A general framework for the regularization of constrained PDEs, also called operator DAEs, is presented. The given procedure works for semi-explicit operator DAEs of first order which includes the Navier-Stokes and other flow equations. This reformulation is a regularization in the sense that a semi-discretization in space leads to a DAE of lower index, i.e., of differentiation index 1 instead ...

– The Wigner equation taking into account both the non-local potential operator and a scattering operator represents a suitable physical model for carrier transport in nano structures. In this paper a new Monte Carlo method is proposed for the solution of the stationary Wigner equation. Scattering can be included at the level of the semi-classical Boltzmann scattering operator, whereas coherent...

We show that the non-linear semi-quantum Hamiltonians which may be expressed as ( ) ( ) ˆ ˆ ∑ N j j j p H a q p O V q m 2 1 , 2 = = + + (where ˆ j O is the set of generators of some Lie algebra and ( ) q p , are the classical conjugated canonical variables) always close a partial semi Lie algebra under commutation and, because of this, it is always possible to integrate the mean values of the q...

We study orthogonal polynomials and Hankel determinants generated by a symmetric semi-classical Jacobi weight. By using the ladder operator technique, we derive second-order nonlinear difference equations satisfied recurrence coefficient $\beta_n(t)$ sub-leading $\mathrm{p}(n,t)$ of monic polynomials. This enables us to obtain large $n$ asymptotics based on result Kuijlaars et al. [Adv. Math. \...

This paper is concerned with the influence of frequency modulation on the semiFredholm properties of Toeplitz operators with oscillating matrix symbols. The main results give conditions on an orientation-preserving homeomorphism α of the real line that ensure the following: if b belongs to a certain class of oscillating matrix functions (periodic, almost periodic, or semi-almost periodic matrix...

A Banach space operator T satisfies property(Bgw), a variant property(gw), if the complement in the approximate point spectrum σa(T ) of the semi-B-essential approximate point spectrum σSBF− + (T ) coincides with set of isolated eigenvalues of T of finite multiplicity E(T ). We also introduce properties (Bb), and property (Bgb) in connection with Weyl type theorems, which are analogous, respect...

Let A be a positive (semidefinite) bounded linear operator on complex Hilbert space $$\big ({\mathcal {H}}, \langle \cdot , \rangle \big )$$ ( H ? · ? ) . The semi-inner product induced by is defined $${\langle x, y\rangle }_A := Ax, $$ x y : = for all $$x, y\in {\mathcal {H}}$$ ? and defines seminorm $${\Vert \Vert }_A$$ ? $${\mathcal This makes into semi-Hilbert space. For $$p\in [1,+\infty p...

0. Introduction. Let us begin by recalling brieey some salient facts from classical Hankel theory (cf. Ni]). Consider the Hardy class H 2 (T), where T is the unit circle in C , and let H 2 (T) ? be its orthogonal complement in the space L 2 (T). If is a holomorphic function, one deenes the Hankel operator H with symbol by the formula H f = P ? f (f 2 H 2 (T)) where P ? stands for orthogonal pro...

for a bounded linear operator on hilbert space we define a sequence of the so-called weakly extremal vectors‎. ‎we study the properties of weakly extremal vectors and show that the orthogonality equation is valid for weakly extremal vectors‎. ‎also we show that any quasinilpotent operator $t$ has an hypernoncyclic vector‎, ‎and so $t$ has a nontrivial hyperinvariant subspace‎.

Parallel Prefix addition is a technique for improving the speed of binary addition. Due to continuing integrating intensity and the growing needs of portable devices, low-power and highperformance designs are of prime importance. The classical parallel prefix adder structures presented in the literature over the years optimize for logic depth, area, fan-out and interconnect count of logic circu...