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排序方式: 共有93条查询结果,搜索用时 31 毫秒
11.
Fuzzy optimization models are used to derive crisp weights (priority vectors) for the fuzzy analytic hierarchy process (AHP) based multicriteria decision making systems. These optimization models deal with the imprecise judgements of decision makers by formulating the optimization problem as the system of constrained non linear equations. Firstly, a Genetic Algorithm based heuristic solution for this optimization problem is implemented in this paper. It has been found that the crisp weights derived from this solution for fuzzy-AHP system, sometimes lead to less consistent or inconsistent solutions. To deal with this problem, we have proposed a consistency based constraint for the optimization models. A decision maker can set the consistency threshold value and if the solution exists for that threshold value then crisp weights can be derived, otherwise it can be concluded that the fuzzy comparison matrix for AHP is not consistent for the given threshold. Three examples are considered to demonstrate the effectiveness of the proposed method. Results with the proposed constraint based fuzzy optimization model are more consistent than the existing optimization models. 相似文献
12.
Abstract In this article, various issues involved in a ground-to-satellite optical communication link (i.e., acquisition time, uncertainty area, and channel noise) are discussed. Acquisition time of a free-space optical link is evaluated for coherent (sub-carrier BPSK and QPSK) and non-coherent (OOK and -PPM) modulation schemes over weak turbulent channel with transmit diversity. In the analysis, both uncorrelated and correlated beams are considered. It is seen that an increase in transmit diversity order helps to improve the acquisition time, irrespective of turbulence strength in the atmosphere. At high correlation, a marginal change in acquisition time is observed with the increase in diversity order. 相似文献
13.
A series of chalcone ligands and their corresponding vanadyl complexes of composition [VO (LI–IV)2(H2O)2]SO4 (where LI = 1,3‐Diphenylprop‐2‐en‐1‐one, LII = 3‐(2‐Hydroxy‐phenyl)‐1‐phenyl‐propenone, LIII = 3‐(3‐Nitro‐phenyl)‐1‐phenyl‐propenone, LIV = 3‐(4‐Methoxy‐phenyl)‐1‐phenyl‐propenone) have been synthesized and characterized using various spectroscopic (Fourier‐transform infrared, electrospray ionization mass, nuclear magnetic resonance, electron paramagnetic resonance, thermogravimetric analysis, vibrating sample magnetometer) and physico‐analytic techniques. Antidiabetic activities of synthesized complexes along with chalcones were evaluated by performing in vitro and in silico α‐amylase and α‐glucosidase inhibition studies. The obtained results displayed moderate to significant inhibition activity against both the enzymes by vanadyl chalcone complexes. The most potent complexes were further investigated for the enzyme kinetic studies and displayed the mixed inhibition for both the enzymes. Further, antioxidant activity of vanadyl chalcone complexes was evaluated for their efficiency to release oxidative stress using 2,2‐diphenyl‐1‐picryl‐hydrazyl‐hydrate assay, and two complexes (Complexes 2 and 4 ) have demonstrated remarkable antioxidant activity. All the complexes were found to possess promising antidiabetic and antioxidant potential. 相似文献
14.
15.
Barange DK Nishad TC Swamy NK Bandameedi V Kumar D Sreekanth BR Vyas K Pal M 《The Journal of organic chemistry》2007,72(22):8547-8550
Herein, we report transition metal-catalyzed intramolecular cyclization of o-(1-alkynyl)benzenesulfonamides to afford 3-substituted benzothiazines regioselectively via a C-N bond forming reaction and Cu-catalyzed sequential C-N and C-C bond formation leading to the corresponding 3,4-disubstituted derivatives. 相似文献
16.
The reactivity of the -C(Cl)C-CN- moiety towards an AlCl3-induced C-C bond forming reaction was investigated through the reaction of 7-chloro-5-phenyl-pyrazolo[1,5-a]pyrimidine with arenes and heteroarenes. This study furnished a novel and highly selective methodology for the preparation of 7-(hetero)aryl substituted-pyrazolopyrimidines in good to excellent yields under mild reaction conditions. 相似文献
17.
Kaushal Verma 《Mathematische Annalen》2009,344(3):645-701
Let D be a bounded domain in C
2 with a non-compact group of holomorphic automorphisms. Model domains for D are obtained under the hypotheses that at least one orbit accumulates at a boundary point near which the boundary is smooth,
real analytic and of finite type.
The author was supported by DST (India) Grant No.: SR/S4/MS-283/05 and in part by a grant from UGC under DSA-SAP, Phase IV. 相似文献
18.
Hydroxyapatite coating on stainless steel pre-coated with bovine serum albumin at ambient conditions
Nayar S Pramanick AK Sharma BK Mishra RK Bansal SK Prajapati A Sahu KK Das SK Pathak L Sinha A 《Colloids and surfaces. B, Biointerfaces》2006,48(2):183-187
A biomimetic process for coating of nanosized hydroxyapatite on stainless steel, which capitalises the dual nature of the protein bovine serum albumin in both metal binding and a strong affinity for calcium ions, has been developed. The novelty of the process lies in pre-conditioning the metallic surface using the above protein prior to its mineralization with hydroxyapatite at ambient conditions. The microporous morphology of these coatings may provide favourable solubility and resorbability as desired by many orthopaedic and orthodontic applications. 相似文献
19.
Similarity solutions are proposed for the analysis of free convection flow over a non-isothermal body of arbitrary shape embedded in porous media in the presence of internal heat generation. The porous medium is saturated with non-Newtonian power law fluid. The effect of temperature dependent viscosity on heat transfer rates is investigated. The linearized version of the Arrhenius law for temperature dependent viscosity is considered and it is shown that the heat transferred is more for a less viscous fluid. 相似文献
20.
In this paper, gold nanoparticles coated with palladium dots (Pd@Au) bimetallic nanostructures have been reported to have a peroxidase like activity which is not found in their monometallic counterparts. Based on this finding, we have developed an immunoassay in which antibody-modified Pd@Au nanostructure catalyzes the dimerization of a fluorogenic substrate for peroxidase, 3-(4-dihydroxy phenyl) propionic acid (HPPA), to generate high fluorescence signal. Specific antibodies against bensulfuron-methyl were generated by using a well characterized bensulfuron–protein conjugate as an immunogen, and the assay was performed in a competitive immunoassay format where Pd@Au nanostructure was bound to secondary antibody to show the peroxidase like activity. The developed immunoassay exhibited an excellent sensitivity showing a dynamic response range from 0.001 to 100 ng mL−1 for herbicide bensulfuron-methyl with a detection limit of 0.01 ng mL−1 (n = 3). The newly synthesized bimetallic nanostructure shows the advantages of low cost, easy synthesis and tunable catalytic activity, making it a promising substitution of enzyme peroxidase in different applications. 相似文献