Search for relativistic magnetic monopoles with the AMANDA detector

Diese Arbeit beschreibt die Suche nach relativistischen magnetischen Monopolen mit dem AMANDA Detektor. Die Methoden der Simulation und der Untergrundseparation werden erläutert. Keine Spuren mit der Signatur eines magnetischen Monopols wurden gefunden. Das sich ergebende Flusslimit von 0.61x10^-16 1/(cm^2 sr s) für Monopole, die sich nahe der Lichtgeschwindigkeit bewegen, liegt um einen Faktor 3-4 besser als die Ergebnisse vergleichbarer Untergrundexperimente und einen Faktor 16 unterhalb der Grenze, die aus der beobachteten Stabilität der galaktischen Magnetfelder liegt.This thesis describes the search for relativistic magnetic monopoles with the AMANDA detector. The methods of their simulation and their separation from the background are given. No tracks with the signature of a magnetic monopoles are found, resulting in an upper limit on the flux of 0.61x10^-16 1/(cm^2 sr s) for monopoles with velocities close to the speed of light. This is better by a factor of 3-4 compared to results from other underground detectors and a factor of 16 below the limit derived from the observed stability of the galactic magnetic fields

Eine sportökonomische Analyse von E-Sport mit Blick auf Marktstruktur und Competitive Balance

In den vergangenen Jahrzehnten ist der Markt rund um E-Sport schnell gewachsen. Durch Turniere mit immer höheren Zuschauer- und Umsatzzahlen hat der E-Sport in vielen verschiedenen Interessensgebieten den klassischen Sport bereits überholt. Dennoch gibt es kaum sportökonomische Literatur, die den E-Sports untersucht. Um diese Lücke zu schließen, wird zunächst untersucht, ob eine ausreichende Vergleichbarkeit zwischen E-Sport und klassischen Sportarten besteht. Dazu wird geprüft, ob sich Marktstrukturen des klassischen Sports auch im E-Sport finden lassen. Ein besonderes Augenmerk wird dabei auf die Struktur mehrseitiger Märkte gelegt. Diese Marktstruktur findet sich sowohl im klassischen Sport als auch im E-Sport. Charakteristisch für den E-Sport ist, dass die gespielten Titel im Besitz von Unternehmen sind. Dies steht im Gegensatz zu den Sportarten des klassischen Sports. Unternehmen im E-Sports Ökosystem sind in der Lage, mit verschiedenen Strategien, wie z.B. Integrationsstrategien, ihre Position auf dem Markt zu stärken. Typischerweise lassen sich zwei Stufen der vertikalen Integration zwischen Spieleentwickler, Spieleverleger und Turnierveranstalter ausmachen. Abhängig von den Integrationsstufen haben die Unternehmen einen größeren Einfluss auf den Verlauf des Turniers. Deshalb wird im nächsten Schritt geprüft, inwieweit der sportliche Wettkampf der Turniere durch den wirtschaftlichen Wettbewerb der beteiligten Unternehmen beeinflusst wird. Die Competitive Balance der Turniere dient dabei als Indikator. Durch den Vergleich von zwei Turnieren mit verschiedenen Integrationsstufen der involvierten Unternehmen lässt sich der Einfluss der eingesetzten Strategien erkennen. In Strukturen, in denen mehrere getrennte Unternehmen einen Einfluss auf ein Turnier haben, wird die Competitive Balance erhöht.In the past decades, the esports market has grown rapidly. Due to tournaments with ever increasing spectators and revenue figures, esports has already overtaken ordinary sports in many different fields of interest. Nevertheless, there is hardly any literature on sports economics that examines the esports market. To close this gap, it is first examined whether a sufficient comparability between esports and sports exists at all. For this purpose, it is determined whether market structures of ordinary sports can also be found in esports. A special attention is paid to the structures of multisided markets. This market structure is found in ordinary sports as well as esports. Characteristic for esports is that the titles played are owned by companies. This contrasts with those in ordinary sports. Companies in the esports ecosystem are able to use different strategies, such as integration strategies, to strengthen their position on the market. Typically, two stages of vertical integration between game developer, game publisher and tournament organizer can be identified. Depending on the stages of integration, the companies have an increased influence on the course of the tournament. Therefore, the next step is to test to what extent the sporting competition of the tournaments is influenced by economic competition of the involved companies. The competitive balance of the tournaments serves as an indicator. Comparing two tournaments with different market structures, the influence of the strategies used can be identified. In structures where more separate companies have an influence on a tournament, the competitive balance is increased

Micro Housing: No Contribution to Affordable Housing – a Berlin Case Study

The limited body of research on micro housing, which refers to small-scale housing units for single-person households, often associates this with housing affordability. In this study, we analyse the affordability of micro housing based on housing advertisements using Berlin as case study area. Therefore, we focus on different target groups of micro housing named by industry-driven research. On the one hand, we argue that the relevance of some of these groups for housing affordability from anurban development planning perspective is questionable. On the other hand, the results indicate that micro units are hardly affordable for target groups such as students, who are often affected by housing affordability problems. Our study illustrates that for Berlin there is a substantial mismatch between the potential contribution postulated in literature and the actual contribution of micro units to affordable housin

To build or not to build -- A queueing-based approach to timetable independent railway junction infrastructure dimensioning

Many infrastructure managers have the goal to increase the capacity of their railway infrastructure due to an increasing demand. While methods for performance calculations of railway line infrastructure are already well established, the determination of railway junction capacity remains a challenge. This work utilizes the concept of queueing theory to develop a method for the capacity calculation of railway junctions, solely depending on their infrastructure layout along with arrival and service rates. The implementation of the introduced approach is based on advanced model-checking techniques. It can be used to decide which infrastructure layout to build, i.e. whether an overpass for the analysed railway junction is needed. The developed method hence addresses the need for fast and reliable timetable independent junction evaluation in the long-term railway capacity calculation landscape.Comment: Research data has been published at doi:10.5281/zenodo.836346

Критика антикоммунистических взглядов на соотношение классового и общечеловеческого в воспитании

This work introduces a mathematical model for laser cutting which involves two coupled nonlinear partial differential equations. The model will be investigated by linear stability analysis to study the occurence of ripple formations at a cutting surface. We define a measurement for the roughness of the cutting surface and give a method for minimizing the roughness with respect to process parameters. A numerical solution of this nonlinear optimization problem will be presented and compared with the results of the linear stability analysis

Questionnaire design decisions when transitioning from an interviewer-administered to a self-administered online mode (Version 1.0)

Large-scale surveys are increasingly moving from (face-to-face or telephone-based) interviewer-administered to self-administered online modes. To ensure high measurement quality and maximum comparability and equivalence between the source questionnaire and its adaptation - across modes as well as across survey waves - various aspects of question design must be considered and several decisions need to be made concerning question presentation and wording. This survey guideline summarizes good practices on how to transition questionnaires from interviewer- to self-administered web surveys and gives recommendations and examples for major adaptation issues as well as general questionnaire design elements relevant to web surveys. In this context, we focus on the switch from an interviewer-based to an online mode (although mixed-mode designs are also conceivable).Groß angelegte Studien werden zunehmend von interviewerbasierten (persönlichen oder telefonischen) Befragungen auf selbstverwaltete Onlineerhebungen umgestellt. Um eine hohe Datenqualität und ein Höchstmaß an Vergleichbarkeit und Äquivalenz zwischen dem Ausgangsfragebogen und seiner Adaptation - sowohl über verschiedenen Modi als auch Erhebungswellen hinwe - zu gewährleisten, müssen verschiedene Aspekte des Fragebogendesigns berücksichtigt und eine Reihe von Entscheidungen in Bezug auf die Präsentation und Formulierung von Fragen getroffen werden. Dieser Erhebungsleitfaden fasst bewährte Methoden zur Umwandlung der Fragebögen von interviewgestützten zu selbstgestützten Onlineerhebungen zusammen und gibt Empfehlungen und Beispiele für wichtige Anpassungsfragen sowie zu allgemeinen Gestaltungselementen von Fragebögen, die für Onlineumfragen relevant sind. In diesem Zusammenhang konzentrieren wir uns auf den Wechsel von einem interviewergestützten zu einem Onlinemodus (obwohl auch gemischte Modi denkbar sind)

Принципы оптимизации параметров и режимов регулирования электродвигателей при переменной частоте тока

Излагаются основные принципы оптимизации параметров и режимов регулирования электродвигателей при переменной частоте тока. Математически формулируются задачи оптимизации. Показано, что оптимальные параметры и режимы регулирования двигателей нужно искать, исходя из заданного диапазона частот. Предлагаются новые методы оптимизации параметров и режимов регулирования двигателей, предназначенных для работы при переменной частоте

Influence of Different Prioritization Approaches of Maintenance and Replacement Measures on Station Infrastructure Quality

This paper presents a model that establishes a relationship between the financial resources allocated to maintain and replace railway station infrastructure assets and the resulting infrastructure quality. Until now, there has been no known relationship between quality and financial resources, making targeted planning for railway stations and the control of financial resources challenging. This model aims to predict infrastructure quality by analyzing the age-related degradation of infrastructure assets using historical data. The effects of maintenance and replacement measures are implemented in the model to map quality-improving measures. This allows for the comparison and analysis of different budget allocation scenarios on different assets, with different approaches for prioritizing replacement and maintenance measures. In this paper, the influence of budget allocation and prioritization strategies on station infrastructure quality is quantified by comparing different scenarios. Based on the results of the analysis, a quality assessment method can be evaluated, and disincentives can be identified. The analyses in this paper are carried out for quality measurement defined in Germany and the German railway station infrastructure

An English-language adaptation and validation of the Political Efficacy Short Scale (PESS)

The Political Efficacy Short Scale (PESS) is the English-language adaptation of the German-language Political Efficacy Kurzskala (PEKS); it measures perceived political efficacy with four items. PESS comprises two subscales - internal and external political efficacy - with two items each. Internal political efficacy refers to the belief in one’s own political effectiveness; external political efficacy refers to the belief in the responsiveness of the political system to citizens' concerns. Completion time for all four items is less than 30 s. The items of the German-language source version were translated into English using the TRAPD approach. The present study empirically validated the English-language adaptation (PESS) based on a heterogeneous quota sample in the UK. The results show that the reliability and validity coefficients of the English-language adaptation are sufficiently high and that they are comparable to those of the German-language source version. In addition, the scale showed strict measurement invariance (i.e., equal loadings, intercepts, and uniquenesses) when comparing the UK and Germany, which indicates the comparability of manifest scale scores (means and variances) and correlations across the two nations. As a short scale, PESS lends itself particularly to the measurement of political efficacy in survey contexts in which assessment time or questionnaire space is limited. It is applicable in a variety of research disciplines, including political science, sociology, psychology, and economics