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31.
Bounded degree networks like deBruijn graphs or wrapped butterfly networks are very important from VLSI implementation point of view as well as for applications where the computing nodes in the interconnection networks can have only a fixed number of I/O ports. One basic drawback of these networks is that they cannot provide a desired level of fault tolerance because of the bounded degree of the nodes. On the other hand, networks like hypercube (where degree of a node grows with the size of a network) can provide the desired fault tolerance but the design of a node becomes problematic for large networks. In their attempt to combine the best of the both worlds, authors in [IEEE Transactions on Parallel and Distributed Systems 4(9) (1993) 962] proposed hyper-deBruijn (HD) networks that have many additional features of logarithmic diameter, partitionability, embedding, etc. But, HD networks are not regular, are not optimally fault tolerant and the optimal routing is relatively complex. Our purpose in the present paper is to extend the concepts used in the above-mentioned reference to propose a new family of scalable network graphs that retain all the good features of HD networks and at the same time are regular and maximally fault tolerant; the optimal point to point routing algorithm is significantly simpler than that of the HD networks. We have developed some new interesting results on wrapped butterfly networks in the process. 相似文献
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33.
An inertia-adaptive particle swarm system with particle mobility factor for improved global optimization 总被引:2,自引:2,他引:0
Sayan Ghosh Swagatam Das Debarati Kundu Kaushik Suresh B. K. Panigrahi Zhihua Cui 《Neural computing & applications》2012,21(2):237-250
Particle Swarm Optimization (PSO) has recently emerged as a nature-inspired algorithm for real parameter optimization. This
article describes a method for improving the final accuracy and the convergence speed of PSO by firstly adding a new coefficient
(called mobility factor) to the position updating equation and secondly modulating the inertia weight according to the distance
between a particle and the globally best position found so far. The two-fold modification tries to balance between the explorative
and exploitative tendencies of the swarm with an objective of achieving better search performance. We also mathematically
analyze the effect of the modifications on the dynamics of the PSO algorithm. The new algorithm has been shown to be statistically
significantly better than the basic PSO and four of its state-of-the-art variants on a twelve-function test-suite in terms
of speed, accuracy, and robustness. 相似文献
34.
David B. Stringer Pradip N. Sheth Paul E. Allaire 《Journal of Intelligent Manufacturing》2012,23(2):155-162
This paper presents physics-based models as a key component of prognostic and diagnostic algorithms of health monitoring systems.
While traditionally overlooked in condition-based maintenance strategies, these models potentially offer a robust alternative
to experimental or other stochastic modeling data. Such a strategy is particularly useful in aerospace applications, presented
in this paper in the context of a helicopter transmission model. A lumped parameter, finite element model of a widely used
helicopter transmission is presented as well as methods of fault seeding and detection. Fault detection through diagnostic
vibration parameters is illustrated through the simulation of a degraded rolling-element bearing supporting the transmission’s
input shaft. Detection in the time domain and frequency domain is discussed. The simulation shows such modeling techniques
to be useful tools in health monitoring analysis, particularly as sources of information for algorithms to compare with real-time
or near real-time sensor data. 相似文献
35.
We propose a family of regular Cayley network graphs of degree three based on permutation groups for design of massively parallel systems. These graphs are shown to be based on the shuffle exchange operations, to have logarithmic diameter in the number of vertices, and to be maximally fault tolerant. We investigate different algebraic properties of these networks (including fault tolerance) and propose a simple routing algorithm. These graphs are shown to be able to efficiently simulate or embed other permutation group based graphs; thus they seem to be very attractive for VLSI implementation and for applications requiring bounded number of I/O ports as well as to run existing applications for other permutation group based network architectures. 相似文献
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Jnyana Ranjan Pati Subhajit Dutta Philippe Eliaers Pinakeswar Mahanta Pradip Kumar Chatterjee 《Drying Technology》2016,34(9):1073-1084
The intensification of interfacial mass, heat, and momentum transfer makes vortex chambers potentially interesting for the efficient drying of paddy, allowing shorter drying times and/or more compact equipment. The presence of a shell introduces particular challenges. Intraparticle diffusion limitations are strong and may reduce the advantage from intensified interfacial mass and heat transfer and the efficiency of air usage. Furthermore, high shear and normal stresses in the fast rotating particle bed may cause damage to the paddy shell, posing problems for transport and storage. With these specific aspects in mind, the use of vortex chambers for paddy drying is experimentally evaluated. 相似文献
39.
3D integration of ICs is an emerging technology where multiple silicon dies are stacked vertically. The manufacturing itself
is based on wafer-to-wafer bonding, die-to-wafer bonding or die-to-die bonding. Wafer-to-wafer bonding has the lowest yield
as a good die may be stacked against a bad die, resulting in a wasted good die. Thus the latter two options are preferred
to keep yield high and manufacturing costs low. However, these methods require dies to be tested separately before they are
stacked. A problem with testing dies separately is that the clock network of a prebond die may be incomplete before stacking.
In this paper we present a solution to address this problem. The solution is based on on-die Delay Lock Loop (DLL) implementations
that are only activated during testing prebond unstacked dies to synchronize disconnected clock regions. A problem with using
DLLs in testing is that they cannot be turned on or off within a single cycle. Since scan-based testing requires that test
patterns be scanned in at a slow clock frequency before fast capture clocks are applied, On-Product Clock Generation (OPCG)
must be used. The proposed solution addresses the above problems and allows a prebond with an incomplete clock network to
be tested with low skew. 相似文献
40.
Channel estimation in a multipath mobile communication system is addressed in this paper, and a novel approach based on the
linear prediction in frequency domain and the singular value decomposition technique is presented for joint estimation of
the angles of arrival and the time delays of multiple reflections of a known signal. Simulation results illustrating the performance
of the proposed algorithm are included, and the results show that the proposed method is close in accuracy when compared to
the iterative maximum-likelihood method. However, when the two methods are compared in computational complexity, it is demonstrated
that the proposed method reduces the complexity to nearly half of that of the maximum-likelihood method. The Cramer–Rao bounds
are computed for comparison. 相似文献