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971.
In order to design nanotori for nanomechanical systems, perhaps involving oscillating components, precise physical parameters for the nanotori are necessary. Toroidal shaped molecules of carbon have been investigated previously by the present authors as constructed by connecting elbow sections formed from joining armchair and zigzag nanotubes through a pentagonal–heptagonal pair defect. In this paper, we extend this design by constructing the elbow structures from three distinct carbon nanotubes. Since for a toroidal molecule, there is a constraint on the bend angles in the elbow sections to add up to 360°, particular elbow types which can accommodate this requirement are (5,0)–(4,4)–(7,0) and (3,3)–(6,0)–(4,4). We adopt a least squares approach for the bond length to minimise the variation from the ideal carbon–carbon bond length, which is taken to be σ = 1.42 Å. Moreover, formulae for the mean generating radius of the nanotori and the mean radius of the nanotubes are obtained from certain integral expressions. This purely geometrical approach can be formally directly related to certain numerical energy minimisation methods used by a number of authors. 相似文献
972.
We determine the zeta functions of trinomial curves in terms of Jacobi sums, and obtain an explicit formula of the genus of a trinomial curve over a finite field, and we study the conditions for this curve to be a maximal curve over a finite field. 相似文献
973.
974.
975.
Selçuk Baktır Sandeep Kumar Christof Paar Berk Sunar 《Mobile Networks and Applications》2007,12(4):259-270
We propose a novel area/time efficient elliptic curve cryptography (ECC) processor architecture which performs all finite
field arithmetic operations in the discrete Fourier domain. The proposed architecture utilizes a class of optimal extension fields (OEF)
GF(q
m
) where the field characteristic is a Mersenne prime q = 2
n
− 1 and m = n. The main advantage of our architecture is that it achieves extension field modular multiplication in the discrete Fourier domain with only a linear number of base field GF(q) multiplications in addition to a quadratic number of simpler operations such as addition and bitwise rotation. We achieve
an area between 25k and 50k equivalent gates for the implementations over OEFs of size 169, 289 and 361 bits. With its low
area and high speed, the proposed architecture is well suited for ECC in small device environments such as sensor networks.
The work at hand presents the first hardware implementation of a frequency domain multiplier suitable for ECC and the first
hardware implementation of ECC in the frequency domain.
相似文献
Berk SunarEmail: |
976.
We present some results on the existence and multiplicity of solutions for boundary value problems involving equations of the type −Δu=f(x,u)+λg(x,u), where Δ is the Laplacian operator, λ is a real parameter and , are two Carathéodory functions having no growth conditions with respect to the second variable. The approach is variational and mainly based on a critical point theorem by B. Ricceri. 相似文献
977.
Large solutions of semilinear elliptic equations under the Keller-Osserman condition 总被引:1,自引:0,他引:1
Alan V. Lair 《Journal of Mathematical Analysis and Applications》2007,328(2):1247-1254
We consider the equation Δu=p(x)f(u) where p is a nonnegative nontrivial continuous function and f is continuous and nondecreasing on [0,∞), satisfies f(0)=0, f(s)>0 for s>0 and the Keller-Osserman condition where . We establish conditions on the function p that are necessary and sufficient for the existence of positive solutions, bounded and unbounded, of the given equation. 相似文献
978.
This paper reports the validation of the results obtained by combining near infrared spectroscopy and multivariate curve resolution-alternating least squares (MCR-ALS) and using high performance liquid chromatography as a reference method, for the model reaction of phenylglycidylether (PGE) and aniline. The results are obtained as concentration profiles over the reaction time. The trueness of the proposed method has been evaluated in terms of lack of bias. The joint test for the intercept and the slope showed that there were no significant differences between the profiles calculated spectroscopically and the ones obtained experimentally by means of the chromatographic reference method at an overall level of confidence of 5%. The uncertainty of the results was estimated by using information derived from the process of assessment of trueness. Such operational aspects as the cost and availability of instrumentation and the length and cost of the analysis were evaluated. The method proposed is a good way of monitoring the reactions of epoxy resins, and it adequately shows how the species concentration varies over time. 相似文献
979.
O. Martio V. M. Miklyukov M. Vuorinen 《Proceedings of the American Mathematical Society》2007,135(8):2433-2442
A variational inequality for the images of -dimensional hyperplanes under quasiconformal maps of the -dimensional Euclidean space is proved when
980.
Introduction Quantitative analysis in cyclic derivative chronopotentiometry(CDC) is based on the measurement of the depth of incision on the (dE/dt)~E curve. A serious disadvantage of the method is that a large charging current obscures the measurement. To improve the sensitivity and the accuracy of CDC, a microcomputer-based data acquisi- 相似文献