N COMPUTER applications we are used to live with approximation. Var I ious notions of
approximation appear, in fact, in many circumstances. One notable example is the type of …

Graph colouring and its generalizations are useful tools in modelling a wide variety of
scheduling and assignment problems. In this paper we review several variants of graph …

Due to the fact that no NP-complete problem can be solved in polynomial time (unless P=
NP), many approximability results (both positive and negative) of NP-hard optimization …

Graph coloring is one of the oldest and best-known problems of graph theory. Statistics
show that graph coloring is one of the central issues in the collection of several hundred …

The minimum sum coloring problem (MSCP) is a variant of the well-known vertex coloring
problem which has a number of AI related applications. Due to its theoretical and practical …

At the core of the seminal graph minor theory of Robertson and Seymour is a powerful
structural theorem capturing the structure of graphs excluding a fixed minor. This result is …

The success of a P2P file-sharing network highly depends on the scalability and versatility of
its search mechanism. Two particularly desirable search features are scope (ability to find …

The input to the min sum set cover problem is a collection of n sets that jointly cover m
elements. The output is a linear order on the sets, namely, in every time step from 1 to n …

Cloud platforms enable enterprises to lease computing power in the form of virtual
machines. An important problem for such enterprise users is to understand how many and …

Modern planetary-scale online services have massive data to transfer over the wide area
network (WAN). Due to the tremendous cost of building WANs and the stringent timing …