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101.
This work is concerned with rigid-plastic limit analysis of shells of revolution subject to rotationally symmetric loadings. These shells, of arbitrary shape, are discretized into a series of finite elements, each being a conical shell. The von Mises condition, valid for sandwich shells, is used to compare the results obtained with existing values. After assembling the finite elements, the limit analysis program is reduced to a simple application of the non-linear programming technique where both the sequential unconstrained minimization technique (SUMT) and feasible conjugate direction (FCD) are utilized respectively for statically admissible and kinematically admissible approaches. Therefore, upper bounds and lower bounds of the collapse loads are found for some sample problems : conical, spherical, ellipsoidal, torispherical shells etc. These numerical results are illustrated and compared with existing ones described in the literature. 相似文献
102.
In this study, we report a novel and simple solution-phase route for one-dimensional metal nanocrystals. BiIn nanocrystals were prepared by directly dispersing melting BiIn alloy at an appropriate solvent. The as-obtained BiIn nanocrystals with a dendritic shape possess a good crystalline phase. The morphology of the nanocrystals can be greatly modified by changing the reaction parameters. This strong UV emission might arise from the quantum-confined In2O3 particles. 相似文献
103.
Dang Van Soa Takeo Inami Hoang Ngoc Long 《The European Physical Journal C - Particles and Fields》2004,34(3):285-289
We study the production of bileptons, new gauge bosons of lepton number two, in the minimal 3-3-1 model in high energy
collisions. If the bilepton masses are in the range of 300 GeV the reaction will give observable cross-sections in future colliders.Received: 5 August 2003, Published online: 23 March 2004Dang Van Soa: On leave of absence from Department of Physics, Hanoi University of Education, Hanoi, VietnamHoang Ngoc Long: On leave of absence from Institute of Physics, NCST, P.O. Box 429, Bo Ho, Hanoi 10000, Vietnam 相似文献
104.
Cao Thi Vi Ba Ha Huy Bang Dang Van Soa 《International Journal of Theoretical Physics》2003,42(8):1781-1786
We propose commutation relations for a single mode -deformed para-Bose oscillator. In this new deformation of para-Bose statistics the distribution function has the same form as in the para-Bose statistics. Furthermore, we show analogies between the coherent states of -deformed and q-deformed para-Bose statistics. 相似文献
105.
A simplicial algorithm is proposed for computing an integer point of a convex set
CRn
satisfying
with
The algorithm subdivides R
n into integer simplices and assigns an integer labelto each integer point of R
n. Starting at an arbitraryinteger point, the algorithm follows a finite simplicial path that leads either to an integer point of C or to the conclusion that C has no integer point. 相似文献
106.
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108.
The work strengthens the result established by L. Cohen on uncertainty principle involving phase derivative. We propose stronger uncertainty principles not only in the classical setting for Fourier transform, but also for self-adjoint operators. We also deduce the conditions that give rise to the equal relation of the uncertainty principle. Examples are provided to show that the new uncertainty principle is truly sharper than the existing ones in literature. 相似文献
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