Instance: kd

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

Information:

Description:

Arizona’s Copper Deposit (KD)

Block model:

Blocks dimension: 20x20x15 m

Precedence computed with 45 degrees using 8 levels

Destinations: 1=ore, 2=waste

Blockfile columns detail:

<id> <x> <y> <z> <tonn> <blockvalue> <destination> <CU %> <process_profit>

Blockvalue computation

Profit computed using mininig cost = -0.75 per ton.
(i.e., blockvalue = -0.75 * tonn + process_profit)

Discount rate = 0.15

Type of Constraints:

Process capacity of 10M tons/year and unlimited mining capacity.

File downloads:

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

Download the Minelib data format specification.

Solution files:

UPIT

Download: kd_upit.sol

Objective value: 652,195,037

Computed using Hochbaum's pseudoflow algorithm. [*]

CPIT

Download: kd_cpit_gmunoz120723.sol

Objective value: 396,858,193 (LP GAP 3.1%)

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

Download: kd.LPcpit

LP relaxation solution (not feasible)

Objective value: 409,498,555

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

PCPSP

Download: kd_pcpsp_gmunoz120723.sol

Objective value: 406,871,207 (LP GAP 1.0%)

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

Download: kd.LPpcpsp

LP relaxation solution (not feasible)

Objective value: 410,891,003

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.