University of Paderborn

About: University of Paderborn is a education organization based out in Paderborn, Nordrhein-Westfalen, Germany. It is known for research contribution in the topics: Computer science & Context (language use). The organization has 6684 authors who have published 16929 publications receiving 323154 citations.

Quantum optical properties of a single In x Ga 1 − x As − Ga As quantum dot two-level system

Abstract: We report on a two-level system, defined by the ground-state exciton of a single $\mathrm{In}\mathrm{Ga}\mathrm{As}∕\mathrm{Ga}\mathrm{As}$ quantum dot. Saturation spectroscopy combined with ultrahigh spectral resolution gives us a complete description of the system in the steady-state limit. Rabi oscillations and quantum interference experiments, on the other hand, provide a detailed insight into the coherent high excitation regime. All fundamental properties of the two-level system show an excellent quantitative agreement in both domains, even though obtained under entirely different experimental conditions. We thus are able to demonstrate control over an almost ideal two-level system, suitable for possible applications in quantum information processing.

CROWD: An SDN Approach for DenseNets

Abstract: Traffic demands in mobile networks are expected to grow substantially in the next years, both in terms of total traffic volume and of bit-rate required by individual users. It is generally agreed that the only possible solution to overcome the current limitations is to deploy very dense and heterogeneous wireless networks, which we call DenseNets. However, simply scaling down existing networks by orders of magnitude, as required to fulfill traffic forecasts, is not possible because of the following constraints: i) the bottleneck would shift from the Radio Access Network (RAN) to the backhaul, ii) control overhead, especially related to mobility management, would make the network collapse, iii) operational costs of the network would be unbearable due to energy consumption and maintenance/optimisation. In this paper, Software Defined Network (SDN) for mobile networks is claimed as the paradigm shift necessary to tackle adequately the above challenges. A novel architecture is proposed, which supports DenseNets made of overlapping LTE and WLAN cells connected to the core network via a reconfigurable backhaul.

Alkylation of Arenes with Benzylic and Propargylic Alcohols – Classical versus Fancy Catalysts

Abstract: Gold chloride and BF 3 . etherate were tested as Friedel-Crafts catalysts in the propargylation of electron-rich arenes: differences in reactivity of the catalysts can be used to achieve high selectivity either for monoalkylation or for multiple alkylation products. In the case of a macrocyclization towards a heterocalixarene, gold catalysts exhibited a pronounced selectivity, whereas p-toluenesulfonic acid as catalyst opened up a competing pathway to a structural isomer.

The Effectiveness of Recruitment Advertisements and Recruitment Websites: Indirect and Interactive Effects on Applicant Attraction

Abstract: This study compares the effect of printed recruitment advertisements and recruitment websites on applicant attraction and shows how these recruitment activities interact with one another. Our results indicate that websites have a significantly stronger impact on applicant attraction than printed advertisements. We show that websites and printed recruitment advertisements have an indirect effect on applicant attraction that is mediated by employer knowledge. Furthermore, printed advertisements supplement the positive effects of websites and, thus, the simultaneous use of multiple recruitment activities directly influences applicant attraction.

Structural lithium ion battery electrolytes via reaction induced phase-separation

Abstract: For the realization of structural batteries, electrolytes where both higher ionic conductivity and stiffness are combined need to be developed. The present study describes the formation of a struct ...