1,081 research outputs found

    Informationsmanagement und Transformationsaufwand im Gebäudemanagement [online]

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    Die Informationsverarbeitung hat in modernen Industriegesellschaften einen zentralen Stellenwert. Aktuelle Informationen bilden für jede Entscheidung und jeden Prozessablauf eine wichtige Grundlage für eine sinnvolle und effiziente Leistungserbringung. Vorteilig wirkt sich dabei aus, dass Informationen beliebig vermehrbar sind ohne verbraucht zu werden. In der Praxis stellen sie allerdings eine Restriktion dar, wenn der Informationsbedarf ungewollt oder bewusst nicht entsprechend den Nutzungsanforderungen zur Verfügung gestellt wird. Informationen haben somit einen entscheidenden Einfluss auf den Grad und Qualität der Arbeitsteilung innerhalb von Organisationen und Volkswirtschaften. Diese Erkenntnis ist in den vergangenen Jahren von der Wissenschaft verstärkt thematisiert worden. Das Ergebnis lässt sich diesbezüglich in den zahlreichen Bibliographien ablesen, die Konzepte zur Informationsverarbeitung beschreiben. Gemeinsam ist den Veröffentlichungen, dass sie den theoretisch optimalen Endzustand der Informationsverarbeitung darstellen ohne Bezug auf die Realisierung in situ zu nehmen. Charakterisierend ist, dass die Realisierung regelmäßig als \u27Projekt\u27 bezeichnet wird und damit der zeitliche und personelle Rahmen fixiert ist. Unberücksichtigt bleibt die vorhandene Informationsverarbeitung, die in Organisationen über Jahre gewachsen ist und von den Mitgliedern verinnerlicht wurde. Innerhalb der vorliegenden Arbeit werden die Konzepte zur Informationsverarbeitung nicht weiter fortgeschrieben. Die Forschungsarbeit konzentriert sich auf die Realisierung der Konzepte unter realen Bedingungen. Dazu wird im ersten Schritt ein integrales Informationsmanagement als Managementsystem erarbeitet, wie es nach der Evaluierung der Anforderungen aus der aufgabenübergreifenden Informationsverarbeitung definiert ist. Darüber hinaus wird die organisatorische Einbindung entwickelt, um die erforderliche Akzeptanz und Praxisorientierung zu gewährleisten. Zur erstmaligen Erreichung des Zielsystems beinhaltet die Arbeit ein Realisierungskonzept, das auch spätere Anpassungsmaßnahmen berücksichtigt. Das Konzept beinhaltet Handlungshilfen zur Identifikation von Daten und Prozessen, zur Realisierung einer einheitlichen Daten- und Prozessbasis sowie zur Modellierung des SOLL-Systems unter der Berücksichtigung realer Bedingungen. Die erforderliche deskriptive Darstellung, die die existierenden/notwendigen Daten und Prozesse organisationsspezifisch und synoptisch abbildet, wird hergeleitet und begründet. Abschließend wird der zeitliche Transformationsaufwand zur Umsetzung des entwickelten Realisierungskonzeptes auf Basis von wissenschaftlich begleiteten Reorganisationsmaßnahmen an der Universität Karlsruhe dargestellt und analysiert. Der abgeleitete Berechnungsansatz soll den interessierten und kritischen Leser bei der Planung von vergleichbaren Maßnahmen unterstützen

    Riemannian tangent space mapping and elastic net regularization for cost-effective EEG markers of brain atrophy in Alzheimer's disease

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    The diagnosis of Alzheimer's disease (AD) in routine clinical practice is most commonly based on subjective clinical interpretations. Quantitative electroencephalography (QEEG) measures have been shown to reflect neurodegenerative processes in AD and might qualify as affordable and thereby widely available markers to facilitate the objectivization of AD assessment. Here, we present a novel framework combining Riemannian tangent space mapping and elastic net regression for the development of brain atrophy markers. While most AD QEEG studies are based on small sample sizes and psychological test scores as outcome measures, here we train and test our models using data of one of the largest prospective EEG AD trials ever conducted, including MRI biomarkers of brain atrophy.Comment: Presented at NIPS 2017 Workshop on Machine Learning for Healt

    Origin and transformation of light hydrocarbons ascending at an active pockmark on Vestnesa Ridge, Arctic Ocean

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    We report on the geochemistry of hydrocarbons and pore waters down to 62.5 mbsf, collected by drilling with the MARUM‐MeBo70 and by gravity coring at the Lunde pockmark in the Vestnesa Ridge. Our data document the origin and transformations of volatiles feeding gas emissions previously documented in this region. Gas hydrates are present where a fracture network beneath the pockmark focusses migration of thermogenic hydrocarbons characterized by their C1/C2+ and stable isotopic compositions (δ2H‐CH4, δ13C‐CH4). Measured geothermal gradients (~80°C km‐1) and known formation temperatures (>70°C) suggest that those hydrocarbons are formed at depths >800 mbsf. A combined analytical/modeling approach, including concentration and isotopic mass balances, reveals that pockmark sediments experience diffuse migration of thermogenic hydrocarbons. However, at sites without channeled flow this appears to be limited to depths > ~50 mbsf. At all sites we document a contribution of microbial methanogenesis to the overall carbon cycle that includes a component of secondary carbonate reduction (CR) – i.e. reduction of dissolved inorganic carbon (DIC) generated by anaerobic oxidation of methane (AOM) in the uppermost methanogenic zone. AOM and CR rates are spatially variable within the pockmark and are highest at high‐flux sites. These reactions are revealed by δ13C‐DIC depletions at the sulfate‐methane interface at all sites. However, δ13C‐CH4 depletions are only observed at the low methane flux sites because changes in the isotopic composition of the overall methane pool are masked at high‐flux sites. 13C‐depletions of TOC suggest that at seeps sites, methane‐derived carbon is incorporated into de novo synthesized biomass

    Inhomogeneous Metal Distribution in the Intra-Cluster Medium

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    The hot gas that fills the space between galaxies in clusters is rich in metals. In their large potential wells, galaxy clusters accumulate metals over the whole cluster history and hence they retain important information on cluster formation and evolution. We use a sample of 5 cool core clusters to study the distribution of metals in the ICM. We investigate whether the X-ray observations yield good estimates for the metal mass and whether the heavy elements abundances are consistent with a certain relative fraction of SN Ia to SNCC. We derive detailed metallicity maps of the clusters from XMM - Newton observations and we use them as a measure for the metal mass in the ICM. We determine radial profiles for several elements and using population synthesis and chemical enrichment models, we study the agreement between the measured abundances and the theoretical yields. We show that even in relaxed clusters the distribution of metals show a lot of inhomogeneities. Using metal maps usually gives a metal mass 10-30% higher than the metal mass computed using a single extraction region, hence it is expected that most previous metal mass determination have underestimated metal mass. The abundance ratio of {\alpha}-elements to Fe, even in the central parts of clusters, are consistent with an enrichment due to the combination of SN Ia and SNCC

    Long-term unsupervised mobility assessment in movement disorders

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    Mobile health technologies (wearable, portable, body-fixed sensors, or domestic-integrated devices) that quantify mobility in unsupervised, daily living environments are emerging as complementary clinical assessments. Data collected in these ecologically valid, patient-relevant settings can overcome limitations of conventional clinical assessments, as they capture fluctuating and rare events. These data could support clinical decision making and could also serve as outcomes in clinical trials. However, studies that directly compared assessments made in unsupervised and supervised (eg, in the laboratory or hospital) settings point to large disparities, even in the same parameters of mobility. These differences appear to be affected by psychological, physiological, cognitive, environmental, and technical factors, and by the types of mobilities and diagnoses assessed. To facilitate the successful adaptation of the unsupervised assessment of mobility into clinical practice and clinical trials, clinicians and researchers should consider these disparities and the multiple factors that contribute to them

    Suppression of quantum oscillations and the dependence on site energies in electronic excitation transfer in the Fenna-Matthews-Olson trimer

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    Energy transfer in the photosynthetic complex of the Green Sulfur Bacteria known as the Fenna-Matthews-Olson (FMO) complex is studied theoretically taking all three subunits (monomers) of the FMO trimer and the recently found eighth bacteriochlorophyll (BChl) molecule into account. We find that in all considered cases there is very little transfer between the monomers. Since it is believed that the eighth BChl is located near the main light harvesting antenna we look at the differences in transfer between the situation when BChl 8 is initially excited and the usually considered case when BChl 1 or 6 is initially excited. We find strong differences in the transfer dynamics, both qualitatively and quantitatively. When the excited state dynamics is initialized at site eight of the FMO complex, we see a slow exponential-like decay of the excitation. This is in contrast to the oscillations and a relatively fast transfer that occurs when only seven sites or initialization at sites 1 and 6 is considered. Additionally we show that differences in the values of the electronic transition energies found in the literature lead to a large difference in the transfer dynamics

    Metal enrichment processes

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    There are many processes that can transport gas from the galaxies to their environment and enrich the environment in this way with metals. These metal enrichment processes have a large influence on the evolution of both the galaxies and their environment. Various processes can contribute to the gas transfer: ram-pressure stripping, galactic winds, AGN outflows, galaxy-galaxy interactions and others. We review their observational evidence, corresponding simulations, their efficiencies, and their time scales as far as they are known to date. It seems that all processes can contribute to the enrichment. There is not a single process that always dominates the enrichment, because the efficiencies of the processes vary strongly with galaxy and environmental properties.Comment: 18 pages, 8 figures, accepted for publication in Space Science Reviews, special issue "Clusters of galaxies: beyond the thermal view", Editor J.S. Kaastra, Chapter 17; work done by an international team at the International Space Science Institute (ISSI), Bern, organised by J.S. Kaastra, A.M. Bykov, S. Schindler & J.A.M. Bleeke

    Upper limits on the strength of periodic gravitational waves from PSR J1939+2134

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    The first science run of the LIGO and GEO gravitational wave detectors presented the opportunity to test methods of searching for gravitational waves from known pulsars. Here we present new direct upper limits on the strength of waves from the pulsar PSR J1939+2134 using two independent analysis methods, one in the frequency domain using frequentist statistics and one in the time domain using Bayesian inference. Both methods show that the strain amplitude at Earth from this pulsar is less than a few times 102210^{-22}.Comment: 7 pages, 1 figure, to appear in the Proceedings of the 5th Edoardo Amaldi Conference on Gravitational Waves, Tirrenia, Pisa, Italy, 6-11 July 200

    Improving the sensitivity to gravitational-wave sources by modifying the input-output optics of advanced interferometers

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    We study frequency dependent (FD) input-output schemes for signal-recycling interferometers, the baseline design of Advanced LIGO and the current configuration of GEO 600. Complementary to a recent proposal by Harms et al. to use FD input squeezing and ordinary homodyne detection, we explore a scheme which uses ordinary squeezed vacuum, but FD readout. Both schemes, which are sub-optimal among all possible input-output schemes, provide a global noise suppression by the power squeeze factor, while being realizable by using detuned Fabry-Perot cavities as input/output filters. At high frequencies, the two schemes are shown to be equivalent, while at low frequencies our scheme gives better performance than that of Harms et al., and is nearly fully optimal. We then study the sensitivity improvement achievable by these schemes in Advanced LIGO era (with 30-m filter cavities and current estimates of filter-mirror losses and thermal noise), for neutron star binary inspirals, and for narrowband GW sources such as low-mass X-ray binaries and known radio pulsars. Optical losses are shown to be a major obstacle for the actual implementation of these techniques in Advanced LIGO. On time scales of third-generation interferometers, like EURO/LIGO-III (~2012), with kilometer-scale filter cavities, a signal-recycling interferometer with the FD readout scheme explored in this paper can have performances comparable to existing proposals. [abridged]Comment: Figs. 9 and 12 corrected; Appendix added for narrowband data analysi
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