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101.
With the advent of fiber in the loop, transmission of power ceases to be through the traditional communications medium, and the objective of powering voice lines over fiber with the same reliability goals as plain old telephone service (POTS) raises several technological, regulatory, and business issues. In order to power the optical network unit (ONU) and provide backup power for it during commercial power outages, three strategies are identified: 1) providing loop powering from a -48 volt CO/CEV power plant; 2) providing power and backup power locally, from or near the end of the loop in proximity to the OW; and 3) providing power from the curb or a power node. This paper constructs economic models to determine the worth of a watt at the 5-volt logic level at an ONU for each of the powering strategies. By normalizing all costs to the worth of a watt, comparisons can be made and appropriate architectures can be selected for various applications. 相似文献
102.
Nu Xu I. G. Bearden H. Bøggild J. Boissevain J. Dodd B. Erazmus S. Esumi C. W. Fabjan D. Ferenc D. E. Fields A. Franz J. Gaardhøje O. Hansen D. Hardtke H. van Hecke E. B. Holzer T. Humanic P. Hummel B. V. Jacak R. Jayanti M. Kaneta M. Kopytine M. Leltchouk T. Ljubicic B. Lörstad N. Maeda A. Medvedev M. Murray S. Nishimura H. Ohnishi G. Paic S. U. Pandey F. Piuz J. Pluta V. Polychronakos M. Potekhin G. Poulard A. Sakaguchi J. Simon-Gillo J. Schmidt-Sørensen W. Sondheim M. Spegel T. Sugitate J. P. Sullivan Y. Sumi W. J. Willis K. Wolf N. Xu D. S. Zachary 《Acta Physica Hungarica A》1996,4(1-4):263-270
We present recent results on single particle transverse momentum distributions of pions, kaons and protons, measured in CERN Experiment NA44, of 200 AGeV/c S+S and 158 AGeV/c Pb+Pb central collisions. By comparing these data with thermal and transport models, freeze-out parameters like the temperatureT fo and the chemical potentials (μ q ,μ s ) are extracted and discussed. 相似文献
103.
H.R. Ott H. Rudigier Z. Fisk J.O. Willis G.R. Stewart 《Solid State Communications》1985,53(3):235-237
Results of measurements of the electrical resistivity ? between 0.04 and 1 K and the specific heat cp between 0.06 and 1 K of annealed polycrystalline CeCu6 are reported. ? varies proportional to T2 below 0.1 K but is linear in T above 0.6 K. The specific heat is proportional to T below 0.5 K and the electronic specific-heat parameter . 相似文献
104.
105.
106.
M. Diakonou C. Kourkoumelis L.K. Resvanis T.A. Filippas E. Fokitis C. Trakkas A.M. Cnops E.C. Fowler D.M. Hood R.B. Palmer D.C. Rahm P. Rehak I. Stumer C.W. Fabjan T. Fields D. Lissauer I. Mannelli W. Molzon W.J. Willis 《Physics letters. [Part B]》1980,91(2):296-300
We have measured direct photon production in pp collisions at the CERN intersecting storage rings for c.m. energies 31 < √s < 63 GeV and transverse momenta up to 9GeV/c, using segmented lead/liquid-argon calorimeters. The ratio of direct photon to π0 production is significantly larger than zero, starting at pT ≈ 4 GeV/c and increasing to values of about 0.4 at 9GeV/c. No significant √s dependence is seen. 相似文献
107.
108.
Two of the stable selenenic acids reported in the literature are actually other materials. 相似文献
109.
J.H. Cobb S. Iwata R.B. Palmer D.C. Rahm I. Stumer C.W. Fabjan I. Mannelli K. Nakamura A. Nappi W. Struczinski W.J. Willis M. Goldberg N. Horwitz G.C. Moneti C. Kourkoumelis A.J. Lankford P. Rehak 《Physics letters. [Part B]》1977,68(1):101-104
The cross-section for J/ψ production in proton-proton collisions has been measured as a function of centre-of-mass energy at the CERN Intersecting Storage Rings by observing its decay into electron-positron pairs. This cross-section is found to rise by a factor of about six over the full centre-of-mass energy range from √s=23 to √s=63 GeV. Electrons resulting from this decay were identified by the use of liquid argon calorimeters and lithium foil transition radiators. Measurements of the energies of the electrons were obtained from the liquid argon calorimeters. 相似文献
110.
D. J. Cutler M. Glotin P. J. Hendra H. Jobic K. Holland Moritz M. E. A. Cudby H. A. Willis 《Journal of Polymer Science.Polymer Physics》1979,17(6):907-915
Raman spectroscopy, x-ray diffraction, and thermal analysis are used to investigate the structure of linear high-density polyethylene rapidly quenched from the melt to cryogenic temperatures. All the results point to the production of a glassy phase which crystallizes when heated above 170 K. 相似文献