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861.
862.
Daniel J. Katz 《Designs, Codes and Cryptography》2012,65(3):291-324
We present a theorem that generalizes the result of Delsarte and McEliece on the p-divisibilities of weights in abelian codes. Our result generalizes the Delsarte–McEliece theorem in the same sense that the theorem of N. M. Katz generalizes the theorem of Ax on the p-divisibilities of cardinalities of affine algebraic sets over finite fields. As the Delsarte–McEliece theorem implies the theorem of Ax, so our generalization implies that of N. M. Katz. The generalized theorem gives the p-divisibility of the t-wise Hamming weights of t-tuples of codewords (c (1), . . . ,c (t)) as these words range over a product of abelian codes, where the t-wise Hamming weight is defined as the number of positions i in which the codewords do not simultaneously vanish, i.e., for which ${(c^{(1)}_i,\ldots,c^{(t)}_i)\not=(0,\ldots,0)}$ . We also present a version of the theorem that, for any list of t symbols s 1, . . . ,s t , gives p-adic estimates of the number of positions i such that ${(c^{(1)}_i,\ldots,c^{(t)}_i)=(s_1,\ldots,s_t)}$ as these words range over a product of abelian codes. 相似文献
863.
Ricardo D. Katz Hans Schneider Sergeı˘ Sergeev 《Linear algebra and its applications》2012,436(2):276-292
This paper studies commuting matrices in max algebra and nonnegative linear algebra. Our starting point is the existence of a common eigenvector which directly leads to max analogs and nonnegative analogs of some classical results for complex matrices. We also investigate Frobenius normal forms of commuting matrices, particularly when the Perron roots of the components are distinct. For the case of max algebra, we show how the intersection of eigencones of commuting matrices can be described and we consider connections with Boolean algebra which enables us to prove that two commuting irreducible matrices in max algebra have a common eigennode. 相似文献
864.
Jinfeng Han Yufeng Jiang Emma Tiernan Connor Ganley Yunjia Song Taein Lee Arlene Chiu Patty McGuiggan Nicholas Adams Paulette Clancy Thomas P Russell Patrick E. Hopkins Susanna M. Thon John D. Tovar Howard E. Katz 《Angewandte Chemie (International ed. in English)》2023,62(23):e202219313
N-Type thermoelectrics typically consist of small molecule dopant+polymer host. Only a few polymer dopant+polymer host systems have been reported, and these have lower thermoelectric parameters. N-type polymers with high crystallinity and order are generally used for high-conductivity ( ) organic conductors. Few n-type polymers with only short-range lamellar stacking for high-conductivity materials have been reported. Here, we describe an n-type short-range lamellar-stacked all-polymer thermoelectric system with highest of 78 S−1, power factor (PF) of 163 μW m−1 K−2, and maximum Figure of merit (ZT) of 0.53 at room temperature with a dopant/host ratio of 75 wt%. The minor effect of polymer dopant on the molecular arrangement of conjugated polymer PDPIN at high ratios, high doping capability, high Seebeck coefficient (S) absolute values relative to , and atypical decreased thermal conductivity ( ) with increased doping ratio contribute to the promising performance. 相似文献
865.
Aluminum - epoxy single lap joints were subjected at different temperatures to torsional vibrations at constant amplitude superimposed on a creep load. This combination of dynamic and static stresses was chosen in order to simulate to a certain extent the real service conditions of an ordinary bonded joint. The shear strength of these joints was checked in tension at room temperature after their removal from the special device in which the superimposed stresses were applied. It was found that the shear strength of the joint is very dependent on its thermo-mechanical history. DSC analyses and SEM micrographs of the failure surface were used in an attempt to find some correlation between the mechanical properties and the microstructure of the adhesive. 相似文献
866.