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In this paper Lie group method in combination with Magnus expansion is utilized to develop a universal method applicable to solving a Sturm–Liouville problem (SLP) of any order with arbitrary boundary conditions. It is shown that the method has ability to solve direct regular (and some singular) SLPs of even orders (tested for up to eight), with a mix of (including non-separable and finite singular endpoints) boundary conditions, accurately and efficiently. The present technique is successfully applied to overcome the difficulties in finding suitable sets of eigenvalues so that the inverse SLP problem can be effectively solved. The inverse SLP algorithm proposed by Barcilon (1974) is utilized in combination with the Magnus method so that a direct SLP of any (even) order and an inverse SLP of order two can be solved effectively.
In this paper, we investigate the continuous version of modified iterative Runge–Kutta-type methods for nonlinear inverse ill-posed problems proposed in a previous work. The convergence analysis is proved under the tangential cone condition, a modified discrepancy principle, i.e., the stopping time T is a solution of ∥𝐹(𝑥𝛿(𝑇))−𝑦𝛿∥=𝜏𝛿+ for some 𝛿+>𝛿, and an appropriate source condition. We yield the optimal rate of convergence.
This study presents the first suite of apatite fission-track (AFT) ages from the SE part of the Western Sudetes. AFT cooling ages from the Orlica-snie(z) over dotnik Dome and the Upper Nysa Klodzka Graben range from Late Cretaceous (84 Ma) to Early Palaeocene-Middle Eocene (64-45 Ma). The first stage of basin evolution (similar to 100-90 Ma) was marked by the formation of a local extensional depocentre and disruption of the Mesozoic planation surface. Subsequent far-field convergence of European microplates resulted in Coniacian-Santonian (similar to 89-83 Ma) thrust faulting. AFT data from both metamorphic basement and Mesozoic sedimentary cover indicate homogenous Late Cretaceous burial of the entire Western Sudetes. Thermal history modeling suggests that the onset of cooling could be constrained between 89 and 63 Ma with a climax during the Palaeocene-Middle Eocene basin inversion phase.
Bank filtration (BF) is an established indirect water-treatment technology. The quality of water gained via BF depends on the subsurface capture zone, the mixing ratio (river water versus ambient groundwater), spatial and temporal distribution of subsurface travel times, and subsurface temperature patterns. Surface-water infiltration into the adjacent aquifer is determined by the local hydraulic gradient and riverbed permeability, which could be altered by natural clogging, scouring and artificial decolmation processes. The seasonal behaviour of a BF system in Germany, and its development during and about 6 months after decolmation (canal reconstruction), was observed with a long-term monitoring programme. To quantify the spatial and temporal variation in the BF system, a transient flow and heat transport model was implemented and two model scenarios, 'with' and 'without' canal reconstruction, were generated. Overall, the simulated water heads and temperatures matched those observed. Increased hydraulic connection between the canal and aquifer caused by the canal reconstruction led to an increase of similar to 23% in the already high share of BF water abstracted by the nearby waterworks. Subsurface travel-time distribution substantially shifted towards shorter travel times. Flow paths with travel times <200 days increased by similar to 10% and those with <300 days by 15%. Generally, the periodic temperature signal, and the summer and winter temperature extrema, increased and penetrated deeper into the aquifer. The joint hydrological and thermal effects caused by the canal reconstruction might increase the potential of biodegradable compounds to further penetrate into the aquifer, also by potentially affecting the redox zonation in the aquifer.
Assessments of psychotherapeutic competencies play a crucial role in research and training. However, research on the reliability and validity of such assessments is sparse. This study aimed to provide an overview of the current evidence and to provide an average interrater reliability (IRR) of psychotherapeutic competence ratings. A systematic review was conducted, and 20 studies reported in 32 publications were collected. These 20 studies were included in a narrative synthesis, and 20 coefficients were entered into the meta-analysis. Most primary studies referred to cognitive-behavioral therapies and the treatment of depression, used the Cognitive Therapy Scale, based ratings on videos, and trained the raters. Our meta-analysis revealed a pooled ICC of 0.82, but at the same time severe heterogeneity. The evidence map highlighted a variety of variables related to competence assessments. Further aspects influencing the reliability of competence ratings and regarding the considerable heterogeneity are discussed in detail throughout the manuscript.
Concepts and theory
(2019)
There is no threat to Western democracies today comparable to the rise of right-wing populism. While it has played an increasing role at least since the 1990s, only the social consequences of the global financial crises in 2008 have given it its break that led to UK’s ‘Brexit’ and the election of Donald Trump as US President in 2016, as well as promoting what has been called left populism in countries that were hit the hardest by both the banking crisis and consequential neo-liberal austerity politics in the EU, such as Greece and Portugal.
In 2017, the French Front National (FN) attracted many voters in the French Presidential elections; we have seen the radicalization of the Alternative für Deutschland (AfD) in Germany and the formation of centre-right government in Austria. Further, we have witnessed the consolidation of autocratic regimes, as in the EU member states Poland and Greece. All these manifestations of right-wing populism share a common feature: they attack or even compromise the core elements of democratic societies such as the separation of powers, protection of minorities, or the rule of law.
Despite a broad debate on the re-emergence of ‘populism’ in the transition from the twentieth to the twenty-first century that has brought forth many interesting findings, a lack of sociological reasoning cannot be denied, as sociology itself withdrew from theorising populism decades ago and largely left the field to political sciences and history. In a sense, Populism and the Crisis of Democracy considers itself a contribution to begin filling this lacuna. Written in a direct and clear style, this set of volumes will be an invaluable reference for students and scholars in the field of political theory, political sociology and European Studies.
This volume Concepts and Theory offers new and fresh perspectives on the debate on populism. Starting from complaints about the problems of conceptualising populism that in recent years have begun to revolve around themselves, the chapters offer a fundamental critique of the term and concept of populism, theoretically inspired typologies and descriptions of currently dominant concepts, and ways to elaborate on them. With regard to theory, the volume offers approaches that exceed the disciplinary horizon of political science that so far has dominated the debate. As sociological theory so far has been more or less absent in the debate on populism, only few efforts have been made to discuss populism more intensely within different theoretical contexts in order to explain its dynamics and processes. Thus, this volume offers critical views on the debate on populism from the perspectives of political economy and the analysis of critical historical events, the links of analyses of populism with social movement mobilisation, the significance of ‘superfluous populations’ in the rise of populism and an analysis of the exclusionary character of populism from the perspective of the theory of social closure.
This article draws on the experience from an ongoing research project employing respondent-driven sampling (RDS) to survey (illicit) 24-hour home care workers. We highlight issues around the preparatory work and the fielding of the survey to provide researchers with useful insights on how to implement RDS when surveying populations for which the method has not yet been used. We conclude the article with ethical considerations that occur when employing RDS.
This paper compares the usability of data stemming from probability sampling with data stemming from nonprobability sampling. It develops six research scenarios that differ in their research goals and assumptions about the data generating process. It is shown that inferences from data stemming from nonprobability sampling implies demanding assumptions on the homogeneity of the units being studied. Researchers who are not willing to pose these assumptions are generally better off using data from probability sampling, regardless of the amount of nonresponse. However, even in cases when data from probability sampling is clearly advertised, data stemming from nonprobability sampling may contribute to the cumulative scientific endeavour of pinpointing a plausible interval for the parameter of interest.
Classical Wolf-Rayet (cWR) stars are at a crucial evolutionary stage for constraining the fates of massive stars. The feedback of these hot, hydrogen-depleted stars dominates their surrounding by tremendous injections of ionizing radiation and kinetic energy. The strength of a Wolf-Rayet (WR) wind decides the eventual mass of its remnant, likely a massive black hole. However, despite their major influence and importance for gravitational wave detection statistics, WR winds are particularly poorly understood. In this paper, we introduce the first set of hydrodynamically consistent stellar atmosphere models for cWR stars of both the carbon (C) and the nitrogen (N) sequence, i.e. WC and WN stars, as a function of stellar luminosity-to-mass ratio (or Eddington Gamma) and metallicity. We demonstrate the inapplicability of the CAK wind theory for cWR stars and confirm earlier findings that their winds are launched at the (hot) iron (Fe) opacity peak. For log Z/Z(circle dot) > -2, Fe is also the main accelerator throughout the wind. Contrasting previous claims of a sharp lower mass-loss limit forWR stars, we obtain a smooth transition to optically thin winds. Furthermore, we find a strong dependence of the mass-loss rates on Eddington Gamma, both at solar and subsolar metallicity. Increases inWCcarbon and oxygen abundances turn out to slightly reduce the predicted mass-loss rates. Calculations at subsolar metallicities indicate that below the metallicity of the Small Magellanic Cloud, WR mass-loss rates decrease much faster than previously assumed, potentially allowing for high black hole masses even in the local Universe.
We examine how and under what conditions informal institutional constraints, such as precedent and doctrine, are likely to affect collective choice within international organisations even in the absence of powerful bureaucratic agents. With a particular focus on the United Nations Security Council, we first develop a theoretical account of why such informal constraints might affect collective decisions even of powerful and strategically behaving actors. We show that precedents provide focal points that allow adopting collective decisions in coordination situations despite diverging preferences. Reliance on previous cases creates tacitly evolving doctrine that may develop incrementally. Council decision-making is also likely to be facilitated by an institutional logic of escalation driven by institutional constraints following from the typically staged response to crisis situations. We explore the usefulness of our theoretical argument with evidence from the Council doctrine on terrorism that has evolved since 1985. The key decisions studied include the 1992 sanctions resolution against Libya and the 2001 Council response to the 9/11 attacks. We conclude that, even within intergovernmentally structured international organisations, member states do not operate on a clean slate, but in a highly institutionalised environment that shapes their opportunities for action.
Professional development on fostering students’ academic language proficiency across the curriculum
(2019)
This meta-analysis aggregates effects from 10 studies evaluating professional development interventions aimed at qualifying in-service teachers to support their students in mastering academic language skills while teaching their respective subject areas. The analysis of a subset of studies revealed a small non-significant weighted training effect on teachers' cognition (g' = 0.21, SE = 0.14). An effect aggregation including all studies (with 650 teachers) revealed a medium to large weighted overall effect on teachers' classroom practices (g' = 0.71, SE = 0.16). Methodological variables moderated the effect magnitude. Nevertheless, the results suggest professional development is beneficial for improving teachers' practice.
Duplicate detection algorithms produce clusters of database records, each cluster representing a single real-world entity. As most of these algorithms use pairwise comparisons, the resulting (transitive) clusters can be inconsistent: Not all records within a cluster are sufficiently similar to be classified as duplicate. Thus, one of many subsequent clustering algorithms can further improve the result. <br /> We explain in detail, compare, and evaluate many of these algorithms and introduce three new clustering algorithms in the specific context of duplicate detection. Two of our three new algorithms use the structure of the input graph to create consistent clusters. Our third algorithm, and many other clustering algorithms, focus on the edge weights, instead. For evaluation, in contrast to related work, we experiment on true real-world datasets, and in addition examine in great detail various pair-selection strategies used in practice. While no overall winner emerges, we are able to identify best approaches for different situations. In scenarios with larger clusters, our proposed algorithm, Extended Maximum Clique Clustering (EMCC), and Markov Clustering show the best results. EMCC especially outperforms Markov Clustering regarding the precision of the results and additionally has the advantage that it can also be used in scenarios where edge weights are not available.
Industry 4.0, based on increasingly progressive digitalization, is a global phenomenon that affects every part of our work. The Internet of Things (IoT) is pushing the process of automation, culminating in the total autonomy of cyber-physical systems. This process is accompanied by a massive amount of data, information, and new dimensions of flexibility. As the amount of available data increases, their specific timeliness decreases. Mastering Industry 4.0 requires humans to master the new dimensions of information and to adapt to relevant ongoing changes. Intentional forgetting can make a difference in this context, as it discards nonprevailing information and actions in favor of prevailing ones. Intentional forgetting is the basis of any adaptation to change, as it ensures that nonprevailing memory items are not retrieved while prevailing ones are retained. This study presents a novel experimental approach that was introduced in a learning factory (the Research and Application Center Industry 4.0) to investigate intentional forgetting as it applies to production routines. In the first experiment (N = 18), in which the participants collectively performed 3046 routine related actions (t1 = 1402, t2 = 1644), the results showed that highly proceduralized actions were more difficult to forget than actions that were less well-learned. Additionally, we found that the quality of cues that trigger the execution of routine actions had no effect on the extent of intentional forgetting.
Selfish Network Creation focuses on modeling real world networks from a game-theoretic point of view. One of the classic models by Fabrikant et al. (2003) is the network creation game, where agents correspond to nodes in a network which buy incident edges for the price of alpha per edge to minimize their total distance to all other nodes. The model is well-studied but still has intriguing open problems. The most famous conjectures state that the price of anarchy is constant for all alpha and that for alpha >= n all equilibrium networks are trees. We introduce a novel technique for analyzing stable networks for high edge-price alpha and employ it to improve on the best known bound for the latter conjecture. In particular we show that for alpha > 4n - 13 all equilibrium networks must be trees, which implies a constant price of anarchy for this range of alpha. Moreover, we also improve the constant upper bound on the price of anarchy for equilibrium trees.
Based upon the current debate on international practices with its focus on taken-for-granted everyday practices, we examine how Security Council practices may affect member state action and collective decisions on intrastate conflicts. We outline a concept that integrates the structuring effect of practices and their emergence from interaction among reflective actors. It promises to overcome the unresolved tension between understanding practices as a social regularity and as a fluid entity. We analyse the constitutive mechanisms of two Council practices that affect collective decisions on intrastate conflicts and elucidate how even reflective Council members become enmeshed with the constraining implications of evolving practices and their normative implications. (1) Previous Council decisions create precedent pressure and give rise to a virtually uncontested permissive Council practice that defines the purview for intervention into such conflicts. (2) A ratcheting practice forces opponents to choose between accepting steadily reinforced Council action, as occurred regarding Sudan/Darfur, and outright blockade, as in the case of Syria. We conclude that practices constitute a source of influence that is not captured by the traditional perspectives on Council activities as the consequence of geopolitical interests or of externally evolving international norms like the ‘responsibility to protect’ (R2P).