Fabrication of high quality ferromagnetic Josephson junctions

We present ferromagnetic Nb/Al2O3/Ni60Cu40/Nb Josephson junctions (SIFS) with an ultrathin Al2O3 tunnel barrier. The junction fabrication was optimized regarding junction insulation and homogeneity of current transport. Using ion-beam-etching and anodic oxidation we defined and insulated the junction mesas. The additional 2 nm thin Cu layer below the ferromagnetic NiCu (SINFS) lowered interface roughness and ensured very homogeneous current transport. A high yield of junctional devices with jc spreads less than 2% was obtained.Comment: 5 pages, 6 figures; VORTEX IV conference contribution; Submitted to Physica

On the turbulent friction layer for rising pressure

Among the information presented are included displacement, momentum, and kinetic energy thicknesses, shearing stress distributions across boundary layer, and surface friction coefficients. The Gruschwitz method and its modifications are examined and tested. An energy theorem for the turbulent boundary layer is introduced and discussed but does not lead to a method for the prediction of the behavior of the turbulent boundary layer because relations for the shearing stress and the surface friction are lacking

A novel model for smectic liquid crystals: Elastic anisotropy and response to a steady-state flow

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in J. Chem. Phys. 145, 164903 (2016) and may be found at https://doi.org/10.1063/1.4965711.By means of a combination of equilibrium Monte Carlo and molecular dynamics simulations and nonequilibrium molecular dynamics we investigate the ordered, uniaxial phases (i.e., nematic and smectic A) of a model liquid crystal. We characterize equilibrium behavior through their diffusive behavior and elastic properties. As one approaches the equilibrium isotropic-nematic phase transition, diffusion becomes anisotropic in that self-diffusion D⊥ in the direction orthogonal to a molecule’s long axis is more hindered than self-diffusion D∥ in the direction parallel to that axis. Close to nematic-smectic A phase transition the opposite is true, D∥ < D⊥. The Frank elastic constants K1, K2, and K3 for the respective splay, twist, and bend deformations of the director field n̂ are no longer equal and exhibit a temperature dependence observed experimentally for cyanobiphenyls. Under nonequilibrium conditions, a pressure gradient applied to the smectic A phase generates Poiseuille-like or plug flow depending on whether the convective velocity is parallel or orthogonal to the plane of smectic layers. We find that in Poiseuille-like flow the viscosity of the smectic A phase is higher than in plug flow. This can be rationalized via the velocity-field component in the direction of the flow. In a sufficiently strong flow these smectic layers are not destroyed but significantly bent.DFG, 65143814, GRK 1524: Self-Assembled Soft-Matter Nanostructures at Interface

Оценка времени на прогнозирование технического состояния средств аппаратного контроля

Предлагается метод повышения достоверности функционирования ЭВМ АСУ в условиях воздействия мощных электромагнитных помех (МЭМП), приводятся оценки допустимого времени на прогнозирование технического состояния средств аппаратного контроля (АК) после воздействия мощных электромагнитных помех

Lower Bounds for Ground States of Condensed Matter Systems

Standard variational methods tend to obtain upper bounds on the ground state energy of quantum many-body systems. Here we study a complementary method that determines lower bounds on the ground state energy in a systematic fashion, scales polynomially in the system size and gives direct access to correlation functions. This is achieved by relaxing the positivity constraint on the density matrix and replacing it by positivity constraints on moment matrices, thus yielding a semi-definite programme. Further, the number of free parameters in the optimization problem can be reduced dramatically under the assumption of translational invariance. A novel numerical approach, principally a combination of a projected gradient algorithm with Dykstra's algorithm, for solving the optimization problem in a memory-efficient manner is presented and a proof of convergence for this iterative method is given. Numerical experiments that determine lower bounds on the ground state energies for the Ising and Heisenberg Hamiltonians confirm that the approach can be applied to large systems, especially under the assumption of translational invariance.Comment: 16 pages, 4 figures, replaced with published versio

Kulturelle Bezüge zu außerordentlichen und alltäglichen Landschaften: Zum Verständnis der Konzepte von KULTURLANDSCHAFT seitens deutscher und argentinischer Landbewirtschafter/innen

Diese kontrastive Sprachanalyse untersucht bei zwei Teilnehmergruppen aus der Landwirtschaft abweichende Typisierungen von Landschaften. Die Datenerhebung erfolgte über eine Online-Umfrage. Die unterschiedlichen Verständnisse wurden mittels selbstorganisierender semantischer Karten visualisiert. Es zeigte sich, dass das Wort Kulturlandschaft von der deutschen Gruppe mit den Agrarlandschaften (der eigenen Alltagswelt) und von der argentinischen Gruppe mit den Naturlandschaften (den schützenswerten Urlaubszielen) assoziiert wurde

Congenital Amusia (or Tone-Deafness) Interferes with Pitch Processing in Tone Languages

Congenital amusia is a neurogenetic disorder that affects music processing and that is ascribed to a deficit in pitch processing. We investigated whether this deficit extended to pitch processing in speech, notably the pitch changes used to contrast lexical tones in tonal languages. Congenital amusics and matched controls, all non-tonal language speakers, were tested for lexical tone discrimination in Mandarin Chinese (Experiment 1) and in Thai (Experiment 2). Tones were presented in pairs and participants were required to make same/different judgments. Experiment 2 additionally included musical analogs of Thai tones for comparison. Performance of congenital amusics was inferior to that of controls for all materials, suggesting a domain-general pitch-processing deficit. The pitch deficit of amusia is thus not limited to music, but may compromise the ability to process and learn tonal languages. Combined with acoustic analyses of the tone material, the present findings provide new insights into the nature of the pitch-processing deficit exhibited by amusics

THE URGE TO CHECK SOCIAL NETWORKING SITES: ANTECEDENTS AND CONSEQUENCES

Social networking sites (SNSs), combined with the rapid growth trajectory of mobile devices, and widespread deployment of mobile data services, have evolved as a primary platform for daily social interaction. While the majority of users enjoy frequent interactions with their friends and family members, some users suffer from incessant urges to check up on the lives of others on their social networks. In the last decade, the use of SNSs has received much attention in the IS literature. Not until recently, researchers have begun to examine the dark side of using SNSs. In this study, we attempt to advance existing literature by exploring the role of urges in the context of SNSs. Particularly, we propose a research model that examines the antecedents and consequences of the urge to check SNSs. We will test the model with SNS users using structural equation modeling. We believe that current work will enrich the existing literature on the dark side of SNS use, and raise the awareness in the community regarding this emerging phenomenon

Minimising levelised cost of electricity of bifacial solar panel arrays using Bayesian optimisation

Bifacial solar module technology is a quickly growing market in the photovoltaics PV sector. By utilising light impinging on both, front and back sides of the module, actual limitations of conventional monofacial solar modules can be overcome at almost no additional costs. Optimising large scale bifacial solar power plants with regard to minimum levelised cost of electricity LCOE , however, is challenging due to the vast amount of free parameters such as module inclination angle and distance, module and land costs, character of the surroundings, weather conditions and geographic position. We present a detailed illumination model for bifacial PV modules in a large PV field and calculate the annual energy yield exemplary for two locations with different climates. By applying the Bayesian optimisation algorithm we determine the global minimum of the LCOE for bifacial and monofacial PV fields at these two locations considering land costs in the model. We find that currently established design guidelines for mono and bifacial solar farms often do not yield the minimum LCOE. Our algorithm finds solar panel configurations yielding up to 23 lower LCOE compared to the established configuration with the module tilt angle equal to the latitude and the module distance chosen such that no mutual shading of neighboring solar panels occurs at winter solstice. Our algorithm enables the user to extract clear design guidelines for monoand bifacial large scale solar power plants for most regions on Earth and further accelerates the development of competitively viable photovoltaic system