The conference fostered an exchange between mathematicians working on theoretical issues of modern dynamical systems and applied scientists. This two-part document contains abstracts, conference program, and an author index.
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Protein viscoelastic dynamics: a model system
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.
Craig Fogle; Joseph Rudnick; David Jasnow
Distributed Termination Detection for Dynamic Systems
Distributed Termination Detection for Dynamic Systems D. M. Dhamdhere \\Lambda Sridhar R. Iyer E for detecting the termination of a dis tributed computation is presented. The algorithm does not require global are provided. Keywords Distributed algorithms, Distributed computation, Distributed termination, Dynamic
Dhamdhere, Dhananjay Madhav
Fuel cell membrane hydration and fluid metering
A hydration system includes fuel cell fluid flow plate(s) and injection port(s). Each plate has flow channel(s) with respective inlet(s) for receiving respective portion(s) of a given stream of reactant fluid for a fuel cell. Each injection port injects a portion of liquid water directly into its respective flow channel. This serves to hydrate at least corresponding part(s) of a given membrane of the corresponding fuel cell(s). The hydration system may be augmented by a metering system including flow regulator(s). Each flow regulator meters an injecting at inlet(s) of each plate of respective portions of liquid into respective portion(s) of a given stream of fluid by corresponding injection port(s).
Jones, Daniel O. (Glenville, NY); Walsh, Michael M. (Fairfield, CT)
Generalized dynamical entropies in weakly chaotic systems
A large class of technically non-chaotic systems, involving scatterings of light particles by flat surfaces with sharp boundaries, is nonetheless characterized by complex random looking motion in phase space. For these systems one may define a generalized, Tsallis type dynamical entropy that increases linearly with time. It characterizes a maximal gain of information about the system that increases as a power of time. However, this entropy cannot be chosen independently from the choice of coarse graining lengths and it assigns positive dynamical entropies also to fully integrable systems. By considering these dependencies in detail one usually will be able to distinguish weakly chaotic from fully integrable systems.
Henk van Beijeren
Ecology & Earth Systems Dynamics for Educators
Ecology & Earth Systems Dynamics for Educators July 21-25, 2014 CI 5540-003 (86282) 3 Credits Science and Earth Science curricula in Minnesota public schools. It is designed primarily for middle
Amin, S. Massoud
System dynamics, market microstructure and asset pricing
Traditional asset pricing approaches are not able to explain extreme volatility and tail events that characterized financial markets in the past decade. System Dynamics theory, which is still underutilized in financial ...
Leika, Mindaugas
Stochastic dynamic systems fl T. Soderstrom, 1997
Stochastic dynamic systems Chapter 10 c fl T. S¨oderstr¨om, 1997 1 Optimal stochastic control ffl controllers c fl T. S¨oderstr¨om, 1997 2 Optimal stochastic control some illustrative examples System x¨oderstr¨om, 1997 3 Optimal stochastic control Deterministic system Criterion J = x 2 (N) = [ax(N \\Gamma 1) + bu
Flener, Pierre
Dynamical System Analysis for a phantom model
The paper deals with a dynamical system analysis related to phantom cosmological model . Here gravity is coupled to phantom scalar field having scalar coupling function and a potential. The field equations are reduced to an autonomous dynamical system by a suitable redefinition of the basic variables and assuming some suitable form of the potential function. Finally, critical points are evaluated, their nature have been analyzed and corresponding cosmological scenario has been discussed.
Nilanjana Mahata; Subenoy Chakraborty
Dynamic Algorithm for Space Weather Forecasting System
for the designation as UNDERGRADUATE RESEARCH SCHOLAR April 2010 Major: Nuclear Engineering DYNAMIC ALGORITHM FOR SPACE WEATHER FORECASTING SYSTEM A Junior Scholars Thesis by LUKE DUNCAN FISCHER Submitted to the Office of Undergraduate... 2010 Major: Nuclear Engineering iii ABSTRACT Dynamic Algorithm for Space Weather Forecasting System. (April 2010) Luke Duncan Fischer Department of Nuclear Engineering Texas A&M University Research Advisor: Dr. Stephen Guetersloh...
Fischer, Luke D.
Global Dynamics in Galactic Triaxial Systems I
In this paper we present a theoretical analysis of the global dynamics in a triaxial galactic system using a 3D integrable Hamiltonian as a simple representation. We include a thorough discussion on the effect of adding a generic non--integrable perturbation to the global dynamics of the system. We adopt the triaxial Stackel Hamiltonian as the integrable model and compute its resonance structure in order to understand its global dynamics when a perturbation is introduced. Also do we take profit of this example in order to provide a theoretical discussion about diffussive processes taking place in phase space.
Pablo M. Cincotta; Claudia M. Giordano; Josefa Perez; .
November 18, 2009 22:50 Vehicle System Dynamics VSD09 Vehicle System Dynamics
November 18, 2009 22:50 Vehicle System Dynamics VSD09 Vehicle System Dynamics Vol. 00, No. 00), involving the steering and braking actuators. This VDSC aims at improving automotive vehicle yaw stability the rear wheels) and use the steering actuator only if it is necessary (e.g. if the braking system
FOCUS ISSUE: Nonlinear dynamics related to polymeric systems Overview: Nonlinear dynamics related to polymeric systems
FOCUS ISSUE: Nonlinear dynamics related to polymeric systems Overview: Nonlinear dynamics related to polymeric systems Irving R. Epstein Department of Chemistry, Brandeis University, Waltham, Massachusetts is known about nonlinear phenom- ena in polymeric systems. One reason for the lack of interest in nonlinear
Epstein, Irving R.
Dynamic Impregnator Reactor System (Poster)
IBRF poster developed for the IBRF showcase. Describes the multifarious system designed for complex feedstock impregnation and processing. IBRF feedstock system has several unit operations combined into one robust system that provides for flexible and staged process configurations, such as spraying, soaking, low-severity pretreatment, enzymatic hydrolysis, fermentation, concentration/evaporation, and distillation.
Mechanisms Leading to Co-Existence of Gas Hydrate in Ocean Sediments [Part 2 of 2
In this project we have sought to explain the co-existence of gas and hydrate phases in sediments within the gas hydrate stability zone. We have focused on the gas/brine interface at the scale of individual grains in the sediment. The capillary forces associated with a gas/brine interface play a dominant role in many processes that occur in the pores of sediments and sedimentary rocks. The mechanical forces associated with the same interface can lead to fracture initiation and propagation in hydrate-bearing sediments. Thus the unifying theme of the research reported here is that pore scale phenomena are key to understanding large scale phenomena in hydrate-bearing sediments whenever a free gas phase is present. Our analysis of pore-scale phenomena in this project has delineated three regimes that govern processes in which the gas phase pressure is increasing: fracturing, capillary fingering and viscous fingering. These regimes are characterized by different morphology of the region invaded by the gas. On the other hand when the gas phase pressure is decreasing, the corresponding regimes are capillary fingering and compaction. In this project, we studied all these regimes except compaction. Many processes of interest in hydrate-bearing sediments can be better understood when placed in the context of the appropriate regime. For example, hydrate formation in sub-permafrost sediments falls in the capillary fingering regime, whereas gas invasion into ocean sediments is likely to fall into the fracturing regime. Our research provides insight into the mechanisms by which gas reservoirs are converted to hydrate as the base of the gas hydrate stability zone descends through the reservoir. If the reservoir was no longer being charged, then variation in grain size distribution within the reservoir explain hydrate saturation profiles such as that at Mt. Elbert, where sand-rich intervals containing little hydrate are interspersed between intervals containing large hydrate saturations. Large volumes (of order one pore volume) of gaseous and aqueous phases must be transported into the gas hydrate stability zone. The driver for this transport is the pressure sink induced by a reduction in occupied pore volume that accompanies the formation of hydrate from gas and water. Pore-scale imbibition models and bed-scale multiphase flow models indicate that the rate-limiting step in converting gas to hydrate is the supply of water to the hydrate stability zone. Moreover, the water supply rate is controlled by capillarity-driven flux for conditions typical of the Alaska North Slope. A meter-scale laboratory experiment confirms that significant volumes of fluid phases move into the hydrate stability zone and that capillarity is essential for the water flux. The model shows that without capillarity-driven flux, large saturations of hydrate cannot form. The observations of thick zones of large saturation at Mallik and Mt Elbert thus suggest that the primary control on these systems is the rate of transport of gaseous and aqueous phases, driven by the pressure sink at the base of the gas hydrate stability zone. A key finding of our project is the elucidation of ?capillary fracturing? as a dominant gas transport mechanism in low-permeability media. We initially investigate this phenomenon by means of grain-scale simulations in which we extended a discrete element mechanics code (PFC, by Itasca) to incorporate the dynamics of first singlephase and then multiphase flow. A reductionist model on a square lattice allows us to determine some of the fundamental dependencies of the mode of gas invasion (capillary fingering, viscous fingering, and fracturing) on the parameters of the system. We then show that the morphology of the gas-invaded region exerts a fundamental control on the fabric of methane hydrate formation, and on the overpressures caused by methane hydrate dissociation. We demonstrate the existence of the different invasion regimes by means of controlled laboratory experiments in a radial cell. We collapse the behavior in the form of a phase dia
Bryant, Steven; Juanes, Ruben
Mechanisms Leading to Co-Existence of Gas Hydrate in Ocean Sediments [Part 1 of 2
In this project we have sought to explain the co-existence of gas and hydrate phases in sediments within the gas hydrate stability zone. We have focused on the gas/brine interface at the scale of individual grains in the sediment. The capillary forces associated with a gas/brine interface play a dominant role in many processes that occur in the pores of sediments and sedimentary rocks. The mechanical forces associated with the same interface can lead to fracture initiation and propagation in hydrate-bearing sediments. Thus the unifying theme of the research reported here is that pore scale phenomena are key to understanding large scale phenomena in hydrate-bearing sediments whenever a free gas phase is present. Our analysis of pore-scale phenomena in this project has delineated three regimes that govern processes in which the gas phase pressure is increasing: fracturing, capillary fingering and viscous fingering. These regimes are characterized by different morphology of the region invaded by the gas. On the other hand when the gas phase pressure is decreasing, the corresponding regimes are capillary fingering and compaction. In this project, we studied all these regimes except compaction. Many processes of interest in hydrate-bearing sediments can be better understood when placed in the context of the appropriate regime. For example, hydrate formation in sub-permafrost sediments falls in the capillary fingering regime, whereas gas invasion into ocean sediments is likely to fall into the fracturing regime. Our research provides insight into the mechanisms by which gas reservoirs are converted to hydrate as the base of the gas hydrate stability zone descends through the reservoir. If the reservoir was no longer being charged, then variation in grain size distribution within the reservoir explain hydrate saturation profiles such as that at Mt. Elbert, where sand-rich intervals containing little hydrate are interspersed between intervals containing large hydrate saturations. Large volumes (of order one pore volume) of gaseous and aqueous phases must be transported into the gas hydrate stability zone. The driver for this transport is the pressure sink induced by a reduction in occupied pore volume that accompanies the formation of hydrate from gas and water. Pore-scale imbibition models and bed-scale multiphase flow models indicate that the rate-limiting step in converting gas to hydrate is the supply of water to the hydrate stability zone. Moreover, the water supply rate is controlled by capillarity-driven flux for conditions typical of the Alaska North Slope. A meter-scale laboratory experiment confirms that significant volumes of fluid phases move into the hydrate stability zone and that capillarity is essential for the water flux. The model shows that without capillarity-driven flux, large saturations of hydrate cannot form. The observations of thick zones of large saturation at Mallik and Mt Elbert thus suggest that the primary control on these systems is the rate of transport of gaseous and aqueous phases, driven by the pressure sink at the base of the gas hydrate stability zone. A key finding of our project is the elucidation of ?capillary fracturing? as a dominant gas transport mechanism in low-permeability media. We initially investigate this phenomenon by means of grain-scale simulations in which we extended a discrete element mechanics code (PFC, by Itasca) to incorporate the dynamics of first single-phase and then multiphase flow. A reductionist model on a square lattice allows us to determine some of the fundamental dependencies of the mode of gas invasion (capillary fingering, viscous fingering, and fracturing) on the parameters of the system. We then show that the morphology of the gas-invaded region exerts a fundamental control on the fabric of methane hydrate formation, and on the overpressures caused by methane hydrate dissociation. We demonstrate the existence of the different invasion regimes by means of controlled laboratory experiments in a radial cell. We collapse the behavior in the form of a phase di
Reaction dynamics in polyatomic molecular systems
The goal of this program is the development of theoretical methods and models for describing the dynamics of chemical reactions, with specific interest for application to polyatomic molecular systems of special interest and relevance. There is interest in developing the most rigorous possible theoretical approaches and also in more approximate treatments that are more readily applicable to complex systems.
Miller, W.H. [Lawrence Berkeley Laboratory, CA (United States)
Ion desolvation as a mechanism for kinetic isotope fractionation in aqueous systems
Radnai�T�(1993)�Structure�and�dynamics�of�hydrated�ions. �Radnai�T�(1993)�Structure�and�dynamics�of�hydrated�ions. �Radnai�T�(1993)�Structure�and�dynamics�of�hydrated�ions. �
Hofmann, A.E.
Site Selection for DOE/JIP Gas Hydrate Drilling in the Northern Gulf of Mexico
Studies of geologic and geophysical data from the offshore of India have revealed two geologically distinct areas with inferred gas hydrate occurrences: the passive continental margins of the Indian Peninsula and along the Andaman convergent margin. The Indian National Gas Hydrate Program (NGHP) Expedition 01 was designed to study the occurrence of gas hydrate off the Indian Peninsula and along the Andaman convergent margin with special emphasis on understanding the geologic and geochemical controls on the occurrence of gas hydrate in these two diverse settings. NGHP Expedition 01 established the presence of gas hydrates in Krishna- Godavari, Mahanadi and Andaman basins. The expedition discovered one of the richest gas hydrate accumulations yet documented (Site 10 in the Krishna-Godavari Basin), documented the thickest and deepest gas hydrate stability zone yet known (Site 17 in Andaman Sea), and established the existence of a fully-developed gas hydrate system in the Mahanadi Basin (Site 19).
Collett, T.S. (USGS); Riedel, M. (McGill Univ., Montreal, Quebec, Canada); Cochran, J.R. (Columbia Univ., Palisades, NY); Boswell, R.M.; Kumar, Pushpendra (Oil and Natural Gas Corporation Ltd., Navi Mumbai, India); Sathe, A.V. (Oil and Natural Gas Corporation Ltd., Uttaranchal, INDIA)
Robust services in dynamic systems
Our growing reliance on online services accessible on the Internet demands highly- available systems that work correctly without interruption. This thesis extends previous work on Byzantine-fault-tolerant replication to ...
Rodrigues, Rodrigo Seromenho Miragaia, 1975-
Investigating the Metastability of Clathrate Hydrates for Energy Storage
Important breakthrough discoveries have been achieved from the DOE award on the key processes controlling the synthesis and structure-property relations of clathrate hydrates, which are critical to the development of clathrate hydrates as energy storage materials. Key achievements include: (i) the discovery of key clathrate hydrate building blocks (stable and metastable) leading to clathrate hydrate nucleation and growth; (ii) development of a rapid clathrate hydrate synthesis route via a seeding mechanism; (iii) synthesis-structure relations of H2 + CH4/CO2 binary hydrates to control thermodynamic requirements for energy storage and sequestration applications; (iv) discovery of a new metastable phase present during clathrate hydrate structural transitions. The success of our research to-date is demonstrated by the significant papers we have published in high impact journals, including Science, Angewandte Chemie, J. Am. Chem. Soc. Intellectual Merits of Project Accomplishments: The intellectual merits of the project accomplishments are significant and transformative, in which the fundamental coupled computational and experimental program has provided new and critical understanding on the key processes controlling the nucleation, growth, and thermodynamics of clathrate hydrates containing hydrogen, methane, carbon dioxide, and other guest molecules for energy storage. Key examples of the intellectual merits of the accomplishments include: the first discovery of the nucleation pathways and dominant stable and metastable structures leading to clathrate hydrate formation; the discovery and experimental confirmation of new metastable clathrate hydrate structures; the development of new synthesis methods for controlling clathrate hydrate formation and enclathration of molecular hydrogen. Broader Impacts of Project Accomplishments: The molecular investigations performed in this project on the synthesis (nucleation & growth)-structure-stability relations of clathrate hydrate systems are pivotal in the fundamental understanding of crystalline clathrate hydrates and the discovery of new clathrate hydrate properties and novel materials for a broad spectrum of energy applications, including: energy storage (hydrogen, natural gas); carbon dioxide sequestration; controlling hydrate formation in oil/gas transportation in subsea pipelines. The Project has also enabled the training of undergraduate, graduate and postdoctoral students in computational methods, molecular spectroscopy and diffraction, and measurement methods at extreme conditions of high pressure and low temperature.
Koh, Carolyn Ann [Colorado School of Mines
Calcium-Silicate-Hydrate in cementitious systems : chemomechanical correlations, extreme temperature behavior, and kinetics and morphology of in-situ formation
Concrete, the second most used material on the planet, is a multi-scale heterogeneous material. A fundamental component known as Calcium-Silicate-Hydrate which forms from the reaction between cement and water is the binding ...
Jagannathan, Deepak
Very Large System Dynamics Models - Lessons Learned
This paper provides lessons learned from developing several large system dynamics (SD) models. System dynamics modeling practice emphasize the need to keep models small so that they are manageable and understandable. This practice is generally reasonable and prudent; however, there are times that large SD models are necessary. This paper outlines two large SD projects that were done at two Department of Energy National Laboratories, the Idaho National Laboratory and Sandia National Laboratories. This paper summarizes the models and then discusses some of the valuable lessons learned during these two modeling efforts.
Jacob J. Jacobson; Leonard Malczynski
Thermodynamic formalism for systems with Markov dynamics
The thermodynamic formalism allows one to access the chaotic properties of equilibrium and out-of-equilibrium systems, by deriving those from a dynamical partition function. The definition that has been given for this partition function within the framework of discrete time Markov chains was not suitable for continuous time Markov dynamics. Here we propose another interpretation of the definition that allows us to apply the thermodynamic formalism to continuous time. We also generalize the formalism --a dynamical Gibbs ensemble construction-- to a whole family of observables and their associated large deviation functions. This allows us to make the connection between the thermodynamic formalism and the observable involved in the much-studied fluctuation theorem. We illustrate our approach on various physical systems: random walks, exclusion processes, an Ising model and the contact process. In the latter cases, we identify a signature of the occurrence of dynamical phase transitions. We show that this signature can already be unravelled using the simplest dynamical ensemble one could define, based on the number of configuration changes a system has undergone over an asymptotically large time window.
Vivien Lecomte; C�cile Appert-Rolland; Fr�d�ric van Wijland
Design tools for complex dynamic security systems.
The development of tools for complex dynamic security systems is not a straight forward engineering task but, rather, a scientific task where discovery of new scientific principles and math is necessary. For years, scientists have observed complex behavior but have had difficulty understanding it. Prominent examples include: insect colony organization, the stock market, molecular interactions, fractals, and emergent behavior. Engineering such systems will be an even greater challenge. This report explores four tools for engineered complex dynamic security systems: Partially Observable Markov Decision Process, Percolation Theory, Graph Theory, and Exergy/Entropy Theory. Additionally, enabling hardware technology for next generation security systems are described: a 100 node wireless sensor network, unmanned ground vehicle and unmanned aerial vehicle.
Byrne, Raymond Harry; Rigdon, James Brian; Rohrer, Brandon Robinson; Laguna, Glenn A.; Robinett, Rush D. III (.; ); Groom, Kenneth Neal; Wilson, David Gerald; Bickerstaff, Robert J.; Harrington, John J.
Quintessence Scalar Field: A Dynamical Systems Study
The present work deals with a dynamical systems study of quintessence potentials leading to the present accelerated expansion of the universe. The principal interest is to check for late time attractors which give an accelerated expansion for the universe. Two examples are worked out, namely the exponential and the power-law potentials.
Nandan Roy; Narayan Banerjee
Conservation Laws and Lumped System Dynamics
Conservation Laws and Lumped System Dynamics A.J. van der Schaft, B.M. Maschke 1 Introduction which is directly based on conservation laws. Modeling based on conservation laws is prevalent for electrical circuits is the circuit graph we will show in this paper how distributed-parameter conservation
Schaft, Arjan van der
Stochastic dynamic systems Chapter 5 c fl T. S¨oderstr¨om, 1997 1 Optimal estimation ffl The conditional mean ffl Best linear estimate ffl ML estimation c fl T. S¨oderstr¨om, 1997 2 Optimal estimation criterion 2. Symmetric cond pdf c fl T. S¨oderstr¨om, 1997 3 Best linear estimate Given Ex = mx ; Ey = my E
Dynamic Positioning Systems Usability and Interaction Styles
started offshore- drilling in search of larger deposits of oil. With this, a new generation of vessels on interaction with Dynamic Positioning Systems (DP) and how new interaction styles can be introduced to make/multi-touch combined with hand-gestures to create a new type of user-experience. The aim for this research
Dunlop, Mark D.
Dynamical real numbers and living systems
Recently uncovered second derivative discontinuous solutions of the simplest linear ordinary differential equation define not only an nonstandard extension of the framework of the ordinary calculus, but also provide a dynamical representation of the ordinary real number system. Every real number can be visualized as a living cell -like structure, endowed with a definite evolutionary arrow. We discuss the relevance of this extended calculus in the study of living systems. We also present an intelligent version of the Newton's first law of motion.
Dhurjati Prasad Datta
Rapid gas hydrate formation process
The disclosure provides a method and apparatus for forming gas hydrates from a two-phase mixture of water and a hydrate forming gas. The two-phase mixture is created in a mixing zone which may be wholly included within the body of a spray nozzle. The two-phase mixture is subsequently sprayed into a reaction zone, where the reaction zone is under pressure and temperature conditions suitable for formation of the gas hydrate. The reaction zone pressure is less than the mixing zone pressure so that expansion of the hydrate-forming gas in the mixture provides a degree of cooling by the Joule-Thompson effect and provides more intimate mixing between the water and the hydrate-forming gas. The result of the process is the formation of gas hydrates continuously and with a greatly reduced induction time. An apparatus for conduct of the method is further provided.
Brown, Thomas D.; Taylor, Charles E.; Unione, Alfred J.
Chaotic properties of systems with Markov dynamics
We present a general approach for computing the dynamic partition function of a continuous-time Markov process. The Ruelle topological pressure is identified with the large deviation function of a physical observable. We construct for the first time a corresponding finite Kolmogorov-Sinai entropy for these processes. Then, as an example, the latter is computed for a symmetric exclusion process. We further present the first exact calculation of the topological pressure for an N-body stochastic interacting system, namely an infinite-range Ising model endowed with spin-flip dynamics. Expressions for the Kolmogorov-Sinai and the topological entropies follow.
Vivien Lecomte; Cecile Appert-Rolland; Frederic van Wijland
Spatiotemporal dynamics in a spatial plankton system
In this paper, we investigate the complex dynamics of a spatial plankton-fish system with Holling type III functional responses. We have carried out the analytical study for both one and two dimensional system in details and found out a condition for diffusive instability of a locally stable equilibrium. Furthermore, we present a theoretical analysis of processes of pattern formation that involves organism distribution and their interaction of spatially distributed population with local diffusion. The results of numerical simulations reveal that, on increasing the value of the fish predation rates, the sequences spots $\\rightarrow$ spot-stripe mixtures$\\rightarrow$ stripes$\\rightarrow$ hole-stripe mixtures holes$\\rightarrow$ wave pattern is observed. Our study shows that the spatially extended model system has not only more complex dynamic patterns in the space, but also has spiral waves.
Ranjit Kumar Upadhyay; Weiming Wang; N. K. Thakur
Dynamics of heat transfer between nano systems
We develop a dynamical theory of heat transfer between two nano systems. In particular, we consider the resonant heat transfer between two nanoparticles due to the coupling of localized surface modes having a finite spectral width. We model the coupled nanosystem by two coupled quantum mechanical oscillators, each interacting with its own heat bath, and obtain a master equation for the dynamics of heat transfer. The damping rates in the master equation are related to the lifetimes of localized plasmons in the nanoparticles. We study the dynamics towards the steady state and establish connection with the standard theory of heat transfer in steady state. For strongly coupled nano particles we predict Rabi oscillations in the mean occupation number of surface plasmons in each nano particle.
Svend-Age Biehs; Girish S. Agarwal
Abstract The concurrent goals of cement hydration are to percolate (bridge) the original
Cement hydration �? Low temperature calorimetry �? Microstructure �? Percolation �? Porosity �? Rheology �?, however, cement-based materials exhibit a highly dynamic (micro)structure that is extremely sen- sitive. Because many of the cement hydration prod- ucts form around the initial cement clinker par- ticles
Bentz, Dale P.
methane hydrate science plan-final.indd
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
2013 Principal Authors: Consor um for Ocean Leadership and the Methane Hydrate Project Science Team December 2013 DOE Award Number: DE-FE0010195 Project Title: Methane Hydrate...
Stochastic dynamic systems Chapter 2 c fl T. S¨oderstr¨om, 1997 1 Some probability theory ffl Basic facts ffl Conditional distributions ffl Complexvalued Gaussian variables c fl T. S¨oderstr¨om, 1997 2) increasing ffl limx!1 F(x) = 1 ffl lim x!\\Gamma1 F (x) = 0 c fl T. S¨oderstr¨om, 1997 3 Random variables
4, 9931057, 2007 Methane hydrate
BGD 4, 9931057, 2007 Methane hydrate stability and anthropogenic climate change D. Archer Title Discussions Biogeosciences Discussions is the access reviewed discussion forum of Biogeosciences Methane 2007 Correspondence to: D. Archer (email@example.com) 993 #12;BGD 4, 9931057, 2007 Methane hydrate
Quantitative Adaptation Analytics for Assessing Dynamic Systems of Systems.
Our society is increasingly reliant on systems and interoperating collections of systems, known as systems of systems (SoS). These SoS are often subject to changing missions (e.g., nation- building, arms-control treaties), threats (e.g., asymmetric warfare, terrorism), natural environments (e.g., climate, weather, natural disasters) and budgets. How well can SoS adapt to these types of dynamic conditions? This report details the results of a three year Laboratory Directed Research and Development (LDRD) project aimed at developing metrics and methodologies for quantifying the adaptability of systems and SoS. Work products include: derivation of a set of adaptability metrics, a method for combining the metrics into a system of systems adaptability index (SoSAI) used to compare adaptability of SoS designs, development of a prototype dynamic SoS (proto-dSoS) simulation environment which provides the ability to investigate the validity of the adaptability metric set, and two test cases that evaluate the usefulness of a subset of the adaptability metrics and SoSAI for distinguishing good from poor adaptability in a SoS. Intellectual property results include three patents pending: A Method For Quantifying Relative System Adaptability, Method for Evaluating System Performance, and A Method for Determining Systems Re-Tasking.
Gauthier, John H.; Miner, Nadine E.; Wilson, Michael L.; Le, Hai D.; Kao, Gio K; Melander, Darryl J.; Longsine, Dennis Earl [Sandia National Laboratories, Unknown, Unknown; Vander Meer, Robert Charles,
Heat flux dynamics in dissipative cascaded systems
We study the dynamics of heat flux in the thermalization process of a pair of identical quantum system that interact dissipatively with a reservoir in a {\\it cascaded} fashion. Despite the open dynamics of the bipartite system S is globally Lindbladian, one of the subsystems "sees" the reservoir in a state modified by the interaction with the other subsystem and hence it undergoes a non-Markovian dynamics. As a consequence, the heat flow exhibits a non-exponential time behaviour which can greatly deviate from the case where each party is independently coupled to the reservoir. We investigate both thermal and correlated initial states of $S$ and show that the presence of correlations at the beginning can considerably affect the heat flux rate. We carry out our study in two paradigmatic cases -- a pair of harmonic oscillators with a reservoir of bosonic modes and two qubits with a reservoir of fermionic modes -- and compare the corresponding behaviours. In the case of qubits and for initial thermal states, we find that the trace distance discord is at any time interpretable as the correlated contribution to the total heat flux.
Salvatore Lorenzo; Alessandro Farace; Francesco Ciccarello; G. Massimo Palma; Vittorio Giovannetti
Wind turbine control systems: Dynamic model development using system identification and the fast structural dynamics code
Mitigating the effects of damaging wind turbine loads and responses extends the lifetime of the turbine and, consequently, reduces the associated Cost of Energy (COE). Active control of aerodynamic devices is one option for achieving wind turbine load mitigation. Generally speaking, control system design and analysis requires a reasonable dynamic model of {open_quotes}plant,{close_quotes} (i.e., the system being controlled). This paper extends the wind turbine aileron control research, previously conducted at the National Wind Technology Center (NWTC), by presenting a more detailed development of the wind turbine dynamic model. In prior research, active aileron control designs were implemented in an existing wind turbine structural dynamics code, FAST (Fatigue, Aerodynamics, Structures, and Turbulence). In this paper, the FAST code is used, in conjunction with system identification, to generate a wind turbine dynamic model for use in active aileron control system design. The FAST code is described and an overview of the system identification technique is presented. An aileron control case study is used to demonstrate this modeling technique. The results of the case study are then used to propose ideas for generalizing this technique for creating dynamic models for other wind turbine control applications.
Stuart, J.G.; Wright, A.D.; Butterfield, C.P.
Dynamically stable magnetic suspension/bearing system
A magnetic bearing system contains magnetic subsystems which act together to support a rotating element in a state of dynamic equilibrium. However, owing to the limitations imposed by Earnshaw's Theorem, the magnetic bearing systems to be described do not possess a stable equilibrium at zero rotational speed. Therefore, mechanical stabilizers are provided, in each case, to hold the suspended system in equilibrium until its speed has exceeded a low critical speed where dynamic effects take over, permitting the achievement of a stable equilibrium for the rotating object. A state of stable equilibrium is achieved above a critical speed by use of a collection of passive elements using permanent magnets to provide their magnetomotive excitation. The magnetic forces exerted by these elements, when taken together, levitate the rotating object in equilibrium against external forces, such as the force of gravity or forces arising from accelerations. At the same time, this equilibrium is made stable against displacements of the rotating object from its equilibrium position by using combinations of elements that possess force derivatives of such magnitudes and signs that they can satisfy the conditions required for a rotating body to be stably supported by a magnetic bearing system over a finite range of those displacements.
Post, Richard F. (Walnut Creek, CA)
A magnetic bearing system contains magnetic subsystems which act together to support a rotating element in a state of dynamic equilibrium. However, owing to the limitations imposed by Earnshaw`s Theorem, the magnetic bearing systems to be described do not possess a stable equilibrium at zero rotational speed. Therefore, mechanical stabilizers are provided, in each case, to hold the suspended system in equilibrium until its speed has exceeded a low critical speed where dynamic effects take over, permitting the achievement of a stable equilibrium for the rotating object. A state of stable equilibrium is achieved above a critical speed by use of a collection of passive elements using permanent magnets to provide their magnetomotive excitation. The magnetic forces exerted by these elements, when taken together, levitate the rotating object in equilibrium against external forces, such as the force of gravity or forces arising from accelerations. At the same time, this equilibrium is made stable against displacements of the rotating object from its equilibrium position by using combinations of elements that possess force derivatives of such magnitudes and signs that they can satisfy the conditions required for a rotating body to be stably supported by a magnetic bearing system over a finite range of those displacements. 32 figs.
Post, R.F.
Structural system identification: Structural dynamics model validation
Structural system identification is concerned with the development of systematic procedures and tools for developing predictive analytical models based on a physical structure`s dynamic response characteristics. It is a multidisciplinary process that involves the ability (1) to define high fidelity physics-based analysis models, (2) to acquire accurate test-derived information for physical specimens using diagnostic experiments, (3) to validate the numerical simulation model by reconciling differences that inevitably exist between the analysis model and the experimental data, and (4) to quantify uncertainties in the final system models and subsequent numerical simulations. The goal of this project was to develop structural system identification techniques and software suitable for both research and production applications in code and model validation.
Red-Horse, J.R.
Dynamic Reactive Power Control of Isolated Power Systems
This dissertation presents dynamic reactive power control of isolated power systems. Isolated systems include MicroGrids in islanded mode, shipboard power systems operating offshore, or any other power system operating in islanded mode intentionally...
Falahi, Milad
SUESS ET AL.: SEA FLOOR METHANE HYDRATES AT HYDRATE RIDGE, CASCADIA MARGIN Sea Floor Methane Hydrates at Hydrate Ridge, Cascadia Margin
SUESS ET AL.: SEA FLOOR METHANE HYDRATES AT HYDRATE RIDGE, CASCADIA MARGIN 1 Sea Floor Methane are exposed at the sea floor. A methane-oxidizing bacterial consortium populates the exposures of hydrate; colonies of vent macro-fauna are abundant as well. Discharge of methane from destabilized hydrate
Goldfinger, Chris
Dynamic data filtering system and method
A computer-implemented dynamic data filtering system and method for selectively choosing operating data of a monitored asset that modifies or expands a learned scope of an empirical model of normal operation of the monitored asset while simultaneously rejecting operating data of the monitored asset that is indicative of excessive degradation or impending failure of the monitored asset, and utilizing the selectively chosen data for adaptively recalibrating the empirical model to more accurately monitor asset aging changes or operating condition changes of the monitored asset.
Bickford, Randall L; Palnitkar, Rahul M
Hydrates represent gas source, drilling hazard
Gas hydrates look like ordinary ice. However, if a piece of such ice is put into warm water its behavior will be different from the ordinary melting of normal ice. In contrast, gas hydrates cause bubbles in the warm water, which indicates the high content of gas in the hydrate crystals. The presence of four components is required: gas itself, water, high pressure, and low temperature. The paper discusses how hydrates form, hydrates stability, South Caspian hydrates, and hydrates hazards for people, ships, pipelines, and drilling platforms.
Bagirov, E. [Azerbaijan Academy of Sciences, Baku (Azerbaijan); Lerche, I. [Univ. of South Carolina, Columbia, SC (United States)
Dynamics of two-dimensional dipole systems
Using a combined analytical/molecular dynamics approach, we study the current fluctuation spectra and longitudinal and transverse collective mode dispersions of the classical two-dimensional (point) dipole system (2DDS) characterized by the {phi}{sub D}(r)={mu}{sup 2}/r{sup 3} repulsive interaction potential; {mu} is the electric dipole strength. The interest in the 2DDS is twofold. First, the quasi-long-range 1/r{sup 3} interaction makes the system a unique classical many-body system, with a remarkable collective mode behavior. Second, the system may be a good model for a closely spaced semiconductor electron-hole bilayer, a system that is in the forefront of current experimental interest. The longitudinal collective excitations, which are of primary interest for the liquid phase, are acoustic at long wavelengths. At higher wave numbers and for sufficiently high coupling strength, we observe the formation of a deep minimum in the dispersion curve preceded by a sharp maximum; this is identical to what has been observed in the dispersion of the zero-temperature bosonic dipole system, which in turn emulates so-called roton-maxon excitation spectrum of the superfluid {sup 4}He. The analysis we present gives an insight into the emergence of this apparently universal structure, governed by strong correlations. We study both the liquid and the crystalline solid state. We also observe the excitation of combination frequencies, resembling the roton-roton, roton-maxon, etc. structures in {sup 4}He.
Golden, Kenneth I.; Kalman, Gabor J.; Hartmann, Peter; Donko, Zoltan [Department of Mathematics and Statistics, Department of Physics, University of Vermont, Burlington, Vermont 05401 (United States); Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467 (United States); Research Institute for Solid State Physics and Optics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest, Hungary and Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467 (United States)
Nonlinear Dynamics and Structure Formation in Complex Systems
Nonlinear Dynamics and Structure Formation in Complex Systems F. Zonca - Complex behaviors ENEA, Frascati, Italy #12;Nonlinear Dynamics and Structure Formation in Complex Systems F. Zonca-heating) of charged fusion products balances power losses #12;Nonlinear Dynamics and Structure Formation in Complex
Zonca, Fulvio
The dynamics of power system markets Fernando L. Alvarado
The dynamics of power system markets Fernando L. Alvarado Department of Electrical and Computer describing the marketplace. Dynamic market equations provide additional insights into the behavior studies the impact of various policies on the dynamic behavior of power system markets. The impact
Evaluation of the thermodynamic properties of hydrated metal oxide nanoparticles by INS techniques
In this contribution we will present a detailed methodology for the elucidation of the following aspects of the thermodynamic properties of hydrated metal oxide nanoparticles from high-resolution, low-temperature inelastic neutron scattering (INS) data: (i) the isochoric heat capacity and entropy of the hydration layers both chemi- and physisorbed to the particle surface; (ii) the magnetic contribution to the heat capacity of the nanoparticles. This will include the calculation of the vibrational density of states (VDOS) from the raw INS spectra, and the subsequent extraction of the thermodynamic data from the VDOS. This technique will be described in terms of a worked example namely, cobalt oxide (Co3O4 and CoO). To complement this evaluation of the physical properties of metal oxide nanoparticle systems, we will emphasise the importance of high-resolution, high-energy INS for the determination of the structure and dynamics of the water species, namely molecular (H2O) and dissociated water (OH, hydroxyl), confined to the oxide surfaces. For this component of the chapter we will focus on INS investigations of hydrated isostructural rutile (a-TiO2) and cassiterite (SnO2) nanoparticles. We will complete this discussion of nanoparticle analysis by including an appraisal of the INS instrumentation employed in such studies with particular focus on TOSCA [ISIS, Rutherford Appleton Laboratory (RAL), U.K.] and the newly developed spectrometer SEQUOIA [SNS, Oak Ridge National Laboratory (ORNL), U.S.A].
Spencer, Elinor [Virginia Polytechnic Institute and State University] [Virginia Polytechnic Institute and State University; Ross, Dr. Nancy [Virginia Polytechnic Institute and State University] [Virginia Polytechnic Institute and State University; Parker, Stewart F. [ISIS Facility, Rutherford Appleton Laboratory (ISIS)] [ISIS Facility, Rutherford Appleton Laboratory (ISIS); Kolesnikov, Alexander I [ORNL] [ORNL
Open Systems Dynamics for Propagating Quantum Fields
In this dissertation, I explore interactions between matter and propagating light. The electromagnetic field is modeled as a reservoir of quantum harmonic oscillators successively streaming past a quantum system. Each weak and fleeting interaction entangles the light and the system, and the light continues its course. Within the framework of open quantum systems, the light is eventually traced out, leaving the reduced quantum state of the system as the primary mathematical subject. Two major results are presented. The first is a master equation approach for a quantum system interacting with a traveling wave packet prepared with a definite number of photons. In contrast to quasi-classical states, such as coherent or thermal fields, these N-photon states possess temporal mode entanglement, and local interactions in time have nonlocal consequences. The second is a model for a three-dimensional light-matter interface for an atomic ensemble interacting with a paraxial laser beam and its application to the generation of QND spin squeezing. Both coherent and incoherent dynamics due to spatially inhomogeneous atom-light coupling across the ensemble are accounted for. Measurement of paraxially scattered light can generate squeezing of an atomic spin wave, while diffusely scattered photons lead to spatially local decoherence.
Ben Q. Baragiola
Impact of Hydrated Cement Paste Quality and Entrained Air-Void
Impact of Hydrated Cement Paste Quality and Entrained Air-Void System on the Durability of Concrete the characteristics of the entrained air-void system #12;Objectives · Review the current accepted relationship between is affected by the quality of the hydrated cement paste (HCP) and the presence of a properly entrained air
Synchronization of hypernetworks of coupled dynamical systems
We consider synchronization of coupled dynamical systems when different types of interactions are simultaneously present. We assume that a set of dynamical systems are coupled through the connections of two or more distinct networks (each of which corresponds to a distinct type of interaction), and we refer to such a system as a hypernetwork. Applications include neural networks formed of both electrical gap junctions and chemical synapses, the coordinated motion of shoals of fishes communicating through both vision and flow sensing, and hypernetworks of coupled chaotic oscillators. We first analyze the case of a hypernetwork formed of $m=2$ networks. We look for necessary and sufficient conditions for synchronization. We attempt at reducing the linear stability problem in a master stability function form, i.e., at decoupling the effects of the coupling functions from the structure of the networks. Unfortunately, we are unable to obtain a reduction in a master stability function form for the general case. However, we show that such a reduction is possible in three cases of interest: (i) the Laplacian matrices associated with the two networks commute; (ii) one of the two networks is unweighted and fully connected; (iii) one of the two networks is such that the coupling strength from node $i$ to node $j$ is a function of $j$ but not of $i$. Furthermore, we define a class of networks such that if either one of the two coupling networks belongs to this class, the reduction can be obtained independently of the other network. As an example of interest, we study synchronization of a neural hypernetwork for which the connections can be either chemical synapses or electrical gap junctions. We propose a generalization of our stability results to the case of hypernetworks formed of $m\\geq 2$ networks.
Francesco Sorrentino
Response of oceanic hydrate-bearing sediments to thermal stresses
c) aqueous, gas and hydrate phase saturations, (d) waterIntrinsic Rate of Methane Gas Hydrate Decomposition�, Chem.Western Nankai Trough�, in Gas Hydrates: Challenges for the
Moridis, G.J.; Kowalsky, M.B.
Examination of Hydrate Formation Methods: Trying to Create Representative Samples
permeability measurements of gas hydrate-bearing sediments,International Conference on Gas Hydrates, edited, p. 1058,2009), Influence of gas hydrate morphology on the seismic
Kneafsey, T.J.
Strategies for gas production from oceanic Class 3 hydrate accumulations
coexistence of aqueous, gas and hydrate phases, indicatingIntrinsic Rate of Methane Gas Hydrate Decomposition�, Chem.Makogon, Y.F. , �Gas hydrates: frozen energy,� Recherche
Moridis, George J.; Reagan, Matthew T.
Preliminary relative permeability estimates of methane hydrate-bearing sand
gas production from gas hydrate reservoirs. We estimated theof gas production from gas hydrate reservoirs. Fieldpermeability function in gas hydrate-bearing sediments is
Seol, Yongkoo; Kneafsey, Timothy J.; Tomutsa, Liviu; Moridis, George J.
Stellar and dynamical evolution within triple systems
About 5-15% of stellar systems are at least triple. About 1% of systems with a primary of $\\tgs 1 \\Mscun$ are triple with a {\\it longer} peri od that is less than 30y, and so may in principle be capable of Roche-lobe overflow in both the inner and the outer orbits, at different times. We discuss possible evolutionary paths for these systems, some of which may lead to objects that are difficult to understand in the context of purely binary evolution. An example is OW Gem, a binary containing two supergiants (spectral types F and G) with masses that difffer by a factor of 1.5. There is also a triple-star pathway which could lead rather naturally to low-mass X-ray binaries; whereas binary pathways often appear rather contrived. We also discuss some dynamical pr ocesses involved in the 3-body problem. A number of triple stars are found in clusters. Similar systems can be created by gravitational capture during N-body simulations of Galactic clusters, especially if there is a n assumed primordial binary population. We discuss the properties of these triples , and note that many can be quite long-lived.
P. P. Eggleton; L. G. Kiseleva
The current paper complements the Moridis et al. (2009) review of the status of the effort toward commercial gas production from hydrates. We aim to describe the concept of the gas hydrate petroleum system, to discuss advances, requirement and suggested practices in gas hydrate (GH) prospecting and GH deposit characterization, and to review the associated technical, economic and environmental challenges and uncertainties, including: the accurate assessment of producible fractions of the GH resource, the development of methodologies for identifying suitable production targets, the sampling of hydrate-bearing sediments and sample analysis, the analysis and interpretation of geophysical surveys of GH reservoirs, well testing methods and interpretation of the results, geomechanical and reservoir/well stability concerns, well design, operation and installation, field operations and extending production beyond sand-dominated GH reservoirs, monitoring production and geomechanical stability, laboratory investigations, fundamental knowledge of hydrate behavior, the economics of commercial gas production from hydrates, and the associated environmental concerns.
Moridis, G.J.; Collett, T.S.; Pooladi-Darvish, M.; Hancock, S.; Santamarina, C.; Boswell, R.; Kneafsey, T.; Rutqvist, J.; Kowalsky, M.; Reagan, M.T.; Sloan, E.D.; Sum, A.K.; Koh, C.
Methods and systems for combustion dynamics reduction
Methods and systems for combustion dynamics reduction are provided. A combustion chamber may include a first premixer and a second premixer. Each premixer may include at least one fuel injector, at least one air inlet duct, and at least one vane pack for at least partially mixing the air from the air inlet duct or ducts and fuel from the fuel injector or injectors. Each vane pack may include a plurality of fuel orifices through which at least a portion of the fuel and at least a portion of the air may pass. The vane pack or packs of the first premixer may be positioned at a first axial position and the vane pack or packs of the second premixer may be positioned at a second axial position axially staggered with respect to the first axial position.
Kraemer, Gilbert Otto (Greer, SC); Varatharajan, Balachandar (Cincinnati, OH); Srinivasan, Shiva (Greer, SC); Lynch, John Joseph (Wilmington, NC); Yilmaz, Ertan (Albany, NY); Kim, Kwanwoo (Greer, SC); Lacy, Benjamin (Greer, SC); Crothers, Sarah (Greenville, SC); Singh, Kapil Kumar (Rexford, NY)
On a local formalism for time evolution of dynamical systems
The formalism of local maximization for entropy gradient producing the evolution and dynamical equations for closed systems. It eliminates the inconsistency between the reversibilty of time in dynamical equations and the strict direction of irreversible evolution for complex systems, causality contradictions and ambiguity of time flow in different systems. Independently it leads to basic principles of special relativity.
Drozdov, I V
Optimal Shipboard Power System Management via Mixed Integer Dynamic Programming
Optimal Shipboard Power System Management via Mixed Integer Dynamic Programming Harry G. Kwatny' power systems using a logical specification to define the transition dynamics of the discrete subsystem following component failure(s) is a central goal of power system management including electric shipboard
Kwatny, Harry G.
Hybrid Dynamical Systems, or HDS: The Ultimate Switching Experience
Hybrid Dynamical Systems, or HDS: The Ultimate Switching Experience Michael S. Branicky Laboratory concentrated on formalizing the notion of a hybrid system as switching among an indexed collection of dynamical give a quick overview of the area of hybrid systems. I also briefly review the formal definition
Branicky, Michael S.
Thermodynamics of quantum systems under dynamical control
In this review the debated rapport between thermodynamics and quantum mechanics is addressed in the framework of the theory of periodically-driven/controlled quantum-thermodynamic machines. The basic model studied here is that of a two-level system (TLS), whose energy is periodically modulated while the system is coupled to thermal baths. When the modulation interval is short compared to the bath memory time, the system-bath correlations are affected, thereby causing cooling or heating of the TLS, depending on the interval. In steady state, a periodically-modulated TLS coupled to two distinct baths constitutes the simplest quantum heat machine (QHM) that may operate as either an engine or a refrigerator, depending on the modulation rate. We find their efficiency and power-output bounds and the conditions for attaining these bounds. An extension of this model to multilevel systems shows that the QHM power output can be boosted by the multilevel degeneracy. These results are used to scrutinize basic thermodynamic principles: (i) Externally-driven/modulated QHMs may attain the Carnot efficiency bound, but when the driving is done by a quantum device ("piston"), the efficiency strongly depends on its initial quantum state. Such dependence has been unknown thus far. (ii) The refrigeration rate effected by QHMs does not vanish as the temperature approaches absolute zero for certain quantized baths, e.g., magnons, thous challenging Nernst's unattainability principle. (iii) System-bath correlations allow more work extraction under periodic control than that expected from the Szilard-Landauer principle, provided the period is in the non-Markovian domain. Thus, dynamically-controlled QHMs may benefit from hitherto unexploited thermodynamic resources.
D. Gelbwaser-Klimovsky; Wolfgang Niedenzu; Gershon Kurizki
Dynamic Positioning System as Dynamic Energy Storage on Diesel-Electric Ships
1 Dynamic Positioning System as Dynamic Energy Storage on Diesel-Electric Ships Tor A. Johansen in order to implement energy storage in the kinetic and potential energy of the ship motion using the DP in order to relate the dynamic energy storage capacity to the maximum allowed ship position deviation
Johansen, Tor Arne
The Dynamics of Brain-Body-Environment Systems
The Dynamics of Brain-Body-Environment Systems in Behavior and Cognition An NSF IGERT Training Program Environment BodyAgent Agent Graduate Traineeships Available in Research Themes * Brain Dynamics the dynamical interaction of brains with bodies, agents with their environments, and agents with other agents
Menczer, Filippo
Estimating Power System Dynamic States Using Extended Kalman Filter
Abstract�The state estimation tools which are currently deployed in power system control rooms are based on a steady state assumption. As a result, the suite of operational tools that rely on state estimation results as inputs do not have dynamic information available and their accuracy is compromised. This paper investigates the application of Extended Kalman Filtering techniques for estimating dynamic states in the state estimation process. The new formulated �dynamic state estimation� includes true system dynamics reflected in differential equations, not like previously proposed �dynamic state estimation� which only considers the time-variant snapshots based on steady state modeling. This new dynamic state estimation using Extended Kalman Filter has been successfully tested on a multi-machine system. Sensitivity studies with respect to noise levels, sampling rates, model errors, and parameter errors are presented as well to illustrate the robust performance of the developed dynamic state estimation process.
Huang, Zhenyu; Schneider, Kevin P.; Nieplocha, Jaroslaw; Zhou, Ning
The Dynamics of Poor Systems of Galaxies
We assemble and observe a sample of poor galaxy systems that is suitable for testing N-body simulations of hierarchical clustering (Navarro, Frenk, & White 1997; NFW) and other dynamical halo models (e.g., Hernquist 1990). We (1) determine the parameters of the density profile rho(r) and the velocity dispersion profile sigma(R), (2) separate emission-line galaxies from absorption-line galaxies, examining the model parameters and as a function of spectroscopic type, and (3) for the best-behaved subsample, constrain the velocity anisotropy parameter, beta, which determines the shapes of the galaxy orbits. The NFW universal profile and the Hernquist (1990) model both provide good descriptions of the spatial data. In most cases an isothermal sphere is ruled out. Systems with declining sigma(R) are well-matched by theoretical profiles in which the star-forming galaxies have predominantly radial orbits (beta > 0); many of these galaxies are probably falling in for the first time. There is significant evidence for spatial segregation of the spectroscopic classes regardless of sigma(R).
A. Mahdavi; M. J. Geller; H. Boehringer; M. J. Kurtz; M. Ramella
About Gas Hydrates? What Role Do Gas Hydrates Play in Nature? Theme 2 Gas Hydrates as a Potential Energy Resource Are Gas Hydrates a Potential Energy Source? How Big Is the...
Using Carbon Dioxide to Enhance Recovery of Methane from Gas Hydrate Reservoirs: Final Summary Report
Carbon dioxide sequestration coupled with hydrocarbon resource recovery is often economically attractive. Use of CO2 for enhanced recovery of oil, conventional natural gas, and coal-bed methane are in various stages of common practice. In this report, we discuss a new technique utilizing CO2 for enhanced recovery of an unconventional but potentially very important source of natural gas, gas hydrate. We have focused our attention on the Alaska North Slope where approximately 640 Tcf of natural gas reserves in the form of gas hydrate have been identified. Alaska is also unique in that potential future CO2 sources are nearby, and petroleum infrastructure exists or is being planned that could bring the produced gas to market or for use locally. The EGHR (Enhanced Gas Hydrate Recovery) concept takes advantage of the physical and thermodynamic properties of mixtures in the H2O-CO2 system combined with controlled multiphase flow, heat, and mass transport processes in hydrate-bearing porous media. A chemical-free method is used to deliver a LCO2-Lw microemulsion into the gas hydrate bearing porous medium. The microemulsion is injected at a temperature higher than the stability point of methane hydrate, which upon contacting the methane hydrate decomposes its crystalline lattice and releases the enclathrated gas. Small scale column experiments show injection of the emulsion into a CH4 hydrate rich sand results in the release of CH4 gas and the formation of CO2 hydrate
McGrail, B. Peter; Schaef, Herbert T.; White, Mark D.; Zhu, Tao; Kulkarni, Abhijeet S.; Hunter, Robert B.; Patil, Shirish L.; Owen, Antionette T.; Martin, P F.
Electrical Resistivity Investigation of Gas Hydrate Distribution in Mississippi Canyon Block 118, Gulf of Mexico
Electrical methods offer a geophysical approach for determining the sub-bottom distribution of hydrate in deep marine environments. Methane hydrate is essentially non-conductive. Hence, sediments containing hydrate are more resistive than sediments without hydrates. To date, the controlled source electromagnetic (CSEM) method has been used in marine hydrates studies. This project evaluated an alternative electrical method, direct current resistivity (DCR), for detecting marine hydrates. DCR involves the injection of direct current between two source electrodes and the simultaneous measurement of the electric potential (voltage) between multiple receiver electrodes. The DCR method provides subsurface information comparable to that produced by the CSEM method, but with less sophisticated instrumentation. Because the receivers are simple electrodes, large numbers can be deployed to achieve higher spatial resolution. In this project a prototype seafloor DCR system was developed and used to conduct a reconnaissance survey at a site of known hydrate occurrence in Mississippi Canyon Block 118. The resulting images of sub-bottom resistivities indicate that high-concentration hydrates at the site occur only in the upper 50 m, where deep-seated faults intersect the seafloor. Overall, there was evidence for much less hydrate at the site than previously thought based on available seismic and CSEM data alone.
Dunbar, John
Effect of Elevated Curing Temperature on Early Hydration and Microstructure of Composite Cements
Effect of Elevated Curing Temperature on Early Hydration and Microstructure of Composite Cements J, Seascale, Cumbria, CA20 1PG, UK Abstract The heat of hydration of a number of composite cement systems has of composite cements based on the partial replacement of Portland cement by waste materials has become
U N C L A S S I F I E D Gas Hydrate Experimental Capabilities at the Los Alamos
investigating synthesized (both in-situ and ex-situ) gas hydrates (methane, ethane, propane, CO2 and H2) using-host interactions that drive structure and dynamics. Lee et al., Science 2005 ·Storage of hydrogen in molecular form. ·Tetrahydrofuran (THF)-containing gas hydrate has been proposed as a storage material. THF + D2 clathrates
Downs, Robert T.
Analysis of Power System Dynamics Subject to Stochastic Power Injections
to the computation of long-term power system state statistics; and to short-term probabilistic dynamic performance/reliability of renewable re- sources such as wind energy conversion systems (WECS) and photovoltaic energy conversion
DeVille, Lee
Applications of axial and radial compressor dynamic system modeling
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. ...
Spakovszky, Zolt�n S. (Zolt�n S�ndor), 1972-
15.872 System Dynamics II, Fall 2010
15.872 is a continuation of 15.871 Introduction to System Dynamics. It emphasizes tools and methods needed to apply systems thinking and simulation modeling successfully in complex real-world settings. The course uses ...
Sterman, John
STABILITY ANALYSIS OF INTERCONNECTED POWER SYSTEMS COUPLED WITH MARKET DYNAMICS F.L. Alvarado1 J of generators and network interconnections. This paper examines questions of stability in such coupled systems
Estimation Strategies for Constrained and Hybrid Dynamical Systems
The estimation approaches examined in this dissertation focus on manipulating system dynamical models to allow the well-known form of the continuous-discrete extended Kalman filter (CDEKF) to accommodate constrained and hybrid systems...
Parish, Julie Marie Jones
Can xenon in water inhibit ice growth? Molecular dynamics of phase transitions in water$-$Xe system
Motivated by recent experiments showing the promise of noble gases as cryoprotectants, we perform molecular dynamics modeling of phase transitions in water with xenon under cooling. We study the structure and dynamics of xenon water solution as a function of temperature. Homogeneous nucleation of clathrate hydrate phase is observed and characterized. As the temperature is further reduced we observe hints of dissociation of clathrate due to stronger hydrophobic hydration, pointing towards a possible instability of clathrate at cryogenic temperatures and conversion to an amorphous phase comprised of "xenon + hydration shell" Xe$\\cdot$(H$_{2}$O)$_{21.5}$ clusters. Simulations of ice$-$xenon solution interface in equilibrium and during ice growth reveal the effects of xenon on the ice$-$liquid interface, where adsorbed xenon causes roughening of ice surface but does not preferentially form clathrate. These results provide evidence against the ice-blocker mechanism of xenon cryoprotection.
Vasilii I. Artyukhov; Alexander Yu. Pulver; Alex Peregudov; Igor Artyuhov
Hybrid Renewable Energy Systems for a Dynamically Positioned Buoy
i Hybrid Renewable Energy Systems for a Dynamically Positioned Buoy by Robert Sean Pagliari ________________________ #12; ii We the undersigned committee hereby approve the attached thesis Hybrid Renewable Energy, College of Engineering #12; iii Abstract Hybrid Renewable Energy Systems for a Dynamically Positioned
Wood, Stephen L.
Robustness of chimera states in complex dynamical systems
Robustness of chimera states in complex dynamical systems Nan Yao1,2 , Zi-Gang Huang2,3 , Ying State University, Tempe, Arizona 85287, USA. The remarkable phenomenon of chimera state in systems distinct types of dynamical behaviors, in spite of identity of the oscillators. But how robust are chimera
Lai, Ying-Cheng
Dynamic wind turbine models in power system simulation tool
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
Input Design for Nonlinear Stochastic Dynamic Systems -A Particle Filter
Input Design for Nonlinear Stochastic Dynamic Systems - A Particle Filter Approach R. Bhushan in nonlinear stochastic dynamic systems. The approach relies on minimizing a function of the covariance]). There has also been work done on obtaining finite sam- ple covariance estimates (Weyer et al. [1999], Weyer
Sch�n, Thomas
Controlling Complex Systems and Developing Dynamic Technology
the power output of steam engines to feed the factories ofas a whole, the governed steam engine becomes a less dynamic
Avizienis, Audrius Victor
Generic solar photovoltaic system dynamic simulation model specification.
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.
Ellis, Abraham; Behnke, Michael Robert; Elliott, Ryan Thomas
High-pressure gas hydrates�
It has long been known that crystalline hydrates are formed by many simple gases that do not interact strongly with water, and in most cases the gas molecules or atoms occupy 'cages' formed by a framework of water molecules. The majority...
Loveday, J. S.; Nelmes, R. J.
New techniques for monitoring cement hydration under simulated well conditions
Fourier transform infrared spectroscopy and synchrotron X-ray powder diffraction methods are described for studying cement hydration chemistry at temperatures up to 200 C, covering the normal temperature range of wellbore cementing. The methods provide complementary information on the transformation of silicate, ferrite and sulfate minerals. The thermal decomposition of the cement mineral ettringite is shown to occur at 114 C in a sealed system in contact with water. The FTIR spectrum of a well cement slurry hydrating at 150 C and 2,000 psi is analyzed. The anomalous thickening time behavior of certain cements around 75--100 C is discussed in the light of new data on the hydration of a Class G cement at 65 and 95 C, with and without retarder.
Luke, K.; Hall, C.; Jones, T. [Schlumberger Cambridge Research (United Kingdom); Barnes, P.; Turillas, X.; Lewis, A. [Univ. of London (United Kingdom). Birkbeck College
Protein structure and hydration probed by SANS and osmotic stress
Interactions governing protein folding, stability, recognition, and activity are mediated by hydration. Here, we use small-angle neutron scattering coupled with osmotic stress to investigate the hydration of two proteins, lysozyme and guanylate kinase (GK), in the presence of solutes. By taking advantage of the neutron contrast variation that occurs upon addition of these solutes, the number of protein-associated (solute-excluded) water molecules can be estimated from changes in both the zero-angle scattering intensity and the radius of gyration. Poly(ethylene glycol) exclusion varies with molecular weight. This sensitivity can be exploited to probe structural features such as the large internal GK cavity. For GK, small-angle neutron scattering is complemented by isothermal titration calorimetry with osmoticstress to also measure hydration changes accompanying ligand binding. These results provide a framework for studying other biomolecular systems and assemblies using neutron scattering together with osmotic stress.
Rau, Dr. Donald [National Institutes of Health
Toward Standards for Dynamics in Electric Energy Systems
Toward Standards for Dynamics in Electric Energy Systems Future Grid Initiative White Paper Power Systems Engineering Research Center Empowering Minds to Engineer the Future Electric Energy System #12 Engineering Research Center The Power Systems Engineering Research Center (PSERC) is a multi-university Center
Gas hydrate reservoir characteristics and economics
The primary objective of the DOE-funded USGS Gas Hydrate Program is to assess the production characteristics and economic potential of gas hydrates in northern Alaska. The objectives of this project for FY-1992 will include the following: (1) Utilize industry seismic data to assess the distribution of gas hydrates within the nearshore Alaskan continental shelf between Harrison Bay and Prudhoe Bay; (2) Further characterize and quantify the well-log characteristics of gas hydrates; and (3) Establish gas monitoring stations over the Eileen fault zone in northern Alaska, which will be used to measure gas flux from destabilized hydrates.
Collett, T.S.; Bird, K.J.; Burruss, R.C.; Lee, Myung W.
Paleooceanographic evidence has been used to postulate that methane from oceanic hydrates may have had a significant role in regulating climate. However, the behavior of contemporary oceanic methane hydrate deposits subjected to rapid temperature changes, like those now occurring in the arctic and those predicted under future climate change scenarios, has only recently been investigated. Field investigations have discovered substantial methane gas plumes exiting the seafloor along the Arctic Ocean margin, and the plumes appear at depths corresponding to the upper limit of a receding gas hydrate stability zone. It has been suggested that these plumes may be the first visible signs of the dissociation of shallow hydrate deposits due to ongoing climate change in the arctic. We simulate the release of methane from oceanic deposits, including the effects of fully-coupled heat transfer, fluid flow, hydrate dissociation, and other thermodynamic processes, for systems representative of segments of the Arctic Ocean margins. The modeling encompasses a range of shallow hydrate deposits from the landward limit of the hydrate stability zone down to water depths beyond the expected range of century-scale temperature changes. We impose temperature changes corresponding to predicted rates of climate change-related ocean warming and examine the possibility of hydrate dissociation and the release of methane. The assessment is performed at local-, regional-, and basin-scales. The simulation results are consistent with the hypothesis that dissociating shallow hydrates alone can result in significant methane fluxes at the seafloor. However, the methane release is likely to be confined to a narrow region of high dissociation susceptibility, defined by depth and temperature, and that any release will be continuous and controlled, rather than explosive. This modeling also establishes the first realistic bounds for methane release along the arctic continental shelf for potential hydrate dissociation scenarios, and ongoing work may help confirm whether climate change is already impacting the stability of the vast oceanic hydrate reservoir.
Reagan, M.; Moridis, G.; Elliott, S.; Maltrud, M.; Cameron-Smith, P.
Handbook of gas hydrate properties and occurrence
This handbook provides data on the resource potential of naturally occurring hydrates, the properties that are needed to evaluate their recovery, and their production potential. The first two chapters give data on the naturally occurring hydrate potential by reviewing published resource estimates and the known and inferred occurrences. The third and fourth chapters review the physical and thermodynamic properties of hydrates, respectively. The thermodynamic properties of hydrates that are discussed include dissociation energies and a simplified method to calculate them; phase diagrams for simple and multi-component gases; the thermal conductivity; and the kinetics of hydrate dissociation. The final chapter evaluates the net energy balance of recovering hydrates and shows that a substantial positive energy balance can theoretically be achieved. The Appendices of the Handbook summarize physical and thermodynamic properties of gases, liquids and solids that can be used in designing and evaluating recovery processes of hydrates. 158 references, 67 figures, 47 tables.
Kuustraa, V.A.; Hammershaimb, E.C.
System Transition: Dynamics of Change in the US Air TransportationSystem
System Transition: Dynamics of Change in the US Air TransportationSystem by Aleksandra L Education Committee #12;#12;System Transition: Dynamics of Change in the US Air Transportation System of the requirements for the degree of Doctor of Philosophy in Technology, Management, and Policy Abstract The US Air
de Weck, Olivier L.
Enhancement of Hydrogen Storage Capacity in Hydrate Lattices
First principles electronic structure calculations of the gas phase pentagonal dodecahedron (H2O)20 (D-cage) and tetrakaidecahedron (H2O)24 (T-cage), which are building blocks of structure I (sI) hydrate lattice, suggest that these can accommodate up to a maximum of 5 and 7 guest hydrogen molecules, respectively. For the pure hydrogen hydrate, Born-Oppenheimer Molecular Dynamics (BOMD) simulations of periodic (sI) hydrate lattices indicate that the guest molecules are released into the vapor phase via the hexagonal phases of the larger T-cages. An additional mechanism for the migration between neighboring D- and T-cages was found to occur through a shared pentagonal face via the breaking and reforming of a hydrogen bond. This molecular mechanism is also found for the expulsion of a CH4 molecule from the D-cage. The presence of methane in the larger T-cages was found to block this release, therefore suggesting possible scenarios for the stabilization of these mixed guest clathrate hydrates and the potential enhancement of their hydrogen storage capacity.
Yoo, Soohaeng; Xantheas, Sotiris S.
A Study of Formation and Dissociation of Gas Hydrate
and initial pressure. The aim of the second part of the study was the evaluation of the formation of gas hydrate and ice phases in a super-cooled methane-water system under the cooling rates of 0.45 and 0.6 degrees C/min, and the initial pressures of 1500...
Badakhshan Raz, Sadegh
The discovery of multi-planet extrasolar systems has kindled interest in using their orbital evolution as a probe of planet formation. Accurate descriptions of planetary orbits identify systems that could hide additional planets or be in a special dynamical state, and inform targeted follow-up observations. We combine published radial velocity data with Markov Chain Monte Carlo analyses in order to obtain an ensemble of masses, semimajor axes, eccentricities, and orbital angles for each of the five dynamically active multi-planet systems: HD 11964, HD 38529, HD 108874, HD 168443, and HD 190360. We dynamically evolve these systems using 52,000 long-term N-body integrations that sample the full range of possible line-of-sight and relative inclinations, and we report on the system stability, secular evolution, and the extent of the resonant interactions. We find that planetary orbits in hierarchical systems exhibit complex dynamics and can become highly eccentric and maybe significantly inclined. Additionally, we incorporate the effects of general relativity in the long-term simulations and demonstrate that it can qualitatively affect the dynamics of some systems with high relative inclinations. The simulations quantify the likelihood of different dynamical regimes for each system and highlight the dangers of restricting simulation phase space to a single set of initial conditions or coplanar orbits.
Veras, Dimitri; Ford, Eric B., E-mail: email@example.com [Astronomy Department, University of Florida, 211 Bryant Space Sciences Center, Gainesville, FL 32111 (United States)
Fractal and Chaotic Dynamics in Nervous Systems Chris C. King
Fractal and Chaotic Dynamics in Nervous Systems Chris C. King Department of Mathematics & Statistics, University of Auckland. Abstract : This paper presents a review of fractal and chaotic dynamics distributed processing models and their relation to chaos and overviews reasons why chaotic and fractal
King, Chris
Laboratory measurements on core-scale sediment/hydrate samples to predice reservoir behavior
International Conference on Gas Hydrates, Trondheim, Norway,coring of near-surface gas hydrate sediments on HydrateInternational Conference on Gas Hydrates, Trondheim, Norway,
Kneafsey, Timothy J.; Seol, Yongkoo; Moridis, George J.; Tomutsa, Liviu; Freifeld, Barry M.
Amplitude death in coupled slow and fast dynamical systems
We study how mismatch between dynamical time scales of interacting identical systems can result in the suppression of collective dynamics leading to amplitude death. We find that the inability of the interacting systems to fall in step leads to difference in phase as well as change in amplitude. If the mismatch is small, the systems settle to a frequency synchronised state with constant phase difference. But as mismatch in time scale increases, the systems have to compromise to a state of no oscillations. We establish that this regime of amplitude death exists in a net work of identical systems also for sufficient number of slow systems. For standard nonlinear systems, the regions of quenched dynamics in the parameter plane and the transition curves are studied analytically and confirmed by numerical simulations.
Kajari Gupta; G. Ambika
Brain Prostheses as a Dynamic System (Immortalizing the Human Brain?)
Interest in development of brain prostheses, which might be proposed to recover mental functions lost due to neuron-degenerative disease or trauma, requires new methods in molecular engineering and nanotechnology to build artificial brain tissues. We develop a Dynamic Core model to analyze complexity of damaged biological neural network as well as transition and recovery of the system functionality due to changes in the system environment. We provide a method to model complexity of physical systems which might be proposed as an artificial tissue or prosthesis. Delocalization of Dynamic Core model is developed to analyze migration of mental functions in dynamic bio-systems which undergo architecture transition induced by trauma. Term Dynamic Core is used to define a set of causally related functions and Delocalization is used to describe the process of migration. Information geometry and topological formalisms are proposed to analyze information processes. A holographic model is proposed to construct dynamic environment with self-poetic Dynamic Core which preserve functional properties under transition from one host to another. We found statistical constraints for complex systems which conserve a Dynamic Core under environment transition. Also we suggest those constraints might provide recommendations for nanotechnologies and tissue engineering used in development of an artificial brain tissue.
Vadim Astakhov; Tamara Astakhova
Dynamical Systems and Embedded Cognition Randall D. Beer
1 Dynamical Systems and Embedded Cognition Randall D. Beer Cognitive Science Program Dept University Press. Please address all correspondence to: Randall D. Beer Phone: (812) 856-0873 Cognitive
Beer, Randall D.
Regular Symbolic Analysis of Dynamic Networks of Pushdown Systems
Regular Symbolic Analysis of Dynamic Networks of Pushdown Systems Ahmed Bouajjani1, Markus M¨uller-Olm Bouajjani, Markus M¨uller-Olm, and Tayssir Touili parallel calls. In a multithreaded program such a command
Müller-Olm, Markus
Regular Symbolic Analysis of Dynamic Networks of Pushdown Systems Ahmed Bouajjani 1 , Markus M�?ullerOlm #12; 474 Ahmed Bouajjani, Markus M�?ullerOlm, and Tayssir Touili parallel calls. In a multithreaded
Regular Symbolic Analysis of Dynamic Networks of Pushdown Systems Ahmed Bouajjani 1 , Markus M�?ullerOlm Bouajjani, Markus M�?ullerOlm, and Tayssir Touili parallel calls. In a multithreaded program such a command
Touili, Tayssir
Regular Symbolic Analysis of Dynamic Networks of Pushdown Systems Ahmed Bouajjani1, Markus M¨uller-Olm #12;474 Ahmed Bouajjani, Markus M¨uller-Olm, and Tayssir Touili parallel calls. In a multithreaded
and dynamically loaded to run on the FPGA. 1. INTRODUCTION A Configurable System-on-a-Chip (CSoC) has one or more microprocessors integrated with a field programmable gate array (FPGA). These CSoC devices' high transistor
Najjar, Walid A.
Frequency-based structural damage identification and dynamic system characterisation�
This thesis studies structural dynamic system identification in a frequency-based framework. The basic consideration stems from the fact that frequencies may generally be measured with higher accuracy than other pertinent ...
Mao, Lei
Approximate dynamic programming with applications in multi-agent systems
This thesis presents the development and implementation of approximate dynamic programming methods used to manage multi-agent systems. The purpose of this thesis is to develop an architectural framework and theoretical ...
Valenti, Mario J. (Mario James), 1976-
Dynamically Quantifying and Improving the Reliability of Distributed Storage Systems
Dynamically Quantifying and Improving the Reliability of Distributed Storage Systems Rekha Bachwani-scale storage systems can be significantly improved by using bet- ter reliability metrics and more efficient on a distributed storage system based on erasure codes. We find that MinI improves relia- bility significantly
Bianchini, Ricardo
Dynamic System Performance of SISO, MISO and MIMO Alamouti Schemes
Dynamic System Performance of SISO, MISO and MIMO Alamouti Schemes Dorra Ben Cheikh Battikh , Jean, coupecho, email@example.com Abstract--In this paper, the performance of a SISO system, a 2 � 1 MISO multiplexing tradeoff for a 2 � 1 MISO system. Many other techniques have been proposed to exploit antennas
Paris-Sud XI, Universit� de
Responsive Systems Comparison Method: Dynamic Insights into Designing a Satellite
System (SRS) Critical issue in national security space Unique all-weather surveillance capability) National Security Strategy/Policy National Security Strategy/Policy Resources (fungible assetsResponsive Systems Comparison Method: Dynamic Insights into Designing a Satellite Radar System Adam
Interpolating dynamical systems: Applications to experimental data analysis
Experimental data from Rayleigh-Benard convection is used to demonstrate new techniques in data analysis. The data, in the form of Poincare sections, are fit to a map of the plane as a function of a system control parameter. This provides a very useful method for interpolating experimental low-dimensional dynamical systems. The fitted map can then be studied using numerical bifurcation methods or other nonlinear dynamics analysis techniques. 16 refs., 3 figs., 1 tab.
Ecke, R.E.
The 1st Joint International Conference on Multibody System Dynamics May 2527, 2010, Lappeenranta, Finland
The 1st Joint International Conference on Multibody System Dynamics May 2527, 2010, Lappeenrantast Joint International Conference on Multibody System Dynamics (IMSD'10)., Lappeenranta : Finland
Structure H hydrate phase equilibria of paraffins, naphthalenes, and olefins with methane
Initial phase equilibrium data are reported for 10 methane + liquid hydrocarbon systems forming structure H hydrates in the pressure range of 1--6 MPa. Four-phase equilibrium conditions were measured for each system, with paraffinic, naphthenic, and olefinic liquid hydrocarbons filling the large cage of structure H, and methane stabilizing the two smaller cages present in the hydrate. Many of these liquid hydrocarbons constitute a small fraction of crude oils and condensates, and the high stability and relative ease of formation of structure H suggest a possible impact of these hydrates upon hydrocarbon facilities.
Mehta, A.P.; Sloan, E.D. Jr. (Colorado School of Mines, Golden, CO (United States))
Ion Hydration and Associated Defects in Hydrogen Bond Network of Water: Observation of Reorientationally Slow Water Molecules Beyond First Hydration Shell in Aqueous Solutions of MgCl$_2$
Effects of presence of ions, at moderate to high concentrations, on dynamical properties of water molecules are investigated through classical molecular dynamics simulations using two well known non-polarizable water models. Simulations reveal that the presence of magnesium chloride (MgCl$_2$) induces perturbations in the hydrogen bond network of water leading to the formation of bulk-like domains with \\textquoteleft defect sites\\textquoteright~on boundaries of such domains: water molecules at such defect sites have less number of hydrogen bonds than those in bulk water. Reorientational autocorrelation functions for dipole vectors of such defect water molecules are computed at different concentrations of ions and compared with system of pure water. Earlier experimental and simulation studies indicate significant differences in reorientational dynamics for water molecules in the first hydration shell of many dissolved ions. Results of this study suggest that defect water molecules, which are beyond the first hydration shells of ions, also experience significant slowing down of reorientation times as a function of concentration in the case of MgCl$_2$. However, addition of cesium chloride(CsCl) to water does not perturb the hydrogen bond network of water significantly even at higher concentrations. This difference in behavior between MgCl$_2$ and CsCl is consistent with the well-known Hofmeister series.
Upayan Baul; Satyavani Vemparala
Polymer electrolyte membranes from fluorinated polyisoprene-block-sulfonated polystyrene: Structural evolution with hydration and heating
Small-angle neutron scattering (SANS) and ultra-small-angle X-ray scattering (USAXS) have been used to study the structural changes in fluorinated polyisoprene/sulfonated polystyrene (FISS) diblock copolymers as they evolved from the dry state to the water swollen state. A dilation of the nanometer-scale hydrophilic domains has been observed as hydration increased, with greater dilation occurring in the more highly sulfonated samples or upon hydration at higher temperatures. Furthermore, a decrease in the order in these phase separated structures is observed upon swelling. The glass transition temperatures of the fluorinated blocks have been observed to decrease upon hydration of these materials, and at the highest hydration levels, differential scanning calorimetry (DSC) has shown the presence of tightly bound water. A precipitous drop in the mechanical integrity of the 50% sulfonated materials is also observed upon exceeding the glass transition temperature (Tg), as measured by dynamic mechanical analysis (DMA).
Sodeye, Akinbode [Department of Polymer Science and Engineering, University of Massachusetts; Huang, Tianzi [University of Tennessee, Knoxville (UTK); Gido, Samuel [University of Massachusetts, Amherst; Mays, Jimmy [ORNL
System-environment correlations and Non-Markovian dynamics
We determine the total state dynamics of a dephasing open quantum system using the standard environment of harmonic oscillators. Of particular interest are random unitary approaches to the same reduced dynamics and system-environment correlations in the full model. Concentrating on a model with an at times negative dephasing rate, the issue of "non-Markovianity" will also be addressed. Crucially, given the quantum environment, the appearance of non-Markovian dynamics turns out to be accompanied by a loss of system-environment correlations. Depending on the initial purity of the qubit state, these system-environment correlations may be purely classical over the whole relevant time scale, or there may be intervals of genuine system-environment entanglement. In the latter case, we see no obvious relation between the build-up or decay of these quantum correlations and "Non-Markovianity".
Ansgar Pernice; Julius Helm; Walter T. Strunz
In the late spring of 2008, the Chevron-led Gulf of Mexico Gas Hydrate Joint Industry Project (JIP) expects to conduct an exploratory drilling and logging campaign to better understand gas hydrate-bearing sands in the deepwater Gulf of Mexico. The JIP Site Selection team selected three areas to test alternative geological models and geophysical interpretations supporting the existence of potential high gas hydrate saturations in reservoir-quality sands. The three sites are near existing drill holes which provide geological and geophysical constraints in Alaminos Canyon (AC) lease block 818, Green Canyon (GC) 955, and Walker Ridge (WR) 313. At the AC818 site, gas hydrate is interpreted to occur within the Oligocene Frio volcaniclastic sand at the crest of a fold that is shallow enough to be in the hydrate stability zone. Drilling at GC955 will sample a faulted, buried Pleistocene channel-levee system in an area characterized by seafloor fluid expulsion features, structural closure associated with uplifted salt, and abundant seismic evidence for upward migration of fluids and gas into the sand-rich parts of the sedimentary section. Drilling at WR313 targets ponded sheet sands and associated channel/levee deposits within a minibasin, making this a non-structural play. The potential for gas hydrate occurrence at WR313 is supported by shingled phase reversals consistent with the transition from gas-charged sand to overlying gas-hydrate saturated sand. Drilling locations have been selected at each site to 1) test geological methods and models used to infer the occurrence of gas hydrate in sand reservoirs in different settings in the northern Gulf of Mexico; 2) calibrate geophysical models used to detect gas hydrate sands, map reservoir thicknesses, and estimate the degree of gas hydrate saturation; and 3) delineate potential locations for subsequent JIP drilling and coring operations that will collect samples for comprehensive physical property, geochemical and other analyses.
Hutchinson, D.R. (USGS); Shelander, D. (Schlumberger, Houston, TX); Dai, J. (Schlumberger, Hoston, TX); McConnell, D. (AOA Geophysics, Inc., Houston, TX); Shedd, W. (Minerals Management Service); Frye, M. (Minerals Management Service); Ruppel, C. (USGS); Boswell, R.; Jones, E. (Chevron Energy Technology Corp., Houston, TX); Collett, T.S. (USGS); Rose, K.; Dugan, B. (Rice Univ., Houston, TX); Wood, W. (U.S. Naval Research Laboratory); Latham, T. (Chevron Energy Technology Corp., Houston, TX)
Hydrate-phobic surfaces: fundamental studies in clathrate hydrate adhesion reduction
Clathrate hydrate formation and subsequent plugging of deep-sea oil and gas pipelines represent a significant bottleneck for deep-sea oil and gas operations. Current methods for hydrate mitigation are expensive and energy ...
Smith, J. David
Development of Alaskan gas hydrate resources
The research undertaken in this project pertains to study of various techniques for production of natural gas from Alaskan gas hydrates such as, depressurization, injection of hot water, steam, brine, methanol and ethylene glycol solutions through experimental investigation of decomposition characteristics of hydrate cores. An experimental study has been conducted to measure the effective gas permeability changes as hydrates form in the sandpack and the results have been used to determine the reduction in the effective gas permeability of the sandpack as a function of hydrate saturation. A user friendly, interactive, menu-driven, numerical difference simulator has been developed to model the dissociation of natural gas hydrates in porous media with variable thermal properties. A numerical, finite element simulator has been developed to model the dissociation of hydrates during hot water injection process.
Kamath, V.A.; Sharma, G.D.; Patil, S.L.
Physical Properties of Gas Hydrates: A Review
Methane gas hydrates in sediments have been studied by several investigators as a possible future energy resource. Recent hydrate reserves have been estimated at approximately 1016?m3 of methane gas worldwide at standard temperature and pressure conditions. In situ dissociation of natural gas hydrate is necessary in order to commercially exploit the resource from the natural-gas-hydrate-bearing sediment. The presence of gas hydrates in sediments dramatically alters some of the normal physical properties of the sediment. These changes can be detected by field measurements and by down-hole logs. An understanding of the physical properties of hydrate-bearing sediments is necessary for interpretation of geophysical data collected in field settings, borehole, and slope stability analyses; reservoir simulation; and production models. This work reviews information available in literature related to the physical properties of sediments containing gas hydrates. A brief review of the physical properties of bulk gas hydrates is included. Detection methods, morphology, and relevant physical properties of gas-hydrate-bearing sediments are also discussed.
Gabitto, Jorge [Prairie View A& M University; Tsouris, Costas [ORNL
to thank my advisor Professor Steven Constable for creatingDiego, 2008 Professor Steven Constable, Chair Gas hydrate isProfessor Professor Steven Constable, Chair Kevin Brown Je?
Imaging Hydrated Microbial Extracellular Polymers: Comparative...
dehydration-based sample preparation that resulted in the collapse of hydrated gel-like EPS into filamentous structures. Dehydration-induced polymer collapse can lead to...
The Structure and Transport of Water and Hydrated Ions Within Hydrophobic, Nanoscale Channels
The purpose of this project includes an experimental and modeling investigation into water and hydrated ion structure and transport at nanomaterials interfaces. This is a topic relevant to understanding the function of many biological systems such as aquaporins that efficiently shuttle water and ion channels that permit selective transport of specific ions across cell membranes. Carbon nanotubes (CNT) are model nanoscale, hydrophobic channels that can be functionalized, making them artificial analogs for these biological channels. This project investigates the microscopic properties of water such as water density distributions and dynamics within CNTs using Nuclear Magnetic Resonance (NMR) and the structure of hydrated ions at CNT interfaces via X-ray Absorption Spectroscopy (XAS). Another component of this work is molecular simulation, which can predict experimental measurables such as the proton relaxation times, chemical shifts, and can compute the electronic structure of CNTs. Some of the fundamental questions this work is addressing are: (1) what is the length scale below which nanoscale effects such as molecular ordering become important, (2) is there a relationship between molecular ordering and transport?, and (3) how do ions interact with CNT interfaces? These are questions of interest to the scientific community, but they also impact the future generation of sensors, filters, and other devices that operate on the nanometer length scale. To enable some of the proposed applications of CNTs as ion filtration media and electrolytic supercapacitors, a detailed knowledge of water and ion structure at CNT interfaces is critical.
Holt, J K; Herberg, J L; Wu, Y; Schwegler, E; Mehta, A
Visual exploration of 2D autonomous dynamical systems
In an introductory course on dynamical systems or Hamiltonian mechanics, vector field diagrams are a central tool to show a system's qualitative behaviour in a certain domain. Because of their low sampling rates and the involved issues of vector normalization, these plots give only a coarse insight and are unable to convey the vector field behaviour at locations with high variation, in particular in the neighborhood of critical points. Similarly, automatic generation of phase portraits based on traditional sampling cannot precisely capture separatrices or limit cylces. In this paper, we present ASysViewer, an application for the interactive visual exploration of two-dimensional autonomous dynamical systems using line integral convolution techniques for visualization, and grid-based techniques to extract critical points and separatrices. ASysViewer is addressed to undergraduate students during their first course in dynamical systems or Hamiltonian mechanics.
M�ller, Thomas
SYSTEM DYNAMICS USE FOR TECHNOLOGIES ASSESSMENT Egils Ginters (a)
, and existence of concurrent technologies for sustainability assessment. Keywords: technology assessment, system and sustainability of the new technology in real time. In the framework of FP7-ICT- 2009-5 CHOREOS project No. 257178SYSTEM DYNAMICS USE FOR TECHNOLOGIES ASSESSMENT Egils Ginters (a) , Zane Barkane (b) , Hugues
Dynamics of connected vehicle systems with delayed acceleration feedback
predecessor is measured by radar and the vehicle is actuated accordingly. Since the delay in these systems conclusions are verified by simulations at the nonlinear level. �? 2014 Elsevier Ltd. All rights reserved. 1 limited ability to change the dynamics at the system level, which is necessary if one wishes to eliminate
Daly, Samantha
Cognitive Modeling Carsten Pfeffer Dynamical Systems Approaches to
Cognitive Modeling Carsten Pfeffer Dynamical Systems Approaches to Cognition Carsten Pfeffer Universität Bremen December 1st, 2014 December 1st, 2014 1/30 #12;Cognitive Modeling Carsten Pfeffer Introduction Physical Symbol Systems December 1st, 2014 2/30 #12;Cognitive Modeling Carsten Pfeffer
Bremen, Universität
September 23, 1997 Rare Events in Stochastic Dynamical Systems and
September 23, 1997 Rare Events in Stochastic Dynamical Systems and Failures in UltraReliable reliable is the system, the sharper is the approximation. In this model, we consider two types of failures that the distribution of a failure time can be approximated by an exponen tial law is not new in software reliability
Learning Nonlinear Dynamical Systems using an EM Algorithm
Learning Nonlinear Dynamical Systems using an EM Algorithm Zoubin Ghahramani and Sam T. Roweis identi cation in linear stochastic state-space models, where the state variables are hidden from become tractable and the maximization step can be solved via systems of linear equations. 1 Stochastic
Ghahramani, Zoubin
Inventory management with dynamic Bayesian network software systems
Inventory management with dynamic Bayesian network software systems Mark Taylor1 and Charles Fox2 email@example.com Abstract. Inventory management at a single or multiple levels of a supply chain is usually performed-the-shelf graphical software systems. We show how such sys- tems may be deployed to model a simple inventory problem
Barker, Jon
Orbits of hybrid systems as qualitative indicators of quantum dynamics
Hamiltonian theory of hybrid quantum-classical systems is used to study dynamics of the classical subsystem coupled to different types of quantum systems. It is shown that the qualitative properties of orbits of the classical subsystem clearly indicate if the quantum subsystem does or does not have additional conserved observables.
N. Buric; D. B. Popovic; M. Radonjic; S. Prvanovic
The Great Gas Hydrate Escape
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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassiveSubmittedStatus TomAboutManusScience andFebruaryTheFarrel W.Great Gas Hydrate
Microstructural Response of Variably Hydrated Ca-Rich Montmorillonite...
Microstructural Response of Variably Hydrated Ca-Rich Montmorillonite to Supercritical CO2. Microstructural Response of Variably Hydrated Ca-Rich Montmorillonite to Supercritical...
Dynamic simulation of a proposed ITER tritium processing system
Dynamically simulating the fuel cycle in a fusion reactor is crucial to developing a better understanding of the safe and reliable operation of this complex system. In this work, we propose a tritium processing system for ITER`s plasma exhaust. The dynamic simulation of this proposed system is then performed with the TRUFFLES (TRitiUm Fusion Fuel cycLE dynamic Simulation) model. The fuel management, storage, and fueling operations are developed and coupled with previous cryopump and fuel cleanup unit subsystems to fully realize the complete torus exhaust flow cycle. Results show that tritium inventories will vary widely depending upon reactor operation, individual subsystem and unit operation designs. A diverse collection of batch-controlled subsystems with changes in their processing parameters are simulated in this work. In particular, the effects from the fuel management subsystem`s fuel reserve and tank switching times are quantified using sensitivity studies. 6 refs., 10 figs., 2 tabs.
Kuan, W.; Abdou, M.A. [Univ. of California, Los Angeles, CA (United States); Scott W.R. [Los Alamos National Lab., NM (United States)
Effect of Fuel System Impedance Mismatch on Combustion Dynamics
Combustion dynamics are a challenging problem in the design and operation of premixed gas turbine combustors. In premixed combustors, pressure oscillations created by the flame dynamic response can lead to damage. These dynamics are typically controlled by designing the combustor to achieve a stable operation for planned conditions, but dynamics may still occur with minor changes in ambient operating conditions or fuel composition. In these situations, pilot flames or adjustment to fuel flow splits can be used to stabilize the combustor, but often with a compromise in emission performance. As an alternative to purely passive design changes, prior studies have demonstrated that adjustment to the fuel system impedance can be used to stabilize combustion. Prior studies have considered just the response of an individual fuel injector and combustor. However, in practical combustion systems, multiple fuel injectors are used. In this situation, individual injector impedance can be modified to produce a different dynamic response from individual flames. The resulting impedance mismatch prevents all injectors from strongly coupling to the same acoustic mode. In principle, this mismatch should reduce the amplitude of dynamics and may expand the operating margin for stable combustion conditions. In this paper, a 30 kW laboratory combustor with two premixed fuel injectors is used to study the effect of impedance mismatch on combustion stability. The two fuel injectors are equipped with variable geometry resonators that allow a survey of dynamic stability while changing the impedance of the individual fuel systems. Results demonstrate that a wide variation in dynamic response can be achieved by combining different impedance fuel injectors. A base line 7% rms pressure oscillation was reduced to less than 3% by mismatching the fuel impedance.
Richards, G.A.; Robey, E.H.
Dynamics of harmonically-confined systems: Some rigorous results
In this paper we consider the dynamics of harmonically-confined atomic gases. We present various general results which are independent of particle statistics, interatomic interactions and dimensionality. Of particular interest is the response of the system to external perturbations which can be either static or dynamic in nature. We prove an extended Harmonic Potential Theorem which is useful in determining the damping of the centre of mass motion when the system is prepared initially in a highly nonequilibrium state. We also study the response of the gas to a dynamic external potential whose position is made to oscillate sinusoidally in a given direction. We show in this case that either the energy absorption rate or the centre of mass dynamics can serve as a probe of the optical conductivity of the system. -- Highlights: �We derive various rigorous results on the dynamics of harmonically-confined atomic gases. �We derive an extension of the Harmonic Potential Theorem. �We demonstrate the link between the energy absorption rate in a harmonically-confined system and the optical conductivity.
Wu, Zhigang, E-mail: email@example.com; Zaremba, Eugene, E-mail: firstname.lastname@example.com
Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is in the final stages of a cost-shared partnership between Maurer Technology, Noble Corporation, Anadarko Petroleum, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. Hot Ice No. 1 was planned to test the Ugnu and West Sak sequences for gas hydrates and a concomitant free gas accumulation on Anadarko's 100% working interest acreage in section 30 of Township 9N, Range 8E of the Harrison Bay quadrangle of the North Slope of Alaska. The Ugnu and West Sak intervals are favorably positioned in the hydrate-stability zone over an area extending from Anadarko's acreage westward to the vicinity of the aforementioned gas-hydrate occurrences. This suggests that a large, north-to-south trending gas-hydrate accumulation may exist in that area. The presence of gas shows in the Ugnu and West Sak reservoirs in wells situated eastward and down dip of the Hot Ice location indicate that a free-gas accumulation may be trapped by gas hydrates. The Hot Ice No. 1 well was designed to core from the surface to the base of the West Sak interval using the revolutionary and new Arctic Drilling Platform in search of gas hydrate and free gas accumulations at depths of approximately 1200 to 2500 ft MD. A secondary objective was the gas-charged sands of the uppermost Campanian interval at approximately 3000 ft. Summary results of geophysical analysis of the well are presented in this report.
Donn McGuire; Steve Runyon; Richard Sigal; Bill Liddell; Thomas Williams; George Moridis
Efficiency of Charge Transport in a Polypeptide Chain: The Hydrated System Sheh-Yi Sheu,*, Dah-Yen Yang,*, H. L. Selzle,| and E. W. Schlag*,|
there is very little attenuation observed. We here do extensive molecular dynamics calculations in the presenceVersity, Taipei 112, Taiwan, Institute of Atomic and Molecular Science, Academia Sinica, Taipei 106, Taiwan the original site of excitation and is typical in biological signal transduction. This model introduced
Sheu, Sheh-Yi
Novel coupling scheme to control dynamics of coupled discrete systems
We present a new coupling scheme to control spatio-temporal patterns and chimeras on 1-d and 2-d lattices and random networks of discrete dynamical systems. The scheme involves coupling with an external lattice or network of damped systems. When the system network and external network are set in a feedback loop, the system network can be controlled to a homogeneous steady state or synchronized periodic state with suppression of the chaotic dynamics of the individual units. The control scheme has the advantage that its design does not require any prior information about the system dynamics or its parameters and works effectively for a range of parameters of the control network. We analyze the stability of the controlled steady state or amplitude death state of lattices using the theory of circulant matrices and Routh-Hurwitz's criterion for discrete systems and this helps to isolate regions of effective control in the relevant parameter planes. The conditions thus obtained are found to agree well with those obtained from direct numerical simulations in the specific context of lattices with logistic map and Henon map as on-site system dynamics. We show how chimera states developed in an experimentally realizable 2-d lattice can be controlled using this scheme. We propose this mechanism can provide a phenomenological model for the control of spatio-temporal patterns in coupled neurons due to non-synaptic coupling with the extra cellular medium. We extend the control scheme to regulate dynamics on random networks and adapt the master stability function method to analyze the stability of the controlled state for various topologies and coupling strengths.
Snehal M. Shekatkar; G. Ambika
Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is in the final stages of a cost shared partnership between Maurer Technology, Noble Corporation, Anadarko Petroleum, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. The work scope drilled and cored a well The HOT ICE No.1 on Anadarko leases beginning in FY 2003 and completed in 2004. An on-site core analysis laboratory was built and utilized for determining the physical characteristics of the hydrates and surrounding rock. The well was drilled from a new Anadarko Arctic Platform that has a minimal footprint and environmental impact. The final efforts of the project are to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists developing reservoir models. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in this report.
Thomas E. Williams; Keith Millheim; Buddy King
Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Oil-field engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in Arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrates agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is a cost-shared partnership between Maurer Technology, Anadarko Petroleum, Noble Corporation, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to help identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. As part of the project work scope, team members drilled and cored the HOT ICE No. 1 on Anadarko leases beginning in January 2003 and completed in March 2004. Due to scheduling constraints imposed by the Arctic drilling season, operations at the site were suspended between April 21, 2003 and January 30, 2004. An on-site core analysis laboratory was designed, constructed and used for determining physical characteristics of frozen core immediately after it was retrieved from the well. The well was drilled from a new and innovative Anadarko Arctic Platform that has a greatly reduced footprint and environmental impact. Final efforts of the project were to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists for future hydrate operations. Unfortunately, no gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in the project reports.
Thomas E. Williams; Keith Millheim; Bill Liddell
Overview on Hydrate Coring, Handling and Analysis
Gas hydrates are crystalline, ice-like compounds of gas and water molecules that are formed under certain thermodynamic conditions. Hydrate deposits occur naturally within ocean sediments just below the sea floor at temperatures and pressures existing below about 500 meters water depth. Gas hydrate is also stable in conjunction with the permafrost in the Arctic. Most marine gas hydrate is formed of microbially generated gas. It binds huge amounts of methane into the sediments. Worldwide, gas hydrate is estimated to hold about 1016 kg of organic carbon in the form of methane (Kvenvolden et al., 1993). Gas hydrate is one of the fossil fuel resources that is yet untapped, but may play a major role in meeting the energy challenge of this century. In June 2002, Westport Technology Center was requested by the Department of Energy (DOE) to prepare a ''Best Practices Manual on Gas Hydrate Coring, Handling and Analysis'' under Award No. DE-FC26-02NT41327. The scope of the task was specifically targeted for coring sediments with hydrates in Alaska, the Gulf of Mexico (GOM) and from the present Ocean Drilling Program (ODP) drillship. The specific subjects under this scope were defined in 3 stages as follows: Stage 1: Collect information on coring sediments with hydrates, core handling, core preservation, sample transportation, analysis of the core, and long term preservation. Stage 2: Provide copies of the first draft to a list of experts and stakeholders designated by DOE. Stage 3: Produce a second draft of the manual with benefit of input from external review for delivery. The manual provides an overview of existing information available in the published literature and reports on coring, analysis, preservation and transport of gas hydrates for laboratory analysis as of June 2003. The manual was delivered as draft version 3 to the DOE Project Manager for distribution in July 2003. This Final Report is provided for records purposes.
Jon Burger; Deepak Gupta; Patrick Jacobs; John Shillinglaw
Optimal Control of Building HVAC Systems in the Presence of Imperfect Predictions, ASME Dynamic System Control Conference
optimal control design for HVAC systems,� in Dynamic Systemalgorithm design for hvac systems in energy efficient build-OPTIMAL CONTROL OF BUILDING HVAC SYSTEMS IN THE PRESENCE OF
Maasoumy, Mehdi
Determining the role of hydration forces in protein folding
One of the primary issues in protein folding is determining what forces drive folding and eventually stabilize the native state. A delicate balance exists between electrostatic forces such as hydrogen bonding and salt bridges, and the hydrophobic effect, which are present for both intramolecular protein interactions and intermolecular contributions with the surrounding aqueous environment. This article describes a combined experimental, theoretical, and computational effort to show how the complexity of aqueous hydration can influence the structure, folding and aggregation, and stability of model protein systems. The unification of the theoretical and experimental work is the development or discovery of effective amino acid interactions that implicitly include the effects of aqueous solvent. The authors show that consideration of the full range of complexity of aqueous hydration forces such as many-body effects, long-ranged character of aqueous solvation, and the assumptions made about the degree of protein hydrophobicity can directly impact the observed structure, folding, and stability of model protein systems.
Sorenson, J.M. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry] [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry; Hura, G. [Univ. of California, Berkeley, CA (United States)] [Univ. of California, Berkeley, CA (United States); [Lawrence Berkeley National Lab., CA (United States). Life Sciences Div.; Soper, A.K. [Rutherford Appleton Lab., Didcot (United Kingdom). ISIS Facility] [Rutherford Appleton Lab., Didcot (United Kingdom). ISIS Facility; Pertsemlidis, A. [Univ. of Texas Southwestern Medical Center, Dallas, TX (United States). Dept. of Biochemistry] [Univ. of Texas Southwestern Medical Center, Dallas, TX (United States). Dept. of Biochemistry; Head-Gordon, T. [Lawrence Berkeley National Lab., CA (United States)] [Lawrence Berkeley National Lab., CA (United States)
Diffuse-Charge Dynamics in Electrochemical Systems
The response of a model micro-electrochemical system to a time-dependent applied voltage is analyzed. The article begins with a fresh historical review including electrochemistry, colloidal science, and microfluidics. The model problem consists of a symmetric binary electrolyte between parallel-plate, blocking electrodes which suddenly apply a voltage. Compact Stern layers on the electrodes are also taken into account. The Nernst-Planck-Poisson equations are first linearized and solved by Laplace transforms for small voltages, and numerical solutions are obtained for large voltages. The ``weakly nonlinear'' limit of thin double layers is then analyzed by matched asymptotic expansions in the small parameter $\\epsilon = \\lambda_D/L$, where $\\lambda_D$ is the screening length and $L$ the electrode separation. At leading order, the system initially behaves like an RC circuit with a response time of $\\lambda_D L / D$ (not $\\lambda_D^2/D$), where $D$ is the ionic diffusivity, but nonlinearity violates this common picture and introduce multiple time scales. The charging process slows down, and neutral-salt adsorption by the diffuse part of the double layer couples to bulk diffusion at the time scale, $L^2/D$. In the ``strongly nonlinear'' regime (controlled by a dimensionless parameter resembling the Dukhin number), this effect produces bulk concentration gradients, and, at very large voltages, transient space charge. The article concludes with an overview of more general situations involving surface conduction, multi-component electrolytes, and Faradaic processes.
Martin Z. Bazant; Katsuyo Thornton; Armand Ajdari
Left invertibility, flatness and identifiability of switched linear dynamical systems: a framework
Left invertibility, flatness and identifiability of switched linear dynamical systems: a framework invertibility and flatness, dynamical systems are structurally equivalent to some specific cryptographic invertibility, flatness and identifiability of discrete- time switched linear systems are investigated
Methane Recovery from Hydrate-bearing Sediments
Gas hydrates are crystalline compounds made of gas and water molecules. Methane hydrates are found in marine sediments and permafrost regions; extensive amounts of methane are trapped in the form of hydrates. Methane hydrate can be an energy resource, contribute to global warming, or cause seafloor instability. This study placed emphasis on gas recovery from hydrate bearing sediments and related phenomena. The unique behavior of hydrate-bearing sediments required the development of special research tools, including new numerical algorithms (tube- and pore-network models) and experimental devices (high pressure chambers and micromodels). Therefore, the research methodology combined experimental studies, particle-scale numerical simulations, and macro-scale analyses of coupled processes. Research conducted as part of this project started with hydrate formation in sediment pores and extended to production methods and emergent phenomena. In particular, the scope of the work addressed: (1) hydrate formation and growth in pores, the assessment of formation rate, tensile/adhesive strength and their impact on sediment-scale properties, including volume change during hydrate formation and dissociation; (2) the effect of physical properties such as gas solubility, salinity, pore size, and mixed gas conditions on hydrate formation and dissociation, and it implications such as oscillatory transient hydrate formation, dissolution within the hydrate stability field, initial hydrate lens formation, and phase boundary changes in real field situations; (3) fluid conductivity in relation to pore size distribution and spatial correlation and the emergence of phenomena such as flow focusing; (4) mixed fluid flow, with special emphasis on differences between invading gas and nucleating gas, implications on relative gas conductivity for reservoir simulations, and gas recovery efficiency; (5) identification of advantages and limitations in different gas production strategies with emphasis; (6) detailed study of CH4-CO2 exchange as a unique alternative to recover CH4 gas while sequestering CO2; (7) the relevance of fines in otherwise clean sand sediments on gas recovery and related phenomena such as fines migration and clogging, vuggy structure formation, and gas-driven fracture formation during gas production by depressurization.
J. Carlos Santamarina; Costas Tsouris
The flashing ratchet: long time behavior and dynamical systems interpretation
The flashing ratchet: long time behavior and dynamical systems interpretation Jean email@example.com December 11, 2002 Abstract. The flashing ratchet is a model for certain types of molecular motors as well then study the long time behavior of the flashing ratchet model. By entropy methods, we prove the existence
Dolbeault, Jean
The Center for Control, Dynamical Systems, and Computation Spring Seminars
The Center for Control, Dynamical Systems, and Computation Spring Seminars Presents Plasma Control, is magnetically confined through electromagnetic fields generated by a set of `'poloidal field'' coils distributed around the vacuum vessel. Voltages are applied to these coils which drive coil currents inducing
Akhmedov, Azer
Innovation system dynamics and sustainable development Challenges for policy
Innovation system dynamics and sustainable development � Challenges for policy Paper in progress Innovation, Sustainability and Policy Conference, 23-25 May 2004 Kloster Seeon, Germany Dr. Maj Munch, while market development perspectives are neglected. The NIS perspective forwarded in this paper has
(thermal, gas, diesel) and renewable (hydro, wind) power units. The objective is to assess the impact - that have a special dynamic behaviour, and the wind turbines. Detailed models for each one of the power system components are developed. Emphasis is given in the representation of different hydro power plant
Vehicle System Dynamics Vol. 00, No. 00, April 2008, 129
Vehicle System Dynamics Vol. 00, No. 00, April 2008, 1�29 Fidelity of using scaled vehicles (April 2008) There are many situations where physical testing of a vehicle or vehicle controller is necessary, yet use of a full-size vehicle is not practical. Some situations include implementation testing
Brennan, Sean
FRW Cosmological model with Modified Chaplygin Gas and Dynamical System
The Friedmann-Robertson-Walker(FRW) model with dynamical Dark Energy(DE) in the form of modified Chaplygin gas(MCG) has been investigated. The evolution equations are reduced to an autonomous system on the two dimensional phase plane and it can be interpreted as the motion of the particle in an one dimensional potential.
Nairwita Mazumder; Ritabrata Biswas; Subenoy Chakraborty
Seminar -1. letnik, II. stopnja Memristive system vacancies dynamics
Seminar - 1. letnik, II. stopnja Memristive system vacancies dynamics Klemen Zelic Mentor: Prof. Dr of ionic crystal - TiO2 . . . . . . . . . . . . . . . . . 3 3 Doped ionic crystal 3 3.1 Vacancy doped . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4.2 Diffusion with vacancies interaction . . . . . . . . . . . . . . . 11 4.2.1 vacancies
�?umer, Slobodan
Optimal PMU Placement Evaluation for Power System Dynamic State Estimation
Abstract - The synchronized phaor measurements unit (PMU), developed in the 1980s, is concidered to be one of the most important devices in the future of power systems. The recent development of PMU technology provides high-speed, precisely synchronized sensor data, which has been found to be usefule for dynamic, state estimation of power the power grid.
Zhang, Jinghe; Welch, Greg; Bishop, Gary; Huang, Zhenyu
The evolutionary dynamics of self-incompatibility systems
The evolutionary dynamics of self-incompatibility systems Ed Newbigin1 and Marcy K. Uyenoyama2 1, Duke University, Durham, NC 27708-0338, USA Self-incompatible flowering plants reject pollen, pollen and pistil mating specificities segregate as a single locus, the S locus. In at least two self-incompat
Uyenoyama, Marcy K
Dynamics of a Simple Quantum System in a Complex Environment
We present a theory for the dynamical evolution of a quantum system coupled to a complex many-body intrinsic system/environment. By modelling the intrinsic many-body system with parametric random matrices, we study the types of effective stochastic models which emerge from random matrix theory. Using the Feynman-Vernon path integral formalism, we derive the influence functional and obtain either analytical or numerical solutions for the time evolution of the entire quantum system. We discuss thoroughly the structure of the solutions for some representative cases and make connections to well known limiting results, particularly to Brownian motion, Kramers classical limit and the Caldeira-Leggett approach.
Aurel Bulgac; Gui DoDang; Dimitri Kusnezov
Nuclear Hybrid Energy System Modeling: RELAP5 Dynamic Coupling Capabilities
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.
Piyush Sabharwall; Nolan Anderson; Haihua Zhao; Shannon Bragg-Sitton; George Mesina
Characterizing quantum dynamics with initial system-environment correlations
We fully characterize the reduced dynamics of an open quantum system initially correlated with its environment. Using a photonic qubit coupled to a simulated environment we tomographically reconstruct a superchannel---a generalised channel that treats preparation procedures as inputs---from measurement of the system alone, despite its coupling to the environment. We introduce novel quantitative measures for determining the strength of initial correlations, and to allow an experiment to be optimised in regards to its environment.
Martin Ringbauer; Christopher J. Wood; Kavan Modi; Alexei Gilchrist; Andrew G. White; Alessandro Fedrizzi
Relativistic Quantum Metrology in Open System Dynamics
Quantum metrology studies the ultimate limit of precision in estimating a physical quantity if quantum strategies are exploited. Here we investigate the evolution of a two-level atom as a detector which interacts with a massless scalar field using the master equation approach for open quantum system. We employ local quantum estimation theory to estimate the Unruh temperature when probed by a uniformly accelerated detector in the Minkowski vacuum. In particular, we evaluate the Fisher information (FI) for population measurement, maximize its value over all possible detector preparations and evolution times, and compare its behavior with that of the quantum Fisher information (QFI). We find that the optimal precision of estimation is achieved when the detector evolves for a long enough time. Furthermore, we find that in this case the FI for population measurement is independent of initial preparations of the detector and is exactly equal to the QFI, which means that population measurement is optimal. This result demonstrates that the achievement of the ultimate bound of precision imposed by quantum mechanics is possible. Finally, we note that the same configuration is also available to the maximum of the QFI itself.
Zehua Tian; Jieci Wang; Heng Fan; Jiliang Jing
Gas Hydrates Research Programs: An International Review
Gas hydrates sediments have the potential of providing a huge amount of natural gas for human use. Hydrate sediments have been found in many different regions where the required temperature and pressure conditions have been satisfied. Resource exploitation is related to the safe dissociation of the gas hydrate sediments. Basic depressurization techniques and thermal stimulation processes have been tried in pilot efforts to exploit the resource. There is a growing interest in gas hydrates all over the world due to the inevitable decline of oil and gas reserves. Many different countries are interested in this valuable resource. Unsurprisingly, developed countries with limited energy resources have taken the lead in worldwide gas hydrates research and exploration. The goal of this research project is to collect information in order to record and evaluate the relative strengths and goals of the different gas hydrates programs throughout the world. A thorough literature search about gas hydrates research activities has been conducted. The main participants in the research effort have been identified and summaries of their past and present activities reported. An evaluation section discussing present and future research activities has also been included.
Jorge Gabitto; Maria Barrufet
FORMAL SEMANTICS AND VERIFICATION OF DYNAMIC RELIABILITY BLOCK DIAGRAMS FOR SYSTEM RELIABILITY captured by existing reliability modeling tools. In this paper, we introduce a new reliability modeling tool, called dynamic reliability block diagrams (DRBD), for modeling dynamic relationships between
Xu, Haiping
Power Systems Frequency Dynamic Monitoring System Design and Applications
Disturbance Recorder (FDR), Phasor Measurement Unit (PMU), Wide Area Measurement System, Under Frequency Load Management System (IMS) to work as a central server to process the frequency data. The device comparison between FDR and commercial PMU (Phasor Measurement Unit) demonstrate the advantage of FNET. The web
Schrijver, Karel
Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the US have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is in the second year of a three-year endeavor being sponsored by maurer Technology, noble, and Anadarko Petroleum, in partnership with the DOE. The purpose of the project is to build on previous and ongoing R and D in the area of onshore hydrate deposition. They plan to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. They also plan to design and implement a program to safely and economically drill, core and produce gas from arctic hydrates. The current work scope is to drill and core a well on Anadarko leases in FY 2003 and 2004. They are also using an on-site core analysis laboratory to determine some of the physical characteristics of the hydrates and surrounding rock. The well is being drilled from a new Anadarko Arctic Platform that will have minimal footprint and environmental impact. They hope to correlate geology, geophysics, logs, and drilling and production data to allow reservoir models to be calibrated. Ultimately, the goal is to form an objective technical and economic evaluation of reservoir potential in Alaska.
Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is in the second year of a three-year endeavor being sponsored by Maurer Technology, Noble, and Anadarko Petroleum, in partnership with the DOE. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition. We plan to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. We also plan to design and implement a program to safely and economically drill, core and produce gas from arctic hydrates. The current work scope is to drill and core a well on Anadarko leases in FY 2003 and 2004. We are also using an on-site core analysis laboratory to determine some of the physical characteristics of the hydrates and surrounding rock. The well is being drilled from a new Anadarko Arctic Platform that will have minimal footprint and environmental impact. We hope to correlate geology, geophysics, logs, and drilling and production data to allow reservoir models to be calibrated. Ultimately, our goal is to form an objective technical and economic evaluation of reservoir potential in Alaska.
Department of Energy Advance Methane Hydrates Science and Technology Projects
Broader source: Energy.gov [DOE]
Descriptions for Energy Department Methane Hydrates Science and Technology Projects, August 31, 2012
Effectiveness of Alcohol Cosurfactants in Hydrate Antiagglomeration Minwei Sun,
and deepwater oil capture. One of the most effective methods to address gas hydrate problems is through-in-water emulsions, therefore enhancing the hydrate antiagglomeration effect. 1. INTRODUCTION Gas hydrates, especially in the deep sea, formation of gas hydrates may plug flowlines.1 There are significant safety
Econophysical Dynamics of Market-Based Electric Power Distribution Systems
As energy markets begin clearing at sub-hourly rates, their interaction with load control systems becomes a potentially important consideration. A simple model for the control of thermal systems using market-based power distribution strategies is proposed, with particular attention to the behavior and dynamics of electric building loads and distribution-level power markets. Observations of dynamic behavior of simple numerical model are compared to that of an aggregate continuous model. The analytic solution of the continuous model suggests important deficiencies in each. The continuous model provides very valuable insights into how one might design such load control system and design the power markets they interact with. We also highlight important shortcomings of the continuous model which we believe must be addressed using discrete models.
Nicolas Ho; David P. Chassin
Meeting Residential Ventilation Standards Through Dynamic Control of Ventilation Systems
Existing ventilation standards, including American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE) Standard 62.2, specify continuous operation of a defined mechanical ventilation system to provide minimum ventilation, with time-based intermittent operation as an option. This requirement ignores several factors and concerns including: other equipment such as household exhaust fans that might incidentally provide ventilation, negative impacts of ventilation when outdoor pollutant levels are high, the importance of minimizing energy use particularly during times of peak electricity demand, and how the energy used to condition air as part of ventilation system operation changes with outdoor conditions. Dynamic control of ventilation systems can provide ventilation equivalent to or better than what is required by standards while minimizing energy costs and can also add value by shifting load during peak times and reducing intake of outdoor air contaminants. This article describes the logic that enables dynamic control of whole-house ventilation systems to meet the intent of ventilation standards and demonstrates the dynamic ventilation system control concept through simulations and field tests of the Residential Integrated Ventilation-Energy Controller (RIVEC).
Sherman, Max H.; Walker, Iain S.
Semiclassical quantization of non-Hamiltonian dynamical systems without memory
We propose a new method of quantization of a wide class of dynamical systems that originates directly from the equations of motion. The method is based on the correspondence between the classical and the quantum Poisson brackets, postulated by Dirac. This correspondence applied to open (non-Hamiltonian) systems allows one to point out the way of transition from the quantum description based on the Lindblad equation to the dynamical description of their classical analogs by the equations of motion and vice versa. As the examples of using of the method we describe the procedure of the quantization of three widely considered dynamical systems: (1) the harmonic oscillator with friction (2) the oscillator with a nonlinear damping that simulates the process of the emergence of the limit cycle, and (3) the system of two periodic rotators with a weak interaction that synchronizes their oscillations. We discuss a possible application of the method for a description of quantum fluctuations in Josephson junctions with a strong damping and for the quantization of open magnetic systems with a dissipation and a pumping.
Vol, E. D. [B. Verkin Institute for Low Temperature Physics and Engineering National Academy of Sciences of Ukraine, Lenin av. 47 Kharkov 61103 (Ukraine)
A molecular dynamics study of polymer/graphene interfacial systems
Graphene based polymer nanocomposites are hybrid materials with a very broad range of technological applications. In this work, we study three hybrid polymer/graphene interfacial systems (polystyrene/graphene, poly(methyl methacrylate)/graphene and polyethylene/graphene) through detailed atomistic molecular dynamics (MD) simulations. Density profiles, structural characteristics and mobility aspects are being examined at the molecular level for all model systems. In addition, we compare the properties of the hybrid systems to the properties of the corresponding bulk ones, as well as to theoretical predictions.
Rissanou, Anastassia N.; Harmandaris, Vagelis [Department of Mathematics and Applied Mathematics, University of Crete, GR-71409, Heraklion, Crete, Greece and Institute of Applied and Computational Mathematics (IACM), Foundation for Research and Technology Hellas (FORTH), GR-71110, Heraklion, Cret (Greece)
Prony Analysis is a technique used to decompose a signal into a series consisting of weighted complex exponentials and promises to be an effi cient way of recognizing sensitive lines during faults in power systems such as the U.S. Power grid. Positive Sequence Load Flow (PSLF) was used to simulate the performance of a simple two-area-four-generator system and the reaction of the system during a line fault. The Dynamic System Identifi cation (DSI) Toolbox was used to perform Prony analysis and use modal information to identify key transmission lines for power fl ow adjustment to improve system damping. The success of the application of Prony analysis methods to the data obtained from PSLF is reported, and the key transmission line for adjustment is identifi ed. Future work will focus on larger systems and improving the current algorithms to deal with networks such as large portions of the Western Electricity Coordinating Council (WECC) power grid.
Ray, C.; Huang, Z.
A realistic molecular model of cement hydrates
Despite decades of studies of calcium-silicate-hydrate (C-S-H), the structurally complex binder phase of concrete, the interplay between chemical composition and density remains essentially unexplored. Together these ...
Ulm, Franz-Josef
ConocoPhillips Gas Hydrate Production Test
Work began on the ConocoPhillips Gas Hydrates Production Test (DOE award number DE-NT0006553) on October 1, 2008. This final report summarizes the entire project from January 1, 2011 to June 30, 2013.
Schoderbek, David; Farrell, Helen; Howard, James; Raterman, Kevin; Silpngarmlert, Suntichai; Martin, Kenneth; Smith, Bruce; Klein, Perry
Hydrate Control for Gas Storage Operations
The overall objective of this project was to identify low cost hydrate control options to help mitigate and solve hydrate problems that occur in moderate and high pressure natural gas storage field operations. The study includes data on a number of flow configurations, fluids and control options that are common in natural gas storage field flow lines. The final phase of this work brings together data and experience from the hydrate flow test facility and multiple field and operator sources. It includes a compilation of basic information on operating conditions as well as candidate field separation options. Lastly the work is integrated with the work with the initial work to provide a comprehensive view of gas storage field hydrate control for field operations and storage field personnel.
Jeffrey Savidge
Weakening of ice by magnesium perchlorate hydrate
I show that perchlorate hydrates, which have been indirectly detected at high Martian circumpolar latitudes by the Phoenix Mars Lander, have a dramatic effect upon the rheological behavior of polycrystalline water ice under ...
Lenferink, Hendrik J., 1985-
Modeling of gas hydrates from first principles
Ab initio calculations were used to determine the H20-CH4 potential energy surface (PES) accurately for use in modeling gas hydrates. Electron correlation was found to be treated accurately by the second-order Moller-Plesset ...
Cao, Zhitao, 1974-
Photoelectron Spectroscopy of Cold Hydrated Sulfate Clusters...
sulfate clusters SO42-(H2O)n (n ) 4-7) at 12 K and ab initio studies to understand the structures and dynamics of these unique solvated systems. A significant increase of...
Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is a cost-shared partnership between Maurer Technology, Anadarko Petroleum, Noble Corporation, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to help identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. As part of the project work scope, team members drilled and cored a well (the Hot Ice No. 1) on Anadarko leases beginning in January 2003 and completed in March 2004. Due to scheduling constraints imposed by the Arctic drilling season, operations at the site were suspended between April 21, 2003 and January 30, 2004. An on-site core analysis laboratory was constructed and used for determining physical characteristics of frozen core immediately after it was retrieved from the well. The well was drilled from a new and innovative Anadarko Arctic Platform that has a greatly reduced footprint and environmental impact. Final efforts of the project were to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists for future hydrate operations. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in the project reports. Documenting the results of this effort are key to extracting lessons learned and maximizing the industry's benefits for future hydrate exploitation. In addition to the Final Report, several companion Topical Reports are being published.
Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project was a cost-shared partnership between Maurer Technology, Noble Corporation, Anadarko Petroleum, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. The work scope included drilling and coring a well (Hot Ice No. 1) on Anadarko leases beginning in FY 2003 and completed in 2004. During the first drilling season, operations were conducted at the site between January 28, 2003 to April 30, 2003. The well was spudded and drilled to a depth of 1403 ft. Due to the onset of warmer weather, work was then suspended for the season. Operations at the site were continued after the tundra was re-opened the following season. Between January 12, 2004 and March 19, 2004, the well was drilled and cored to a final depth of 2300 ft. An on-site core analysis laboratory was built and implemented for determining physical characteristics of the hydrates and surrounding rock. The well was drilled from a new Anadarko Arctic Platform that has a minimal footprint and environmental impact. Final efforts of the project are to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists developing reservoir models and to research teams for developing future gas-hydrate projects. No gas hydrates were encountered in this well; however, a wealth of information was generated and has been documented by the project team. This Topical Report documents drilling and coring operations and other daily activities.
Ali Kadaster; Bill Liddell; Tommy Thompson; Thomas Williams; Michael Niedermayr
Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project was a cost-shared partnership between Maurer Technology, Noble Corporation, Anadarko Petroleum, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. The work scope included drilling and coring a well (Hot Ice No. 1) on Anadarko leases beginning in FY 2003 and completed in 2004. During the first drilling season, operations were conducted at the site between January 28, 2003 to April 30, 2003. The well was spudded and drilled to a depth of 1403 ft. Due to the onset of warmer weather, work was then suspended for the season. Operations at the site were continued after the tundra was re-opened the following season. Between January 12, 2004 and March 19, 2004, the well was drilled and cored to a final depth of 2300 ft. An on-site core analysis laboratory was built and utilized for determining the physical characteristics of the hydrates and surrounding rock. The well was drilled from a new Anadarko Arctic Platform that has a minimal footprint and environmental impact. The final efforts of the project are to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists planning hydrate exploration and development projects. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in this and other project reports. This Topical Report contains details describing logging operations.
Steve Runyon; Mike Globe; Kent Newsham; Robert Kleinberg; Doug Griffin
Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is a cost-shared partnership between Maurer Technology, Anadarko Petroleum, Noble Corporation, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to help identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. As part of the project work scope, team members drilled and cored a well (the Hot Ice No. 1) on Anadarko leases beginning in January 2003 and completed in March 2004. Due to scheduling constraints imposed by the Arctic drilling season, operations at the site were suspended between April 21, 2003 and January 30, 2004. An on-site core analysis laboratory was constructed and used for determining physical characteristics of frozen core immediately after it was retrieved from the well. The well was drilled from a new and innovative Anadarko Arctic Platform that has a greatly reduced footprint and environmental impact. Final efforts of the project were to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists for future hydrate operations. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in the project reports. Documenting the results of this effort are key to extracting lessons learned and maximizing the industry's benefits for future hydrate exploitation.
Electric Double-Layer Capacitor Based on an Ionic Clathrate Hydrate
Herein, we suggest a new approach to an electric double-layer capacitor (EDLC) that is based on a proton-conducting ionic clathrate hydrate (ICH). The ice-like structures of clathrate hydrates, which are comprised of host water molecules and guest ions, make them suitable for applications in EDLC electrolytes, owing to their high proton conductivities and thermal stabilities. The carbon materials in the ICH Me{sub 4}NOH[DOT OPERATOR]5?H{sub 2}O show a high specific capacitance, reversible charge�discharge behavior, and a long cycle life. The ionic-hydrate complex provides the following advantages in comparison with conventional aqueous and polymer electrolytes: 1)?The ICH does not cause leakage problems under normal EDLC operating conditions. 2)?The hydrate material can be utilized itself, without requiring any pre-treatments or activation for proton conduction, thus shortening the preparation procedure of the EDLC. 3)?The crystallization of the ICH makes it possible to tailor practical EDLC dimensions because of its fluidity as a liquid hydrate. 4)?The hydrate solid electrolyte exhibits more-favorable electrochemical stability than aqueous and polymer electrolytes. Therefore, ICH materials are expected to find practical applications in versatile energy devices that incorporate electrochemical systems.
Lee, Wonhee; Kwon, Minchul; Park, Seongmin; Lim, Dongwook Cha, Dr Jong-Ho; Lee, Dr. Huen
Generalized Performance of Concatenated Quantum Codes -- A Dynamical Systems Approach
We apply a dynamical systems approach to concatenation of quantum error correcting codes, extending and generalizing the results of Rahn et al. [1] to both diagonal and nondiagonal channels. Our point of view is global: instead of focusing on particular types of noise channels, we study the geometry of the coding map as a discrete-time dynamical system on the entire space of noise channels. In the case of diagonal channels, we show that any code with distance at least three corrects (in the infinite concatenation limit) an open set of errors. For Calderbank-Shor-Steane (CSS) codes, we give a more precise characterization of that set. We show how to incorporate noise in the gates, thus completing the framework. We derive some general bounds for noise channels, which allows us to analyze several codes in detail.
Jesse Fern; Julia Kempe; Slobodan Simic; Shankar Sastry
Particle confinement and Perturbed Dynamical System in Warped Product Spacetime
In this paper we have considered a five-dimensional warped product spacetime with spacelike extra dimension. We have decomposed the geodesic equations to get the motion along the extra dimension and have studied the dynamical system associated with it. The relation between the total energy along the phase path and the extra-dimensional coordinate have been established for different types of warping function and the nature of confinement of particle trajectories in these cases have been analyzed. We have also calculated the energy associated with the phase path under a linear coordinate perturbation independent of the affine parameter and have analyzed the nature of confinement and the geodesic motions in such a case. Finally, the stability of the dynamical system under a perturbation due to an extra-dimension dependent additional force and under the effect of scalar fields in the bulk, have been examined.
Pinaki Bhattacharya; Sarbari Guha
Quench Dynamics of Isolated Many-Body Quantum Systems
We study isolated quantum systems with two-body interactions after a quench. In these systems, the energy shell is a Gaussian of width $\\sigma$, and it gives the maximum possible spreading of the energy distribution of the initial states. When the distribution achieves this shape, the fidelity decay can be Gaussian until saturation. This establishes a lower bound for the fidelity decay in realistic systems. An ultimate bound for systems with many-body interactions is also derived based on the analysis of full random matrices. We find excellent agreement between numerical and analytical results. We also provide the conditions under which the short-time dynamics of few-body observables is controlled by $\\sigma$. The analyses are developed for systems, initial states, and observables accessible to experiments.
E. J. Torres-Herrera; Lea F. Santos
Presentations from the March 27th - 28th Methane Hydrates Advisory...
Broader source: Energy.gov (indexed) [DOE]
the March 27th - 28th Methane Hydrates Advisory Committee Meeting Presentations from the March 27th - 28th Methane Hydrates Advisory Committee Meeting International Gas Hydrate...
Strategies for gas production from hydrate accumulations under various geologic conditions
JNOC/GSC Mallik 2L- 38 Gas Hydrate Research Well, Mackenziedeposits. INTRODUCTION Gas hydrates are solid crystallinequantity of hydrocarbon gas hydrates range between 10 15 to
Moridis, G.; Collett, T.
Methane Hydrate Dissociation by Depressurization in a Mount Elbert Sandstone Sample: Experimental Observations and Numerical Simulations
DOE-USGS Mount Elbert gas hydrate stratigraphic test well:International Conference on Gas Hydrates, Vancouver, BritishGeologic controls on gas hydrate occurrence in the Mount
Kneafsey, T.
Gas production potential of disperse low-saturation hydrate accumulations in oceanic sediments
EG. Formation of gas hydrates in natural gas transmissiongeology of natural gas hydrates. Amsterdam: Springer-Verlag;Soloviev, VA. Submarine gas hydrates. St. Petersburg;1998.
Moridis, George J.; Sloan, E. Dendy
Thermal dissociation behavior and dissociation enthalpies of methane-carbon dioxide mixed hydrates
Dissociation heat of mixed-gas hydrate composed of methaneInternational Conference on Gas Hydrates (ICGH 2008), 2008,and specific heats of gas hydrates under submarine and
Kwon, T.H.
Feasibility of monitoring gas hydrate production with time-lapse VSP
density of the aqueous, gas, and hydrate phases, which isfunction of the aqueous, gas and hydrate phase saturations;in Marine Sediments with Gas Hydrates: Effective Medium
Kowalsky, M.B.
The effect of reservoir heterogeneity on gas production from hydrate accumulations in the permafrost
Spatial distributions of gas and hydrate phase saturations (from the Mallik 2002 Gas Hydrate Production Research Wellsimulating the behavior of gas hydrates, Energy Conversion
Reagan, M. T.
OTEC Cold Water Pipe-Platform Sub-System Dynamic Interaction...
OTEC Cold Water Pipe-Platform Sub-System Dynamic Interaction Validation (OPPSDIV) OTEC Cold Water Pipe-Platform Sub-System Dynamic Interaction Validation (OPPSDIV) OTEC Cold Water...
Dynamics of Josephson junction systems in the computational subspace
The quantum dynamics of the Josephson junction system in the computational subspace is investigated. A scheme for the controlled not operation is given for two capasitively coupled SQUIDs. In this system, there is no systematic error for the two qubit operation. For the inductively coupled SQUIDs, the effective Hamiltonian causes systematic errors in the computational subspace for the two qubit operation. Using the purterbation theory, we construct a more precise effective Hamiltonian. This new effective Hamiltonian reduces the systematic error to the level much lower than the threshold of the fault resilent quantum computation.
Wang Xiang-Bin; Matsumoto Keiji; Fan Heng; Y. Nakamura
Coupled Dynamic Modeling of Floating Wind Turbine Systems: Preprint
This article presents a collaborative research program that the Massachusetts Institute of Technology (MIT) and the National Renewable Energy Laboratory (NREL) have undertaken to develop innovative and cost-effective floating and mooring systems for offshore wind turbines in water depths of 10-200 m. Methods for the coupled structural, hydrodynamic, and aerodynamic analysis of floating wind turbine systems are presented in the frequency domain. This analysis was conducted by coupling the aerodynamics and structural dynamics code FAST [4] developed at NREL with the wave load and response simulation code WAMIT (Wave Analysis at MIT) [15] developed at MIT. Analysis tools were developed to consider coupled interactions between the wind turbine and the floating system. These include the gyroscopic loads of the wind turbine rotor on the tower and floater, the aerodynamic damping introduced by the wind turbine rotor, the hydrodynamic damping introduced by wave-body interactions, and the hydrodynamic forces caused by wave excitation. Analyses were conducted for two floater concepts coupled with the NREL 5-MW Offshore Baseline wind turbine in water depths of 10-200 m: the MIT/NREL Shallow Drafted Barge (SDB) and the MIT/NREL Tension Leg Platform (TLP). These concepts were chosen to represent two different methods of achieving stability to identify differences in performance and cost of the different stability methods. The static and dynamic analyses of these structures evaluate the systems' responses to wave excitation at a range of frequencies, the systems' natural frequencies, and the standard deviations of the systems' motions in each degree of freedom in various wind and wave environments. This article in various wind and wave environments. This article explores the effects of coupling the wind turbine with the floating platform, the effects of water depth, and the effects of wind speed on the systems' performance. An economic feasibility analysis of the two concepts was also performed. Key cost components included the material and construction costs of the buoy; material and installation costs of the tethers, mooring lines, and anchor technologies; costs of transporting and installing the system at the chosen site; and the cost of mounting the wind turbine to the platform. The two systems were evaluated based on their static and dynamic performance and the total system installed cost. Both systems demonstrated acceptable motions, and have estimated costs of $1.4-$1.8 million, not including the cost of the wind turbine, the power electronics, or the electrical transmission.
Wayman, E. N.; Sclavounos, P. D.; Butterfield, S.; Jonkman, J.; Musial, W.
Cognitive Information Processing, Greece, June 2008 (Haykin) 1 Cognitive Dynamic Systems
Cognitive Information Processing, Greece, June 2008 (Haykin) 1 Cognitive Dynamic Systems Simon. What is Cognition? 2. Cognitive Dynamic Systems Defined 3. Emerging Applications 4. Global Feedback 5. Why sub-optimality should be the objective of cognitive dynamic systems? 6. The Bayesian Filter
Haykin, Simon
Best practices for system dynamics model design and construction with powersim studio.
This guide addresses software quality in the construction of Powersim{reg_sign} Studio 8 system dynamics simulation models. It is the result of almost ten years of experience with the Powersim suite of system dynamics modeling tools (Constructor and earlier Studio versions). It is a guide that proposes a common look and feel for the construction of Powersim Studio system dynamics models.
Malczynski, Leonard A.
Power-laws in recurrence networks from dynamical systems
Recurrence networks are a novel tool of nonlinear time series analysis allowing the characterisation of higher-order geometric properties of complex dynamical systems based on recurrences in phase space, which are a fundamental concept in classical mechanics. In this Letter, we demonstrate that recurrence networks obtained from various deterministic model systems as well as experimental data naturally display power-law degree distributions with scaling exponents $\\gamma$ that can be derived exclusively from the systems' invariant densities. For one-dimensional maps, we show analytically that $\\gamma$ is not related to the fractal dimension. For continuous systems, we find two distinct types of behaviour: power-laws with an exponent $\\gamma$ depending on a suitable notion of local dimension, and such with fixed $\\gamma=1$.
Y. Zou; J. Heitzig; R. V. Donner; J. F. Donges; J. D. Farmer; R. Meucci; S. Euzzor; N. Marwan; J. Kurths
Assessment of dynamic energy conversion systems for radioisotope heat sources
The use of dynamic conversion systems to convert the heat generated in a 7500 W(t) 90 Sr radioisotopic heat source to electricity is examined. The systems studies were Stirling; Brayton Cycle; three organic Rankines (ORCs) (Barber-Nichols/ORMAT, Sundstrand, and TRW); and an organic Rankine plus thermoelectrics. The systems were ranked for a North Warning System mission using a Los Alamos Multiattribute Decision Theory code. Three different heat source designs were used: case I with a beginning of life (BOL) source temperature of 640 C, case II with a BOL source temperature of 745/sup 0/C, and case III with a BOL source temperature of 945/sup 0/C. The Stirling engine system was the top-ranked system of cases I and II, closely followed by the ORC systems in case I and ORC plus thermoelectrics in case II. The Brayton cycle system was top-ranked for case III, with the Stirling engine system a close second. The use of /sup 238/Pu in heat source sizes of 7500 W(t) was examined and found to be questionable because of cost and material availability and because of additional requirements for analysis of safeguards and critical mass.
Thayer, G.R.; Mangeng, C.A.
About one-third of the {approx}1200 transiting planet candidates detected in the first four months of Kepler data are members of multiple candidate systems. There are 115 target stars with two candidate transiting planets, 45 with three, 8 with four, and 1 each with five and six. We characterize the dynamical properties of these candidate multi-planet systems. The distribution of observed period ratios shows that the vast majority of candidate pairs are neither in nor near low-order mean-motion resonances. Nonetheless, there are small but statistically significant excesses of candidate pairs both in resonance and spaced slightly too far apart to be in resonance, particularly near the 2:1 resonance. We find that virtually all candidate systems are stable, as tested by numerical integrations that assume a nominal mass-radius relationship. Several considerations strongly suggest that the vast majority of these multi-candidate systems are true planetary systems. Using the observed multiplicity frequencies, we find that a single population of planetary systems that matches the higher multiplicities underpredicts the number of singly transiting systems. We provide constraints on the true multiplicity and mutual inclination distribution of the multi-candidate systems, revealing a population of systems with multiple super-Earth-size and Neptune-size planets with low to moderate mutual inclinations.
Lissauer, Jack J.; Jenkins, Jon M.; Borucki, William J.; Bryson, Stephen T.; Howell, Steve B. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Ragozzine, Darin; Holman, Matthew J.; Carter, Joshua A. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Fabrycky, Daniel C.; Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Steffen, Jason H. [Fermilab Center for Particle Astrophysics, Batavia, IL 60510 (United States); Ford, Eric B. [211 Bryant Space Science Center, University of Florida, Gainesville, FL 32611 (United States); Shporer, Avi [Las Cumbres Observatory Global Telescope Network, Santa Barbara, CA 93117 (United States); Rowe, Jason F.; Quintana, Elisa V.; Caldwell, Douglas A. [SETI Institute/NASA Ames Research Center, Moffett Field, CA 94035 (United States); Batalha, Natalie M. [Department of Physics and Astronomy, San Jose State University, San Jose, CA 95192 (United States); Ciardi, David [Exoplanet Science Institute/Caltech, Pasadena, CA 91125 (United States); Dunham, Edward W. [Lowell Observatory, Flagstaff, AZ 86001 (United States); Gautier, Thomas N. III, E-mail: email@example.com [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); and others
Application of Crunch-Flow Routines to Constrain Present and Past Carbon Fluxes at Gas-Hydrate Bearing Sites
In November 2012, Oregon State University initiated the project entitled: Application of Crunch-Flow routines to constrain present and past carbon fluxes at gas-hydrate bearing sites. Within this project we developed Crunch-Flow based modeling modules that include important biogeochemical processes that need to be considered in gas hydrate environments. Our modules were applied to quantify carbon cycling in present and past systems, using data collected during several DOE-supported drilling expeditions, which include the Cascadia margin in US, Ulleung Basin in South Korea, and several sites drilled offshore India on the Bay of Bengal and Andaman Sea. Specifically, we completed modeling efforts that: 1) Reproduce the compositional and isotopic profiles observed at the eight drilled sites in the Ulleung Basin that constrain and contrast the carbon cycling pathways at chimney (high methane flux) and non-chimney sites (low methane, advective systems); 2) Simulate the Ba record in the sediments to quantify the past dynamics of methane flux in the southern Hydrate Ridge, Cascadia margin; and 3) Provide quantitative estimates of the thickness of individual mass transport deposits (MTDs), time elapsed after the MTD event, rate of sulfate reduction in the MTD, and time required to reach a new steady state at several sites drilled in the Krishna-Godavari (K-G) Basin off India. In addition we developed a hybrid model scheme by coupling a home-made MATLAB code with CrunchFlow to address the methane transport and chloride enrichment at the Ulleung Basins chimney sites, and contributed the modeling component to a study focusing on pore-scale controls on gas hydrate distribution in sediments from the Andaman Sea. These efforts resulted in two manuscripts currently under review, and contributed the modeling component of another pare, also under review. Lessons learned from these efforts are the basis of a mini-workshop to be held at Oregon State University (Feb 2014) to instruct graduate students (OSU and UW) as well as DOE staff from the NETL lab in Albany on the use of Crunch Flow for geochemical applications.
Torres, Marta
Dynamical resonance locking in tidally interacting binary systems
We examine the dynamics of resonance locking in detached, tidally interacting binary systems. In a resonance lock, a given stellar or planetary mode is trapped in a highly resonant state for an extended period of time, during which the spin and orbital frequencies vary in concert to maintain the resonance. This phenomenon is qualitatively similar to resonance capture in planetary dynamics. We show that resonance locks can accelerate the course of tidal evolution in eccentric systems and also efficiently couple spin and orbital evolution in circular binaries. Previous analyses of resonance locking have not treated the mode amplitude as a fully dynamical variable, but rather assumed the adiabatic (i.e. Lorentzian) approximation valid only in the limit of relatively strong mode damping. We relax this approximation, analytically derive conditions under which the fixed point associated with resonance locking is stable, and further check these analytic results using numerical integrations of the coupled mode, spin, and orbital evolution equations. These show that resonance locking can sometimes take the form of complex limit cycles or even chaotic trajectories. We provide simple analytic formulae that define the binary and mode parameter regimes in which resonance locks of some kind occur (stable, limit cycle, or chaotic). We briefly discuss the astrophysical implications of our results for white dwarf and neutron star binaries as well as eccentric stellar binaries.
Joshua Burkart; Eliot Quataert; Phil Arras
Pressure-induced Hydration in Zeolite Tetranatrolite
The tetranatrolite-paranatrolite transformation has remained a key problem in understanding the paragenesis of zeolites in the natrolite family. It is accepted that when paranatrolite, approximate formula Na{sub 16-x}Ca{sub x}Al{sub 16+x}Si{sub 24-x}O{sub 80}{center_dot}24H{sub 2}O, is removed from an aqueous environment and exposed to the atmosphere, it loses water and transforms to tetranatrolite, Na{sub 16-x}Ca{sub x}Al{sub 16+x}Si{sub 24-x}O{sub 80}{center_dot}nH{sub 2}O (n {le} 24). Here we show that this transformation is not only reversible, but that tetranatrolite exhibits two sequential pressure-induced hydrations leading first to paranatrolite and then to a superhydrated tetranatrolite above 0.2 and 3.0 GPa, respectively. We have previously reported similar behavior for the corresponding system with an ordered Si/Al distribution, i.e., natrolite itself, however the ordered version of paranatrolite exists over a much smaller pressure range. The pressure-induced transformations of natrolite and tetranatrolite thus further supports the supposition that paranatrolite is a distinct mineral species, with a pressure-stability field dependent upon composition.
Lee,Y.; Hriljac, J.; Parise, J.; Vogt, T.
Complex admixtures of clathrate hydrates in a water desalination method
Disclosed is a method that achieves water desalination by utilizing and optimizing clathrate hydrate phenomena. Clathrate hydrates are crystalline compounds of gas and water that desalinate water by excluding salt molecules during crystallization. Contacting a hydrate forming gaseous species with water will spontaneously form hydrates at specific temperatures and pressures through the extraction of water molecules from the bulk phase followed by crystallite nucleation. Subsequent dissociation of pure hydrates yields fresh water and, if operated correctly, allows the hydrate-forming gas to be efficiently recycled into the process stream.
Simmons, Blake A. (San Francisco, CA); Bradshaw, Robert W. (Livermore, CA); Dedrick, Daniel E. (Berkeley, CA); Anderson, David W. (Riverbank, CA)
Dynamic Simulation and Optimization of Nuclear Hydrogen Production Systems
This project is part of a research effort to design a hydrogen plant and its interface with a nuclear reactor. This project developed a dynamic modeling, simulation and optimization environment for nuclear hydrogen production systems. A hybrid discrete/continuous model captures both the continuous dynamics of the nuclear plant, the hydrogen plant, and their interface, along with discrete events such as major upsets. This hybrid model makes us of accurate thermodynamic sub-models for the description of phase and reaction equilibria in the thermochemical reactor. Use of the detailed thermodynamic models will allow researchers to examine the process in detail and have confidence in the accurary of the property package they use.
Paul I. Barton; Mujid S. Kaximi; Georgios Bollas; Patricio Ramirez Munoz
System and method for reducing combustion dynamics in a combustor
A system for reducing combustion dynamics in a combustor includes an end cap having an upstream surface axially separated from a downstream surface, and tube bundles extend through the end cap. A diluent supply in fluid communication with the end cap provides diluent flow to the end cap. Diluent distributors circumferentially arranged inside at least one tube bundle extend downstream from the downstream surface and provide fluid communication for the diluent flow through the end cap. A method for reducing combustion dynamics in a combustor includes flowing fuel through tube bundles that extend axially through an end cap, flowing a diluent through diluent distributors into a combustion chamber, wherein the diluent distributors are circumferentially arranged inside at least one tube bundle and each diluent distributor extends downstream from the end cap, and forming a diluent barrier in the combustion chamber between at least one pair of adjacent tube bundles.
Uhm, Jong Ho; Johnson, Thomas Edward; Zuo, Baifang; York, William David
Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. The work scope drilled and cored a well The Hot Ice No. 1 on Anadarko leases beginning in FY 2003 and completed in 2004. An on-site core analysis laboratory was built and utilized for determining the physical characteristics of the hydrates and surrounding rock. The well was drilled from a new Anadarko Arctic Platform that has a minimal footprint and environmental impact. The final efforts of the project are to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists developing reservoir models. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in this report. The Hot Ice No. 1 well was drilled from the surface to a measured depth of 2300 ft. There was almost 100% core recovery from the bottom of surface casing at 107 ft to total depth. Based on the best estimate of the bottom of the methane hydrate stability zone (which used new data obtained from Hot Ice No. 1 and new analysis of data from adjacent wells), core was recovered over its complete range. Approximately 580 ft of porous, mostly frozen, sandstone and 155 of conglomerate were recovered in the Ugnu Formation and approximately 215 ft of porous sandstone were recovered in the West Sak Formation. There were gas shows in the bottom part of the Ugnu and throughout the West Sak. No hydrate-bearing zones were identified either in recovered core or on well logs. The base of the permafrost was found at about 1260 ft. With the exception of the deepest sands in the West Sak and some anomalous thin, tight zones, all sands recovered (after thawing) are unconsolidated with high porosity and high permeability. At 800 psi, Ugnu sands have an average porosity of 39.3% and geometrical mean permeability of 3.7 Darcys. Average grain density is 2.64 g/cc. West Sak sands have an average porosity of 35.5%, geometrical mean permeability of 0.3 Darcys, and average grain density of 2.70 g/cc. There were several 1-2 ft intervals of carbonate-cemented sandstone recovered from the West Sak. These intervals have porosities of only a few percent and very low permeability. On a well log they appear as resistive with a high sonic velocity. In shallow sections of other wells these usually are the only logs available. Given the presence of gas in Hot Ice No. 1, if only resistivity and sonic logs and a mud log had been available, tight sand zones may have been interpreted as containing hydrates. Although this finding does not imply that all previously mapped hydrate zones are merely tight sands, it does add a note of caution to the practice of interpreting the presence of hydrates from old well information. The methane hydrate stability zone below the Hot Ice No. 1 location includes thick sections of sandstone and conglomerate which would make excellent reservoir rocks for hydrates and below the permafrost zone shallow gas. The Ugnu formation comprises a more sand-rich section than does the West Sak formation, and the Ugnu sands when cleaned and dried are slightly more porous and significantly more permeable than the West Sak.
Richard Sigal; Kent Newsham; Thomas Williams; Barry Freifeld; Timothy Kneafsey; Carl Sondergeld; Shandra Rai; Jonathan Kwan; Stephen Kirby; Robert Kleinberg; Doug Griffin
Numerical, Laboratory And Field Studies of Gas Production From Natural Hydrate Accumulations in Geologic Media
hydrate (Class 1W) or gas and hydrate (Class 1G). In Class 1Economic Geology of Natural Gas Hydrates, M. Max, A.H. John-of the thermal test of gas hydrate dissociation in the
Moridis, George J.; Kneafsey, Timothy J.; Kowalsky, Michael; Reagan, Matthew
Depressurization-induced gas production from Class 1 and Class 2 hydrate deposits
hydrate (Class 1W) or gas and hydrate (Class 1G). In Class 1Class 1G (involving gas and hydrate in the HBL). In Class 2JNOC/GSC Mallik 2L-38 Gas Hydrate Research Well, Mackenzie
Moridis, George J.; Kowalsky, Michael
The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were (1) the preliminary postcruise evaluation of the tools and measurement systems that were used during ODP Leg 204 to study hydrate deposits on Hydrate Ridge, offshore Oregon from July through September 2002; and (2) the preliminary study of the hydrate-bearing core samples preserved in pressure vessels and in liquid nitrogen cryofreezers, which are now stored at the ODP Gulf Coast Repository in College Station, TX. During ODP Leg 204, several newly modified downhole tools were deployed to better characterize the subsurface lithologies and environments hosting microbial populations and gas hydrates. A preliminary review of the use of these tools is provided herein. The DVTP, DVTP-P, APC-methane, and APC-Temperature tools (ODP memory tools) were used extensively and successfully during ODP Leg 204 aboard the D/V JOIDES Resolution. These systems provided a strong operational capability for characterizing the in situ properties of methane hydrates in subsurface environments on Hydrate Ridge during ODP Leg 204. Pressure was also measured during a trial run of the Fugro piezoprobe, which operates on similar principles as the DVTP-P. The final report describing the deployments of the Fugro Piezoprobe is provided in Appendix A of this report. A preliminary analysis and comparison between the piezoprobe and DVTP-P tools is provided in Appendix B of this report. Finally, a series of additional holes were cored at the crest of Hydrate Ridge (Site 1249) specifically geared toward the rapid recovery and preservation of hydrate samples as part of a hydrate geriatric study partially funded by the Department of Energy (DOE). In addition, the preliminary results from gamma density non-invasive imaging of the cores preserved in pressure vessels are provided in Appendix C of this report. An initial visual inspection of the samples stored in liquid nitrogen is provided in Appendix D of this report.
Frank Rack; Michael Storms; Derryl Schroeder; Brandon Dugan; Peter Schultheiss; ODP Leg 204 Shipboard Scientific Party
Dynamic Systems Analysis Report for Nuclear Fuel Recycle
This report examines the time-dependent dynamics of transitioning from the current United States (U.S.) nuclear fuel cycle where used nuclear fuel is disposed in a repository to a closed fuel cycle where the used fuel is recycled and only fission products and waste are disposed. The report is intended to help inform policy developers, decision makers, and program managers of system-level options and constraints as they guide the formulation and implementation of advanced fuel cycle development and demonstration efforts and move toward deployment of nuclear fuel recycling infrastructure.
Brent Dixon; Sonny Kim; David Shropshire; Steven Piet; Gretchen Matthern; Bill Halsey
Dynamical Friction and Resonance Trapping in Planetary Systems
A restricted planar circular three-body system, consisting of the Sun and two planets, is studied as a simple model for a planetary system. The mass of the inner planet is considered to be larger and the system is assumed to be moving in a uniform interplanetary medium with constant density. Numerical integrations of this system indicate a resonance capture when the dynamical friction of the interplanetary medium is taken into account. As a result of this resonance trapping, the ratio of orbital periods of the two planets becomes nearly commensurate and the eccentricity and semimajor axis of the orbit of the outer planet and also its angular momentum and total energy become constant. It appears from the numerical work that the resulting commensurability and also the resonant values of the orbital elements of the outer planet are essentially independent of the initial relative positions of the two bodies. The results of numerical integrations of this system are presented and the first-order partially averaged equations are studied in order to elucidate the behavior of the system while captured in resonance.
Nader Haghighipour
Dynamic self-assembly in living systems as computation.
Biochemical reactions taking place in living systems that map different inputs to specific outputs are intuitively recognized as performing information processing. Conventional wisdom distinguishes such proteins, whose primary function is to transfer and process information, from proteins that perform the vast majority of the construction, maintenance, and actuation tasks of the cell (assembling and disassembling macromolecular structures, producing movement, and synthesizing and degrading molecules). In this paper, we examine the computing capabilities of biological processes in the context of the formal model of computing known as the random access machine (RAM) [Dewdney AK (1993) The New Turing Omnibus. Computer Science Press, New York], which is equivalent to a Turing machine [Minsky ML (1967) Computation: Finite and Infinite Machines. Prentice-Hall, Englewood Cliffs, NJ]. When viewed from the RAM perspective, we observe that many of these dynamic self-assembly processes - synthesis, degradation, assembly, movement - do carry out computational operations. We also show that the same computing model is applicable at other hierarchical levels of biological systems (e.g., cellular or organism networks as well as molecular networks). We present stochastic simulations of idealized protein networks designed explicitly to carry out a numeric calculation. We explore the reliability of such computations and discuss error-correction strategies (algorithms) employed by living systems. Finally, we discuss some real examples of dynamic self-assembly processes that occur in living systems, and describe the RAM computer programs they implement. Thus, by viewing the processes of living systems from the RAM perspective, a far greater fraction of these processes can be understood as computing than has been previously recognized.
Bouchard, Ann Marie; Osbourn, Gordon Cecil
Method for production of hydrocarbons from hydrates
A method of recovering natural gas entrapped in frozen subsurface gas hydrate formations in arctic regions. A hot supersaturated solution of CaCl.sub.2 or CaBr.sub.2, or a mixture thereof, is pumped under pressure down a wellbore and into a subsurface hydrate formation so as to hydrostatically fracture the formation. The CaCl.sub.2 /CaBr.sub.2 solution dissolves the solid hydrates and thereby releases the gas entrapped therein. Additionally, the solution contains a polymeric viscosifier, which operates to maintain in suspension finely divided crystalline CaCl.sub.2 /CaBr.sub.2 that precipitates from the supersaturated solution as it is cooled during injection into the formation.
McGuire, Patrick L. (Los Alamos, NM)
New Methane Hydrate Research: Investing in Our Energy Future...
Investing in Our Energy Future August 31, 2012 - 1:37pm Addthis Methane hydrates are 3D ice-lattice structures with natural gas locked inside. If methane hydrate is either warmed...
Detection of gas hydrates by the measurement of instantaneous temperature
Natural gas hydrates are icelike crystalline substances formed by gas molecules trapped in a water lattice. Suitable thermodynamic conditions and the presence of gas are required for the formation of natural gas hydrates in ocean sediments. Several...
Dinakaran, Srikanth
Liquid-state polaron theory of the hydrated electron revisited
The quantum path integral/classical liquid-state theory of Chandler and co-workers, created to describe an excess electron in solvent, is re-examined for the hydrated electron. The portion that models electron-water density correlations is replaced by two equations: the range optimized random phase approximation (RO-RPA), and the DRL approximation to the "two-chain" equation, both shown previously to describe accurately the static structure and thermodynamics of strongly charged polyelectrolyte solutions. The static equilibrium properties of the hydrated electron are analyzed using five different electron-water pseudopotentials. The theory is then compared with data from mixed quantum/classical Monte Carlo and molecular dynamics simulations using these same pseudopotentials. It is found that the predictions of the RO-RPA and DRL-based polaron theories are similar and improve upon previous theory, with values for almost all properties analyzed in reasonable quantitative agreement with the available simulation data. Also, it is found using the Larsen, Glover and Schwartz pseudopotential that the theories give values for the solvation free energy that are at least three times larger than that from experiment.
James P. Donley; David R. Heine; Caleb A. Tormey; David T. Wu
Hydration of non-polar anti-parallel ?-sheets
In this work we focus on anti-parallel ?-sheets to study hydration of side chains and polar groups of the backbone using all-atom molecular dynamics simulations. We show that: (i) water distribution around the backbone does not depend significantly on amino acid sequence, (ii) more water molecules are found around oxygen than nitrogen atoms of the backbone, and (iii) water molecules around nitrogen are highly localized in the planed formed by peptide backbones. To study hydration around side chains we note that anti-parallel ?-sheets exhibit two types of cross-strand pairing: Hydrogen-Bond (HB) and Non-Hydrogen-Bond (NHB) pairing. We show that distributions of water around alanine, leucine, and valine side chains are very different at HB compared to NHB faces. For alanine pairs, the space between side chains has a higher concentration of water if residues are located in the NHB face of the ?-sheet as opposed to the HB face. For leucine residues, the HB face is found to be dry while the space between side chains at the NHB face alternates between being occupied and non-occupied by water. Surprisingly, for valine residues the NHB face is dry, whereas the HB face is occupied by water. We postulate that these differences in water distribution are related to context dependent propensities observed for ?-sheets.
Urbic, Tomaz [Faculty of Chemistry and Chemical Technology, University of Ljubljana, A�ker?eva 5, SI-1000 Ljubljana (Slovenia)] [Faculty of Chemistry and Chemical Technology, University of Ljubljana, A�ker?eva 5, SI-1000 Ljubljana (Slovenia); Dias, Cristiano L., E-mail: firstname.lastname@example.com [Physics Department, New Jersey Institute of Technology, Newark, New Jersey 07102-1982 (United States)
Dehydration of plutonium or neptunium trichloride hydrate
A process is described for preparing anhydrous actinide metal trichlorides of plutonium or neptunium by reacting an aqueous solution of an actinide metal trichloride selected from the group consisting of plutonium trichloride or neptunium trichloride with a reducing agent capable of converting the actinide metal from an oxidation state of +4 to +3 in a resultant solution, evaporating essentially all the solvent from the resultant solution to yield an actinide trichloride hydrate material, dehydrating the actinide trichloride hydrate material by heating the material in admixture with excess thionyl chloride, and recovering anhydrous actinide trichloride.
Foropoulos, J. Jr.; Avens, L.R.; Trujillo, E.A.
Metal halogen battery construction with improved technique for producing halogen hydrate
An improved electrical energy storage system comprising, at least one cell having a positive electrode and a negative electrode separated by aqueous electrolyte, a store means wherein halogen hydrate is formed and stored as part of an aqueous material having a liquid level near the upper part of the store, means for circulating electrolyte through the cell, conduit means for transmitting halogen gas formed in the cell to a hydrate forming apparatus associated with the store, said hydrate forming apparatus including, a pump to which there is introduced quantities of the halogen gas and chilled water, said pump being located in the store and an outlet conduit leading from the pump and being substantially straight and generally vertically disposed and having an exit discharge into the gas space above the liquid level in the store, and wherein said hydrate forming apparatus is highly efficient and very resistant to plugging or jamming. The disclosure also relates to an improved method for producing chlorine hydrate in zinc chlorine batteries.
Fong, Walter L. (Royal Oak, MI); Catherino, Henry A. (Rochester, MI); Kotch, Richard J. (Mt. Clemens, MI)
In-situ early-age hydration study of sulfobelite cements by synchrotron powder diffraction
Eco-friendly belite calcium sulfoaluminate (BCSA) cement hydration behavior is not yet well understood. Here, we report an in-situ synchrotron X-ray powder diffraction study for the first hours of hydration of BCSA cements. Rietveld quantitative phase analysis has been used to establish the degree of reaction (?). The hydration of a mixture of ye'elimite and gypsum revealed that ettringite formation (? ? 70% at 50 h) is limited by ye'elimite dissolution. Two laboratory-prepared BCSA cements were also studied: non-active-BCSA and active-BCSA cements, with ?- and ??{sub H}-belite as main phases, respectively. Ye'elimite, in the non-active-BCSA system, dissolves at higher pace (? ? 25% at 1 h) than in the active-BCSA one (? ? 10% at 1 h), with differences in the crystallization of ettringite (? ? 30% and ? ? 5%, respectively). This behavior has strongly affected subsequent belite and ferrite reactivities, yielding stratlingite and other layered phases in non-active-BCSA. The dissolution and crystallization processes are reported and discussed in detail. -- Highlights: �Belite calcium sulfoaluminate cements early hydration mechanism has been determined. �Belite hydration strongly depends on availability of aluminum hydroxide. �Orthorhombic ye�elimite dissolved at a higher pace than cubic one. �Ye�elimite larger reaction degree yields stratlingite formation by belite reaction. �Rietveld method quantified gypsum, anhydrite and bassanite dissolution rates.
�lvarez-Pinazo, G.; Cuesta, A.; Garc�a-Mat�, M.; Santacruz, I.; Losilla, E.R. [Departamento de Qu�mica Inorg�nica, Universidad de M�laga, Campus Teatinos S/N., 29071 M�laga (Spain)] [Departamento de Qu�mica Inorg�nica, Universidad de M�laga, Campus Teatinos S/N., 29071 M�laga (Spain); Sanf�lix, S.G. [Unidad T�cnica de Investigaci�n de Materiales, AIDICO, Avda. Benjam�n Franklin, 17 Paterna, Valencia (Spain)] [Unidad T�cnica de Investigaci�n de Materiales, AIDICO, Avda. Benjam�n Franklin, 17 Paterna, Valencia (Spain); Fauth, F. [CELLS-Alba synchrotron, Carretera BP 1413, Km. 3.3, E-08290 Cerdanyola, Barcelona (Spain)] [CELLS-Alba synchrotron, Carretera BP 1413, Km. 3.3, E-08290 Cerdanyola, Barcelona (Spain); Aranda, M.A.G. [Departamento de Qu�mica Inorg�nica, Universidad de M�laga, Campus Teatinos S/N., 29071 M�laga (Spain) [Departamento de Qu�mica Inorg�nica, Universidad de M�laga, Campus Teatinos S/N., 29071 M�laga (Spain); CELLS-Alba synchrotron, Carretera BP 1413, Km. 3.3, E-08290 Cerdanyola, Barcelona (Spain); De la Torre, A.G., E-mail: email@example.com [Departamento de Qu�mica Inorg�nica, Universidad de M�laga, Campus Teatinos S/N., 29071 M�laga (Spain)
Quantum tomography meets dynamical systems and bifurcations theory
A powerful tool for studying geometrical problems in Hilbert spaces is developed. We demonstrate the convergence and robustness of our method in every dimension by considering dynamical systems theory. This method provides numerical solutions to hard problems involving many coupled nonlinear equations in low and high dimensions (e.g., quantum tomography problem, existence and classification of Pauli partners, mutually unbiased bases, complex Hadamard matrices, equiangular tight frames, etc.). Additionally, this tool can be used to find analytical solutions and also to implicitly prove the existence of solutions. Here, we develop the theory for the quantum pure state tomography problem in finite dimensions but this approach is straightforwardly extended to the rest of the problems. We prove that solutions are always attractive fixed points of a nonlinear operator explicitly given. As an application, we show that the statistics collected from three random orthonormal bases is enough to reconstruct pure states from experimental (noisy) data in every dimension d ? 32.
Goyeneche, D., E-mail: email@example.com [Departamento de Fis�ca, Universidad de Concepci�n, Casilla 160-C, Concepci�n, Chile and Center for Optics and Photonics, Universidad de Concepci�n, Casilla 4012, Concepci�n (Chile); Torre, A. C. de la [Departamento de F�sica, Universidad Nacional de Mar del Plata, IFIMAR-CONICET, Dean Funes 3350, 7600 Mar del Plata (Argentina)
Exploring dynamics of unstable many-body systems
In this work we acquaint reader with the Continuum Shell Model (CSM), which is a proper theoretical tool for the description of physics of unstable systems. We describe the effective non-Hermitian Hamiltonian of the CSM and concentrate on specific aspects of dynamics using realistic examples. The continuum effects are discussed in the case of weakly bound heavy oxygen isotopes, where inclusion of continuum coupling is necessary to improve the traditional nuclear shell model techniques. Physics of overlapping resonances is illustrated using recent experimental information on {sup 8}B nucleus. In the limit of strong continuum coupling the many-body states restructure relative to continuum leading to a few very broad super-radiant states, while at the same time other states become narrow and nearly decoupled from decay. The recent observations of very broad alpha clustering states in {sup 18}O is one of the most transparent manifestations of super-radiance.
Volya, Alexander [Department of Physics, Florida State University, Tallahassee, FL 32306-4350 (United States); Zelevinsky, Vladimir [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824-1321 (United States)
Quantum Dynamical Behaviour in Complex Systems - A Semiclassical Approach
One of the biggest challenges in Chemical Dynamics is describing the behavior of complex systems accurately. Classical MD simulations have evolved to a point where calculations involving thousands of atoms are routinely carried out. Capturing coherence, tunneling and other such quantum effects for these systems, however, has proven considerably harder. Semiclassical methods such as the Initial Value Representation (SC-IVR) provide a practical way to include quantum effects while still utilizing only classical trajectory information. For smaller systems, this method has been proven to be most effective, encouraging the hope that it can be extended to deal with a large number of degrees of freedom. Several variations upon the original idea of the SCIVR have been developed to help make these larger calculations more tractable; these range from the simplest, classical limit form, the Linearized IVR (LSC-IVR) to the quantum limit form, the Exact Forward-Backward version (EFB-IVR). In this thesis a method to tune between these limits is described which allows us to choose exactly which degrees of freedom we wish to treat in a more quantum mechanical fashion and to what extent. This formulation is called the Tuning IVR (TIVR). We further describe methodology being developed to evaluate the prefactor term that appears in the IVR formalism. The regular prefactor is composed of the Monodromy matrices (jacobians of the transformation from initial to finial coordinates and momenta) which are time evolved using the Hessian. Standard MD simulations require the potential surfaces and their gradients, but very rarely is there any information on the second derivative. We would like to be able to carry out the SC-IVR calculation without this information too. With this in mind a finite difference scheme to obtain the Hessian on-the-fly is proposed. Wealso apply the IVR formalism to a few problems of current interest. A method to obtain energy eigenvalues accurately for complex systems is described. We proposed the use of a semiclassical correction term to a preliminary quantum calculation using, for instance, a variational approach. This allows us to increase the accuracy significantly. Modeling Nonadiabatic dynamics has always been a challenge to classical simulations because the multi-state nature of the dynamics cannot be described accurately by the time evolution on a single average surface, as is the classical approach. We show that using the Meyer-Miller-Stock-Thoss (MMST) representation of the exact vibronic Hamiltonian in combination with the IVR allows us to accurately describe dynamics where the non Born-Oppenheimer regime. One final problem that we address is that of extending this method to the long time regime. We propose the use of a time independent sampling function in the Monte Carlo integration over the phase space of initial trajectory conditions. This allows us to better choose the regions of importance at the various points in time; by using more trajectories in the important regions, we show that the integration can be converged much easier. An algorithm based loosely on the methods of Diffusion Monte Carlo is developed that allows us to carry out this time dependent sampling in a most efficient manner.
Gliebe, Cheryn E; Ananth, Nandini
Structure-dynamics relationship in coherent transport through disordered systems
Quantum transport is strongly influenced by interference with phase relations that depend sensitively on the scattering medium. Since even small changes in the geometry of the medium can turn constructive interference to destructive, a clear relation between structure and fast, efficient transport is difficult to identify. Here we present a complex network analysis of quantum transport through disordered systems to elucidate the relationship between transport efficiency and structural organization. Evidence is provided for the emergence of structural classes with different geometries but similar high efficiency. Specifically, a structural motif characterised by pair sites which are not actively participating to the dynamics renders transport properties robust against perturbations. Our results pave the way for a systematic rationalization of the design principles behind highly efficient transport which is of paramount importance for technological applications as well as to address transport robustness in natural light harvesting complexes.
Stefano Mostarda; Federico Levi; Diego Prada-Gracia; Florian Mintert; Francesco Rao
Power-system dynamic equivalents:coherency recognition via the rate of change of
.F.I.M.A. Indexing terms: Power systems and plant, Simulation, Time-varying parameters, Dynamic equivalents AbstractPower-system dynamic equivalents:coherency recognition via the rate of change of kinetic energy H of sections of a power system, its main drawback being the extensive computation times required to recognise
Catholic University of Chile (Universidad Católica de Chile)
Impact of Dynamic PHEVs Load on Renewable Sources based Distribution System
Impact of Dynamic PHEVs Load on Renewable Sources based Distribution System F. R. Islam, H. R. email@example.com Abstract--In this paper, charging effect of dynamic Plug in Hybrid Electric Vehicle (PHEV) is presented in a renewable energy based electricity distribution system. For planning and designing a distribution system
Pota, Himanshu Roy
Dynamic evidential networks in system reliability analysis: A Dempster Shafer Approach
Dynamic evidential networks in system reliability analysis: A Dempster Shafer Approach Philippe for modeling and analyzing the system reliability based on Dynamic Evidential Networks (DEN). This method. The current system state determine the probability distribution over the next states. In the work reported
Behavioral interpretation of the object-oriented paradigm for interconnected dynamic system
-oriented language Modelica is finally presented. 1 Keywords Object-modeling techniques, mathematical models, dynamic, published in "International Journal of Systems Science 38, 4 (2007) 319-326" #12;language: Modelica [Tiller dynamic systems, e.g. the language Modelica, lead to handle differential algebraic equation systems
Impact of PHEV Loads on the Dynamic Performance of Power System
additional load to the power systems [5]. According to the Electric Power Research Institute (EPRI), PHEVsImpact of PHEV Loads on the Dynamic Performance of Power System F. R. Islam, H. R. Pota, M. A into the existing grid. This paper analyses the impact of PHEV loads on the dynamic behaviour of a power system
A Dynamical Network View of Lyon's Velo'v Shared Bicycle System
A Dynamical Network View of Lyon's V´elo'v Shared Bicycle System Pierre Borgnat1 , C´eline firstname.lastname@example.com Corresponding Authors Summary. Community shared bicycle systems are an instance of public trans- portation's shared bicycle system, called V´elo'v, can be seen as a dynamical complex network, and how using commu
Robardet, Céline
Comparative Assessment of Advanced Gay Hydrate Production Methods
Displacing natural gas and petroleum with carbon dioxide is a proven technology for producing conventional geologic hydrocarbon reservoirs, and producing additional yields from abandoned or partially produced petroleum reservoirs. Extending this concept to natural gas hydrate production offers the potential to enhance gas hydrate recovery with concomitant permanent geologic sequestration. Numerical simulation was used to assess a suite of carbon dioxide injection techniques for producing gas hydrates from a variety of geologic deposit types. Secondary hydrate formation was found to inhibit contact of the injected CO{sub 2} regardless of injectate phase state, thus diminishing the exchange rate due to pore clogging and hydrate zone bypass of the injected fluids. Additional work is needed to develop methods of artificially introducing high-permeability pathways in gas hydrate zones if injection of CO{sub 2} in either gas, liquid, or micro-emulsion form is to be more effective in enhancing gas hydrate production rates.
M. D. White; B. P. McGrail; S. K. Wurstner
Integrated system dynamics toolbox for water resources planning.
Public mediated resource planning is quickly becoming the norm rather than the exception. Unfortunately, supporting tools are lacking that interactively engage the public in the decision-making process and integrate over the myriad values that influence water policy. In the pages of this report we document the first steps toward developing a specialized decision framework to meet this need; specifically, a modular and generic resource-planning ''toolbox''. The technical challenge lies in the integration of the disparate systems of hydrology, ecology, climate, demographics, economics, policy and law, each of which influence the supply and demand for water. Specifically, these systems, their associated processes, and most importantly the constitutive relations that link them must be identified, abstracted, and quantified. For this reason, the toolbox forms a collection of process modules and constitutive relations that the analyst can ''swap'' in and out to model the physical and social systems unique to their problem. This toolbox with all of its modules is developed within the common computational platform of system dynamics linked to a Geographical Information System (GIS). Development of this resource-planning toolbox represents an important foundational element of the proposed interagency center for Computer Aided Dispute Resolution (CADRe). The Center's mission is to manage water conflict through the application of computer-aided collaborative decision-making methods. The Center will promote the use of decision-support technologies within collaborative stakeholder processes to help stakeholders find common ground and create mutually beneficial water management solutions. The Center will also serve to develop new methods and technologies to help federal, state and local water managers find innovative and balanced solutions to the nation's most vexing water problems. The toolbox is an important step toward achieving the technology development goals of this center.
Reno, Marissa Devan; Passell, Howard David; Malczynski, Leonard A.; Peplinski, William J.; Tidwell, Vincent Carroll; Coursey, Don (University of Chicago, Chicago, IL); Hanson, Jason (University of New Mexico, Albuquerque, NM); Grimsrud, Kristine (University of New Mexico, Albuquerque, NM); Thacher, Jennifer (University of New Mexico, Albuquerque, NM); Broadbent, Craig (University of New Mexico, Albuquerque, NM); Brookshire, David (University of New Mexico, Albuquerque, NM); Chemak, Janie (University of New Mexico, Albuquerque, NM); Cockerill, Kristan (Cockeril Consulting, Boone, NC); Aragon, Carlos (New Mexico Univeristy of Technology and Mining (NM-TECH), Socorro, NM); Hallett, Heather (New Mexico Univeristy of Technology and Mining (NM-TECH), Socorro, NM); Vivoni, Enrique (New Mexico Univeristy of Technology and Mining (NM-TECH), Socorro, NM); Roach, Jesse
Ultrafast Structural Dynamics in Combustion Relevant Model Systems
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
Weber, Peter M. [Brown University
In silico studies of the properties of water hydrating a small protein
Atomistic molecular dynamics simulation of an aqueous solution of the small protein HP-36 has been carried out with explicit solvent at room temperature. Efforts have been made to explore the influence of the protein on the relative packing and ordering of water molecules around its secondary structures, namely, three ?-helices. The calculations reveal that the inhomogeneous water ordering and density distributions around the helices are correlated with their relative hydrophobicity. Importantly, we have identified the existence of a narrow relatively dehydrated region containing randomly organized �quasi-free� water molecules beyond the first layer of �bound� waters at the protein surface. These water molecules with relatively weaker binding energies form the transition state separating the �bound� and �free� water molecules at the interface. Further, increased contribution of solid-like caging motions of water molecules around the protein is found to be responsible for reduced fluidity of the hydration layer. Interestingly, we notice that the hydration layer of helix-3 is more fluidic with relatively higher entropy as compared to the hydration layers of the other two helical segments. Such characteristics of helix-3 hydration layer correlate well with the activity of HP-36, as helix-3 contains the active site of the protein.
Sinha, Sudipta Kumar; Chakraborty, Kausik; Bandyopadhyay, Sanjoy, E-mail: email@example.com [Molecular Modeling Laboratory, Department of Chemistry, Indian Institute of Technology, Kharagpur - 721302 (India); Jana, Madhurima [Molecular Simulation Laboratory, Department of Chemistry, National Institute of Technology, Rourkela - 769008 (India)
Dynamic Scheduling of Hard RealTime Applications in Open System Environment
Dynamic Scheduling of Hard RealTime Applications in Open System Environment Z. Deng J. W.S. Liu J
Fiber Optic Sensing Technology for Detecting Gas Hydrate Formation and Decomposition
A fiber optic-based distributed sensing system (DSS) has been integrated with a large volume (72 L) pressure vessel providing high spatial resolution, time resolved, 3-D measurement of hybrid temperature-strain (TS) values within experimental sediment gas hydrate systems. Areas of gas hydrate formation (exothermic) and decomposition (endothermic) can be characterized through this proxy by time series analysis of discrete data points collected along the length of optical fibers placed within a sediment system. Data is visualized as a 'movie' of TS values along the length of each fiber over time. Experiments conducted in the Seafloor Processing Simulator (SPS) at Oak Ridge National Laboratory show clear indications of hydrate formation and dissociation events at expected P-T conditions given the thermodynamics of the CH4-H2O system. The high spatial resolution achieved with fiber optic technology makes the DSS a useful tool for visualizing time resolved formation and dissociation of gas hydrates in large-scale sediment experiments.
Rawn, Claudia J [ORNL; Leeman, John R [University of Oklahoma, Norman; Ulrich, Shannon M [ORNL; Alford, Jonathan E [ORNL; Phelps, Tommy Joe [ORNL; Madden, Megan Elwood [University of Oklahoma, Norman
Neutron scattering evidence of a boson peak in protein hydration water Alessandro Paciaroni,1
Neutron scattering evidence of a boson peak in protein hydration water Alessandro Paciaroni,1 Anna Viterbo, Italy Received 24 February 1999 Measurement of the low temperature neutron excess of scattering, has been detected by neutron scattering and Raman spectros- copy in a large variety of glassy systems
Tuscia, Università Degli Studi Della
Local Dynamic Reactive Power for Correction of System Voltage Problems
Distribution systems are experiencing outages due to a phenomenon known as local voltage collapse. Local voltage collapse is occurring in part because modern air conditioner compressor motors are much more susceptible to stalling during a voltage dip than older motors. These motors can stall in less than 3 cycles (.05s) when a fault, such as on the sub-transmission system, causes voltage to sag to 70 to 60%. The reasons for this susceptibility are discussed in the report. During the local voltage collapse, voltages are depressed for a period of perhaps one or two minutes. There is a concern that these local events are interacting together over larger areas and may present a challenge to system reliability. An effective method of preventing local voltage collapse is the use of voltage regulation from Distributed Energy Resources (DER) that can supply or absorb reactive power. DER, when properly controlled, can provide a rapid correction to voltage dips and prevent motor stall. This report discusses the phenomenon and causes of local voltage collapse as well as the control methodology we have developed to counter voltage sag. The problem is growing because of the use of low inertia, high efficiency air conditioner (A/C) compressor motors and because the use of electric A/C is growing in use and becoming a larger percentage of system load. A method for local dynamic voltage regulation is discussed which uses reactive power injection or absorption from local DER. This method is independent, rapid, and will not interfere with conventional utility system voltage control. The results of simulations of this method are provided. The method has also been tested at the ORNL s Distributed Energy Communications and Control (DECC) Laboratory using our research inverter and synchronous condenser. These systems at the DECC Lab are interconnected to an actual distribution system, the ORNL distribution system, which is fed from TVA s 161kV sub-transmission backbone. The test results are also provided and discussed. The simulations and testing show that local voltage control from DER can prevent local voltage collapse. The results also show that the control can be provided so quickly, within 0.5 seconds, that is does not interfere with conventional utility methods.
Kueck, John D [ORNL; Rizy, D Tom [ORNL; Li, Fangxing [ORNL; Xu, Yan [ORNL; Li, Huijuan [University of Tennessee, Knoxville (UTK); Adhikari, Sarina [ORNL; Irminger, Philip [ORNL
Universal Science of Complexity: Consistent Understanding of Ecological, Living and Intelligent System Dynamics
A major challenge of interdisciplinary description of complex system behaviour is whether real systems of higher complexity levels can be understood with at least the same degree of objective, "scientific" rigour and universality as "simple" systems of classical, Newtonian science paradigm. The problem is reduced to that of arbitrary, many-body interaction (unsolved in standard theory). Here we review its causally complete solution, the ensuing concept of complexity and applications. The discovered key properties of dynamic multivaluedness and entanglement give rise to a qualitatively new kind of mathematical structure providing the exact version of real system behaviour. The extended mathematics of complexity contains the truly universal definition of dynamic complexity, randomness (chaoticity), classification of all possible dynamic regimes, and the unifying principle of any system dynamics and evolution, the universal symmetry of complexity. Every real system has a non-zero (and actually high) value of unreduced dynamic complexity determining, in particular, "mysterious" behaviour of quantum systems and relativistic effects causally explained now as unified manifestations of complex interaction dynamics. The observed differences between various systems are due to different regimes and levels of their unreduced dynamic complexity. We outline applications of universal concept of dynamic complexity emphasising cases of "truly complex" systems from higher complexity levels (ecological and living systems, brain operation, intelligence and consciousness, autonomic information and communication systems) and show that the urgently needed progress in social and intellectual structure of civilisation inevitably involves qualitative transition to unreduced complexity understanding (we call it "revolution of complexity").
Andrei P. Kirilyuk
DHARMA: A Tool for Evaluating Dynamic Scheduling Algorithms for Realtime Multiprocessor Systems
tolerance and resource reclaiming. Section 3 reviews the earlier work on dynamic scheduling algorithms. In Section 4, we discuss our dynamic scheduling and reclaiming algorithms. Section 5 discusses the software architectureDHARMA: A Tool for Evaluating Dynamic Scheduling Algorithms for Realtime Multiprocessor Systems G
Manimaran, Govindarasu
Dynamics and control of the system of a 2-D rigid circular cylinder and point vortices
Dynamics and control of the system of a 2-D rigid circular cylinder and point vortices Zhanhua Ma dynamically interacting with N point vortices in its vicinity [16] is an idealized example of coupled solid from a fluid mechanics viewpoint as well as a dynamics and control viewpoint. The problem has many
Shashikanth, Banavara N.
Thwarting systems and institutional dynamics, or how to stabilize an unstable economy.
Thwarting systems and institutional dynamics, or how to stabilize an unstable economy. Eric Nasica contained in Minsky's approach, namely that the economy is subject to "financial dynamics", insofar of institutional mechanisms and of the interventions of public authorities on the dynamics of market economies
Ultrafast dynamics of strongly coupled quantum dot-nanocavity systems
We investigate the influence of exciton-phonon coupling on the dynamics of a strongly coupled quantum dot-photonic crystal cavity system and explore the effects of this interaction on different schemes for non-classical light generation. By performing time-resolved measurements, we map out the detuning-dependent polariton lifetime and extract the spectrum of the polariton-to-phonon coupling. Photon-blockade experiments are presented for different pulse-length and detuning conditions that are in very good agreement with quantum-optical simulations; we demonstrate that achieving high-fidelity photon blockade requires an intricate understanding of this parameter space. Furthermore, we show that detuned photon blockade, which is more efficient than resonant photon blockade, is also more dramatically affected by phonons. Finally, we achieve coherent control of the polariton states of a strongly coupled system and demonstrate that their efficient coupling to phonons can be exploited for novel concepts in high-fidelity single photon generation.
Kai M�ller; Kevin A. Fischer; Armand Rundquist; Constantin Dory; Konstantinos G. Lagoudakis; Tomas Sarmiento; Victoria Borish; Yousif A. Kelaita; Jelena Vu?kovi?
Regular and Chaotic Dynamics of Triaxial Stellar Systems
We use Laskar's frequency mapping technique to study the dynamics of triaxial galaxies with central density cusps and nuclear black holes. For ensembles of 10^4 orbits, we numerically compute the three fundamental frequencies of the motion, allowing us to map out the Arnold web. We also compute diffusion rates of stochastic orbits in frequency space. The objects of fundamental importance in structuring phase space are found to be the 3-dimensional resonant tori; even when stable, such tori are not necessarily associated with periodic orbits as in systems with only two degrees of freedom. Boxlike orbits are generically stochastic, but some tube orbits are stochastic as well. The spectrum of diffusion rates for box-like orbits at a given energy is well approximated as a power law over at least six decades. Models with high central concentrations -- steep central cusps or massive black holes -- exhibit the most stochasticity. A black hole with a mass of 0.3% the mass of the galaxy is as effective as the steepest central density cusp at inducing stochastic diffusion. There is a transition to global stochasticity in box-like phase space when the mass of a central black hole exceeds 2% the galaxy mass. We predict a greater average degree of dynamical evolution in faint ellipticals, due to their high central densities and short crossing times. The evolution time is estimated to be shorter than a galaxy lifetime for absolute magnitudes fainter than about -19 or -20, consistent with the observed change in many elliptical galaxy properties at this luminosity.
Monica Valluri; David Merritt
Ab initio study of the structure and dynamics of solvated highly charged metal ions
Study of the Structure and Dynamics of Solvated Highly27 Chapter 3 Structure and Dynamics of the High Spin Fe 3+66 Chapter 4 Structure and Dynamics of the Hydrated Ca 2+
Bogatko, Stuart A.
Coalbed Methane Procduced Water Treatment Using Gas Hydrate Formation at the Wellhead
Water associated with coalbed methane (CBM) production is a significant and costly process waste stream, and economic treatment and/or disposal of this water is often the key to successful and profitable CBM development. In the past decade, advances have been made in the treatment of CBM produced water. However, produced water generally must be transported in some fashion to a centralized treatment and/or disposal facility. The cost of transporting this water, whether through the development of a water distribution system or by truck, is often greater than the cost of treatment or disposal. To address this economic issue, BC Technologies (BCT), in collaboration with Oak Ridge National Laboratory (ORNL) and International Petroleum Environmental Consortium (IPEC), proposed developing a mechanical unit that could be used to treat CBM produced water by forming gas hydrates at the wellhead. This process involves creating a gas hydrate, washing it and then disassociating hydrate into water and gas molecules. The application of this technology results in three process streams: purified water, brine, and gas. The purified water can be discharged or reused for a variety of beneficial purposes and the smaller brine can be disposed of using conventional strategies. The overall objectives of this research are to develop a new treatment method for produced water where it could be purified directly at the wellhead, to determine the effectiveness of hydrate formation for the treatment of produced water with proof of concept laboratory experiments, to design a prototype-scale injector and test it in the laboratory under realistic wellhead conditions, and to demonstrate the technology under field conditions. By treating the water on-site, producers could substantially reduce their surface handling costs and economically remove impurities to a quality that would support beneficial use. Batch bench-scale experiments of the hydrate formation process and research conducted at ORNL confirmed the feasibility of the process. However, researchers at BCT were unable to develop equipment suitable for continuous operation and demonstration of the process in the field was not attempted. The significant achievements of the research area: Bench-scale batch results using carbon dioxide indicate >40% of the feed water to the hydrate formation reactor was converted to hydrate in a single pass; The batch results also indicate >23% of the feed water to the hydrate formation reactor (>50% of the hydrate formed) was converted to purified water of a quality suitable for discharge; Continuous discharge and collection of hydrates was achieved at atmospheric pressure. Continuous hydrate formation and collection at atmospheric conditions was the most significant achievement and preliminary economics indicate that if the unit could be made operable, it is potentially economic. However, the inability to continuously separate the hydrate melt fraction left the concept not ready for field demonstration and the project was terminated after Phase Two research.
BC Technologies
New methods for estimation, modeling and validation of dynamical systems using automatic differentiation
equations, for a class of nonlinear dynamical systems. In the area of trajectory optimization some new ideas are presented for automating the process of deriving co- state differential equations. Additionally, higher-order algorithms for computing... midcourse corrections are introduced. In Chapter IV, some new insights into modeling of dynamical systems are presented. Producing dynamical models in the form of coupled nonlinear differential equations is a frequent first step for analysis, estimation...
Griffith, Daniel Todd
Comparison of Kinetic and Equilibrium Reaction Models in Simulating the Behavior of Gas Hydrates in Porous Media
rate constant of methane gas hydrate decomposition, CanadianAdvances in the Study of Gas Hydrates, C. Taylor , J. Qwan,International Conference on Gas Hydrates, Trondheim, Norway,
Kowalsky, Michael B.; Moridis, George J.
Evaluation of the Gas Production Potential of Marine Hydrate Deposits in the Ulleung Basin of the Korean East Sea
indicators for natural gas hydrates in shallow sediments ofInternational Symposium on Gas Hydrate Technology, Seoul,International Symposium on Gas Hydrate Technology, Seoul,
Moridis, George J.; Reagan, Matthew T.; Kim, Se-Joon; Seol, Yongkoo; Zhang, Keni
Coupled multiphase fluid flow and wellbore stability analysis associated with gas production from oceanic hydrate-bearing sediments
Toward Production from Gas Hydrates: Current Status,Facing Gas Production From Gas-Hydrate Deposits. Society ofConference on Gas Hydrates (ICGH 2011), Edinburgh, Scotland,
Rutqvist, J.
X-ray computed-tomography observations of water flow through anisotropic methane hydrate-bearing sand
Formation of natural gas hydrates in marine sediments 1.Conceptual model of gas hydrate growth conditioned by hostPotential effects of gas hydrate on human welfare, Proc.
Seol, Yongkoo
Numerical studies of gas production from several CH4-hydrate zones at the Mallik Site, Mackenzie Delta, Canada
JNOC/GSC Mallik 2L-38 Gas Hydrate Research Well, Mackenziepermafrost- associated gas hydrate accumulation in theTerritories, Canada. A gas hydrate research well was drilled
Moridis, George J.; Collett, Timothy S.; Dallimore, Scott R.; Satoh, Tohru; Hancock, Steven; Weatherill, Brian
Methane Hydrate Field Studies | Department of Energy
Energy Savers [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 on Delicious RankCombustion |EnergyonSupport0.pdf5 OPAM SEMIANNUAL REPORTMAMay 20Field Studies Methane Hydrate Field
Methane Hydrate Production Feasibility | Department of Energy
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 on Delicious RankCombustion |EnergyonSupport0.pdf5 OPAM SEMIANNUAL REPORTMAMay 20Field Studies Methane Hydrate
Modeling the resource consumption of Housing in New Orleans using System Dynamics
This work uses Systems Dynamics as a methodology to analyze the resource requirements of New Orleans as it recovers from Hurricane Katrina. It examines the behavior of the city as a system of stocks, flows and time delays ...
Quinn, David James, Ph. D. Massachusetts Institute of Technology
Model-Based Methodology for Building Confidence in a Dynamic Measuring System
This thesis examines the special case in which a newly developed dynamic measurement system must be characterized when an accepted standard qualification procedure does not yet exist. In order to characterize this type of system, both physical...
Reese, Isaac Mark
The comparison of four dynamic systems-based software packages: Translation and sensitivity analysis
The comparison of four dynamic systems-based software packages: Translation and sensitivity Wetness Energy Balance (SWEB) model for canopy surface wetness has been translated into four software pack of the model. �? 2005 Elsevier Ltd. All rights reserved. Keywords: Model comparison; Dynamic simulation; System
Vermont, University of
Operator renewal theory and mixing rates for dynamical systems with infinite measure
Operator renewal theory and mixing rates for dynamical systems with infinite measure Ian Melbourne renewal sequences in the context of infinite ergodic theory. For large classes of dynamical systems technique, operator renewal theory, to obtain precise asymptotics and hence sharp mixing rates
Structure and dynamics affect the controllability of complex systems: a Preliminary Study
well does network structure represent the multivariate dynamics of the underlying complex sys- tem- linear multivariate systems. Their organization and behavior are commonly modeled by representations the structure or or- ganization of complex systems. The simplest way to study multi-variate dynamics
Dynamic behaviour of a DFIG wind turbine subjected to power system faults
of the dynamic interaction between variable speed DFIG wind turbines and the power system subjected by the Danish Transmission System Operator Energinet.dk. Keywords: doubly-fed induction generator (DFIG), wind turbines, the variable speed DFIG wind turbine with its dynamic behaviour and its ride-through capabil- ity
Energy Aware Dynamic Voltage and Frequency Selection for Real-Time Systems with Energy Harvesting
Energy Aware Dynamic Voltage and Frequency Selection for Real-Time Systems with Energy firstname.lastname@example.com Abstract In this paper, an energy aware dynamic voltage and frequency selection (EA-DVFS) algorithm energy and the harvested energy in a future duration. Specifically, if the system has sufficient energy
Qiu, Qinru
Land-use transport systems: Comparing local policy dynamics in Swiss and French urban areas
Land-use transport systems: Comparing local policy dynamics in Swiss and French urban areas GALLEZ LAND-USE TRANSPORT SYSTEMS: COMPARING LOCAL POLICY DYNAMICS IN SWISS AND FRENCH URBAN AREAS GALLEZ, there is a broad consensus among researchers and transport/urban planning professionals that more coherence
Dynamic Code Overlay of SDF-Modeled Programs on Low-end Embedded Systems
Dynamic Code Overlay of SDF-Modeled Programs on Low-end Embedded Systems Hae-woo Park Kyoungjoo Oh of synchronous data-flow (SDF) modeled program for low-end embedded systems which lack MMU- support-program code, dynamic loader and linker script files from the given SDF- modeled blocks and schematic, so we
Ha, Soonhoi
On the dynamics of lattice systems with unbounded on-site terms in the Hamiltonian
We supply the mathematical arguments required to complete the proofs of two previously published results: Lieb-Robinson bounds for the dynamics of quantum lattice systems with unbounded on-site terms in the Hamiltonian and the existence of the thermodynamic limit of the dynamics of such systems.
Bruno Nachtergaele; Robert Sims
Towards a General Theory of Extremes for Observables of Chaotic Dynamical Systems Valerio Lucarini,
Towards a General Theory of Extremes for Observables of Chaotic Dynamical Systems Valerio Lucarini the geometrical properties of a chaotic dynamical system and the distribution of extreme values. We show that the extremes of so-called physical observables are distributed according to the classical generalised Pareto
International Conference on Gas Hydrates May 19-23, 2002, Yokohama
4th International Conference on Gas Hydrates May 19-23, 2002, Yokohama Cold Flow Hydrate Technology an opportunity for flow assurance in deepwater production of oil and gas. Hydrate R&D in the Natural Gas Hydrate exchange and reactor units. Introduction Hydrates form when liquid water and natural gas are in contact
Gudmundsson, Jon Steinar
Phase space theory of quantum�classical systems with nonlinear and stochastic dynamics
A novel theory of hybrid quantum�classical systems is developed, utilizing the mathematical framework of constrained dynamical systems on the quantum�classical phase space. Both, the quantum and classical descriptions of the respective parts of the hybrid system are treated as fundamental. Therefore, the description of the quantum�classical interaction has to be postulated, and includes the effects of neglected degrees of freedom. Dynamical law of the theory is given in terms of nonlinear stochastic differential equations with Hamiltonian and gradient terms. The theory provides a successful dynamical description of the collapse during quantum measurement. -- Highlights: �A novel theory of quantum�classical systems is developed. �Framework of quantum constrained dynamical systems is used. �A dynamical description of the measurement induced collapse is obtained.
Buri?, Nikola, E-mail: email@example.com; Popovi?, Du�ka B.; Radonji?, Milan; Prvanovi?, Slobodan
Integrated dynamic landscape analysis and modeling system (IDLAMS) : installation manual.
The Integrated Dynamic Landscape Analysis and Modeling System (IDLAMS) is a prototype, integrated land management technology developed through a joint effort between Argonne National Laboratory (ANL) and the US Army Corps of Engineers Construction Engineering Research Laboratories (USACERL). Dr. Ronald C. Sundell, Ms. Pamela J. Sydelko, and Ms. Kimberly A. Majerus were the principal investigators (PIs) for this project. Dr. Zhian Li was the primary software developer. Dr. Jeffrey M. Keisler, Mr. Christopher M. Klaus, and Mr. Michael C. Vogt developed the decision analysis component of this project. It was developed with funding support from the Strategic Environmental Research and Development Program (SERDP), a land/environmental stewardship research program with participation from the US Department of Defense (DoD), the US Department of Energy (DOE), and the US Environmental Protection Agency (EPA). IDLAMS predicts land conditions (e.g., vegetation, wildlife habitats, and erosion status) by simulating changes in military land ecosystems for given training intensities and land management practices. It can be used by military land managers to help predict the future ecological condition for a given land use based on land management scenarios of various levels of training intensity. It also can be used as a tool to help land managers compare different land management practices and further determine a set of land management activities and prescriptions that best suit the needs of a specific military installation.
Li, Z.; Majerus, K. A.; Sundell, R. C.; Sydelko, P. J.; Vogt, M. C.
Integrated dynamic landscape analysis and modeling system (IDLAMS) : programmer's manual.
Klaus, C. M.; Li, Z.; Majerus, K. A.; Sundell, R. C.; Sydelko, P. J.; Vogt, M. C.
Marine Protists : : Distributions, Diversity and Dynamics
and sulfide flux at gas hydrate deposits from the Cascadiaoxidation of methane above gas hydrates at Hydrate Ridge, NEoxidation of methane above gas hydrate at Hydrate Ridge, NE
Pasulka, Alexis Leah
Development of Alaskan gas hydrate resources. Final report
Natural gas hydrates - issues for gas production and geomechanical stability
occurring at the field. Further, the controlling parameters for hydrate dissociation in porous media are quantified and a sensitivity study is presented. Chapter VI presents the results of a simulation experiment done to evaluate the performance of a..., the location iv of perforations and the gas hydrate saturation to be important parameters for gas production at the Messoyakha. Second, I simulated the gas production using a hydraulic fracture in hydrate bearing sediments. The simulation results showed...
Grover, Tarun
Structure and Dynamics of Biological Systems Research Team: James E. Evans, Daniel E. Perea, Xiao-Ying Yu, Zihua Zhu
Structure and Dynamics of Biological Systems Research Team: James E. Evans, Daniel E. Perea, Xiao for atomic resolution structure determination; observe dynamics using a pump-probe regime. Dynamic TEM probe tomography to interrogate the structure and dynamics of biological systems
angiogenesis vascularity hydration: Topics by E-print Network
I. Introduction Cementpaste,the binding phaseof concrete Bentz, Dale P. 177 NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration Engineering Websites Summary: NISTIR...
aluminum hydration effects: Topics by E-print Network
I. Introduction Cementpaste,the binding phaseof concrete Bentz, Dale P. 258 NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration Engineering Websites Summary: NISTIR...
Energy Department Expands Research into Methane Hydrates, a Vast...
separate project funded by the EU through Universities of Bremen (Germany) and Tromso (Norway), will assess the response of methane hydrates to environmental changes at the...
Geomechanical Performance of Hydrate-Bearing Sediment in Offshore Environments
The objective of this multi-year, multi-institutional research project was to develop the knowledge base and quantitative predictive capability for the description of geomechanical performance of hydrate-bearing sediments (hereafter referred to as HBS) in oceanic environments. The focus was on the determination of the envelope of hydrate stability under conditions typical of those related to the construction and operation of offshore platforms. We have developed a robust numerical simulator of hydrate behavior in geologic media by coupling a reservoir model with a commercial geomechanical code. We also investigated the geomechanical behavior of oceanic HBS using pore-scale models (conceptual and mathematical) of fluid flow, stress analysis, and damage propagation. The objective of the UC Berkeley work was to develop a grain-scale model of hydrate-bearing sediments. Hydrate dissociation alters the strength of HBS. In particular, transformation of hydrate clusters into gas and liquid water weakens the skeleton and, simultaneously, reduces the effective stress by increasing the pore pressure. The large-scale objective of the study is evaluation of geomechanical stability of offshore oil and gas production infrastructure. At Lawrence Berkeley National Laboratory (LBNL), we have developed the numerical model TOUGH + Hydrate + FLAC3D to evaluate how the formation and disassociation of hydrates in seafloor sediments affects seafloor stability. Several technical papers were published using results from this model. LBNL also developed laboratory equipment and methods to produce realistic laboratory samples of sediments containing gas hydrates so that mechanical properties could be measured in the laboratory. These properties are required to run TOUGH + Hydrate + FLAC3D to evaluate seafloor stability issues. At Texas A&M University we performed a detailed literature review to determine what gas hydrate formation properties had been measured and reported in the literature. We then used TOUGH + Hydrate to simulate the observed gas production and reservoir pressure field data at Messoyakha. We simulated various scenarios that help to explain the field behavior. We have evaluated the effect of reservoir parameters on gas recovery from hydrates. Our work should be beneficial to others who are investigating how to produce gas from a hydrate capped gas reservoir. The results also can be used to better evaluate the process of producing gas from offshore hydrates. The Schlumberger PETREL model is used in industry to the description of geologic horizons and the special distribution of properties. An interface between FLAC3D and Petrel was built by Schlumberger to allow for efficient data entry into TOUGH + Hydrate + FLAC3D.
Stephen Holditch; Tad Patzek; Jonny Rutqvist; George Moridis; Richard Plumb
Method for the photocatalytic conversion of gas hydrates
A method for converting methane hydrates to methanol, as well as hydrogen, through exposure to light. The process includes conversion of methane hydrates by light where a radical initiator has been added, and may be modified to include the conversion of methane hydrates with light where a photocatalyst doped by a suitable metal and an electron transfer agent to produce methanol and hydrogen. The present invention operates at temperatures below 0.degree. C., and allows for the direct conversion of methane contained within the hydrate in situ.
Taylor, Charles E. (Pittsburg, PA); Noceti, Richard P. (Pittsburg, PA); Bockrath, Bradley C. (Bethel Park, PA)
Contribution of oceanic gas hydrate dissociation to the formation of Arctic Ocean methane plumes
Potential distribution of methane hydrate in the world'sisotopic evidence for methane hydrate instability duringHendy, L.L. , and R.J. Behl, Methane hydrates in quaternary
S.S.H. , 1987. Kinetics of Methane Hydrate Decomposition,T. J. , et al. (2007), Methane Hydrate Formation andCharting the future of methane hydrate research in the
Occurrence of gas hydrate in Oligocene Frio sand: Alaminos Canyon Block 818: Northern Gulf of Mexico
Advances in the Study of Gas Hydrates. Kluwer, New York, pp.and quantification of gas hydrates using rock physics andand Salt Inhibition of Gas Hydrate Formation in the Northern
Boswell, R.D.
Comparison of kinetic and equilibrium reaction models in simulating gas hydrate behavior in porous media
with Diapirism and Gas Hydrates at the Head of the Cape FearSea-Level Low Stands Above Gas Hydrate-Bearing Sediments.rate constant of methane gas hydrate decomposition. Canadian
Estimation of composite thermal conductivity of a heterogeneous methane hydrate sample using iTOUGH2
International Conference on Gas Hydrates, Trondheim, Norway,Challenges for the future/gas hydrates, NYAS 912, 304, 2000.C. , Thermal state of the gas hydrate reservoir, natural gas
Gupta, Arvind; Kneafsey, Timothy J.; Moridis, George J.; Seol, Yongkoo; Kowalsky, Michael B.; Sloan Jr., E.D.
Development of a Numerical Simulator for Analyzing the Geomechanical Performance of Hydrate-Bearing Sediments
J. Mienert. 2004. Effect of gas hydrates melting on seafloorInternational Conference on Gas Hydrates, Trondheim, Norway,A Documented Example of Gas Hydrate Saturated Sand in the
Geomechanical response of permafrost-associated hydrate deposits to depressurization-induced gas production
Conference on Gas Hydrates (ICGH 2008), Vancouver, BritishGSC et al. Mallik 5L-38 gas hydrate production research wellfrom the Mallik 2002 Gas Hydrate Production Research Well
Sensitivity Analysis of Gas Production from Class 2 and Class 3 Hydrate Deposits
a) temperature, (b) gas and hydrate phase saturations, and (A Documented Example of Gas Hydrate Saturated Sand in theMakogon, Y.F. , �Gas hydrates: frozen energy,� Recherche 18(
Reagan, Matthew
The Use of Horizontal Wells in Gas Production from Hydrate Accumulations
E.D. Toward Production From Gas Hydrates: Current Status,International Conference on Gas Hydrates, Trondheim, Norway,for Gas Production from Gas Hydrate Reservoirs, J. Can. Pet.
Moridis, George J.
V.A. Soloviev, Submarine Gas Hydrates. St. Petersburg, 1998.and stability of gas hydrate-related bottom-simulatingPotential effects of gas hydrate on human welfare, Proc.
In situ molecular imaging of hydrated biofilm in a microfluidic reactor by ToF-SIMS
The first results of using a novel single channel microfluidic reactor to enable Shewanella biofilm growth and in situ characterization using time-of-flight secondary ion mass spectrometry (ToF-SIMS) in the hydrated environment are presented. The new microfluidic interface allows direct probing of the liquid surface using ToF-SIMS, a vacuum surface technique. The detection window is an aperture of 2 m in diameter on a thin silicon nitride (SiN) membrane and it allows direct detection of the liquid surface. Surface tension of the liquid flowing inside the microchannel holds the liquid within the aperture. ToF-SIMS depth profiling was used to drill through the SiN membrane and the biofilm grown on the substrate. In situ 2D imaging of the biofilm in hydrated state was acquired, providing spatial distribution of the chemical compounds in the biofilm system. This data was compared with a medium filled microfluidic reactor devoid of biofilm and dried biofilm samples deposited on clean silicon wafers. Principle Component Analysis (PCA) was used to investigate these observations. Our results show that imaging biofilms in the hydrated environment using ToF-SIMS is possible using the unique microfluidic reactor. Moreover, characteristic biofilm fatty acids fragments were observed in the hydrated biofilm grown in the microfluidic channel, illustrating the advantage of imaging biofilm in its native environment.
Hua, Xin; Yu, Xiao-Ying; Wang, Zhaoying; Yang, Li; Liu, Bingwen; Zhu, Zihua; Tucker, Abigail E.; Chrisler, William B.; Hill, Eric A.; Thevuthasan, Suntharampillai; Lin, Yuehe; Liu, Songqin; Marshall, Matthew J.
Methane hydrate distribution from prolonged and repeated formation in natural and compacted sand samples: X-ray CT observations
K. and McDonald, T. , Gas Hydrates of the Middle Americaet al. , Indian National Gas Hydrate Program Expedition 01et al. , Drilling Gas Hydrates on Hydrate Ridge, Cascadia
Rees, E.V.L.
Quantum wave packet ab initio molecular dynamics: An approach to study quantum dynamics in large systems
of computational methods in gas-phase1 and condensed phase quantum dynamics.2 In many cases the Born robust by using adaptive grids to achieve optimized sampling. One notable feature of the approach
Iyengar, Srinivasan S.
Enterprise design for dynamic complexity : architecting & engineering organizations using system & structural dynamics
As the business world is neither linear nor static, the mastery of its "chaotic" nonlinear dynamics lies at the heart of finding high-leverage policies that return uncommon benefits for marginal costs. Today's global ...
Piepenbrock, Theodore F. (Theodore Frederick), 1965-
Human Growth and Body Weight Dynamics: An Integrative Systems Model
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 ...
Rahmandad, Hazhir
Surfactant process for promoting gas hydrate formation and application of the same
This invention relates to a method of storing gas using gas hydrates comprising forming gas hydrates in the presence of a water-surfactant solution that comprises water and surfactant. The addition of minor amounts of surfactant increases the gas hydrate formation rate, increases packing density of the solid hydrate mass and simplifies the formation-storage-decomposition process of gas hydrates. The minor amounts of surfactant also enhance the potential of gas hydrates for industrial storage applications.
Rogers, Rudy E. (Starkville, MS); Zhong, Yu (Brandon, MS)
Macromolecular hydration compared with preferential hydration and their role on macromolecule-osmolyte coupled diffusionwz
to solute hydration and size ratio and is not complicated by other factors such as ionic interactions should not be neglected in multicomponent-diffusion theoretical models even when ionic interactions quantities that shape the thermodynamic and diffusion behavior of macromoleculeadditivewater solutions.1
Annunziata, Onofrio
Electron beam dynamics for the ISIS bremsstrahlung beam generation system
An electron beam transport system was designed for use in the Bremsstrahlung Beam Generation System of the Integrated Stand-off Inspection System (ISIS). The purpose of this electron transport system was to provide for ...
Block, Robert E. (Robert Edward)
SIAM conference on applications of dynamical systems. Abstracts and author index
Metal-Catalyzed Hydration of 2-Pyridyloxirane
-401 CuSO, at 22". The rate of the copper-catalysed hydration is proportional to the copper concentration, and a t low pH the reaction obeys pseudo-first-order kinetics. At high pH the rate decreases as the reaction proceeds, probably because... the product acts as a tridentate chelating agent and removes the copper in a non-catalytic form. Thus the rate law for the reaction in O.~M-KH,PO, (pH 5.09) is: - d[epoxide]/dt= (k, + R,[Cu2+])[epoxide], where A , and Km, the rate con- stants...
Hanzlik, Robert P.; Michaely, William J.
Gas hydrates in the Gulf of Mexico
filled by one or more gases. In marine sediments gas hydrates are found in regions where high pressure, low temperature and gas in excess of solubility are present. Low molecular weight hydrocarbons (LMWH), I. e. methane through butane, carbon dioxide... loop at a helium carrier flow of 12 ml/min with an elution order of methane, ethane, carbon dioxide and propane. Each fraction was trapped in a U- shaped Porpak-Q filled glass tube immersed in LN2. Butanes and heartier weight gases were trapped...
Cox, Henry Benjamin
Methane Hydrate Program Annual Report to Congress
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 on Office of Inspector General Office0-72.pdfGeorgeDoesn't32 Master EM ProjectMemoDepartmentFY 2010 Methane Hydrate
Dynamics of the UK Natural Gas Industry: System Dynamics Modelling and Long-Term Energy Policy Analysis
www.eprg.group.cam.ac.uk E P R G W O R K IN G P A P E R N O N -T E C H N IC A L S U M M A R Y DYNAMICS OF THE UK NATURAL GAS INDUSTRY: SYSTEM DYNAMICS MODELLING AND LONG-TERM ENERGY POLICY ANALYSIS EPRG Working Paper 0913... Cambridge Working Paper in Economics 0922 Kong Chyong Chi , David M. Reiner and William J. Nuttall The UK offshore natural gas and oil industry has a long and successful history and has been said to represent the pride of UK...
Chi, K C; Reiner, David; Nuttall, William J
Calibration of Reduced Dynamic Models of Power Systems using Phasor Measurement Unit (PMU) Data
Accuracy of a power system dynamic model is essential to the secure and efficient operation of the system. Lower confidence on model accuracy usually leads to conservative operation and lowers asset usage. To improve model accuracy, identification algorithms have been developed to calibrate parameters of individual components using measurement data from staged tests. To facilitate online dynamic studies for large power system interconnections, this paper proposes a model reduction and calibration approach using phasor measurement unit (PMU) data. First, a model reduction method is used to reduce the number of dynamic components. Then, a calibration algorithm is developed to estimate parameters of the reduced model. This approach will help to maintain an accurate dynamic model suitable for online dynamic studies. The performance of the proposed method is verified through simulation studies.
Zhou, Ning; Lu, Shuai; Singh, Ruchi; Elizondo, Marcelo A.
A test for a conjecture on the nature of attractors for smooth dynamical systems
Dynamics arising persistently in smooth dynamical systems ranges from regular dynamics (periodic, quasiperiodic) to strongly chaotic dynamics (Anosov, uniformly hyperbolic, nonuniformly hyperbolic modelled by Young towers). The latter include many classical examples such as Lorenz and H�non-like attractors and enjoy strong statistical properties. It is natural to conjecture (or at least hope) that most dynamical systems fall into these two extreme situations. We describe a numerical test for such a conjecture/hope and apply this to the logistic map where the conjecture holds by a theorem of Lyubich, and to the 40-dimensional Lorenz-96 system where there is no rigorous theory. The numerical outcome is almost identical for both (except for the amount of data required) and provides evidence for the validity of the conjecture.
Gottwald, Georg A., E-mail: email@example.com [School of Mathematics and Statistics, University of Sydney, Sydney 2006 NSW (Australia); Melbourne, Ian, E-mail: firstname.lastname@example.com [Mathematics Institute, University of Warwick, Coventry CV4 7AL (United Kingdom)] [Mathematics Institute, University of Warwick, Coventry CV4 7AL (United Kingdom)
Scalable Approach to Uncertainty Quantification and Robust Design of Interconnected Dynamical Systems
Development of robust dynamical systems and networks such as autonomous aircraft systems capable of accomplishing complex missions faces challenges due to the dynamically evolving uncertainties coming from model uncertainties, necessity to operate in a hostile cluttered urban environment, and the distributed and dynamic nature of the communication and computation resources. Model-based robust design is difficult because of the complexity of the hybrid dynamic models including continuous vehicle dynamics, the discrete models of computations and communications, and the size of the problem. We will overview recent advances in methodology and tools to model, analyze, and design robust autonomous aerospace systems operating in uncertain environment, with stress on efficient uncertainty quantification and robust design using the case studies of the mission including model-based target tracking and search, and trajectory planning in uncertain urban environment. To show that the methodology is generally applicable to...
Banaszuk, Andrzej; Frewen, Thomas A; Kobilarov, Marin; Mathew, George; Mezic, Igor; Pinto, Alessandro; Sahai, Tuhin; Sane, Harshad; Speranzon, Alberto; Surana, Amit
E-Print Network 3.0 - alaskan gas hydrate Sample Search Results
and finally the prospects for methane hydrates. NATURAL GAS AND THE RECOVERY PROCESS The primary... Coal Bed Methane Shale Gas Methane Hydrates Volume...
Operator renewal theory and mixing rates for dynamical systems with in nite measure
Operator renewal theory and mixing rates for dynamical systems with in#12;nite measure Ian of operator renewal sequences in the context of in#12;nite ergodic theory. For large classes of dynamical for mixing rates. Sarig [37] introduced a powerful new technique, operator renewal theory, to obtain precise
Multiagent Bayesian Forecasting of Structural Time-Invariant Dynamic Systems with
. Alternatively, time series are represented by state-space models, also referred to as multivariate dynamic and science. We study forecasting of stochastic, dynamic systems based on observations from multivariate time to a discrete time, multivariate time series [1, 2]. The primary inference that we address is one- step
Xiang, Yang
Basins of attraction in quadratic dynamical systems with a Jordan fixed point Marco Abate
Basins of attraction in quadratic dynamical systems with a Jordan fixed point Marco Abate Fax: +39/06/72594699 email: firstname.lastname@example.com Abstract In this note we study the dynamics to the exceptional divisor and thus it can be projected down #12; 2 Marco Abate producing a parabolic curve
Roma Tor Vergata, Università di
8th International IFAC Symposium on Dynamics and Control of Process Systems
-of-freedom, Dynamic, Economic, Plantwide, Optimization. 1. INTRODUCTION Due to globalisation the process industry;According to White (1999) economic process optimization dates back almost 50 years. The current state8th International IFAC Symposium on Dynamics and Control of Process Systems DEGREES OF FREEDOM
Van den Hof, Paul
Microfluidic systems for single DNA dynamics Danielle J. Mai,a
Microfluidic systems for single DNA dynamics Danielle J. Mai,a Christopher Brockmana and Charles M in microfluidics have enabled the molecular-level study of polymer dynamics using single DNA chains. Single polymer. Microfluidic devices have enabled the precise control of model flow fields to study the non
Schroeder, Charles
Integration and Dynamics of a Renewable Regenerative Hydrogen Fuel Cell System
Integration and Dynamics of a Renewable Regenerative Hydrogen Fuel Cell System by Alvin Peter, hydrogen and electricity storage, and fuel cells. A special design feature of this test bed is the ability of the author. #12;ii Supervisory Committee Integration and Dynamics of a Renewable Regenerative Hydrogen Fuel
Victoria, University of
Ice method for production of hydrogen clathrate hydrates
The present invention includes a method for hydrogen clathrate hydrate synthesis. First, ice and hydrogen gas are supplied to a containment volume at a first temperature and a first pressure. Next, the containment volume is pressurized with hydrogen gas to a second higher pressure, where hydrogen clathrate hydrates are formed in the process.
Lokshin, Konstantin (Santa Fe, NM); Zhao, Yusheng (Los Alamos, NM)
Effects of Antiagglomerants on the Interactions between Hydrate Particles
production Introduction The undesirable formation of gas hydrates in natural gas pipelines, and their prevention is a problem that has received considerable interest. In subsea pipelines, the presence of water of hydrates. These crystalline compounds can agglomerate and form plugs in the pipelines. The costs associated
Analysis and synthesis techniques of nonlinear dynamical systems with applications to diagnostic of controlled thermonuclear fusion reactors.
??Nonlinear dynamical systems are of wide interest to engineers, physicists and mathematicians, and this is due to the fact that most of physical systems in� (more)
Pisano, Fabio
Seismic-Scale Rock Physics of Methane Hydrate
We quantify natural methane hydrate reservoirs by generating synthetic seismic traces and comparing them to real seismic data: if the synthetic matches the observed data, then the reservoir properties and conditions used in synthetic modeling might be the same as the actual, in-situ reservoir conditions. This approach is model-based: it uses rock physics equations that link the porosity and mineralogy of the host sediment, pressure, and hydrate saturation, and the resulting elastic-wave velocity and density. One result of such seismic forward modeling is a catalogue of seismic reflections of methane hydrate which can serve as a field guide to hydrate identification from real seismic data. We verify this approach using field data from known hydrate deposits.
Amos Nur
Decoherence Dynamics of Measurement-Induced Nonlocality and comparison with Geometric Discord for two qubit systems
We check the decoherence dynamics of Measurement-induced Nonlocality(in short, MIN) and compare it with geometric discord for two qubit systems. There are quantum states, on which the action of dephasing channel cannot destroy MIN in finite or infinite time. We check the additive dynamics of MIN on a qubit state under two independent noise. Geometric discord also follows such additive dynamics like quantum discord. We have further compared non-Markovian evolution of MIN and geometric discord under dephasing and amplitude damping noise for pure state and it shows distinct differences between their dynamics.
Ajoy Sen; Debasis Sarkar; Amit Bhar
Spatially resolved dynamic structure factor of finite systems from molecular dynamics simulations
The dynamical response of metallic clusters up to 10{sup 3} atoms is investigated using the restricted molecular dynamics simulations scheme. Exemplarily, a sodium like material is considered. Correlation functions are evaluated to investigate the spatial structure of collective electron excitations and the optical response of laser-excited clusters. In particular, the spectrum of bilocal correlation functions shows resonances representing different modes of collective excitations inside the nano plasma. The spatial structure, the resonance energy, and the width of the eigenmodes have been investigated for various values of electron density, temperature, cluster size, and ionization degree. Comparison with bulk properties is performed and the dispersion relation of collective excitations is discussed.
Raitza, Thomas; Roepke, Gerd; Reinholz, Heidi; Morozov, Igor [Institut fuer Physik, Universitaet Rostock, D-18051 Rostock (Germany); Institut fuer Theoretische Physik, Johannes-Kepler-Universitaet Linz, A-4040 Linz, Austria and Institute of Physics, University of Western Australia, Perth, WA 6009 (Australia); Joint Institute for High Temperatures of RAS, 13 Izhorskaya Street, Building 2, Moscow RU-125412 (Russian Federation)
The dynamics of 'systems building' : An analysis of process mutations
This thesis investigates systems building in architecture. As the systems approach is an organized process for problem solving, the understanding of structural and functional relationships is essential. As systems building ...
Paul, Rathindra Jurg
Dynamical systems in nanophotonics: From energy efficient modulators to light forces and optomechanics
We demonstrate novel device concepts based on rigorous design of the dynamics of resonant nanophotonic systems, such as dispersionless resonant switches and energy-efficient mo-dulator architectures, slow-light cells, and ...
Kaertner, Franz X.
Networking technology adoption : system dynamics modeling of fiber-to-the-home
A system dynamics model is developed and run to study the adoption of fiber-to-the-home as a residential broadband technology. Communities that currently do not have broadband in the United States are modeled. This case ...
Kelic, Andjelka, 1972-
Dynamics and real-time optimal control of satellite attitude and satellite formation systems
In this dissertation the solutions of the dynamics and real-time optimal control of magnetic attitude control and formation flying systems are presented. In magnetic attitude control, magnetic actuators for the time-optimal rest-to-rest maneuver...
Yan, Hui
15.874 / 15.871 System Dynamics for Business Policy, Fall 2003
15.874 and 15.871 provide an introduction to system dynamics modeling for the analysis of business policy and strategy. Students learn to visualize a business organization in terms of the structures and policies that create ...
Morrison, J. Bradley
Incorporating endogenous demand dynamics into long-term capacity expansion power system models for Developing countries
This research develops a novel approach to long-term power system capacity expansion planning for developing countries by incorporating endogenous demand dynamics resulting from social processes of technology adoption. ...
Jordan, Rhonda LeNai
The Center for Control, Dynamical Systems, and Computation University of California at Santa Barbara
by an example we will then explore the relationship between security and control systems. Finally we in the areas of systems, communications, control and signal processing at U.C. Berkeley. His research interestsThe Center for Control, Dynamical Systems, and Computation University of California at Santa
Modeling and Dynamic Management of 3D Multicore Systems with Liquid Cooling
in the future to address the increasing power density. Considering the high power densities in 3D systems Mi- crosystems, UC MICRO, Center for Networked Systems (CNS) at UCSD, MARCO/DARPA GSRC and NSFModeling and Dynamic Management of 3D Multicore Systems with Liquid Cooling Ayse K. Coskun , Jos
Simunic, Tajana
Evaluation of lime-fly ash stabilized bases and subgrades using static and dynamic deflection systems
EVALUATION OF LIME-FLY ASH STABILIZED BASFS AND SUBGRADES USING STATIC AND DYNAMIC DEFLECTION SYSTEMS A Thesis GARY W. RABA Submitted to the Graduate College of Texas AIIM University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 1982 Major Subject: Civil Engineering EVALUATION OF LIME-FLY ASH STABILIZED BASES AND SUBGRADES USING STATIC AND DYNAMIC DEFLECTION SYSTEMS A Thesis by Gary Nl. Raba Approved as to style and content by: !Chairman...
Raba, Gary W.
Distributed Dynamics of Systems with Closed Kinematic Chains
) Orin and Walker (1982): Efficient dynamic computer simulation of robotic mechanisms Featherstone block predictor-corrector methods of ODE's Chain-level distribution McMillan, Sadayappan and Orin Two NASA robots carrying a metal beam (a) (b) Figure 2.10: ARNOLD, MDOF vehicle with compliant linkage
Krovi, Venkat
Nonlinear Temporal Dynamics of Strongly Coupled Quantum Dot-Cavity System
We theoretically analyze and simulate the temporal dynamics of strongly coupled quantum dot-cavity system driven by a resonant laser pulse. We observe the signature of Rabi oscillation in the time resolved response of the system (i.e., in the numerically calculated cavity output), derive simplified linear and non-linear semi-classical models that approximate well the system's behavior in the limits of high and low power drive pulse, and describe the role of quantum coherence in the exact dynamics of the system. Finally, we also present experimental data showing the signature of the Rabi oscillation in time domain.
Arka Majumdar; Dirk Englund; Michal Bajcsy; Jelena Vuckovic
A new dynamical indicator for chaos detection in galactic Hamiltonian systems
A new dynamical parameter, the f-indicator, is introduced and used in order to distinguish between regular and chaotic motion in galactic Hamiltonian systems. Two kinds of galactic potentials are used: (i) a global potential, which describes the whole galaxy and (ii) a local potential, which is made up of perturbed harmonic oscillators and describes motion near an equilibrium point. The new indicator is based on the energies of the separable system along the x, y and z axis. Comparison between the outcomes obtained using the new dynamical parameter and other methods, such as the maximum Lyapunov Characteristic Exponent (L.C.E), or the S(c) dynamical spectrum, shows that the new dynamical indicator gives fast and reliable results concerning the regular or chaotic character of the orbits. The new indicator was tested in several Hamiltonian systems of two (2D) degrees and three (3D) degrees of freedom.
Euaggelos E. Zotos
Biosystem Dynamics & Design | EMSL
Biosystem Dynamics & Design Overview Atmospheric Aerosol Systems Biosystem Dynamics & Design Energy Materials & Processes Terrestrial & Subsurface Ecosystems Biosystem Dynamics &...
Dynamic Control of Serial-batch Processing Systems
measures are selected over other possible measures due to their prevalent use by semiconductor manufacturing management as production performance indicators in the long-run (month/quarter) (Pfund et al. (2006)). The research domain... of incompatible product types and different batch process times. The static problem has been shown NP-hard for total completion time (Chandru et al. (1993a)), makespan (Uzsoy (1994)) and total tardiness (Mehta and Uzsoy (1998)) criteria. The dynamic problem has...
Cerekci, Abdullah
The dynamics and kinematics of bio-in swimming systems
The motion of biological systems in fluids is inherently complex, even for the simplest organisms. In this thesis, we develop methods of analyzing locomotion of both mechanical and biological systems with the aim of ...
Burton, Lisa Janelle
Diversity in evolving systems : scaling and dynamics of genealogical trees
Diversity is a fundamental property of all evolving systems. This thesis examines spatial and temporal patterns of diversity. The systems I will study consist of a population of individuals, each with a potentially unique ...
Rauch, Erik, 1974-
Eurasian city system dynamics in the last millennium
of city systems also needs to consider global warming and 45- 250 foot rises in ocean levels, largest
Dynamic Power Optimization Targeting User Delays in Interactive Systems
}@princeton.edu Abstract-- Power has become a major concern for mobile computing systems such as laptops and handhelds, on which a significant fraction of software usage is interactive instead of compute-intensive. For interactive systems, an analysis shows that over 90% of system energy and time is spent waiting for user input
Zhong, Lin
Efficient Transaction Support for Dynamic Information Retrieval Systems y
with database management system (DBMS) features. However, initial research has revealed that DBMS features efficiency is critical in IR systems, infrastructural extensions are necessary for several DBMS features with database management system (DBMS) features [Fuh93, BCCM94, DDS + 95]. However, ini tial findings have
Shenoy, Prashant
A study of the sensitivity of topological dynamical systems and the Fourier spectrum of chaotic interval maps
of lifting some topological properties from a given dynamical system (Y,S) to an- other (X,T). After studying some basic facts about topological dynamical systems, we move to the particular case of interval maps. We know that through the knowl- edge... discussion with some basic concepts of what a dynamical system is and how the dynamic is generated. Definition 2.1. A dynamical system (X,T) consists of a topological compact metric space X and a surjective, continuous map T : X ?X. The first thing we have...
Roque Sol, Marco A.
Gas hydrate research in the Gulf of Mexico: Final report
The high energy seismic sections on the continental slope showed no evidence of a Bottom Simulating Reflector (BSR), which would indicate the presence of gas hydrates. There was no indication of metastable hydrates in continental shelf or slope sediments outside of the conventionally accepted temperature and pressure environment. Tracing the path of migrating gas from the source is much more straight forward than intercepting gas being transported and tracing it back to the source. Our study of low and medium energy seismic methods has shown that they could identify migrating gas. We feel strongly that there are hydrate zones in the Gulf of Mexico that are decomposing; they build up pressure and periodically release the trapped hydrocarbon gases. The released gases migrate vertically and/or laterally to mix with other types of gas or to form discrete pockets. Some of this gas may be emitted from underwater seeps into the overlying water column where it could be identified by a geochemical survey. The ratio of isobutane to normal butane determined by the geochemical survey can be used to assess the probability of the hydrocarbons emanating from a hydrate source. (The more the ratio exceeds 1.0 the greater the probability that the gas could be from a hydrate source.) As no indications of a hydrate zone (e.g., a BSR) were located, we were not able to establish a geophysical signature for gas hydrates; but the records indicate there are large volumes of gas migrating up the continental slope, some of which may have originated from a decomposing hydrate zone or from gas trapped below the hydrate cap. 20 refs., 13 figs., 1 tab.
Bennet, R.
Driving force and composition for multicomponent gas hydrate nucleation from supersaturated aqueous solutions
formation in storage. Other interests include deep ocean carbon sequestration, use of hydrate deposits
E ects of the Driving Force on the Composition of Natural Gas Hydrates
E ects of the Driving Force on the Composition of Natural Gas Hydrates Odd I. Levik(1) , Jean for storage and transport of natural gas. Storage of natural gas in the form of hydrate at elevated pressure concept) (Gud- mundsson et al. 1998). Natural gas hydrate contains up to 182 Sm3 gas per m3 hydrate
Micromechanics of Hydrate Dissociation in Marine Sediments by Grain-Scale Simulations
dissociation on the strength of hydrate-bearing sediments. Dissociation of gas-hydrates in marine sediments. Introduction Gas-hydrates are solid materials formed under a range of high pressures and low temperatures seek to evaluate the mechanical response to dissoci- ation of gas-hydrates in marine sediments
Patzek, Tadeusz W.
Author's personal copy New surfactant for hydrate anti-agglomeration in hydrocarbon flowlines
Available online 10 April 2013 Keywords: Gas hydrates Hydrate anti-agglomeration Surfactants Surface adsorption a b s t r a c t Anti-agglomeration is a promising solution for gas hydrate risks in deepsea-friendly surfactant. �? 2013 Elsevier Inc. All rights reserved. 1. Introduction The formation of gas hydrates
Journal of Crystal Growth 243 (2002) 476489 Nucleation of gas hydrates
Journal of Crystal Growth 243 (2002) 476489 Nucleation of gas hydrates Dimo Kashchieva , Abbas of nucleation of one-component gas hydrates in aqueous solutions are analyzed. The size of the hydrate nucleus. Nucleation; B1. Gas hydrates 1. Introduction Nucleation is perhaps the most challenging step in understanding
Technology verification phase. Dynamic isotope power system. Final report
The Phase I requirements of the Kilowatt Isotope Power System (KIPS) program were to make a detailed Flight System Conceptual Design (FSCD) for an isotope fueled organic Rankine cycle power system and to build and test a Ground Demonstration System (GDS) which simulated as closely as possible the operational characteristics of the FSCD. The activities and results of Phase II, the Technology Verification Phase, of the program are reported. The objectives of this phase were to increase system efficiency to 18.1% by component development, to demonstrate system reliability by a 5000 h endurance test and to update the flight system design. During Phase II, system performance was improved from 15.1% to 16.6%, an endurance test of 2000 h was performed while the flight design analysis was limited to a study of the General Purpose Heat Source, a study of the regenerator manufacturing technique and analysis of the hardness of the system to a laser threat. It was concluded from these tests that the GDS is basically prototypic of a flight design; all components necessary for satisfactory operation were demonstrated successfully at the system level; over 11,000 total h of operation without any component failure attested to the inherent reliability of this type of system; and some further development is required, specifically in the area of performance. (LCL)
Halsey, D.G.
Simteche Hydrate CO2 Capture Process
As a result of an August 4, 2005 project review meeting held at Los Alamos National Laboratory (LANL) to assess the project's technical progress, Nexant/Simteche/LANL project team was asked to meet four targets related to the existing project efforts. The four targets were to be accomplished by the September 30, 2006. These four targets were: (1) The CO{sub 2} hydrate process needs to show, through engineering and sensitivity analysis, that it can achieve 90% CO{sub 2} capture from the treated syngas stream, operating at 1000 psia. The cost should indicate the potential of achieving the Sequestration Program's cost target of less than 10% increase in the cost of electricity (COE) of the non-CO{sub 2} removal IGCC plant or demonstrate a significant cost reduction from the Selexol process cost developed in the Phase II engineering analysis. (2) The ability to meet the 20% cost share requirement for research level efforts. (3) LANL identifies through equilibrium and bench scale testing a once-through 90% CO{sub 2} capture promoter that supports the potential to achieve the Sequestration Program's cost target. Nexant is to perform an engineering analysis case to verify any economic benefits, as needed; no ETM validation is required, however, for this promoter for FY06. (4) The CO{sub 2} hydrate once-through process is to be validated at 1000 psia with the ETM at a CO{sub 2} capture rate of 60% without H{sub 2}S. The performance of 68% rate of capture is based on a batch, equilibrium data with H{sub 2}S. Validation of the test results is required through multiple runs and engineering calculations. Operational issues will be solved that will specifically effect the validation of the technology. Nexant was given the primary responsibility for Target No.1, while Simteche was mainly responsible for Target No.2; with LANL having the responsibility of Targets No.3 and No.4.
Nexant and Los Alamos National Laboratory
Dynamic daylight control system implementing thin cast arrays of polydimethylsiloxane-based millimeter-scale transparent louvers
Dynamic daylight control system implementing thin cast arrays of polydimethylsiloxane: Daylight control system Dynamic window system Energy-efficiency Transparent louvers a b s t r a c in standard office buildings. The development of daylight control systems that maximize the penetration
Aizenberg, Joanna
Dynamic Scheduling of a Parallel Server System in Heavy Traffic with Complete Resource Pooling: Asymptotic Optimality of a
as the optimal cost in the Brownian control problem. Short title: Dynamic Scheduling of Parallel Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.3 Scheduling Control and Performance Measures . . . . . . . . . . . . . . . . . . . . . . . . 7Dynamic Scheduling of a Parallel Server System in Heavy Traffic with Complete Resource Pooling
Does a dynamical system lose energy by emitting gravitational waves?
We note that Eddington's radiation damping calculation of a spinning rod fails to account for the complete mass integral as given by Tolman. The missing stress contributions precisely cancel the standard rate given by the 'quadrupole formula'. This indicates that while the usual 'kinetic' term can properly account for dynamical changes in the source, the actual mass is conserved. Hence gravity waves are not carriers of energy in vacuum. This supports the hypothesis that energy including the gravitational contribution is confined to regions of non-vanishing energy-momentum tensor $T_{ik}$. PACS numbers: 04.20.Cv, 04.30.-w
F. I. Cooperstock
Rudd. 2007. Review of residential ventilation technologies.2009. EISG Final Report: Residential Integrated VentilationDesign and Operation of Residential Cooling Systems. Proc.
Sherman, Max H.
Adaptive Model Predictive Control of the Hybrid Dynamics of a Fuel Cell System.
Adaptive Model Predictive Control of the Hybrid Dynamics of a Fuel Cell System. M. Fiacchini, T operation of a fuel cell system is presented. The aim of the control design is to guarantee that the oxygen control to a fuel cell plant is presented. The fuel cell, located in the laboratory of the Department
Dynamic Key-Updating: Privacy-Preserving Authentication for RFID Systems , Jinsong Han2
Dynamic Key-Updating: Privacy-Preserving Authentication for RFID Systems Li Lu1 , Jinsong Han2 an emerging requirement protecting user privacy [13] in RFID authentications. In most RFID systems, tags sensitive information. For example, without pri- vacy protection, any reader can identify a consumer's ID
Liu, Yunhao
Exploring the free-energy landscapes of biological systems with steered molecular dynamics
1 Exploring the free-energy landscapes of biological systems with steered molecular dynamics fluctuation-dissipation-theorem (BD -FDT) to accurately compute the free-energy profiles for several compute the free-energy profiles for all the afore-listed systems that represent various important aspects
Chen, Liao Y.
Dynamic Reconfiguration of Photovoltaic Energy Harvesting System in Hybrid Electric Vehicles
Dynamic Reconfiguration of Photovoltaic Energy Harvesting System in Hybrid Electric Vehicles Yanzhi, xuelin, firstname.lastname@example.com, 2 {firstname.lastname@example.com ABSTRACT Photovoltaic (PV) energy harvesting system and Reliability]: Performance Analysis and Design Aids. General Terms Algorithms, Design, Management, Performance
Pedram, Massoud
The potential for dynamic distribution systems to create a new energy marketplace
photovoltaic (PV) systems has fallen, on average, six to seven percent every year since 1998 (Feldman & Barbose microgrid technology developed through the Consortium for Electric Reliability Technology Solutions (CERTS reliability. The challenge is to further develop the dynamic disitribution system technology, including its
Van Veen, Barry D.
A New Bifurcation Analysis for Power System Dynamic Voltage Stability Studies
a specific system configuration and the operation condition. For a power system, the typical state variables are the time dependent generator voltages (For different generator models, the variables of generator voltages as the variables of the exciter, speed governor and so on; sometimes the dynamics of the load behavior will also
Dynamics of hydrothermal seeps from the Salton Sea geothermal system (California, USA) constrained by temperature monitoring
Dynamics of hydrothermal seeps from the Salton Sea geothermal system (California, USA) constrained-, and petroleum-bearing seeps are part of the Salton Sea geothermal system (SSGS) in southern California. Carbon likely reflect a combination of hydrothermal flux variations from the SSGS and the local temporal changes
Svensen, Henrik
Product systems of Hilbert modules and their applications in quantum dynamics
Product systems of Hilbert modules and their applications in quantum dynamics Michael Skeide Markov endomorphisms), and dilations of the for- mer to the latter, are intimately related to and connected by product adjointable operators on a Hilbert Bmodule E, and the related product systems consist of correspon- dences
Schürmann, Michael
Dynamic Voltage Scaling for Systemwide Energy Minimization in Real-Time Embedded Systems
%. We show that our scheduling approach minimizes the total static and dynamic energy consumption increase the total energy consumption of the system. A minimum power consumption is associated with keeping the processorenergy consumption as opposed to the entire system energy consumption. The slowdown resulting from DVS
Gupta, Rajesh
Vehicle System Dynamics, Vol.25 suppl., 1996, pp.139-151 14th IAVSD Page 1
Vehicle System Dynamics, Vol.25 suppl., 1996, pp.139-151 14th IAVSD Page 1 Comparative Analyses of Three Types of Headway Control Systems for Heavy Commercial Vehicles P.S. FANCHER, H. PENG, and Z range and its derivative (range-rate) [3]. For heavy vehicles, the control unit has a number
Peng, Huei
A dynamical systems approach for the station keeping of a Solar Sail
A dynamical systems approach for the station keeping of a Solar Sail Ariadna Farr´es and `Angel considered the movement of a solar sail in the Sun - Earth system. As a model we have used the RTBP adding the solar radiation pressure. It can be seen that we have a 2D family of equilibria parametrised by the two
Barcelona, Universitat de
Time Series Prediction by Chaotic Modeling of Nonlinear Dynamical Systems Arslan Basharat+
Inc. Clifton Park, NY, USA email@example.com Mubarak Shah+ + University of Central Florida Orlando, FL, USA email@example.com Abstract We use concepts from chaos theory in order to model nonlinear dynamical systems that exhibit deterministic be- havior. Observed time series from such a system can be em
Central Florida, University of
System Dynamics and the Electric Power Industry Andrew Forda
States. I will pay particular attention to the difficult "energy crisis" years of the 1970s. I a gateway to an impressive body of work for system dynamicists interested in energy. Finally, and most planning at Washington State University. He was formerly a staff member of the Energy Systems and Policy
Ford, Andrew
On Controllability and Normality of Discrete Event Dynamical Systems
in the plant, can also occur in the closed loop system, there may not always exist a complete supervisor Dynami- cal Systems (DEDS's) through the use of synchronous composition of the plant and the supervisor is then used to derive an algorithm that is computationally more e cient than previously existing ones
Garg, Vijay
On Controllability and Normality of Discrete Event Dynamical Systems \\Lambda
that can occur in the plant, can also occur in the closed loop system, there may not always exist Event Dynami cal Systems (DEDS's) through the use of synchronous composition of the plant existing ones for the construction of the supremal controllable sublanguage; the algorithm is also shown
Stationary states and fractional dynamics in systems with long range interactions
Dynamics of many-body Hamiltonian systems with long range interactions is studied, in the context of the so called $\\alpha-$HMF model. Building on the analogy with the related mean field model, we construct stationary states of the $\\alpha-$HMF model for which the spatial organization satisfies a fractional equation. At variance, the microscopic dynamics turns out to be regular and explicitly known. As a consequence, dynamical regularity is achieved at the price of strong spatial complexity, namely a microscopic inhomogeneity which locally displays scale invariance.
Tineke L. Van Den Berg; Duccio Fanelli; Xavier Leoncini
Majorana path integral for nonequilibrium dynamics of two-level systems
We present a new field-theoretic approach to analyze nonequilibrium dynamics of two-level systems (TLS), which is based on a correspondence between a driven TLS and a Majorana fermion field theory coupled to bosonic fields. This approach allows us to calculate analytically properties of nonlinear TLS dynamics with an arbitrary accuracy. We apply our method to analyze specific TLS dynamics under a monochromatic periodic drive that is relevant to the problem of decoherence in Josephson junction qubits. It is demonstrated that the method gives the precise positions of the resonance peaks in the nonlinear dielectric response function that are in agreement with numerical simulations.
Sedrakyan, Tigran A.; Galitski, Victor M. [Condensed Matter Theory Center and Joint Quantum Institute, Department of Physics, University of Maryland, College Park, Maryland 20742 (United States)
Dynamic Response Optimization of Complex Multibody Systems in a Penalty Formulation using Adjoint Sensitivity
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.
Yitao Zhu; Daniel Dopico; Corina Sandu; Adrian Sandu
through the annular gravel pack (kg) N H = hydration numberthrough the annular gravel pack (kg/s) Q V = rate of CH 4ocean through the annular gravel pack (ST m 3 ) X i = water
Drilling Through Gas Hydrates Formations: Managing Wellbore Stability Risks
As hydrocarbon exploration and development moves into deeper water and onshore arctic environments, it becomes increasingly important to quantify the drilling hazards posed by gas hydrates. To address these concerns, a 1D semi-analytical model...
Khabibullin, Tagir R.
Drilling through gas hydrates formations: possible problems and suggested solution
Gas hydrate research in the last two decades has taken various directions ranging from ways to understand the safe and economical production of this enormous resource to drilling problems. as more rigs and production platforms move into deeper...
Amodu, Afolabi Ayoola
Carbon dioxide hydrate particles for ocean carbon sequestration
This paper presents strategies for producing negatively buoyant CO[subscript 2] hydrate composite particles for ocean carbon sequestration. Our study is based on recent field observations showing that a continuous-jet ...
Chow, A.C.
An Integrated Study Method For Exploration Of Gas Hydrate Reservoirs...
Open Energy Info (EERE)
approach for exploration of gas hydrate reservoirs in marine areas. Authors C. Y. Sun, B. H. Niu, P. F. Wen, Y. Y. Huang, H. Y. Wang, X. W. Huang and J. Li Published Journal...
. These slurries seems to be well appropriate for cold storage and transportation in the case of air- conditioning as secondary refrigerants. Concerning hydrates, they have been used as PCM for cold storage for years
Geotechnical characterization of sediments from Hydrate Ridge, Cascadia Continental Margin
Eight whole core sediment samples were obtained from ODP Site 1244, Hydrate Ridge, Cascadia Continental Margin with the goal of understanding the stress history, consolidation behavior and strength characteristics of the ...
Tan, Brian B. (Brian Bautista), 1979-
Fully coupled dynamic analysis of a floating wind turbine system
The use of wind power is in a period of rapid growth worldwide and wind energy systems have emerged as a promising technology for utilizing offshore wind resources for the large scale generation of electricity. Drawing ...
Withee, Jon E
Design of innovative dynamic systems for seismic response mitigation
Rocking wall systems consist of shear walls, laterally connected to a building, that are moment-released in their strong plane. Their purpose is to mitigate seismic structural response by constraining a building primarily ...
Seymour, Douglas (Douglas Benjamin)
Probabilistic Planning for Continuous Dynamic Systems under Bounded Risk
This paper presents a model-based planner called the Probabilistic Sulu Planner or the p-Sulu Planner, which controls stochastic systems in a goal directed manner within user-specified risk bounds. The objective of the ...
Williams, Brian Charles
System-environment dynamics of X-type states in noninertial frames
The system-environment dynamics of noninertial systems is investigated. It is shown that for the amplitude damping channel: (i) the biggest difference between the decoherence effect and the Unruh radiation on the dynamics of the entanglement is the former only leads to entanglement transfer in the whole system, but the latter damages all types of entanglement; (ii) the system-environment entanglement increases and then declines, while the environment-environment entanglement always increases as the decay parameter $p$ increases; and (iii) the thermal fields generated by the Unruh effect can promote the sudden death of entanglement between the subsystems while postpone the sudden birth of entanglement between the environments. It is also found that there is no system-environment and environment-environment entanglements when the system coupled with the phase damping environment.
Jieci Wang; Jiliang Jing
Identifications and Monitoring of Power System Dynamics Based on the PMUs and Wavelet Technique
Abstract�Low frequency power oscillations may be triggered by many events in the system. Most oscillations are damped by the system, but undamped oscillations can lead to system collapse. Oscillations develop as a result of rotor acceleration/deceleration following a change in active power transfer from a generator. Like the operations limits, the monitoring of power system oscillating modes is a relevant aspect of power system operation and control. Unprevented low-frequency power swings can be cause of cascading outages that can rapidly extend effect on wide region. On this regard, a Wide Area Monitoring, Protection and Control Systems (WAMPCS) help in detecting such phenomena and assess power system dynamics security. The monitoring of power system electromechanical oscillations is very important in the frame of modern power system management and control. In first part, this paper compares the different technique for identification of power system oscillations. Second part analyzes possible identification some power system dynamics behaviors Using Wide Area Monitoring Systems (WAMS) based on Phasor Measurement Units (PMUs) and wavelet technique. Keywords�Power system oscillations, Modal analysis, Prony, Wavelet, PMU, Wide Area Monitoring System.
Samir Avdakovic; Amir Nuhanovic
Using System Dynamics to Model the Transition to Biofuels in the United States: Preprint
Transitioning to a biofuels industry that is expected to displace about 30% of current U.S. gasoline consumption requires a robust biomass-to-biofuels system-of-systems that operates in concert with the existing markets. This paper discusses employing a system dynamics approach to investigate potential market penetration scenarios for cellulosic ethanol and to help government decision makers focus on areas with greatest potential.
Bush, B.; Duffy, M.; Sandor, D.; Peterson, S.
Modeling pure methane hydrate dissociation using a numerical simulator from a novel combination of X-ray computed tomography and macroscopic data
of predicted and measured methane gas production data within the heterogeneous porous methane hydrate sample.Global Distribution of Methane Hydrate in Ocean Hydrate.
Gupta, A.
Examination of core samples from the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope: Effects of retrieval and preservation
and handling of natural gas hydrate. GSC Bulletin, 544: 263-naturally occurring gas hydrates: the structures of methanefrom the Mount Elbert Gas Hydrate Stratigraphic Test Well,
Collett, T.J. Kneafsey, T.J., H. Liu, W. Winters, R. Boswell, R. Hunter, and T.S.
Analysis of core samples from the BPXA-DOE-USGS Mount Elbert gas hydrate stratigraphic test well: Insights into core disturbance and handling
and handling of natural gas hydrate. GSC Bulletin, 544: 263-naturally occurring gas hydrates: the structures of methaneDOE-USGS Mount Elbert gas hydrate stratigraphic test well:
Kneafsey, Timothy J.
Evaluation of a deposit in the vicinity of the PBU L-106 Site, North Slope, Alaska, for a potential long-term test of gas production from hydrates
of P, T, and gas and hydrate phase saturations (S G and SInternational Conference on Gas Hydrates, Vancouver, BritishM. 2008. Investigation of gas hydrate bearing sandstone
Investigation of gas hydrate-bearing sandstone reservoirs at the "Mount Elbert" stratigraphic test well, Milne Point, Alaska
In February 2007, the U.S. Department of Energy, BP Exploration (Alaska), Inc., and the U.S. Geological Survey conducted an extensive data collection effort at the "Mount Elbert #1" gas hydrates stratigraphic test well on the Alaska North Slope (ANS). The 22-day field program acquired significant gas hydrate-bearing reservoir data, including a full suite of open-hole well logs, over 500 feet of continuous core, and open-hole formation pressure response tests. Hole conditions, and therefore log data quality, were excellent due largely to the use of chilled oil-based drilling fluids. The logging program confirmed the existence of approximately 30 m of gashydrate saturated, fine-grained sand reservoir. Gas hydrate saturations were observed to range from 60% to 75% largely as a function of reservoir quality. Continuous wire-line coring operations (the first conducted on the ANS) achieved 85% recovery through 153 meters of section, providing more than 250 subsamples for analysis. The "Mount Elbert" data collection program culminated with open-hole tests of reservoir flow and pressure responses, as well as gas and water sample collection, using Schlumberger's Modular Formation Dynamics Tester (MDT) wireline tool. Four such tests, ranging from six to twelve hours duration, were conducted. This field program demonstrated the ability to safely and efficiently conduct a research-level openhole data acquisition program in shallow, sub-permafrost sediments. The program also demonstrated the soundness of the program's pre-drill gas hydrate characterization methods and increased confidence in gas hydrate resource assessment methodologies for the ANS.
Boswell, R.M.; Hunter, R. (ASRC Energy Services, Anchorage, AK); Collett, T. (USGS, Denver, CO); Digert, S. (BP Exploration (Alaska) Inc., Anchorage, AK); Hancock, S. (RPS Energy Canada, Calgary, Alberta, Canada); Weeks, M. (BP Exploration (Alaska) Inc., Anchorage, AK); Mt. Elbert Science Team
Design an optimum safety policy for personnel safety management - A system dynamic approach
Personnel safety management (PSM) ensures that employee's work conditions are healthy and safe by various proactive and reactive approaches. Nowadays it is a complex phenomenon because of increasing dynamic nature of organisations which results in an increase of accidents. An important part of accident prevention is to understand the existing system properly and make safety strategies for that system. System dynamics modelling appears to be an appropriate methodology to explore and make strategy for PSM. Many system dynamics models of industrial systems have been built entirely for specific host firms. This thesis illustrates an alternative approach. The generic system dynamics model of Personnel safety management was developed and tested in a host firm. The model was undergone various structural, behavioural and policy tests. The utility and effectiveness of model was further explored through modelling a safety scenario. In order to create effective safety policy under resource constraint, DOE (Design of experiment) was used. DOE uses classic designs, namely, fractional factorials and central composite designs. It used to make second order regression equation which serve as an objective function. That function was optimized under budget constraint and optimum value used for safety policy which shown greatest improvement in overall PSM. The outcome of this research indicates that personnel safety management model has the capability for acting as instruction tool to improve understanding of safety management and also as an aid to policy making.
Balaji, P. [The Glocal University, Mirzapur Pole, Delhi- Yamuntori Highway, Saharanpur 2470001 (India)
Notes 02. Dynamic response of second order mechanical systems
frequency. Is this response the maximum ever expected? Explain. Recall that system periodic response is () ( )cos( ) s Xt XHr t ?=?+ Solution. From the amplitude of FRF () 2 22 1 () 1(2) s X Hr X rr? == ?+ Set r=r a = 1.2 and |X... that u=m e/M, where m is the imbalance mass and e is its radial location ( ) 2 cosM XDXKXMu t++=?? #0;#5;#0;#5; #0;#5; Recall that system periodic response is () ( )cos( )Xt uHr t ?=?+ a) What is the value of damping ? necessary so...
San Andres, Luis
Dynamic programming applied to maximizing traffic flow in parallel systems
Solution of the problem The Triple-Route Model 33 CHAPTER I INTRODUCTION The control of traffic flow and congestion in freeway systems is a matter of increasing importance at a time when it. has become evident that it is impossible to construct... enough urban highway- to satisfy all of the traffic demand. It is necessary to seek ways to make more efficient u. e of existing freeways. Nattleworth (1, 2) and others (3, 4, 5, 6) have discussed various aspects of the control of freeway systems...
Anderson, Gerald Lee
Effect of temperature on the hydration of Portland cement blended with siliceous fly ash
The effect of temperature on the hydration of Portland cement pastes blended with 50 wt.% of siliceous fly ash is investigated within a temperature range of 7 to 80 �C. The elevation of temperature accelerates both the hydration of OPC and fly ash. Due to the enhanced pozzolanic reaction of the fly ash, the change of the composition of the C�S�H and the pore solution towards lower Ca and higher Al and Si concentrations is shifted towards earlier hydration times. Above 50 �C, the reaction of fly ash also contributes to the formation of siliceous hydrogarnet. At 80 �C, ettringite and AFm are destabilised and the released sulphate is partially incorporated into the C�S�H. The observed changes of the phase assemblage in dependence of the temperature are confirmed by thermodynamic modelling. The increasingly heterogeneous microstructure at elevated temperatures shows an increased density of the C�S�H and a higher coarse porosity. -- Highlights: �The reaction of quartz powder at 80 �C strongly enhances the compressive strength. �Almost no strength increase of fly ash blended OPC at 80 �C was found after 2 days. �Siliceous hydrogarnet is formed upon the reaction of fly ash at high temperatures. �Temperature dependent change of the system was simulated by thermodynamic modelling. �Destabilisation of ettringite above 50 �C correlates with sulphate content of C�S�H.
Deschner, Florian, E-mail: email@example.com [Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Concrete and Construction Chemistry, �berlandstrasse 129, 8600 D�bendorf (Switzerland)] [Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Concrete and Construction Chemistry, �berlandstrasse 129, 8600 D�bendorf (Switzerland); Lothenbach, Barbara; Winnefeld, Frank [Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Concrete and Construction Chemistry, �berlandstrasse 129, 8600 D�bendorf (Switzerland)] [Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Concrete and Construction Chemistry, �berlandstrasse 129, 8600 D�bendorf (Switzerland); Neubauer, J�rgen [GeoZentrum Nordbayern, Mineralogy, University of Erlangen-Nuremberg, 91054 Erlangen (Germany)] [GeoZentrum Nordbayern, Mineralogy, University of Erlangen-Nuremberg, 91054 Erlangen (Germany)
Previous selective dynamic compilation systems have demonstrated that dynamic compilation can achieve performance improvements
approaches are relatively easy for programmers to use, but are only as powerful as the optimizations system that includes more sophisti- cated and flexible analyses and transformations. DyC is able. We analyze the individual optimizations of DyC and assess their impact on perfor- mance collectively
Mock, Markus U.
Measurements of SCRF cavity dynamic heat load in horizontal test system
The Horizontal Test System (HTS) at Fermilab is currently testing fully assembled, dressed superconducting radio frequency (SCRF) cavities. These cavities are cooled in a bath of superfluid helium at 1.8K. Dissipated RF power from the cavities is a dynamic heat load on the cryogenic system. The magnitude of heat flux from these cavities into the helium is also an important variable for understanding cavity performance. Methods and hardware used to measure this dynamic heat load are presented. Results are presented from several cavity tests and testing accuracy is discussed.
DeGraff, B.D.; Bossert, R.J.; Pei, L.; Soyars, W.M.; /Fermilab
The dynamic information architecture system : an advanced simulation framework for military and civilian applications.
DIAS, the Dynamic Information Architecture System, is an object-oriented simulation system that was designed to provide an integrating framework in which new or legacy software applications can operate in a context-driven frame of reference. DIAS provides a flexible and extensible mechanism to allow disparate, and mixed language, software applications to interoperate. DIAS captures the dynamic interplay between different processes or phenomena in the same frame of reference. Finally, DIAS accommodates a broad range of analysis contexts, with widely varying spatial and temporal resolutions and fidelity.
Campbell, A. P.; Hummel, J. R.
Dynamic Interactions of PV units in Low Volatge Distribution Systems
. Abstract--Photovoltaic (PV) units along with other distributed energy resources (DERs) are located close by minimizing the negative interactions. Index Terms--Photovoltaic, negative interactions, distribution systems different DERs may react negatively and degrade reliability. There are several different measures
[Investigation of transitions from order to chaos in dynamical systems
This report briefly discusses the following topics on chaotic systems; numerical investigations of fast dynamo problem for stationary space-periodic flows with chaotic streamlines; analytical and numerical investigations of magnetic field generation by conducting flows with finite resistivity; and emittance growth in charged particle beams.
Black hole interacting with matter as a simple dynamical system
Recently, a variational principle has been derived from Einstein-Hilbert and a matter Lagrangian for the spherically symmetric system of a dust shell and a black hole. The so-called physical region of the phase space, which contains all physically meaningful states of the system defined by the variational principle, is specified; it has a complicated boundary. The principle is then transformed to new variables that remove some problems of the original formalism: the whole phase space is covered (in particular, the variables are regular at all horizons), the constraint has a polynomial form, and the constraint equation is uniquely solvable for two of the three conserved momenta. The solutions for the momenta are written down explicitly. The symmetry group of the system is studied. The equations of motion are derived from the transformed principle and are shown to be equivalent to the previous ones. Some lower-dimensional systems are constructed by exclusion of cyclic variables, and some of their properties are found.
P. Hajicek
Physical Media Independence: System Support for Dynamically Available Network Interfaces
(PMI) is the concept of making assumptions about a particular device explicit, detecting events which PMI. Based on device availability, the model iden- ti es implicit device-related assumptions made the Interface Man- agement Module (IMM), that supports PMI in the FreeBSD operating system. The bene ts
Walpole, Jonathan
Efficient Transaction Support for Dynamic Information Retrieval Systems
are on to integrate IR features with database manage ment system (DBMS) features. However, initial research has revealed that DBMS features optimized for traditional databases, display degraded performance while are necessary for several DBMS fea tures, transaction support being one of them. This paper focuses
Massachusetts at Amherst, University of
A Dynamic Matching and Scheduling Algorithm for Heterogeneous Computing Systems
A heterogeneous computing system provides a variety of different machines, orchestrated to perform an application Maheswaran and Howard Jay Siegel Parallel Processing Laboratory