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Uncertainty Visualization of Transport Variance in a Time-Varying Ensemble Vector Field

Ke Ren, Dezhan Qu, Shaobin Xu, Xufeng Jiao, Liang Tai, Huijie Zhang
2020 ISPRS International Journal of Geo-Information  
Uncertainty analysis of a time-varying ensemble vector field is a challenging topic in geoscience.  ...  Due to the complex data structure, the uncertainty of a time-varying ensemble vector field is hard to quantify and analyze.  ...  A comprehensive visual analysis system for exploring the uncertainty in a time-varying ensemble vector field.  ... 
doi:10.3390/ijgi9010019 fatcat:nemfjvdhsfdihdckpirk67fyfy

Comparative Visual Analysis of Lagrangian Transport in CFD Ensembles

Mathias Hummel, Harald Obermaier, Christoph Garth, Kenneth I. Joy
2013 IEEE Transactions on Visualization and Computer Graphics  
For ensembles of time-varying vector fields, there are numerous challenges for providing an expressive comparative visualization, among which is the requirement to relate the effect of individual flow  ...  Yet, techniques developed for scalar ensembles are of little use in this context, as the notion of transport induced by a vector field cannot be modeled using such tools.  ...  ACKNOWLEDGMENTS This work was supported in part by the NSF (IIS 0916289 and IIS 1018097), and the Office of ASCR, Office of Science, through DOE SciDAC contract DE-FC02-06ER25780, and contract DE-FC02-  ... 
doi:10.1109/tvcg.2013.141 pmid:24051841 fatcat:ro6r3krzb5fxrdyybqfeuxzu5a

Uncertain Transport in Unsteady Flows [article]

Tobias Rapp, Carsten Dachsbacher
2020 arXiv   pre-print
We study uncertainty in the dynamics of time-dependent flows by identifying barriers and enhancers to stochastic transport.  ...  In addition, we propose a complementary visualization to convey the absolute scale of uncertainties in the Lagrangian frame of reference.  ...  Although it is possible to directly visualize the time-dependent variance of a Gaussian flow field, we are interested in the uncertainty of the transport, which is inherently defined in a Lagrangian frame  ... 
arXiv:2009.04531v1 fatcat:zevtebbptrgjvitf2tkvzouona

User-defined feature comparison for vector field ensembles

Richen Liu, Hanqi Guo, Xiaoru Yuan
2016 Journal of Visualization  
Most of the existing approaches to visualize the vector field ensembles are to reveal the uncertainty of individual variables, for example, statistics, variability etc.  ...  In this paper, we present a new framework to extract user-defined derived features from different simulation runs.  ...  Most high values of joint variance are expected in regions with strongly varying transport behavior across ensemble runs.  ... 
doi:10.1007/s12650-016-0388-0 fatcat:m2swqa6rb5fqbmqbklhpm4afgq

Statistical Rendering for Visualization of Red Sea Eddy Simulation Data [article]

Tushar M. Athawale, Alireza Entezari, Bei Wang, Chris R. Johnson
2021 arXiv   pre-print
Specifically, we demonstrate the applications of statistical volume rendering and statistical Morse complex summary maps to a velocity magnitude field for studying the eddy positions in the flow dataset  ...  We present an application of statistical visualization algorithms for the analysis of the Red Sea eddy simulation ensemble.  ...  Each ensemble is sampled on a domain with a grid of resolution 500 × 500 × 50, and ensembles are sampled for 60 time steps to represent a time-varying 3D flow [9] .  ... 
arXiv:2106.12138v1 fatcat:p357ejrx55dzzjjbd5eg2ay2ra

Comparative visualization of vector field ensembles based on longest common subsequence

Richen Liu, Hanqi Guo, Jiang Zhang, Xiaoru Yuan
2016 2016 IEEE Pacific Visualization Symposium (PacificVis)  
We propose a longest common subsequence (LCSS)-based approach to compute the distance among vector field ensembles.  ...  By measuring how many common blocks the ensemble pathlines pass through, the LCSS distance defines the similarity among vector field ensembles by counting the number of shared domain data blocks.  ...  Most high values of joint variance are expected in regions with strongly varying transport behavior across the runs of the ensemble.  ... 
doi:10.1109/pacificvis.2016.7465256 dblp:conf/apvis/LiuGZY16 fatcat:munk6bprknaxfill6qtjnwxi6i

An Image-based Ensemble Kalman Filter for Motion Estimation

Yann Lepoittevin, Isabelle Herlin, Dominique Béréziat
2015 Proceedings of the 10th International Conference on Computer Vision Theory and Applications  
The initial ensemble is obtained by adding a Gaussian vector field to an estimate of motion on the first two frames.  ...  The propagation in time of the ensemble members relies on the following evolution laws: transport by velocity of the image brightness function and Euler equations for the motion function.  ...  An ensemble of background state vectors X (b), j k is defined at each time index k. It samples the uncertainty co- variance matrix B (b) k .  ... 
doi:10.5220/0005259804370445 dblp:conf/visapp/LepoittevinHB15 fatcat:47ezbhvutnfwvf644jvuvzgxpm

Impacts of Sea Surface Temperature Uncertainty on the Western North Pacific Subtropical High (WNPSH) and Rainfall

Xiaodong Hong, Craig H. Bishop, Teddy Holt, Larry O'Neill
2011 Weather and forecasting  
This, in turn, increases the variance of the low-level jet (LLJ) over southeast China, resulting in large differences in the moist transport flux from the tropical ocean and subsequent rainfall.  ...  Scatter diagram of the bin-mean ensemble variance and bin-mean squared error for 48-h forecasts of the (a) sea level pressure, (b) 2-m air temperature, (c) u-wind component, and (d) y-wind component.  ...  The support of the sponsor, the Space and Naval Warfare System Command (SPAWAR), through Program Element 75927210, is gratefully acknowledged.  ... 
doi:10.1175/waf-d-10-05007.1 fatcat:jtuylrp67vcn7n7eic2ja56qs4

A bottom-up scheme for user-defined feature comparison in ensemble data

Richen Liu, Hanqi Guo, Xiaoru Yuan
2015 SIGGRAPH Asia 2015 Visualization in High Performance Computing on - SA '15  
Most of the existing approaches to visualizing the vector field ensembles are achieved by visualizing the uncertainty of individual variables of different simulation runs, for example, geometry distance  ...  Recently, there are some line-based methods to effectively detect the vortex lines in vector field. A sketch-based approach [Wei et al. 2010 ] allows the user to sketch a 2D curve as template.  ...  The visualization of ensemble pathlines advected in the ensemble vector fields can reveal the characteristic feature of the simulation.  ... 
doi:10.1145/2818517.2818531 dblp:conf/siggraph/LiuGY15 fatcat:7cemhxp7ungrxjlb4khypo3eta

Multi-space analysis techniques for spatio-temporal simulation data visualization: A survey

Xueyi Chen, Liming Shen, Ziqi Sha, Richen Liu, Siming Chen, Genlin Ji, Chao Tan
2019 Visual Informatics  
The widespread use of numerical simulations in different scientific domains provides a variety of research opportunities.  ...  However, it lacks a survey to have a systematic overview of the essential commonalities shared by those works.  ...  Acknowledgment This work was supported by the National Natural Science Foundation of China (NSFC) Grant Nos. 61702271 and 61702270.  ... 
doi:10.1016/j.visinf.2019.08.002 fatcat:g3sftl24avctbjdsk3cmctt5be

Characterization of non-Gaussian conductivities and porosities with hydraulic heads, solute concentrations, and water temperatures

Teng Xu, J. Jaime Gómez-Hernández
2016 Water Resources Research  
Reliable characterization of hydraulic parameters is important for the understanding of groundwater flow and solute transport.  ...  A synthetic example including seven tests is designed, and used to evaluate the ability to characterize hydraulic conductivity and porosity in a non-Gaussian setting by assimilating different numbers and  ...  All data used in this analysis are available from the authors. Water Resources Research 10.1002/2016WR019011  ... 
doi:10.1002/2016wr019011 fatcat:y4gfzzqafzbn7l5f25ouvncruu

Uncertainty assessment and data worth in groundwater flow and mass transport modeling using a blocking Markov chain Monte Carlo method

Jianlin Fu, J. Jaime Gómez-Hernández
2009 Journal of Hydrology  
The second author had a sabbatical grant by Technical University of Valencia during the preparation of this manuscript.  ...  Acknowledgements 25 A doctoral fellowship and an extra travel grant awarded to the first author by the Universitat Politècnica de València, Spain, is gratefully acknowledged.  ...  78 Ensemble variance of piezometric head fields for the different scenarios spreading in the longitudinal direction.  ... 
doi:10.1016/j.jhydrol.2008.11.014 fatcat:hfvdjbxsr5cnhccvoi2kklbrp4

Visualizing the Variability of Gradients in Uncertain 2D Scalar Fields

Tobias Pfaffelmoser, Mihaela Mihai, Rudiger Westermann
2013 IEEE Transactions on Visualization and Computer Graphics  
In uncertain scalar fields where data values vary with a certain probability, the strength of this variability indicates the confidence in the data.  ...  While this framework generalizes to 3D uncertain scalar fields, we concentrate on the visualization of the resulting intervals in 2D fields.  ...  In a third example, we use uncertainty visualization to identify stable features in the mean values of an ensemble of temperature fields.  ... 
doi:10.1109/tvcg.2013.92 pmid:24029913 fatcat:md7lfwoefnf4ppjvzplk2hmrdi

Accounting for Transport Error in Inversions: An Urban Synthetic Data Experiment

Subhomoy Ghosh, Kimberly Mueller, Kuldeep Prasad, James Whetstone
2021 Earth and Space Science  
This research was supported by the National Institute of Standards and Technology's Green House Gas Measurement Program (University of Notre Dame, #70NANB19H132).  ...  Acknowledgments The authors thank Israel Lopez-Coto from National Institute of Standards and technology (NIST) for providing the influence functions and the prior emission inventory; Adam Pinter, Anna  ...  of transport uncertainty.  ... 
doi:10.1029/2020ea001272 fatcat:slmrd6skw5fhxjchm55y6ytwve

Comparison of Two Ensemble Kalman-Based Methods for Estimating Aquifer Parameters from Virtual 2-D Hydraulic and Tracer Tomographic Tests

Emilio Sánchez-León, Daniel Erdal, Carsten Leven, Olaf A. Cirpka
2020 Geosciences  
For hydraulic data, we use the standard update scheme of the EnKF with damping, whereas for concentration data, we apply a restart scheme, in which solute transport is resimulated from time zero to the  ...  We compare two ensemble Kalman-based methods to estimate the hydraulic conductivity field of an aquifer from data of hydraulic and tracer tomographic experiments: (i) the Ensemble Kalman Filter (EnKF)  ...  To facilitate a visual comparison of the parameter fields estimated by both methods, Figure 6 also displays the ensemble-mean of log-hydraulic conductivity and associated variance, obtained after all  ... 
doi:10.3390/geosciences10070276 fatcat:jgifwgqvfnggrm3ol2em27tvwy
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