cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Continuous and Discontinuous Transitions in the Depinning of Two-Dimensional Dusty Plasmas on a One-Dimensional Periodic Substrate
Creators: name: Gu, L.
name: Li, W.
name: Reichhardt, C.
name: Reichhardt, C. J. O.
name: Murillo, M. S.
name: Feng, Yan
Publisher: name: arXiv
Year: 2020
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Langevin dynamical simulations are performed to study the depinning dynamics of two-dimensional dusty plasmas on a one-dimensional periodic substrate. From the diagnostics of the sixfold coordinated particles $P_6$ and the collective drift velocity $V_x$, three different states appear, which are the pinning, disordered plastic flow, and moving ordered states. It is found that the depth of the substrate is able to modulate the properties of the depinning phase transition, based on the results of $P_6$ and $V_x$, as well as the observation of hysteresis of $V_x$ while increasing and decreasing the driving force monotonically. When the depth of the substrate is shallow, there are two continuous phase transitions. When the potential well depth slightly increases, the phase transition from the pinned to the disordered plastic flow states is continuous; however, the phase transition from the disordered plastic flow to the moving ordered states is discontinuous. When the substrate is even deeper, the phase transition from the pinned to the disordered plastic flow states changes to discontinuous. When the substrate further increases, as the driving force increases, the pinned state changes to the moving ordered state directly, so that the disordered plastic flow state disappears completely.
description: 9 pages, 5 postscript figures
title: Kinderbetreuung in der Corona-Krise: Wer betreut, wenn Schulen und Kitas schließen? Wie der berufliche Alltag von erwerbstätigen Eltern die Kinderbetreuung während des Lockdowns beeinflusst hat
Creators: name: Zoch, Gundula
name: Bächmann, Ann-Christin
name: Vicari, Basha
Publisher: name: LIfBi Leibniz Institute for Educational Trajectories
Year: 2020
Subjects: subject: COVID-19
subject: NEPS-C

description: Um die Ausbreitung des Coronavirus einzudämmen, blieben in Deutschland alle Schulen und Kindertagesstätten über mehrere Monate geschlossen. Dies hat vor allem berufstätige Eltern vor besondere Herausforderungen gestellt. Mit Hilfe von Daten des Nationalen Bildungspanels (NEPS) zeigt dieser Bericht, wie Eltern die Betreuung ihrer Kinder in den ersten Monaten der COVID-19-Pandemie organisiert haben. Zwei Fragen stehen dabei im Mittelpunkt: Von wem wurden Schul- und Kitakinder während dieser Zeit betreut? Und wie hat der berufliche Alltag von erwerbstätigen Müttern und Vätern die Kinderbetreuung beeinflusst?
description: NEPS Berichte Corona, No. 3 (2020)
title: Zufriedenheit in unruhigen Zeiten: Welche Rolle die Kommunikation zwischen Eltern und Schulen während der Schulschließungen gespielt hat. Einschätzungen von Eltern zur Unterstützung durch die Schule und zum Lernerfolg ihrer Kinder während des Lockdowns
Creators: name: Attig, Manja
name: Wolter, Ilka
name: Nusser, Lena
Publisher: name: LIfBi Leibniz Institute for Educational Trajectories
Year: 2020
Subjects: subject: COVID-19
subject: NEPS-C

description: In der Zeit der Schulschließungen aufgrund der Covid-19-Pandemie zu Beginn des Jahres 2020 mussten sich Schülerinnen und Schüler sowie ihre Lehrkräfte und Eltern an vielen Stellen auf neue Situationen einstellen. Das Gelingen des Lernens zuhause war dabei nicht nur von technischen Voraussetzungen abhängig. Die aktuelle Auswertung der Corona-Zusatzbefragung im Nationalen Bildungspanel (NEPS) zeigt, wie wichtig in dieser Phase eine transparente Kommunikation zwischen Schulen und Elternhäusern war. Der Bericht beleuchtet, wie zufrieden Eltern von Achtklässlerinnen und -klässlern mit der Unterstützung durch ihre Schulen in der Zeit des Lernens zuhause waren und wie Eltern den wahrgenommenen Lernerfolg ihrer Kinder in dieser Zeit einschätzten.
description: NEPS Berichte Corona, No. 4 (2020)
title: Lernen im Lockdown: Welche Voraussetzungen helfen Schülerinnen und Schülern? Die Bedeutsamkeit der Lesekompetenz, des Interesses an Lerninhalten und der Anstrengungsbereitschaft für die Bewältigung des Lernens zuhause
Creators: name: Lockl, Kathrin
name: Attig, Manja
name: Nusser, Lena
name: Wolter, Ilka
Publisher: name: LIfBi Leibniz Institute for Educational Trajectories
Year: 2021
Subjects: subject: COVID-19
subject: NEPS-C

description: Die Schulschließungen in der Corona-Krise stellen Eltern und Kinder ebenso wie Schulen und Lehrkräfte vor große Herausforderungen. Im Vergleich zu einem regulären Schulbetrieb spielt das selbständige Lernen alleine zuhause für Schülerinnen und Schüler eine viel größere Rolle. Die Daten des Nationalen Bildungspanels (NEPS) bieten nicht nur eine Momentaufnahme, wie es den Familien im Frühjahr 2020 beim Homeschooling ging, sondern lassen rückblickend auch Schutzfaktoren für Schülerinnen und Schülern identifizieren: Welche Voraussetzungen und Kompetenzen helfen Schülerinnen und Schülern, das Lernen zuhause und die damit einhergehenden Herausforderungen gut zu meistern? Welche Rolle spielen hierbei ihre Lesekompetenz, ihr Interesse an den Lerninhalten und ihre Bereitschaft, sich beim Lernen anzustrengen?
description: NEPS Berichte Corona, No. 5 (2020)
title: Nach dem Brexit
title: eine neue Debatte über Erweiterung und Vertiefung der EU
titleType: Subtitle
Creators: name: Lippert, Barbara
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP-Aktuell, 7/2021
title: Governance of the water-energy-food nexus for an integrated implementation of the 2030 Agenda
Creators: name: Srigiri, Srinivasa Reddy
name: Dombrowsky, Ines
Publisher: name: German Development Institute / Deutsches Institut für Entwicklungspolitik (DIE)
publisherIdentifier: https://ror.org/01t3zke88
publisherIdentifierScheme: ROR
Year: 2021
Subjects: subject: water-energy-food nexus
subject: governance
subject: polycentricity
subject: coordination
subject: 2030 Agenda
subject: Sustainable development Goals (SDGs)

description: Implementing the 2030 Agenda requires an improved understanding of the interdependencies among the Sustainable Development Goals (SDGs) and targets and the design and implementation of coherent policies across different levels and sectors. The water-energy-food (WEF) nexus has emerged over the past decade as a useful concept to reduce trade-offs and increase synergies in promoting goals of water, energy and food security. While WEF scholarship substantiates the biophysical interlinkages and calls for increased and effective coordination across sectors and levels, knowledge about the conditions for effective coordination is lacking. We aim to contribute to this understanding by conceptualising WEF nexus governance from an analytical perspective as a polycentric system and by developing a framework based on the concept of networks of adjacent action situations (NAASs).

 The interdependence among transactions for pursuing WEF securities by actors in the differing action situations generates a need for coordination in changing or sustaining institutions, policy goals and policy instruments that guide actions leading to sustainable outcomes. Coordination is achieved through arrangements based on cooperation, coercion and competition. Coordination in complex social-ecological systems is unlikely to be achieved by a single governance mode but rather by synergistic combinations of such modes. Particular coordination arrangements that emerge in a given context depend on the distribution of authority, information and resources within and across interlinked decision-making centres. Integrating the political ecology-based conceptualisations of power into the analytical framework further extends the governance analysis to include the influence of power relations on coordination. Methodological innovation in delineating action situations and identifying the unit of analysis as well as integrating different sources and types of data are required to operationalise the conceptual framework.
description: Discussion Paper, 2/2021
title: Machtkampf in Venezuela: Auswege aus der Sackgasse
title: ein Rettungspaket muss jetzt geschnürt werden
titleType: Subtitle
Creators: name: Maihold, Günther
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP-Aktuell, 8/2021
title: A behavioural perspective on the drivers of migration: studying economic and social preferences using the Gallup World Poll
Creators: name: Klöble, Katrin
Publisher: name: German Development Institute / Deutsches Institut für Entwicklungspolitik (DIE)
publisherIdentifier: https://ror.org/01t3zke88
publisherIdentifierScheme: ROR
Year: 2021
Subjects: subject: flight and migration
subject: displacement
subject: Middle East and North Africa
subject: MENA

description: This paper addresses the self-selection of potential migrants. In particular, the study examines whether risk and time preferences explain a significant proportion in the movement heterogeneity of individuals. It is further intended to shed light on the role of social preferences (trust, altruism, reciprocity) as potential migratory determinants. By making use of a unique cross-sectional data set on migration intentions (Gallup World Poll) and experimentally-validated preferences (the Global Preference Survey) covering 70 countries worldwide, a probit model is estimated. The empirical results provide evidence that potential migrants exhibit higher levels of risk-taking and patience than their counterparts who stay at home (the stayers). This holds true across differing countries with various cultural backgrounds and income levels. Trust and negative reciprocity are found to be significantly related to migration aspirations as well. Yet conclusive clarifications still remain necessary, providing impetuses for future research.
description: Discussion Paper, 4/2021
title: The impact of patient capital on job quality, investments and firm performance: cross-country evidence on long-term finance
Creators: name: Sommer, Christoph
Publisher: name: German Development Institute / Deutsches Institut für Entwicklungspolitik (DIE)
publisherIdentifier: https://ror.org/01t3zke88
publisherIdentifierScheme: ROR
Year: 2021
Subjects: subject: corporate finance
subject: long-term finance
subject: loans
subject: job quality
subject: decent work
subject: investments
subject: firm performance
subject: economic growth

description: Despite its importance for development, long-term finance is particularly scarce in countries with lower income levels. This not only results in unrealised growth and employment creation at the national level and at the level of individual firms, but also undermines a broader shift towards better jobs. After all, many long-term investments comprise investments in labour that have the potential to contribute to improvements in the quality of jobs, through training to boost skill levels, the creation of more stable employment relationships, and the higher wages that result. This paper uses more than 17,000 firm-level observations from 73 mostly low- and middle-income countries between 2002 and 2009 to provide the first empirical evidence of the extent to which long-term finance affects the quality of jobs. Additionally, it looks into effects on investments and the performance of firms. The findings, based on inverse probability weighted regression adjustment, indicate that firms with long-term finance exhibit a share of permanent employees that is 0.9 percentage points higher, and train an additional 2.4 per cent of their production workers. The probability that firms invest in fixed assets or in innovations in their production process both increase by more than 5.5 percentage points, while employment and sales growth rises as well. The fact that the positive effects on job quality mostly disappear when defining long-term finance as loans with a maturity of more than one year instead of more than two years, underlines the importance of longer loan maturities for better jobs. Despite presenting favourable theoretical and descriptive arguments, it cannot be ruled out completely that unobservable variables affect the estimation of effect sizes.
description: Discussion Paper, 6/2021
Active Matter Commensuration and Frustration Effects on Periodic Substrates
Creators: name: Reichhardt, C.
name: Reichhardt, C. J. O.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We show that self-driven particles coupled to a periodic obstacle array exhibit novel active matter commensuration effects that are absent in the Brownian limit. As the obstacle size is varied for sufficiently large activity, a series of commensuration effects appear in which the motility induced phase separation produces commensurate crystalline states, while for other obstacle sizes we find frustrated or amorphous states. The commensuration effects are associated with peaks in the amount of six-fold ordering and the maximum cluster size. When a drift force is added to the system, the mobility contains peaks and dips similar to those found in transport studies for commensuration effects in superconducting vortices and colloidal particles.
description: 5 pages, 4 postscript figures
title: Die "Takfiristen"
title: eine salafistisch-jihadistische Teilströmung gewinnt an Bedeutung
titleType: Subtitle
Creators: name: Steinberg, Guido
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP-Aktuell, 9/2021
title: Regionale Kontextdaten mit dem Mikrozensus
Creators: name: Pforr, Klaus
Publisher: name: SSOAR -   GESIS Leibniz Institute for the Social Sciences
Year: 2021
Subjects: subject: 10105 Methods and Techniques of Data Collection and Data Analysis, Statistical Methods, Computer Methods
subject: data capture
subject: data quality
subject: microcensus
subject: estimation
subject: data preparation
subject: regional distribution
subject: survey research

description: GESIS Papers, 2021/02, 42 S.
title: Strengthening health systems worldwide
title: a new role for the ECDC
titleType: Subtitle
Creators: name: Bergner, Susan
name: Kump, Isabell
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP Comment, 11/2021
Drive Dependence of the Hall Angle for a Sliding Wigner Crystal in a Magnetic Field
Creators: name: Reichhardt, C.
name: Reichhardt, C. J. O.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We numerically examine the depinning and sliding dynamics of a Wigner crystal in the presence of quenched disorder and a magnetic field. In the disorder-free limit, the Wigner crystal Hall angle is independent of crystal velocity, but when disorder is present, we find that Hall angle starts near zero at the depinning threshold and increases linearly with increasing drive before reaching a saturation close to the disorder free value at the highest drives. The drive dependence is the result of a side jump effect produced when the charges move over pinning sites. The magnitude of the side jump is reduced at the higher velocities. The drive dependent Hall angle is robust for a wide range of disorder parameters and should be a generic feature of classical charges driven in the presence of quenched disorder and a magnetic field.
description: 6 pages, 4 postscript figures
Vortex Dynamics, Pinning, and Magic Angles on Moiré Patterns
Creators: name: Li, Wenzhao
name: Reichhardt, C. J. O.
name: Jankó, B.
name: Reichhardt, C.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We examine pinning and dynamics of Abrikosov vortices interacting with pinning centers placed in a moiré pattern for varied moiré lattice angles. We find a series of magic angles at which the critical current shows a pronounced dip corresponding to lattices in which the vortices can flow along quasi-one-dimensional channels. At these magic angles, the vortices move with a finite Hall angle. Additionally, for some lattice angles there are peaks in the critical current produced when the substrate has a quasiperiodic character that strongly reduces the vortex channeling. Our results should be general to a broad class of particle-like assemblies moving on moiré patterns.
description: 5 pages, 5 figures
Vortex Ordering and Dynamics on Santa Fe Artificial Ice Pinning Arrays
Creators: name: Li, Wenzhao
name: Reichhardt, C. J. O.
name: Jankó, B.
name: Reichhardt, C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We numerically examine the ordering, pinning and flow of superconducting vortices interacting with a Santa Fe artificial ice pinning array. We find that as a function of magnetic field and pinning density, a wide variety of vortex states occur, including ice rule obeying states and labyrinthine patterns. In contrast to square pinning arrays, we find no sharp peaks in the critical current due to the inherent frustration effect imposed by the Santa Fe ice geometry; however, there are some smoothed peaks when the number of vortices matches the number of pinning sites. For some fillings, the Santa Fe array exhibits stronger pinning than the square array due to the suppression of one-dimensional flow channels when the vortex motion in the Santa Fe lattice occurs through the formation of both longitudinal and transverse flow channels.
description: 4 pages, 4 figures
DC Semidefinite Programming and Cone Constrained DC Optimization: Theory and Local Search Methods
Creators: name: Dolgopolik, M. V.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 90C22, 90C26

description: In this paper, we study possible extensions of the main ideas and methods of constrained DC optimization to the case of nonlinear semidefinite programming problems and more general nonlinear and nonsmooth cone constrained optimization problems.
 In the first part of the paper, we analyse two different approaches to the definition of DC matrix-valued functions (namely, order-theoretic and componentwise), study some properties of convex and DC matrix-valued mappings and demonstrate how to compute DC decompositions of some nonlinear semidefinite constraints appearing in applications. We also compute a DC decomposition of the maximal eigenvalue of a DC matrix-valued function. This DC decomposition can be used to reformulate DC semidefinite constraints as DC inequality constrains. Finally, we study local optimality conditions for general cone constrained DC optimization problems.
 The second part of the paper is devoted to a detailed convergence analysis of two extensions of the well-known DCA method for solving DC (Difference of Convex functions) optimization problems to the case of general cone constrained DC optimization problems. We study the global convergence of the DCA for cone constrained problems and present a comprehensive analysis of a version of the DCA utilizing exact penalty functions. In particular, we study the exactness property of the penalized convex subproblems and provide two types of sufficient conditions for the convergence of the exact penalty method to a feasible and critical point of a cone constrained DC optimization problem from an infeasible starting point. In the numerical section of this work, the exact penalty DCA is applied to the problem of computing compressed modes for variational problems and the sphere packing problem on Grassmannian.
description: In the second version of the paper, typos and a number of small mistakes were corrected and a section containing results of numerical experiments was added
Codifferentials and Quasidifferentials of the Expectation of Nonsmooth Random Integrands and Two-Stage Stochastic Programming
Creators: name: Dolgopolik, M. V.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optimization and Control (math.OC)
subject: Probability (math.PR)
subject: FOS: Mathematics

description: This work is devoted to an analysis of exact penalty functions and optimality conditions for nonsmooth two-stage stochastic programming problems. To this end, we first study the co-/quasi-differentiability of the expectation of nonsmooth random integrands and obtain explicit formulae for its co- and quasidifferential under some natural assumptions on the integrand. Then we analyse exact penalty functions for a variational reformulation of two-stage stochastic programming problems and obtain sufficient conditions for the global exactness of these functions with two different penalty terms. In the end of the paper, we combine our results on the co-/quasi-differentiability of the expectation of nonsmooth random integrands and exact penalty functions to derive optimality conditions for nonsmooth two-stage stochastic programming problems in terms of codifferentials.
Statics and Dynamics of Skyrmions Interacting with Pinning: A Review
Creators: name: Reichhardt, C.
name: Reichhardt, C. J. O.
name: Milosevic, M. V.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Magnetic skyrmions are topologically stable nanoscale particle-like objects that were discovered in 2009. Since that time, intense research interest has led to the identification of numerous compounds that support skyrmions over a range of conditions spanning cryogenic to room temperatures. Skyrmions can be set into motion under various types of driving, and the combination of their size, stability, and dynamics makes them ideal candidates for numerous applications. Skyrmions represent a new class of system in which the energy scales of the skyrmion-skyrmion interactions, sample disorder, temperature, and drive can compete. A growing body of work indicates that the static and dynamic states of skyrmions can be influenced strongly by pinning or disorder in the sample; thus, an understanding of such effects is essential for the eventual use of skyrmions in applications. In this article we review the current state of knowledge regarding individual skyrmions and skyrmion assemblies interacting with quenched disorder or pinning. We outline the microscopic mechanisms for skyrmion pinning, including the repulsive and attractive interactions that can arise from impurities, grain boundaries, or nanostructures. This is followed by descriptions of depinning phenomena, sliding states over disorder, the effect of pinning on the skyrmion Hall angle, the competition between thermal and pinning effects, the control of skyrmion motion using ordered potential landscapes such as one- or two-dimensional periodic asymmetric substrates, the creation of skyrmion diodes, and skyrmion ratchet effects. We highlight the distinctions arising from internal modes and the strong gyroscopic or Magnus forces that cause the dynamical states of skyrmions to differ from those of other systems with pinning. We also discuss future directions and open questions related to the pinning and dynamics in skyrmion systems.
description: 66 pages, 71 figures
title: Forschungsdatenzentrum "German Microdata Lab": Service für amtliche Mikrodaten ; Jahresbericht 2019
Creators: name: Dragon, Iris
Publisher: name: SSOAR -   GESIS Leibniz Institute for the Social Sciences
Year: 2021
Subjects: subject: 10105 Methods and Techniques of Data Collection and Data Analysis, Statistical Methods, Computer Methods
subject: microcensus
subject: data access
subject: data documentation
subject: official statistics
subject: information system
subject: data quality
subject: data bank
subject: data preparation
subject: empirical social research

description: Der Bericht dokumentiert die Arbeiten des German Microdata Lab (GML) bei GESIS für das Jahr 2019. Das GML ist eine Serviceeinrichtung für die Sozialforschung und vertritt deren Interessen gegenüber der amtlichen Statistik. Das GML ist unabhängig von Statistischen Ämtern und anderen Datenproduzenten und wirkt als Schnittstelle zwischen empirischer Sozialforschung und amtlicher Statistik.
description: This report documents the work of the German Microdata Lab (GML) at GESIS for the year 2019. The GML is a service facility for social scientists and represents their interests in relation to the official statistics. The German Microdata Lab is independent from statistical offices and other data producers and acts as an interface between empirical social research and official statistics.
description: GESIS Papers, 2021/01, 50 S.
Minimum Spanning Tree Cycle Intersection Problem
Creators: name: Dubinsky, Manuel
name: Massri, César
name: Taubin, Gabriel
Publisher: name: arXiv
Year: 2021
Subjects: subject: Discrete Mathematics (cs.DM)
subject: Combinatorics (math.CO)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Consider a connected graph $G$ and let $T$ be a spanning tree of $G$. Every edge $e \in G-T$ induces a cycle in $T \cup \{e\}$. The intersection of two distinct such cycles is the set of edges of $T$ that belong to both cycles. We consider the problem of finding a spanning tree that has the least number of such non-empty intersections.
title: Internet aus dem Weltraum
title: wie neuartige Satellitenverbindungen die globale Internet-Governance verändern können
titleType: Subtitle
Creators: name: Voelsen, Daniel
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP-Studie, 2/2021
title: Open-Skies-Vertrag in Gefahr
title: nach dem Austritt der USA will nun auch Russland folgen
titleType: Subtitle
Creators: name: Richter, Wolfgang
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP-Aktuell, 10/2021
title: Standing on our own feet?
title: opportunities and risks of European self-defence
titleType: Subtitle
Creators: name: Lübkemeier, Eckhard
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP Research Paper, 1/2021
Clogging, Dynamics and Reentrant Fluid for Active Matter on Periodic Substrates
Creators: name: Reichhardt, C.
name: Reichhardt, C. J. O.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We examine the collective states of run-and-tumble active matter disks driven over a periodic obstacle array. When the drive is applied along a symmetry direction of the array, we find a clog-free uniform liquid state for low activity, while at higher activity, the density becomes increasingly heterogeneous and an active clogged state emerges in which the mobility is strongly reduced. For driving along non-symmetry or incommensurate directions, there are two different clogging behaviors consisting of a drive dependent clogged state in the low activity thermal limit and a drive independent clogged state at high activity. These regimes are separated by a uniform flowing liquid at intermediate activity. There is a critical activity level above which the thermal clogged state does not occur, as well as an optimal activity level that maximizes the disk mobility. Thermal clogged states are dependent on the driving direction while active clogged states are not. In the low activity regime, diluting the obstacles produces a monotonic increase in the mobility; however, for large activities, the mobility is more robust against obstacle dilution. We also examine the velocity-force curves for driving along non-symmetry directions, and find that they are linear when the activity is low or intermediate, but become nonlinear at high activity and show behavior similar to that found for the plastic depinning of solids. At higher drives the active clustering is lost. For low activity we also find a reentrant fluid phase, where the system transitions from a high mobility fluid at low drives to a clogged state at higher drives and then back into another fluid phase at very high drives. We map the regions in which the thermally clogged, partially clogged, active uniform fluid, clustered fluid, active clogged, and directionally locked states occur as a function of disk density, drift force, and activity.
description: 15 pages, 22 figures
title: Argentinien - politische Ruhe im sozioökonomischen Unwetter
title: ein Jahr nach der Rückkehr des Peronismus an die Macht
titleType: Subtitle
Creators: name: Zilla, Claudia
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP-Aktuell, 11/2021
title: Psychometric Properties of the “Quality of Instruction” Scale in Starting Cohort 3
Creators: name: Hawrot, Anna
Publisher: name: LIfBi Leibniz Institute for Educational Trajectories
Year: 2021
Subjects: subject: psychometric properties
subject: quality of instruction
subject: Three Basic Dimensions

description: This paper presents information on the source, theoretical background, and psychometric
properties of the “Quality of instruction” scale used in Waves 3 and 5 of Starting Cohort 3. The scale measures student perceptions of teaching quality in their school. We ran an item-level analysis and checked the scale’s reliability, discriminant validity, construct validity, and measurement invariance over the waves. The items had moderate to high discriminatory power. The analyses confirmed the scale’s discriminant validity and its expected three-factor structure, but also revealed moderate to strong correlations between the factors. The internal consistencies of the subscales ranged from marginally acceptable for Classroom Management and Cognitive Activation to satisfactory for Student Support. The scale was metrically invariant across the two waves of the study. Overall, the test showed acceptable to good psychometric properties, depending on the aspect.
description: NEPS Survey Papers, No. 81 (2021)
title: Psychometric Properties of the “Teaching Quality” Scale for Teachers in Starting Cohorts 2, 3, and 4
Creators: name: Hawrot, Anna
Publisher: name: LIfBi Leibniz Institute for Educational Trajectories
Year: 2021
Subjects: subject: teaching quality
subject: teachers
subject: psychometric properties
subject: Three Basic Dimensions

description: This paper presents information on the source, theoretical background, and psychometric properties of the “Teaching quality” scale used in Wave 2 of Starting Cohort 2, Waves 2 and 7 of Starting Cohort 3, and Wave 3 of Starting Cohort 4. The scale measures teacher perceptions of the quality of their own instruction. We ran an item-level analysis and checked the scale’s reliability and internal structure. The items had low to moderate discriminatory power and the internal consistencies of the subscales were low. The analyses did not confirm the expected three-factor structure of the scale. A two-factor structure emerged, but it was not fully consistent across Waves and Starting Cohorts. Overall, the test needs major refinements before it can be used as a measure of teaching qualit.
description: NEPS Survey Papers, No. 82 (2021)
title: EU-Strategie zur Cybersicherheit
title: Desiderat Cyberdiplomatie
titleType: Subtitle
Creators: name: Bendiek, Annegret
name: Kettemann, Matthias C.
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP-Aktuell, 12/2021
title: Zurück in die Zukunft?
title: die internationale Klimapolitik 2021 : neue Konstellationen für die europäische Klimadiplomatie
titleType: Subtitle
Creators: name: Dröge, Susanne
name: Schrader, Tessa-Sophie
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP-Aktuell, 13/2021
title: Social cohesion after armed conflict: a literature review
Creators: name: Fiedler, Charlotte
name: Christopher, Rohles
Publisher: name: German Development Institute / Deutsches Institut für Entwicklungspolitik (DIE)
publisherIdentifier: https://ror.org/01t3zke88
publisherIdentifierScheme: ROR
Year: 2021
Subjects: subject: social cohesion
subject: armed conflict
subject: peacebuilding
subject: trust
subject: cooperation
subject: identity
subject: literature review

description: How does armed conflict affect social cohesion, that is, the social fabric of societies? This question is central if we want to understand better why some countries experience repeated cycles of violence. It is also a crucial question for the design of peacebuilding interventions. In recent years, considerable scientific work has been put into studying the social legacies of armed conflict. This literature review brings these academic studies together in a novel way.

 In this discussion paper we conduct an extensive review of the empirical academic literature on how armed conflict affects social cohesion. We take a holistic perspective and analyse each of the three constituent elements of social cohesion – trust, cooperation and identity – in detail and along both a vertical (state-society relations) and a horizontal (interpersonal and intergroup relations) dimension. Regarding conflict, the focus lies on intrastate conflict and civil war, but the review also includes the few studies that focus on armed conflict between states or groups (interstate and non-state conflict). Overall, this review brings together insights from 39 published, peer-reviewed, empirical studies, most of which analyse the effects of conflict based on comprehensive survey data or behavioural experiments. Strengths and shortcomings are discussed and future avenues for research are identified.

 Contrary to the initial optimism of the potentially positive legacies of armed conflict expressed by some scholars, our main finding holds that the literature by now mainly points towards such conflict harming social cohesion. Most clearly, there is quite a large body of literature showing that social trust is negatively affected by experience of violence. Research on political trust and social identities is still nascent but currently also points towards negative effects. The literature on cooperation is more mixed with studies finding both support for an increase or a decrease in cooperative behaviour. However, several (and particularly newer) studies demonstrate that an increase in cooperation can often be explained by prosocial behaviour towards the in-group but not the out-group, calling into question whether this should be interpreted positively for social cohesion overall. Political participation does, however, seem to be one aspect of social cohesion in which effects of the “post-traumatic growth” mechanism can indeed be traced in several contexts.
description: Discussion Paper, 7/2021
title: Social cohesion after armed conflict: a literature review
Creators: name: Fiedler, Charlotte
name: Rohles, Christopher
Publisher: name: German Development Institute / Deutsches Institut für Entwicklungspolitik (DIE)
publisherIdentifier: https://ror.org/01t3zke88
publisherIdentifierScheme: ROR
Year: 2021
Subjects: subject: social cohesion
subject: armed conflict
subject: peacebuilding
subject: trust
subject: cooperation
subject: identity
subject: literature review

description: How does armed conflict affect social cohesion, that is, the social fabric of societies? This question is central if we want to understand better why some countries experience repeated cycles of violence. It is also a crucial question for the design of peacebuilding interventions. In recent years, considerable scientific work has been put into studying the social legacies of armed conflict. This literature review brings these academic studies together in a novel way.

 In this discussion paper we conduct an extensive review of the empirical academic literature on how armed conflict affects social cohesion. We take a holistic perspective and analyse each of the three constituent elements of social cohesion – trust, cooperation and identity – in detail and along both a vertical (state-society relations) and a horizontal (interpersonal and intergroup relations) dimension. Regarding conflict, the focus lies on intrastate conflict and civil war, but the review also includes the few studies that focus on armed conflict between states or groups (interstate and non-state conflict). Overall, this review brings together insights from 39 published, peer-reviewed, empirical studies, most of which analyse the effects of conflict based on comprehensive survey data or behavioural experiments. Strengths and shortcomings are discussed and future avenues for research are identified.

 Contrary to the initial optimism of the potentially positive legacies of armed conflict expressed by some scholars, our main finding holds that the literature by now mainly points towards such conflict harming social cohesion. Most clearly, there is quite a large body of literature showing that social trust is negatively affected by experience of violence. Research on political trust and social identities is still nascent but currently also points towards negative effects. The literature on cooperation is more mixed with studies finding both support for an increase or a decrease in cooperative behaviour. However, several (and particularly newer) studies demonstrate that an increase in cooperation can often be explained by prosocial behaviour towards the in-group but not the out-group, calling into question whether this should be interpreted positively for social cohesion overall. Political participation does, however, seem to be one aspect of social cohesion in which effects of the “post-traumatic growth” mechanism can indeed be traced in several contexts.
description: Discussion Paper, 7/2021
title: Chamelaucium :
title: Principes directeurs pour la conduite de l’examen de la distinction, de l’homogénéité et de la stabilité.
titleType: Subtitle
Creators: name: International Union For The Protection Of New Varieties Of Plants,
Publisher: name: International Union for the Protection of New Varieties of Plants,
Year: 0
Subjects: Group identity.
New Varieties of Plants
Waxflower

description: Ces principes directeurs (“principes directeurs d’examen”) visent à approfondir les principes énoncés dans l’introduction générale (document TG/1/3) et dans les documents TGP qui s’y rapportent afin de donner des indications concrètes détaillées pour l’harmonisation de l’examen de la distinction, de l’homogénéité et de la stabilité (DHS) et, en particulier, à identifier des caractères convenant à l’examen DHS et à la production de descriptions variétales harmonisées.
title: Navigating through an external agenda and internal preferences: Ghana’s National Migration Policy
Creators: name: Segadlo, Nadine
Publisher: name: German Development Institute / Deutsches Institut für Entwicklungspolitik (DIE)
publisherIdentifier: https://ror.org/01t3zke88
publisherIdentifierScheme: ROR
Year: 2021
Subjects: subject: migration
subject: Ghana
subject: Africa
subject: European Union

description: In the context of international migration from African countries to Europe, the EU widely applies the strategy of curbing irregular migration. EU efforts focus on combating the root causes of migration and flight as well as achieving African compliance on return and re-admission. This approach ignores the interests of the countries of origin. It also undermines what countries of origin do to deal with migration in their own states. In West Africa, the regional organisation ECOWAS strongly promotes migration management, and introduced the 2008 ECOWAS Common Approach on Migration with guidelines for migration governance in the region. Ghana, as one of the first ECOWAS member states, adopted a National Migration Policy (NMP) in 2016. The country has a long history of migration, has experienced different migration trends and is affected by various streams of migration. As little is known about the country’s policy responses to migration, this study investigates migration policy-making in Ghana. It specifically examines the case of the NMP for Ghana and aims at uncovering stakeholder involvement in the policy-making process as well as its determinants. Guided by an analytical framework derived from theoretical considerations of the advocacy coalition framework, the interconnection of institutions, actors and ideas and an extensive literature review, the study uses a qualitative approach. The results are based on 14 weeks of field research in Ghana in which 40 experts were interviewed. Together with an analysis of a plethora of secondary data the study finds that when deciding to get involved in the policy-making process for the NMP for Ghana, stakeholders tend to be led by their interests and the resources they possess, as these are what their power is based on. The research further reveals that the NMP does not primarily address a perceived problem related to migration within Ghana, that is to say the internal migration flows from deprived to less deprived areas. Rather it largely pursues the interests of the EU, who is the main financer of the policy, to foster migration control. The results of the study therefore suggest that in the policy formulation process for Ghana’s NMP, internal interests were outweighed by the external agenda of the EU.
description: Discussion Paper, 8/2021
title: A restrained embrace
title: South Korea's response to Germany's Indo-Pacific strategey
titleType: Subtitle
Creators: name: Ballbach, Eric J.
name: Morazzini, Laura
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP Comment, 13/2021
title: Die Beendigung von Konsument-Marke-Beziehungen als Gegenstand eines studentischen Grounded-Theory-Forschungsprojekts
Creators: name: Geise, Wolfgang
name: Pömpner, Alexandra
Publisher: name: Digitale Wirtschaftsbildung (Digital Economic Education)
Year: 2021

description: Zeitschrift für ökonomische Bildung, 10002
title: Die neue Arktisstrategie der EU
title: maritime Sicherheit und geopolitische Akzente stärken
titleType: Subtitle
Creators: name: Paul, Michael
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP-Aktuell, 14/2021
title: Back to the future?
title: international climate policy in 2021 : new constellations for the EU's climate diplomacy
titleType: Subtitle
Creators: name: Dröge, Susanne
name: Schrader, Tessa-Sophie
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP Comment, 14/2021
title: Homomorphe Verschlüsselung und Europas Cloud
title: ein Baustein für Europas digitale Souveränität
titleType: Subtitle
Creators: name: Schulze, Matthias
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP-Aktuell, 15/2021
title: Die Drei-Meere-Initiative: wirtschaftliche Zusammenarbeit in geostrategischem Kontext
title: Deutschland sollte sein Engagement auch aus außenpolitischen Gründen verstärken
titleType: Subtitle
Creators: name: Lang, Kai-Olaf
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP-Aktuell, 16/2021
title: The pandemic and governance in the Maghreb
title: a moment of truth : the Covid-19 pandemic tests the sustainability of differenct governance approaches
titleType: Subtitle
Creators: name: Fakir, Intissar
name: Werenfels, Isabelle
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP Comment, 15/2021
Skyrmion Ratchet in Funnel Geometries
Creators: name: Souza, J. C. Bellizotti
name: Vizarim, N. P.
name: Reichhardt, C. J. O.
name: Reichhardt, C.
name: Venegas, P. A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Using a particle-based model, we simulate the behavior of a skyrmion under the influence of asymmetric funnel geometries and ac driving at zero temperature. We specifically investigate possibilities for controlling the skyrmion motion by harnessing a ratchet effect. Our results show that as the amplitude of a unidirectional ac drive is increased, the skyrmion can be set into motion along either the easy or hard direction of the funnel depending on the ac driving direction. When the ac drive is parallel to the funnel axis, the skyrmion flows in the easy direction and its average velocity is quantized. In contrast, when the ac drive is perpendicular to the funnel axis, a Magnus-induced ratchet effect occurs, and the skyrmion moves along the hard direction with a constant average velocity. For biharmonic ac driving of equal amplitude along both the parallel and perpendicular directions, we observe a reentrant pinning phase where the skyrmion ratchet vanishes. For asymmetric biharmonic ac drives, the skyrmion exhibits a combination of effects and can move in either the easy or hard direction depending on the configuration of the ac drives. These results indicate that it is possible to achieve controlled skyrmion motion using funnel geometries, and we discuss ways in which this could be harnessed to perform data transfer operations.
description: 11 pages, 19 figures
title: USA und Russland verlängern New Start
title: erst ein Folgevertrag wird künftig die strategische Stabilität sichern
titleType: Subtitle
Creators: name: Richter, Wolfgang
name: Stiftung Wissenschaft Und Politik
Publisher: name: Stiftung Wissenschaft und Politik (SWP), German Institute for International and Security Affairs
Year: 2021

description: SWP-Aktuell, 17/2021
Active extensile stress promotes 3D director orientations and flows
Creators: name: Nejad, Mehrana R.
name: Yeomans, Julia M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We use numerical simulations and linear stability analysis to study an active nematic layer where the director is allowed to point out of the plane. Our results highlight the difference between extensile and contractile systems. Contractile stress suppresses the flows perpendicular to the layer and favours in-plane orientations of the director. By contrast, extensile stress promotes instabilities that can turn the director out of the plane, leaving behind a population of distinct, in-plane regions that continually elongate and divide. This supports extensile forces as a mechanism for the initial stages of layer formation in living systems, and we show that a planar drop with extensile (contractile) activity grows into three dimensions (remains in two dimensions). The results also explain the propensity of disclination lines in three dimensional active nematics to be of twist-type in extensile or wedge-type in contractile materials.