Suchergebnisse

Auch das Personalmanagement im Krankenhaus wandelt sich. Die demografischen Veränderungen, die Finanzierung des Pflegedienstes, Pflegepersonaluntergrenzen und die in der Medizin zunehmende Digitalisierung sind Grund genug, die etablierte Publikation "Personalmanagement im Krankenhaus" mit einer fünften Auflage zu aktualisieren und zu erweitern. Die vorliegende Publikation richtet sich insbesondere an Führungskräfte und Führungsnachwuchskräfte im Gesundheitswesen, da zunehmend Vorgesetzte das operative Personalmanagement tragen und umsetzen.

Die Kompensierung von Erwerbseinkommensverlusten, der Ausgleich gesellschaftlich anerkannter Schutztatbestände und die Bekämpfung von Armut sind grundlegende Ziele der sozialen Sicherung. Diese Ziele können mit unterschiedlichen Instrumenten angestrebt werden, worunter staatlich monetäre Sozialleistungen eine besondere Rolle spielen. Die USA und die Bundesrepublik sind Vertreter unterschiedlicher Vorgehensweisen auf diesem Gebiet der Sozialpolitik. Dieser Sachverhalt wird durch eine Synopse ausgewählter Programme der sozialen Sicherung mit monetären Leistungen in den USA und der Bundesrepublik Deutschland erhellt. Eine Tabelle mit exemplarischen Sozialleistungsbeiträgen pro Monat und dem durchschnittlichen monatlichen Bruttoverdienst eine Industriearbeiters in den USA und der Bundesrepublik rundet das Bild ab. (ICD)

We implement a method to identify the deterministic nature of specific events in the dynamics of a semiconductor laser subject to time-delayed optical feedback. Specifically, we study the power dropouts in the low-frequency fluctuations regime on an individual event basis and identify whether the underlying dominant mechanism is deterministic. Our approach is based on sychronization with a twin system in a symmetric relay configuration. We investigate the dependence of the fraction of deterministically driven (i.e., synchronized) dropouts on the laser's pump current as a key parameter. Our experimental results are corroborated by numerical modeling based on rate equations. Our numerical findings also provide insights into the influence of spontaneous emission noise. © 2013 American Physical Society. ; This work was supported by MICINN (Spain) under Project TEC2009-14101 (DeCoDicA), by MINECO (Spain) under Project TEC2012-36335 (TRIPHOP), by the Government of the Balearic Islands within Grups Competitius, and by the European Commission under EC FP7 Project PHOCUS (Grant No. 240763). K.H. acknowledges financial support from the Government of the Balearic Islands (Department of Education, Culture, and Universities), cofunded by the European Social Fund. ; Peer Reviewed

In diesem Beitrag behandeln die Autoren Arbeitslosigkeit als eine zunehmende Ursache von Verarmung und Angewiesensein auf Sozialhilfe. Hier wird dargestellt, durch welche wirtschaftlichen, vor allem aber auch gesetzgeberischen und administrativen Änderungen (Sozialabbau), die kommunale Sozialhilfe zum haftenden Ausfallbürgen gegenüber dem in der Krise eingeschränkten zentralen Sicherungssystem wurde und wie die Gemeinden das für sie an sich unbewältigbare Risiko auffangen oder abzuschieben suchen. Der Schwerpunkt der Untersuchung liegt in dem erstmals in dieser Form unternommenen Versuch, die insgesamt unzulängliche amtliche Statistik so auszuweiten oder zu ergänzen, daß sie quantitative Aussagen über den Problemumfang gestattet. Dabei wird auch das Verhältnis von untersten Arbeitnehmereinkommen und Sozialhilfebedürftigkeit untersucht. (GF2)

The efficacy of data decoding in contemporary ultrafast fiber transmission systems is greatly determined by the capabilities of the signal processing tools that are used. The received signal must not exceed a certain level of complexity, beyond which the applied signal processing solutions become insufficient or slow. Moreover, the required signal-to-noise ratio (SNR) of the received signal can be challenging, especially when adopting modulation formats with multi-level encoding. Lately, photonic reservoir computing (RC)-a hardware machine learning technique with recurrent connectivity-has been proposed as a post-processing tool that deals with deterministic distortions from fiber transmission. Here, we show that RC post-processing is remarkably efficient for multilevel encoding and for the use of very high launched optical peak power for fiber transmission up to 14 dBm. Higher power levels provide the desired high SNR values at the receiver end, at the expense of a complex nonlinear transformation of the transmission signal. Our demonstration evaluates a direct fiber communication link with 4-level pulse amplitude modulation (PAM-4) encoding and direct detection, without including optical amplification, dispersion compensation, pulse shaping or other digital signal processing (DSP) techniques. By applying RC post-processing on the distorted signal, we numerically estimate fiber transmission distances of 27 km at 56 Gb/s and of 5.5 km at 112 Gb/s data encoding rates, while fulfilling the hard-decision forward error correction (HD-FEC) bit-error-rate (BER) limit for data recovery. In an experimental equivalent demonstration of our photonic reservoir, the achieved distances are 21 and 4.6 km, respectively. ; This work was supported in part by the Ministerio de Economía y Competitividad and FEDER via project IDEA under Grant TEC2016-80063-C3, and in part by the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie project CENTURION under Contract 707068. ; Peer reviewed

Machine learning techniques have proven very efficient in assorted classification tasks. Nevertheless, processing time-dependent high-speed signals can turn into an extremely challenging task, especially when these signals have been nonlinearly distorted. Recently, analogue hardware concepts using nonlinear transient responses have been gaining significant interest for fast information processing. Here, we introduce a simplified photonic reservoir computing scheme for data classification of severely distorted optical communication signals after extended fibre transmission. To this end, we convert the direct bit detection process into a pattern recognition problem. Using an experimental implementation of our photonic reservoir computer, we demonstrate an improvement in bit-error-rate by two orders of magnitude, compared to directly classifying the transmitted signal. This improvement corresponds to an extension of the communication range by over 75%. While we do not yet reach full real-time post-processing at telecom rates, we discuss how future designs might close the gap. ; This work was supported by the Ministerio de Economía y Competitividad and FEDER via project IDEA (TEC2016-80063-C3), and by the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie contract 707068. ; Peer reviewed

We consider the behavior of Stuart–Landau oscillators as generic limit-cycle oscillators when they are interacting with delay. We investigate the role of amplitude and phase instabilities in producing symmetry-breaking/restoring transitions. Using analytical and numerical methods we compare the dynamics of one oscillator with delayed feedback, two oscillators mutually coupled with delay, and two delay-coupled elements with self-feedback. Taking only the phase dynamics into account, no chaotic dynamics is observed, and the stability of the identical synchronization solution is the same in each of the three studied networks of delay-coupled elements. When allowing for a variable oscillation amplitude, the delay can induce amplitude instabilities. We provide analytical proof that, in case of two mutually coupled elements, the onset of an amplitude instability always results in antiphase oscillations, leading to a leader-laggard behavior in the chaotic regime. Adding selffeedback with the same strength and delay as the coupling stabilizes the system in the transverse direction and, thus, promotes the onset of identically synchronized behavior ; We would like to thank T. Erneux, E. Schöll, S. Yanchuk, and P. Perlikowski for helpful discussions. O.D. acknowledges the Research Foundation Flanders FWO-Vlaanderen for a fellowship and for project support. This work was partially supported by the Interuniversity Attraction Poles program of the Belgian Science Policy Office, under Grant No. IAP VI-10 "photonics@be," by MICINN Spain under project DeCoDicA Grant No. TEC2009- 14101 ,, and by the project PHOCUS EU FET Open Grant No. 240763 . ; Peer reviewed

Semiconductor lasers can exhibit complex dynamical behavior in the presence of external perturbations. Delayed optical feedback, re-injecting part of the emitted light back into the laser cavity, in particular, can destabilize the laser's emission. We focus on the emission properties of a semiconductor laser subject to such optical feedback, where the delay of the light re-injection is large compared to the relaxation oscillations period. We present an overview of the main dynamical features that emerge in semiconductor lasers subject to delayed optical feedback, emphasizing how to experimentally characterize these features using intensity and high-resolution optical spectra measurements. The characterization of the system requires the experimentalist to be able to simultaneously measure multiple time scales that can be up to six orders of magnitude apart, from the picosecond to the microsecond range. We highlight some experimental observations that are particularly interesting from the fundamental point of view and, moreover, provide opportunities for future photonic applications. ; We acknowledge the Spanish State Research Agency, through the Severo Ochoa and María de Maeztu Program for Centers and Units of Excellence in R&D, grant MDM-2017-0711 funded by MCIN/AEI/10.13039/501100011033. X.P. acknowledges funding from the European Union's Horizon 2020 (713694) and the Volkswagen Foundation (NeuroQNet II).

We investigate the dynamics of semiconductor lasers subject to time-delayed optical feedback from the perspective of dynamical self-injection locking. Based on the Lang-Kobayashi model, we perform an analysis of the well-known Low Frequency Fluctuations (LFFs) in the frequency-intensity plane. Moreover, we investigate a recently found dynamical regime of fragmented LFFs by means of a locking-range analysis, spectral comparison and precursor pulse identification. We show that LFF dynamics can be explained by dynamical optical injection locking due to the delayed optical feedback. Moreover, the fragmented LFFs occur due to a re-injection locking induced by a particular optical pulse structure in the chaotic feedback dynamics. This is corroborated by experiments with a semiconductor laser experiencing delayed feedback from an optical fiber loop. The dynamical nature of the feedback injection results in an eventual loss, but also possible regaining, of the locking, explaining the recently observed phenomenon of fragmented LFFs. ; This work was supported by the Spanish Ministerio de Economía, Industria y Competitividad (MINECO), under project Nos. TEC2012–36335, FIS2015–71929-REDT, and TEC2016–80063-C3 (AEI/FEDER, UE). K.H. acknowledges financial support from the Government of the Balearic Islands (Department of Education, Culture, and Universities), co-funded by the European Social Fund. M.C.S. was supported by MINECO through a Ramón y Cajal Fellowship (RYC-2015–18140). D.B. acknowledges support of the CNRS under project No. PICS07300. ; Peer reviewed

Nonlinear photonic delay systems present interesting implementation platforms for machine learning models. They can be extremely fast, offer great degrees of parallelism and potentially consume far less power than digital processors. So far they have been successfully employed for signal processing using the Reservoir Computing paradigm. In this paper we show that their range of applicability can be greatly extended if we use gradient descent with backpropagation through time on a model of the system to optimize the input encoding of such systems. We perform physical experiments that demonstrate that the obtained input encodings work well in reality, and we show that optimized systems perform significantly better than the common Reservoir Computing approach. The results presented here demonstrate that common gradient descent techniques from machine learning may well be applicable on physical neuro-inspired analog computers. ; P.B., M.H. and J.D. acknowledge support by the interuniversity attraction pole (IAP) Photonics@be of the Belgian Science Policy Office, the ERC NaResCo Starting grant and the European Union Seventh Framework Programme under grant agreement no. 604102 (Human Brain Project). M.C.S. and I.F. acknowledge support by MINECO (Spain), Comunitat Autónoma de les Illes Balears, FEDER, and the European Commission under Projects TEC2012-36335 (TRIPHOP), and Grups Competitius. M.H. and I.F. acknowledge support from the Universitat de les Illes Balears for an Invited Young Researcher Grant. ; Peer Reviewed