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11.
The 3DP (3-Dimensional Processor), a parallel-computing architecture that targets problems that have a 3-D numerical structure and require numerous calculations on 3-D vectors, is described. The 3DP architecture differs from traditional scalar architectures in that it operates directly on vectors. It differs from general parallel architectures in that it can solve problems that predict the behavior of highly coupled systems, and it differs from vector architectures in that it runs efficiently on length-3 vectors. Object-oriented programming on the 3DP and programming the 3DP in C++ are discussed. 3DP performance is reviewed, and the current implementation of the 3DP architecture, as an attached processor that plugs directly into Sun host VMEbus, is described 相似文献
12.
P. Bala Srinivasan C. V. Krishnakumar N. Krishnaraj 《Journal of Materials Engineering and Performance》2002,11(5):509-515
Salt bath nitrocarburizing is a well-known thermochemical diffusion process for enhancing the tribological and corrosion properties
of ferrous components. The current work describes the role of a compound layer developed during nitrocarburizing, both in
the ferritic and austenitic regimes of Fe-N-C system, on the sliding wear behavior of a medium carbon steel. The wear behavior
of the nitrocarburized steel discs was assessed by the pin-on-disc tests (ASTM G 99-99) under different normal loads running
against a hardened SAE52100 pin. It was observed that the compound layer on the surface not only controlled the wear rate
but also resisted the adhesive wear/transfer of material from pin to disc, aside from providing low-friction coefficients. 相似文献
13.
14.
Thomachan.A. Kattakayam Sumanta Khan Kandadai Srinivasan 《Solar Energy Materials & Solar Cells》1996,44(1):25
This article describes the development of an instrumentation system for characterizing photovoltaic panels. It uses an add on card (which contains DAC, ADC and digital input/output ports) in conjunction with a PC-AT. The panels in a field are selected in succession through a set of relays actuated by the digital output port. The selected panel is loaded in discreet steps by a transistor loading circuit which is activated by the digital to analog convertor to trace the most significant portion of the I-V curve. The data shows that the power output is invariably lower than that specified by the manufacturer. The reasons for drop in output have been analyzed. It is shown that these effects can be represented by the curvature of I-V characteristic at the maximum power point (OP). The loss of power due to accumulation of dust and the increase in temperature of the panels can be significant. 相似文献
15.
Local stress and strain variations in the deformation zone can be ascertained by measuring hardness. Hardness is correlated
with strain and stress. The expressions discussed later are useful in determining the local variations in stress and strain
from hardness measurement. It is a simple method compared to visioplasticity. One can estimate the forces required for a forming
process. It helps in the choice of equipment, design of tooling and selection of lubricant for the particular process. 相似文献
16.
Ti–TiN and TiN–CrN nanomultilayers were thermally stable retaining uniform and sharp layer interfaces up to 24 h at 773 K, without any oxidation or phase transformation accompanying each individual layer. Decreasing the multilayer spacing resulted in an increase in the hardness in both cases. The coating hardness was found to be independent of the substrate type, when applied on HS718, Ti64 and HCHCr substrates. In scratch testing, the multilayers displayed a better resistance to the onset of failure, as compared to the monolayer TiN. The substrate plasticity played an important role in determining the coating failure mode. Self-mated wear tests revealed the CrN–TiN system to exhibit the best wear behaviour, both at room temperature and at 773 K. The Ti–TiN coatings are more accommodative with all three substrates, as compared to TiN–CrN and TiN. 相似文献
17.
We formulate and analyze a model of voice and data burst traffic for cellular digital packet data (CDPD). To develop a tractible model, we make some reasonable simplifying assumptions to model the voice traffic and one of the logical CDPD channels as an M/M/1 queue in a random environment. Rather than explicitly solve the resulting matrix quadratic equation, we develop an asymptotic analysis that gives us simple approximate formulas (with error bounds) for many performance measures of interest. In particular, one metric that we highlight comes from using our approximate mean data burst delay formula to characterize the performance of a set of interacting logical CDPD channels. We do so by describing it in terms of an equivalent number of independent, dedicated CDPD channels, We can use this metric to suggest what the optimal number of logical CDPD channels for a given system should be 相似文献
18.
Auciello O. Pacheco S. Sumant A.V. Gudeman C. Sampath S. Datta A. Carpick R.W. Adiga V.P. Zurcher P. Zhenqiang Ma Hao-Chih Yuan Carlisle J.A. Kabius B. Hiller J. Srinivasan S. 《Microwave Magazine, IEEE》2007,8(6):61-75
Next-generation military and civilian communication systems will require technologies capable of handling data/ audio, and video simultaneously while supporting multiple RF systems operating in several different frequency bands from the MHz to the GHz range [1]. RF microelectromechani-cal/nanoelectromechanical (MEMS/NEMS) devices, such as resonators and switches, are attractive to industry as they offer a means by which performance can be greatly improved for wireless applications while at the same time potentially reducing overall size and weight as well as manufacturing costs. 相似文献
19.
The wide electrochemical window and ion exchange properties of a room-temperature ionic liquid (RTIL) have been exploited for the extraction of palladium from nitric acid medium into ionic liquid phase — followed by direct electrodeposition of the metal from the organic phase. Extraction of palladium by commercial Aliquat 336 ionic liquids, tri-n-octylmethylammonium chloride (TOMAC) and tri-n-octylmethylammonium nitrate (TOMAN), was studied as a function of [HNO3], [NO3−] and [TOMAN]. The distribution ratio (DPd(II)) of palladium in TOMAN increased with an increase in the concentration of nitric acid and passed through a maximum at 1.0 M nitric acid. In contrast, the DPd(II) value of palladium in TOMAC decreased continuously with an increase in the concentration of nitric acid. Substantial amounts of water and nitric acid were also co-extracted into the organic phase with palladium. 相似文献
20.
Towards an effective integration of cellular users to the structured Peer-to-Peer network 总被引:1,自引:1,他引:0
Mohammad Zulhasnine Changcheng Huang Anand Srinivasan 《Peer-to-Peer Networking and Applications》2012,5(2):178-192
Integration of cellular users into the peer-to-peer (P2P) network is still in limbo due to limitations caused by heterogeneity,
mobility and time-varying capacities of the wireless channel. If traditional Chord is employed to include users from the cellular
networks, users under the same base station scatter in logical topology randomly. In this paper, we present a novel cellular
Chord (C-Chord) P2P system that integrates the cellular users into the well-established structured P2P network in a topology-aware
fashion. C-Chord offers the cellular users a choice of downloading contents either from the Internet peers at a faster rate
or from other cellular users from the same base station avoiding the Internet data penalty. We also incorporate the peer selection
module based on stable marriage problem that chooses the appropriate candidate from the discovered potential senders. We conduct
extensive simulations to evaluate the performance of the proposed C-Chord P2P system and the peer selection module. Simulation
results show that the path-length per lookup query is smaller than that of the traditional Chord system. Overhead due to renewal
of routing information is also smaller for the cellular users in the C-Chord system. We also measure the throughput at the
cellular receivers to analyze the effects of selecting peers either from same base station or from outside the Internet gateway.
Throughput also increases dramatically due to an intelligent selection of peers among the potential senders. 相似文献