When a set of permutations comprising a pattern class C is submitted as input to a priority queue the resulting output is again a pattern class C′. The basis of C′ is determined for pattern classes C whose basis elements have length 3, and is finite in these cases. An example is given of a class C with basis {2431} for which C′ is not finitely based. Mathematics Subject Classification: 05A05, 6...

Shanthikumar [10] studied the priority M/G/1 queue with server vacations and found that the difference between the waiting time distribution under the non-preemptive priority and that under the preemptive-resume priority is independent of the vacation policy. We extend this interesting property i) to the generalized vacations which includes the two vacation policies considered by Shanthikumar, ...

Priority trees are a certain data structure used for priority queue administration. Under the model that all permutations of the numbers 1, . . . , n are equally likely to construct a priority tree of size n we study the following parameters in size-n trees: depth of a random node, number of right edges to a random node, and number of descendants of a random node. For all parameters studied we ...

We study the impact of using different priority queues in the performance of Dijkstra’s SSSP algorithm. We consider only general priority queues that can handle any type of keys (integer, floating point, etc.); the only exception is that we use as a benchmark the DIMACS Challenge SSSP code [1] which can handle only integer values for distances. Our experiments were focussed on the following: 1....

We present a new algorithm for concurrent access to array-based priority queue heaps. Deletions proceed top-down as they do in a previous algorithm due to Rao and Kumar 6], but insertions proceed bottom-up, and consecutive insertions use a bit-reversal technique to scatter accesses across the fringe of the tree, to reduce contention. Because insertions do not have to traverse the entire height ...

The objective ofthis paper is to study a communication system based on a M(X)/D/1 queueing system representing a cell-switch network like Asynchronous Transfer Mode (ATM) network. Network structure consists of a single link modeled as a batch arrival markovian queue with non-preemptive head of the line priority service. Network manager (NM) is assumed to be a decision maker at a Management Info...

investigation of desertification trend requires an understanding of phenomena that create changes singly or action and reaction together in an area that these changes were led to the desertification and land degradation. in the investigation of pedological criterion affecting on land degradation in alluvial fans, first, the map of units was created by overlaying and crossing maps of slope class...

pedological criterion affecting desertification in alluvial fans was investigated, for which the map of units was prepared by crossing maps of land use, geology, slope classes and grid layer created by the extension of et geo-wizards in arcgis 10.3. three indices of salinity, erodibility, and permeability of soil were considered and classified. weights of criteria and consistency ratio were cal...

Purpose From the late 1980s and onwards health care in Sweden has come under increasing financial pressure, forcing policy makers to consider restrictions. The purpose of this paper is to review experiences and to establish lessons of formal priority setting in four Swedish regional health authorities during the period 2003-2012. Design/methodology/approach This paper draws on a variety of sour...

Datacenters consolidate diverse applications to improve utilization. However when multiple applications are colocated on such platforms, contention for shared resources like networks-on-chip (NoCs) can degrade the performance of latency-critical online services (high-priority applications). Recently proposed bufferless NoCs (Nychis et al.) have the advantages of requiring less area and power, b...