Disk brake squeal noise is mainly due to unstable friction-induced vibration. A typical disk brake system includes two pads, a rotor, a caliper and a piston. In order to predict if a disk brake system will generate squeal, the finite element method (FEM) is used to simulate the system. At the contact interfaces between the pads and the rotor, the normal displacement is continuous and Coulomb’s ...

We present a novel recursive algorithm for reducing a symmetric matrix to a triangular factorization which reveals the rank profile matrix. That is, the algorithm computes a factorization PAP = LDL where P is a permutation matrix, L is lower triangular with a unit diagonal and D is symmetric block diagonal with 1×1 and 2×2 antidiagonal blocks. The novel algorithm requires O(n2rω−2) arithmetic o...

The rise in the demand towards unsymmetric porphyrin systems for use in applications such as photodynamic therapy and non-linear optics mandates a concomitant development of simple and practical syntheses thereof. A new methodology for the rapid generation of unsymmetrical porphyrins synthesized from the same common and easily accessible symmetric porphyrin starting material is discussed herein...

The objective of the paper is to demonstrate the calculation of micromorphic continuum stress measures based directly on three-dimensional (3D) ellipsoidal discrete element (DE) simulations over representative volume elements (RVE) within the DE domain representing granular media. We will demonstrate these calculations for two simulations: (1) pile penetration, and (2) cavity expansion. All cal...

For the eigenvalues of a large and sparse unsymmetric co-eecient matrix, we have proposed an improved version of the unsymmetric Lanczos process combining elements of numerical stability and parallel algorithm design. The algorithm is derived such that all inner products and matrix-vector multiplications of a single iteration step are independent and communication time required for inner produc...

A family of anionic, formally nickel(0) complexes supported by bidentate NHC–pyridone ligands is described. The unsymmetric chelating environment and capping [K(18-crown-6)]+ countercation allow isolation single-component, monometallic in high yield. steric electronic properties are assessed through a battery experimental (NMR, IR, UV–vis, X-ray diffraction) computational tools. Catalytic activ...