In many practical distribution networks, managers face significant uncertainties in demand, local price of building facilities, transportation cost, and macro and microeconomic parameters. This paper addresses design of distribution networks in a supply chain system which optimizes the performance of distribution networks subject to required service level. This service level, which is consider...

We present a single server in which customers arrive in batches and the server provides service one by one. The server provides two heterogeneous service stages such that service time of both stages is different and mandatory to all arriving customers in such a way that, after the completion of first stage, the second stage should also be provided to the customers. The server may subject to ran...

Savors is a visualization framework that supports the ingestion of data streams created by arbitrary command pipelines. Multiple data streams can be shown synchronized by time in the same or different views, which can be arranged in any layout. These capabilities combined with a powerful parallelization mechanism and interaction models already familiar to administrators allows Savors to display...

In this paper we introduce a new model of on-line problems called metrical service systems. An instance of a metrical service system is speci ed by a metric space M and a set R of requests, where each r 2 R is a subset of M . There is one server that can move in M . At every time step a request r 2 R is speci ed, and the server must move to a point x 2 r to serve the request r. We also have the...

Many fundamental questions in evolution remain unresolved despite the abundance of genetic sequence data that is now available. This state of affairs is partly due to the lack of simultaneously efficient and accurate computational methods for inferring evolutionary trees. Efficient methods are critical since the abundance of sequence data has resulted in the need to analyze large datasets. Meth...

If standard-precision computations do not lead to the desired accuracy, then it is reasonable to increase precision until we reach this accuracy. What is the optimal way of increasing precision? One possibility is to choose a constant q > 1, so that if the precision which requires the time t did not lead to a success, we select the next precision that requires time q · t. It was shown that amon...