A spatial model of the diffusion of mobile communications within the European Union

Innovation diffusion studies have been popular. However, usually the focus has been on two dimensions: Either the innovation's diffusion is studied on the micro level by examining the individual's adoption of an innovation, or on the macro-level by modelling the sigmoid diffusion curve. The third dimension of the diffusion of an innovation, spatial diffusion, has gained less attention. Spatial diffusion models mostly base on the effect of distance on an innovation's diffusion process. Generally, it is seen that the innovation is adopted later in places further away from the innovation centre, even though there are also other, mainly complementary, hypotheses about the diffusion of an innovation. One common approach for studying the spatial diffusion of an innovation, the spatial gravity model, builds on the distance of places in explaining the diffusion process. As the name of the model implies, the hypothesis is that the diffusion is due to different pulling forces of regions. In other words, regions adopt the innovation at a different time because of a different pulling force. In this study, a gravity-based spatial diffusion model is employed for studying the spatial diffusion of mobile communications within the European Union. The model considers the diffusion process on a national level, the adoption units being the member countries of the European Union. The countries' annual penetration rates of mobile subscribers are used as the diffusion data. Also, a variable testing the effect of the country's economic situation, measured by GDP per capita, on the spatial diffusion process is included in the model. Moreover, by extrapolating the model may be used for forecasting purposes, thus giving annual information about the diffusion of mobile communications in the near future. The European Union is a leader in the mobile field. This kind of first-mover position makes the studying of its diffusion process interesting: The results might give information, which could be utilized in controlling the followers' diffusion processes. Also, if there is a significant effect of the economic situation on the diffusion process, it comes with some interesting implications: If an economic recession is found to hinder the diffusion of mobile communications, is the current timing of launch of the third generation the optimal one, noting that the EU simultaneously faces a slowdown in growth? For judging this, the effect of different economic growth scenarios on the diffusion of mobile communications could be estimated, as the model might be used for forecasts.

Higgs Spin Determination in the WW channel and beyond

After the discovery of the 126 GeV resonance at the LHC, the determination of its features, including its spin, is a very important ongoing task. In order to distinguish the two most likely spin hypotheses, spin-0 or spin-2, we study the phenomenology of a light Higgs-like spin-2 resonance produced in different gluon-fusion and vector-boson-fusion processes at the LHC. Starting from an effective model for the interaction of a spin-2 particle with the SM gauge bosons, we calculate cross sections and differential distributions within the Monte Carlo program Vbfnlo. We find that with specific model parameters such a spin-2 resonance can mimic SM Higgs rates and transverse-momentum distributions in $\gamma \gamma$, $WW$ and $ZZ$ decays, whereas several distributions allow to separate spin-2 from spin-0, independently of the spin-2 model parameters.Comment: 14 pages, 7 figure

Space-Efficient Biconnected Components and Recognition of Outerplanar Graphs

We present space-efficient algorithms for computing cut vertices in a given graph with $n$ vertices and $m$ edges in linear time using $O(n+\min\{m,n\log \log n\})$ bits. With the same time and using $O(n+m)$ bits, we can compute the biconnected components of a graph. We use this result to show an algorithm for the recognition of (maximal) outerplanar graphs in $O(n\log \log n)$ time using $O(n)$ bits

Cavity-mediated electron-photon superconductivity

We investigate electron paring in a two-dimensional electron system mediated by vacuum fluctuations inside a nanoplasmonic terahertz cavity. We show that the structured cavity vacuum can induce long-range attractive interactions between current fluctuations which lead to pairing in generic materials with critical temperatures in the low-Kelvin regime for realistic parameters. The induced state is a pair density wave superconductor which can show a transition from a fully gapped to a partially gapped phase - akin to the pseudogap phase in high-$T_c$ superconductors. Our findings provide a promising tool for engineering intrinsic electron interactions in two-dimensional materials.Comment: 11 page

Telecommunications networks and services in Estonia. Lessons to other European countries.

Estonia has shown somewhat remarkable developments in the telecommunications – or more precisely, building up an efficient network of modern information and telecommunications technologies (ICTs) for the Information Society. This paper takes a look at the development of telecommunications infrastructure networks and services in Estonia. The study also evalu-ates what other countries could learn from Estonia. More specifically, by this study we at-tempt at answering whether Estonia is as successful as data suggests, what the factors behind this success are, and whether there are lessons to be learned for the entire European territory. The paper introduces to the development of the telecommunications infrastructure and ser-vices in Estonia, by presenting facts and figures, and comparing the progress of the country with that of other European countries. It also discusses the measures that have helped Estonia on the road to Information Society. The results show that in summary the success of Estonia seems to have been a result of three things: Proximity of Finland and Sweden, active regula-tion and relative early liberalization, and a competition and entrant friendly market environ-ment. The paper is an outgrowth of the ESPON (European Spatial Planning Observation Net-work) project 1.2.2 “Telecommunications Services and Networks: Territorial Trends and Ba-sic Supply of Infrastructure for Territorial Cohesion” (see: http://www.espon.lu).

Buchbesprechung: ERHARDT, W.; GÖTZ, E.; BÖDECKER, N. & SEYBOLD, S. (2008): Der große Zander. Enzyklopädie der Pflanzennamen

Der Band 1 „Familien und Gattungen“ führt in einleitenden Kapiteln in Fragen der botanischen Nomenklatur und der Nomenklatur von Kulturpflanzen ein und gibt eine systematische Übersicht über das Pflanzenreich (i. d. R. nach CRONQUIST 1988). Kernstück des 1. Bandes ist das Kapitel „Familien und Gattungen“ mit über 1.100 Seiten. In einleitenden Unterkapiteln werden botanische Fachbegriffe kurz erläutert und mit zahlreichen schematischen Abbildungen sehr anschaulich illustriert. Kurze Bestimmungsschlüssel erlauben eine schnelle Zuordnung systematisch wichtiger Merkmale zu Familien bzw. Gattungen

Konzeption für die Erarbeitung einer Flora Sachsen-Anhalts

Die in den letzten Jahrzehnten durch die Arbeitsgemeinschaft Herzynischer Floristen und das Institut für Geobotanik der Martin-Luther-Universität (MLU) Halle für das herzynische, bzw. das Gebiet der DDR koordinierte Erfassung der Gefäßpflanzen auf Basis von Meßtischblattquadranten (MTB-Q) fand mit der Fertigstellung des Verbreitungsatlasses der Farn- und Blütenpflanzen Ostdeutschlands (BENKERT et al. 1996) ihren Abschluß. Unser Anliegen ist es, die Kontinuität der floristischen Arbeit in Sachsen-Anhalt auch nach Fertigstellung des Verbreitungsatlasses aufrecht zu erhalten, bestehende Kartierungslücken zu schließen und die umfangreichen Detailkenntnisse regionaler Spezialisten zu Artvorkommen für die Naturschutzarbeit nutzbar zu machen

40A0* Subkontinentale peripannonische Gebüsche

Beschreibung und wertbestimmende Faktoren des Lebensraumtypes 40A0* Subkontinentale peripannonische Gebüsche nach Anhang I der Fauna-Flora-Habitatrichtlinie im Land Sachsen-Anhalt. Dieser umfasst niedrige sommergrüne Gebüsche (Prunion fruticosae) wärmebegünstigter Lagen kontinentaler und submediterraner Prägung auf basenreichen oder silikatischen Böden

Buchbesprechung: SHETEKAURI, S. & JACOBY, M. (2009): Gebirgsflora & Bäume des Kaukasus

Schwerpunkt des Buches ist die Beschreibung von etwa 970 Arten. Die meisten vorgestellten Arten sind mit Farbfotos illustriert. Von den etwa 6000 Pflanzenarten der kaukasischen Region wurden insbesondere auffällige zweikeimblättrige Stauden (keine Farne, Süßgräser, Sauergräser), Bäume und Sträucher mit Vorkommen über 1000 m NN dargestellt