Instance: zuck_medium

1. Contents:
2. Information
3. File downloads
4. Solution files
   1. UPIT
   2. CPIT
   3. PCPSP
5. References

Information:

Description:

Mine provided by Mark Zuckenberg

Block model:

29277 blocks of unknown size

precedence precomputed by provider

Blockfile columns detail:

id x y z cost value rock_tonnes ore_tonnes

Blockvalue computation

precomputed by provider

Discount rate = 0.1

Type of Constraints:

C0 Capacity constraint (mine): Total extracted tonnage < 18M

C1 Capacity constraint (process): Total processed tonnage < 8M

File downloads:

• .blocks file: zuck_medium.blocks
  
• .prec file: zuck_medium.prec
• .upit file: zuck_medium.upit
• .cpit file: zuck_medium.cpit
• .pcpsp file: zuck_medium.pcpsp

Download the Minelib data format specification.

Solution files:

UPIT

Download: zuck_medium_upit.sol

Objective value: 1,075,124,490

Computed using Hochbaum's pseudoflow algorithm. [*]

CPIT

Download: zuck_medium_cpit_gmunoz120723.sol

Objective value: 615,411,415 (LP GAP 13.4%)

Provided by Gonzalo Muñoz, and obtained from the LP relaxation using a modified TopoSort heuristic. [*]

Download: zuck_medium.LPcpit

LP relaxation solution (not feasible)

Objective value: 710,641,410

Computed using a modified version of Bienstock & Zuckerberg algorithm. [*]

PCPSP

Download: zuck_medium_pcpsp_gmunoz120723.sol

Objective value: 675,931,038 (LP GAP 9.9%)

Provided by Gonzalo Muñoz, and obtained from the LP relaxation using a modified TopoSort heuristic.[*]

Download: zuck_medium.LPpcpsp

LP relaxation solution (not feasible)

Objective value: 750,519,109

Computed using a modified version of Bienstock & Zuckerberg algorithm.[*]

References:

• Daniel Bienstock, Mark Zuckerberg (2010), Solving LP Relaxations of Large-Scale Precedence Constrained Problems. IPCO 2010: 1-14
• Dorit S. Hochbaum (2008), The Pseudoflow Algorithm: A New Algorithm for the Maximum-Flow Problem. Operations Research 56(4): 992-1009
  
• Gonzalo Muñoz (2012), Modelos de optimizacion lineal entera y aplicaciones a la mineria. Master thesis, Dept. Mathematical Engineering, Universidad de Chile.