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In this article we consider a certain sub class of Integer Equal Flow problem, which are known NP hard [8]. Currently there exist no direct solutions for the same. It is a common problem in various inventory management systems. Here we…

Artificial Intelligence · Computer Science 2019-12-11 Sasikanth Goteti , Swapnil Kumar

An important objective in scheduling literature is to minimize the sum of weighted flow times. We are given a set of jobs where each job is characterized by a release time, a processing time, and a weight. Our goal is to find a preemptive…

Data Structures and Algorithms · Computer Science 2022-08-08 Alexander Armbruster , Lars Rohwedder , Andreas Wiese

Simulating the interaction of fluids with immersed moving solids is playing an important role for gaining a better quantitative understanding of how fluid dynamics is altered by the presence of obstacles and which forces are exerted on the…

We give an algorithm for computing exact maximum flows on graphs with $m$ edges and integer capacities in the range $[1, U]$ in $\widetilde{O}(m^{\frac{3}{2} - \frac{1}{328}} \log U)$ time. For sparse graphs with polynomially bounded…

Data Structures and Algorithms · Computer Science 2021-06-11 Yu Gao , Yang P. Liu , Richard Peng

The speed of sound in two-phase pipe flow systems is often several orders of magnitude greater than the travelling speed of hydraulic information (volume fractions.) Dynamically simulating such flows requires resolution of acoustic and…

Computational Physics · Physics 2018-11-30 Andreas Holm Akselsen

We consider the planar dynamic convex hull problem. In the literature, solutions exist supporting the insertion and deletion of points in poly-logarithmic time and various queries on the convex hull of the current set of points in…

Computational Geometry · Computer Science 2024-03-12 Bruce Brewer , Gerth Stølting Brodal , Haitao Wang

We present improved deterministic algorithms for approximating shortest paths in the Congested Clique model of distributed computing. We obtain $poly(\log\log n)$-round algorithms for the following problems in unweighted undirected…

Data Structures and Algorithms · Computer Science 2020-03-09 Michal Dory , Merav Parter

One issue limiting the adaption of large-scale multi-region segmentation is the sometimes prohibitive memory requirements. This is especially troubling considering advances in massively parallel computing and commercial graphics processing…

Computer Vision and Pattern Recognition · Computer Science 2015-02-02 John S. H. Baxter , Martin Rajchl , Jing Yuan , Terry M. Peters

Many applications of computational fluid dynamics require multiple simulations of a flow under different input conditions. In this paper, a numerical algorithm is developed to efficiently determine a set of such simulations in which the…

Numerical Analysis · Mathematics 2017-05-29 Max Gunzburger , Nan Jiang , Zhu Wang

Examples of dynamical systems proposed by Z. Artstein and C. M. Dafermos admit non-unique solutions that track a one parameter family of closed circular orbits contiguous at a single point. Switching between orbits at this single point…

Analysis of PDEs · Mathematics 2024-06-03 Heiko Gimperlein , Michael Grinfeld , Robin J. Knops , Marshall Slemrod

We study the minimum-concave-cost flow problem on a two-dimensional grid. We characterize the computational complexity of this problem based on the number of rows and columns of the grid, the number of different capacities over all arcs,…

Data Structures and Algorithms · Computer Science 2016-03-01 Shabbir Ahmed , Qie He , Shi Li , George Nemhauser

Physics-informed neural networks (PINNs) employed in fluid mechanics deal primarily with stationary boundaries. This hinders the capability to address a wide range of flow problems involving moving bodies. To this end, we propose a novel…

Fluid Dynamics · Physics 2025-08-05 Yongzheng Zhu , Weizhen Kong , Jian Deng , Xin Bian

Minimum flow decomposition (MFD) is the NP-hard problem of finding a smallest decomposition of a network flow/circulation $X$ on a directed graph $G$ into weighted source-to-sink paths whose superposition equals $X$. We show that, for…

Data Structures and Algorithms · Computer Science 2023-05-11 Manuel Cáceres , Massimo Cairo , Andreas Grigorjew , Shahbaz Khan , Brendan Mumey , Romeo Rizzi , Alexandru I. Tomescu , Lucia Williams

Minimum flow decomposition (MFD) (the problem of finding a minimum set of paths that perfectly decomposes a flow) is a classical problem in Computer Science, and variants of it are powerful models in multiassembly problems in Bioinformatics…

Genomics · Quantitative Biology 2022-05-31 Fernando H. C. Dias , Lucia Williams , Brendan Mumey , Alexandru I. Tomescu

We consider some flow-time minimization problems in the unrelated machines setting. In this setting, there is a set of $m$ machines and a set of $n$ jobs, and each job $j$ has a machine dependent processing time of $p_{ij}$ on machine $i$.…

Data Structures and Algorithms · Computer Science 2015-06-11 Nikhil Bansal , Janardhan Kulkarni

An improved fully polynomial-time approximation scheme and a greedy heuristic for the fractional length-bounded maximum multicommodity flow problem with unit edge-lengths are proposed. Computational experiments are carried out on benchmark…

Data Structures and Algorithms · Computer Science 2017-08-03 Pavel Borisovsky , Anton Eremeev , Sergei Hrushev , Vadim Teplyakov , Mikhail Vorozhtsov

We investigate the performance of the finite volume method in solving viscoplastic flows. The creeping square lid-driven cavity flow of a Bingham plastic is chosen as the test case and the constitutive equation is regularised as proposed by…

Computational Physics · Physics 2016-04-29 Alexandros Syrakos , Georgios C. Georgiou , Andreas N. Alexandrou

This paper bridges discrete and continuous optimization approaches for decomposable submodular function minimization, in both the standard and parametric settings. We provide improved running times for this problem by reducing it to a…

Data Structures and Algorithms · Computer Science 2021-03-08 Kyriakos Axiotis , Adam Karczmarz , Anish Mukherjee , Piotr Sankowski , Adrian Vladu

Densest Subgraph Problem (DSP) is an important primitive problem with a wide range of applications, including fraud detection, community detection and DNA motif discovery. Edge-based density is one of the most common metrics in DSP.…

Databases · Computer Science 2023-10-31 Yugao Zhu , Shenghua Liu , Wenjie Feng , Xueqi Cheng

We propose an algorithm for solving the time-dependent shortest path problem in flow fields where the FIFO (first-in-first-out) assumption is violated. This problem variant is important for autonomous vehicles in the ocean, for example,…

Robotics · Computer Science 2019-09-06 James Ju Heon Lee , Chanyeol Yoo , Stuart Anstee , Robert Fitch