We calculate near zero recoil the order αs corrections to the Bjorken and Voloshin sum rules that bound the B → D(∗) l ν̄ form factors. These bounds are derived by relating the result of inserting a complete set of physical states in a time ordered product of weak currents to the operator product expansion. The sum rules sum over physical states with excitation energies less than a scale ∆. We f...

This paper presents an algorithm for implementing a k-ary regular register (the logical register) using k(k -1 )/2 binary regular registers (the physical registers) that requires only one physical write per logical write. The algorithm is simple to describe and depends on properties of paths in a related graph. Two lower bounds on the number of registers required by one-write implementations ar...

In this paper‎, ‎using the discrete Fourier transform in the finite-dimensional Hilbert space C^n‎, ‎a class of nonRieszable equal norm tight frames is introduced ‎and‎ using this class, a bound for Fiechtinger Conjecture is presented. By the Fiechtinger Conjecture that has been proved recently, for given A,C>0 there exists a universal constant delta>0 independent of $n$ such that every C-equal...

in the present paper, the deformation zone of the ecae (equal channel angular extrusion) process was investigated using the upper bound theorem. for this purpose, the shape of the streamlines in the deformation zone was assumed to be cubic bezier curves. then, the force required for the ecae process was optimized with regard to the parameters defining the shape of streamlines by the upper bound...

this paper presents a new nonlinear mathematical model to solve a cell formation problem which assumes that processing time and inter-arrival time of parts are random variables. in this research, cells are defined as a queue system which will be optimized via queuing theory. in this queue system, each machine is assumed as a server and each part as a customer. the grouping of machines and parts...

precision forging process is widely used for the production of spur gears due to its advantages such asimproved strength and surface finish, little waste of materials and reduction in the machining time ofthe gear. an important aspect of precision forging process is the load required to perform the processsuccessfully and design the forging tools. in this research, a new kinematically admissibl...