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A fine-grained slope that exhibits slow movement rates was investigated to understand how geohydrological processes contribute to a consecutive development of mass movements in the Vorarlberg Alps, Austria. For that purpose intensive hydrometeorological, hydrogeological and geotechnical observations as well as surveying of surface movement rates were conducted during 1998–2001. Subsurface water dynamics at the creeping slope turned out to be dominated by a three-dimensional pressure system. The pressure reaction is triggered by fast infiltration of surface water and subsequent lateral water flow in the south-western part of the hillslope. The related pressure signal was shown to propagate further downhill, causing fast reactions of the piezometric head at 5Ð5 m depth on a daily time scale. The observed pressure reactions might belong to a temporary hillslope water body that extends further downhill. The related buoyancy forces could be one of the driving forces for the mass movement. A physically based hydrological model was adopted to model simultaneously surface and subsurface water dynamics including evapotranspiration and runoff production. It was possible to reproduce surface runoff and observed pressure reactions in principle. However, as soil hydraulic functions were only estimated on pedotransfer functions, a quantitative comparison between observed and simulated subsurface dynamics is not feasible. Nevertheless, the results suggest that it is possible to reconstruct important spatial structures based on sparse observations in the field which allow reasonable simulations with a physically based hydrological model. Copyright 2005 John Wiley & Sons, Ltd. KEY WORDS rainfall-induced landslides; soil creep; hydrological modelling; Vorarlberg; Austria; pressure propagation
Predictability of hydrologic response at the plot and catchment scales: Role of initial conditions
(2004)
This paper examines the effect of uncertain initial soil moisture on hydrologic response at the plot scale (1 m2) and the catchment scale (3.6 km2) in the presence of threshold transitions between matrix and preferential flow. We adopt the concepts of microstates and macrostates from statistical mechanics. The microstates are the detailed patterns of initial soil moisture that are inherently unknown, while the macrostates are specified by the statistical distributions of initial soil moisture that can be derived from the measurements typically available in field experiments. We use a physically based model and ensure that it closely represents the processes in the Weiherbach catchment, Germany. We then use the model to generate hydrologic response to hypothetical irrigation events and rainfall events for multiple realizations of initial soil moisture microstates that are all consistent with the same macrostate. As the measures of uncertainty at the plot scale we use the coefficient of variation and the scaled range of simulated vertical bromide transport distances between realizations. At the catchment scale we use similar statistics derived from simulated flood peak discharges. The simulations indicate that at both scales the predictability depends on the average initial soil moisture state and is at a minimum around the soil moisture value where the transition from matrix to macropore flow occurs. The predictability increases with rainfall intensity. The predictability increases with scale with maximum absolute errors of 90 and 32% at the plot scale and the catchment scale, respectively. It is argued that even if we assume perfect knowledge on the processes, the level of detail with which one can measure the initial conditions along with the nonlinearity of the system will set limits to the repeatability of experiments and limits to the predictability of models at the plot and catchment scales.
How do children determine the syntactic category of novel words? In this article we present the results of 2 experiments that investigated whether German children between 12 and 16 months of age can use distributional knowledge that determiners precede nouns and subject pronouns precede verbs to syntactically categorize adjacent novel words. Evidence from the head-turn preference paradigm shows that, although 12- to 13-month-olds cannot do this, 14- to 16-month-olds are able to use a determiner to categorize a following novel word as a noun. In contrast, no categorization effect was found for a novel word following a subject pronoun. To understand this difference we analyzed adult child-directed speech. This analysis showed that there are in fact stronger co-occurrence relations between determiners and nouns than between subject pronouns and verbs. Thus, in German determiners may be more reliable cues to the syntactic category of an adjacent novel word than are subject pronouns. We propose that the capacity to syntactically categorize novel words, demonstrated here for the first time in children this young, mediates between the recognition of the specific morphosyntactic frame in which a novel word appears and the word-to-world mapping that is needed to build up a semantic representation for the novel word.
In the spring issue of WeltTrends, Gunther Hellmann (Johann-Wolfgang-Goethe- Universität Frankfurt a. M.) sparked a debate on Germany's foreign policy. He argued that Germany’s international behaviour is dominated by a Realpolitik policy generally referred to as "normalization". For Hellmann this transformation indicates "the deepest crisis of German foreign policy" ever. Hellmann proposes a rehabilitation of the tradition of the Bonner Republik and an active Idealpolitik. This summer issue of WeltTrends features eleven articles written in response to Hellmann by International Relations scholars. The debate focuses on analytical as well as normative aspects of current German foreign policy. The authors discuss the context of the European Common Foreign and Security Policy, the international system and the United Nations, historical aspects of German foreign policy and the German foreign policy discourse. While some contributors share Hellmann's idealist position, most challenge his plea from a more realist perspective. In the upcoming fall issue, this debate will be continued with contributions by German foreign policy makers. A final reply by Hellmann will complete the debate in the winter issue of WeltTrends. Contributions by: Franz Ansprenger, Stephan Böckenförde, Wilfried von Bredow, Sabine Busse, Edwina S. Campbell, Hartmut Elsenhans, Hans J. Gießmann, Werner Link, Carlo Masala, Hanns W. Maull, and Siegfried Schwarz.
In the spring issue of WeltTrends, Gunther Hellmann (Johann-Wolfgang-Goethe- Universität Frankfurt a. M.) sparked a debate on Germany’s foreign policy. He argued that Germany’s international behaviour is dominated by a Realpolitik policy generally referred to as "normalization". For Hellmann this transformation indicates "the deepest crisis of German foreign policy" ever. Hellmann proposes a rehabilitation of the tradition of the Bonner Republik and an active Idealpolitik. This summer issue of WeltTrends features eleven articles written in response to Hellmann by International Relations scholars. The debate focuses on analytical as well as normative aspects of current German foreign policy. The authors discuss the context of the European Common Foreign and Security Policy, the international system and the United Nations, historical aspects of German foreign policy and the German foreign policy discourse. While some contributors share Hellmann's idealist position, most challenge his plea from a more realist perspective. In the upcoming fall issue, this debate will be continued with contributions by German foreign policy makers. A final reply by Hellmann will complete the debate in the winter issue of WeltTrends. Contributions by: Franz Ansprenger, Stephan Böckenförde, Wilfried von Bredow, Sabine Busse, Edwina S. Campbell, Hartmut Elsenhans, Hans J. Gießmann, Werner Link, Carlo Masala, Hanns W. Maull, and Siegfried Schwarz.
Indonesia’s arduous path to democracy is threatened by several domestic conflicts. Although the civil war in Aceh – a region in the north of Sumatra – has claimed thousands of victims, the incidents have not yet been adequately dealt with – neither in the public domain nor within the scientific community. In May 2003, the Indonesian president, Megawati Sukarnoputri, imposed material law on the Aceh region in order to crack down on the separatist movement Gerakan Aceh Merdeka (GAM). This step does not seem to be in line with serious concepts of democracy and is threatening the consolidation of the transformation process. The author seeks to shed light on the roots of the conflict, the motivation of leading politicians in Jakarta to deploy military means instead of continuing negotiations, and its consequences for the Indonesian process of democratisation.
German foreign policy is in the midst of a far-reaching transformation. Contrary to disciplinary expectations, this process is neither properly captured by descriptions in the liberal tradition („Europeanisation“, „Civilian Power“) nor by Realist expectations that Germany is doomed to „remilitarise“ and/or „renationalise“. However, the key term of foreign policy discourse, „normalisation“, is an unmistakable code, signalling a rediscovery of traditional Realpolitik practices which fit Germany’s current environment. The paper argues that rather than merely playing the role of an obedient disciple of Realpolitik socialisers, Germany ought to rehabilitate the foreign policy tradition of the Bonn Republic in support of an active Idealpolitik transformation of its environment. The article serves as a starting point for a debate on German foreign policy in the upcoming issues of WeltTrends.
Mittelständische Industrieunternehmen setzen für ihre betrieblichen Abläufe Planungs- und Ausführungssysteme ein. Aufgrund der Turbulenzen auf Absatz- und Beschaffungsmärkten kann die Wirtschaftlichkeit und Wettbewerbsfähigkeit dieser Unternehmen nur durch permanente Anpassungen der Organisationsstrukturen und -abläufe erfolgen. In der Praxis zeigt sich eine unzureichende technologische Anpassungsfähigkeit der heute eingesetzten Standardsoftwaresysteme. Diese lassen zwar während der Einführungsphase vielfältige Konfigurationsmöglichkeiten zu, Veränderungen im laufenden Betrieb sind aber meist nur mit großem Aufwand möglich. Hier sind die Softwarehersteller in Zukunft zunehmend gefordert, wandlungsfähige Auftragsabwicklungssysteme zu entwickeln. Über die Entwicklungsphase (Build-Time) hinaus muss auch parallel zur Betriebsphase (Run-Time) der technische Fortschritt aufgrund von geänderten Anforderungen durch entsprechende Softwarereleases synchronisiert werden.
We develop a cluster expansion in space-time for an infinite-dimensional system of interacting diffusions where the drift term of each diffusion depends on the whole past of the trajectory; these interacting diffusions arise when considering the Langevin dynamics of a ferromagnetic system submitted to a disordered external magnetic field.