Wilkinson Power Dividers/Combiners The in-phase power combiners and dividers are important components of the RF and microwave transmitters when it is necessary to deliver a high level of the output power to antenna, especially in phased-array systems. In this case, it is also required to provide a high degree of isolation between output ports over some frequency range for identical in-phase sig...

Di-chloro-bis[chloro(triphenylphosphine)mercury(II)], [Hg2Cl4(C18H15P)2], (I), and di-bromo-bis[bromo(triphenylphosphine)mercury(II)], [Hg2Br4(C18H15P)2], (II), have been reinvestigated at 120 K. The molecules of (I) lie across inversion centres in space group P21/n, and in both (I) and (II) the complexes are linked into three-dimensional frameworks by a combination of CÐH X (X = Cl and Br) and...

where Z, U are Hilbert spaces, A : D(A) ⊂ Z −→ Z is the infinitesimal generator of strongly continuous semigroup {T (t)}t≥0 inZ, B ∈ L(U,Z), the control function u belongs to L(0, τ ;U) and F : [0, τ ]× Z × U −→ Z is a suitable function. First, we give a necessary and sufficient condition for the exact controllability of the linear system z′ = Az + Bu(t); Second, under some conditions on F , we...

The existence and uniqueness of vortex solutions is proved for Ginzburg– Landau equations with external potentials in R2. These equations describe the equilibrium states of superconductors and the stationary states of the U(1)-Higgs model of particle physics. In the former case, the external potentials are due to impurities and defects. Without the external potentials, the equations are transla...

We have searched for prompt heavy quarkonia and Bc mesons in 3 × 106 hadronic Z0 decays recorded with the DELPHI detector at LEP. No signal was observed in any of these modes. We achieved the highest sensitivities for gluon fragmentation into J/ψ and for semileptonic B c decays, yielding branching ratio upper limits of B(Z 0 → J/ψggX) < 4.1×10−4 and B(Z0 → B c X)·B(B ± c → J/ψl νl) < 5.0×10 −5 ...

In the early 1980’s an elementary algorithm for computing conformal maps was discovered by R. Kühnau and the first author. The algorithm is fast and accurate, but convergence was not known. Given points z0, . . . , zn in the plane, the algorithm computes an explicit conformal map of the unit disk onto a region bounded by a Jordan curve γ with z0, . . . , zn ∈ γ. We prove convergence for Jordan ...