Broadcasting multiple messages in the 1-in port model in optimal time

In the 1-in port model, every vertex of a synchronous network can receive at most one message in each time unit. We consider simultaneous broadcasting of multiple messages from the same source or from distinct sources in such networks with an additional restriction that every received message can be sent out to neighbors only in the next time unit and never to already informed vertex. We use a general concept of level-disjoint partitions developed for this scenario. Here we introduce a subgraph extension technique for efficient spreading information within this concept. Surprisingly, this approach with so called biwheels leads to simultaneous broadcasting of optimal number of messages on a wide class of graphs in optimal time. In particular, we provide tight results for bipartite tori, meshes, hypercubes, Knödel graphs, circulant graphs. We also propose several open problems and conjectures.     

Computing the distribution of sequential Hölder norms of the Brownian motion

ABSTRACT

In this article, we give explicit formulas and study practical computations for the distribution function of sequential Hölder norms of a Brownian motion and of a Brownian bridge. We also discuss some statistical applications in the detection of some short “epidemic” changes in a sample.     

Estimating the turning point of a bathtub-shaped failure distribution

The turning point of a hazard rate function is useful in assessing the hazard in the useful life phase and helps to determine and plan appropriate burn-in, maintenance, and repair policies and strategies. For many bathtub-shaped distributions, the turning point is unique, and the hazard varies little in the useful life phase. We investigate the performance of an empirical estimator for the turning point in the case of the modified Weibull distribution, a bathtub-shaped generalization of the Weibull distribution, that has been found to be useful in reliability engineering and other areas concerned with life-time data. We illustrate the theory by means of an example, and also conduct a simulation study to assess the performance of the estimator in practice.     

Perceptions of Migration and Diversity by Local Public Administrators

This article contributes to the recent debate on the perception of migration and diversity; it empirically examines whether public decision-makers and public administrators perceive migration and diversity as related or if they distinguish between them. It also seeks to identify the most important characteristics of respondents with positive attitudes to migration and diversity. The sample of the respondents covers Turkey, Greece, Hungary and Slovakia; those located on the “Balkan migration route” into Europe. Due to different experiences, respondents from countries with large-scale migration perceive migration and diversity differently from those in countries directly threatened by migration or countries without any direct impact of migration. Gender appears to be a statistically significant predictor in the need for high managerial skills to manage migration and diversity. Some size categories of municipalities where a respondent works appear to be statistically significant when ranking the local impacts and local economic benefits of migration.     

Changing Policy Environments in Europe and the Resilience of the Third Sector

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - In the article, we analyse the impact of changing policy environments on the development of the third sector in Europe....     

Flora of the tram tracks of Bratislava

Urban Ecosystems - Tram and railway tracks represent specific urban habitats, which host a specific type of flora. This study aims to compile the information about species composition of flora of...     

Monetary transmission: Are emerging market and low-income countries different?

We use the Christensen, Diebold, and Rudebusch (2011) representation of the yield curve to test the functioning of the interest rate transmission mechanism along the yield curve based on government paper in advanced, emerging market, and low-income countries. We find a robust link from the policy and short-term interbank rates to the longer-term bond yields in all countries. Two policy implications emerge. First, the presence of well-developed secondary markets does not seem to affect transmission of short term rates along the yield curve. Second, the strength of the transmission mechanism seems to be affected by the choice of the monetary regime and the level of development: advanced countries with a credible inflation targeting regime seem to have better-behaved yield curves than the countries with other monetary regimes.