Neutrino Detection, Position Calibration and Marine Science with Acoustic Arrays in the Deep Sea

Arrays of acoustic receivers are an integral part of present and potential future Cherenkov neutrino telescopes in the deep sea. They measure the positions of individual detector elements which vary with time as an effect of undersea currents. At the same time, the acoustic receivers can be employed for marine science purposes, in particular for monitoring the ambient noise environment and the signals emitted by the fauna of the sea. And last but not least, they can be used for studies towards acoustic detection of ultra-high-energy neutrinos. Measuring acoustic pressure pulses in huge underwater acoustic arrays with an instrumented volume of the order of 100 km^3 is a promising approach for the detection of cosmic neutrinos with energies exceeding 1 EeV. Pressure signals are produced by the particle cascades that evolve when neutrinos interact with nuclei in water, and can be detected over large distances in the kilometre range. In this article, the status of acoustic detection will be reviewed and plans for the future - most notably in the context of KM3NeT - will be discussed. The connection between neutrino detection, position calibration and marine science will be illustrated.Comment: Contribution to the Proceedings of the 5th workshop on very large volume neutrino telescopes (VLV{\nu}T 11) in Erlangen, Germany, 12 -14 October 201

trends and confounding

Ergebnisse zur Dekubitusprävalenz sind wichtige Indikatoren für das Ausmaß der Erkrankung in unterschiedlichen Sektoren und Bereichen des deutschen Gesundheitswesens. Valide und präzise Zahlen zur Prävalenz sind zur Bewertung des Ressourcenbedarfs und Planung von Gesundheitsleistungen dringend erforderlich. Durch die vorliegenden Studien kann das Ausmaß der Dekubitushäufigkeit in bundesdeutschen Pflegeheimen und Krankenhäusern bestimmt werden. Es bestehen Hinweise, dass von einer externen Validität der Studienergebnisse ausgegangen werden kann. Dabei muss die bisherig angenommene hohe Prävalenz von 30% in Pflegeheimen deutlich nach unten korrigiert werden. Die standardisierten jährlichen Erhebungen lassen den Schluss zu, dass sich die Dekubitusprävalenz seit 2001 sowohl in Pflegeheimen als auch in Krankenhäusern reduziert hat. War vor 10 Jahren noch jeder zehnte Bewohner/ Patient von Dekubitus betroffen, so ist es im Jahre 2011 nur noch jeder 20. Kranken-hauspatient und nur noch jeder 25. Pflegeheimbewohner. Der Vergleich von institutsbezogener Prävalenz sollte ausschließlich risikoadjustiert erfolgen, da nur dadurch faire Vergleiche zwischen unterschiedlichen Sektoren, Bereichen und Einrichtungen möglich sind und der Einfluss von Confoundern weitestgehend reduziert wird. Die durchgeführten Studien ermöglichen die Weiterentwicklung von statistischen Modellen. Analog zu dem im Rahmen dieser Studie vorgestellten SRISAG Modell sollten derartige Modelle einfach und handhabbar sein und dadurch eine sinnvolle Problem- und Qualitätsbestimmung des Pflegeproblems Dekubitus in unterschiedlichen Institutionen des deutschen Gesundheitswesens ermöglichen.Results of studies about pressure ulcer prevalence are important parameters about the size of the problem in different sectors and areas of the German health care services, because valid and precise figures about its prevalence are necessary for the adequate planning of actual care needs. The provided studies of this Habilitation provide this information for German Hospitals and nursing homes. The results can be considered as sufficiently external valid. Former estimation of a high pressure ulcer prevalence of about 30 percent in German nursing homes have to be adjusted downwards notably. The standardized annual studies lead to the conclusion, that the pressure ulcer prevalence has dropped since 2001 in nursing homes and hospitals. Ten years ago, every 10th hospital patient and nursing home resident had at least one pressure ulcer. In the year 2011 this is only the case in every 20th hospital patient and every 25th nursing home residents. The comparison of institutional related prevalence rates should always be done by applying risk adjustment measures. Thus fair comparison between different sectors, areas and institutions will be guaranteed and the influence of possible confounders will be minimized. The preformed studies allow the further development of statistical models. Alike the in this habilitation proposed SRISAG-Modell, these models should be easy and manageable and can be used to determine the size of the problem and the quality of the nursing problem pressure ulcer in different institutions of the German health care system

Simulation and Analysis Chain for Acoustic Ultra-high Energy Neutrino Detectors in Water

Acousticneutrinodetectionisapromisingapproachforlarge-scaleultra-highenergyneutrinodetectorsinwater.In this article, a Monte Carlo simulation chain for acoustic neutrino detection devices in water will be presented. The simulation chain covers the generation of the acoustic pulse produced by a neutrino interaction and its propagation to the sensors within the detector. Currently, ambient and transient noise models for the Mediterranean Sea and simulations of the data acquisition hardware, equivalent to the one used in ANTARES/AMADEUS, are implemented. A pre-selection scheme for neutrino-like signals based on matched filtering is employed, as it is used for on-line filtering. To simulate the whole processing chain for experimental data, signal classification and acoustic source reconstruction algorithms are integrated in an analysis chain. An overview of design and capabilities of the simulation and analysis chain will be presented and preliminary studies will be discussed.Comment: 6 pages, 5 figures, ARENA 2012. arXiv admin note: substantial text overlap with arXiv:1304.057

Tax Shield, Insolvenz und Zinsschranke

Dieser Beitrag analysiert den Wertbeitrag fremdfinanzierungsbedingter Steuervorteile (Tax Shield) unter realistischen Bedingungen (keine Negativsteuer; mögliche Insolvenz) für unterschiedliche Finanzierungspolitiken. Zusätzlich wird der Effekt der sogenannten Zinsschranke auf den Wert des Tax Shield ermittelt. Die Bewertung des Tax Shield mit und ohne Zinsschranke findet im einperiodigen Fall auf der Basis von Optionspreismodellen und im mehrperiodigen Fall auf der Basis von Monte Carlo Simulationsmodellen statt. Dabei wird unter idealen Annahmen die Kovergenz zu den Textbook - Gleichungen nach Modigliani/Miller bzw. Miles/Ezzell hergestellt. Es zeigt sich, dass die Einführung einer möglichen Insolvenz zu deutlichen Abweichungen der Werte von den Textbook - Werten führt. Dagegen ist der zusätzliche Effekt der Zinsschranke für beide Finanzierungspolitiken zu vernachlässigen

Development of Combined Opto-Acoustical Sensor Modules

The faint fluxes of cosmic neutrinos expected at very high energies require large instrumented detector volumes. The necessary volumes in combination with a sufficient shielding against background constitute forbidding and complex environments (e.g. the deep sea) as sites for neutrino telescopes. To withstand these environments and to assure the data quality, the sensors have to be reliable and their operation has to be as simple as possible. A compact sensor module design including all necessary components for data acquisition and module calibration would simplify the detector mechanics and ensures the long term operability of the detector. The compact design discussed here combines optical and acoustical sensors inside one module, therefore reducing electronics and additional external instruments for calibration purposes. In this design the acoustical sensor is primary used for acoustic positioning of the module. The module may also be used for acoustic particle detection and marine science if an appropriate acoustical sensor is chosen. First tests of this design are promising concerning the task of calibration. To expand the field of application also towards acoustic particle detection further improvements concerning electromagnetic shielding and adaptation of the single components are necessary.Comment: 4 pages, 2 figures, ARENA2010 proceeding

Thermo-acoustic Sound Generation in the Interaction of Pulsed Proton and Laser Beams with a Water Target

The generation of hydrodynamic radiation in interactions of pulsed proton and laser beams with matter is explored. The beams were directed into a water target and the resulting acoustic signals were recorded with pressure sensitive sensors. Measurements were performed with varying pulse energies, sensor positions, beam diameters and temperatures. The obtained data are matched by simulation results based on the thermo-acoustic model with uncertainties at a level of 10%. The results imply that the primary mechanism for sound generation by the energy deposition of particles propagating in water is the local heating of the medium. The heating results in a fast expansion or contraction and a pressure pulse of bipolar shape is emitted into the surrounding medium. An interesting, widely discussed application of this effect could be the detection of ultra-high energetic cosmic neutrinos in future large-scale acoustic neutrino detectors. For this application a validation of the sound generation mechanism to high accuracy, as achieved with the experiments discussed in this article, is of high importance.Comment: 12 pages, 15 figure

Measurements and Simulation Studies of Piezoceramics for Acoustic Particle Detection

Calibration sources are an indispensable tool for all detectors. In acoustic particle detection the goal of a calibration source is to mimic neutrino signatures as expected from hadronic cascades. A simple and promising method for the emulation of neutrino signals are piezo ceramics. We will present results of measruements and simulations on these piezo ceramics.Comment: 5 pages, 5 figure

Zinsschranke, Unternehmensbewertung und APV Ansatz - eine Anmerkung zum Beitrag von Förster/Stöckl/Brenken (ZfB 2009, S. 985 ff.)

In einem kürzlich erschienenen ZfB-Beitrag schlagen Förster et al. eine Vorgehensweise für die Erfassung der Zinsschranke und ihrer Wirkung auf die zinsinduzierte Steuerersparnis vor. Dieser Beitrag nimmt kritisch dazu Stellung: Es wird gezeigt, dass die dort abgeleiteten Formeln für die Steuerersparnisse nicht konsistent sind und bei positiven Zinsaufwendungen negative Steuerersparnisse zulassen. Die von den Autoren vorgeschlagene Aufspaltung der Steuerersparnisse ist u.E. nicht geeignet die Komplexität des Bewertungsproblems zu verringern: Die Schätzung der erwarteten Steuerersparnisse für die zweite Komponente setzt die Kenntnis der möglichen Entwicklungspfade der Steuerersparnis voraus. Die vorgeschlagene Aufteilung erhöht die Anzahl der zusätzlich zu schätzenden Diskontierungssätze. Schließlich setzt die Ableitung der risikoäquivalenten Diskontierungssätze die Kenntnis des Wertbeitrages bereits voraus.The German 'Zinsschranke' limits the tax deductability of interest expenses. Recently, in this journal Förster et al. have developed a model to incorporate this tax regulation into the calculation of the tax shield in corporate valuation. Our paper critically comments on this proposal

Signal Classification for Acoustic Neutrino Detection

This article focuses on signal classification for deep-sea acoustic neutrino detection. In the deep sea, the background of transient signals is very diverse. Approaches like matched filtering are not sufficient to distinguish between neutrino-like signals and other transient signals with similar signature, which are forming the acoustic background for neutrino detection in the deep-sea environment. A classification system based on machine learning algorithms is analysed with the goal to find a robust and effective way to perform this task. For a well-trained model, a testing error on the level of one percent is achieved for strong classifiers like Random Forest and Boosting Trees using the extracted features of the signal as input and utilising dense clusters of sensors instead of single sensors.Comment: 8 Pages, 6 Figures, ARENA 2010 Conference Proceeding