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991.
《Discrete Mathematics》2019,342(7):1924-1948
Multiple-weight optical orthogonal signature pattern codes (OOSPCs) were introduced by Kwong and Yang for 2-D image transmission in multicore-fiber optical code-division multiple-access (OCDMA) networks with multiple quality of services (QoS) requirement. In this paper, an upper bound on the maximum code size of a -OOSPC is obtained. A link between optimal -OOSPCs and block designs is developed. Several infinite families of optimal -OOSPCs are presented by means of semi-cyclic group divisible designs (-SCGDDs) and perfect relative difference families. 相似文献
992.
The characteristic energy band values such as the Fermi-level position with respect to valence band top for a boron-doped p-type hydrogen-terminated chemical-vapor-deposition (CVD) diamond (0 0 1)2 × 1 surface and for a clean CVD diamond (0 0 1)2 × 1 surface have been determined by a new method with an accuracy of ±0.02 eV. The electron attenuation length for the clean diamond (0 0 1)2 × 1 surface for the electron kinetic energy of C 1s X-ray photoemission peak by Mg Kα excitation is experimentally determined to be 2.1-2.2 nm. These values are compared and discussed with the previously reported experimental and simulation values. 相似文献
993.
By using the invariant set of descending flow and variational method, we establish the existence of multiple solutions to a class of second-order discrete Neumann boundary value problems. The solutions include sign-changing solutions, positive solutions, and negative solutions. An example is given to illustrate our results. 相似文献
994.
Ying Sue Huang 《Journal of Difference Equations and Applications》2020,26(7):871-912
ABSTRACT We study a large class of finite difference equations that exhibit a type of periodic pattern repetition in their solutions for certain choices of initial conditions and prove the existence of unbounded solutions. 相似文献
995.
996.
997.
Using a slight modification of an argument of Croot, Ruzsa and Schoen we establish a quantitative result on the existence of a dilated copy of any given configuration of integer points in sparse difference sets. More precisely, given any configuration {v1,…,v?} of vectors in Zd, we show that if A⊂d[1,N] with |A|/Nd?CN−1/?, then there necessarily exists r≠0 such that {rv1,…,rv?}⊆A−A. 相似文献
998.
E. Sava? 《Applied mathematics and computation》2010,217(1):271-276
In this paper, we study certain new difference sequence spaces using ideal convergence and an Orlicz function in 2-normed spaces and we give some relations related to these sequence spaces. 相似文献
999.
Analyzing a large number of unfixed gels in a 2-D fluorescence difference gel electrophoresis (2-DIGE) experiment presents a challenge of avoiding variable protein diffusion within and across the comparison groups. The characteristics of protein detection and quantitation in a 2-D differential in gel fluorescence experiment were compared for gels with and without protein fixation. The current study tests and concludes that when dealing with a large sample size with variable protein diffusion across the 2-D gel over a period of 2-4 days, it is a preferred choice to fix the gel without affecting the protein quantitation. 相似文献
1000.
Amparo Gil Javier Segura Nico M. Temme 《Journal of Computational and Applied Mathematics》2006,190(1-2):270-286
Each member of the family of Gauss hypergeometric functions
fn=2F1(a+ε1n,b+ε2n;c+ε3n;z),