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141.
A novel optical burst switching (OBS) high speed network architecture has been proposed. To verify its feasibility and evaluate its performance, just-enough-time (JET) signaling has been considered as a high performance protocol. In the proposed architecture, to avoid burst losses, firstly, a short-prior- confirmation-packet (SPCP) is sent over the control channel that simulates the events that the actual packet will experience. Once SPCP detects a drop at any of the intermediate nodes, the actual packet is not sent but the process repeats. In order to increase network utilization, cost effectiveness and to overcome some limitations of conventional OBS, inherent codes (e.g., orthogonal optical codes (OOC)), which are codified only in intensity, has been used. Through simulations, it shows that a decrease in burst loss probability, cost effectiveness and a gain in processing time are obtained when optical label processing is used as compared with electronic processing. 相似文献
142.
Tripathi S Armstrong DS Christy ME Clark JH Gorringe TP Hasinoff MD Kovash MA Wright DH Zołnierczuk PA 《Physical review letters》2002,89(25):252501
We report the first observation of double radiative capture on pionic hydrogen. The experiment was conducted at the TRIUMF cyclotron using the RMC spectrometer and detected gamma-ray coincidences following pi(-) stops in liquid hydrogen. We found the branching ratio for double radiative capture to be [3.05+/-0.27(stat)+/-0.31(syst)]x10(-5). The measured branching ratio and angle-energy distributions support the theoretical prediction of a dominant contribution from the pipi-->gammagamma annihilation mechanism. 相似文献
143.
144.
Tripathi V Navin A Mahata K Ramachandran K Chatterjee A Kailas S 《Physical review letters》2002,88(17):172701
Results for the cross section and average angular momentum for complete fusion at energies around the Coulomb barrier are presented for 7Li with 165Ho. Comparison of the cross sections with a one-dimensional barrier penetration model, using a potential consistent with the measured elastic scattering, showed a reduction above the barrier and an enhancement below it. An increase in the measured average angular momentum, , above the barrier and its consistency with that obtained from the fusion excitation function for weakly bound nuclei, is reported. These results together with a reanalysis of existing data conclusively demonstrate that the effect of breakup on fusion is coherent, like coupling to any nonelastic channel. 相似文献
145.
In this paper the general non-static axially symmetric line element has been considered in the context of Petrov Classification.
The space-time is found to be of various Petrov Types under different circumstances. The necessary algebraic conditions for
such a space-time to be of class one have also been derived. It is found that there exists only one solution representing
a plane symmetric class-one null-electromagnetic field. 相似文献
146.
The energy transfer phenomenon has been studied from Tb3+ → Nd3+ and Tb3+ → Ho3+ in DMSO. A diffusion limited dipole-dipole mechanism of energy transfer is suggested for both systems. At high acceptor concentrations, Pda depends linearly on C2 consistent with the Fong and Diestler theory of energy transfer. However, at low acceptor concentrations the observations of time evolutions of Tb3+ luminescence decay following flash excitation has enabled us to examine diffusion limited energy transfer from Tb3+ to Nd3+ and Tb3+ to Ho3+ in DMSO. 相似文献
147.
Wiedeking M Tabor SL Pavan J Volya A Aguilar AL Calderin IJ Campbell DB Cluff WT Diffenderfer E Fridmann J Hoffman CR Kemper KW Lee S Riley MA Roeder BT Teal C Tripathi V Wiedenhöver I 《Physical review letters》2005,94(13):132501
Excited states in 20O were populated in the reaction 10Be(14C,alpha) at Florida State University (FSU). Charged particles were detected with a particle telescope consisting of 4 annularly segmented Si surface barrier detectors and gamma radiation was detected with the FSU gamma detector array. Five new states were observed below 6 MeV from the alpha-gamma and alpha-gamma-gamma coincidence data. Shell model calculations suggest that most of the newly observed states are core-excited 1p-1h excitations across the N=Z=8 shell gap. Comparisons between experimental data and calculations for the neutron-rich O and F isotopes imply a steady reduction of the p-sd shell gap as neutrons are added. 相似文献
148.
Hanna TA Ghosh AK Ibarra C Zakharov LN Rheingold AL Watson WH 《Inorganic chemistry》2004,43(24):7567-7569
Molybdenum monooxo compoundsMoO(OAr)4-nCln (n=0-2, Ar=2,6-Me2C6H3 or 2,6-i-Pr2C6H3) have been synthesized starting from the dioxo precursor MoO2Cl2. The complexes are characterized spectroscopically and by X-ray diffraction. The formation mechanism likely involves phenol precoordination followed by addition across the Mo=O bond. 相似文献
149.
We propose and demonstrate a simple technique for determining the M/# parameter of a holographic recording material. In this method, divergent object and reference beams are used to produce a spatially varying index modulation. One can analyze the resultant diffraction pattern to find M/# by using only a single grating; existing techniques require many gratings. 相似文献
150.
Shahriar MS Tripathi R Kleinschmit M Donoghue J Weathers W Huq M Shen JT 《Optics letters》2003,28(7):525-527
We describe a superparallel holographic optical correlator that performs two-dimensional spatial and angular multiplexing simultaneously. The key step in this architecture is the use of a holographic multiplexer to split a query image into many copies before it applies them to the holographic database. A holographic demultiplexer, in conjunction with an aperture, is used to identify the location and the angle of the brightest correlation peak. This architecture uses only O(square root of N) detector elements to search through N unsorted images in a single query. We demonstrate the basic features of this architecture, using three spatial locations with eight angle-multiplexed images in each location. 相似文献