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61.
Deployment of cellular networks involves substantial capital investment. Competition motivates service providers to minimize these costs while maintaining service quality. We develop a cost-minimizing planning model that simultaneously determines three important variables – base station location, power level and frequency group assignments for the antennas at each selected base station. It can represent different antenna configurations and frequency groups commonly used in practice. The integer-programming problem is solved using a Lagrangian relaxation based heuristic and computational tests indicate good solution quality for reasonably large problems. We also note the appropriate role of such optimization models in the overall planning process. 相似文献
62.
63.
This report summarises the work done in the ‘Beyond the Standard Model’ working group of the Sixth Workshop on High Energy
Physics Phenomenology (WHEPP-6) held at the Institute of Mathematical Sciences, Chennai, Jan 3–15, 2000. The participants
in this working group were: R Adhikari, B Ananthanarayan, K P S Balaji, Gour Bhattacharya, Gautam Bhattacharyya, Chao-Hsi
Chang (Zhang). D Choudhury, Amitava Datta, Anindya Datta, Asesh K Datta, A Dighe, N Gaur, D Ghosh, A Goyal, K Kar, S F King,
Anirban Kundu, U Mahanta, R N Mohapatra, B Mukhopadhyaya, S Pakvasa, P N Pandita, M K Parida, P Poulose, G Raffelt, G Rajasekaran,
S Rakshit, Asim K Ray, A Raychaudhuri, S Raychaudhuri, D P Roy, P Roy, S Roy, K Sridhar and S Vempati. 相似文献
64.
65.
66.
The crystallization behaviour and evolution of nanoparticles in amorphous Al-Ni-Mischmetal (Mm) and Al-Ni-La alloys during
heat treatment have been studied. Rapidly solidified ribbons were obtained by induction melting and ejecting the melt onto
a rotating Cu wheel in an Ar atmosphere.
The crystallization behaviour of the melt-spun ribbons was investigated using differential scanning calorimetry and X-ray
diffractometry (XRD). XRD studies confirmed that all the ribbons were fully amorphous. Al-Ni-Mm systems showed a three-stage
crystallization process whereas Al-Ni-La system, in general, showed a two-stage crystallization process on annealing. Crystallization
kinetics was analysed by Kissinger and Johnson-Mehl-Avrami approaches. In Al-Ni-La alloys, the crystallization pathways depend
on the La concentration. Microhardness of all the ribbons was examined at different temperatures and correlated with the corresponding
evolution of phases. 相似文献
67.
68.
We extend the Clauser-Horne formulation of Bell-type inequality for the correlated pair of decaying and oscillating (neutral pseudo-scalar) meson-antimesons, using a few supplementary assumptions. The quantum-mechanical predictions for the B0- \(\bar B^0 \) system do lead to violations of this inequality under certain conditions. Further work is called for to investigate the possibility of dispensing with the supplementary assumptions. 相似文献
69.
Urea and thiourea based receptors 1 and 2 bind H2PO4−, OH−, CH3CO2−, and PhCO2− ions in an acetonitrile/DMSO (9:1, v/v) medium. Binding of these anions causes an appreciable change in the visible region of the spectrum, which can be detected by the naked eye. The affinity constant for H2PO4− is higher by about an order of magnitude as compared to the other oxyanions mentioned above. Ab initio calculations predicted tweezer-like binding modes for receptors 1 and 2 with these anions and a higher affinity toward H2PO4− was predicted in acetonitrile. 相似文献
70.
Summary In acid perchlorate media, the title complex undergoes intramolecular redox decomposition generating ultimately Ag+ ion and oxidation products of the ligand. The reaction follows a simple first-order process, and the observed pseudo-first-order rate constant is given by kobs=k0+kKa/[H+] where Ka is the deprotonation constant of the parent complex; pKa is approximately 5.9 at 30°. The values of 105 k0(s–1) and 107 kKa (Ms–1) at 30°, I=1.0 M, are 9.3±0.1 and 11.8±1.3; corresponding H (kJ/mol), S (JK–1 M–1) values are 105±0.5, 23±1 and 79±8,-96±5, respectively. The results are compared with those for similar reaction of (ethylenebisbiguanide)silver(III) and effect of change in ligand structure on kinetic behaviours of these complexes is discussed. 相似文献