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Level crossings represent high risk for both rail and road users due to the severe consequences of any possible accident. Between 2011-2020, a total of 1602 accidents occurred at level crossings in Germany and resulted in 344 fatalities. Therefore, elimination of accident risk through consolidation of level crossings becomes a priority. However, due to the scarcity of financial resources in comparison to the high costs that level crossings consolidation or safety upgrade projects require, there is a need for the creation of tools that prioritize the level crossings for consolidation projects based on several criteria that is not related to safety only but to social, economic and environmental aspects as well. Such tool would be particularly useful for authorities and decision-makers in Germany to improve the resource allocation process and increase overall safety at German level crossings. In this project, the level crossing prioritization and consolidation models that are applied all over the world are reviewed and analyzed to benefit from the international experiences in this field. Additionally, a literature review to determine the most influencing factors on level crossing safety was performed. After that, a points-based priority score for German level crossings was developed based on analytic hierarchy process (AHP) methodology after a pairwise comparison survey was conducted to a selected level crossing group of experts. The developed model assigns a priority score from 1000 points to each level crossing. Crossings could be ranked according to their priority for consolidation and safety upgrade based on the points received as crossings with the highest priority score have a higher priority for elimination.
Vehicular emission is often the main source of air pollution. The chief pollutants react with air and secondary pollutants resulting in adverse effects to the environment. European commission has legislated laws in order to reduce the air pollution from vehicular emissions.
Traffic modelling has been used for many decades and particularly in the last decade, flow of traffic based on vehicle type has been used to estimate emission of polluting gases and particles. Passenger car and Heavy duty Emission Model (PHEM) is used along with microscopic traffic flow simulation software VISSIM (In German: Verkehr In Städten – SIMulationsmodell meaning "Traffic in cities - simulation model") for estimation of major two major pollutants of greenhouse gases (carbon dioxide, nitrogen oxides) and particulate matter emitted from passenger cars and heavy-duty vehicles, based on their technical performance characteristics in a traffic flow at a typical German motorway segment. With a country’s fixed fleet composition for a particular year, PHEM gives fuel consumption and emission as outputs using fuel types used (diesel or petrol) and based on the trajectories of the vehicles.
This study is planned to exploit the developments and investigate the validation of this software with HBEFA. Different 25 scenarios are created for a German motorway segment with varying traffic behaviours; and the emission results between two emission modelling software tools are compared.
Railways is one of the most important ways of transporting people and goods from place to another in the whole world. In Germany, it comes as the second most used way of transport. The German railways network is so big and covers the whole maps of Germany. That is why it is so important to develop and improve the performance of it. At this thesis work, the performance of every route at the German railways is calculated using a digital model which is created in PTV Visum software using the programming language python. Furthermore, the workload of every node (junction) at the German Railways is calculated, and according to that, recommendations to build an overpass structure at the overloaded Junctions is suggested to improve the capacity of this Junctions.
The Faculty of Languages at the University of Applied Sciences Zwickau has a knowledge
base on critical incidents. Critical incidents capture and structure insights from critical situations in international mobility [Fet15]. With the rapid development of data and information, the
research platform CIs to Go has a clear need for a central search infrastructure that will allow
users to find and discover more relevant critical incidenst (or intercultural experinces as named
in the research platform CIs to Go). The data and information about critical incidents are stored
in open-source relational database management system PostgreSQL.
Nowadays it is inconceivable to use traditional RDBMS tools to analyze the data as they
grow very fast. The amount of information has steadily increased for years. Big Data provides
a solution for analyzing large amounts of data. Many search engine providers offer the solution
for analyzing large volumes of data, and companies are looking for open source solutions that
can quickly and reliably search, analyze, and evaluate large volumes of data. Elasticsearch
is a Lucene based search engine. Elasticsearch uses the concept of indexing to speed up the
search. This search engine provides a variety of options for free text queries, fuzzy matching
and indexing data. First, search engines and NLP toolkits are reviewed. This thesis also defines
the functional requirements of these tools. Then, an evaluation is given by indicating the positive
and negative aspects of the tools.
This thesis presents a complete search engine to be deployed on the research platform CIs
to Go as a new visual tool that helps in the process of searching for and finding intercultural
experiences.
The goal of this paper is to determine all relevant factors that influence the economic outcome and development of a country including the culture people practice. In the beginning of the paper it will be given a thorough explanation of culture and its components. There have been different theories on how culture influences the economic power of a country which until today are considered controversial. Therefore, it will be taken a closer look at for instance the theory of Max Weber, who explained in his book
Research and studies have indicated that rural highways globally exhibit a disproportionately high incidence of accidents and fatalities, which can be attributed to inadequate traffic safety measures. This paper primarily examines the causes of inadequate traffic safety, with a particular emphasis on factors associated with road conditions. These causes can be broadly categorized into human factors, road factors, and vehicle factors. Indeed, the movement of vehicles on these rural roads is characterized by unrestricted traffic flow, whereby the driving stability of a vehicle is primarily impacted by factors such as road alignments and surface conditions. Single-vehicle run-off-road crashes frequently exhibit a correlation with insufficient road conditions. Hence, enhancing the alignment design of roadways can prove to be efficacious in minimizing the occurrence of traffic accidents. However, constraints may arise in the context of rural roads, thereby imposing limitations on designers and engineers in their ability to modify road design. Therefore, it is imperative to explore alternative measures to enhance road safety as required. The objective of this study is to analyse driving behaviour on a two-lane rural road in Germany, taking into consideration the varying alignments of the road. The WHZ static simulator is an innovative technological tool utilized within the field of road design analysis, specifically for the purpose of evaluating driving behaviour. Speed, lateral positions, and are the primary parameters utilized in the evaluation of driving behaviours.
Keywords: Driving Simulators, Driving Behaviour, Traffic Safety, Trajectory Classification
China
(2015)
Within this Bachelor Thesis the Chinese economic development with begin of the economic boom until today are described. With focus on the Austrian Business Cycle Theory by Ludwig von Mises and Friedrich Hayek the questions why and how economic bubbles develop are investigated and similarities between countries who experienced economic bubbles in the past and China analysed. The conclusion of the research is that the Chinese real estate market has indeed been caught in a boom-and-bust cycle and is at the moment going through recession. A future reoccurence of an economic bubble in China is possible.
Electrical and thermal measurements were conducted during the plasma electrolytic polishing (PEP) of cemented tungsten carbide (WC-Co) materials to characterize energetic aspects of the process in relation to the temporal development of the gaseous layer near the workpiece. The power transferred to the workpiece is determined using a calorimetric probe and employing the time derivative of the temperature curve. It shows distinct heating phases due to the generation of the gaseous layer. At the beginning of the process, a typical power of 367 ± 17 W is transferred to the workpiece of a surface area of 14 cm2. At longer process times, a stabilized gaseous layer limits the power transferred to the workpiece to 183 ± 3 W. In an attempt to describe the heat transferred to the electrolyte, the electrolyte temperature was measured using a thermocouple situated 15 mm away from the workpiece. The local electrolyte temperature increases from 70 to 81 °C for an immersion depth of 20 mm. Moreover, the spatiotemporal development of the electrolyte temperature was obtained by 2D-hydrodynamic modeling using COMSOL Multiphysics®. The modeling results for the local temporal temperature development are in excellent agreement with the experimental values when the turbulent model is applied up to t = 65 s. Afterward, the laminar model leads to a better agreement. Furthermore, line scan x-ray photoelectron spectroscopy revealed that aliphatic carbon was preferentially removed. Only a slight compositional gradient in the vertical direction after the PEP process was observed.
The objective of this document is to design a connection between the devices of the two technologies SunSpec and Smart Energy 2.0 without the establishment of security backdoors. Smart Energy 2.0 devices should be able to gather data from SunSpec devices and modify writable registers for controlling purposes. Among other alternatives, the gateway proves itself as the most realistic and reasonable option and is chosen for further investigations. The connectivity requirements for such a device are analysed and mentioned. Interoperability between both networks is the core function of the gateway and established by the development of a Smart Energy 2.0 function set that implements the ability to represent SunSpec devices as resources in the Smart Energy 2.0 network. The gateway utilizes existing and introduces new mechanisms that maintain the high standard of security in Smart Energy 2.0 without any drawbacks. The document shows fundamental architectural approach and generally explains the functional and security mechanisms, but does not describe a complete gateway implementation.
Development and testing of a measuring system for recording mechanical loads on industrial batteries
(2019)
The electrical conduction mechanism of resistive switching Prussian white (PW) thin films obtained by the electrodeposition method was examined by AC impedance spectroscopy and DC current–voltage measurements. Using an electrode tip to contact PW grown over Au, robust unipolar resistive switching was observed with a current change of up to three orders of magnitude, high repeatability, and reproducibility. Moreover, electrical impedance spectroscopy showed that the resistive switching comes from small conductive filaments formed by potassium ions before the establishment of larger conductive channels. Both voltammetry and EIS measurements suggest that the electrical properties and conductive filament formation are influenced by defects and ions present in the grain boundaries. Thus, PW is a potential material for the next generation of ReRAM devices.
Prussian blue (PB) layers were electrodeposited for the fabrication of Au/PB/Ag stacks to study the resistive switching effect. The PB layers were characterized by different techniques to prove the homogeneity, composition, and structure. Electrical measurements confirmed the bipolar switching behavior with at least 3 orders of magnitude in current and the effect persisting for the 200 cycles tested. The low resistance state follows the ohmic conduction with an activation energy of 0.2 eV.
Multi-objective optimization of a model predictive vehicle dynamics control system using NSGA-II
(2022)
The development of the Automated Driving System (ADS) had a substantial significant impression on scientists. Throughout ADS, different units and controllers are installed, monitored, and analysed. The research is based on the theory of the Model Predictive Controller (MPC) system. which tackles the Multi-Objective Optimization (MOO) problem by calling out the cost function on the path-following problem using the MPC (i:e Model Predictive Path Following Control (MPFC)) with the defined constraints for the lateral control of the vehicle. The cost function helps to minimize the errors and compute the data. But the computation through the cost function is a bit complex. To overcome the complexity, an Non-Dominated Sorting Genetic Algorithm II (NSGA-II) algorithm is proposed, which helps to minimize the errors of set parameters and provides an optimal solution. The notion of NSGA-II is to find a wide variety of solutions and obtain better convergence in the form of the Pareto Optimal Front. Moreover, the detail of the Non-Dominated Genetic Algorithm II is theoretically enlightened to understand the Evolutionary Algorithm (EA) concept and the workability of the genetic algorithm. And the whole function is scripted in the MATLAB program.
Furthermore, we analyse the generated data in the Pareto Optimal Front and compare it with the Hyper-volume indicator, the most popular set-quality metric for rating stochastic multi-objective optimizer performance. Its theoretical characteristics, particularly the strict monotonicity concerning set dominance, which is still exclusive
to hyper-volume based indicators, justify its widespread acceptance. Hyper-volume indicator scrutinizes the optimal solution of multiple results. The analysis and
evaluation are completed between two other data sets generated and received through the RandomDATA and Multiple Objective Particle Swarm Optimization (MOPSO)
algorithm, which describe the quality of the best optimal solution between the results generated by the three algorithms.
Keywords: Non-Dominated Genetic Algorithm II, Model Predictive Path following Control, MATLAB, Algorithm, Pareto Optimal Front, Multi-Object optimization, Cost
Function