The Conchoid

The purpose of this thesis is to present 1n a simple and compact manner the conchoid, and to show its use in solving certain mathematical problems. Some of the better known curves related to the conchoid will also be discussed

Designing an information architecture for data management technologies: Introducing the DIAMANT model

Although research institutions take on increased responsibility for providing infrastructures and services around the proper handling of research data, there is no comprehensive framework addressing the ideal conditions of this implementation process. To overcome this gap, we present the DIAMANT model, a reference model aimed at providing an orientation framework for the implementation of research data management guided by the research process itself. It builds upon a central research data management information unit controlling the information flow between all other organizational units involved in research data management. Due to the possibility of outsourcing organizational units, the implementation process is maximally flexible and efficient

The 3-dimensional Fourier grid Hamiltonian method

A method to compute the bound state eigenvalues and eigenfunctions of a Schr\"{o}dinger equation or a spinless Salpeter equation with central interaction is presented. This method is the generalization to the three-dimensional case of the Fourier grid Hamiltonian method for one-dimensional Schr\"{o}dinger equation. It requires only the evaluation of the potential at equally spaced grid points and yields the radial part of the eigenfunctions at the same grid points. It can be easily extended to the case of coupled channel equations and to the case of non-local interactions.Comment: 13 pages, 1 figure. RevTeX file. To appear in J. Comput. Phy

Dynamically generated open charmed baryons beyond the zero range approximation

The interaction of the low lying pseudo-scalar mesons with the ground state baryons in the charm sector is studied within a coupled channel approach using a t-channel vector-exchange driving force. The amplitudes describing the scattering of the pseudo-scalar mesons off the ground-state baryons are obtained by solving the Lippmann--Schwinger equation. We analyze in detail the effects of going beyond the $t=0$ approximation. Our model predicts the dynamical generation of several open charmed baryon resonances in different isospin and strangeness channels, some of which can be clearly identified with recently observed states.Comment: 7 figures, 8 table

Spectrum of low-lying s3QQˉs^{3}Q\bar{Q} configurations with negative parity

Spectrum of low-lying five-quark configurations with strangeness quantum number $S=-3$ and negative parity is studied in three kinds of constituent quark models, namely the one gluon exchange, Goldstone Boson exchange, and instanton-induced hyperfine interaction models, respectively. Our numerical results show that the lowest energy states in all the three employed models are lying at $\sim$1800 MeV, about 200 MeV lower than predictions of various quenched three-quark models. In addition, it is very interesting that the state with the lowest energy in one gluon exchange model is with spin 3/2, but 1/2 in the other two models.Comment: Version published in Phys. Rev.

A mass formula for light mesons from a potential model

The quark dynamics inside light mesons, except pseudoscalar ones, can be quite well described by a spinless Salpeter equation supplemented by a Cornell interaction (possibly partly vector, partly scalar). A mass formula for these mesons can then be obtained by computing analytical approximations of the eigenvalues of the equation. We show that such a formula can be derived by combining the results of two methods: the dominantly orbital state description and the Bohr-Sommerfeld quantization approach. The predictions of the mass formula are compared with accurate solutions of the spinless Salpeter equation computed with a Lagrange-mesh calculation method.Comment: 5 figure

P Wave Meson Spectrum in a Relativistic Model with Instanton Induced Interaction

On the basis of the phenomenological relativistic harmonic models for quarks we have obtained the masses of P wave mesons. The full Hamiltonian used in the investigation has Lorentz scalar + vector confinement potential, along with one gluon exchange potential (OGEP) and the instanton-induced quark-antiquark interaction (III). A good agreement is obtained with the experimental masses. The respective role of III and OGEP for the determination of the meson masses is discussed.Comment: Corrected typo

Wirkungsweise chemischer Nachbehandlungsmittel

Die Nachbehandlung von Beton mit flüssigen (chemischen) Nachbehandlungsmitteln stellt in vielen Fällen eine Alternative zu klassischen Nachbehandlungsarten,wie das Abdecken mit Folie oder das Auflegen von wasserspeichernden Abdeckungen,dar. Hierzu kommen Nachbehandlungsmittel unterschiedlicher chemi-scher Zusammensetzung zum Einsatz, die alle nach dem Auftrageneinen Film bilden, der die Wasserabgabe des Betons reduziert. Je nach Anwendungsgebiet werden unterschiedliche Nachbehandlungsmittel einge-setzt; im Betonstraßenbau sind Nachbehandlungsmittel auf der Basis von Paraffinwachsemulsionenam ver-breitetsten,wogegen bei Estrichen und Industrieböden häufiger Polymerdispersionen eingesetzt werden. Bei allen Nachbehandlungsmitteln ist die richtige Applikationentscheidendfür eine wirksame Nachbehandlung, insbesondere deroptimaleAuftragszeitpunkt spielt dabei eineentscheidende Rolle. Dieser Artikel erläutert die verschiedenen Arten von Nachbehandlungsmitteln, ihre Wirkungsweise sowie Einflüsse auf diese