Dynamic Network Notation: A Graphical Modeling Language to Support the Visualization and Management of Network Effects in Service Platforms

Service platforms have moved into the center of interest in both academic research and the IT industry due to their economic and technical impact. These multitenant platforms provide own or third party software as metered, on-demand services. Corresponding service offers exhibit network effects. The present work introduces a graphical modeling language to support service platform design with focus on the exploitation of these network effects

Inciting Networks Effects Through Platform Authority: A Design Theory for Service Platforms

The provisioning of software has shifted towards a service model, where applications are hosted, metered, and billed through service platforms rather than being sold as on-premise software. These services can exhibit network effects, which are self-enforcing effects of value generation. They describe the interdependency of service or platform value, service consumption, and third party service provisioning. Service platforms need to be designed to incite these network effects. We propose a design theory which is based on the operator’s platform authority as the key factor for controlling and influencing stakeholders in and around the service platform in different control modes. As a design method, we propose a conceptual modeling language which supports service platform design with staged areas of authority, process flows as well as control methods. We present the rationale behind the language, discuss its application, and propose testable hypotheses for an empirical evaluation

An Information Systems Design Theory for Service Network Effects

Service platforms make software applications available as a service to end users. Platforms enable noticeable economic benefits for scaling and transforming a business. Their long-term competitiveness is ensured in controlled cooperation with channel intermediaries and network partners. Hence, service platforms must be designed to harness self-enforcing effects of value generation, so-called network effects. In an exaptation of existing knowledge, we present an information systems design theory to inform the design of methods that analyze, describe, and guide the design of service platforms through the means of causal loops and control methods. We describe the theory’s purpose and scope as well as the underlying justificatory knowledge behind the constructs and principles of form and function. The design theory covers the design of all service platform participants and activities as well as their transactions and influences in areas of staged platform authority, using enforcing and incentivizing control methods. We demonstrate the principles of implementation with an expository instantiation and apply it to the M-Engineering service platform, which offers surveillance, control, and data acquisition solutions. Furthermore, we present and discuss testable propositions and a study design to evaluate our design principles

Simulation of radio emission from cosmic ray air shower with SELFAS2

We present a microscopic computation of the radio emission from air showers initiated by ultra-high energy cosmic rays in the atmosphere. The strategy adopted is to compute each secondary particle contribution of the electromagnetic component and to construct the total signal at any location. SELFAS2 is a code which doesn't rely on air shower generators like AIRES or CORSIKA and it is based on the concept of air shower universality which makes it completely autonomous. Each positron and electron of the air shower is generated randomly following relevant distributions and tracking them along their travel in the atmosphere. We confirm in this paper earlier results that the radio emission is mainly due to the time derivative of the transverse current and the time derivative of the charge excess. The time derivative of the transverse current created by systematic deviations of charges in the geomagnetic field is usually dominant compared to the charge excess contribution except for the case of an air shower parallel to the geomagnetic field.Comment: 17 pages, 21 figure

Raumerleben junger Geflüchteter: Ergebnisse sozialräumlicher Forschung

Im Zuge der (Zwangs-)Migration kamen und kommen insbesondere junge Menschen nach Deutschland, um Schutz zu suchen. Entscheidende Weichen für die soziale, schulische und berufliche Integration können gerade in der Phase des Erwachsenwerdens gestellt werden. Zur Förderung und Unterstützung der Jugendlichen ist eine Orientierung an ihrer Lebenswelt geboten. Dazu zählen neben der Schule das Freizeitverhalten sowie die dabei genutzten Orte und Räume. Hieran knüpft die vorliegende Studie an und fragt nach relevanten (Freizeit-)Orten der Jugendlichen und den zugrundeliegenden Faktoren. Erkennbar ist, dass sich die geflüchteten nicht stark von den ‚einheimischen‘ Jugendlichen unterscheiden, beide Gruppen aber heterogen sind. Insgesamt zeigt sich für die geflüchteten Jugendlichen, dass sie räumlich mobil sind und die Orte ihrer (Freizeit-)Interessen sowohl im Nahraum als auch stadtweit und außerhalb der Stadtgrenzen liegen. Entscheidend für die Attraktivität der Orte sind u. a. Gleichaltrige, Bezugspersonen oder spezielle Bedürfnisse. Ausschlaggebend dafür, dass Orte gemieden werden, sind u.a. negative Erfahrungen, auch in Bezug auf Diskriminierung.In the course of (forced) migration, especially young people have come to Germany lately seeking protection. Decisions concerning social, educational and professional aspects of integration are pivotal during these stages of youth and young adulthood. In order to benefit and support young people, life-world orientation (Lebensweltorientierung) is required. In addition to school, this includes leisure time activities and the places and spaces used for this purpose. This is the starting point of the present study that asks for young people's relevant (leisure) places and the underlying reasons. One finding is that the refugees do not differ strongly from the 'natives', while both groups are heterogeneous. The young refugees appear to be spatially mobile, using places for (leisure) activities in the immediate vicinity as well as citywide and outside the city limits. Significant for the perceived attractiveness of places are i.a. peers, caregivers or special needs addressed. Negative experiences, e.g. of discrimination, are significant for the avoidance of places

Raumerleben junger Geflüchteter

RAUMERLEBEN JUNGER GEFLÜCHTETER Raumerleben junger Geflüchteter / Scholten, Lisa (Rights reserved) ( -

Serological and molecular survey of hepatitis E virus in cats and dogs in Spain

Hepatitis E virus (HEV) is an emerging zoonotic pathogen that is currently recognized as one of themajor causes of acute human hepatitis worldwide. In Europe, the increasing number of hepatitis E cases is mainly associated with the consumption of animal food products or contact with infected animals. Dogs and cats have been suggested as a zoonotic source of HEV infection. The aim of this study was to assess Orthohepevirus circulation, including HEV-A, HEV-B and HEV-C species, in sympatric urban cats and dogs in southern Spain. Between 2017 and 2020, blood samples were collected from 144 stray cats and 152 dogs, both strays and pets. The presence of antibodies againstHEV were tested using a double-antigen sandwich ELISA and seropositive simples were further analysed bywestern blot.ART-PCR was performed to detect RNAof Orthohepevirus species (HEV-A,HEV-B andHEV-C).Atotal of 19 (6.4%; 95%CI: 3.6-9.2) of the 296 animals tested showed anti-HEV antibodies by ELISA. Seropositivity was significantly higher in dogs (9.9%; 15/152; 95%CI: 5.1-14.6) than in cats (2.8%; 4/144; 95%CI: 0.1-5.5). Ten of the 18 ELISA-positive animals that could be further analysed by western blot, reacted against HEV-3 and/or HEV-C1 antigens, which suggest circulation of both genotypes in urban cats and dogs in the study area. However, HEV-A, HEV-B and HEV-C RNA were not detected in any of the tested sera. This is the first study to assess HEV circulation in both stray cats and dogs in Europe. Our results provide evidence of HEV exposure in sympatric urban cat and dog populations in southern Spain. Further studies are needed to determine the role of these species in the epidemiology of HEV

Universality of electron-positron distributions in extensive air showers

Using a large set of simulated extensive air showers, we investigate universality features of electron and positron distributions in very-high-energy cosmic-ray air showers. Most particle distributions depend only on the depth of the shower maximum and the number of particles in the cascade at this depth. We provide multi-dimensional parameterizations for the electron-positron distributions in terms of particle energy, vertical and horizontal momentum angle, lateral distance, and time distribution of the shower front. These parameterizations can be used to obtain realistic electron-positron distributions in extensive air showers for data analysis and simulations of Cherenkov radiation, fluorescence signal, and radio emission.Comment: 13 pages, 22 figures, 1 tabl