A rescheduling algorithm for trains on a single-track railway was developed in case of disturbances that would cause conflicts between trains. This is based mixed integer linear programming (MILP) with speed-up routines. The model considers station capacities explicitly (i.e., the number available tracks meeting and overtaking operations). Because too hard solvers (CPLEX this study) to tackle, ...

Mixed-integer quadratic programming (MIQP) is the problem of optimizing a quadratic function over points in a polyhedral set where some of the components are restricted to be integral. In this paper, we prove that the decision version of mixed-integer quadratic programming is in NP, thereby showing that it is NP-complete. This is established by showing that if the decision version of mixed-inte...

This paper presents a novel, multi-objective model of a parallel machines scheduling problem that minimizes the number of tardy jobs and total completion time of all jobs. In this model, machines are considered as unrelated parallel units with different speeds. In addition, there is some precedence, relating the jobs with non-identical due dates and their ready times. Sequence-dependent setup t...

in this paper, we study the problem of integrated capacitated hub location problem and seat inventory control considering concept and techniques of revenue management. we consider an airline company maximizes its revenue by utilizing the best network topology and providing proper booking limits for all itineraries and fare classes. the transportation system arises in the form of a star/star net...

In the petroleum supply chain, oil refined products are often delivered to distribution centers by pipelines since they provide the most reliable and economical mode of transportation over large distances. This paper addresses the optimal scheduling of a complex pipeline network with multiple branching lines. The main challenge is to find the optimal sequence and time of product injections/deli...

We consider the following problem. A set of non-preemptable jobs has to be scheduled on two identical parallel machines such that the makespan is minimized. Before processing, each job must be loaded on a machine, which takes a given setup time. All these setups have to be done by a single server which can handle at most one job at a time. For this problem, we propose three mixed integer linear...

Considering a set of points in a multi-dimensional space with an associated real value for each point, we want to find the box with the maximum sum of the values of the included points. This problem has applications in data mining and can be formulated as a mixed-integer linear program. We propose a branch-and-bound algorithm where the bounding is obtained by combinatorial arguments instead of ...

We present a Branch and Cut algorithm of the software package LaGO to solve nonconvex mixed-integer nonlinear programs (MINLPs). A linear outer approximation is constructed from a convex relaxation of the problem. Since we do not require an algebraic representation of the problem, reformulation techniques for the construction of the convex relaxation cannot be applied, and we are restricted to ...

A relevant amount of work has been devoted very recently to modeling and (heuristically) solving the NP-hard separation problem of famous classes of valid inequalities for mixed integer linear programs (MIPs). This task has been accomplished by using, in turn, mixed-integer linear models for the separation problem, and a general-purpose solver to actually find violated cuts—the so-called MIPpin...

In this paper recently developed mixed-integer programming (MIP) tools to the problem of optimal siting and sizing of distributed generators in a distribution network. Here three methodologies for solving the DGPP via mixed-integer linear programming (MILP) and mixed-integer nonlinear programming (MINLP) approaches are compared. The single MILP approach uses the well-known DC linear approximati...