Titlebook: Integer Programming and Combinatorial Optimization; 20th International C Andrea Lodi,Viswanath Nagarajan Conference proceedings 2019 Spring

Anthropoid

Fixed-Order Scheduling on Parallel Machines,of . identical machines in order to minimize the sum of weighted completion times. The twist is that for machine the jobs assigned to it must obey the order of the input sequence, as is the case in multi-server queuing systems. We establish a constant factor approximation algorithm for this (strongl

coagulate

Online Submodular Maximization: Beating 1/2 Made Simple,perspectives. In particular, it has been studied in a natural online setting in which items arrive one-by-one and should be allocated irrevocably upon arrival. In this setting, it is well known that the greedy algorithm achieves a competitive ratio of ., and recently Kapralov . [.] showed that this

Sinus-Rhythm

Improving the Integrality Gap for Multiway Cut,partition the node set of the graph into . non-empty parts each containing exactly one terminal so that the total weight of the edges crossing the partition is minimized. The multiway cut problem for . is APX-hard. For arbitrary ., the best-known approximation factor is 1.2965 due to Sharma and Vond

落叶剂

-sparsity Approximation Bounds for Packing Integer Programs, . which is at least 1. Previous work by Bansal et al. [.] obtained an .-approximation ratio where . is the maximum number of nonzeroes in any column of . (in other words the .-column sparsity of .). They raised the question of obtaining approximation ratios based on the .-column sparsity of . (deno

Obsessed

A General Framework for Handling Commitment in Online Throughput Maximization,mine a preemptive single-server schedule which maximizes the number of jobs that complete on time. To circumvent known impossibility results, we make a standard slackness assumption by which the feasible time window for scheduling a job is at least . times its processing time, for some .. We quantif

罗盘

ROOF

,On Friedmann’s Subexponential Lower Bound for Zadeh’s Pivot Rule, Zadeh’s pivot rule had long been a promising candidate, before Friedmann (IPCO, 2011) presented a subexponential instance, based on a close relation to policy iteration algorithms for Markov decision processes (MDPs). We investigate Friedmann’s lower bound construction and exhibit three flaws in hi

VEN

等待

Integer Programming and Incidence Treedepth,ucture of its constraint matrix on the other side. To that end, integer linear programming is fixed-parameter tractable with respect to the primal (or dual) treedepth of the Gaifman graph of its constraint matrix and the largest coefficient (in absolute value). Motivated by this, Koutecký, Levin, an

暴行

A Bundle Approach for SDPs with Exact Subgraph Constraints,al NP-hard graph optimization problems. Solving these relaxations is a computational challenge because of the potentially large number of violated subgraph constraints. We introduce a computational framework for these relaxations designed to cope with these difficulties. We suggest a partial Lagrang