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排序方式: 共有393条查询结果,搜索用时 15 毫秒
91.
We introduce new estimates and tests of independence in copula models with unknown margins using ?-divergences and the duality technique. The asymptotic laws of the estimates and the test statistics are established both when the parameter is an interior point or not. To cite this article: S. Bouzebda, A. Keziou, C. R. Acad. Sci. Paris, Ser. I 347 (2009). 相似文献
92.
Wagterveld RM Berendsen CW Bouaidat S Jonsmann J 《Langmuir : the ACS journal of surfaces and colloids》2006,22(26):10904-10908
We present a new and simple method to produce superhydrophobic surfaces with ultralow hysteresis. The method involves surface modification of SU-8 using an excimer laser treatment. The modified surface is coated with a hydrophobic plasma-polymerized hexafluoropropene layer. The advancing and receding water contact angles were measured to be approximately 165 degrees . The achieved water contact angle hysteresis was below the measurement limit. This low hysteresis can be ascribed to nanoscale debris generated during the excimer laser process. 相似文献
93.
94.
Salim A. Messaoudi Muhammad I. Mustafa 《Nonlinear Analysis: Theory, Methods & Applications》2010,72(9-10):3602-3611
In this paper we consider a viscoelastic equation with a nonlinear feedback localized on a part of the boundary. We establish an explicit and general decay rate result, using some properties of the convex functions. Our result is obtained without imposing any restrictive growth assumption on the damping term and strongly weakening the usual assumptions on the relaxation function. 相似文献
95.
The viscosity index (VI) and the base number (BN) of motor oils are the most important parameters to be measured in order to assess their performance and service time. Both parameters were simply obtained for virgin and recycled motor oil samples using multivariate calibration based on the FTIR data. Analysis showed that the PLS-1 has outperformed CLS and PCR for the oil parameters prediction. Five and four PLS-1 latent variables were found optimum to obtained the VI and the BN from the FTIR data; respectively. With high accuracy (99-102%) and precision (3-11%), the BN could be determined over the range 4.57-16.45 mg KOH g−1 and the VI over the range 96-153. The outputs of the PLS-1 were found comparable to those obtained by the expensive and time-consuming ASTM methods. This developed method is highly recommended for quick monitoring of the motor oil quality parameters. 相似文献
96.
Mohammad Kafini Salim A. Messaoudi Serge Nicaise 《NoDEA : Nonlinear Differential Equations and Applications》2016,23(2):13
In this paper we consider a second-order abstract evolution system with delay. We show that, under suitable conditions on the initial data and the involved functionals, the energy of solutions blows up in finite-time. We also give some concrete examples to illustrate our main result. 相似文献
97.
Mofeed Turky Rashid Mattia Frasca Abduladhem Abdulkareem Ali Ramzy Salim Ali Luigi Fortuna Maria Gabriella Xibilia 《Nonlinear dynamics》2012,68(4):555-563
Artemia larvae may show swarming organization under the presence of a light spot, while being insensitive to several other external stimuli. In this paper, the dynamics of the Artemia population in response to this kind of stimuli has been exploited to design a robot moving inside the water and able to lead the direction of the group. The robot therefore implements external leadership, by driving the Artemia population along a set of desired trajectories. Experimental results and simulations based on a model of Artemia motion confirmed the suitability of the approach. 相似文献
98.
99.
Richard A. Hollins Luiz A. Colnago Vera M. Salim Michael C. Seidl 《Journal of heterocyclic chemistry》1979,16(5):993-996
The thallation-iodination of 3-carbonylindoles ( 4a-f ) results in orientation control with substitution occurring at the 4-position ( 6a-f ). Also described is the dithallation of N-methylpyrrole-2-carboxaldehyde ( 2 ). 相似文献
100.
Mustafa M. El‐Abadelah Salim S. Sabri Monther A. Khanfar Hani A. Yasin Wolfgang Voelter 《Journal of heterocyclic chemistry》2002,39(5):1055-1059
The synthesis and spectral properties (ir, ms, nmr) of a substituted 2‐methyl‐2H‐pyrazolo[4,3‐d]‐pyrimidin‐7‐one ( 3 ), an isomer of Viagra®, are described. The key synthon, 4‐amino‐1‐methyl‐5‐propyl‐3‐pyrazolecarboxamide ( 7 ), is prepared via the reaction of ethyl 2,4‐dioxoheptanoate with methylhydrazine, followed by cyclization, nitration, amidation, and nitro group reduction. Interaction of 7 with 2‐ethoxyben‐zoyl chloride yielded the respective bis‐amide ( 8 ) which was cyclized in polyphosphoric acid to the corresponding pyrazolo[4,3‐d]pyrimidin‐7‐one derivative 9 . Chlorosulfonylation of 9 , and subsequent treatment with 1‐methylpiperazine furnished iso Viagra ( 3 ). 相似文献