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641.
Hakan Deliç 《Signal processing》1997,60(3):281-288
We consider a distributed system where sensors make location parameter estimates using their observations. A central processor collects the local estimates and declares a final estimate based on them. We present a simple study of the convergence properties of three structures where empirical mean and M-estimates are used in various combinations. It is shown that when occasional outliers exist, decentralized estimators that provide robustness at stages where data corruption occurs perform superiorly. 相似文献
642.
利用具有非线性光学活性的对硝基苯胺掺杂高玻璃化转变温度的聚芳醚砜(PES-C)和聚芳醚酮(PEK-C),得到了两种掺杂含量较高的掺杂型非线性光学聚合物体系。电晕极化表明较高的取向和较慢的松驰。 相似文献
643.
Summary The kinetics of oxygen-transfer from [MoO2(Et-L-cys)2] to PPh3 and the reaction between [Mo2O3(Et-L-cys)4] and O2 in benzene solution have been investigated using spectrophotometric techniques between 25 and 40°. The rate laws-d[Mo6+]/dt = k1[Mo6+][PPh3] with k1 (at 35°) = 2.95×10–4dm3mol–1s–1 and -d[Mo5+]/dt = 2k3[Mo5+][O2] with k3 (at 35°) = 6.3×10–2 dm3mol–1s–1 account for the kinetic data obtained with activation parameters (at 35°) of H = 46 kJ mol–1, S = –153 JK–1mol–1, and H = 50.8 kJ mol–1, S = –95 JK–1 mol–1 respectively. 相似文献
644.
二阶非线性光学极化聚合物 总被引:3,自引:2,他引:3
本文综述了二阶非线性光学极化聚合物材料研究概况,包括器件对材料的要求、材料的研究进展及目前存在的问题。 相似文献
645.
A novel series of thiourea derivatives, namely, N,N-diphenyl-N-(4-phenyl-benzoyl)thiourea (HL1), N,N-diphenyl-N-(4-chloro-benzoyl)thiourea (HL2) and N,N-di-n-propyl-N-(4-chloro-benzoyl)thiourea (HL3), and its metal complexes has been prepared and characterised by elemental analysis, i.r. spectroscopy, 1H-n.m.r. spectroscopy, mass spectrometry and single crystal X-ray diffraction. The ligand coordinates to NiII, CuII and CoII in a bidentate manner yielding essentially neutral complexes of the type cis-[ML2]. N.m.r. spectra and single crystal X-ray diffraction analysis revealed the presence of a distorted tetrahedral coordination ML2 complex. 相似文献
646.
Pter Molnr Jzsef Deli Erzsbet sz Zoltn Matus Gyula Tth Ferenc Zsila 《Helvetica chimica acta》2004,87(8):2169-2179
3′‐Epilutein (=(all‐E,3R,3′S,6′R)‐4′,5′‐didehydro‐5′,6′‐dihydro‐β,β‐carotene‐3,3′‐diol; 1 ), isolated from the flowers of Caltha palustris, was submitted to both thermal isomerization and I2‐catalyzed photoisomerization. The structures of the main products (9Z)‐ 1 , (9′Z)‐ 1 , (13Z)‐ 1 , (13′Z)‐ 1 , (15Z)‐ 1 , and (9Z,9′Z)‐ 1 were determined based on UV/VIS, CD, 1H‐NMR, and MS data. 相似文献
647.
Hakan Gker Süreyya
lgen Rahmiye Ertand HÜLya Akgün Süheyla
zbey Engin Kendi GÜL Topu 《Journal of heterocyclic chemistry》1995,32(6):1767-1773
The title compounds, 1,2-dialkyl-benzimidazole-5(6)-carboxylic acids 34–45 were prepared at four steps; 1) preparation of mono amide derivatives 1–11 by the reaction of methyl 3,4-diaminobenzoate and substituted phenyl or phenoxyacetic acid chlorides; 2) preparation of the methyl benzimidazolecarboxyl-ates 12–22 , with zinc chloride and dry hydrogen chloride gas; 3) alkaline hydrolysis of the esters 23–33 ; and 4) substitution of the imidazole ring with benzyl or p-fluorobenzyl bromide, in alkali medium. 2-Aryl-benzimidazole-5(6)-carboxylic acids 50–53 were prepared via the oxidative condensation of 3,4-diaminobenzoic acid and aromatic aldehydes with cupric ion. 相似文献
648.
Complete convergence and almost sure convergence of weighted sums of random variables 总被引:6,自引:0,他引:6
Deli Li M. Bhaskara Rao Tiefeng Jiang Xiangchen Wang 《Journal of Theoretical Probability》1995,8(1):49-76
Letr>1. For eachn1, let {X
nk
, –<k<} be a sequence of independent real random variables. We provide some very relaxed conditions which will guarantee
for every >0. This result is used to establish some results on complete convergence for weighted sums of independent random variables. The main idea is that we devise an effetive way of combining a certain maximal inequality of Hoffmann-Jørgensen and rates of convergence in the Weak Law of Large Numbers to establish results on complete convergence of weighted sums of independent random variables. New results as well as simple new proofs of known ones illustrate the usefulness of our method in this context. We show further that this approach can be used in the study of almost sure convergence for weighted sums of independent random variables. Convergence rates in the almost sure convergence of some summability methods ofiid random variables are also established. 相似文献
649.
650.