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21.
We construct faithful actions of quantum permutation groups on connected compact metrizable spaces. This disproves a conjecture of Goswami. 相似文献
22.
23.
On a Problem Proposed by Kartsatos 总被引:1,自引:0,他引:1
Zhou Haiyun 《东北数学》1999,(1)
§1.IntroductionandPreliminariesLetXbearealreflexiveBanachspacewithnormandnormalizeddualitymappingJ.Asusual,wesupposethatthesp... 相似文献
24.
Study of Heat Transfer Control with Magnetic Field Using Higher Order Finite Difference Scheme 下载免费PDF全文
R. Sivakumar S. Vimala S. Damodaran & T. V. S. Sekhar 《advances in applied mathematics and mechanics.》2016,8(3):449-463
The control of convective heat transfer from a heated circular cylinder immersed
in an electrically conducting fluid is achieved using an externally imposed
magnetic field. A Higher Order Compact Scheme (HOCS) is used to solve the governing
energy equation in cylindrical polar coordinates. The HOCS gives fourth order
accurate results for the temperature field. The behavior of local Nusselt number, mean
Nusselt number and temperature field due to variation in the aligned magnetic field is
evaluated for the parameters 5≤$Re$≤40, 0≤$N$≤20 and 0.065≤$Pr$≤7. It is found that
the convective heat transfer is suppressed by increasing the strength of the imposed
magnetic field until a critical value of $N$, the interaction parameter, beyond which the
heat transfer increases with further increase in $N$. The results are found to be in good
agreement with recent experimental studies. 相似文献
25.
Given a C^*-algebra A and a comultiplication Ф on A, we show that the pair (A, Ф) is a compact quantum group if and only if the associated multiplier Hopf ^*-algebra (A, ФA) is a compact Hopf ^*-algebra. 相似文献
26.
Joško Ožbolt Josipa Bošnjak Emiliano Sola 《International Journal of Solids and Structures》2013,50(25-26):4270-4278
Compared to quasi-static loading concrete loaded by higher loading rates acts in a different way. There is an influence of strain-rate and inertia on resistance, failure mode and crack pattern. With increase of loading rate failure mode changes from mode-I to mixed mode. Moreover, theoretical and numerical investigations indicate that after the crack reaches critical velocity there is progressive increase of resistance and crack branching. These phenomena have recently been demonstrated and discussed by O?bolt et al. (2011) on numerical study of compact tension specimen (CTS) loaded by different loading rates. The aim of the present paper is to experimentally verify the results obtained numerically. Therefore, the tests and additional numerical studies on CTS are carried out. The experiments fully confirm the results of numerical prediction discussed in O?bolt et al. (2011). The same as in the numerical study it is shown that for strain rates lower than approximately 50/s the structural response is controlled by the rate dependent constitutive law, however, for higher strain rates crack branching and progressive increase of resistance is observed. This is attributed to structural inertia and not the rate dependent strength of concrete. Maximum crack velocity of approximately 800 m/s is measured before initiation of crack branching. The comparison between numerical and experimental results shows that relatively simple modeling approach based on continuum mechanics, rate dependent microplane model and standard finite elements is capable to realistically predict complex phenomena related to dynamic fracture of concrete. 相似文献
27.
H. Katsuura H. Kawamura M. Manabe H. Kawasaki H. Maeda 《Colloid and polymer science》2002,280(1):30-37
The binding of a cationic surfactant, dodecylpyridinium (C12Py) chloride, with a low-charge-density poly (methacrylic acid)
(PMA) was investigated in buffer solutions under the condition of constant pH. The binding isotherms with PMA consisted of
two and three steps at a pH lower and higher than 3.2, respectively. Bindings in the first step were independent of pH and
this step was considered to correspond to the solubilization of the hydrocarbon chains of C12Py into the nonpolar region of
the compact form of PMA. This is the indication of the compact form from the binding isotherm. At pH higher than 3.2, the
second step was discriminated and it depended on the pH. In the third step, a sharp rise in the degree of binding (β) was
observed accompanying the solubilization of the precipitates of the PMA–C12Py complex. The binding with poly(acrylic acid)
(PAA) and PMA in conventional unbuffered NaCl solutions was also examined and the pH profile of the solution during the binding
process was determined. In the case of unbuffered NaCl solutions, the binding with PAA took place cooperatively at the critical
association concentration (cac). The binding isotherm consisted of two steps and the pH decreased with the increase in β.
The binding isotherm of PMA, on the other hand, consisted of three steps: the pH decreased slightly in the first step and
considerably in the second step with the increase in β but it increased with β in the third step, exhibiting a pH minimum
around 3.2. The binding in the first step coincided with that obtained in the buffered solutions. Linear relationships between
β and the pH were found for both polymers. In the case of PMA, no cac was observed in both buffered and unbuffered NaCl solutions.
Received: 24 January 2001 Accepted: 23 May 2001 相似文献
28.
A system of reaction–diffusion equations which governs the propagation of an ozone decomposition laminar flame in Lagrangian co-ordinates is analysed by means of compact operators and modified equation methods. It is shown that the use of fourth-order accurate compact operators yields very accurate solutions if sufficient numbers of grid points are located at the flame front, where very steep gradients of temperature and species concentrations exist. Modified equation methods are shown to impose a restriction on the time step under certain conditions. The solutions obtained by means of compact operators and modified equation methods are compared with solutions obtained by other methods; good agreement is obtained. 相似文献
29.
Jianghua Fan 《Journal of Mathematical Analysis and Applications》2008,337(2):1041-1047
In this paper, we study the existence of solutions and approximation of the solutions by using a Mann type iterative scheme for variational inequalities in noncompact subsets of Banach spaces. The results presented in this paper generalize the corresponding results of J. Li [J. Li, On the existence of solutions of variational inequalities in Banach spaces, J. Math. Anal. Appl. 295 (2004) 115-126]. 相似文献
30.
该文讨论了$\a$-Bloch空间$\ba$和对数Bloch空间$\bl$之间的加权Ces\'aro算子$\tg$的有界性和紧性,给出$\tg$是$\ba$到$\bl$的有界算子或紧算子的充要条件和$\tg$是$\bl$到$\ba$的有界算子或紧算子的充要条件. 相似文献