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...

The major factors of insecurity in the East, away from the security of geopolitical area were because of the formation of political management in the nineteenth century colonial style. The security factor in the vast region of the East that encompasses at least three countries of Iran and Afghanistan and Pakistan is very important and highly effective. It reached its peak colonial Anglo-Russian...

In engineering, flood routing is an important technique necessary for the solution of a floodcontrol problem and for the satisfactory operation of a flood-prediction service. A simple conceptual model like the Muskingum model is very effective for the flood routing process. One challenge in application of the Muskingum model is that its parameters cannot be measured physically. In this article ...

In today's design, system complexity and increasing demand for safer, more efficient and less costly systems have created new challenges in science and engineering. Locomotives are products which are designed according to market order and technical needs of customers. Accordingly, targets of companies, especially designers and manufacturers of locomotives, have always been on the path of progre...

We study an online model of fair division designed to capture features of a real world charity problem. We consider two simple mechanisms for this model in which agents simply declare what items they like. We analyse axiomatic properties of these mechanisms such as strategy-proofness and envy freeness. Finally, we perform a competitive analysis and compute the price of anarchy.

In this paper we investigate parallel searching on m concurrent rays. We assume that a target t is located somewhere on one of the rays and that a group of m point robots has to reach t. Furthermore, we assume that the robots have no way of communicating over distance. Given a strategy S we are interested in the competitive ratio which is deened as the ratio of the time needed by the robots usi...