József Békési

New lower bounds for certain classes of bin packing algorithms

On-line algorithms have been extensively studied for the one-dimensional bin packing problem. In this paper, we investigate two classes of one-dimensional bin packing algorithms, and we give better lower bounds for their asymptotic worst-case behavior. For on-line algorithms so far the best lower bound was given by van Vliet in (1992) [12]. He proved that there is no on-line bin packing algorithm with better asymptotic performance ratio than 1.54014.... In this paper, we give an improvement on this bound to 248161=1.54037... and we investigate the parametric case as well. For those lists where the elements are preprocessed according to their sizes in non-increasing order, Csirik et al. (1983) [1] proved that no on-line algorithm can have an asymptotic performance ratio smaller than 87. We improve this result to 5447.

An exact algorithm for scheduling identical coupled tasks

Abstract.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 depending on the lengths ai and bi of the two subtasks and the delay time Li. -hardness proofs or polynomial algorithms were given for all cases except for the one where ai=a, bi=b and Li=L. In this paper we present an exact algorithm for this problem with time complexity O(nr2L) where holds. Therefore the algorithm is linear in the number of jobs for fixed L.

Lower Bound for the Online Bin Packing Problem with Restricted Repacking

In 1996 Ivkovic and Lloyd [A fundamental restriction on fully dynamic maintenance of bin packing, Inform. Process. Lett., 59 (1996), pp. 229-232] gave the lower bound

The optimal absolute ratio for online bin packing

\frac{4}{3}

Black and White Bin Packing

on the asymptotic worst-case ratio for so-called fully dynamic bin packing algorithms, where the number of repackable items in each step is restricted by a constant. In this paper we improve this result to about

Greedy Algorithms for On-Line Data Compression

1.3871

Online Results for Black and White Bin Packing

. We present our proof for a semionline case of the classical bin packing, but it works for fully dynamic bin packing as well. We prove the lower bound by analyzing and solving a specific optimization problem. The bound can be expressed exactly using the Lambert

Semi-on-line bin packing: a short overview and a new lower bound

W

Improved analysis of an algorithm for the coupled task problem with UET jobs

function.

An Integrated Framework for Bus Logistics Management: Case Studies

We present an online bin packing algorithm with absolute competitive ratio 5/3, which is optimal.