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Narrow sieves for parameterized paths and packings

Andreas Björklund, Thore Husfeldt, Petteri Kaski, Mikko Koivisto
2017 Journal of computer and system sciences (Print)  
We present parameterized algorithms for the k-path problem, the p-packing of q-sets problem, and the q-dimensional p-matching problem.  ...  The constant bases of the exponentials are significantly smaller than in previous works; for example, for the k-path problem the improvement is from 2 to 1.66.  ...  A Projection-Determinant Sieve for p-Packings of q-Sets This section establishes Theorems 2 and 4.  ... 
doi:10.1016/j.jcss.2017.03.003 fatcat:7qbt4a6ulzcf3imthpm4qolg6q

Narrow sieves for parameterized paths and packings [article]

Andreas Björklund, Thore Husfeldt, Petteri Kaski, Mikko Koivisto
2010 arXiv   pre-print
We present randomized algorithms for some well-studied, hard combinatorial problems: the k-path problem, the p-packing of q-sets problem, and the q-dimensional p-matching problem.  ...  For example, for the k-path problem the improvement is from 2 to 1.66.  ...  A Projection Sieve for k-Paths This section establishes Theorem 1. 2.1. Overview. In this section, we develop an inclusion-exclusion sieve over multivariate polynomials for the k-path problem.  ... 
arXiv:1007.1161v1 fatcat:sekbvppwsbgojennke6gqpasqi

Mixing Color Coding-Related Techniques [chapter]

Meirav Zehavi
2015 Lecture Notes in Computer Science  
. • Mixing narrow sieves and representative sets, two independent color coding-related techniques. • For certain "disjointness conditions", improving the best known computation of representative sets.  ...  We then present a unified approach to improve the O * running times of the previous best deterministic algorithms for the classic k-Path, k-Tree, r-Dimensional k-Matching and Graph Motif problems, including  ...  The fastest FPT algorithms, however, are developed using narrow sieves.  ... 
doi:10.1007/978-3-662-48350-3_86 fatcat:733vmaxxynhjfkghj6imwnpwhq

Mixing Color Coding-Related Techniques [article]

Meirav Zehavi
2015 arXiv   pre-print
Narrow sieves, representative sets and divide-and-color are three breakthrough color coding-related techniques, which led to the design of extremely fast parameterized algorithms.  ...  best deterministic algorithms for k-Path, k-Tree, r-Dimensional k-Matching, Graph Motif and Partial Cover.  ...  .: Deterministic parameterized algorithms for matching and packing problems.  ... 
arXiv:1410.5062v3 fatcat:6se2mu7tkjbylmmtt5ajuwpruu

Automating the Choice of Consistency Levels in Replicated Systems

Cheng Li, João Leitão, Allen Clement, Nuno M. Preguiça, Rodrigo Rodrigues, Viktor Vafeiadis
2014 USENIX Annual Technical Conference  
We evaluate SIEVE on two web applications and show that the automatic classification overhead is low.  ...  Taking as input a set of applicationspecific invariants and a few annotations about merge semantics, SIEVE performs a combination of static and dynamic analysis, offline and at runtime, to determine when  ...  for his assistance with Jahob.  ... 
dblp:conf/usenix/0001LCPRV14 fatcat:kamynjqsuzethfxqxefdqooote

Designing Deterministic Polynomial-Space Algorithms by Color-Coding Multivariate Polynomials [article]

Gregory Gutin, Felix Reidl, Magnus Wahlström, Meirav Zehavi
2017 arXiv   pre-print
Polynomial-space O^*((2e)^k+o(k))-time (exponential-space O^*(4.32^k)-time) algorithm for k-Colorful Out-Branching on arc-colored digraphs and k-Colorful Perfect Matching on planar edge-colored graphs.  ...  In recent years, several powerful techniques have been developed to design randomized polynomial-space parameterized algorithms.  ...  We thank Saket Saurabh for helpful information concerning splitters.  ... 
arXiv:1706.03698v2 fatcat:finoocq3yndf5i74r7xwfjeamm

Free-volume correlations in positron-sensitive annihilation modes in chalcogenide vitreous semiconductors: on the path from illusions towards realistic physical description

O.I. Shpotyuk
2014 Semiconductor Physics, Quantum Electronics & Optoelectronics  
form 1 50 . 5 2 sin 2 2 τ is proved to account for compositional trends in void volume evolution of chalcogenide semiconductor compounds like binary As-S(Se) glasses.  ...  A newly modified correlation equation between defect-related positron lifetime  2 (ns) defined within two-state model and corresponding radius R (Å ) of freevolume positron traps in the full non-linear  ...  fields proper to denser atomic packing.  ... 
doi:10.15407/spqeo17.03.243 fatcat:av4qg6lccbhmhgrsnxbphsbpey

Detecting and Counting Small Subgraphs, and Evaluating a Parameterized Tutte Polynomial: Lower Bounds via Toroidal Grids and Cayley Graph Expanders [article]

Marc Roth, Johannes Schmitt, Philip Wellnitz
2021 arXiv   pre-print
Specifically, we study the parameterized complexity of 𝙴𝚍𝚐𝚎𝚂𝚞𝚋(Φ) and of its counting problem #𝙴𝚍𝚐𝚎𝚂𝚞𝚋(Φ) with respect to both approximate and exact counting.  ...  For exact counting, we present an exhaustive and explicit criterion on the property Φ which, if satisfied, yields fixed-parameter tractability and otherwise #𝖶[1]-hardness.  ...  We thank Johannes Lengler and Holger Dell for helpful discussions on early drafts of this work.  ... 
arXiv:2011.03433v2 fatcat:7aauf7xejvfx5atw3n7s6sefsa

Physical Pore Properties and Grain Interactions of SAX04 Sands

Allen H. Reed, Karsten E. Thompson, Kevin B. Briggs, Clinton S. Willson
2010 IEEE Journal of Oceanic Engineering  
The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and  ...  , Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302.  ...  The algorithm used here gives correct permeability values for packings of uniform-sized spheres and for computer generated packings.  ... 
doi:10.1109/joe.2010.2040656 fatcat:zckuwrogzbf75nxo62xxwh4hzy

Estimating the modal mineralogy of eucrite and diogenite meteorites using visible-near infrared reflectance spectroscopy

Shuai Li, Ralph E. Milliken
2015 Meteoritics and Planetary Science  
The models were tested and compared for laboratory-made binary (pyroxene-plagioclase) and ternary mixtures (pyroxene-olivineplagioclase) as well as eucrite and diogenite meteorite samples.  ...  Radiative transfer models can be employed to accommodate these issues, and here we assess the utility of such models to accurately and efficiently determine modal mineralogy for a suite of eucrite and  ...  Paul Lucey and Dr. Ted Roush for their fruitful comments and discussion on this manuscript. We also gratefully thank Dr.  ... 
doi:10.1111/maps.12513 fatcat:qph5sact5vgiffquairgwlpw44

The Penetration of Solar Radiation into Granular Carbon Dioxide and Water Ices of Varying Grain Sizes on Mars

H.E. Chinnery, A. Hagermann, E. Kaufmann, S.R. Lewis
2020 Journal of Geophysical Research - Planets  
The e-folding scale of snow and slab ice has been previously measured, but understanding the behavior between these end-member states is important for modeling the thermal behavior and surface processes  ...  The penetration depth of broad spectrum solar irradiation over the wavelength range 300-1,100 nm has been experimentally measured for water and carbon dioxide ices of different grain size ranges.  ...  Acknowledgments The authors would like to thank the reviewers for their comments and suggestions, which have greatly improved this manuscript.  ... 
doi:10.1029/2019je006097 fatcat:c5mva3tc7nhtdf7pqxwrlaqrwm

An experimental scaling law for particle-size segregation in dense granular flows

T. Trewhela, C. Ancey, J.M.N.T. Gray
2021 Journal of Fluid Mechanics  
Despite the sometimes markedly different time scales for segregation in these two situations, a unifying scaling law has been found that is able to collapse all the experimental data over a wide range  ...  The resulting functional form is easily generalizable to intermediate concentrations and can quantitatively capture laboratory experiments and numerical simulations with a 50 : 50 mix of large and small  ...  The authors would like to thank B. de Graffenried for designing and building the new experimental shear cell, as well as for taking some of the photographs in this paper.  ... 
doi:10.1017/jfm.2021.227 fatcat:nnphg7wzvnhtpgfzs2roxkdvzu

The Interface of Nanoscale Inclusion Chemistry [chapter]

Galen D. Stucky
2007 Progress in Inorganic Chemistry  
), and the Division of Materials Research, Du Pont, and the Office of Naval Research are greatly appreciated.  ...  support of the author's wife, Kaaren, during the writing of this chapter, and funding from the National Science Foundation through the Quantized Electronic Structures Science and Technology Center (QUEST  ...  Taylor and Henderson (176) parameterized this nicely in terms of the unit cell dimensions and framework atom tetrahedral tilt angle.  ... 
doi:10.1002/9780470166413.ch2 fatcat:ippn4gvjcnh47lxc6dxnuk32ju

Evaluation of factors affecting accurate measurements of atmospheric CO2 and CH4 by wavelength-scanned cavity ring-down spectroscopy

H. Nara, H. Tanimoto, Y. Tohjima, H. Mukai, Y. Nojiri, K. Katsumata, C. Rella
2012 Atmospheric Measurement Techniques Discussions  
CO 2 and < 0.4 %V for CH 4 ).  ...  The PBEs were negligible (up to 0.05 ppm for CO 2 and 10 0.01 ppb for CH 4 ) for gas standards balanced with purified air, although the PBEs were substantial (up to 0.87 ppm for CO 2 and 1.4 ppb for CH  ...  Machida for his logistical support of our experiments. We are grateful to Y. Takahashi for CO 2 isotopic analysis. We also thank Y. Morino for valuable comments on our study.  ... 
doi:10.5194/amtd-5-5009-2012 fatcat:t47e7x5utneergyws643hh2mrm

Blowing Off Steam: Tuffisite Formation As a Regulator for Lava Dome Eruptions

Jackie E. Kendrick, Yan Lavallée, Nick R. Varley, Fabian B. Wadsworth, Oliver D. Lamb, Jérémie Vasseur
2016 Frontiers in Earth Science  
To investigate tuffisite formation we crushed and sieved andesite from the lava dome and sintered it at magmatic temperatures for different times.  ...  The natural tuffisites are more permeable than the host andesite, and have a wide range of porosity and permeability compared to a narrower window for the host rock, and gaging from their significant distribution  ...  Reyes-Dávila and RESCO for the seismic data and W. Hutchison for the use of dome volume estimates. Thanks are due to all CIIV volunteers who manually classified the seismic events.  ... 
doi:10.3389/feart.2016.00041 fatcat:bn4ixww2zjh6xpd6zgqq52oseq
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