Austrian Academy of Sciences
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Long-Term Effects of Childbearing Postponement
No full textLong-term consequences of childbearing postponement for the population size areconsidered. General relations are obtained, which imply that the cohort NRR, the finalgeneration length, and dynamics of the number of genealogical lines determine the finalpopulation trend. The period fertility rates are not relevant to ultimate population size inthe case of stationary population and have only moderate effect when cohort NRR differsfrom unity. Relations obtained are also of value for formal demography and can be appliedto the fertility transition modeling, population forecasting, and population genetics
Advanced Materials for innovative solar cell technologies - part 1 (NanoTrust-Dossier No 056en - November 2021)
No full textTo achieve the 2050 climate targets set out in the Paris Agreement, novel “emerging photovoltaics” (EPVs) that enable flexible, ultrathin and, above all, lightweight photovoltaic (PV) modules will be used alongside classic siliconbased technologies. Innovative materials, socalled “advanced materials”, open up new application areas and possibilities. Such novel PV systems are based on, for example, perovskite semiconductors, quantum dots, organic polymers or dyes, all of which can be produced easily and cost-effectively. Besides traditional power generation in the form of groundmounted and roofmounted systems, they open up new fields of application such as e.g. portable small devices, building-integrated power generation on facades or window surfaces, or in the transport industry. However, before widespread commercial use is possible, some research and development work is still necessary, especially where increased efficiency and service life are concerned. Since the PV market is currently almost exclusively supplied by silicon-based technologies, and because EPVs do not hold a significant market share, it is not possible to derive future market trends from previous or current ones. Instead, they must be estimated on the basis of existing market segments into which the technology can potentially penetrate. It is necessary to differentiate between application areas where power generation is the main focus and those where local energy supply by PV is the goal, but where the solar cells must fulfil additional functions. As a result, the benefit of EPVs does not lie exclusively in electricity generation per se, but in the possibilities opened up by a targeted local power supply, not taking into account electricity grids
Doing Science, Forgoing Childbearing? Evidence from a Sample of Female Scientists in Austria
No full textAcademic women in Austria and Germany have extraordinarily high final levels ofchildlessness of 45-60%, as documented by prior research. This study investigates howfemale scientists’ fertility behaviour relates to their childbearing ideals and intentions inAustria. It analyses whether high childlessness and low numbers of children are intended ornot. By looking additionally at employment conditions and partnership status, this studypoints to possible obstacles hindering couples to realise their childbearing desires.Furthermore, it shows how female scientists combine their academic career and childcare.The analysis is based on a sample of female scientists who had applied for a grant at theAustrian Academy of Sciences (n=196). It comprises women aged 25-45 who work indifferent scientific fields in Austria. Female scientists aged 40-45 have 0.9 children onaverage and 44% remain childless. However, these levels are far from the number of offspringthat young scientists under the age of 35 intend to have. They perceive on average two as theirideal and intended number; only around 10% want to stay childless. Several obstacles whichimpede childbearing were identified, e.g. the strong work commitment of the femalescientists, the need to be geographically mobile and the high prevalence of living aparttogether relationships. As for the combination of work and family, female scientists returnback to work quickly after they have a child. Most do not regard the family as the maincaregiver but perceive a division of tasks between the family and the public as preferable
The relation between depressive symptoms and age among older Europeans Findings from SHARE
No full textEmpirical evidence on the effects of age on mental health is diverse. Therefore, the paperaims to analyze the association between age and the prevalence of symptoms ofdepression. Based on SHARE, depressive symptoms of 28,069 persons from elevenEuropean countries and Israel aged 50 to 84 years were analyzed using EURO-D.Multivariate regression models were applied to analyze the effect of age on depressivesymptoms under control of socio-economic characteristics and health. The results indicatethat EURO-D scores increased with age and were higher among women compared to men.When controlled by socio-demographic characteristics and health conditions theassociation between depressive symptoms and age almost vanished. The associationbetween depression and age is driven by socio-demographic characteristics and thephysical as well as cognitive health of older persons. Once controlled for these sociodemographiccharacteristics, age no longer had an important explanatory power on themental health of older persons
Geographisches Gezwitscher – Analyse von Twitter-Daten als Methode im GW-Unterricht. GW-Unterricht|GW-Unterricht 164|
No full textSoziale Medien sind ein wesentlicher Bestandteil des Alltags von Schüler*innen und gleichzeitig zunehmend wichtig in Wirtschaft, Politik und Wissenschaft. Am Beispiel von Twitter zeigt dieser Beitrag, dass soziale Medien im Unterricht auch für die Beantwortung geographischer Fragestellungen verwendet werden können. Hierfür eignen sich Twitter-Daten aufgrund ihrer Georeferenzierung und weiterer interessanter Inhalte besonders. Der Beitrag gibt einen Überblick über die Verwendung von Twitter für sozialwissenschaftliche und humangeographische Fragestellungen und reflektiert die Nutzung von Twitter im Unterricht. Für die Unterrichtspraxis werden Beispiele zu den Themen Braunkohle, Flutereignisse und Raumwahrnehmungen sowie Anleitungen zur Auswertung, Anwendung und Reflexion von Twitter-Analysen vorgestellt
Didaktischer Einsatz von Online-Fragebögen im GW-Unterricht. Das Beispiel der Wegzugsmotivationen Jugendlicher. GW-Unterricht|GW-Unterricht 164|
No full textIn der humangeographischen Forschung sind Fragebögen ein zentrales Instrument und zunehmend finden gerade Online- Fragebögen besondere Beachtung. Am Beispiel der Beforschung von Wegzugsmotivationen Jugendlicher diskutiert dieser Beitrag im ersten Teil die Arbeitsschritte bei der Erstellung und Auswertung von Online-Fragebögen. Im zweiten Teil wird dies auf die Schulpraxis übertragen, indem einerseits die Potenziale und Andockmöglichkeiten von Online-Fragebögen für den Unterrichtseinsatz skizziert werden und andererseits ein Beispiel einer Unterrichtssequenz vorgestellt wird
A comparison of reduced-order modeling approaches using artificial neural networks for PDEs with bifurcating solutions. ETNA - Electronic Transactions on Numerical Analysis
No full textThis paper focuses on reduced-order models (ROMs) built for the efficient treatment of PDEs having solutions that bifurcate as the values of multiple input parameters change. First, we consider a method called local ROM that uses k-means algorithm to cluster snapshots and construct local POD bases, one for each cluster. We investigate one key ingredient of this approach: the local basis selection criterion. Several criteria are compared and it is found that a criterion based on a regression artificial neural network (ANN) provides the most accurate results for a channel flow problem exhibiting a supercritical pitchfork bifurcation. The same benchmark test is then used to compare the local ROM approach with the regression ANN selection criterion to an established global projection-based ROM and a recently proposed ANN based method called POD-NN. We show that our local ROM approach gains more than an order of magnitude in accuracy over the global projection-based ROM. However, the POD-NN provides consistently more accurate approximations than the local projection-based ROM
Population Structure and Consumption Growth: Evidence from National Transfer Accounts
No full textWe assess the impact of population structure on economic growth. Following recent research, we focus on the generational turnover as a key driver of consumption growth. We characterize the impact of the average birth and death rates on the generational turnover, depending on the age-profile of consumption and on the extent of annuity market imperfection. Using recent data from the National Transfer Accounts on consumption profiles for a number of countries, we assess in a comparative way the sign and magnitude of generational turnover and its impact on consumption growth. We find considerable cross-country variation and trace it back to differences in demographic rates and in the consumption structure
The Legality Principle in Athenian Law: Response to Michael Gagarin. Akten der Gesellschaft für Griechische und Hellenistische Rechtsgeschichte|(28) Symposion 2019 Akten der Gesellschaft für griechische und hellenistische Rechtsgeschichte Band 28|
No full textPotential and challenges of the Serengeti-Ngorongoro Biosphere Reserve, Tanzania. eco.mont (Journal on Protected Mountain Areas Research and Management)|eco.mont Vol. 13 special issue 2021|
No full textThis article examines whether the Serengeti-Ngorongoro Biosphere Reserve, Tanzania, is successfully mitigating the immense challenges that rising population density and growing land-use pressure, as well as climate change and tourism, pose to vulnerable biodiversity hotspots, such as ancient Afromontane forests. The biosphere reserve’s management approach to ecological and socio-cultural heritage was analysed using the Global-Local Drivers of Change model as a theoretical basis, together with The Economics of Ecosystems and Biodiversity (TEEB) analysis framework. This empirical study of a relatively old Sub-Saharan African biosphere reserve (established in 1981) used a qualitative research approach, where data was collected from focus groups living in the reserve, and semi-structured interviews with Ngorongoro Conservation Area officials and other main stakeholders. Results show that the management focus on environmental conservation over socio-cultural heritage has led to population growth, cultural change and landscape transformation, leading to human-wildlife conflicts and negative park-people relationships. It is concluded that this biosphere reserve needs to better exploit its vast potential and adjust its institutional structure and operational strategies to align with modern Other Effective Area-Based Conservation Methods