Given n potential oil locations, where each has oil at a certain depth, we seek good trade-offs between the number of oil sources found and the total amount of drilling performed. The cost of exploring a location is proportional to the depth to which it is drilled. The algorithm has no clue about the depths of the oil sources at the different locations or even if there are any. Abstraction of t...

faults in computer networks may result in millions of dollars in cost. faults in a network need to be localized and repaired to keep the health of the network. fault management systems are used to keep today’s complex networks running without significant cost, either by using active techniques or passive techniques. in this paper, we propose a novel approach based on imperialist competitive alg...

Algorithms for the group testing problem when there is no a priori information on the number of defective items are considered. The efficiency criterion used is the competitive ratio, which is the ratio of the number of tests required by an algorithm when there is no a priori information on the number of defective items, to the number of tests required by an optimal algorithm when the number of...

We study an online model for the maximum k-vertex-coverage problem, where given a graph G = (V,E) and an integer k, we ask for a subset A ⊆ V , such that |A| = k and the number of edges covered by A is maximized. In our model, at each step i, a new vertex vi is revealed, and we have to decide whether we will keep it or discard it. At any time of the process, only k vertices can be kept in memor...

We consider online competitive algorithms for the problem of collecting weighted items froma dynamic set S, when items are added to or deleted from S over time. The objective isto maximize the total weight of collected items. We study the general version, as well asvariants with various restrictions, including the following: the uniform case, when all itemshave the same weight, ...

This paper gives a randomized competitive distributed paging algorithm called Heat & Dump. The competitive ratio is logarithmic in the total storage capacity of the network, this is optimal to within a constant factor. This is in contrast to the linear optimal deterministic competitive ratio BFR].

We study the online specialization problem, where items arrive in an online fashion for processing by one of n different methods. Each method has two costs: a processing cost (paid once for each item processed), and a set-up cost (paid only once, on the method’s first use). There are n possible types of items; an item’s type determines the set of methods available to process it. Each method has...

Article history: Received 18 January 2011 Received in revised form 14 March 2012 Accepted 3 August 2012 Available online xxxx

a new powerful optimization algorithm inspired from colonizing weeds is utilized to solve the well-known quadratic assignment problem (qap) which is of application in a large number of practical areas such as plant layout, machinery layout and so on. a set of reference numerical problems from qaplib is taken in order to evaluate the efficiency of the algorithm compared with the previous ones wh...