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21.
近年来,伽罗瓦环上的序列理论成为人们研究的热点问题.有限域上的No序列是一类伪随机序列,它在序列密码中占具十分重要的角色.本文利用伽罗瓦环上的置换,构造了伽罗瓦环Z_(p~e)上的一类新的No序列,并且研究了其线性复杂度.研究的结果表明此类No序列具有相当大的线性复杂度. 相似文献
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Finite commutative semi-simple rings are direct sum of finite fields. In this study, we investigate the algebraic structure of λ-constacyclic codes over such finite semi-simple rings. Among others, necessary and sufficient conditions for the existence of self-dual, LCD, and Hermitian dual-containing λ-constacyclic codes over finite semi-simple rings are provided. Using the CSS and Hermitian constructions, quantum MDS codes over finite semi-simple rings are constructed. 相似文献
24.
The main results of this paper are in two directions. First, the family of finite local Frobenius non-chain rings of length 4 (hence of nilpotency index 3) is determined. As a by-product all finite local Frobenius non-chain rings with elements, (p a prime) are given. Second, the number and structure of γ-constacyclic codes over finite local Frobenius non-chain rings with nilpotency index 3, of length relatively prime to the characteristic of the residue field of the ring, are determined. 相似文献
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Application of X-ray diffraction, micromagnetic and hole drilling methods for residual stress determination in a ball bearing steel ring 总被引:1,自引:0,他引:1
C. O. D. Martins Ph.D. T. R. Strohaecker A. S. Rocha T. K. Hirsch 《Experimental Mechanics》2005,45(4):344-350
A basic understanding of distortion problems requires the analysis of a complete manufacturing process including an almost
complete overview of residual stress states in the component during each production step. To reduce the measurement time in
the future, three measurements methods (X-ray diffraction, micromagnetic and blind hole drilling methods) have been used to
analyze residual stress states in machined AISI 52100 ball bearing rings. X-ray diffraction was used as a state-of-the-art
method for machining induced residual stresses with pronounced gradients. The ring exhibited a complex residual stress state
with high tensile residual stresses at the surface, a strong gradient in depth, and also showed some variation along the outer
circumference due to a superimposition of machining induced residual stresses and effects from the clamping device process.
Due to this surface state, micromagnetic signals depend on the analyzing frequency. A calibration of the signals was only
possible with the X-ray diffraction data. The results of the three different measurement methods correlate reasonably well. 相似文献
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C.A. Castillo-Guillén C. Rentería-Márquez E. Sarmiento-Rosales H. Tapia-Recillas R.H. Villarreal 《Discrete Mathematics》2019,342(8):2283-2296
Over finite local Frobenius non-chain rings with nilpotency index 3 and when the length of the codes is relatively prime to the characteristic of the residue field of the ring, the structure of the dual of -constacyclic codes is established and the algebraic characterization of self-dual -constacyclic codes, reversible -constacyclic codes and -constacyclic codes with complementary dual are given. Generators for the dual code are obtained from those of the original constacyclic code. 相似文献
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