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  1. Dissertation / Habilitation ; Online: Demand-responsive Disruption Management in Mass Transit Systems

    Blume, Steffen O.P.

    An Agent-Based Simulation Model to Assess Disruptions and Resilience-Enabling Rescheduling Measures

    2021  

    Abstract: Transit systems are indispensable to the growing urban population. However, severe unforeseen and unprecedented disruptions place planners and operators in a position where typical risk mitigation and reliability improvements cease to provide manageable ... ...

    Abstract Transit systems are indispensable to the growing urban population. However, severe unforeseen and unprecedented disruptions place planners and operators in a position where typical risk mitigation and reliability improvements cease to provide manageable solutions. Instead, resilience assessment may lead the way towards an alternative perspective on handling disruptions. Firstly, it does not necessarily predispose that incidents are known or predictable. Moreover, it conceptualises that a system will undergo a number of phases during the draw-down and draw-up cycle following an adverse event, that each can be assessed and exploited for system improvements. This resilience perspective has been the premise of this thesis and drove development of computational models for the assessment of possible disruption management and decision-making strategies that remedy the impact of adverse events in transit systems. By taking resilience assessment as a key requirement, computational models need to capture the complete and dynamic draw-down and draw-up cycle during a disruption. At the same time, this thesis emphasizes that system performance ought to be, at least partly, expressed in terms of the inherent level-of-service that a transit system provides to passengers. Any evaluation or optimisation of system planning and operational rescheduling measures thus requires an explicit treatment of passengers and their interaction with the transit system supply. In addition, uncertainties related to variability of demand and supply as well as limited or lack of knowledge about current and future system conditions are prevalent. On the one hand, this means that models need to be able to capture these uncertainties. On the other hand, planning strategies and operational measures need to account and exploit these uncertainties to better cope whenever disruptions impinge on the network. In order to tackle the aforementioned challenges, this thesis starts by analyzing and reproducing the user demand patterns via the development of a ...
    Schlagwörter Transport Simulation ; Agent-based modelling ; Disruption modeling ; Resilience assessment ; info:eu-repo/classification/ddc/620 ; info:eu-repo/classification/ddc/004 ; info:eu-repo/classification/ddc/600 ; Engineering & allied operations ; Data processing ; computer science ; Technology (applied sciences)
    Thema/Rubrik (Code) 380
    Sprache Englisch
    Verlag ETH Zurich
    Erscheinungsland ch
    Dokumenttyp Dissertation / Habilitation ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  2. Artikel: Messen von Ankopplungskräften zur Beurteilung der Vibrationsübertragung auf die Hände - Preiswerte Alternative zu konventioneller Messtechnik

    Steffen, O. / Kaulbars, U.

    Lärmbekämpfung

    2017  Band 12, Heft 2, Seite(n) 69

    Sprache Deutsch
    Dokumenttyp Artikel
    ZDB-ID 2251449-1
    ISSN 1863-4672
    Datenquelle Current Contents Medizin

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  3. Artikel ; Online: Effects of stressor characteristics on early warning signs of critical transitions and "critical coupling" in complex dynamical systems.

    Blume, Steffen O P / Sansavini, Giovanni

    Chaos (Woodbury, N.Y.)

    2017  Band 27, Heft 12, Seite(n) 121101

    Abstract: Complex dynamical systems face abrupt transitions into unstable and catastrophic regimes. These critical transitions are triggered by gradual modifications in stressors, which push the dynamical system towards unstable regimes. Bifurcation analysis can ... ...

    Abstract Complex dynamical systems face abrupt transitions into unstable and catastrophic regimes. These critical transitions are triggered by gradual modifications in stressors, which push the dynamical system towards unstable regimes. Bifurcation analysis can characterize such critical thresholds, beyond which systems become unstable. Moreover, the stochasticity of the external stressors causes small-scale fluctuations in the system response. In some systems, the decomposition of these signal fluctuations into precursor signals can reveal early warning signs prior to the critical transition. Here, we present a dynamical analysis of a power system subjected to an increasing load level and small-scale stochastic load perturbations. We show that the auto- and cross-correlations of bus voltage magnitudes increase, leading up to a Hopf bifurcation point, and further grow until the system collapses. This evidences a gradual transition into a state of "critical coupling," which is complementary to the established concept of "critical slowing down." Furthermore, we analyze the effects of the type of load perturbation and load characteristics on early warning signs and find that gradient changes in the autocorrelation provide early warning signs of the imminent critical transition under white-noise but not for auto-correlated load perturbations. Furthermore, the cross-correlation between all voltage magnitude pairs generally increases prior to and beyond the Hopf bifurcation point, indicating "critical coupling," but cannot provide early warning indications. Finally, we show that the established early warning indicators are oblivious to limit-induced bifurcations and, in the case of the power system model considered here, only react to an approaching Hopf bifurcation.
    Sprache Englisch
    Erscheinungsdatum 2017-12
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 1472677-4
    ISSN 1089-7682 ; 1054-1500
    ISSN (online) 1089-7682
    ISSN 1054-1500
    DOI 10.1063/1.5008315
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  4. Buch ; Dissertation / Habilitation: Computersonographische Bestimmung der Höhe des Conus medullaris, des Durchmessers des Rückenmarks und des Wirbelkanals bei reifen und unreifen Neugeborenen

    Pickel, Steffen Oliver

    1994  

    Verfasserangabe vorgelegt von Steffen Oliver Pickel
    Sprache Deutsch
    Umfang 69 Bl. : Ill., graph. Darst.
    Ausgabenhinweis [Mikrofiche-Ausg.]
    Dokumenttyp Buch ; Dissertation / Habilitation
    Dissertation / Habilitation Saarbrücken, Univ., Diss., 1994
    Anmerkung Mikrofiche-Ausg.: 1 Mikrofiche : 24x
    HBZ-ID HT006683928
    Datenquelle Katalog ZB MED Medizin, Gesundheit

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  5. Artikel: Risiko for maeslingeepidemi i Danmark.

    Glismann, Steffen O

    Ugeskrift for laeger

    2002  Band 164, Heft 49, Seite(n) 5745–5747

    Titelübersetzung Risk of measles epidemic in Denmark.
    Mesh-Begriff(e) Child ; Child, Preschool ; Denmark/epidemiology ; Disease Outbreaks ; Humans ; Incidence ; Infant ; Measles/epidemiology ; Measles/prevention & control ; Measles-Mumps-Rubella Vaccine/administration & dosage ; Risk Factors
    Chemische Substanzen Measles-Mumps-Rubella Vaccine
    Sprache Dänisch
    Erscheinungsdatum 2002-12-02
    Erscheinungsland Denmark
    Dokumenttyp Journal Article
    ZDB-ID 124102-3
    ISSN 1603-6824 ; 0041-5782
    ISSN (online) 1603-6824
    ISSN 0041-5782
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  6. Artikel ; Online: First Measurement Using Elliptically Polarized Photons of the Double-Polarization Observable E for γp→pπ^{0} and γp→nπ^{+}.

    Afzal, F / Spieker, K / Hurck, P / Abt, S / Achenbach, P / Adlarson, P / Ahmed, Z / Akondi, C S / Annand, J R M / Arends, H J / Bashkanov, M / Beck, R / Biroth, M / Borisov, N / Braghieri, A / Briscoe, W J / Cividini, F / Collicott, C / Costanza, S /
    Denig, A / Dieterle, M / Downie, E J / Drexler, P / Fegan, S / Gardner, S / Ghosal, D / Glazier, D I / Gorodnov, I / Gradl, W / Gurevich, D / Heijkenskjöld, L / Hornidge, D / Huber, G M / Kashevarov, V L / Kay, S J D / Korolija, M / Krusche, B / Lazarev, A / Livingston, K / Lutterer, S / MacGregor, I J D / Macrae, R G / Manley, D M / Martel, P P / Miskimen, R / Mocanu, M / Mornacchi, E / Mullen, C / Neganov, A / Neiser, A / Oberle, M / Ostrick, M / Otte, P B / Paudyal, D / Pedroni, P / Powell, A / Reicherz, G / Rostomyan, T / Sfienti, C / Sokhoyan, V / Steffen, O / Strakovsky, I I / Strub, T / Supek, I / Thiel, A / Thiel, M / Thomas, A / Usov, Yu A / Wagner, S / Walford, N K / Watts, D P / Werthmüller, D / Wettig, J / Witthauer, L / Wolfes, M / Zachariou, N

    Physical review letters

    2024  Band 132, Heft 12, Seite(n) 121902

    Abstract: We report the measurement of the helicity asymmetry E for the pπ^{0} and nπ^{+} final states using, for the first time, an elliptically polarized photon beam in combination with a longitudinally polarized target at the Crystal Ball experiment at MAMI. ... ...

    Abstract We report the measurement of the helicity asymmetry E for the pπ^{0} and nπ^{+} final states using, for the first time, an elliptically polarized photon beam in combination with a longitudinally polarized target at the Crystal Ball experiment at MAMI. The results agree very well with data that were taken with a circularly polarized photon beam, showing that it is possible to simultaneously measure polarization observables that require linearly (e.g., G) and circularly polarized photons (e.g., E) and a longitudinally polarized target. The new data cover a photon energy range 270-1400 MeV for the pπ^{0} final state (230-842 MeV for the nπ^{+} final state) and the full range of pion polar angles, θ, providing the most precise measurement of the observable E. A moment analysis gives a clear observation of the pη cusp in the pπ^{0} final state.
    Sprache Englisch
    Erscheinungsdatum 2024-04-05
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.132.121902
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  7. Buch ; Dissertation / Habilitation: Die Einführung des Kapitalismus in Rußland

    Steffen, Olaf

    Ursachen, Programme und Krise der Transformationspolitik

    (Osteuropa ; 16)

    1997  

    Titelvarianten Der sowjetisch-russische Übergang zur Marktwirtschaft
    Verfasserangabe Olaf Steffen
    Serientitel Osteuropa ; 16
    Schlagwörter Marktwirtschaft ; Wirtschaftsreform ; Russland
    Sprache Deutsch
    Umfang 828 S, 21 cm
    Verlag Lit
    Erscheinungsort Hamburg
    Dokumenttyp Buch ; Dissertation / Habilitation
    Dissertation / Habilitation Univ., FB Phil. und Sozialwiss., Diss. u.d.T.: Steffen, Olaf: Der sowjetisch-russische Übergang zur Marktwirtschaft--Hamburg, 1996
    ISBN 3825832902 ; 9783825832902
    Datenquelle Ehemaliges Sondersammelgebiet Küsten- und Hochseefischerei

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  8. Artikel: Assessment of maxillary and infraorbital nerve blockade for rhinoscopy in sevoflurane anesthetized dogs

    Cremer, Jeannette / Steffen O Sum / Christina Braun / Juliana Figueiredo / Carolina Rodriguez‐Guarin

    Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia Veterinary anaesthesia and analgesia. 2013 July, v. 40, no. 4

    2013  

    Abstract: To investigate the efficacy of maxillary and infraorbital nerve blocks for prevention of cardiovascular and qualitative responses to rhinoscopy, as well as response to skin clamping after assigned nerve block placement.Randomized, blinded, placebo‐ ... ...

    Abstract To investigate the efficacy of maxillary and infraorbital nerve blocks for prevention of cardiovascular and qualitative responses to rhinoscopy, as well as response to skin clamping after assigned nerve block placement.Randomized, blinded, placebo‐controlled cross‐over experimental study.Eight random‐source mixed breed dogs > 1 year old and weighing between 13 and 22 kg.Within three anesthetic episodes, separated by at least 3 days, dogs were assigned to receive either 1 mL lidocaine 2% maxillary nerve block (ML); 0.5 mL lidocaine 2% infraorbital nerve block (IOL); or equal amounts of saline for maxillary or infraorbital nerve block combined as control treatment (S). Monitoring included temperature, respiratory rate, end‐tidal CO2, ECG, heart rate (HR), systolic, diastolic and mean arterial pressure (SAP, DAP, MAP). Posterior (pR) and anterior rhinoscopies (aR) were performed and scored. Differences from baseline for outcome parameters HR, SAP, DAP, MAP were analyzed using repeated‐measures anova, and results reported as mean ± SD. Binary scores for rhinoscopy were analyzed using logistic regression, and odds ratio was reported.Changes from baseline for HR and SAP were significant for all treatments, besides ML for pR. Difference in changes from baseline among treatments was statistically significant for HR during pR with ML < S, and for SAP, DAP and MAP in right and left aR with ML < S and IOL > ML, except for DAP in left aR with only IOL > ML. Analysis of the binary score showed that the probability of a response for S and IOL treatments was nearly triple that of the ML treatment. None of the dogs, regardless of the treatments applied, responded to skin clamping.Cardiovascular parameters do not seem to reflect the occurrence of adverse reactions during rhinoscopy. The maxillary nerve block is superior to the infraorbital nerve block, as applied in this study, in preventing adverse reactions during posterior rhinoscopy.
    Schlagwörter adverse effects ; carbon dioxide ; dogs ; heart rate ; lidocaine ; mixed breeds ; monitoring ; nerve tissue ; odds ratio ; regression analysis ; respiratory rate ; rhinoscopy ; sevoflurane ; temperature
    Sprache Englisch
    Erscheinungsverlauf 2013-07
    Umfang p. 432-439.
    Erscheinungsort Elsevier Ltd
    Dokumenttyp Artikel
    ZDB-ID 2020582-X
    ISSN 1467-2995 ; 1467-2987
    ISSN (online) 1467-2995
    ISSN 1467-2987
    DOI 10.1111/vaa.12032
    Datenquelle NAL Katalog (AGRICOLA)

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  9. Buch ; Dissertation / Habilitation: Die Einführung des Kapitalismus in Rußland

    Steffen, Olaf

    Ursachen, Programme und Krise der Transformationspolitik

    (Osteuropa ; 16)

    1997  

    Verfasserangabe Olaf Steffen
    Serientitel Osteuropa ; 16
    Schlagwörter Systemtransformation ; Neue politische Ökonomie ; Wirtschaftskrise ; Inflationsbekämpfung ; Finanzpolitik ; Öffentliche Schulden ; Privatisierung ; Russland ; 18*28*38*48*58*68*78*87*86*85*84*83*82*81
    Sprache Deutsch
    Umfang 828 S
    Dokumenttyp Buch ; Dissertation / Habilitation
    Dissertation / Habilitation Zugl.: Hamburg, Univ., Diss., 1996
    Anmerkung Literaturverz. S. 781 - 828
    ISBN 3825832902 ; 9783825832902
    Datenquelle ECONomics Information System

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  10. Buch ; Dissertation / Habilitation: Die Einführung des Kapitalismus in Rußland

    Steffen, Olaf

    Ursachen, Programme und Krise der Transformationspolitik

    (Osteuropa ; 16)

    1997  

    Titelvarianten Der sowjetisch-russische Übergang zur Marktwirtschaft
    Verfasserangabe Olaf Steffen
    Serientitel Osteuropa ; 16
    Schlagwörter Marktwirtschaft ; Wirtschaftsreform ; Russland
    Sprache Deutsch
    Umfang 828 S, 21 cm
    Dokumenttyp Buch ; Dissertation / Habilitation
    Dissertation / Habilitation Zugl.: Hamburg, Univ., FB Phil. und Sozialwiss., Diss., 1996 u.d.T.: Steffen, Olaf: Der sowjetisch-russische Übergang zur Marktwirtschaft
    ISBN 3825832902 ; 9783825832902
    Datenquelle ECONomics Information System

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