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51.
Kellie Brown John Cameron John Stears Wayne Hicky Roger Cormier Xiaoyi Bao Liang Chen 《Fiber and Integrated Optics》2013,32(5):427-442
With OC-192 communications systems being commercially available and higher bit rate systems in development, prudent telecommunications network administrators are testing their installed fibers to determine if they can be successfully used at 10 Gb/s and higher. Together with New Brunswick Telephone (NBTel), the Fiber Optics Group at UNB have tested various installed fibers and cables in the NBTel network for their losses at wavelengths of 1244, 1310, 1550, and 1625 nm, as well as for strain and polarization mode dispersion (PMD). Weather conditions, age, place of installation, and cable types have also been considered. Aging does not seem to affect the performance of the fibers. Although most fibers are high-speed system compatible when looking at attenuation measurements, about 40% of the fibers tested would not meet the 10 Gb/s OC-192 system manufacturer's design guidelines concerning PMD. 相似文献
52.
Adams J Aggarwal MM Ahammed Z Amonett J Anderson BD Arkhipkin D Averichev GS Badyal SK Bai Y Balewski J Barannikova O Barnby LS Baudot J Bekele S Belaga VV Bellwied R Berger J Bezverkhny BI Bharadwaj S Bhasin A Bhati AK Bhatia VS Bichsel H Billmeier A Bland LC Blyth CO Bonner BE Botje M Boucham A Brandin AV Bravar A Bystersky M Cadman RV Cai XZ Caines H Calderón de la Barca Sánchez M Castillo J Cebra D Chajecki Z Chaloupka P Chattopadhyay S Chen HF Chen Y Cheng J Cherney M Chikanian A 《Physical review letters》2005,94(6):062301
Midrapidity open charm spectra from direct reconstruction of D0(D0)-->K-/+pi+/- in d+Au collisions and indirect electron-positron measurements via charm semileptonic decays in p+p and d+Au collisions at squareroot[sNN]=200 GeV are reported. The D0(D0) spectrum covers a transverse momentum (pT) range of 0.1相似文献
53.
Andrew R. Cormier Carl B. Dietrich Jeremy Price Jeffrey H. Reed 《Physical Communication》2010,3(2):73-80
The software defined radio (SDR) has opened the doors for levels of radio reconfiguration not possible through the use of more traditional radio design approaches. While most radios allow variation of parameters such as carrier frequency, an SDR enables large-scale reconfiguration (e.g., changing to a different protocol type or MAC). In this research, we explore automated, dynamic large-scale radio reconfiguration through the implementation and characterization of three alternative reconfigurable radio designs. These implementations seek to quantify the impacts of implementing large-scale radio reconfiguration through SDR application management enabled by the Software Communications Architecture (SCA) and similar SDR architectures. The SCA, a widely used SDR standard developed by the US Department of Defense, primarily supports static configurations with infrequent reconfiguration. However, we present a novel approach that uses features of the SCA and its enabling technologies to achieve rapid dynamic reconfiguration of SDRs. The act of radio reconfiguration through SCA application management is found to momentarily decrease the radio throughput. Although some overhead is experienced in the demonstration systems, the methods discussed achieve a high degree of flexibility through the use of standard SDR architectures. 相似文献
54.
Adler C Ahammed Z Allgower C Amonett J Anderson BD Anderson M Averichev GS Balewski J Barannikova O Barnby LS Baudot J Bekele S Belaga VV Bellwied R Berger J Bichsel H Bland LC Blyth CO Bonner BE Bossingham R Boucham A Brandin A Cadman RV Caines H Calderón De La Barca Sánchez M Cardenas A Carroll J Castillo J Castro M Cebra D Chattopadhyay S Chen ML Chen Y Chernenko SP Cherney M Chikanian A Choi B Christie W Coffin JP Conin L Cormier TM Cramer JG Crawford HJ DeMello M Deng WS Derevschikov AA 《Physical review letters》2001,87(8):082301
Two-pion correlation functions in Au+Au collisions at square root of [s(NN)] = 130 GeV have been measured by the STAR (solenoidal tracker at RHIC) detector. The source size extracted by fitting the correlations grows with event multiplicity and decreases with transverse momentum. Anomalously large sizes or emission durations, which have been suggested as signals of quark-gluon plasma formation and rehadronization, are not observed. The Hanbury Brown-Twiss parameters display a weak energy dependence over a broad range in square root of [s(NN)]. 相似文献
55.
Soreni N Noseworthy MD Cormier T Oakden WK Bells S Schachar R 《Magnetic resonance imaging》2006,24(2):187-194
PURPOSE: To measure possible positional and diurnal physiological effects on brain metabolites in single-voxel proton magnetic resonance spectroscopy ((1)H-MRS) measurements of the right and left striatum. METHODS: (1)H-MRS measurements were performed in 10 healthy adult volunteers using a short echo PRESS sequence (TE=30 ms, TR=3000 ms). Each individual was scanned during both morning and afternoon hours. Regions of interest were right and left striatum. To control for systematic drift in scanner performance, (1)H-MRS measurements of a standard phantom solution were also acquired. Statistical analysis was performed using a repeated measures analysis of variance that included three within-subject factors: metabolite (N-acetyl-aspartate [NAA] or creatine [Cr]), laterality (left or right caudate) and time (morning or afternoon). RESULTS: A significant interaction (P<.016) between time of day and metabolite levels was observed. Further exploration of this finding revealed a significant difference between morning and afternoon levels of NAA (P<.044) but not Cr. In addition, no significant morning-to-afternoon differences were observed for the (1)H-MRS phantom measurements. CONCLUSIONS: Systematic variation due to scanner performance does not account for the changes observed in repeated measurements of striatal NAA levels. This difference may be accounted for by either repositioning effects or circadian physiological effects. Further studies are required to learn whether time of day standardization of (1)H-MRS acquisitions may contribute to improved reproducibility of measurements. 相似文献
56.
Ferlat G Charpentier T Seitsonen AP Takada A Lazzeri M Cormier L Calas G Mauri F 《Physical review letters》2008,101(6):065504
We investigate the structural and vibrational properties of glassy B2O3 using first-principles molecular dynamics simulations. In particular, we determine the boroxol rings fraction f for which there is still no consensus in the literature. Two numerical models containing either a low or a high level of boroxol rings are tested against a gamut of experimental probes (static structure factor, Raman, 11B and 17O NMR data). We show that only the boroxol-rich model (f=75%) can reproduce the full set of observables. Total-energy calculations show that at the glass density, boroxol-rich structures are favored by about 6 kcal/(mol boroxol). Finally, the liquid state is explored in the 2,000-4,000 K range and a reduction of f to 10%-20% is obtained. 相似文献
57.
M. Blanchard M. Cormier R. Tremblay J.L. Lachambre P. Lavigne F. Rheault 《Optics Communications》1976,18(3):274-278
We have observed the 4.3 μm fluorescence signal produced by a superatmospheric double-discharge CO2 laser, up to a pressure of 5 atm. The evolution of the signal amplitude with pressure reveals an unusual behaviour which we associate to the hot bands. Moreover, we have deduced the V-V relaxation times of CO2 in mixtures CO2:N2:He of (10:5:85) and CO2:He of (9:91). 相似文献
58.
Russell A. Cormier 《Tetrahedron letters》1980,21(21):2021-2024
59.
Adams J Adler C Aggarwal MM Ahammed Z Amonett J Anderson BD Arkhipkin D Averichev GS Bai Y Balewski J Barannikova O Barnby LS Baudot J Bekele S Belaga VV Bellwied R Berger J Bezverkhny BI Bharadwaj S Bhatia VS Bichsel H Bland LC Blyth CO Bonner BE Botje M Boucham A Brandin A Bravar A Cadman RV Cai XZ Caines H Calderón de la Barca Sánchez M Carroll J Castillo J Cebra D Chaloupka P Chattopdhyay S Chen HF Chen Y Cheng J Cherney M Chikanian A Christie W Coffin JP Cormier TM Cramer JG Crawford HJ 《Physical review letters》2004,92(18):182301
The transverse mass spectra and midrapidity yields for Xis and Omegas are presented. For the 10% most central collisions, the (-)Xi(+)/h(-) ratio increases from the Super Proton Synchrotron to the Relativistic Heavy Ion Collider energies while the Xi(-)/h(-) stays approximately constant. A hydrodynamically inspired model fit to the Xi spectra, which assumes a thermalized source, seems to indicate that these multistrange particles experience a significant transverse flow effect, but are emitted when the system is hotter and the flow is smaller than values obtained from a combined fit to pi, K, p, and Lambdas. 相似文献
60.
In this paper, a dynamic programming model is developed for the purpose of establishing a warehouse capacity expansion schedule and underlying multi-item inventory policy that are jointly optimal. The optimal warehouse size over any segment of the planning horizon is obtained by solving a nonlinear optimisation problem, this being accomplished efficiently by exploiting the Kuhn–Tucker conditions. Repeating this procedure between each pair of time periods results in a discrete state space, so that the optimal capacity expansion schedule corresponds to a shortest path in a network. Managerial insights are provided through experimentation with the model. 相似文献