We show that certain twisting deformations of a family of supersolvable groups are simple as Hopf algebras. These groups are direct products of two generalized dihedral groups. Examples of this construction arise in dimensions 60 and pq, for prime numbers p, q with q|p − 1. We also show that certain twisting deformation of the symmetric group is simple as a Hopf algebra. On the other hand, we p...

The Congestion in wireless sensor networks occurs when packets arrive at a fully loaded buffer of a sensor node. Due to lack of space in the buffer, packets are dropped. It also leads to packet delay, retransmission of packets, reduced QoS and throughput. A hybrid of rate control and resource control algorithms can be used to control congestion considering the priority of the packets. Congestio...

We consider a stochastic fluid flow model with a single server andK infinite capacity buffers. The input to the k-th buffer is a Markovian on-off process that transmits fluid at a constant rate pk while it is on and at rate 0 while it is off. The fluid is emptied from the buffers by a single server at a constant rate μ according to a static priority service discipline in which class 1 fluid has...

We consider a stochastic fluid flow model with a single server and K infinite capacity buffers. The input to the k-th buffer is a Markovian on-off process that transmits fluid at a constant rate pk while it is on and at rate 0 while it is off. The fluid is emptied from the buffers by a single server at a constant rate μ according to a static priority service discipline in which class 1 fluid ha...

In this paper we study a queueing model with a server that changes its service rate according to a nite birth and death process. The object of interest is the simultaneous distribution of the number of customers in the system and the state of the server in steady-state. The model can be applied to the performance analysis of (low priority) Available Bit Rate (ABR) traac at an ATM switch in the ...

We consider a stochastic fluid flow model with a single server and K infinite capacity buffers. The input to the k-th buffer is a Markovian on-off process that transmits fluid at a constant rate pk while it is on and at rate 0 while it is off. The fluid is emptied from the buffers by a single server at a constant rate μ according to a static priority service discipline in which class 1 fluid ha...

Priority queues and double-ended priority queues are fundamental data types in Computer Science, and various data structures have been proposed to implement them. In particular, diamond deques, interval heaps, min-max-pair heaps, and twin-heaps provide implicit structures for double-ended priority queues. Although these heap-like structures are essentially the same when they are presented in an...

In this paper we study a queueing model with a server that changes its service rate according to a nite birth and death process. The object of interest is the simultaneous distribution of the number of customers in the system and the state of the server in steady-state. The model can be applied to the performance analysis of (low priority) Available Bit Rate (ABR) tra c at an ATM switch in the ...

In this paper we show that the widely used normalization constraint ∑ n i=1 wi = 1 does not apply to the priority vectors associated with reciprocal relations, whenever additive transitivity is involved. We show that misleading applications of this type of normalization may lead to unsatisfactory results and we give some examples from the literature. Then, we propose an alternative normalizatio...

In this paper we show how to implement bounded ordered dictionaries, also called bounded priority queues, in O(log log N) time per operation and O(n) space. Here n denotes the number of elements stored in the dictionary and N denotes the size of the universe. Previously, this time bound required O(N) space E77].