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A physical packing sequence algorithm for the container loading problem with static mechanical equilibrium conditions

A. Galrão Ramos, José F. Oliveira, Manuel P. Lopes
2014 International Transactions in Operational Research  
The second proposed algorithm is a physical packing sequence algorithm that, given a container loading arrangement, generates the actual sequence by which each box is placed inside the container, considering  ...  The first is a static stability algorithm based on static mechanical equilibrium conditions that can be used as a stability evaluation function embedded in CLP algorithms (e.g. constructive heuristics,  ...  Acknowledgments This research was partially supported by the ERDF through the COMPETE Programme, by the Portuguese Government through the FCT (StableCargo-PTDC/SEN-TRA/121715/2010 and PTDC/EGE-GES/117692  ... 
doi:10.1111/itor.12124 fatcat:kvumgchabvbstf2vqgfe5qzvhi

Preface to the Special Issue on Cutting and Packing

A. Miguel Gomes, José Fernando Gonçalves, Ramón Alvarez-Valdés, J. Valério de Carvalho
2015 International Transactions in Operational Research  
The first paper co-authored by Vancroonenburg, Garraffa, Salassa, Vanden Berghe and Wauters presents a heuristic for a cutting problem with sequence dependent cut losses.  ...  This special issue starts with a group of three papers in the area of 1D-Cutting and sequence related problems.  ...  The tenth paper co-authored by Ramos, Oliveira and Lopes develops a physical packing sequence algorithm for the container loading problem with static mechanical equilibrium conditions.  ... 
doi:10.1111/itor.12208 fatcat:t6p3h7mgbrhmhn5waxhifrozve

A linear programming algorithm to test for jamming in hard-sphere packings

Aleksandar Donev, Salvatore Torquato, Frank H. Stillinger, Robert Connelly
2004 Journal of Computational Physics  
We have implemented the algorithms and applied them to ordered as well as random packings of circular disks and spheres with periodic boundary conditions.  ...  The algorithm is based on linear programming and is applicable to regular as well as random packings of finite size with hard-wall and periodic boundary conditions.  ...  Acknowledgements The authors thank Robert Vanderbei for numerous helpful discussions on mathematical programming issues and for providing us with the LOQO optimization library.  ... 
doi:10.1016/ fatcat:tykfdvboxbe5pmb6p7rwksr224

Mapping the stochastic response of nanostructures

S. Pattamatta, R. S. Elliott, E. B. Tadmor
2014 Proceedings of the National Academy of Sciences of the United States of America  
specified loading conditions.  ...  The end result for both static and dynamic simulations is the response trajectory, u = uðλÞ, i.e., the arrangement of the atoms as a function of the applied load.  ...  Rather than statically or dynamically generating a single response trajectory, we use branch-following and bifurcation (BFB) algorithms to generate a diagram we call the equilibrium map (EM), which contains  ... 
doi:10.1073/pnas.1402029111 pmid:24733929 pmcid:PMC4035991 fatcat:ekwagl6gq5hkrg47arbxhfshhy

A Linear Programming Algorithm to Test for Jamming in Hard-Sphere Packings [article]

Aleksandar Donev, Salvatore Torquato, Frank H. Stillinger, Robert Connelly
2002 arXiv   pre-print
The algorithm is based on linear programming and is applicable to regular as well as random packings of finite size with hard-wall and periodic boundary conditions.  ...  In this work we present a rigorous and efficient algorithm to assess whether a hard-sphere packing is jammed according to the afformentioned categories.  ...  Acknowledgments The authors would like to thank Robert Vanderbei for providing us with the LOQO optimization library.  ... 
arXiv:cond-mat/0208502v1 fatcat:74foog5dovhcbnpqmdoedlslfa

Geometric origin of mechanical properties of granular materials

Jean-Noël Roux
2000 Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics  
The approximation of small displacements (ASD) allows to draw analogies with other model systems studied in statistical mechanics, such as minimum paths on a lattice.  ...  It also entails the uniqueness of the equilibrium state (the list of contacts itself is geometrically determined) for cohesionless grains, and thus the absence of plastic dissipation.  ...  An algorithm to compute a sequence of equilibrium configurations.  ... 
doi:10.1103/physreve.61.6802 pmid:11088375 fatcat:jlve2kw6u5arhhkqunr3igegzi

Multicontact dynamics of granular systems

Farhang Radjai
1999 Computer Physics Communications  
We show that two modes of stress transmission coexist in a granular assembly, and discuss the robustness of this behavior with respect to material parameters, boundary conditions, and simulation methods  ...  The simplest example of a fully multicontact system is a granular packing in quasi-static flow or simply in static equilibrium.  ...  Interestingly, our numerical simulations show the same distribution (2) also in 3D packings with exponents α 0 and β 1.4 at static equilibrium.  ... 
doi:10.1016/s0010-4655(99)00337-9 fatcat:6n42yiparjgpnf7xbmprutktga

Microstructure evolution of compressible granular systems under large deformations

Marcial Gonzalez, Alberto M. Cuitiño
2016 Journal of the mechanics and physics of solids  
Particle-wall forces are in remarkable agreement with experimental measurements reported in the literature, providing a unifying framework for bridging experimental boundary observations with bulk behavior  ...  We report three-dimensional particle mechanics static calculations that predict the microstructure evolution during die-compaction of elastic spherical particles up to relative densities close to one.  ...  Acknowledgements The authors gratefully acknowledge the support received from the NSF ERC grant number EEC-0540855, ERC for Structured Organic Particulate Systems.  ... 
doi:10.1016/j.jmps.2016.03.024 fatcat:bedlkpslgzhb7lnqc2swybinju

Predicting orientation-dependent plastic susceptibility from static structure in amorphous solids via deep learning

Zhao Fan, Evan Ma
2021 Nature Communications  
This novel structure representation, when combined with convolutional neural network (CNN), a powerful deep learning algorithm, leads to unprecedented accuracy for identifying atoms with high propensity  ...  Our analysis of the new structure representation also provides valuable insight into key atomic packing features that influence the local mechanical response and its anisotropy in glasses.  ...  All custom codes are available from the corresponding author upon request.  ... 
doi:10.1038/s41467-021-21806-z pmid:33686082 fatcat:vhbfcspu6jd63g7vnfwecrr6yu

Logistic constraints in container loading problems: the impact of complete shipment conditions

I. Gimenez-Palacios, M. T. Alonso, R. Alvarez-Valdes, F. Parreño
2020 TOP - An Official Journal of the Spanish Society of Statistics and Operations Research  
Container loading problems (CLP), in which a set of boxes have to be loaded into containers or onto trucks, are at the core of many transportation problems.  ...  Good solutions to these packing problems are crucial for the efficient use of logistic resources.  ...  Compliance with ethical standards Conflict of interest The authors declare that they have no conflict of interest.  ... 
doi:10.1007/s11750-020-00577-8 fatcat:4nat4jlgr5eflmfssqvtf2le64

Stress in frictionless granular material: Adaptive network simulations

Alexei V. Tkachenko, Thomas A. Witten
2000 Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics  
The coefficients in the linear constraint remain nearly constant for a range of shear loadings up to about .6 of the normal loading.  ...  We start from a configuration containing cohesive (tensile) contact forces and use an adaptive procedure to find the stable configuration with no tensile contact forces.  ...  Likewise, we thank the participants in the Jamming and Rheology Program of the Institute of Theoretical Physics. This work was supported in part by the National Science Foundation under Grant Nos.  ... 
doi:10.1103/physreve.62.2510 pmid:11088731 fatcat:3mb6b2iiazgurlftmjl46xvs6q

A class of particulate problems suited to FDEM requiring accurate simulation of shape effects in packed granular structures

John-Paul Latham, J. Xiang, A. Farsi, C. Joulin, N. Karantzoulis
2019 Computational Particle Mechanics  
The clear advantages of FDEM for complex-shaped particle interactions in packed systems with relatively few particles are discussed.  ...  There are certain applications, typically involving manufactured particles, where a representative pack is of the order of a thousand particles.  ...  We are also grateful for the previous and ongoing shared interest in this technology that we have with engineers at Johnson Matthey in catalyst supports and with Baird Associates in coastal engineering  ... 
doi:10.1007/s40571-019-00294-5 fatcat:6g3xcik3svaphnhsuimt4njjk4

Underconstrained jammed packings of nonspherical hard particles: Ellipses and ellipsoids

Aleksandar Donev, Robert Connelly, Frank H. Stillinger, Salvatore Torquato
2007 Physical Review E  
We apply an algorithm using these conditions to computer-generated hypoconstrained ellipsoid and ellipse packings and demonstrate that our algorithm does produce jammed packings, even close to the sphere  ...  Finally, we consider the jamming conditions for nearly spherical particles and explain quantitatively the behavior we observe in the vicinity of the sphere point.  ...  We thank Paul Chaikin for many inspiring discussions of ellipsoid packings.  ... 
doi:10.1103/physreve.75.051304 pmid:17677051 fatcat:dtghrqdzufcl5mufuhkvaupe5m

Constrained euler buckling

G. Domokos, P. Holmes, B. Royce
1997 Journal of nonlinear science  
In contrast to the simple behavior of the unconstrained problem, we find a rich bifurcation structure, with multiple branches and concomitant hysteresis in the overall load-displacement curves.  ...  We formulate the geometrically nonlinear (Euler) problem, derive some analytical results for special cases, and develop a numerical shooting scheme for solution.  ...  This task can be completed by a path-continuation method. In structural mechanics most path-continuation algorithms are based on extrapolation along the equilibrium path.  ... 
doi:10.1007/bf02678090 fatcat:vtpybnjiwve3lf26rxwvi7zmfm

Sharing Loading Costs for Multi Compartment Vehicles

Bruce Hartman
2018 Games  
These vehicles allow better consolidation of loads. However, constructing the optimal load is a difficult problem, requiring heuristics for solution.  ...  We outline the basic structure of the MCV loading problem, and offer the view that the optimization and cost allocation problems must be solved together.  ...  Reference [4] solves a container (compartment) loading problem with sophisticated constraints for static mechanical equilibrium.  ... 
doi:10.3390/g9020025 fatcat:5u2qxsgrnfhpdhs6mvbmatay2m
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