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Partial, frustrated synchronization, and chimera-like states are expected to occur in Kuramoto-like models if the spectral dimension of the underlying graph is low: d s < 4. We provide numerical evidence that this really happens in the case of the high-voltage power grid of Europe (d s < 2), a large human connectome (KKI113) and in the case of the largest, exactly known brain network corresponding to the fruit-fly (FF) connectome (d s < 4), even though their graph dimensions are much higher, i.e., d g E U ≃ 2.6 (1) and d g F F ≃ 5.4 (1) , d g KKI 113 ≃ 3.4 (1). We provide local synchronization results of the first- and second-order (Shinomoto) Kuramoto models by numerical solutions on the FF and the European power-grid graphs, respectively, and show the emergence of chimera-like patterns on the graph community level as well as by the local order parameters. [ABSTRACT FROM AUTHOR]

We analyze whether financial integration leads to converging or diverging business cycles using a dynamic spatial model. Our model allows for contemporaneous spillovers of shocks to GDP growth between countries that are financially integrated and delivers a scalar measure of the spillover intensity at each point in time. For a financial network of ten European countries from 1996 to 2017, we find that the spillover effects are positive on average and much larger during periods of financial stress, pointing towards stronger business cycle synchronization. Dismantling GDP growth into value added growth of ten major industries, we observe that spillover intensities vary significantly. The findings are robust to a variety of alternative model specifications. [ABSTRACT FROM AUTHOR]

Already in the 1960s, Levenshtein and others studied error-correcting codes that protect against synchronization errors, such as symbol insertions and deletions. However, despite significant efforts, progress on designing such codes has been lagging until recently, particularly compared to the detailed understanding of error-correcting codes for symbol substitution or erasure errors. This paper surveys the recent progress in designing efficient error-correcting codes over finite alphabets that can correct a constant fraction of worst-case insertions and deletions. Most state-of-the-art results for such codes rely on synchronization strings, simple yet powerful pseudo-random objects that have proven to be very effective solutions for coping with synchronization errors in various settings. This survey also includes an overview of what is known about synchronization strings and discusses communication settings related to error-correcting codes in which synchronization strings have been applied. [ABSTRACT FROM AUTHOR]

The synchronization of the GDP growth cycles between countries have been discussed in the literature. The existence and dimensions of synchronization between the GDP growth cycles of the OECD countries are examined in this study. The existence of synchronization is revealed by estimating the time-varying (dynamic) conditional correlations used in measuring the level of synchronization in two stages by VAR-DCC-MGARCH methods in the study in which the period between 1961-2019 is analyzed. Unlike the literature, K-Means cluster analysis is applied to examine the differentiation of dynamic conditional correlations with respect to member countries. In addition, the effects of economic crises on dynamic conditional correlations are measured by panel data analysis by clusters. The findings showed that there is a synchronization among the member countries and the synchronization levels differ according to the countries. According to the synchronization levels, the member countries are determined to be divided into two clusters and it is observed that the countries in Europe and the Americas concentrated in one cluster. Finally, it is determined that the 1974 oil and 2009 global economic crises reduced the synchronization between the member countries while the 1963 European and 1997 Asian crises increased synchronization in the analysis period. It is observed that the effects of economic crises on synchronization are similar in direction but different in size by clusters. [ABSTRACT FROM AUTHOR]

This paper investigates a novel type of driver routing and scheduling problem motivated by a practical application in long-distance bus networks. A key difference from other crew scheduling problems is that drivers can be exchanged between buses at arbitrary intermediate stops en route such that our problem requires additional synchronization constraints. We present a mathematical model for this problem that leverages a time-expanded multi-digraph and derive bounds for the total number of required drivers. Moreover, we develop a destructive-bound-enhanced matheuristic that converges to provably optimal solutions and apply it to a real-world case study for Flixbus, one of Europe's leading coach companies. We demonstrate that our matheuristic outperforms a standalone MIP implementation in terms of solution quality and computational time and reduces the number of required drivers by up to 56% compared to approaches currently used in practice. Our solution approach provides feasible solutions for all instances within seconds and solves instances with up to 390 locations and 70 requests optimally with an average computational time under 210 sec. We further study the impact of driver exchanges on the total driver count and show that allowing for such exchanges leads to average savings of 42.69%. • We introduce a novel driver routing and scheduling problem with driver exchanges. • We formulate a MILP based on a time-expanded directed multi-graph. • We propose a matheuristic enriched by a destructive bound improvement procedure. • We demonstrate the performance of our algorithm in a real-world case study. • We provide managerial insights on the impact of driver swaps at intermediate stops. [ABSTRACT FROM AUTHOR]

Globalization and business cycles are equally elusive economic phenomena; hence they represent a continuous research possibility and a source of possible inquiries due to their complex nature. The aim of the paper is to explain the synchronization of business cycles using the relationship between the growth rate of the GDP and FDI, considered as percentage of the GDP. The results show that there is no unique European business cycle, but two cores between which countries migrate and stress out the importance of the FDI channel in business cycle transmission. The future research directions will employ fuzzy cluster techniques, used on a larger sample. [ABSTRACT FROM AUTHOR]

Business cycle synchronization represents a condition for the successful implementation of the common monetary policy within the Economic and Monetary Union. There is a tight relation between business cycle synchronization and the economic convergence of the Member States of the Monetary Union. Investigating the specialized literature, this study analyses below the factors which influence the synchronization of the economic fluctuations of the economies in the Euro area. A second objective of this study is represented by the pointing out of the evolution of the synchronization process of the business cycle after the adoption of the euro, in the euro area countries by reference to the empiric evidence. The hypothesis of the study states that the introduction of the unique currency in 1999 resulted into the increase of the synchronization degree of the business cycle. [ABSTRACT FROM AUTHOR]

The creation of the new European Higher Education Area (EHEA), with the corresponding changes in the structure and content of university degrees, offers a great opportunity to review learning methodologies. This paper investigates the effect on students of moving from a traditional learning process, based on lectures and laboratory work, to an approach closer to continuous evaluation. To this end, various types of weekly assessments were included in a Distributed Information Systems course; these assessments and the teacher's feedback were both intended to increase students' participation in the learning process. Data for seven academic years have been compiled, representing a total of more than 750 students. Analysis of the results established that most students preferred to participate in the course following the new methodology. Although both the pass rate and the final students' grades improved, the percentage of students dropping out of the course increased slightly. The impact of carrying out the proposed assessments was the same, regardless of gender and whether the student had taken this course before. In addition, compulsory attendance at office hours did not impact the degree of student participation in the new methodology. Finally, it was found that the greater (more continuous) effort demanded by the new methodology had an effect on the teacher's evaluation, whose scores were slightly lower with the new methodology, even though the students' performed better. [ABSTRACT FROM AUTHOR]

Synchronization of growth rates are an important feature of international business cycles, particularly in relation to regional integration projects such as the single currency in Europe. Synchronization of growth rates clearly enhances the effectiveness of European Central Bank monetary policy, ensuring that policy changes are attuned to the dynamics of growth and business cycles in the majority of member states. In this paper, a dissimilarity metric is constructed by measuring the topological differences between the GDP growth patterns in recurrence plots for individual countries. The results show that synchronization of growth rates were higher among the euro area member states during the second half of the 1980s and from 1997 to roughly 2002. Apart from these two time periods, euro area member states do not appear to be more synchronized than a group of major international countries, suggesting that apart from specific times when European integration initiatives were being implemented, globalization was likely the dominant factor behind international business cycle synchronization. [ABSTRACT FROM AUTHOR]

In what manner is political time institutionalized in the political system of the EU? This article advances five propositions on political time in the EU and highlights their implications for the workings of the EU. The propositions stress: (i) the absence of a dominant EU political cycle, which creates problems of mobilization and synchronization, but also allows for temporal plurality; (ii) an emphasis on linear political time, associated with ongoingness and open-endedness, as opposed to cyclical political time, which favours discontinuity in institutional practices and policies; (iii) intensive bargaining over time-setting, which encourages governing by timetable; (iv) the sensitivity of EU political time to member state influence, on the one hand, and (v) the Europeanization of political time in the member states, on the other. The balances struck in the temporal constitution of the EU are critical to its future. [ABSTRACT FROM AUTHOR]

Reproduction is generally controlled by important temporal constraints involving complex adaptive mechanisms. Birds, in temperate zones, present marked breeding seasonality as well as marked daily organization of reproductive behavior, especially laying. Intra-specific variability and determinants of this pattern have been investigated mainly in domestic non-passerine birds. The present study analyzed the daily temporal organization of laying in a free-living species, the European starling, Sturnus vulgaris. Breeding in a starling colony was monitored for five consecutive years using a non-invasive method (infrared video camera) to precisely estimate laying times. European starlings present a marked daily laying rhythm, ovipositions occurring only during a morning species-specific temporal window. Inside this laying window, time intervals between successive eggs varied greatly among females. Contrary to many species, the light/dark cycle did not appear to control laying time in European starlings, but daily variations of the ultraviolet composition of the solar spectrum appeared to be a possible Zeitgeber of this behavior. [ABSTRACT FROM AUTHOR]

The precise date of the Laacher See eruption (LSE), central Europe's largest Late Pleistocene volcanic event that occurred around 13,000 years ago, is still unknown. Here, we outline the potential of combined high-resolution dendrochronological, wood anatomical and radiocarbon (14C) measurements, to refine the age of this major Plinian eruption. Based on excavated, subfossil trees that were killed during the explosive LSE and buried under its pyroclastic deposits, we describe how a firm date of the eruption might be achieved, and how the resulting temporal precision would further advance our understanding of the environmental and societal impacts of this event. Moreover, we discuss the relevance of an accurate LSE date for improving the synchronization of European terrestrial and lacustrine Late Glacial to Holocene archives. • Previous age estimates of the Laacher See Eruptions (LSE) around 12,900 years are still diverging and imprecise. • The combination of dendrochronology, wood anatomy, and 14C measurements holds the potential to establish a precise LSE date. • An absolute calendric date of the LSE would improve the synchronization of European Late Glacial to Holocene archives. [ABSTRACT FROM AUTHOR]