This paper presents a bottleneck-based methodology to solve scheduling problem of M1,M2,M3,M4,M3,M4 re-entrant flow shop where M1 and M4 have high tendency of being the dominant machines. Two generalised makespan algorithms using bottleneck approach were developed for the identified bottleneck. Each algorithm has specific correction factor which was used to ensure the accuracy of the makespan c...

We consider the robust surgery loading problem for a hospital's operating theatre department, which concerns assigning surgeries and sufficient planned slack to operating room days. The objective is to maximize capacity utilization and minimize the risk of overtime, and thus cancelled patients. We propose various constructive heuristics and local search methods that use statistical information ...

The Stochastic Eulerian Tour Problem (SETP) seeks the Eulerian tour of minimum expected length on an undirected Eulerian graph, when demand on the arcs that have to be serviced is probabilistic. In an earlier paper, we have shown that the SETP is NP-hard and derived several properties of the optimal tour. In this paper, we develop three constructive heuristics for the SETP. The first two are gr...

This paper presents a new heuristic named GAPH based on a structural property for minimizing makespan in no-wait flowshop with sequence-dependent setup times. Experimental results demonstrate the superiority of the proposed approach over thhree of the best-know methods in the literature. Experimental and statistical analyses show that the new heuristic provides better solutions regarding the so...

This work presents optimisation models to support decisions in the production planning and control of the electrofused grain industry. A case study was carried out in a Brazilian company with the aim of helping to increase productivity and improve customer service concerning meeting deadlines. Mixed integer linear programming models combining known models of process selection and single-stage l...

We consider the problem of partitioning a set of positive integers values into a given number of subsets, each having an associated cardinality limit, so that the maximum sum of values in a subset is minimized, and the number of values in each subset does not exceed the corresponding limit. The problem is related to scheduling and bin packing problems. We give combinatorial lower bounds, reduct...

The technician routing and scheduling problem consists in routing and scheduling a crew of technicians in order to attend a set of service requests, subject to skill, tool, and spare part constraints. In this study we propose a formal definition of the problem and present a constructive heuristic and a large neighborhood search optimization algorithm.

This paper deals with the Set Covering with Pairs Problem (SCPP). This problem is a generalization of the Set Covering Problem (SCP), which is known to be NP-hard. The difference between both problems is that, in the SCPP, one element of the universe is admitted to be covered if there are at least two specific objects chosen to cover it. In this context, three constructive heuristics, one local...

Examination timetabling has been a widely studied research problem for over 30 years, with many techniques being used to produce good quality solutions. The majority of the techniques rely on producing an initial solution using a constructive heuristic, and then improving it via a local search [1,2,3], relying on the correct setting of internal parameters to allow generally acceptable results f...

This paper presents a very special cutting path determination problem appearing in a high precision tools factory, and provides two new heuristics for its resolution. Particular features of both the cutting process, and of the material to be cut, bring in a set of unusual constraints, when compared with other cutting processes, which confer additional complexity and originality to the problem. ...