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531.
State-space models are used for modeling of many physical and economic processes. An asymptotic distribution theory for the state estimate from a Kalman filter in the absence of the usual Gaussian assumption was presented by Spall and Wall (1984). They proved the central limit theorem for state estimators when the random terms in the model have arbitrary distribution. In this study, some convergence rates in the central limit theorem are given. These convergence rates are used for the development of a nonparametric test of the validity of the model 相似文献
532.
Summary
Radiation-induced graft polymerization of N,N-dimethylaminoethylmethacrylate (DMAEMA) from solutions in carbon tetrachloride
or in chloroform onto bisphenol A-derived polycarbonate (PC-1) and allyl diglycol carbonate (PC-2), respectively, was carried
out by method of preirradiation in air. It has been found essential difference in transparency and durability of the modified
PC-1 and PC-2. Effects of preirradiation dose as well as temperature and time of graft polymerization on effectiveness of
DMAEMA grafting onto PC-2 were investigated, the optimal values of dose and temperature are 500 kGy and 55°C, respectively.
Received: 6 June 1999/Revised version: 9 September 1999/Accepted: 9 September 1999 相似文献
533.
Thermal transport in MWCNT sheets and yarns 总被引:2,自引:0,他引:2
Ali E. Aliev Csaba Guthy Mei Zhang Shaoli Fang Anvar A. Zakhidov John E. Fischer Ray H. Baughman 《Carbon》2007,45(15):2880-2888
Laser flash and self-heating 3ω techniques were employed to determine the anisotropic thermal conductivity and thermal diffusivity of a highly oriented, free-standing multiwalled carbon nanotube (MWCNT) sheet and a yarn drawn from a sidewall of the MWCNT forest grown by chemical-vapor deposition. Normalized to ideal high density structure the thermal conductivity and the thermal diffusivity along the alignment are 50 ± 5 W/m K and 45 ± 5 mm2/s, respectively, and are mostly limited by dangling terminals of bundles, intrinsic defects of individual nanotubes and phonon scattering within the bundles, which form the supporting matrix of the MWCNT sheet. The high degree of tube–tube overlap substantially decreases the electrical and thermal interconnection resistance, which usually dominates in randomly deposited mat-like nanotube assemblies. The extremely high surface area of the MWCNT sheet leads to excessive radial heat radiation that does not allow transferring the heat energy along the MWCNT sheet by means of phonons to distances >2 mm. On the other hand, the high surface area and negligible heat capacitance make it a perfect material for bolometric sensing (r = 38 V/W) and heat dissipation. 相似文献