in this study, friction stir spot welding (fssw) is applied to join the tial6v4 titanium alloy with 1.5 mm thickness and then the effect of rotational speed and tool dwell time on microstructure and mechanical properties is investigated. in this regard, the speed of the tool rotation was considered as 800, 1000, and 1200 rpm, as well as the tool dwell time was set at 7 and 12s. microstructural ...

Let $ m , n in mathbb{N}$, $D$ be a division ring, and $M_{m times n}(D)$ denote the bimodule of all $m times n$ matrices with entries from $D$. First, we characterize one-sided submodules of $M_{m times n}(D)$ in terms of left row reduced echelon or right column reduced echelon matrices with entries from $D$. Next, we introduce the notion of a nest module of matrices with entries from $D$. We ...

SM3 is a hash function, designed by Xiaoyun Wang et al. and published by the Chinese Commercial Cryptography Administration Office for the use of electronic authentication service system. The design of SM3 builds upon the design of the SHA-2 hash function, but introduces additional strengthening features. In this paper, we present boomerang distinguishers for the SM3 compression function reduce...

Within the framework of probability representation quantum mechanics, we study a superposition generic Gaussian states associated to symmetries regular polygon n sides; in other words, cyclic groups (containing rotational symmetries) and dihedral inversion symmetries). We obtain Wigner functions tomographic distributions (symplectic optical tomograms) determining density matrices explicitly as ...

A six-node co-rotational curved triangular shell finite element with a novel rotation treatment for folded and multi-shell structures is presented. Different from other formulations, rotations are not represented by axial (pseudo) vectors, but components of polar (proper) which additivity commutativity lead to symmetry the tangent stiffness matrices in both local global coordinate systems. In s...

Some aspects of the perturbation theory for eigenvalues of unitary matrices are considered. Making use of the close relation between unitary and Hermitian eigenvalue problems a Courant-Fischer-type theorem for unitary matrices is derived and an inclusion theorem analogue to the Kahan theorem for Hermitian matrices is presented. Implications for the special case of unitary Hessenberg matrices ar...

The rotational structure in the vibrational transitions from v50 to v51, 2, 3, 4 of HCl and HCl is studied in Xe, Kr, and Ar matrices with high spectral resolution. A consistent set of rotational constants Bv for the vibrational levels v50 to 4 is derived. B0 decreases with the tightness of the cage from 9.78 cm in Xe to 8.83 cm in Ar for HCl ~gas phase 10.44 cm!. The values for B0 to B4 decrea...

We studied 32 patients who had complex lesions or morphologic characteristics associated with poor outcome utilizing conventional PTCA, such as ostial stenosis, calcified lesions, long or diffuse lesions, restenotic lesions or Lesions which can not be crossed or dilnted with a balloon. These 32 patients underwent 72 procedures in which rotational atherectomy and adjuncrive or complementary PTCA...

BACKGROUND To evaluate the rotational stability of the three types of AcrySof SA60TT toric intraocular lenses (Alcon, Switzerland) in cataract surgery after the first postoperative week. METHODS A retrospective study of 44 eyes in 33 patients. All patients underwent similar uncomplicated phacoemulsification cataract surgery. Seven eyes with corneal astigmatism of less than 1.5 D were implante...

root morphological and distribution responses of signal grass (brachiaria decumbens) to long-term cattle grazing were examined in a tropical pasture in malaysia. the treatments were no grazing by cattle and grazing at a moderate stocking density (2.7 animal unit/ha) under rotational grazing for 33 years. the method consists of taking soil core using a soil corer to a depth of 30 cm and extracti...