Dispersion for the Schr\"odinger Equation on Networks

In this paper we consider the Schr\"odinger equation on a network formed by a tree with the last generation of edges formed by infinite strips. We give an explicit description of the solution of the linear Schr\"odinger equation with constant coefficients. This allows us to prove dispersive estimates, which in turn are useful for solving the nonlinear Schr\"odinger equation. The proof extends also to the laminar case of positive step-function coefficients having a finite number of discontinuities.Comment: 16 pages, 2 figure

Measurables of CPCP Violation in Bd→DCP0KSB_d\to D^0_{CP}K_S at a BB-meson Factory

In the context of the standard electroweak model, we emphasize that $B_d\rightarrow D^0_{CP}K_S$ ($D^0_{CP}$ denotes a $CP$ eigenstate of $D^0$ or $\bar{D}^0$) can compete with $B_d\rightarrow \pi^+\pi^-$ in studying $CP$ violation and probing the Cabibbo-Kobayashi-Maskawa unitarity triangle. We discuss the measurables of direct and indirect $CP$ asymmetries in $B^0_d$ vs $\bar{B}^0_d\rightarrow D^0_{CP}K_S$ under the circumstance of an asymmetric $B$-meson factory running on the $\Upsilon(4S)$ resonance, and show that both the weak and strong phases are experimentally determinable even in the presence of unknown final-state interactions.Comment: 6 Postscript pages, accepted for publication in IL Nuovo Cimento A as a "Note Brevi

1/m_b^2 correction to the left-right lepton polarization asymmetry in the decay B -> X_s mu^+ mu^-

Using a known result by Falk et al. for the 1/m_b^2 correction to the dilepton invariant mass spectrum in the decay B \rightarrow X_s \mu^+ \mu^-, we calculate the 1/m_b^2 correction to the left-right muon polarization asymmetry in this decay. Employing an up-to-date range of values for the non-perturbative parameter \lambda_1, we find that the correction is much smaller than it should have been expected from the previous work by Falk et al.Comment: 8 pages, 2 figures included. Uses epsf.sty and rotate.sty. To appear in Physical Review D. The complete postscript file is also available from URL ftp://feynman.t30.physik.tu-muenchen.de/pub/preprints/ tum_t31_98_96.ps.g

Two Higgs Doublet Model and Lepton Polarization in the B -> K tau+ tau- Decay

The decay width, forward-backward asymmetry and tau lepton longitudinal and transversal polarization for the exclusive (B -> K tau^+ tau^-) decay in a two Higgs doublet model are computed. It is shown that the forward-backward asymmetry and longitudinal polarization of the tau lepton are very effective tools for establishing new physics.Comment: 25 pages, 20 figures, LaTeX formatte

Natural convection in polyethylene glycol based molybdenum disulfide nanofluid with thermal radiation, chemical reaction and ramped wall temperature

© 2018 International Information and Engineering Technology Association. All Rights Reserved. The aim of this study is to investigate the unsteady magnetohydrodynamic (MHD) flow of Casson nanofluid over an infinite oscillating vertical plate with ramped wall temperature. The effects of porosity, thermal radiation and first order chemical reaction have been considered. Polyethylene glycol (PEG) is chosen as base fluid which contained molybdenum disulfide (MoS 2 ) nanoparticles. The Laplace transform technique is applied to the momentum, energy and concentration equations to obtain the closed form solutions. The obtained solutions are for both cases ramped and isothermal boundary conditions and compared graphically. From graphical analysis, it is observed that for isothermal plate, the magnitude of velocity, temperature and concentration profiles are greater than ramped wall temperature. Skin-friction, Nusselt number and Sherwood number are evaluated and presented in tabular forms. The effects of various embedded parameters on velocity, temperature and concentration profiles are discussed graphically

Dynamic Wireless Information and Power Transfer Scheme for Nano-Empowered Vehicular Networks

In this paper, we investigate the wireless power transfer and energy-efficiency (EE) optimization problem for nano-centric vehicular networks operating over the terahertz band. The inbody nano-sensors harvest energy from a power station via radio-frequency signal and then use the harvested energy to transmit data to the sink node. By considering the properties of terahertz band (i.e., sensitivity to distance and frequency over the communication path), we adopt the Brownian motion model to develop a time-variant terahertz channel model and to describe the mobility of the nano-sensors. Thus, based on the channel model and energy resources, we further develop a long-term EE optimization problem. The EE optimization is further converted into a series of energy-efficient resource allocation problems over the time slots via equivalent transformation method. The resource allocation problem for each timeslot, which is formulated as a mixed integer nonlinear programming (MINLP), is solved based on the particle swarm optimization (PSO) method. In addition, a dynamic PSO-based EE optimization (DPEEO) algorithm is developed to obtain the sub-optimal solution for the EE optimization problem. By exploiting the special structure of the reformulated problem, an improved DPEEO algorithm, is presented which can handle the problem’s constraints quite well, decreases the research space, and greatly reduces the length of the convergence time. Simulation results validate the theoretical analysis of our system