We investigate the max flow time scheduling problem in the off-line and on-line setting. We prove positive and negative theoretical results. In the off-line setting, we address the unrelated parallel machines model and present the first known fully polynomial time approximation scheme, when the number of machines is fixed. In the on-line setting and when the machines are identical, we analyze t...

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 firstly describe a technique named Duplicating, which duplicates machines in batch scheduling environment. Then we discuss several applications of Duplicating in solving batch scheduling problems, for the batch scheduling problem on unrelated parallel machines to minimize makespan, we give an (4− 2 B )-approximation algorithm and an (2− 1 B + ǫ) algorithm when m is fixed. We a...

In this paper, the flow-shop scheduling problem with unrelated parallel machines at each stage as well as sequence-dependent setup times under minimization of the sum of earliness and tardiness are studied. The processing times, setup times and due-dates are known in advance. To solve the problem, we introduce a hybrid memetic algorithm as well as a particle swarm optimization algorithm combine...

This paper presents a bi-objective MIP model for the flexible flow shop scheduling  problem (FFSP) in which the total weighted tardiness and the energy consumption are minimized simultaneously. In addition to considering unrelated machines at each stage, the set-up times are supposed to be sequence- and machine-dependent, and it is assumed that jobs have different release tim...

This paper considers the economic lot and delivery scheduling problem in a two-echelon supply chains, where a single supplier produces multiple components on a flexible flow line (FFL) and delivers them directly to an assembly facility (AF). The objective is to determine a cyclic schedule that minimizes the sum of transportation, setup and inventory holding costs per unit time without shortage....

We study the problem of truthfully scheduling m tasks to n selfish unrelated machines, under objective makespan minimization, as was introduced in seminal work Nisan and Ronen (in: The 31st Annual ACM symposium on Theory Computing (STOC), 1999). Closing current gap [2.618, n] approximation ratio deterministic truthful mechanisms is a notorious open field algorithmic mechanism design. provide fi...

A new hybrid flow shop scheduling problem with blocking is studied. The problem is characterized by multistage unrelated parallel machines and no intermediate buffer. Firstly, the math model of the hybrid scheduling problem is constructed. And then the computation method of production period is given. Due to there is no intermediate buffer, and there are unrelated parallel machines in multi-sta...