ARIMA: Bevölkerungsprognosen für Deutschland und Rheinland-Pfalz

Die Analyse präsentiert Prognosen für die deutsche und rheinland-pfälzische Bevölkerung mithilfe von ARIMA-Modellen. Außerdem wird ein Vergleich dieser Ergebnisse zu den theoriehaltigen Prognosen des Statistischen Bundesamtes, des Statistischen Landesamtes Rheinland-Pfalz und des Bundesamtes für Bauwesen und Raumordnung gezogen. Die Prognose befasst sich mit der Veränderung des Bevölkerungsstandes und der Altersstruktur bis zum Jahr 2020. ; The aim of this paper is, on one hand, to develop forecasts for the populations of the state Rhineland-Palatinate and Germany by ARIMA models. The other goal is a comparison of the ARIMA computations with the theory-based forecasts of the German Federal Statistical Offices and the Federal Office for Building and Regional Planning. The analysis deals with the change of the population numbers and the age structure. The year 2020 is our horizon of forecast. --

Splitness of the Veronesean dual hyperovals: a quick proof

Satoshi Yoshiara shows in [7] that the Veronesean dual hyperovals over ({mathbb F}_2) are of split type. So far there exists no published proof that a Veronesean dual hyperoval over any finite field of even characteristic is of split type. In this note we give a quick proof of this fact

Development and Implementation of High-Level Propagator Methods for the Description of Electronically Stable and Unstable States

Interactions of atoms or molecules with electromagnetic radiation or free electrons can induce a variety of transformations. Apart from elastic scattering processes, in which the quantum states of the involved particles are preserved, inelastic scattering may occur. The distribution of product states depends on the kind of the interacting particles and the energy transferred in the scattering process. Among the possible transformations are electronic excitation, photoionization and the formation of electronic resonances, i.e., metastable electronic states which undergo subse quent decay by emission of an electron. The latter states can evolve in electronic excitation processes or as a result of electron attachment. In this dissertation, the implementation and application of quantum chemical propagator methods for the description of the above-mentioned processes are presented. More specifically, a number of perturbation theoretical methods based on the algebraic diagrammatic construction (ADC) schemes for the electron propagator and the polarization propagator are considered. In the framework of these methods, one-electron properties are available via the intermediate state representation (ISR) approach, which enables the computation of the explicit form of the respective wave functions. The third-order static self-energy Σ(3) appearing in the third-order ADC(3) equations can thereby be replaced by an improved fourth-order quantity resulting from the so-called Σ(4+)-procedure, and this option has been explored in the context of ADC for ionization potentials (IP-ADC), electron affinities (EA-ADC) and, for the first time, excitation energies (PP-ADC). In the first part of this dissertation, photoionization processes are considered, whose theoretical treatment is possible using IP-ADC(3). In the course of this work, the existing implementation of IP-ADC(3) in the Q-Chem quantum chemical program package has been extended by the possibility to compute photoelectron intensities, and therefore, to simulate photoelectron spectra. Other newly implemented features enable the interpretation of ionization transitions by means of visualization of Dyson orbitals and one-particle density matrix-based quantities as, e.g., detachment and attachment densities, which are available via the second-order ISR(2) approach. The accuracy of the IP-ADC(3)/ISR(2) methodology with respect to ionization potentials and one-particle properties of electron-detached states has been evaluated in a subsequent benchmark study. Therein, the results obtained for 44 electronic states of small molecules are compared to high-level configuration interaction results. For this set of transitions, ionization potentials exhibit a mean absolute error of |∆| ≈ 0.2 eV. For dipole moments, a relative error of |∆| = 19 % is found. In a second IP-ADC(3) study, the applicability of the newly implemented density matrix-based analyses for the interpretation of photoelectron spectra is demonstrated using the example of the galvinoxyl free radical. In the second part of this dissertation, electronic resonances are addressed. Due to the unbound nature of the involved electronic states, their theoretical treatment is challenging. Different theoretical approaches for their description within the framework of standard quantum chemical methods have been devised, two of which are considered in this work. First, the efficient implementation of the Fano-Stieltjes-ADC method in the Q-Chem program is presented. For the first time, the third-order PP-ADC(3) scheme as well as various unrestricted PP-ADC schemes have been combined with the Fano-Stieltjes formalism. The applicability of the implementation for the description of resonances in medium-sized organic molecules is demonstrated in a study of a Feshbach resonance in the naphthalene molecule. As a second option for the theoretical treatment of electronic resonances, the combination of the subspace-projected complex absorbing potential (CAP) method with PP- ADC(3) and EA-ADC(3) is considered. Results obtained using the novel CAP-EA-ADC and CAP-PP-ADC methods as implemented in the Q-Chem quantum chemical program package show an excellent agreement with theoretical best estimates and experimental data in studies of π* shape resonances in unsaturated molecules. Among the studied resonance states are the ²Πg resonance of the dinitrogen anion as well as the lowest π* resonances of the anions of the non-conjugated organic dienes norbornadiene and 1,4-cyclohexadiene. CAP-EA-ADC(3) calculations are in line with previous findings and show that a strong through-bond interaction mechanism reverses the natural ordering of the π* molecular orbitals in 1,4-cyclohexadiene

Experimental and numerical investigation of a moored floating structure in waves

Floating structures play a major role in a wide range of traditional industrial branches as well as in recently developing sectors such as renewable energies. An accurate prediction of the movement of floating structures induced by varying environmental loads is essential for their design. Numerical models nowadays play a key role in the calculation of processes in hydraulic and marine engineering, due to their advantage in cost and time efficiency. Nonetheless, the traditional approach of physical model experiments has not lost its importance since the validity of numerical tools has to be ensured. REEF3D is an open-source numerical CFD solver developed at the Department of Civil and Environmental Engineering at the NTNU. It solves the Reynolds averaged Navier-Stokes equations in two phases using a finite differences method and a level set method to capture the free surface between water and air. Floating structures are represented as a level set function, too. The motion of the function is based on the rigid body dynamics in 6DOF. A directional immersed boundary method is used to implicitly incorporate appropriate boundary conditions at the fluid-structure interface. A set of benchmark data is to be generated at the physical wave flume of the Ludwig-Franzius institute in Hanover, Germany. A simple cuboid wooden barge of constant density is examined. The motion of the barge in various waves, ranging from 2cm to 4cm in wave height and from 0.8s to 2.4s in wave period is tracked. The configuration of the set-up varies from a soft-mooring-system, ensuring free motion of the structure, to a traditional mooring system. The system includes springs of different material parameters representing the elasticity of the mooring system in a slack and a taut configuration and catenary mooring comprised of a small metal chain. The movement is quantified using an OptiTrack Motion-Tracking System composed of four cameras referencing three infra-red markers positioned on the test object. On basis of these experimental results the influence of the mooring system on the motion of the moored-floating barge is evaluated. The experimental data shall be compared to numerical data. For this purpose, the experimental set-up is reproduced in the numerical wave tank of REEF3D. A focus of the study is the investigation of the different mooring models which are available in REEF3D: an analytical approach not considering hydrodynamic forces and a quasi-static model solving the force equilibrium on a discretized line taking into account drag forces

On 2-transitive sets of equiangular lines

All finite sets of equiangular lines spanning finite-dimensional unitary spaces are determined for which the action on the lines of the set-stabilizer in the unitary group is 2-transitive with a regular normal subgroup

Numerical and experimental investigation of floating structures in regular waves

In this paper, an experimental and numerical study of a floating object is presented. The incorporation of both experimental and numerical tools for the investigation of a simple floating object provides the opportunity to validate the proposed numerical model in detail. The experiments are performed in the wave flume of the Leibniz Universit¨at Hannover, Germany. The flume is capable of generating high-fidelity waves with a wide range of parameters. The study consists of a free-floating box which is placed in the middle of the flume. A soft mooring line system is attached to the box in order to prevent motion perpendicular to the incoming wave direction. Heave and pitch motion are measured for different wave heights and periods. Additionally, measurements under consideration of mooring are presented. For this purpose, different rope mooring systems are attached to the box, and the motion of the moored-floating body in different wave conditions is analysed. In a second step, numerical simulations of the same setup are presented. The applied numerical tool is the open-source CFD model REEF3D

Numerical and experimental investigation of floating structures in regular waves

In this paper, an experimental and numerical study of a floating object is presented. The incorporation of both experimental and numerical tools for the investigation of a simple floating object provides the opportunity to validate the proposed numerical model in detail. The experiments are performed in the wave flume of the Leibniz Universit¨at Hannover, Germany. The flume is capable of generating high-fidelity waves with a wide range of parameters. The study consists of a free-floating box which is placed in the middle of the flume. A soft mooring line system is attached to the box in order to prevent motion perpendicular to the incoming wave direction. Heave and pitch motion are measured for different wave heights and periods. Additionally, measurements under consideration of mooring are presented. For this purpose, different rope mooring systems are attached to the box, and the motion of the moored-floating body in different wave conditions is analysed. In a second step, numerical simulations of the same setup are presented. The applied numerical tool is the open-source CFD model REEF3D.acceptedVersio