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Die Auswirkungen des Einsatzes moderner Informationsund Kommunikationstechnologien (IuK) werden oftmals unter dem Schlagwort der Globalisierung zusammengefaßt. IuK-Technologien stellen die technischen Voraussetzungen beispielsweise für die weitgehende Vernetzung von Unternehmen, für neue Formen der Arbeitsteilung und -kooperation.Im Fokus der wissenschaftlichen Diskussion um E-Commerce stehen Veränderungen auf globaler Ebene, die Frage nach den möglichen, raumwirksamen Veränderungen in den Regionen wird dagegen nur wenig diskutiert. Was aber bedeutet der Einsatz von E-Commerce konkret für Absatzmärkte, Kunden- und Lieferantenbeziehungen auf der regionalen Ebene? Besteht die Gefahr einer Schwächung insbesondere der mittelständischen, meist regional verankerten Betriebe oder bietet E-Commerce gerade für die kleineren und mittleren Unternehmen (KMU) die Chance eines Innovationsschubs? Ein Blick auf die regionale Ebene zeigt, daß hier zahlreiche Förderaktivitäten unternommen werden. Dies wirft Fragen auf: Welche Strategien sind bei dieser Förderung erkennbar? Wie geht die traditionelle Wirtschaftsförderung mit diesem für sie neuen Thema um?
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In the Andes, there are several pre-Hispanic irrigation networks with structures destined for water storage. However, it has not been widely discussed in archaeological research. This is probably due to their being difficult to identify. The aim of this study is to explore the use of diatom assemblage analysis as a methodological tool suitable to help in the identification and characterization of these ancient hydraulic structures. We analyzed two archaeological structures interpreted as water reservoirs from north-western Argentina (EH1 in Antofagasta de la Sierra and U-88R1 in Yocavil) and compared them to current reservoirs. The diatom species composition and the changes in the dominant ecological groups in the studied structures highlight different periods of hydraulic behavior. EH1 contained and stored water, but there were periods of time in which there was a lack of use or abandonment of the structure. However, the U88-R1 structure does not have diatom evidence of containing standing water for a prolonged time but presence of wet soils. Thus, the structure could have been used for other water management strategies. The results show that diatom analysis is a methodological tool with a high potential to study ancestral hydrotechnologies.  相似文献   
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City dwellers occasionally must seek jobs, dwellings, or particular services or goods. Two very different ways exist by which the individual may conduct such a search. Lacking prior information, the person may elect to visit perceived possible locations until an appropriate one is found. Alternatively, an address may first be ascertained and then visited by finding a path to it. Clearly, there is a substantial difference between these two methods in terms of the amount of spatial movement they require in order to satisfy the searcher's needs. In this paper, this difference is modeled for situations that vary in terms of the density of acceptable end points of the search, as well as in characteristics of the signs of these end points, their patterns, and the level of information with which the searcher may begin.  相似文献   
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This article examines the introduction of blood transfusion into general practice from the end of the First World War to the Second World War. Developments during most of this period were not the result of new discoveries but rather the spread of ideas and the establishment of donor organizations to secure an adequate blood supply. The identification, testing, and organization of potential donors were done in a wide variety of settings that reflected differences in political and cultural experiences. At the end of the 1930s, with war approaching, the resolution of problems with storage of blood and the discovery of new techniques for separating and storing plasma dramatically changed transfusion practice. Thus, the innovations of the Second World War were very much based on the development of broad donor organizations plus the new technical discoveries that had occurred during the interwar period.  相似文献   
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The Poema de Fernán González (or Libro del conde de Castilla) is not a crusade song, nor is it an epic poem or a historical account commemorating the foundation of San Pedro de Arlanza Monastery. It is rather a hybrid text that employs all the literary and historical resources available around the middle of the thirteenth century to an educated poet who was intent on transmitting to future generations the memory of the Count who made possible the independence of Castile. All episodes in the poem point to Castile's unique place in history, describing through the protagonist's bellicose deeds its hegemonic ascendency as the most important kingdom of the Iberian peninsula. Its destiny is determined by the hero's combative character against all enemies, whether Christians or Moors, and more specifically by confronting the powerful kings of neighboring states León and Navarre.  相似文献   
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