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Inversion of spectral absorption coefficients to infer phytoplankton size classes, chlorophyll concentration, and detrital matter

Xiaodong Zhang, Yannick Huot, Annick Bricaud, Heidi M. Sosik
2015 Applied Optics  
We validated the inversion with three datasets: two spatially distributed global datasets, the Laboratoire d'Océanographie de Villefranche dataset and the NASA bio-Optical Marine Algorithm Dataset, and  ...  The results indicate that the chlorophyll-a specific absorption spectra used as an inversion kernel represent well the global mean states for each of the three phytoplankton size classes.  ...  Meridional transects in the Atlantic (NOMAD dataset) show that each of the three size fractions can dominate.  ... 
doi:10.1364/ao.54.005805 pmid:26193033 fatcat:3op4kufmwzgfdntpyemsv5otgu

Rock Fracture Monitoring Based on High-Precision Microseismic Event Location Using 3D Multiscale Waveform Inversion

Yi Wang, Xueyi Shang, Kang Peng, Rui Gao, Yanlin Zhao
2020 Geofluids  
Furthermore, the multiscale waveform inversion method can obtain a similar location accuracy compared with the waveform inversion based on a single fine grid, and it can significantly decrease the iteration  ...  On this basis, the wavefields were modeled by utilizing a high-resolution 3D velocity model, a fractional-order Gaussian wavelet source-time function, and spectral element method (SEM) wavefield modeling  ...  For a windowed waveform, the observed waveforms can be fitted by adjusting the fractional order u and the dominant frequency w 0 of a fractional-order Gaussian function.  ... 
doi:10.1155/2020/8825140 fatcat:bb2vxom2tjdptjyxhrxz7wrwlm

A Simultaneous Inversion Problem for the Variable-Order Time Fractional Differential Equation with Variable Coefficient

Shengnan Wang, Zhendong Wang, Gongsheng Li, Yingmei Wang
2019 Mathematical Problems in Engineering  
This paper deals with an inverse problem of simultaneously determining the space-dependent diffusion coefficient and the fractional order in the variable-order time fractional diffusion equation by the  ...  Numerical solution to the forward problem is given by the finite difference scheme, and the homotopy regularization algorithm is applied to solve the inverse problem utilizing Legendre polynomials as the  ...  Acknowledgments This work is partially supported by the National Natural Science Foundation of China (nos. 11371231 and 11871313).  ... 
doi:10.1155/2019/2562580 fatcat:favew7pdx5coxmpkquejzr7sqm

fPINNs: Fractional Physics-Informed Neural Networks [article]

Guofei Pang, Lu Lu, George Em Karniadakis
2018 arXiv   pre-print
Finally, we solve several inverse problems in 1D, 2D, and 3D to identify the fractional orders, diffusion coefficients, and transport velocities and obtain accurate results even in the presence of significant  ...  We extend PINNs to fractional PINNs (fPINNs) to solve space-time fractional advection-diffusion equations (fractional ADEs), and we demonstrate their accuracy and effectiveness in solving multi-dimensional  ...  Acknowledgements We would like to acknowledge support from the Army Research Office (ARO) W911NF-18-1-0301, ARO MURI W911NF-15-1-0562, and the Department of Energy (DOE) DESC0019434, de-sc0019453.  ... 
arXiv:1811.08967v1 fatcat:jc64u5ka4bg3tlhcvrqm6bg53y

Micromechanical devices with controllable stiffness fabricated from regular 3D porous materials

James H Pikul, Zhenting Dai, Xindi Yu, Huigang Zhang, Taewan Kim, Paul V Braun, William P King
2014 Journal of Micromechanics and Microengineering  
The template technique allows 3D spatial control of the ordered porous structure and the ability to use a broad set of materials, demonstrated with nickel and alumina microcantilevers.  ...  The Young's moduli can be tuned by controlling the porosity and the deformation mode, which is dependent on the pore structure.  ...  Program (DOE SCGF), made possible in part by the American Recovery and Reinvestment Act of 2009, administered by ORISE-ORAU under contract no.  ... 
doi:10.1088/0960-1317/24/10/105006 fatcat:6aqau3ocnver3isno6yccvdceq

Low Voltage in Limb leads in Arrhythmogenic Cardiomyopathy

Stefan Peters
2021 Journal of clinical cardiology and diagnostics  
Three patients represented with low voltage in limb leads and T wave inversions in inferolateral leads characterizing arrhythmogenic left ventricular cardiomyopathy or phospholamban (PLN) cardiomyopathy  ...  In six cases low voltage in limb and precordial leads and developing complete RBBB were found. Four patients were tranplanted, two cases died due to heart failure.  ...  Left ventricular ejection fraction was in these cases between 40 and 50%.  ... 
doi:10.33309/2639-8265.040102 fatcat:h7flimnrezf27irmurezwb33nu

The rheology of aqueous emulsions prepared by direct emulsification and phase inversion from a high viscosity alkyd resin

David J Watson, Malcolm R Mackley
2002 Colloids and Surfaces A: Physicochemical and Engineering Aspects  
A comparison of the rheological properties of dispersions of an alkyd resin in water prepared by direct emulsification and phase inversion has been conducted.  ...  An experimental investigation of the effect of dispersed phase fraction, droplet size and dispersion age on the rheological properties of dispersions produced by each emulsification route has been carried  ...  Acknowledgements The authors wish to thank the EPSRC and ICI Paints, Slough, for financial support for this work.  ... 
doi:10.1016/s0927-7757(01)00813-5 fatcat:rdo5mxcxw5eyrlg36al7tq6vsu

Method R Estimates of Additive Genetic, Dominance Genetic, and Permanent Environmental Fraction of Variance for Yield and Health Traits of Holsteins

C.P. Van Tassell, I. Misztal, L. Varona
2000 Journal of Dairy Science  
Estimated additive genetic and dominance genetic fractions of variance were 0.12 and 0.06 for productive life.  ...  Mean empirical standard errors of additive genetic, dominance genetic, and permanent environmental variance fractions were 0.003, 0.006, and 0.006.  ...  By using a similar general technique, Hoeschele and Van-Raden (8) derived algorithms to obtain inverses of dominance relationship matrices.  ... 
doi:10.3168/jds.s0022-0302(00)75059-4 pmid:10984165 fatcat:fu7ghtbuqngnlp4d4qcqryvg3a

Inverse problems of determining parameters of the fractional partial differential equations [chapter]

Zhiyuan Li, Yikan Liu, Masahiro Yamamoto, Anatoly Kochubei, Yuri Luchko
2019 Fractional Differential Equations  
This chapter surveys works on such inverse problems for fractional diffusion equations.  ...  often unknown and difficult to be directly measured, which requires one to discuss inverse problems of identifying these physical quantities from some indirectly observed information of solutions.  ...  In (4), we assume the boundary condition g = 0 and we investigate inverse problems of identifying fractional orders α j and coefficients p j . Inverse Problem.  ... 
doi:10.1515/9783110571660-019 fatcat:4s6qsj2zg5d7ham56svwat6tcu

Observational Evidence That Enhanced Subsidence Reduces Subtropical Marine Boundary Layer Cloudiness

Timothy A. Myers, Joel R. Norris
2013 Journal of Climate  
Moreover, a stronger inversion reduces entrainment drying and warming, thus leading to a more humid boundary layer and greater cloud thickness, liquid water path, and cloud fraction.  ...  for the same value of inversion strength and that a stronger inversion favors greater cloudiness for the same value of subsidence.  ...  strength is the dominant contributor to climatological variability in cloud fraction.  ... 
doi:10.1175/jcli-d-12-00736.1 fatcat:vu2mbp4z7ve3lg35apsrjarlri

Page 65 of None Vol. 122, Issue 1 [page]

1961 None  
Various measurements have been made on _ polycrystalline samples, but in these samples the inhomogeneity broadening and surface scattering certainly dominate the intrinsic linewidth.  ...  Fraction of cobalt ions which contributes to linewidth as a function of degree of inversion of MeFe2O,. 187. P. Kaminow, J. Appl. Phys. 31, 220S_(1960).  ... 

The value of high-frequency, high-precision methane isotopologue measurements for source and sink estimation

M. Rigby, A. J. Manning, R. G. Prinn
2012 Journal of Geophysical Research  
We are very grateful to Shuhei Ono and Kat Potter at MIT and David Nelson and Mark Zahniser at Aerodyne Research Incorporated for their work on optical isotopologue measurements and sample preconcentration  ...  Matthew Rigby and Ron Prinn were supported, through the AGAGE research program, by the NASA Upper Atmospheric Research Program in the U.S. with grants NNX07AE89G and NNX11AF17G to MIT.  ...  Inversions were carried out using mole fraction-only and then mole fraction and isotopologue data.  ... 
doi:10.1029/2011jd017384 fatcat:2yfk63rurjg4jityokpyt6b5cm

Electron and photon energy deposition in the Universe

Toru Kanzaki, Masahiro Kawasaki
2008 Physical Review D  
We carry out detailed calculations of fractions of the initial energy of the injected electron or photon which are used to heat, ionize and excite background plasma in the early universe for various ionization  ...  states and redshifts.  ...  The fraction of heat increases as ionization fraction increases and vice versa. For larger electron energy (K e > 10 4 eV), the dominant energy loss mechanism is the inverse Compton scattering.  ... 
doi:10.1103/physrevd.78.103004 fatcat:hzt3comsszgqbkfbhhobmk72ee

Selection for recombination in partially self-fertilizing populations

D Charlesworth, B Charlesworth, C Strobeck
1979 Genetics  
Our results are based on both algebraic and computer calculations of the fate of alleles at a third locus, which control the level of recombination between the selected pair.  ...  We also show that the behavior of the population mean fitness as a function of recombination fraction is not necessarily an indicator of the direction of selection on recombination in partially selfing  ...  might have lesser effects and which might be linked or unlinked, dominant or recessive, or of intermediate dominance.  ... 
pmid:17248964 pmcid:PMC1217830 fatcat:bfxturcqv5fghf3cbspq7au7dq

Change in the protonT1of fat and water in mixture

Houchun H. Hu, Krishna S. Nayak
2010 Magnetic Resonance in Medicine  
of mixture fat fraction.  ...  In the vegetable oil-water emulsions, the T 1 of fat varied by as much as 3-fold when water was the dominant mixture component.  ...  Smith, Jr. and Timothy R.  ... 
doi:10.1002/mrm.22205 pmid:19918888 pmcid:PMC2813964 fatcat:ehz5ds7aqrbx5pm4hy4ynbjgim
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