@article{AyzelHeistermannWinterrath2019,
  author    = {Ayzel, Georgy and Heistermann, Maik and Winterrath, Tanja},
  title     = {Optical flow models as an open benchmark for radar-based precipitation nowcasting (rainymotion v0.1)},
  series = {Geoscientific model development},
  journal   = {Geoscientific model development},
  number    = {12},
  publisher = {Copernicus Publications},
  address   = {G{\"o}ttingen},
  issn      = {1991-9603},
  doi       = {10.5194/gmd-12-1387-2019},
  pages     = {1387 -- 1402},
  year      = {2019},
  abstract  = {Quantitative precipitation nowcasting (QPN) has become an essential technique in various application contexts, such as early warning or urban sewage control. A common heuristic prediction approach is to track the motion of precipitation features from a sequence of weather radar images and then to displace the precipitation field to the imminent future (minutes to hours) based on that motion, assuming that the intensity of the features remains constant ("Lagrangian persistence"). In that context, "optical flow" has become one of the most popular tracking techniques. Yet the present landscape of computational QPN models still struggles with producing open software implementations. Focusing on this gap, we have developed and extensively benchmarked a stack of models based on different optical flow algorithms for the tracking step and a set of parsimonious extrapolation procedures based on image warping and advection. We demonstrate that these models provide skillful predictions comparable with or even superior to state-of-the-art operational software. Our software library ("rainymotion") for precipitation nowcasting is written in the Python programming language and openly available at GitHub (https://github.com/hydrogo/rainymotion, Ayzel et al., 2019). That way, the library may serve as a tool for providing fast, free, and transparent solutions that could serve as a benchmark for further model development and hypothesis testing - a benchmark that is far more advanced than the conventional benchmark of Eulerian persistence commonly used in QPN verification experiments.},
  language  = {en}
}
@misc{AyzelHeistermannWinterrath2019,
  author    = {Ayzel, Georgy and Heistermann, Maik and Winterrath, Tanja},
  title     = {Optical flow models as an open benchmark for radar-based precipitation nowcasting (rainymotion v0.1)},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {709},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-42933},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-429333},
  pages     = {16},
  year      = {2019},
  abstract  = {Quantitative precipitation nowcasting (QPN) has become an essential technique in various application contexts, such as early warning or urban sewage control. A common heuristic prediction approach is to track the motion of precipitation features from a sequence of weather radar images and then to displace the precipitation field to the imminent future (minutes to hours) based on that motion, assuming that the intensity of the features remains constant ("Lagrangian persistence"). In that context, "optical flow" has become one of the most popular tracking techniques. Yet the present landscape of computational QPN models still struggles with producing open software implementations. Focusing on this gap, we have developed and extensively benchmarked a stack of models based on different optical flow algorithms for the tracking step and a set of parsimonious extrapolation procedures based on image warping and advection. We demonstrate that these models provide skillful predictions comparable with or even superior to state-of-the-art operational software. Our software library ("rainymotion") for precipitation nowcasting is written in the Python programming language and openly available at GitHub (https://github.com/hydrogo/rainymotion, Ayzel et al., 2019). That way, the library may serve as a tool for providing fast, free, and transparent solutions that could serve as a benchmark for further model development and hypothesis testing - a benchmark that is far more advanced than the conventional benchmark of Eulerian persistence commonly used in QPN verification experiments.},
  language  = {en}
}
@misc{DuyHeidbuechelMeyeretal.2018,
  author    = {Duy, Nguyen Le and Heidb{\"u}chel, Ingo and Meyer, Hanno and Merz, Bruno and Apel, Heiko},
  title     = {What controls the stable isotope composition of precipitation in the Mekong Delta?},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {927},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-44574},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-445743},
  pages     = {1239 -- 1262},
  year      = {2018},
  abstract  = {This study analyzes the influence of local and regional climatic factors on the stable isotopic composition of rainfall in the Vietnamese Mekong Delta (VMD) as part of the Asian monsoon region. It is based on 1.5 years of weekly rainfall samples. In the first step, the isotopic composition of the samples is analyzed by local meteoric water lines (LMWLs) and single-factor linear correlations. Additionally, the contribution of several regional and local factors is quantified by multiple linear regression (MLR) of all possible factor combinations and by relative importance analysis. This approach is novel for the interpretation of isotopic records and enables an objective quantification of the explained variance in isotopic records for individual factors. In this study, the local factors are extracted from local climate records, while the regional factors are derived from atmospheric backward trajectories of water particles. The regional factors, i.e., precipitation, temperature, relative humidity and the length of backward trajectories, are combined with equivalent local climatic parameters to explain the response variables delta O-18, delta H-2, and d-excess of precipitation at the station of measurement. The results indicate that (i) MLR can better explain the isotopic variation in precipitation (R-2 = 0.8) compared to single-factor linear regression (R-2 = 0.3); (ii) the isotopic variation in precipitation is controlled dominantly by regional moisture regimes (similar to 70 \%) compared to local climatic conditions (similar to 30 \%); (iii) the most important climatic parameter during the rainy season is the precipitation amount along the trajectories of air mass movement; (iv) the influence of local precipitation amount and temperature is not sig-nificant during the rainy season, unlike the regional precipitation amount effect; (v) secondary fractionation processes (e.g., sub-cloud evaporation) can be identified through the d-excess and take place mainly in the dry season, either locally for delta O-18 and delta H-2, or along the air mass trajectories for d-excess. The analysis shows that regional and local factors vary in importance over the seasons and that the source regions and transport pathways, and particularly the climatic conditions along the pathways, have a large influence on the isotopic composition of rainfall. Although the general results have been reported qualitatively in previous studies (proving the validity of the approach), the proposed method provides quantitative estimates of the controlling factors, both for the whole data set and for distinct seasons. Therefore, it is argued that the approach constitutes an advancement in the statistical analysis of isotopic records in rainfall that can supplement or precede more complex studies utilizing atmospheric models. Due to its relative simplicity, the method can be easily transferred to other regions, or extended with other factors. The results illustrate that the interpretation of the isotopic composition of precipitation as a recorder of local climatic conditions, as for example performed for paleorecords of water isotopes, may not be adequate in the southern part of the Indochinese Peninsula, and likely neither in other regions affected by monsoon processes. However, the presented approach could open a pathway towards better and seasonally differentiated reconstruction of paleoclimates based on isotopic records.},
  language  = {en}
}
@misc{LoritzHasslerJackischetal.2017,
  author    = {Loritz, Ralf and Hassler, Sibylle K. and Jackisch, Conrad and Allroggen, Niklas and van Schaik, Loes and Wienh{\"o}fer, Jan and Zehe, Erwin},
  title     = {Picturing and modeling catchments by representative hillslopes},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe},
  number    = {635},
  doi       = {10.25932/publishup-41908},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-419082},
  pages     = {1225 -- 1249},
  year      = {2017},
  abstract  = {This study explores the suitability of a single hillslope as a parsimonious representation of a catchment in a physically based model. We test this hypothesis by picturing two distinctly different catchments in perceptual models and translating these pictures into parametric setups of 2-D physically based hillslope models. The model parametrizations are based on a comprehensive field data set, expert knowledge and process-based reasoning. Evaluation against streamflow data highlights that both models predicted the annual pattern of streamflow generation as well as the hydrographs acceptably. However, a look beyond performance measures revealed deficiencies in streamflow simulations during the summer season and during individual rainfall-runoff events as well as a mismatch between observed and simulated soil water dynamics. Some of these shortcomings can be related to our perception of the systems and to the chosen hydrological model, while others point to limitations of the representative hillslope concept itself. Nevertheless, our results confirm that representative hillslope models are a suitable tool to assess the importance of different data sources as well as to challenge our perception of the dominant hydrological processes we want to represent therein. Consequently, these models are a promising step forward in the search for the optimal representation of catchments in physically based models.},
  language  = {en}
}
@misc{GuentnerReichMikolajetal.2017,
  author    = {G{\"u}ntner, Andreas and Reich, Marvin and Mikolaj, Michal and Creutzfeldt, Benjamin and Schroeder, Stephan and Wziontek, Hartmut},
  title     = {Landscape-scale water balance monitoring with an iGrav superconducting gravimeter in a field enclosure},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {663},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-41910},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-419105},
  pages     = {16},
  year      = {2017},
  abstract  = {In spite of the fundamental role of the landscape water balance for the Earth's water and energy cycles, monitoring the water balance and its components beyond the point scale is notoriously difficult due to the multitude of flow and storage processes and their spatial heterogeneity. Here, we present the first field deployment of an iGrav superconducting gravimeter (SG) in a minimized enclosure for long-term integrative monitoring of water storage changes. Results of the field SG on a grassland site under wet-temperate climate conditions were compared to data provided by a nearby SG located in the controlled environment of an observatory building. The field system proves to provide gravity time series that are similarly precise as those of the observatory SG. At the same time, the field SG is more sensitive to hydrological variations than the observatory SG. We demonstrate that the gravity variations observed by the field setup are almost independent of the depth below the terrain surface where water storage changes occur (contrary to SGs in buildings), and thus the field SG system directly observes the total water storage change, i.e., the water balance, in its surroundings in an integrative way. We provide a framework to single out the water balance components actual evapotranspiration and lateral subsurface discharge from the gravity time series on annual to daily timescales. With about 99 and 85\% of the gravity signal due to local water storage changes originating within a radius of 4000 and 200m around the instrument, respectively, this setup paves the road towards gravimetry as a continuous hydrological field-monitoring technique at the landscape scale.},
  language  = {en}
}
@misc{LangerwischWalzRammigetal.2016,
  author    = {Langerwisch, F. and Walz, Ariane and Rammig, A. and Tietjen, B. and Thonicke, Kirsten and Cramer, Wolfgang},
  title     = {Climate change increases riverine carbon outgassing, while export to the ocean remains uncertain},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {526},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-41017},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-410177},
  pages     = {24},
  year      = {2016},
  abstract  = {Any regular interaction of land and river during flooding affects carbon pools within the terrestrial system, riverine carbon and carbon exported from the system. In the Amazon basin carbon fluxes are considerably influenced by annual flooding, during which terrigenous organic material is imported to the river. The Amazon basin therefore represents an excellent example of a tightly coupled terrestrial-riverine system. The processes of generation, conversion and transport of organic carbon in such a coupled terrigenous-riverine system strongly interact and are climate-sensitive, yet their functioning is rarely considered in Earth system models and their response to climate change is still largely unknown. To quantify regional and global carbon budgets and climate change effects on carbon pools and carbon fluxes, it is important to account for the coupling between the land, the river, the ocean and the atmosphere. We developed the RIVerine Carbon Model (RivCM), which is directly coupled to the well-established dynamic vegetation and hydrology model LPJmL, in order to account for this large-scale coupling. We evaluate RivCM with observational data and show that some of the values are reproduced quite well by the model, while we see large deviations for other variables. This is mainly caused by some simplifications we assumed. Our evaluation shows that it is possible to reproduce large-scale carbon transport across a river system but that this involves large uncertainties. Acknowledging these uncertainties, we estimate the potential changes in riverine carbon by applying RivCM for climate forcing from five climate models and three CO2 emission scenarios (Special Report on Emissions Scenarios, SRES). We find that climate change causes a doubling of riverine organic carbon in the southern and western basin while reducing it by 20\% in the eastern and northern parts. In contrast, the amount of riverine inorganic carbon shows a 2- to 3-fold increase in the entire basin, independent of the SRES scenario. The export of carbon to the atmosphere increases as well, with an average of about 30 \%. In contrast, changes in future export of organic carbon to the Atlantic Ocean depend on the SRES scenario and are projected to either decrease by about 8.9\% (SRES A1B) or increase by about 9.1\% (SRES A2). Such changes in the terrigenous-riverine system could have local and regional impacts on the carbon budget of the whole Amazon basin and parts of the Atlantic Ocean. Changes in riverine carbon could lead to a shift in the riverine nutrient supply and pH, while changes in the exported carbon to the ocean lead to changes in the supply of organic material that acts as a food source in the Atlantic. On larger scales the increased outgassing of CO2 could turn the Amazon basin from a sink of carbon to a considerable source. Therefore, we propose that the coupling of terrestrial and riverine carbon budgets should be included in subsequent analysis of the future regional carbon budget.},
  language  = {en}
}
@misc{ZieglerHeidbachReineckeretal.2016,
  author    = {Ziegler, Moritz O. and Heidbach, Oliver and Reinecker, John and Przybycin, Anna M. and Scheck-Wenderoth, Magdalena},
  title     = {A multi-stage 3-D stress field modelling approach exemplified in the Bavarian Molasse Basin},
  series = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  number    = {556},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-40980},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-409806},
  pages     = {18},
  year      = {2016},
  abstract  = {The knowledge of the contemporary in situ stress state is a key issue for safe and sustainable subsurface engineering. However, information on the orientation and magnitudes of the stress state is limited and often not available for the areas of interest. Therefore 3-D geomechanical-numerical modelling is used to estimate the in situ stress state and the distance of faults from failure for application in subsurface engineering. The main challenge in this approach is to bridge the gap in scale between the widely scattered data used for calibration of the model and the high resolution in the target area required for the application. We present a multi-stage 3-D geomechanical-numerical approach which provides a state-of-the-art model of the stress field for a reservoir-scale area from widely scattered data records. Therefore, we first use a large-scale regional model which is calibrated by available stress data and provides the full 3-D stress tensor at discrete points in the entire model volume. The modelled stress state is used subsequently for the calibration of a smaller-scale model located within the large-scale model in an area without any observed stress data records. We exemplify this approach with two-stages for the area around Munich in the German Molasse Basin. As an example of application, we estimate the scalar values for slip tendency and fracture potential from the model results as measures for the criticality of fault reactivation in the reservoir-scale model. The modelling results show that variations due to uncertainties in the input data are mainly introduced by the uncertain material properties and missing S-Hmax magnitude estimates needed for a more reliable model calibration. This leads to the conclusion that at this stage the model's reliability depends only on the amount and quality of available stress information rather than on the modelling technique itself or on local details of the model geometry. Any improvements in modelling and increases in model reliability can only be achieved using more high-quality data for calibration.},
  language  = {en}
}
@misc{FrielerLevermannElliottetal.2015,
  author    = {Frieler, Katja and Levermann, Anders and Elliott, J. and Heinke, J. and Arneth, A. and Bierkens, M. F. P. and Ciais, Philippe and Clark, D. B. and Deryng, D. and Doell, P. and Falloon, P. and Fekete, B. and Folberth, Christian and Friend, A. D. and Gellhorn, C. and Gosling, S. N. and Haddeland, I. and Khabarov, N. and Lomas, M. and Masaki, Y. and Nishina, K. and Neumann, K. and Oki, T. and Pavlick, R. and Ruane, A. C. and Schmid, E. and Schmitz, C. and Stacke, T. and Stehfest, E. and Tang, Q. and Wisser, D. and Huber, V. and Piontek, Franziska and Warszawski, L. and Schewe, Jacob and Lotze-Campen, Hermann and Schellnhuber, Hans Joachim},
  title     = {A framework for the cross-sectoral integration of multi-model impact projections},
  series = {Earth system dynamics},
  journal   = {Earth system dynamics},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-407968},
  pages     = {14},
  year      = {2015},
  abstract  = {Climate change and its impacts already pose considerable challenges for societies that will further increase with global warming (IPCC, 2014a, b). Uncertainties of the climatic response to greenhouse gas emissions include the potential passing of large-scale tipping points (e.g. Lenton et al., 2008; Levermann et al., 2012; Schellnhuber, 2010) and changes in extreme meteorological events (Field et al., 2012) with complex impacts on societies (Hallegatte et al., 2013). Thus climate change mitigation is considered a necessary societal response for avoiding uncontrollable impacts (Conference of the Parties, 2010). On the other hand, large-scale climate change mitigation itself implies fundamental changes in, for example, the global energy system. The associated challenges come on top of others that derive from equally important ethical imperatives like the fulfilment of increasing food demand that may draw on the same resources. For example, ensuring food security for a growing population may require an expansion of cropland, thereby reducing natural carbon sinks or the area available for bio-energy production. So far, available studies addressing this problem have relied on individual impact models, ignoring uncertainty in crop model and biome model projections. Here, we propose a probabilistic decision framework that allows for an evaluation of agricultural management and mitigation options in a multi-impact-model setting. Based on simulations generated within the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), we outline how cross-sectorally consistent multi-model impact simulations could be used to generate the information required for robust decision making. Using an illustrative future land use pattern, we discuss the trade-off between potential gains in crop production and associated losses in natural carbon sinks in the new multiple crop-and biome-model setting. In addition, crop and water model simulations are combined to explore irrigation increases as one possible measure of agricultural intensification that could limit the expansion of cropland required in response to climate change and growing food demand. This example shows that current impact model uncertainties pose an important challenge to long-term mitigation planning and must not be ignored in long-term strategic decision making.},
  language  = {en}
}
@misc{ViouxTaubert2014,
  author    = {Vioux, Andr{\´e} and Taubert, Andreas},
  title     = {Ionic liquids 2014 and selected papers from ILMAT 2013},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {1055},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-47506},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-475062},
  pages     = {6},
  year      = {2014},
  language  = {en}
}
@misc{ThielZehbeRoeseretal.2013,
  author    = {Thiel, Kerstin and Zehbe, Rolf and Roeser, Jer{\^o}m{\´e} and Strauch, Peter and Enthaler, Stephan and Thomas, Arne},
  title     = {A polymer analogous reaction for the formation of imidazolium and NHC based porous polymer networks},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95118},
  pages     = {1848 -- 1856},
  year      = {2013},
  abstract  = {A polymer analogous reaction was carried out to generate a porous polymeric network with N-heterocyclic carbenes (NHC) in the polymer backbone. Using a stepwise approach, first a polyimine network is formed by polymerization of the tetrafunctional amine tetrakis(4-aminophenyl)methane. This polyimine network is converted in the second step into polyimidazolium chloride and finally to a polyNHC network. Furthermore a porous Cu(II)-coordinated polyNHC network can be generated. Supercritical drying generates polymer networks with high permanent surface areas and porosities which can be applied for different catalytic reactions. The catalytic properties were demonstrated for example in the activation of CO2 or in the deoxygenation of sulfoxides to the corresponding sulfides.},
  language  = {en}
}
@phdthesis{Gause2011,
  author    = {Gause, Clemens},
  title     = {Das System der Strategie : ein Vergleich zwischen Strategien biologischer Systeme und milit{\"a}rischen Strategien ; eine Modellentwicklung},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-50068},
  school      = {Universit{\"a}t Potsdam},
  year      = {2011},
  abstract  = {Das vorliegende Buch vergleicht Strategien biologischer Systeme mit milit{\"a}rischen Strategien. Die zentrale Fragestellung ist dabei darauf gerichtet, ob es neben systemischen Gemeinsamkeiten auch gemeinsame oder {\"a}hnliche Strukturmuster und {\"a}hnliche Prozessabl{\"a}ufe beispielsweise sowohl im biologischen Abwehrmechanismus des Immunsystems und bei Insektenstaaten als auch bei Prozessen im Milit{\"a}r gibt. Vor diesem Hintergrund klaffen in der Theorie der Strategie, speziell in den Milit{\"a}rwissenschaften L{\"u}cken, denn der Systemansatz wird nicht konsequent beachtet, wie in diesem Buch mehrfach nachgewiesen ist. Von einem allgemeinen Verst{\"a}ndnis der Strategie als bewusstem planerischem Vorgehen ist Abstand zu nehmen. Ausgehend von der Methode der Analogie und des Vergleichs wird im theoretischen Teil dieses Buches die Allgemeine Systemtheorie erl{\"a}utert. Dabei werden der Begriff der Strategie ebenso wie die Begriffe Struktur und Prozess und Ans{\"a}tze aus der Kriegsphilosophie von Clausewitz untersucht. Den Ausgangspunkt und schließlich auch wieder den Endpunkt der {\"U}berlegungen bilden neben dem notwendigen weiten Verst{\"a}ndnis von Strategie, vor allem der Begriff der Organisation, ihrer Umwelt und der in diesem Zusammenhang bestehenden Wechselwirkung. Sowohl die Wechselwirkung von Umwelt und System als auch ihre Abh{\"a}ngigkeit durch strukturelle Kopplung werden beschrieben. Das Zusammenspiel und die daraus entstehende Komplexit{\"a}t der f{\"u}nf Komponenten der Wahrnehmung, der Information und der F{\"u}hrung im Zusammenhang der Komponenten von Raum und Zeit in einem sozialen System lassen die klassische Ziel-Mittel-Zweck-Beziehung Clausewitz´scher Strategiedefinition verk{\"u}rzt erscheinen. Anhand eines kurzen Rekurses der Methoden der Sozialen Netzwerkanalyse (SNA) wird der breite und tiefgehende Analyserahmen der Messung und Transparenzerreichung in Organisationen vorgestellt. Die SNA wird als Auspr{\"a}gung der Netzwerk- und Graphentheorie, in die Allgemeine Systemtheorie integriert. Sie bildet eine zukunftsweisende Methode der Untersuchung von Netzwerken wie etwa dem Internet (Facebook, Xing etc.). Der aufgezeigte Theorierahmen bildet dabei zugleich eine Methode f{\"u}r den Systemvergleich und kann als Vorgehensmodell k{\"u}nftiger Strategieentwicklung genutzt werden. Der anschließende Systemvergleich wird mit mehreren Beispielen durchgef{\"u}hrt. Ausgehend von der Zelle als Grundeinheit werden Strukturen und Prozesse des Immunsystems mit solchen in milit{\"a}rischen Strukturen, weil sie im Lauf der Evolution enorme Leistungen in Reaktion, Anpassung und Optimierung vollbracht haben. Der Vergleich geht der Frage nach, ob in diesen Bereichen der Strategie und Organisation systemische Grundregeln existieren. Das Beispiel der Wechselwirkung zwischen Parasit und Wirt zeigt, dass jeder Fortschritt und Sieg angesichts der Systemeinbettung von Strategie nur relativ wirken kann. Die Analogie zwischen Viren und Bakterien sowie die Entwicklung des Begriffs der sozialen Mimikry f{\"u}hren zu einem erweiterten Verst{\"a}ndnis der Strategie von Terroristen in sozialen Systemen. Verdeutlicht wird das Grundschema des T{\"a}uschens und Eindringens in Systeme sowie die Beeinflussung und Umsteuerung von Prozessen und Strukturen in einem System durch Kommunikation und Implementation von Codes. Am Beispiel des Immunsystems und der Bildung verschiedener Kommunikations- und Steuerungsmechanismen von Zellsystemen sowie Beispielen von Schwarmbildung und der Organisation sozialer Insekten werden eine Vielzahl heuristischer Hinweise f{\"u}r neue Ans{\"a}tze f{\"u}r die Organisation von Streitkr{\"a}ften und ihrer Steuerung gefunden. Neben der Erarbeitung eines grundlegenden Strategiebegriffs anhand von Wahrnehmung und Selektion als Grundprozess der Erzeugung von Strategie wird eine differenzierte Betrachtung von Begriffen wie Redundanz und Robustheit sowie eine relativierende Sichtweise von Risiko, Gefahr und Schaden gewonnen. Der Vergleich mit dem Immunsystems zeigt einfache Beispiele der Informationsspeicherung und -{\"u}bertragung, die zudem Bypassf{\"a}higkeiten sowie dezentrale Eskalations- und Deeskalationsprinzipien veranschaulichen. Dies er{\"o}ffnet in Analogie dieser Prinzipien einen weiten Raum Sicherheitsarchitekturen zu {\"u}berdenken und neu zu strukturieren. Zudem kann die r{\"a}umliche Ausbreitung von Information und Kr{\"a}ften als ein gemeinsames Grundproblem der Entwicklung und Wirksamkeit von Strategien sowohl in der Natur, als auch im Milit{\"a}r identifiziert werden. Die Betrachtung zeigt zudem wie Zellen mit fehlgeleiteten Prozessen und Strukturen umgehen. Die Analogie deutet auf das Erfordernis einer Ver{\"a}nderung im Umgang mit Fehlern und ihrer R{\"u}ckf{\"u}hr- und Umkehrbarkeit im weitesten Sinne. Das Buch er{\"o}ffnet {\"u}berdies ein neues Verst{\"a}ndnis von Staat, Gewaltenteilung und Institutionen in einem sozialen System. Die Ergebnisse sind auch auf andere Forschungsbereiche, Organisationen und unterschiedlichste soziale Systeme {\"u}bertragbar. Es er{\"o}ffnet sich ein breites Anwendungsspektrum f{\"u}r k{\"u}nftige strategische Untersuchungen.},
  language  = {de}
}
@phdthesis{Topaj2001,
  author    = {Topaj, Dmitri},
  title     = {Synchronization transitions in complex systems},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-0000367},
  school      = {Universit{\"a}t Potsdam},
  year      = {2001},
  abstract  = {Gegenstand dieser Arbeit ist die Untersuchung generischer Synchronisierungsph{\"a}nomene in interagierenden komplexen Systemen. Diese Ph{\"a}nomene werden u.a. in gekoppelten deterministischen chaotischen Systemen beobachtet. Bei sehr schwachen Interaktionen zwischen individuellen Systemen kann ein {\"U}bergang zum schwach koh{\"a}renten Verhalten der Systeme stattfinden. In gekoppelten zeitkontinuierlichen chaotischen Systemen manifestiert sich dieser {\"U}bergang durch den Effekt der Phasensynchronisierung, in gekoppelten chaotischen zeitdiskreten Systemen durch den Effekt eines nichtverschwindenden makroskopischen Feldes. Der {\"U}bergang zur Koh{\"a}renz in einer Kette lokal gekoppelter Oszillatoren, beschrieben durch Phasengleichungen, wird im Bezug auf die Symmetrien des Systems untersucht. Es wird gezeigt, daß die durch die Symmetrien verursachte Reversibilit{\"a}t des Systems nichttriviale topologische Eigenschaften der Trajektorien bedingt, so daß das als dissipativ konstruierte System in einem ganzen Parameterbereich quasi-Hamiltonische Z{\"u}ge aufweist, d.h. das Phasenvolumen ist im Schnitt erhalten, und die Lyapunov-Exponenten sind paarweise symmetrisch. Der {\"U}bergang zur Koh{\"a}renz in einem Ensemble global gekoppelter chaotischer Abbildungen wird durch den Verlust der Stabilit{\"a}t des entkoppelten Zustandes beschrieben. Die entwickelte Methode besteht darin, die Selbstkonsistenz des makroskopischen Feldes aufzuheben, und das Ensemble in Analogie mit einem Verst{\"a}rkerschaltkreis mit R{\"u}ckkopplung durch eine komplexe lineare {\"U}bertragungssfunktion zu charakterisieren. Diese Theorie wird anschließend f{\"u}r einige theoretisch interessanten F{\"a}lle verallgemeinert.},
  language  = {en}
}