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Articles 991 - 1020 of 1413

Full-Text Articles in Physical Sciences and Mathematics

Data-Based Perfect-Deficit Approach To Understanding Climate Extremes And Forest Carbon Assimilation Capacity, Suhua Wei, Chuixiang Yi, George Hendrey, Timothy Eaton, Gerald Rustic, Shaoqiang Wang, Heping Liu, Nir Y. Krakauer, Weiguo Wang, Ankur R. Desai, Leonardo Montagnani, Kyaw Tha Paw U, Matthias Falk, Andrew Black, Christian Bernhofer, Thomas Grünwald, Tuomas Laurila, Alessandro Cescatti, Eddy Moors, Rosvel Bracho, Riccardo Valentini Jun 2014

Data-Based Perfect-Deficit Approach To Understanding Climate Extremes And Forest Carbon Assimilation Capacity, Suhua Wei, Chuixiang Yi, George Hendrey, Timothy Eaton, Gerald Rustic, Shaoqiang Wang, Heping Liu, Nir Y. Krakauer, Weiguo Wang, Ankur R. Desai, Leonardo Montagnani, Kyaw Tha Paw U, Matthias Falk, Andrew Black, Christian Bernhofer, Thomas Grünwald, Tuomas Laurila, Alessandro Cescatti, Eddy Moors, Rosvel Bracho, Riccardo Valentini

Publications and Research

Several lines of evidence suggest that the warming climate plays a vital role in driving certain types of extreme weather. The impact of warming and of extreme weather on forest carbon assimilation capacity is poorly known. Filling this knowledge gap is critical towards understanding the amount of carbon that forests can hold. Here, we used a perfect-deficit approach to identify forest canopy photosynthetic capacity (CPC) deficits and analyze how they correlate to climate extremes, based on observational data measured by the eddy covariance method at 27 forest sites over 146 site-years. We found that droughts severely affect the carbon assimilation …

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China’S Water Sustainability In The 21st Century: A Climate-Informed Water Risk Assessment Covering Multi-Sector Water Demands, X. Chen, Naresh Devineni, L. Upmanu, Z. Hao, L. Dong, Q. Ju, J. Wang, S. Wang May 2014

China’S Water Sustainability In The 21st Century: A Climate-Informed Water Risk Assessment Covering Multi-Sector Water Demands, X. Chen, Naresh Devineni, L. Upmanu, Z. Hao, L. Dong, Q. Ju, J. Wang, S. Wang

Publications and Research

China is facing a water resources crisis with growing concerns as to the reliable supply of water for agricultural, industrial and domestic needs. High inter-annual rainfall variability and increasing consumptive use across the country exacerbates the situation further and is a constraint on future development. For water sustainability, it is necessary to examine the differences in water demand and supply and their spatio-temporal distribution in order to quantify the dimensions of the water risk. Here, a detailed quantitative assessment of water risk as measured by the spatial distribution of cumulated deficits for China is presented. Considering daily precipitation and temperature …

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Intelligent Sampling For Big Data Using Bootstrap Sampling And Chebyshev Inequality, Ashwin Satyanarayana May 2014

Intelligent Sampling For Big Data Using Bootstrap Sampling And Chebyshev Inequality, Ashwin Satyanarayana

Publications and Research

The amount of data being generated and stored is growing exponentially, owed in part to the continuing advances in computer technology. These data present tremendous opportunities in data mining, a burgeoning field in computer science that focuses on the development of methods that can extract knowledge from data. In many real world problems, these data mining algorithms have access to massive amounts of data. Mining all the available data is prohibitive due to computational (time and memory) constraints. Much of the current research is concerned with scaling up data mining algorithms (i.e. improving on existing data mining algorithms for larger …

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1207-3900_Opt_Mage, Jonathan Gagné Apr 2014

1207-3900_Opt_Mage, Jonathan Gagné

Publications and Research

No abstract provided.

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1207-3900_Nir_Spex, Jonathan Gagné Apr 2014

1207-3900_Nir_Spex, Jonathan Gagné

Publications and Research

No abstract provided.

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Multi-Leg One-Loop Massive Amplitudes From Integrand Reduction Via Laurent Expansion, Hans Van Deurzen, Gionata Luisoni, Pierpaolo Mastrolia, Edoardo Mirabella, Giovanni Ossola, Tiziano Peraro Mar 2014

Multi-Leg One-Loop Massive Amplitudes From Integrand Reduction Via Laurent Expansion, Hans Van Deurzen, Gionata Luisoni, Pierpaolo Mastrolia, Edoardo Mirabella, Giovanni Ossola, Tiziano Peraro

Publications and Research

We present the application of a novel reduction technique for one-loop scattering amplitudes based on the combination of the integrand reduction and Laurent expansion. We describe the general features of its implementation in the computer code Ninja, and its interface to GoSam. We apply the new reduction to a series of selected processes involving massive particles, from six to eight legs.

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Uranium And Radon In Private Bedrock Well Water In Maine: Geospatial Analysis At Two Scales, Qiang Yang, Paul Smitherman, C. T. Hess, Charles W. Culbertson, Robert G. Marvinney, Andrew E. Smith, Yan Zheng Mar 2014

Uranium And Radon In Private Bedrock Well Water In Maine: Geospatial Analysis At Two Scales, Qiang Yang, Paul Smitherman, C. T. Hess, Charles W. Culbertson, Robert G. Marvinney, Andrew E. Smith, Yan Zheng

Publications and Research

In greater Augusta of central Maine, 53 out of 1093 (4.8%) private bedrock well water samples from 1534 km2 contained [U] >30 μg/L, the U.S. Environmental Protection Agency’s (EPA) Maximum Contaminant Level (MCL) for drinking water; and 226 out of 786 (29%) samples from 1135 km2 showed [Rn] >4,000 pCi/L (148 Bq/L), the U.S. EPA’s Alternative MCL. Groundwater pH, calcite dissolution and redox condition are factors controlling the distribution of groundwater U but not Rn due to their divergent chemical and hydrological properties. Groundwater U is associated with incompatible elements (S, As, Mo, F, and Cs) in water samples within …

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Economic Growth Assumptions In Climate And Energy Policy, Nir Y. Krakauer Mar 2014

Economic Growth Assumptions In Climate And Energy Policy, Nir Y. Krakauer

Publications and Research

The assumption that the economic growth seen in recent decades will continue has dominated the discussion of future greenhouse gas emissions and the mitigation of and adaptation to climate change. Given that long-term economic growth is uncertain, the impacts of a wide range of growth trajectories should be considered. In particular, slower economic growth would imply that future generations will be relatively less able to invest in emissions controls or adapt to the detrimental impacts of climate change. Taking into consideration the possibility of economic slowdown therefore heightens the urgency of reducing greenhouse gas emissions now by moving to renewable …

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Nnll Momentum-Space Resummation For Stop-Pair Production At The Lhc, Alessandro Broggio, Andrea Ferroglia, Matthias Neubert, Leonardo Vernazza, Li Lin Yang Mar 2014

Nnll Momentum-Space Resummation For Stop-Pair Production At The Lhc, Alessandro Broggio, Andrea Ferroglia, Matthias Neubert, Leonardo Vernazza, Li Lin Yang

Publications and Research

If supersymmetry near the TeV scale is realized in Nature, the pair production of scalar top squarks is expected to be observable at the Large Hadron Collider. Recently, effective field-theory methods were employed to obtain approximate predictions for the cross section for this process, which include soft-gluon emission effects up to nextto- next-to-leading order (NNLO) in perturbation theory. In this work we employ the same techniques to resum soft-gluon emission effects to all orders in perturbation theory and with next-to-next-to-logarithmic (NNLL) accuracy. We analyze the effects of NNLL resummation on the stop-pair production cross section by obtaining NLO+NNLL predictions in …

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Synergism Between Airborne Singlet Oxygen And A Trisubstituted Olefin Sulfonate For The Inactivation Of Bacteria, Rajib Choudhury, Alexander Greer Mar 2014

Synergism Between Airborne Singlet Oxygen And A Trisubstituted Olefin Sulfonate For The Inactivation Of Bacteria, Rajib Choudhury, Alexander Greer

Publications and Research

The reactivity of a trisubstituted alkene surfactant (8-methylnon-7-ene-1 sulfonate, 1) to airborne singlet oxygen in a solution containing E. coli was examined. Surfactant 1 was prepared by a Strecker-type reaction of 9-bromo-2-methylnon-2-ene with sodium sulfite. Submicellar concentrations of 1 were used that reacted with singlet oxygen by an “ene” reaction to yield two hydroperoxides (7-hydroperoxy-8-methylnon-8-ene-1 sulfonate and (E)-8-hydroperoxy-8-methylnon-6-ene-1 sulfonate) in a 4:1 ratio. Exchanging the H2O solution for D2O where the lifetime of solution-phase singlet oxygen increases by 20-fold led to an ∼2-fold increase in the yield of hydroperoxides pointing to surface activity …

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Cretaceous-Paleogene Dinoflagellate Biostratigraphy And The Age Of The Clayton Formation, Southeastern Missouri, Usa, Natalie R. Dastas, John A. Chamberlain Jr., Matthew P. Garb Mar 2014

Cretaceous-Paleogene Dinoflagellate Biostratigraphy And The Age Of The Clayton Formation, Southeastern Missouri, Usa, Natalie R. Dastas, John A. Chamberlain Jr., Matthew P. Garb

Publications and Research

Sedimentary deposits in Stoddard County, southeastern Missouri, reveal a K-Pg transition sequence represented by the uppermost Maastrichtian Owl Creek Formation and the Paleocene Clayton Formation. The Clayton Formation is characterized by a basal fossiliferous coquinite that contains reworked late Maastrichtian macrofossils. Dinoflagellate biostratigraphy is used to determine the age of the coquinite layer and specifically whether or not it is an end-K tsunamite deposit resulting from the Chicxulub impact event. Results indicate a mixed assemblage of late Maastrichtian and early Danian dinocysts within the basal coquinite of the Clayton Formation. Maastrichtian dinocyst taxa identified are Riculacysta amplexa, Pierceites pentagonus, Phelodinium …

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Capping Amyloid Β‑Sheets Of The Tau-Amyloid Structure Vqivyk With Hexapeptides Designed To Arrest Growth. An Oniom And Density Functional Theory Study, Joshua A. Plumley, Jorge Ali-Torres, Gabor Pohl, J. J. Dannenberg Mar 2014

Capping Amyloid Β‑Sheets Of The Tau-Amyloid Structure Vqivyk With Hexapeptides Designed To Arrest Growth. An Oniom And Density Functional Theory Study, Joshua A. Plumley, Jorge Ali-Torres, Gabor Pohl, J. J. Dannenberg

Publications and Research

We present ONIOM calculations using density functional theory (DFT) as the high and AM1 as the medium level that explore the abilities of different hexapeptide sequences to terminate the growth of a model for the tau-amyloid implicated in Alzheimer’s disease. We delineate and explore several design principles (H-bonding in the side chains, using antiparallel interactions on the growing edge of a parallel sheet, using all-D residues to form rippled interactions at the edge of the sheet, and replacing the H-bond donor N−H’s that inhibit further growth) that can be used individually and in combination to design such peptides that will …

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Groundwater Flow Across Spatial Scales: Importance For Climate Modeling, Nir Krakauer, Haibin Li, Ying Fan Mar 2014

Groundwater Flow Across Spatial Scales: Importance For Climate Modeling, Nir Krakauer, Haibin Li, Ying Fan

Publications and Research

Current regional and global climate models generally do not represent groundwater flow between grid cells as a component of the water budget. We estimate the magnitude of between cell groundwater flow as a function of grid cell size by aggregating results from a numerical model of equilibrium groundwater flow run and validated globally. We find that over a broad range of cell sizes spanning that of state of the art regional and global climate models, mean between cell groundwater flow magnitudes scale with the reciprocal of grid cell length. We also derive this scaling a priori from a simple statistical …

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Intramolecular Nitrogen Delivery For The Synthesis Of C-Glycosphingolipids. Application To The C-Glycoside Of The Immunostimulant Krn7000, Ahmad Sabri Altiti, David R. Mootoo Feb 2014

Intramolecular Nitrogen Delivery For The Synthesis Of C-Glycosphingolipids. Application To The C-Glycoside Of The Immunostimulant Krn7000, Ahmad Sabri Altiti, David R. Mootoo

Publications and Research

The key reaction in this approach to C-glycosphingolipids is the stereoselective iodocyclization of a sugar-linked homoallylic carbonimidothioate. E and Z reaction substrates were assembled in a convergent fashion via an alkene metathesis strategy and exhibited the same alkene facial selectivity in the iodocyclization irrespective of alkene geometry, although the E alkene was found to be less reactive.

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Are Climate Model Simulations Useful For Forecasting Precipitation Trends? Hindcast And Synthetic-Data Experiments, Nir Y. Krakauer, Balázs M. Fekete Feb 2014

Are Climate Model Simulations Useful For Forecasting Precipitation Trends? Hindcast And Synthetic-Data Experiments, Nir Y. Krakauer, Balázs M. Fekete

Publications and Research

Water scientists and managers currently face the question of whether trends in climate variables that affect water supplies and hazards can be anticipated. We investigate to what extent climate model simulations may provide accurate forecasts of future hydrologic nonstationarity in the form of changes in precipitation amount. We compare gridded station observations (GPCC Full Data Product, 1901–2010) and climate model outputs (CMIP5 Historical and RCP8.5 simulations, 1901–2100) in real and syntheticdata hindcast experiments. The hindcast experiments show that imputing precipitation trends based on the climate model mean reduced the root mean square error of precipitation trend estimates for 1961–2010 by …

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A Review Of Air–Ice Chemical And Physical Interactions (Aici): Liquids, Quasi-Liquids, And Solids In Snow, T. Bartels-Rausch, H-W Jacobi, T. F. Kahan, J. L. Thomas, E. S. Thomson, J. P. D. Abbatt, M. Ammann, J. R. Blackford, H. Bluhm, Chris Boxe, F. Domine, M. M. Frey, I. Gladich, M. I. Guzmán, D. Heger, Th. Huthwelker, P. Klán, W. F. Kuhs, M. H. Kuo, S. Maus, S. G. Moussa, V. F. Mcneill, J. T. Newberg, J. B. C. Pettersson, M. Roeselová, J. R. Sodeau Feb 2014

A Review Of Air–Ice Chemical And Physical Interactions (Aici): Liquids, Quasi-Liquids, And Solids In Snow, T. Bartels-Rausch, H-W Jacobi, T. F. Kahan, J. L. Thomas, E. S. Thomson, J. P. D. Abbatt, M. Ammann, J. R. Blackford, H. Bluhm, Chris Boxe, F. Domine, M. M. Frey, I. Gladich, M. I. Guzmán, D. Heger, Th. Huthwelker, P. Klán, W. F. Kuhs, M. H. Kuo, S. Maus, S. G. Moussa, V. F. Mcneill, J. T. Newberg, J. B. C. Pettersson, M. Roeselová, J. R. Sodeau

Publications and Research

Snow in the environment acts as a host to rich chemistry and provides a matrix for physical exchange of contaminants within the ecosystem. The goal of this review is to summarise the current state of knowledge of physical processes and chemical reactivity in surface snow with relevance to polar regions. It focuses on a description of impurities in distinct compartments present in surface snow, such as snow crystals, grain boundaries, crystal surfaces, and liquid parts. It emphasises the microscopic description of the ice surface and its link with the environment. Distinct differences between the disordered air–ice interface, often termed quasi-liquid …

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Deconstructing A Plant Macromolecular Assembly: Chemical Architecture, Molecular Flexibility, And Mechanical Performance Of Natural And Engineered Potato Suberins, Olga Serra, Subhasish Chatterjee, Merce Figueras, Marisa Molinas, Ruth E. Stark Feb 2014

Deconstructing A Plant Macromolecular Assembly: Chemical Architecture, Molecular Flexibility, And Mechanical Performance Of Natural And Engineered Potato Suberins, Olga Serra, Subhasish Chatterjee, Merce Figueras, Marisa Molinas, Ruth E. Stark

Publications and Research

Periderms present in plant barks are essential protective barriers to water diffusion, mechanical breakdown, and pathogenic invasion. They consist of densely packed layers of dead cells with cell walls that are embedded with suberin. Understanding the interplay of molecular structure, dynamics, and biomechanics in these cell wall-associated insoluble amorphous polymeric assemblies presents substantial investigative challenges. We report solid-state NMR coordinated with FT-IR and tensile strength measurements for periderms from native and wound-healing potatoes and from potatoes with genetically modified suberins. The analyses include the intact suberin aromatic; aliphatic polymer and cell-wall polysaccharides, previously reported soluble depolymerized transmethylation products, and undegraded …

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Cyclic Phosphonium Ionic Liquids, Sharon I. Lall-Ramnarine, Joshua A. Mukhlall, James F. Wishart, Robert R. Engel, Alicia R. Romeo, Masao Gohdo, Sharon Ramati, Marc B. Berman, Sophia N. Suarez Jan 2014

Cyclic Phosphonium Ionic Liquids, Sharon I. Lall-Ramnarine, Joshua A. Mukhlall, James F. Wishart, Robert R. Engel, Alicia R. Romeo, Masao Gohdo, Sharon Ramati, Marc B. Berman, Sophia N. Suarez

Publications and Research

Ionic liquids (ILs) incorporating cyclic phosphonium cations are a novel category of materials. We report here on the synthesis and characterization of four new cyclic phosphonium bis(trifluoromethylsulfonyl)amide ILs with aliphatic and aromatic pendant groups. In addition to the syntheses of these novel materials, we report on a comparison of their properties with their ammonium congeners. These exemplars are slightly less conductive and have slightly smaller self-diffusion coefficients than their cyclic ammonium congeners.

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Impacts Of Aerosol Particle Size Distribution And Land Cover Land Use On Precipitation In A Coastal Urban Environment Using A Cloud-Resolving Mesoscale Model, Nathan Hosannah, Jorge Gonzalez Jan 2014

Impacts Of Aerosol Particle Size Distribution And Land Cover Land Use On Precipitation In A Coastal Urban Environment Using A Cloud-Resolving Mesoscale Model, Nathan Hosannah, Jorge Gonzalez

Publications and Research

Urban environments influence precipitation formation via response to dynamic effects, while aerosols are intrinsically necessary for rainfall formation; however, the partial contributions of each on urban coastal precipitation are not yet known.Here, the authors use aerosol particle size distributions derived from the NASA aerosol robotic network (AERONET) to estimate submicron cloud condensation nuclei (CCN) and supermicron CCN (GCCN) for ingestion in the regional atmospheric modeling system (RAMS). High resolution land data from the National Land Cover Database (NLCD) were assimilated into RAMS to provide modern land cover and land use (LCLU).Thefirst two of eight total simulationswere month long runs for …

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Wave Function For Harmonically Confined Electrons In Time-Dependent Electric And Magnetostatic Fields, Hong-Ming Zhu, Jin-Wang Chen, Xiao-Yin Pan, Viraht Sahni Jan 2014

Wave Function For Harmonically Confined Electrons In Time-Dependent Electric And Magnetostatic Fields, Hong-Ming Zhu, Jin-Wang Chen, Xiao-Yin Pan, Viraht Sahni

Publications and Research

We derive via the interaction “representation” the many-body wave function for harmonically confined electrons in the presence of a magnetostatic field and perturbed by a spatially homogeneous time-dependent electric field—the Generalized Kohn Theorem (GKT) wave function. In the absence of the harmonic confinement – the uniform electron gas – the GKT wave function reduces to the Kohn Theorem wave function. Without the magnetostatic field, the GKTwave function is the Harmonic Potential Theorem wave function. We further prove the validity of the connection between the GKT wave function derived and the system in an accelerated frame of reference. Finally, we provide …

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Boosted Top Production: Factorization And Resummation For Single-Particle Inclusive Distributions, Andrea Ferroglia, Simone Marzani, Ben D. Pecjak, Li Lin Yang Jan 2014

Boosted Top Production: Factorization And Resummation For Single-Particle Inclusive Distributions, Andrea Ferroglia, Simone Marzani, Ben D. Pecjak, Li Lin Yang

Publications and Research

We study single-particle inclusive (1PI) distributions in top-quark pair production at hadron colliders, working in the highly boosted regime where the top-quarkpTis much larger than its mass. In particular, we derive a novel factorization formula validin the small-mass and soft limits of the differential partonic cross section. This providesa framework for the simultaneous resummation of soft gluon corrections and small-mass logarithms, and also an efficient means of obtaining higher-order corrections to the differential cross section in this limit. The result involves five distinct one-scale functions, three of which arise through the subfactorization of soft real radiation in the small-mass limit. …

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Investigation Of The Structure Of The Few Body Kaonic Nuclei Using The Method Of Hyperspherical Functions In Momentum Space, Roman Ya. Kezerashvili, Shalva M. Tsiklauri Jan 2014

Investigation Of The Structure Of The Few Body Kaonic Nuclei Using The Method Of Hyperspherical Functions In Momentum Space, Roman Ya. Kezerashvili, Shalva M. Tsiklauri

Publications and Research

The kaonic clusters KNN and KNNN are studied within the method of hyperspherical functions in the momentum representation. Binding energies and widths of three- and four-body nuclear quasibound states are calculated by employing realistic NN potentials and the energy dependent chiral KN interaction, as well as a phenomenological KN potential. The comparison of the results of calculations obtained in the framework of the variational method, Faddeev, Faddeev-Yakubovsky equations, and method of hyperspherical functions in configuration space are discussed.

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Environmental Science For The Curious: My Perspective On Curiosity And Personal Satisfaction. In: Environmental Science For The Curious (K. Vaidya, Ed.), Aldemaro Romero Jr. Jan 2014

Environmental Science For The Curious: My Perspective On Curiosity And Personal Satisfaction. In: Environmental Science For The Curious (K. Vaidya, Ed.), Aldemaro Romero Jr.

Publications and Research

No abstract provided.

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Virtual Cut-Through: A New Computer Communication Switching Technique, Parviz Kermani, Leonard Kleinrock Jan 2014

Virtual Cut-Through: A New Computer Communication Switching Technique, Parviz Kermani, Leonard Kleinrock

Publications and Research

No abstract provided.

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Evolutionary Algorithm Based Approach For Modeling Autonomously Trading Agents, Anil Yaman, Stephen Lucci, Izidor Gertner Jan 2014

Evolutionary Algorithm Based Approach For Modeling Autonomously Trading Agents, Anil Yaman, Stephen Lucci, Izidor Gertner

Publications and Research

The autonomously trading agents described in this paper produce a decision to act such as: buy, sell or hold, based on the input data. In this work, we have simulated autonomously trading agents using the Echo State Network (ESNs) model. We generate a collection of trading agents that use different trading strategies using Evolutionary Programming (EP). The agents are tested on EUR/ USD real market data. The main goal of this study is to test the overall performance of this collection of agents when they are active simultaneously. Simulation results show that using different agents concurrently outperform a single agent …

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Algebraic Formulation Of Hadronic Supersymmetry Based On Octonions: New Mass Formulas And Further Applications, Sultan Catto, Yasemin Gürcan, Amish Khalfan, Levent Kurt Jan 2014

Algebraic Formulation Of Hadronic Supersymmetry Based On Octonions: New Mass Formulas And Further Applications, Sultan Catto, Yasemin Gürcan, Amish Khalfan, Levent Kurt

Publications and Research

A special treatment based on the highest division algebra, that of octonions and their split algebraic formulation is developed for the description of diquark states made up of two quark pairs. We describe symmetry properties of mesons and baryons through such formulation and derive mass formulae relating π, ρ, N and Δ trajectories showing an incredible agreement with experiments. We also comment on formation of diquark-antidiquark as well as pentaquark states and point the way toward applications into multiquark formulations expected to be seen at upcoming CERN experiments. A discussion on relationship of our work to flux bag models, string …

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Generalized Least-Squares Regressions Iii: Further Theory And Classification, Nataniel Greene Jan 2014

Generalized Least-Squares Regressions Iii: Further Theory And Classification, Nataniel Greene

Publications and Research

This paper continues the work of this series with two results. The first is an exponential equivalence theorem which states that every generalized least-squares regression line can be generated by an equivalent exponential regression. It follows that every generalized least-squares line has an effective normalized exponential parameter between 0 and 1 which classifies the line on the spectrum between ordinary least-squares and the extremal line for a given set of data. The second result is the presentation of fundamental formulas for the generalized least-squares slope and y-intercept.

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Sensitivity Of Orbiting Jem-Euso To Large-Scale Cosmic-Ray Anisotropies, Peter B. Denton, Luis A. Anchordoqui, Andreas A. Berlind, Matthew Richardson, Thomas J. Weiler Jan 2014

Sensitivity Of Orbiting Jem-Euso To Large-Scale Cosmic-Ray Anisotropies, Peter B. Denton, Luis A. Anchordoqui, Andreas A. Berlind, Matthew Richardson, Thomas J. Weiler

Publications and Research

The two main advantages of space-based observation of extreme-energy (& 1019 eV) cosmic-rays (EECRs) over ground-based observatories are the increased field of view, and the all- sky coverage with nearly uniform systematics of an orbiting observatory. The former guarantees increased statistics, whereas the latter enables a partitioning of the sky into spherical harmonics. We have begun an investigation, using the spherical harmonic technique, of the reach of JEM- EUSO into potential anisotropies in the extreme-energy cosmic-ray sky-map. The technique is explained here, and simulations are presented. The discovery of anisotropies would help to identify the long-sought origin of EECRs.

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Brownfield Action: Dissemination Of A Sencer Model Curriculum And The Creation Of A Collaborative Stem Education Network, Peter Bower, Ryan Kelsey, Joseph Liddicoat, Doug M. Thompson, Angelo Lampousis, Bret Bennington, Bess Greenbaum Seewald, Arthur D. Kney, Saugata Datta, Lawrence D. Lemke, Briane Sorice Miccio, Tamara Graham Jan 2014

Brownfield Action: Dissemination Of A Sencer Model Curriculum And The Creation Of A Collaborative Stem Education Network, Peter Bower, Ryan Kelsey, Joseph Liddicoat, Doug M. Thompson, Angelo Lampousis, Bret Bennington, Bess Greenbaum Seewald, Arthur D. Kney, Saugata Datta, Lawrence D. Lemke, Briane Sorice Miccio, Tamara Graham

Publications and Research

Brownfield Action (BA) is a web-based environmental site assessment (ESA) simulation in which students form geotechnical consulting companies and work together to solve problems in environmental forensics. Developed at Barnard College with the Columbia Center for New Media Teaching and Learning, BA has been disseminated to ten colleges, universities, and high schools, resulting in a collaborative network of educators. The experiences of current users are presented describing how they have incorporated the BA curriculum into their courses, as well as how BA affected teaching and learning. The experiences demonstrate that BA can be used in whole or in part, is …

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Relativistic Particle And Relativistic Fluids: Magnetic Moment And Spin-Orbit Interactions, V. Parameswaran Nair, Dimitra Karabali Jan 2014

Relativistic Particle And Relativistic Fluids: Magnetic Moment And Spin-Orbit Interactions, V. Parameswaran Nair, Dimitra Karabali

Publications and Research

We consider relativistic charged particle dynamics and relativistic magnetohydrodynamics using symplectic structures and actions given in terms of co-adjoint orbits of the Poincare group. The particle case is meant to clarify some points such as how minimal coupling (as defined in text) leads to a gyromagnetic ratio g = 2, and to set the stage for fluid dynamics. The general group-theoretic framework is further explained and is then used to set up Abelian magnetohydrodynamics including spin effects. An interesting new physical effect is precession of spin density induced by gradients in pressure and energy density. The Euler equation (the dynamics …

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