Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 46 )

2018 ( 281 )

2017 ( 285 )

2016 ( 282 )

Custom range...

Search Results: 1 - 10 of 149590 matches for " H. Heikamp "
All listed articles are free for downloading (OA Articles)
Page 1 /149590
Display every page Item
The electrical signature of rock samples exposed to hydrostatic and triaxial pressures
H. Heikamp,G. Nover
Annals of Geophysics , 2001, DOI: 10.4401/ag-3595
Abstract: The electrical signature of sedimentary (carbonate) and crystalline rock samples was studied in hydrostatic and triaxial pressure experiments up to 300 MPa. The aim was to establish a relation between an electrical signal stimulated by an external pressure acting on the sample and the mechanical stability of the rock. Natural open fractures tend to be closed under hydrostatic pressure conditions, whereas in triaxial pressure experiments new fractures are generated. These contrary processes of either decrease or increase in crack density and geometry, cause a decrease or increase in the inner surface of the sample. Such pressure induced variations in pore geometry were investigated by an interpretation and modelling of the frequency dependence of the complex electrical conductivity. In a series of hydrostatic pressure experiments crack-closure was found in the electrical signature by a decrease of the model capacitor C being related to crack geometry. This capacitor increases in the triaxial experiments where new fractures were formed.
Kindergarten children's attachment security, inhibitory control, and the internalization of rules of conduct
Tobias Heikamp,Gisela Trommsdorff,Michel D. Druey,Ronald Hübner,Antje von Suchodoletz
Frontiers in Psychology , 2013, DOI: 10.3389/fpsyg.2013.00133
Abstract: Starting from research on relations between attachment and the development of self-regulation, the present study aimed to investigate research questions on relations among inhibitory control, internalization of rules of conduct (i.e., behavior regulation, concern occasioned by others transgressions, confession, reparation after wrongdoing), and attachment security. Attachment security and internalization of rules of conduct of German kindergarten children (N = 82) were assessed by maternal reports. Children's inhibitory control was measured with the Stop-task. Regression analyses revealed that inhibitory control was positively related to attachment security and to internalization of rules of conduct. Mediational analysis using a bootstrapping approach indicated an indirect effect of attachment security on internalization processes via inhibitory control. Implications for further research on the development of inhibitory control and internalization of rules of conduct are discussed.
The Mid-infrared E-ELT Imager and Spectrograph (METIS)
Bernhard R. Brandl,Markus Feldt,Alistair Glasse,Manuel Guedel,Stephanie Heikamp,Matthew Kenworthy,Rainer Lenzen,Michael R. Meyer,Frank Molster,Sander Paalvast,Eric J. Pantin,Sascha P. Quanz,Eva Schmalzl,Remko Stuik,Lars Venema,Christoffel Waelkens,the NOVA-Astron Instrumentation Group
Physics , 2014, DOI: 10.1117/12.2056468
Abstract: METIS will be among the first generation of scientific instruments on the E-ELT. Focusing on highest angular resolution and high spectral resolution, METIS will provide diffraction limited imaging and coronagraphy from 3-14um over an 20"x20" field of view, as well as integral field spectroscopy at R ~ 100,000 from 2.9-5.3um. In addition, METIS provides medium-resolution (R ~ 5000) long slit spectroscopy, and polarimetric measurements at N band. While the baseline concept has already been discussed, this paper focuses on the significant developments over the past two years in several areas: The science case has been updated to account for recent progress in the main science areas circum-stellar disks and the formation of planets, exoplanet detection and characterization, Solar system formation, massive stars and clusters, and star formation in external galaxies. We discuss the developments in the adaptive optics (AO) concept for METIS, the telescope interface, and the instrument modelling. Last but not least, we provide an overview of our technology development programs, which ranges from coronagraphic masks, immersed gratings, and cryogenic beam chopper to novel approaches to mirror polishing, background calibration and cryo-cooling. These developments have further enhanced the design and technology readiness of METIS to reliably serve as an early discovery machine on the E-ELT.
Euler-Lagrange Elasticity: Differential Equations for Elasticity without Stress or Strain  [PDF]
H. H. Hardy
Journal of Applied Mathematics and Physics (JAMP) , 2013, DOI: 10.4236/jamp.2013.17004

Differential equations to describe elasticity are derived without the use of stress or strain. The points within the body are the independent parameters instead of strain and surface forces replace stress tensors. These differential equations are a continuous analytical model that can then be solved using any of the standard techniques of differential equations. Although the equations do not require the definition stress or strain, these quantities can be calculated as dependent parameters. This approach to elasticity is simple, which avoids the need for multiple definitions of stress and strain, and provides a simple experimental procedure to find scalar representations of material properties in terms of the energy of deformation. The derived differential equations describe both infinitesimal and finite deformations.

Euler-Lagrange Elasticity with Dynamics  [PDF]
H. H. Hardy
Journal of Applied Mathematics and Physics (JAMP) , 2014, DOI: 10.4236/jamp.2014.213138
Abstract: The equations of Euler-Lagrange elasticity describe elastic deformations without reference to stress or strain. These equations as previously published are applicable only to quasi-static deformations. This paper extends these equations to include time dependent deformations. To accomplish this, an appropriate Lagrangian is defined and an extrema of the integral of this Lagrangian over the original material volume and time is found. The result is a set of Euler equations for the dynamics of elastic materials without stress or strain, which are appropriate for both finite and infinitesimal deformations of both isotropic and anisotropic materials. Finally, the resulting equations are shown to be no more than Newton's Laws applied to each infinitesimal volume of the material.
Linear Algebra Provides a Basis for Elasticity without Stress or Strain  [PDF]
H. H. Hardy
Soft (Soft) , 2015, DOI: 10.4236/soft.2015.43003
Abstract: Linear algebra provides insights into the description of elasticity without stress or strain. Classical descriptions of elasticity usually begin with defining stress and strain and the constitutive equations of the material that relate these to each other. Elasticity without stress or strain begins with the positions of the points and the energy of deformation. The energy of deformation as a function of the positions of the points within the material provides the material properties for the model. A discrete or continuous model of the deformation can be constructed by minimizing the total energy of deformation. As presented, this approach is limited to hyper-elastic materials, but is appropriate for infinitesimal and finite deformations, isotropic and anisotropic materials, as well as quasi-static and dynamic responses.
Spectral resolution in hyperbolic orbifolds, quantum chaos, and cosmology
H. Then
Physics , 2007,
Abstract: We present a few subjects from physics that have one in common: the spectral resolution of the Laplacian.
Arithmetic quantum chaos of Maass waveforms
H. Then
Mathematics , 2003,
Abstract: We compute numerically eigenvalues and eigenfunctions of the quantum Hamiltonian that describes the quantum mechanics of a point particle moving freely in a particular three-dimensional hyperbolic space of finite volume and investigate the distribution of the eigenvalues.
Maass cusp forms for large eigenvalues
H. Then
Mathematics , 2003,
Abstract: We investigate the numerical computation of Maass cusp forms for the modular group corresponding to large eigenvalues. We present Fourier coefficients of two cusp forms whose eigenvalues exceed r=40000. These eigenvalues are the largest that have so far been found in the case of the modular group. They are larger than the 130millionth eigenvalue.
Static Electric-Spring and Nonlinear Oscillations  [PDF]
H. Sarafian
Journal of Electromagnetic Analysis and Applications (JEMAA) , 2010, DOI: 10.4236/jemaa.2010.22011
Abstract: The author designed a family of nonlinear static electric-springs. The nonlinear oscillations of a massively charged particle under the influence of one such spring are studied. The equation of motion of the spring-mass system is highly nonlinear. Utilizing Mathematica [1] the equation of motion is solved numerically. The kinematics of the particle namely, its position, velocity and acceleration as a function of time, are displayed in three separate phase diagrams. Energy of the oscillator is analyzed. The nonlinear motion of the charged particle is set into an actual three-dimensional setting and animated for a comprehensive understanding.
Page 1 /149590
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.