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161.
Gencheng Guo Mrinal Mandal 《Signal processing》2012,92(1):170-178
Threshold systems are widely used in nonlinear signal detection. The optimal threshold and the optimal structure are crucial to obtain good performance. In this paper, we propose an efficient method to estimate optimal threshold in a threshold system based detector (TD). In addition, we investigate the structural issue of TD and propose a technique to determine the optimal structure. An optimal threshold detector is then implemented based on the optimal structure with the optimal threshold(s). Experiments show that the proposed optimal TD can be fairly compared to the optimal detection with much easier implementation and much less computational complexity. 相似文献
162.
163.
Songa Choi Jongsik Park Mrinal Kanti Kabiraz Youngmin Hong Taehyun Kwon Taekyung Kim Aram Oh Hionsuck Baik Minseop Lee Seung‐Min Paek Sang‐Il Choi Kwangyeol Lee 《Advanced functional materials》2020,30(38)
Dissolution of Ir oxides in Ir‐based catalysts, which is closely linked to the catalyst activity and stability toward the oxygen evolution reaction (OER) in acidic media, is a critical unresolved problem in the commercialization of water electrolysis. Doping foreign elements into the Ir oxides can accomplish an optimal combination of Ir oxidation states that is conducive to the leaching‐resistance of active catalytic sites. Here, it is reported that Pt doping into IrOx‐based nanoframe is beneficial in both terms of activity and stability. The Pt‐doped IrOx‐based nanoframe achieves the mass activity of 0.644 A mg?1Ir+Pt at 1.53 VRHE, which is 15‐fold higher than that of the commercial IrO2. During the accelerated durability test, the IrIV‐to‐IrIII ratio of 5 is maintained in the presence of Pt dopant to effectively mitigate the degradation of Ir catalyst, leading to the superb catalyst durability in acidic media. 相似文献
164.
Krishna C. Joshi Renuka Jain Anshu Dandia Kanti Sharma 《Journal of heterocyclic chemistry》1988,25(6):1641-1643
Reaction of 2-hydrazinobenzimidazoles with β-diketones in neutral and acidic media revealed that 2-(3,5-disubstituted-1H-pyrazol-1-yi)benzimidazoles are formed in the former case, whereas hydrazones are obtained in acidic medium. Further the alkylation of > NH of the title compound was investigated. Characterisation of these products have been done by elemental analysis, ir, pmr, 19F nmr, 13C nmr and mass spectral studies. 相似文献
165.
The self-tuning scheme for the adaptive control of a diffusion process is studied with long-run average cost criterion and maximum likelihood estimation of parameters. Asymptotic optimality under a suitable identifiability condition is established under two alternative sets of hypotheses—a Lyapunov-type stability criterion and a condition on cost which penalizes instability. 相似文献
166.
We study a zero-sum stochastic differential game in the nonnegative orthrant. The state of the system is governed by controlled reflecting diffusions in the nonnegative orthrant. We consider discounted and average payoff evaluation criteria. We prove the existence of values and optimal strategies for both payoff criteria. 相似文献
167.
Nandini Chatterjee Sudhapada Basu S. K. Palit Mrinal M. Maiti 《Journal of Polymer Science.Polymer Physics》1995,33(12):1705-1712
Thermal degradation of polyacrylonitrile (PAN) has been studied by combined differential thermal analysis, thermogravimetry, and XRD analysis. On the basis of the experimental observations, it has been suggested that the intramolecular polymerization of nitrile groups to a conjugated polyimine structure is initially limited to only the amorphous zone of PAN, which involves little evolution of off-gases. Polymerization of nitrile group in the crystalline zone starts with the melting of crystallites with the evolution of off-gases from the amorphous-crystalline zone interface. ©1995 John Wiley & Sons, Inc. 相似文献
168.
The acid catalized self condensation of 3-benzoyl-4-pbenylisocrotonicacid is described. 相似文献
169.
The total synthesis of clavosolide A, employing a radical-mediated route to build its substituted tetrahydropyran unit, a Yamaguchi reaction to construct the diolide aglycon and the Schmidt method for the final glycosidation step, revealed that the reported structure is an isomer of the natural product. 相似文献
170.
Dithizone forms stable complexes with β-alkoxycarbonyl ethyl tin chlorides (the so called “Estertins” – a unique class of PVC stabilizer). Reduction of Lewis acidity of the resulting organotin chloride can improve the efficiency of a stabilizer and therefore the β-alkoxycarbonyl ethyl tin dithizonates are likely to show PVC stabilization property. A number of β-alkoxycarbonyl ethyl tin dithizonates of the types R2SnL2, R2SnLX, and RSnL2X where R = CH3OCOCH2CH2–, C4H9OCOCH2CH2–, and CH3OCOCH(CH3)CH2–; X = Cl, SCN and L = Dithizone (i. e. 1,5-diphenyl thiocarbazone) and one complex (CH3OCOCH2CH2)2SnL′Cl where L′ = Diphenylcarbazone have been prepared and characterized by elemental analysis, electronic, IR and PMR spectral data. Possible structural features of the isolated complexes have also been discussed. Preliminary evaluation of the complex (CH3OCOCH2CH2)2Sn(HDz)2 as a PVC stabilizer has also been reported. 相似文献