We study a vacation-type queueing model, and a singleserver multi-queue polling model, with the special feature of retrials. Just before the server arrives at a station there is some deterministic glue period. Customers (both new arrivals and retrials) arriving at the station during this glue period will be served during the visit of the server. Customers arriving in any other period leave imme...

A bstract . Graph transformations tha.t ma.y be reduced to the form x(l +l) = x(I)+vu(Ax(I)), with x(I),x(I+1 ) E R , u convex function and A symmet ric mat rix, are studied. In par t icular , a reduction to t he class is exhibited for some graph t ransformations recentl y introduced by Odlyzko and Randall. Fur ther result s on periods, quasi-periods, and pre-periods are presented. A class of m...

We study a vacation-type queueing model, and a singleserver multi-queue polling model, with the special feature of retrials. Just before the server arrives at a station there is some deterministic glue period. Customers (both new arrivals and retrials) arriving at the station during this glue period will be served during the visit of the server. Customers arriving in any other period leave imme...

Methods: This is a multi-center retrospective study. Newly diagnosed IBD cases from January 1995 to December 2009 (n = 427) in Eastern China were included. Study protocol was approved by Institutional Review Board. Disease severity was assessed by Montreal classification. It was divided into two periods: 1995-2004 and 2005-2009. The epidemiological and clinical characteristics of ulcerative col...

A new sea ice algorithm, Environment Canada’s Ice Concentration Extractor (ECICE), combines several different satellite sensors to extract ice types and concentrations. Results are presented for the Arctic region during the ice growth season of 2007/08. Three ice types are specified: young, first year and multi year. The algorithm was applied using AMSR-E (36.5 GHz channel) combined with backsc...

Supply chain management (SCM) is a subject that has found so much attention among different commercial and industrial organizations due to competing environment of products. Therefore, integration of constituent element of this chain is a great deal. This paper proposes a multi objective production-allocation and distribution planning problem (PADPP) in a multi echelon supply chain network. We ...