A Lagrangian-based heuristic for large-scale set covering problems

نویسندگان

  • Sebastián Ceria
  • Paolo Nobili
  • Antonio Sassano
چکیده

We present a new Lagrangian-based heuristic for solving large-scale set-covering problems arising from crew-scheduling at the Italian Railways (Ferrovie dello Stato). Our heuristic obtained impressive results when compared to state of the art codes on a test-bed provided by the company, which includes instances with sizes ranging from 50,000 variables and 500 constraints to 1,000,000 variables and 5,000 constraints. 3.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Heuristic and exact algorithms for Generalized Bin Covering Problem

In this paper, we study the Generalized Bin Covering problem. For this problem an exact algorithm is introduced which can nd optimal solution for small scale instances. To nd a solution near optimal for large scale instances, a heuristic algorithm has been proposed. By computational experiments, the eciency of the heuristic algorithm is assessed.

متن کامل

Two new heuristic algorithms for Covering Tour Problem

Covering Tour Problem (CTP) is the generalized form of Traveling Salesman Problem (TSP), which has found different applications in the designing of distribution networks, disaster relief, and transportation routing. The purpose of this problem is to determine the Hamiltoniancyclewiththe lowest costusinga subset of all the nodes, such that the other nodes would be in a distance shorter than the ...

متن کامل

Multiship Crane Sequencing with Yard Congestion Constraints

Crane sequencing in container terminals determines the order of ship discharging and loading jobs that quay cranes (QCs) perform so that the duration of vessels’ stay is minimized. The ship’s load profile, berthing time, number of available bays and QCs are considered. More importantly, clearance and yard congestion constraints need to be included, which respectively ensure that a minimum dista...

متن کامل

A 3-flip neighborhood local search for the set covering problem

The set covering problem (SCP) asks to choose a minimum cost family of subsets from given n subsets, which together covers the entire ground set. In this paper, we propose a local search algorithm for SCP, which have the following three features. (1) The use of 3ip neighborhood, which is the set of solutions obtainable from the current solution by exchanging at most three subsets. As the size o...

متن کامل

Heuristic approach to solve hybrid flow shop scheduling problem with unrelated parallel machines

In hybrid flow shop scheduling problem (HFS) with unrelated parallel machines, a set of n jobs are processed on k machines. A mixed integer linear programming (MILP) model for the HFS scheduling problems with unrelated parallel machines has been proposed to minimize the maximum completion time (makespan). Since the problem is shown to be NP-complete, it is necessary to use heuristic methods to ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Math. Program.

دوره 81  شماره 

صفحات  -

تاریخ انتشار 1998