623251
Isomorphism classes of bipartite cycle permutation graphs
16002222
Isomorphism classes of cycle permutation graphs
Abstract In this paper, we construct a cycle permutation graph as a covering graph over the dumbbell graph, and give a new characterization of when two given cycle permutation graphs are isomorphic by a positive or a negative natural isomorphism. Also, we count the isomorphism classes of cycle permutation graphs up to positive natural isomorphism, and find the number of distinct cycle permutation graphs isomorphic to a given cycle permutation graph by a positive/negative natural isomorphism. As a consequence, we obtain a formula for finding the number of double cosets of the dihedral group in the symmetric group.
40285902
Isoperimetric numbers and bisection widths of double coverings of a complete graph
1336097
Distributed synchronous control units for dataflow graphs under allocation of telescopic arithmetic units
In order to enjoy the performance improvement effects of variable computation time arithmetic units at a system level, we propose a new synchronous control unit design methodology for dataflow graphs under allocation of a telescopic arithmetic unit, which is one of the well-known synchronous variable computation time arithmetic units. The proposed method generates an independent synchronous controller for each component arithmetic unit, and builds a distributed synchronous control unit through integrating the derived controllers. The distributed structure of the final synchronous control unit maximizes the performance improvement effect of telescopic arithmetic units through a complete preservation of original concurrency among operations.
29667666
Building a distributed asynchronous control unit through automatic derivation of hierarchically decomposed AFSMs from a CDFG
Although there are several successful asynchronous logic synthesis tools, it is still unwieldy for designers to conceive and describe behaviors for a number of controllers constituting an asynchronous control unit of a target system manually. In this paper, building a distributed asynchronous control unit automatically through automatic derivation of hierarchically decomposed AFSMs from a CDFG is suggested. A resulting control unit consists of small asynchronous controllers and has complete separation of 'execution controllers' and 'execution order controllers'. This distributive feature leads to significant improvements in the aspects of area, performance and synthesis time of derived control circuits.
29011378
The achromatic number of the union of cycles
The achromatic number of a graph G is the largest number of colors which can be assigned to the vertices of G so that adjacent vertices get different colors and each pair of distinct colors appears on the ends of some edge. We show that the achromatic number of the disjoint union of k cycles of length l1, l2 ...., lk is equal to the achromatic number of the cycle of length p = Σi=1k li for any k ≤ √p/2, and that the achromatic number of the disjoint union of k triangles (resp. quadrangles) is equal to the achromatic number of the cycle of length 3k (resp. 4k) for any positive integer k.
46430091
Design of VDSL Networks for the High Speed Internet Services
VDSL is recently getting more attention as the efficient xDSL technology. VDSL can be used for next generation Grid computing. Because VDSL is last mile network, they designed multimedia supplying VDSL networks through combining it with core network or access network properly. Core network was designed with IP network and ATM network and simulated through COMNET. In the measure result (Bit rate, Delay) of the simulation, we knew that IP network is superior to ATM network in terms of measure result.
7032611
Utility-Optimal Medium Access Control: Reverse and Forward Engineering
This paper analyzes and designs medium access control (MAC) protocols for wireless ad-hoc networks through the network utility maximization (NUM) framework. We first reverse-engineer the current exponential backoff (EB) type of MAC protocols such as the BEB (binary exponential backoff) in the IEEE 802.11 standard through a non-cooperative game- theoretic model. This MAC protocol is shown to be implicitly maximizing, using a stochastic subgradient, a selfish local utility at each link in the form of expected net reward for successful transmission. While the existence of a Nash equilibrium can be established, neither convergence nor social welfare optimality is guaranteed due to the inadequate feedback mechanism in the EB protocol. This motivates the forward-engineering part of the paper, where a network-wide utility maximization problem is for- mulated, using a collision and persistence probability model and aligning selfish utility with total social welfare. By adjusting the parameters in the utility objective functions of the NUM problem, we can also control the tradeoff between efficiency and fairness of radio resource allocation through a rigorous and systematic design. We develop two distributed algorithms to solve the MAC design NUM problem, which lead to random access protocols that have slightly more message passing overhead than the current EB protocol, but significant potential for efficiency and fairness improvement. We provide readily-verifiable sufficient conditions under which convergence of the proposed algorithms to a global optimality of network utility can be guaranteed, and through numerical examples illustrate the value of the NUM approach to the complexity-performance tradeoff in MAC design.