Selfish Mining and Dyck Words in Bitcoin and Ethereum Networks

The main goal of this article is to present a direct approach for the formula giving the long-term apparent hashrates of Selfish Mining strategies using only elementary probabilities and combinatorics, more precisely, Dyck words. We can avoid computing stationary probabilities on Markov chain, nor stopping times for Poisson processes as in previous analysis. We do apply these techniques to other bockwithholding strategies in Bitcoin, and then, we consider also selfish mining in Ethereum

Inland Waterways’ Importance for the European Economy. Case Study: Romanian Inland Waterways Transport

The paper deals to the need of a new approach for the inland water transport. There is a great contradiction between the European official documents related to the inland water transport and the practice. The analysis was focused on evaluating the present status of this type of transport and its future goals in the context of the new challenges to the EU28. The first intermediate conclusion of the analysis is that the great economic disparities between the Member States led to great disparities related to inland water fleet and infrastructure. As the result, the economic importance of this type of transport decreased in the EU28. A distinct part of the paper is dedicated to the inland water transport in Romania and focused especially on the Danube sector. This chapter points out the real economic, logistic and environmental challenges for Romania regarding the transport on Danube. A great challenge for the analysis in this paper was the difficulty to find official statistical data related to inland water transport across the EU28. The main conclusion of the paper is that the inland water transport will be not able to recover and develop on short and medium terms

A Case Study of the Use of Smart EV Charging for Peak Shaving in Local Area Grids

Electricity storage systems, whether electric vehicles or stationary battery storage systems, stabilize the electricity supply grid with their flexibility and thus drive the energy transition forward. Grid peak power demand has a high impact on the energy bill for commercial electricity consumers. Using battery storage capacities (EVs or stationary battery systems) can help to reduce these peaks, applying peak shaving. This study aims to address the potential of peak shaving using a PV plant and smart unidirectional and bidirectional charging technology for two fleets of electric vehicles and two comparable configurations of stationary battery storage systems on the university campus of Saarland University in Saarbrücken as a case study. Based on an annual measurement of the grid demand power of all consumers on the campus, a simulation study was carried out to compare the peak shaving potential of seven scenarios. For the sake of simplicity, it was assumed that the vehicles are connected to the charging station during working hours and can be charged and discharged within a user-defined range of state of charge. Furthermore, only the electricity costs were included in the profitability analysis; investment and operating costs were not taken into account. Compared to a reference system without battery storage capacities and a PV plant, the overall result is that the peak-shaving potential and the associated reduction in total electricity costs increases with the exclusive use of a PV system (3.2%) via the inclusion of the EV fleet (up to 3.0% for unidirectional smart charging and 8.1% for bidirectional charging) up to a stationary battery storage system (13.3%)

RESULTS OF A QUALITATIVE SURVEY ABOUT THE AP-PLICATION OF BUSINESS INFORMATION SYSTEMS IN GERMAN CRAFT ENTERPRISES - FIRST FINDINGS OF AN ONGOING RESEARCH PROJECT

The present study shows the current status of a preliminary study about the use of business infor-mation systems (BIS) based on five exemplarily selected case studies in German craft enterprises. The question of whether similarities and differences concerning the application of information and com-munication technologies (ICT) exist in practice. For this purpose, exemplary case demonstrating the scope and usage of organizational ICT in various crafts are presented. The case studies are based on a survey of CEOs and IT managers of selected craft enterprises. Based on the results of the survey, hypotheses about the use of information technologies were derived. Based on these hypotheses, inter-dependencies of craft enterprises are presented and justified regarding the use of BIS, the actuality of the hardware, the requirements to branch-specific IT solutions, the measures taken toward data pro-tection and data security and the visibility on the Internet. As a result of the preliminary study it can be stated that a widely heterogeneous IT landscape as well as good IT competence can be found in the enterprises involved

The EU´s political communication : communicating achievements to citizens in a changing environment : a cross-sectional-study involving Germany and Portugal

In view of the significant developments that the European Union’s (EU) political environment has undergone, this study aims at examining whether it’s institutions have adapted their political communication efforts credibly. The decade of 2008 to 2018 gave birth to fundamental environmental changes and major crisis confronting European liberal democracies and the whole Union. The digital transformation, the Eurozone and refugee crises and the rise of populist euroscepticism have changed the way citizens perceive the EU. The fact that most research in this field was conducted before this decade makes it urgent to examine the status-quo of the institutions communication and answer this study’s research question: Are the EU’s political communication actions up-to-date with the latest developments? To answer this, the study examines the developments in Germany and Portugal, that, being traditionally pro-European countries, were significantly affected by the different developments. Consisting of a two-step-analysis, the study includes a qualitative content analysis of the EU institutions’ awareness campaigns in 2018/2019 and a SWOT-analysis for the mid- to long term perspectives. The central finding of this study is that although the EU institutions are using the right tools to communicate to citizens they have missed out to confront the main drivers for euroscepticism and therefore reach citizens who are not yet convinced of the European project