7,092 research outputs found
A Time Dependent Multi-Determinant approach to nuclear dynamics
We study a multi-determinant approach to the time evolution of the nuclear
wave functions (TDMD). We employ the Dirac variational principle and use as
anzatz for the nuclear wave-function a linear combination of Slater
determinants and derive the equations of motion. We demonstrate explicitly that
the norm of the wave function and the energy are conserved during the time
evolution. This approach is a direct generalization of the time dependent
Hartree-Fock method. We apply this approach to a case study of using
the N3LO interaction renormalized to 4 major harmonic oscillator shells. We
solve the TDMD equations of motion using Krylov subspace methods of Lanczos
type. We discuss as an application the isoscalar monopole strength function.Comment: 38 pages, additional calculations included. Accepted for publication,
Int. J. of Mod. Phys.
Doing Science: How to optimise patient and public involvement in your research
This paper considers how best to achieve patient and public involvement in research and how to get the most out of it http://ow.ly/R0hwV
Doing Science: How to optimise patient and public involvement in your research
This paper considers how best to achieve patient and public involvement in research and how to get the most out of it http://ow.ly/R0hw
Sum-Rate Analysis for High Altitude Platform (HAP) Drones with Tethered Balloon Relay
High altitude platform (HAP) drones can provide broadband wireless
connectivity to ground users in rural areas by establishing line-of-sight (LoS)
links and exploiting effective beamforming techniques. However, at high
altitudes, acquiring the channel state information (CSI) for HAPs, which is a
key component to perform beamforming, is challenging. In this paper, by
exploiting an interference alignment (IA) technique, a novel method for
achieving the maximum sum-rate in HAP-based communications without CSI is
proposed. In particular, to realize IA, a multiple-antenna tethered balloon is
used as a relay between multiple HAP drones and ground stations (GSs). Here, a
multiple-input multiple-output X network system is considered. The capacity of
the considered M*N X network with a tethered balloon relay is derived in
closed-form. Simulation results corroborate the theoretical findings and show
that the proposed approach yields the maximum sum-rate in multiple HAPs-GSs
communications in absence of CSI. The results also show the existence of an
optimal balloon's altitude for which the sum-rate is maximized.Comment: Accepted in IEEE Communications Letter
Sums and Partial Sums of Double Power Series associated with the Generalized Zeta Function and Their N-fractional CalculusSums and Partial Sums of Double Power Series associated with the Generalized Zeta Function and Their N-fractional Calculus
An attempt is made here to introduce and study a pair of
double power series associated with the generalized zeta function due to Erdélyi Φ(x; z; a) together with related sums, integral representations,
generating relations and N-fractional calculus. A number of (known and
new) results shown to follow as special cases of our theorems.</p
Solutions for certain classes of Riccati differential equation
We derive some analytic closed-form solutions for a class of Riccati equation
y'(x)-\lambda_0(x)y(x)\pm y^2(x)=\pm s_0(x), where \lambda_0(x), s_0(x) are
C^{\infty}-functions. We show that if \delta_n=\lambda_n
s_{n-1}-\lambda_{n-1}s_n=0, where \lambda_{n}=
\lambda_{n-1}^\prime+s_{n-1}+\lambda_0\lambda_{n-1} and
s_{n}=s_{n-1}^\prime+s_0\lambda_{k-1}, n=1,2,..., then The Riccati equation has
a solution given by y(x)=\mp s_{n-1}(x)/\lambda_{n-1}(x). Extension to the
generalized Riccati equation y'(x)+P(x)y(x)+Q(x)y^2(x)=R(x) is also
investigated.Comment: 10 page
- …