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The service-productivity learning cockpit – a business intelligence tool for service enterprises (2012)

Sebastian Walther Gaurang Phadke Torsten Eymann

The paper describes the development of an agent-based simulation tool for hospital managers to manage their productivity of services, especially in the context of supporting services like patient transport logistics. The learning cockpit allows hospital managers to see how the change of inputs changes the overall perceived customer values of all stakeholders and therefore to get a visualization of the impacts their decisions cause. The paper introduces the general research domain service-productivity, followed by a description of the development steps of artefact creation. The learning cockpit is part of a research project called BELOUGA, which is funded by the German government.

Denying access to water? Moral values and commercialization policies in Khartoum governmental water management (2012)

Anne-Sophie Beckedorf

This contribution draws on empirical fieldwork carried out in Khartoum/Sudan in 2009/2010 in order to examine the role of value systems in recent commercialization policies of Khartoum governmental water management. The first section provides background information about the current water supply system in Khartoum, which is a necessary precondition to understand current reform processes. The second section singles out three major aspects of commercialization policies and their contestations in greater detail: increases in water prices, increases in water cuts in case of unpaid water bills, and installations of prepaid water meters. The third section summarizes these contestations and argues that value systems are one major reason why current reform processes are not implemented in the way they were perceived.

Soil moisture fluctuations recorded in Saharan dust deposits on Lanzarote (CanaryIslands) over the last 180 ka (2010)

Hans von Suchodoletz Hedi Oberhänsli Ulrich Hambach Ludwig Zöller Markus Fuchs Dominik Faust

Aeolian sediments trapped in volcanically dammed valleys on Lanzarote, Canary Islands, were investigated in order to reveal environmental changes over the last 180 ka. Clay content and frequency dependent magnetic susceptibility were used as proxies for pedogenesis and palaeo-soil moisture. During the last 180 ka, these proxies showed a general pattern of enhanced soil moisture during glacials and stadials and more arid conditions during interglacials and interstadials. Comparisons of these results with proxies from regional palaeoclimate studies identified a positive correlation with proxies of trade wind strength off northwest Africa and inverse correlations with both sea surface temperatures in the northeast Atlantic and the extent of Mediterranean vegetation. Possible causes for the observed pattern include a glacial enhancement of precipitation from westerly cyclones, a change in relative humidity due to fluctuating air temperatures and an occasional influence of the African summer monsoon. Although it is not yet possible to clearly differentiate among these factors, it is clear that the first two factors must have been primarily dominant. These results represent the first quasi-continuous terrestrial data testifying to environmental changes in the northwest African coastal area for the last 180 ka and complement the abundant data derived from marine cores of the region. High latitude dynamics had a major influence in this area and were intermediated by North Atlantic sea surface temperatures. A possible negative correlation can also be observed with the orbital obliquity cycle with a 10 ka time lag, which is similar to the lag recorded from North Atlantic sea surface temperatures.

Measure and Integration on Lipschitz-Manifolds (2007)

Joachim Naumann Christian G. Simader

The first part of this paper is concerned with various definitions of a k-dimensional Lipschitz-manifold and a discussion of the equivalence of these definitions. The second part is then devoted to the geometrically intrinsic construction of a sigma-algebra L of subsets of the manifold and a measure on L.

Enumeration of integral tetrahedra (2007)

Sascha Kurz

We determine the numbers of integral tetrahedra with diameter d up to isomorphism for all d<=1000 via computer enumeration. Therefore we give an algorithm that enumerates the integral tetrahedra with diameter at most d in O(d^5) time and an algorithm that can check the canonicity of a given integral tetrahedron with at most 6 integer comparisons. For the number of isomorphism classes of integral 4x4 matrices with diameter d fulfilling the triangle inequalities we derive an exact formula.

Geoarchaeological and chronometrical evidence of early human occupation on Lanzarote (Canary Islands) (2003)

Ludwig Zöller Hans von Suchodoletz Nils Küster

Two desert loess–paleosol sequences in sediment traps were investigated using (pedo-) stratigraphy, sedimentology, soil mineralogy and IRSL dating. So far we cannot recognise significant IRSL age-underestimates from the polymineral fine-grain fraction of our samples. We establish a first palaeoclimatic sequence spanning the past ca 200 ka which can be compared to data from other Canary Islands and surrounding areas, including terrestrial and deep sea records. More humid phases on Lanzarote are apparently triggered by Milankovich forcing, but the climate remained semi-arid to arid all over the past 200 ka. The onset of human occupation of the island during a slightly moister period is bracketed between 5 and 10 ka, based on the occurrence of archaeosediments containing bones of ovicaprid. This is the first proof of much earlier occupation than witnessed so far from archaeological records. The early subsidiary economy had a strong impact on soil stability and landscape shaping of the island.

Dating Saharan dust deposits on Lanzarote (Canary Islands) by luminescence dating techniques and their implication for palaeoclimate reconstruction of NW Africa. (2008)

Hans von Suchodoletz Markus Fuchs Ludwig Zöller

Lava flow dammed valleys (Vegas) on Lanzarote (Canary Islands) represent unique sediment traps, filled with autochthonous volcanic material and allochthonous Saharan dust. These sediments and the intercalated palaeosoil sediments document past environmental change of the last glacial-interglacial cycles, both on Lanzarote and in NW Africa. A reliable chronology must be established to use these sediment archives for palaeoclimate reconstructions. Owing to the lack of organic material and the limiting time range of the 14Cdating method, luminescence dating is the most promising method for these sediments. However, the fluvio-eolian character of these sediments is a major problem for luminescence dating, because these sediments are prone to insufficient resetting of the parent luminescence signal (bleaching) prior to sedimentation. To check for the best age estimates, we compare the bleaching behavior of (1) different grain sizes (coarse- versus fine-grain quartz OSL) and (2) different minerals (fine-grain feldspar IRSL versus fine-grain quartz OSL). The results show that owing to its bleaching characteristics, quartz is the preferable mineral for luminescence dating. On the basis of the fine- and coarse-grain quartz OSL age estimates, a chronostratigraphy up to 100 ka could be established. Beyond this age limit for OSL quartz, the chronostratigraphy could be extended up to 180 ka by correlating the vega sediments with dated marine sediment archives.

Response to the „Comment on ’Geoarchaeological and chronometrical evidence …’ ” by J.C. Carracedo et al. (2004)

Ludwig Zöller Hans von Suchodoletz Henrik Blanchard Dominik Faust Ulrich Hambach

This paper is a reply to the comments made by Carracedo et al. (Quaternary Science Reviews 23, 2045-2049) to the original paper by Zöller, L., Suchodoletz, H.von & N. Küster (2003): Geoarchaeological and chronometrical evidence of early human occupation on Lanzarote (Canary Islands), Quaternary Science Reviews 22, 1299-1307. The reply copes with comments concerning chronometrical dating, the origin of investigated material and geomorphologic and geoarchaeologic problems.

Environmental Analysis for Application Layer Networks (2005)

Björn Schnizler Dirk Neumann Daniel Veit Mauro Napoletano Michele Catalano Mauro Gallegati Michael Reinicke Werner Streitberger Torsten Eymann

Die zunehmende Vernetzung von Rechners über das Internet lies die Vision von Application Layer Netzwerken aufkommen. Sie umfassen Overlay Netzwerke wie beispielsweise Peer-to-Peer Netzwerke und Grid Infrastrukturen unter Verwendung des TCP/IP Protokolls. Ihre gemeinsame Eigenschaft ist die redundante, verteilte Bereitstellung und der Zugang zu Daten-, Rechen- und Anwendungsdiensten, während sie die Heterogenität der Infrastruktur vor dem Nutzer verbergen. In dieser Arbeit werden die Anforderungen, die diese Netzwerke an ökonomische Allokationsmechanismen stellen, untersucht. Die Analyse erfolgt anhand eines Marktanalyseprozesses für einen zentralen Auktionsmechanismus und einen katallaktischen Markt.

Analysis and Selection of the Simulation Environment (2005)

Gianfranco Giulioni Floriano Zini

Diese Arbeit analysiert die Anforderungen an eine Simulationsumgebung für die Analyse der Katallaxie. Anhand von Kennzahlen wird die Auswahl der Simulationsumgebung bestimmt.

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