In this paper, two kinds of vibrations are considered for a composite Timoshenko rotor: longitudinal-torsional vibration and two plane transverse one. The kinetic and potential energies and virtual work due to the gyroscopic effects are calculated and the set of six governing equations and boundary conditions are derived using Hamilton principle. Differential quadrature method (DQM) is used as ...

In this paper, we have investigated the effects of asymmetry in the source and drain capacitance of metallic island single electron transistors. By comparing the source and drain Fermi levels, in the ground and source referenced biasing configurations, with the island’s discrete charging energy levels for various gate voltages, we have derived a set of closed form equations for the device thres...

‎let $x$ be a real normed  space, then  $c(subseteq x)$  is  functionally  convex  (briefly, $f$-convex), if  $t(c)subseteq bbb r $ is  convex for all bounded linear transformations $tin b(x,r)$; and $k(subseteq x)$  is  functionally   closed (briefly, $f$-closed), if  $t(k)subseteq bbb r $ is  closed  for all bounded linear transformations $tin b(x,r)$. we improve the    krein-milman theorem  ...

in this article, we have shown, for the add-point monad t, thepartial morphism category set*is isomorphic to the kleisli category sett. alsowe have proved that the category, sett, of t-algebras is isomorphic to thecategory set of pointed sets. finally we have established commutative squaresinvolving these categories.

the linear adiabatic pulsation-periods of mira variable stars have been derived. approximately 2701[1]models were calculated for m = 0.7 mθ to 2 mθ stars with radii from 180 rθ to 340 rθ and luminosities from 2800 lθ to 10,000 lθ. the chemical composition of all models is (x,z) = (0.7,0.02). from the result of this study, linear relations on luminosity-period-mass relationship and luminosity-pe...

Normal residual is one of the usual assumptions of autoregressive models but in practice sometimes we are faced with non-negative residuals case. In this paper we consider some autoregressive models with non-negative residuals as competing models and we have derived the maximum likelihood estimators of parameters based on the modified approach and EM algorithm for the competing models. Also,...

Data Envelopment Analysis (DEA) as a non-parametric method for efficiency measurement allows decision making units (DMUs) to select the most advantageous weight factors in order to maximize their efficiency scores.  In most practical applications of DEA presented in the literature, the presented models assume that all inputs are fully desirable. However, in many real situations undesirable inpu...

Tumor- or cancer-associated fibroblasts (TAFs or CAFs) from different tumors exhibit distinct angiogenic and tumorigenic properties. Unlike normal skin fibroblasts or TAFs from TIB6 tumors that are sensitive to anti-VEGF treatment (TAF-TIB6), TAFs from resistant EL4 tumors (TAF-EL4) can stimulate TIB6 tumor growth even when VEGF is inhibited. We show that platelet-derived growth factor C (PDGF-...