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151.
Rahul?BasuEmail author K.?Sridhar 《The European Physical Journal C - Particles and Fields》2004,34(3):367-369
Dilepton production in heavy ion collisions in the intermediate mass region (IMR) has consistently shown an excess over theoretical estimates. An attempt to understand this discrepancy between the observed dilepton pairs and the theoretical estimate is made here through the production of the
meson and estimates obtained by NRQCD calculations. We find that
production offers a satisfactory quantitative picture for explaining the discrepancy.Received: 13 August 2003, Revised: 9 February 2004, Published online: 23 March 2004 相似文献
152.
We present a conjecture relating the density of quantum resonances for an open chaotic system to the fractal dimension of the associated classical repeller. Mathematical arguments justifying this conjecture are discussed. Numerical evidence based on computation of resonances of systems of n disks on a plane are presented supporting this conjecture. The result generalizes the Weyl law for the density of states of a closed system to chaotic open systems. 相似文献
153.
Statistical properties of experimental eigenfunctions of quantum chaotic and disordered microwave cavities are shown to demonstrate nonuniversal correlations due to localization. Varying energy E and mean free path l enable us to experimentally tune from localized to delocalized states. Large level-to-level inverse participation ratio ( I2) fluctuations are observed for the disordered billiards, whose distribution is strongly asymmetric about . The spatial density autocorrelations of eigenfunctions are shown to spatially decay exponentially and the decay lengths are experimentally determined. All the results are quantitatively consistent with calculations based upon nonlinear sigma models. 相似文献
154.
155.
The dynamic analogue of the von Karman equations is used to study the forced response, including asymmetric vibrations and traveling waves, of a clamped circular plate subjected to harmonic excitations when the frequency of excitation is near one of the natural frequencies. The method of multiple scales, a perturbation technique, is used to solve the non-linear governing equations. The approach presented provides a great deal of insight into the nature of the non-linear forced resonant response. It is shown that in the absence of internal resonance (i.e., a combination of commensurable natural frequencies) or when the frequency of excitation is near one of the lower frequencies involved in the internal resonance, the steady state response can only have the form of a standing wave. However, when the frequency of excitation is near the highest frequency involved in the internal resonance it is possible for a traveling wave component of the highest mode to appear in the steady state response. 相似文献
156.
A general procedure is presented to determine the natural frequencies and mode shapes of nearly annular and circular plates. A straightforward perturbation procedure is used with a transfer of the boundary conditions to obtain solutions given by simple expressions. As well as yielding good accuracy quantitatively, the method accurately predicts qualitative behavior. Numerical results are presented for clamped elliptical and square plates. 相似文献
157.
[structure: see text] A synthesis of arylnaphthoquinone 22 corresponding to the CD-D' unit of angelmicin B via the Suzuki coupling of the D' arylboronic acid 15 with the CD bromonaphthoquinone 21 is described. The mild conditions for the Suzuki cross-coupling leading to 22 may prove to be useful for the eventual late-stage coupling of the two highly functionalized halves of angelmicin B. 相似文献
158.
We develop a method to determine the topology of a network that interconnects a number of token rings using source routing bridges. The purpose is to compute a topology that provides low response delays for network users at a minimal cost of bridge installations. We formulate this network design problem as a mixed binary integer linear program. We develop effective heuristic algorithms. The algorithms exploit the topology and routing solutions of the linear programming relaxation in a sophisticated manner which we believe is new in the literature. The model incorporates performance issues, such as network stability, bridge overflow, back pressure effect and broadcast storm, that are specific to the underlying communication technology. By formally incorporating these performance issues, we tighten the model formulation and improve the quality of the LP bound considerably. Computational results are reported for problems with up to 20 token rings and 190 potential bridge locations. 相似文献
159.
Debajyoti Choudhury Rahul Sinha S Arunagiri Gautam Bhattacharyya Debrupa Chakraverty Debajyoti Choudhury Amitava Datta Anindya Datta Aseskrishna Datta Amol Dighe Dilip Kumar Ghosh Anjan Giri Stephen King Anirban Kundu Rukmani Mohanta Biswarup Mukhopadhyaya Sreerup Raychaudhuri Saurabh Rindani Probir Roy DP Roy Sourov Roy AI Sanda Nita Sinha Rahul Sinha K Sridhar H Yamamoto 《Pramana》2000,55(1-2):335-345
This report summarises the work done during WHEPP-6 (Institute of Mathematical Sciences, Chennai, India, Jan 3–15, 2000) in
Working group on ‘B and collider physics’. 相似文献
160.
Dongamanti Ashok Aamate Vikas Kumar Devulapally Mohan Gandhi Gundu Srinivas Balabadra Saikrishna Manga Vijjulatha Yogeeswari Perumal Sriram Dharmarajan Balasubramanian Sridhar 《Molecular diversity》2017,21(4):999-1010
Molecular Diversity - On the basis of reported antimycobacterial property of chroman-4-one pharmacophore, a series of chemically modified bis-spirochromanones were synthesized starting from... 相似文献