49 research outputs found

    The Early History of Weighing Technology from the Perspective of a Theory of Innovation

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    The article advances a framework allowing for a unified description of technical innova- tion and the advancement of theoretical knowledge. Cognitive structures based on fore- going actions with physical objects are externally represented by artifacts, language or writing. The exploration of actions with these external representations such as the fabri- cation and usage of new devices or the composition of texts opens up new possibilities for a reflective abstraction leading to new cognitive structures. The exploration of the options for actions is canalized by historically specific contexts constraining the actors. Based on the example of the early history of weighing with a focus on the establishment and differentiation of unequal-arm balances we elaborate the consequences of such an accoun

    Optimisation algorithms for the charge dispatch of plug-in vehicles based on variable tariffs

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    Plug-in vehicles powered by renewable energies are a viable way to reduce local and total emissions and could also support a highly efficient grid operation. Indirect control by variable tariffs is one option to link charging or even discharging time with the grid load and the renewable energy production. Algorithms are required to develop tariffs and evaluate grid impacts of variable tariffs for electric vehicles (BEV) as well as to schedule the charging process optimisation. Therefore a combinatorial optimisation algorithm is developed and an algorithm based on graph search is used and customised. Both algorithms are explained and compared by performance and adequate applications. The developing approach and the correctness of the quick combinatorial algorithm are proved within this paper. For vehicle to grid (V2G) concepts, battery degradation costs have to be considered. Therefore, common life cycle assumptions based on the battery state of charge (SoC) have been used to include degradation costs for different Li-Ion batteries into the graph search algorithm. An application of these optimisation algorithms, like the onboard dispatcher, which is used in the German fleet test "Flottenversuch Elektromobiliät". Grid impact calculations based on the optimisation algorithm are shown. --BEV,V2G,Plug-In-Vehicles (PHEV),optimisation,mobile dispatcher,demand side management,charging,combinatorial algorithm,graph search algorithm,indirect control by variable tariffs

    A Research Program on Innovations in Prehistory and Antiquity

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    The authors discuss the simultaneous appearance of technological innovations in three key technologies (metallurgy, wheeled vehicles, weighing systems) in the second half of the 4th millennium. This is done from a source-critical perspective because the innova- tions are discussed with the help of dynamic maps from the Topoi project Digital Atlas of Innovations. Besides indications of diffusion gradients influenced by special research conditions, exceptional waves of innovation can be detected for all three technologies in the discussed period. These waves of innovation cannot, however, be generalized but have to be understood on the basis of the respective technology traditions and lines of devel- opment specific to local areas. Monocentric diffusion theories can be clearly disproven, local technology developments and their converging in certain centrally situated regions have to be assumed instead. Similarly, the transfer of objects and their châine opératoire can only be detected rather infrequently, while the adaptation to local socio-economic and environmental factors can be demonstrated

    Insightful analysis of historical sources at scales beyond human capabilities using unsupervised Machine Learning and XAI

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    Historical materials are abundant. Yet, piecing together how human knowledge has evolved and spread both diachronically and synchronically remains a challenge that can so far only be very selectively addressed. The vast volume of materials precludes comprehensive studies, given the restricted number of human specialists. However, as large amounts of historical materials are now available in digital form there is a promising opportunity for AI-assisted historical analysis. In this work, we take a pivotal step towards analyzing vast historical corpora by employing innovative machine learning (ML) techniques, enabling in-depth historical insights on a grand scale. Our study centers on the evolution of knowledge within the `Sacrobosco Collection' -- a digitized collection of 359 early modern printed editions of textbooks on astronomy used at European universities between 1472 and 1650 -- roughly 76,000 pages, many of which contain astronomic, computational tables. An ML based analysis of these tables helps to unveil important facets of the spatio-temporal evolution of knowledge and innovation in the field of mathematical astronomy in the period, as taught at European universities

    Decreasing hospital mortality between 1994 and 1998 in patients with acute myocardial infarction treated with primary angioplasty but not in patients treated with intravenous thrombolysis Results from the pooled data of the maximal individual therapy in acute myocardial infarction (MITRA) registry and the myocardial infarction registry (MIR)

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    AbstractOBJECTIVESWe investigated changes in the clinical outcome of primary angioplasty and thrombolysis for the treatment of acute myocardial infarction (AMI) from 1994 to 1998.BACKGROUNDPrimary angioplasty for the treatment of AMI is a sophisticated technical procedure that requires experienced personnel and optimized hospital logistics. Growing experience with primary angioplasty in clinical routine and new adjunctive therapies may have improved the outcome over the years.METHODSThe pooled data of two German AMI registries: the Maximal Individual Therapy in AMI (MITRA) study and the Myocardial Infarction Registry (MIR) were analyzed.RESULTSOf 10,118 lytic eligible patients with AMI, 1,385 (13.7%) were treated with primary angioplasty, and 8,733 (86.3%) received intravenous thrombolysis. Patients characteristics were quite balanced between the two treatment groups, but there was a higher proportion of patients with a prehospital delay of >6 h in those treated with primary angioplasty. The proportion of an in-hospital delay of more than 90 min significantly decreased in patients treated with primary angioplasty over the years (p for trend = 0.015, multivariate odds ratio [OR] for each year of the observation period = 0.84, 95% confidence interval [CI]: 0.73– 0.96) but did not change significantly in patients treated with thrombolysis. Hospital mortality decreased significantly in the primary angioplasty group (p = 0.003 for trend; multivariate OR for each year = 0.73, 95% CI: 0.58– 0.93). However, for patients treated with thrombolysis, hospital mortality did not change significantly (p for trend 0.175, multivariate OR for each year: 1.02, 95% CI: 0.94– 1.11).CONCLUSIONSCompared with thrombolysis the clinical results of primary angioplasty for the treatment of AMI improved from 1994 to 1998. This indicates a beneficial effect of the growing experience and optimized hospital logistics of this technique over the years

    Evaluation der Experimentierklausel nach § 6c SGB II - Untersuchungsfeld 4: Makroanalyse und regionale Vergleiche: Endbericht

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    "Der Beitrag von Untersuchungsfeld 4 - Makroanalyse und regionale Vergleiche - zu den Arbeiten des Forschungsverbundes zur Evaluation der Experimentierklausel nach § 6c SGB II besteht in einer Analyse der Wirkungen unterschiedlicher Formen der Aufgabenwahrnehmung im SGB II auf regionaler Ebene unter Berücksichtigung von regionalen Besonderheiten und gesamtwirtschaftlichen Wirkungszusammenhänge, darunter insbesondere interregionale Verflechtungen sowie Substitutions-, Verdrängungs- und Mitnahmeeffekte. Im Vordergrund steht dabei ein Performancevergleich von Arbeitsgemeinschaften (ARGEn) und zugelassenen kommunalen Trägern (zkT), zugespitzt in der Frage: 'Was wäre geschehen, wenn deutschlandweit entweder das ARGE-Modell oder die kommunale Trägerschaft eingeführt worden wäre?' Zur Beantwortung dieser Frage sind, über rein deskriptive Vergleiche hinaus, Untersuchungen zu den Einflussfaktoren für die Wahl der Form der Aufgabenwahrnehmung und zu den Effekten erforderlich, die sich auf der Ebene der verschiedenen Grundsicherungsstellen bezüglich der Zielsetzungen des SGB II ergeben und der jeweiligen Form der Aufgabenwahrnehmung kausal zugerechnet werden können." (Textauszug

    Evaluation der Experimentierklausel nach § 6c SGB II - Untersuchungsfeld 4: Makroanalyse und regionale Vergleiche: Zwischenbericht 2007

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    "Im Rahmen der Evaluation der Experimentierklausel nach Paragraph 6c SGB II umfasst die Aufgabenstellung des Forschungsfeldes 4 - Makroanalyse und regionale Vergleiche - eine Analyse der regionalen Wirkungen von ARGEn und zkT (zugelassene kommunale Träger), die Analyse der gesamtwirtschaftlichen Wirkungen und ein Performancevergleich der Regionen. Insbesondere im Rahmen der Makroanalyse gilt es die Frage zu beantworten, 'Was wäre geschehen, wenn zum 1. 1. 2005 deutschlandweit entweder das ARGE-Modell oder die kommunale Trägerschaft eingeführt worden wäre?' und zwar unter besonderer Berücksichtigung regionaler Besonderheiten und Verflechtungen, sowie Substitutions-, Verdrängungs- und Mitnahmeeffekten. Bei einem Vergleich der ARGEn mit den zkT muss berücksichtigt werden, ob sich Kreise mit spezifischen Merkmalen für die eine oder die andere Form der Aufgabenwahrnehmung entschieden haben. Auf Grundlage der Vorarbeiten des Paragraph 6c-Forschungsverbundes dürften folgende Faktoren die Optionsneigung beeinflusst haben: Lokale Arbeitsmarktlage, Größe der Kommune, Finanzkraft, Sozio-geographische Merkmale, Politische Merkmale und Vorerfahrungen. Die regionalen Vergleiche dienen der Darstellung und der deskriptiven Beschreibung der Entwicklung zentraler Indikatoren für die Zielgrößen 'Integration in Erwerbstätigkeit', 'Verbesserung der Beschäftigungsfähigkeit' und 'soziale Stabilisierung' im Vergleich der drei Formen der Aufgabenwahrnehmung sowie der unterschiedlichen Organisationstypen." (Autorenreferat
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