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71.
T. T. Nguyen A. K. Gupta Y. Wang 《Annals of the Institute of Statistical Mathematics》1996,48(3):573-576
For independent random variables X and Y, define % MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqefm0B1jxALjhiov2D% aebbfv3ySLgzGueE0jxyaibaiGc9yrFr0xXdbba91rFfpec8Eeeu0x% Xdbba9frFj0-OqFfea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs% 0dXdbPYxe9vr0-vr0-vqpWqaaeaabiGaciaacaqabeaadaqaaqGaaO% qaaiaabofaruWrL9MCNLwyaGqbciaa-bcacqGHHjIUcaWFGaGaa8hw% aiaa-TcacaWFzbaaaa!4551!\[{\rm{S}} \equiv X + Y\]. When the conditional expectations % MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqefm0B1jxALjhiov2D% aebbfv3ySLgzGueE0jxyaibaiGc9yrFr0xXdbba91rFfpec8Eeeu0x% Xdbba9frFj0-OqFfea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs% 0dXdbPYxe9vr0-vr0-vqpWqaaeaabiGaciaacaqabeaadaqaaqGaaO% qaaiaadweacaGGBbqefCuzVj3zPfgaiuGajaaqcaWFNbGccaGGOaGa% amiwaiaacMcacaGG8bGaam4uaiaac2facqGHHjIUcaWGHbGaaiikai% aadofacaGGPaaaaa!4BC4!\[E[g(X)|S] \equiv a(S)\]and % MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqefm0B1jxALjhiov2D% aebbfv3ySLgzGueE0jxyaibaiGc9yrFr0xXdbba91rFfpec8Eeeu0x% Xdbba9frFj0-OqFfea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs% 0dXdbPYxe9vr0-vr0-vqpWqaaeaabiGaciaacaqabeaadaqaaqGaaO% qaaiaadweacaGGBbGaamiAaiaacIcacaWGybGaaiykaiaacYhacaWG% tbGaaiyxaiabggMi6kaadkgacaGGOaGaam4uaiaacMcaaaa!4894!\[E[h(X)|S] \equiv b(S)\]are given, then under certain assumptions, the density function of X has the form of u(x)k()eax, where u(x) is uniquely determined by the functions a(·) and b(·). 相似文献
72.
73.
Van On Vo Tran Dzung Tri Nguyen Chi Linh Phan Khiem Hong 《The European Physical Journal C - Particles and Fields》2022,82(3):1-12
The European Physical Journal C - Considering supergravity theory is a natural step in the development of gravity models. This paper follows the “algebraic“ path and constructs possible... 相似文献
74.
Continuous scanning of a 1 GHz pulsed laser line using only one 5-cm grating as an intracavity selective element is obtained from a pulsed dye laser pumped by a Nd: YAG (8 ns-532 nm) laser. Such a single-grating dye laser operates in the same way as a real double-grating grazing incidence laser and provides an appreciable improvement of the resolution (enhancement factor 2), compared with previous grazing incidence ones. The superiority of this laser cavity has been proved for single-longitudinal-mode operation.Laboratoire associé à l'Université de Paris-Sud 相似文献
75.
Shi W Petersen EB Nguyen DT Yao Z Chavez-Pirson A Peyghambarian N Yu J 《Optics letters》2011,36(18):3575-3577
We report a unique all fiber-based single-frequency Q-switched laser in a monolithic master oscillator power amplifier configuration at ~1920 nm by using highly Tm-doped germanate fibers for the first time. The actively Q-switched fiber laser seed was achieved by using a piezo to press the fiber in the fiber Bragg grating cavity and modulate the fiber birefringence, enabling Q-switching with pulse width and repetition rate tunability. A single-mode polarization maintaining large core 25 μm highly Tm-doped germanate fiber was used in the power amplifier stage. For 80 ns pulses with 20 kHz repetition rate, we achieved 220 μJ pulse energy, which corresponds to a peak power of 2.75 kW with transform-limited linewidth. 相似文献
76.
Ngo Ngoc Ha Nguyen Truong Giang Tran Ngoc Khiem Nguyen Duc Dung Tom Gregorkiewicz 《固体物理学:研究快报》2016,10(11):824-827
Photogenerated carriers in Si–Ge alloy nanocrystals (NCs) prepared by co‐sputtering method were investigated by mean of transient induced absorption. The carrier relaxation features multiple components, with three decay life times of τ ≈ 600 fs, 12 ps, and 15 ns, established for Si0.2Ge0.8 alloy NCs of a mean crystal size of 9 nm and standard deviation of 3 nm. Deep carrier traps, identified at the boundary between the NCs and the SiO2 host with the ionization energy of about 1 eV, are characterized by a long‐range Coulombic potential. These are responsible for rapid depletion of free carrier population within a few picoseconds after the excitation, which explains the low emissivity of the investigated materials, and also sheds light on the generally low luminescence of Si/Ge and Ge NCs. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
77.
Aguilar-Arevalo AA Anderson CE Brice SJ Brown BC Bugel L Conrad JM Dharmapalan R Djurcic Z Fleming BT Ford R Garcia FG Garvey GT Mirabal J Grange J Green JA Imlay R Johnson RA Karagiorgi G Katori T Kobilarcik T Linden SK Louis WC Mahn KB Marsh W Mauger C Metcalf W Mills GB Moore CD Mousseau J Nelson RH Nguyen V Nienaber P Nowak JA Osmanov B Pavlovic Z Perevalov D Polly CC Ray H Roe BP Russell AD Schirato R Shaevitz MH Sorel M Spitz J Stancu I Stefanski RJ Tayloe R Tzanov M Van de Water RG 《Physical review letters》2010,105(18):181801
The MiniBooNE experiment at Fermilab reports results from a search for ˉν_{μ}→ˉν_{e} oscillations, using a data sample corresponding to 5.66×102? protons on target. An excess of 20.9±14.0 events is observed in the energy range 475相似文献
78.
Luc Huy Hoang Nguyen T. M. Hien W. S. Choi Y. S. Lee K. Taniguchi T. Arima S. Yoon X. B. Chen In‐Sang Yang 《Journal of Raman spectroscopy : JRS》2010,41(9):1005-1010
We have measured polarized Raman spectra of MnWO4 single crystals at low temperatures, and studied the temperature dependence of the various phonon modes. From our Raman studies of the MnWO4, a new transition temperature, ∼180 K, was found. We have completely assigned the symmetries of the 18 observed Raman modes of the MnWO4, as expected from a group theoretical analysis. These Raman modes have been classified into three groups according to weak, intermediate and strong temperature dependence of the modes in each group. Six internal modes have been identified by their weak temperature dependence of the Raman wavenumbers. The temperature dependence of the wavenumbers of the Bg modes in Mg O bonds, modes of intermediate temperature dependence group, shows an anomalous behavior under 50 K. The phonon modes of strong temperature dependence show an anomalous change at ∼180 K in the linewidths. This is believed to be a new transition temperature which involves the changes in the inter‐WO6 octahedra structure. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
79.
M.D. Stewart Jr. H.Q. Nguyen S.M. Hollen Aijun Yin J.M. Xu J.M. Valles Jr. 《Physica C: Superconductivity and its Applications》2009,469(13):774-777
We have measured the thickness dependence of the superconducting critical temperature, Tc(dBi), in amorphous Bi/Sb films patterned with a regular array of holes as well as nanoscale thickness variations. We find that the mean field Tc is suppressed relative to simultaneously produced unstructured films of the same thickness. Surprisingly, however, the functional form for Tc(dBi), remains unaffected. The role of the thickness variations in suppressing Tc is compared to the role of the holes, through parameterization of the surface, as measured through AFM/SEM and a proximity effect calculation. These results suggest that these two nanoscale modifications suppress Tc about equally and are consistent with Tc being determined on a microscopic length scale. 相似文献
80.
Nanosized luminescent (Y,Bi)VO4:Eu3+ and Y(V,P)O4:Eu3+ were synthesized at low temperatures either by a coprecipitation method or by a hydrothermal method from aqueous solutions. The effect of Bi3+ ion or P5+ ion content in the lattice, annealing temperature effects on the crystal structure and the particle size, and the luminescence property of (Y,Bi)VO4:Eu3+ and Y(V,P)O4:Eu3+ nanoparticles were examined with a field-enhanced scanning electron microscopy, XRD, and a spectrofluorometer. The pristine YVO4:Eu3+, (Y,Bi)VO4:Eu3+, or Y(V,P)O4:Eu3+ nanoparticles are 35-50 nm in size. The luminescence spectrum of the Eu3+ ion was used to probe its position in the crystal lattice. The dopant ions enter the same lattice sites in the nanocrystalline as in the corresponding bulk material, resulting similar spectral features between them. Photoluminescence intensity is weak for the pristine nanoparticles. Annealing the nanoparticles at temperatures up to 1000 °C results in the increased luminescence intensity (>80% of micrometer-sized phosphors) with the minimal particle growth and the improved particle crystallinity. 相似文献