A randomised approximation scheme for the permanent of a 0-1 matrix is presented. The task of estimating a permanent is reduced to that of almost uniformly generating perfect matchings in a graph; the latter is accomplished by simulating a Markov chain whose states are the matchings in the graph. For a wide class of 0-1 matrices the approximation scheme is fully-polynomial, i.e., runs in time p...

Transient silencing made permanent A ll cancers have genes that are permanently silenced by DNA methylation. Yeshayahu Schlesinger, Howard Cedar (The Hebrew University, Israel), and colleagues, and Martin Widschwendter (UCL, London, UK), Peter Laird (USC, Los Angeles, CA), and colleagues inspect these irreversibly silenced genes. In normal tissues, they fi nd, these genes carry transient repres...

The conventional method to evaluate earthquake induced permanent deformations of slopes is the one proposed by Newmark. In this paper, permanent displacement of slopes is studied using a combination of distinct element and finite difference methods and the results of these numerical evaluations are compared with those of the Newmark's approach. Several parameters involved, including peak ground...

In this paper, a new type of harmonic injection permanent magnet shape optimization method is proposed to suppress the torque ripple surface-mounted synchronous motor. The sinusoidal waveform shaping axial section added with third shaping, and sine wave are derived. optimal ratio 6:1. no combined compared. results show that design can effectively surface mounted motor obtain relatively large ou...

For line start permanent magnet synchronous machines (LSPMSMs), the eddy current loss in the rotor, which has of significant effects on rotor working temperature, may cause thermal demagnetization to permanent magnet. Therefore, this paper addresses an investigation on the temperature distribution in LSPMSM based on a 6 kV, 315 kW prototype with solid starting cage bar. Firstly, the loss distri...