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1. Towards a Flow- and Path-Sensitive Information Flow Analysis

   https://doi.org/10.1109/CSF.2017.17  

   Li, Peixuan; Zhang, Danfeng (August 2017, 30th IEEE Computer Security Foundations Symposium)
2. Three‐Dimensional Subsurface Flow Path Controls on Flow Permanence

   https://doi.org/10.1029/2020WR028270  

   Dohman, J. M.; Godsey, S. E.; Hale, R. L. (September 2021, Water Resources Research)

   Abstract Intermittent streams currently constitute >50% of the global river network, and the number of intermittent streams is expected to increase due to changes in land use and climate. Surface flows are known to expand and contract within the headwater channel network due to changes in the water table driven by climate, often changing seasonally. However, the underlying causes of disconnections and reconnections throughout the stream network remain poorly understood and may reflect subsurface flow capacity. We assess how 3D subsurface flowpaths control local surface flows at Gibson Jack Creek in the Rocky Mountains, Idaho, USA. Water table dynamics, hydraulic gradients, and hyporheic exchange were monitored along a 200‐m section of the stream throughout the seasonal recession in WY2018. Shallow lateral hillslope‐riparian‐stream connectivity was more frequent in transects spanning perennially flowing stream reaches than intermittent reaches. During low‐flow periods, larger losing vertical hydraulic gradients were observed in paired piezometers in intermittent reaches than in adjacent perennial reaches. Contrary to dominant conceptual models, longitudinal measurements of hydrologic exchange in both intermittent and perennial reaches were seasonally variable except for one perennial reach that showed consistent significant gains. Observed drying dynamics, as well as subsurface pathways, were highly variable even over short distances (30 m). Flow probability and subsurface flow capacity at upstream locations can be assessed with an outlet hydrograph and upstream flow measurements. Accurate characterization of subsurface storage, discharge, and connection is critical to understanding the drivers of drying cycles in intermittent streams and their likely responses to future change. 

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3. Maximum Flow and Minimum-Cost Flow in Almost-Linear Time

   https://doi.org/10.1109/FOCS54457.2022.00064  

   Chen, Li; Kyng, Rasmus; Liu, Yang P.; Peng, Richard; Gutenberg, Maximilian Probst; Sachdeva, Sushant (October 2022, 2022 IEEE 63rd Annual Symposium on Foundations of Computer Science (FOCS))

   We give an algorithm that computes exact maximum flows and minimum-cost flows on directed graphs with m edges and polynomially bounded integral demands, costs, and capacities in m^{1+o(1)} time. Our algorithm builds the flow through a sequence of m^{1+o(1)} approximate undirected minimum-ratio cycles, each of which is computed and processed in amortized m^{o(1)} time using a new dynamic graph data structure. Our framework extends to algorithms running in m^{1+o(1)} time for computing flows that minimize general edge-separable convex functions to high accuracy. This gives almost-linear time algorithms for several problems including entropy-regularized optimal transport, matrix scaling, p-norm flows, and p-norm isotonic regression on arbitrary directed acyclic graphs. 

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4. Using magma flow indicators to infer flow dynamics in sills

   https://doi.org/10.1016/j.jsg.2017.02.005  

   Hoyer, Lauren; Watkeys, Michael K. (March 2017, Journal of Structural Geology)
5. Flow topology changes with bubbly flow around a circular cylinder

   https://doi.org/10.1016/j.ijmultiphaseflow.2024.104917  

   Thacher, Eric; Van_Ruymbeke, Bruno; Gabillet, Céline; Jacques, Nicolas; Mäkiharju, Simo A (September 2024, International Journal of Multiphase Flow)

   Vortex induced vibration (VIV) experienced during flow past a cylinder can reduce equipment performance and in some cases lead to failure. Previous studies have shown that the injection of bubbles in the flow over a cylinder typically leads to a monotonic increase in shedding frequency with void fraction, however, a satisfactory explanation for this phenomenon has not been proposed. Unexplained scatter in the data exists, including that the increase in shedding frequency is not universal. More research is needed to characterize the influence of bubbles on the wake structure, and subsequent shift in shedding frequency. To this aim, the effect of bubbles on the structure of the wake and VIV was examined over two values of Reynolds number, 𝑅𝑒𝐷 = 100, 000 and 160,000. Time-resolved particle image velocimetry (TR-PIV), proper orthogonal decomposition (POD) and spectral proper orthogonal decomposition (SPOD) of the wake structures, vibration of the cylinder, and bubble image velocimetry (BIV) were used to assess the flow topology changes under the influence of gas injection. Using SPOD/POD analysis in the near wake, it was found that the primary Karman shedding frequency decreased with the injection of gas, from a Strouhal number of St = 0.2 to St = 0.17−0.18; the width of the spectral peak was found to increase with void fraction. Notably, the vibration of the cylinder at the primary Karman shedding frequency was suppressed following the injection of gas, even at spanwiseaveraged volumetric qualities below 0.01%. This suppression occurred regardless of if gas was concentrated locally near the centerline of the channel, or along the span. BIV data suggests that gas accumulation in the near wake, driven by the high velocity vertical motion of gas, serves to uncouple the cylinder motion from the formation of the vortex street downstream while promoting faster wake recovery. 

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