The coupled task problem is to schedule n jobs on one machine where each job consists of two subtasks with required delay time between them. The objective is to minimize the makespan. This problem was analyzed in depth by Orman and Potts [3]. They investigated the complexity of different cases...

In this note, we prove ??-completeness of the following problem: Given a set of trams of different types, which are stacked on sidings in their depot and an order in which trams of specified types are supposed to leave. Is there an assignment of trams to departure times without any shunting...

For more than two machines, and when preemption is forbidden, the computation of minimum makespan schedules for the open-shop problem is NP-hard. Compared to the flow-shop and the job-shop, the open-shop has free job routes which lead to a much larger solution space, to smaller gaps between the...

Ideal schedules reach both minimum maximum completion time and minimum total completion time of jobs. It is known that there exist computable in polynomial time ideal nonpreemptive two-machine schedules of unit-time operation jobs with equal release dates and arbitrary precedence constraints on...

In this paper we study the single-machine problem 1|chains(l), p <Subscript> j </Subscript>=p|∑ C <Subscript> j </Subscript> in which jobs with constant processing times and generalized precedence constraints in form of chains with constant delays are given. One has to schedule the jobs on a single machine such that all delays between...</subscript></subscript>

Brucker et al. (Math Methods Oper Res 56: 407–412, 2003) have given an O(n <Superscript>2</Superscript>)-time algorithm for the problems <InlineEquation ID="IEq1"> <EquationSource Format="TEX">$$P \mid p_{j}=1, r_{j}$$</EquationSource> </InlineEquation>, outtree <InlineEquation ID="IEq2"> <EquationSource Format="TEX">$$\mid \sum C_{j}$$</EquationSource> </InlineEquation> and <InlineEquation ID="IEq3"> <EquationSource Format="TEX">$$P \mid pmtn, p_{j}=1, r_{j}$$</EquationSource> </InlineEquation>, outtree <InlineEquation ID="IEq4"> <EquationSource Format="TEX">$$\mid \sum C_{j}$$</EquationSource> </InlineEquation>. In this note, we show that their algorithm admits an...</equationsource></inlineequation></equationsource></inlineequation></equationsource></inlineequation></equationsource></inlineequation></superscript>

Multilevel processor-sharing (MLPS) disciplines were originally introduced by Kleinrock (in computer applications 1976) but they were forgotten for years. However, due to an application related to the service differentiation between short and long TCP flows in the Internet, they have recently...