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This paper presents an analytical method for determining the bending stresses and deformations in prismatic, noncircular profile shafts with trochoidal cross sections. The so-called higher trochoids can be used as form-fit shaft-hub connections. Hybrid (mixed) higher trochoids (M-profiles) were developed for the special application as a profile contour for the form-fit shaft and hub connections in an earlier work by the author. M-profiles combine the advantages of the two standardised polygonal and spline contours, which are used as shaft-hub connections for the transmission of high torques. In this study, the geometric and mechanical properties of the higher hybrid trochoids were investigated using complex functions to simplify the calculations. The pure bending stress and shaft deflection were determined for M-profiles using bending theory based on the theory of mathematical elasticity. The loading cases consisted of static and rotating bends. Analytical, numerical, and experimental results agreed well. The calculation formulas developed in this work enable reliable and low-cost dimensioning with regard to the stresses and elastic deformations of profile shafts subjected to bending loads.
Hypotrochoidal profile contours have been produced in industrial applications in recent years using two-spindle processes, and they are considered effective high-quality solutions for form-fit shaft and hub connections. This study mainly concerns analytical approaches to determine the stresses and deformations in hypotrochoidal profile shafts due to pure bending loads. The formulation was developed according to bending principles using the mathematical theory of elasticity and conformal mappings. The loading was further used to investigate the rotating bending behaviour. The stress factors for the classical calculation of maximum bending stresses were also determined for all those profiles presented and compiled in the German standard DIN3689-1 for practical applications. The results were also compared with the corresponding numerical and experimental results, and very good agreement was observed. Additionally, based on previous work, the stress factor was determined for the case of torsional loading to calculate the maximum torsional stresses in the standardised profiles, and the results are listed in a table. This study contributes to the further refinement of the current DIN3689 standard.
Boron-doped diamond (BDD) electrodes offer some excellent electrochemical properties, including the widest potential window in aqueous solutions, low background currents and good chemical and mechanical stability. They can also be produced transparent and could offer a great potential for spectroelectrochemical (SEC) experiments. However, to reach the mentioned electrical properties for such optically transparent electrodes (OTE), heavy doping is needed to increase conductivity. The introduction of boron in return reduces the transparency significantly. This work investigates the effect of introducing an alternative path for electrons in the form of an highly conductive get transparent interlayer which could increase the conductivity without increasing the BDD film or the doping level supporting high transparency in the visible (Vis) and ultraviolet (UV) regime. This work furthermore investigates possible interlayers for this application and implements four of them in two BDD OTE samples which are extensively studied by electrical, optical and electrochemical methods. An ultra-thin metal film (UTMF) of titanium (Ti) is shown to decrease the electrochemical resistance by 2.4kOhms while decreasing the transparency of a BDD OTE by only 11%.
China is planning to rebuild the ancient Silk Road into a modern infrastructre network, spanning Asia, Central Asia and Europe. The investements are high and are not paying off. This thesis is exploring the political reasons for China's plans and the impact the initiative has on the Chinese-Kazakh relationship.
Autonomous Vehicles (AVs) as a means of public transportation is set to revolutionize the mobility behavior of elderly people in the coming future. Though the vehicle manufacturers and corporates emphasize on potential benefits of AVs to elderly citizens, very little has been researched and studied about this large cohort (age 65+) in society. This study aims to measure the experience of the elderlies in this Highly Automat Shuttle (HAS) in Berlin and find out the potential pros and cons affecting the design, trust and security, and perception to adopt this technology in the future. Among the elderly respondents surveyed, 93% found the HAS convenient, with minor design issues addressed. Respondents (90%) were willing to use it for their first and last-mile journey and considered that the HAS would help improve the social participation of elderlies with mobility restrictions. However, elderlies still have trust issues integrating a fully driverless vehicle in the domain of public transportation. The significant findings on the difference in the experience of HAS between the elderlies, adults, and younger adults could be adopted to develop the design further, making it more comfortable and trustworthy towards the elderly population.
Die Diplomarbeit umfasst die Analyse der für den Prüfstand notwendigen Geräte, den Aufbau des Prüfstandes und die Programmierung von kundenspezifischen Applikationen mittels LabVIEW.
Stereo matching methods are usually relying on rectified images to calculate disparities. If the rectification is inaccurate or not present at all most stereo matching algorithms will produce distorted disparity maps. In this thesis an approach is described that overcomes this issue for the PatchMatch Stereo algorithm. As groundwork for stereo matching four rectification procedures namely Bouget
Duplex steels are used for applications that require high strength and ductility combined with good corrosion resistance. An economical welding technology to handle these steels is achieved by combining the MIG and TIG arc processes. The aim is to improve welding speed and quality by utilizing a TIG-MIG hybrid welding process to join 1.4462 duplex steel with a thickness of 2 mm. The interaction between the two arcs, caused by the blowing effect, is an enormous challenge that can be counteracted with a defined torch position and current modulation. For this purpose, a variation of the MIG (pulsed and AC pulsed arc) and TIG process (AC and pulsed DC) took place. The influence of electrical parameters on process stability and material transfer was investigated. For analysis, an evaluation of high-speed recordings (5000 frames per second) and synchronized measured current/voltage curves (200 kHz) is carried out. Based on a number of selected specimens, a welding procedure test according to ISO 15614-1 is performed to determine the welding seam quality. The test includes the characterization by tensile and hardness testing and macroscopic and microscopic examination. Additionally, the specimens are examined according to ISO 5817.
The atomizing gas dynamics and the applied process energy have a significant influence on the produced particles. The melting process of the two wires can be influenced by current modulation. As for arc welding processes, more and more electronic and software-controlled machines are being used for arc spraying and will have replaced conventional power sources in the future. Due to the highly dynamic, fast regulating computing technology in the latest energy source, technology arcs can be operated with different current forms and types. The modern machines allow process-stable, reproducible variation of the particles and heat input into the substrate. Constant and pulsed current can be used as current forms. Usable current types are direct current (DC) and alternating current (AC). The electrical parameters must be analyzed to evaluate the process behavior. The consumable used is a wire-shaped iron-based alloy with a diameter of 1.6 mm. Relevant process parameters such as basic current Iground, pulse current Ipulse, pulse duration tpulse, impulse frequency fpulse, and alternating current frequency, fAC, are varied and recorded using appropriate measurement technology. The aim is to change the process performance and thereby the particle formation in a broad band. High-speed images are used to observe the arc and the deposition process. In addition, particle sizes are determined.
This bachelor thesis is about the development and design of the suture-based HeartStitch MR device for functional restoration of the mitral valve when a mitral regurgitation is present. The mitral valve is one of the four existing heart valves and due to their load, the mitral valve is most commonly affected by valve defects. In case of a mitral regurgitation, the leaflets of the mitral valve are not closing tight enough, which causes a reflux of the oxygenated blood from the left ventricle into the left atrium. As consequence, the human body won't be sufficiently supplied with oxygen anymore, which results in a disproportionate cardiac output. Untreated, this can lead to respiratory dis-tress, cardiac arrhythmias and stroke or even to death. In this case, a heart surgery is essential to improve the patient
The removal of bacterial infections within the root canal system is still a challenge. Therefore, the cleansing effect of established and new irrigation-protocols (IP) containing silver diamine fluoride (SDF) 3.8% on the whole root canal system was analyzed using quantitative PCR (qPCR) and 4′,6-diamidino-phenylindole-(DAPI)-staining. Extracted human premolars were instrumented up to F2 (ProTaper Gold) under NaCl 0.9% irrigation and incubated with Enterococcus faecalis for 42 days. Subsequently, different ultrasonically agitated IP were applied to the roots: control (no irrigation), 1. NaOCl 3%, EDTA 20%, CHX 2%, 2. NaOCl 3%, EDTA 20%, 3. NaOCl 3%, EDTA 20%, SDF 3.8%, 4. SDF 3.8%, and 5. NaCl 0.9%. One half of the root was investigated fluorescent-microscopically with DAPI. The other half was grinded in a cryogenic mill and the bacterial DNA was quantified with qPCR. The qPCR results showed a statistically significant reduction of bacteria after the application of IP 1, 2, and 3 compared to the control group. While IP 4 lead to a bacterial reduction which was not significant, IP 5 showed no reduction. These data corresponded with DAPI staining. With qPCR a new molecular-biological method for the investigation of the complete root canal system was implemented. The novel IP 3 had an equally good cleansing effect as the already established IP.
This article presents a cost-effective ultraviolet-ozone cleaner (UV/O3 Cleaner) for surface pre-treatment of substrates in the field of semiconductor technology. The cleaner consists of two chambers, the upper one contains the electronics, including the time counter. The lower chamber contains the two UV sterilisation lamps and a UV reflector of anodized aluminium, which confines the area of high Ozone concentration in the area of interest. The device is successfully used for surface cleaning and modification of different materials. To this end, the two important wavelengths 253.7 nm (excitation of organic residues) and 184.9 nm (production of ozone from the atmospheric environment as a strong oxidant) were first detected. The effectiveness of UV/O3 cleaning is demonstrated by improving the properties of indium tin oxide (ITO) for OLED fabrication. The contact angle of water to ITO could be reduced from 90° to 3° and for diiodomethane, it was reduced from 55° to 31° within the 10 min of irradiation. This greatly improved wettability for polar and non-polar liquids can increase the flexibility in further process control. In addition, an improvement in wettability is characterized by measuring the contact angles for titanium dioxide (TiO2) and polydimethylsiloxane (PDMS). The contact angle of water to TiO2 decreased from 70° to 10°, and that of diiodomethane to TiO2 from 54° to 31°. The wettability of PDMS was also greatly increased. Here, the contact angle of water was reduced from 109° to 24° and the contact angle to diiodomethane from 89° to 49°.
Article Highlights
We report a cost-effective dry-cleaning device for surface cleaning and modification based on ultraviolet-ozone irradiation.
Contact angle measurements show an increase of wettability for different materials due to surface modification.
The UVO3 pre-treatment improves layer formation and optoelectrical properties of OLEDs.
Introduction: In the spring of 2020, coronavirus disease 2019 posed a substantial challenge for countries and their healthcare systems. In Germany, over 70% of all cancer patients are treated in an outpatient setting, so gynecologic oncology practices are the guarantors of optimal patient care. We developed a survey to evaluate the management of gynecologic oncology patients.
Methods: The survey consisted of 38 questions and was sent to the members of the Berufsverband Niedergelassener Gynäkologischer Onkologen in Deutschland e.V. (BNGO), a professional association of gynecologic oncologists in the outpatient sector in Germany.
Results: The survey was completed by 54 out of 133 (41%) gynecologic oncologists from 14 out of 15 (93%) federal states where the BNGO is represented. Facing the pandemic, popular measures were mask requirements (100%), restriction of access to practices (94%), increased number of disinfectant dispensers (85%), installment of panes of acrylic glass (76%), or spatial alterations (67%). For most patients the pandemic had no influence on prioritization of therapies (82%) or prescribed systemic treatments (87%). Despite an increase in perceived psychological burden among the staff (72%), 85% (45/54) of the practices were not offered any additional psychological support.
Discussion and Conclusion: As most cancer patients in Germany are treated in an outpatient setting, a suitable reaction of oncology centers to the new circumstances was crucial to secure optimal treatment and patient care. Nevertheless, the low prioritization of mental health or distress of healthcare workers poses a serious threat to the maintenance of optimal medical care in further waves of the pandemic.
This paper deals with systematic approaches for the analysis of stability properties and controller design for nonlinear dynamical systems. Numerical methods based on sum-of-squares decomposition or algebraic methods based on quantifier elimination are used. Starting from Lyapunov’s direct method, these methods can be used to derive conditions for the automatic verification of Lyapunov functions as well as for the structural determination of control laws. This contribution describes methods for the automatic verification of (control) Lyapunov functions as well as for the constructive determination of control laws.
Diese empirische Diplomarbeit in englischer Sprache wirft einen Blick auf den Status Quo des Estnischen HIV/AIDS Präventionssystems und entwirft Hypothesen und Vorschläge, dessen Wirkung zu verbessern. Die Grundlage bilden qualitative Interviews mit Schlüsselpersonen, welche die Phänomene Konsens, Kooperation und Kapazitätenschaffung sowie deren Bedeutung für die Estnische HIV/AIDS Prävention untersuchen. Bei diesen Phänomenen handelt es sich um wichtige und bisher unbestimmte Problemfelder, welche zum Teil den Widerspruch zwischen einer erfolgreichen politischen und ökonomischen Transition Estlands und der hohen HIV Prävalenzrate erklären. Die Ergebnisse dieser Arbeit beziehen sich auf das existierende Qualitätsmanagement von NGOs, die horizontale Kooperation von NGOs und die vertikale Kooperation von Staat und NGOs. Darüber hinaus wird der Aspekt der Führung sowie das Estnische Präventionsprogramm aus Mitteln des Globalen Found zur Bekämpfung von AIDS, Tuberkulose und Malaria betrachtet.
1 In an increasingly populated and technological world, manufacturing processes have become faster and data more voluminous. With this comes the need to store this massive production data and use real-time data monitoring tools to facilitate decision making in a plant. Concepts, derived from Pharma 4.0.
| 2 In the manufacturing environment there is, however, a big challenge in data collection and transmission, i.e. the communication between different equipments, sensors, and software. Since each manufacturer tends or has tended to use its own standards for programming and manufacturing the devices and tools.
| 3 Another major challenge is the secure transmission of data to avoid theft and cyber attacks, thus affecting the company's credibility and financial losses.
| 4 In this project the data transfer from Programmable Logic Controller (PLCs) was performed through the Matrikon Server and an interface belonging to the OPC Foundation, this technology allows the collection of data from different sources and delivers them safely to the process visualization software in a single language.
| 5 For software and hardware installation in a regulated environment, standards and validation methods need to be followed before, during and after installation of the required system.
| 6 This project aims to transfer data continuously and contemporaneously from a local source to the could environment and present the validation method used by pharmaceutical industries to validate this process in a GMP-regulated environment.
| 7 For the performance of the software installation, documents have been prepared and used to record and evidence the procedure. These documents were prepared and executed based on standards and methods relevant to the validation process.
| 8 The workers were also trained to know how to handle the data coming from production, and to be able to extract the value from it for different sectors, such as quality, raw material sector, energy sector, etc.
| 9 Finally, improvements were suggested for the documents and validation process used in this project. Since this installation will be used as a basis for future customer installations, not only for interfaces, but also for 1st and 2nd generation connectors.
This work aimed to apply the Floating Film Transfer Method (FTM), developed by Kaneto et.al., as a new way of coating planar and nonplanar substrates with photoresist. Focus laid on the creation of a workflow to coat the substrate and process it by UV-Lithography and Nanoimprint lithography. Conventional coating methods like spin-, spray- or dip coating are well established in today’s industry but are limited in their capabilities to coat curved and structured surfaces. FTM offers the possibility to overcome these limitations. Therefore, two negative resists AR N 4400 and AR N 4600 10 as well as two positive resists AR P 3110 and AZ MIR 701 were drop cast on deionized water. The resist spreads into a thin film that can be transferred to a planar or curved substrate. Profilometric and ellipsometric measurements were conducted to evaluate the topography of the resist. A non-uniform thickness distribution was found depending on the resist and parameters like solid content, water temperature, and the amount of surfactant. UV-Lithography and Nanoimprintl ithography were successfully performed with these films. Resolutions as low as 2,3±0,4 µm were achieved by UV-Lithography of AR P 3110. A periodic pattern with a pitch of 1,51 µm was transferred by thermal nanoimprint lithography to AR N 4400 10. As proof of concept Laser Direct Writing was performed to structure AZ MIR 701coated on a glass vial.
The thesis analysis the car parks’ elements and the factors that influence the drivers’ behaviour on them. Then makes an approach to the definition of the strategy of how the car drivers search for free parking spaces. The reason for it is that there is a need to assess car parks’ design parameters in the terms of their performance. One of the decisive factors is also the drivers’ behaviour. A car park simulation based on the environment of matrices is designed and implemented in MATLAB. The algorithm for searching for the parking spaces is designed and implemented within that as well. The results of the simulation are presented.
Morality confronts us in our daily life. Sometimes people do not act the way we would have expected it. One of the biggest culture differences can be found between China and Germany. A lot of foreigners try to make business in the more and more economic important becoming country. A lot of them fail, because of not knowing how to act in certain circumstances. Furthermore, some situations are happening which one would not expected. Everyone got influenced by media about China. But is everything true about it? Most of the journalists are from western countries and they decide what is right and what wrong dependent from their origin. We call such a situation ethnocentrism. It means, that one judges dependent on ones ethnical norms one raised up with and that these norms are basis of valuation on other cultures (Schubert, 2011). While I was in China, I experienced a lot moral misunderstandings. I found out that especially foreign companies do have huge problems in that term because they use their - grown up morality- in China which is not working. This paper explains moral inequalities and helps companies to act differently in consideration of a very important topic such as payment morality.
In this paper, we propose cache replacement strategies based on the machine learning methods. As part of this work, we analyse the data provided for caching, design, and train Random Forest Regression and Gradient Boosting Decision Trees to predict the popularity of web objects. Finally we compare the proposed strategies with policies traditionally used for cache replacement to evaluate their applicability.
Sustainable Integration of Digitalisation in Nursing Education - An International Scoping Review
(2024)
This thesis aims to explain the German and Indian Road & Traffic designing, Green & Smart roads. This topic mainly involves around how both the countries are maintaining a different set of standards in designing roads and analysing them. India is the 2nd largest road network in the world and Germany having a greater number of highway connectivity throughout the country if the area isn’t considered both the countries have an equal amount of road connectivity. When we mainly consider Road, traffic designing, Green & Smart Road concepts practiced in both the countries the methods, procedures and standards used are different. Here we will analyse key factors that play a major role in differentiating Road and traffic designs and by considering some conditions and situations from both the countries we will analyse them. we will also analyse how much efforts are put in to implementing the Green, smart roads and we will further analyse how far did both the nations implemented their ideas and how much effect did it show and we will go through the Solar power produced, support for electrical vehicles, Automation improved and Iot (Internet of things) implemented for less human interactions and more advancement in transportation.
This research investigates the Leipzigerstraße and Gießereistraße intersection in Rackwitz to enhance safety and sustainable transportation. The study analyzes existing designs that experience accidents and proposes a design plan of mini roundabout to improve safety while using the guideline Anlage von Kreisverkehren. In this project, the roundabout is planned according to the currently valid guidelines from phase 2 of the HOAI (Fee Structure for Architects and Engineers). Rainwater management strategies and traffic quality of the roundabout are considered. Additionally, cyclist-friendly paths connecting Rackwitz and Zschölkau are developed in line by using guideline ERA. The proposed roundabout design and elevated cycle paths are identified as effective solutions to enhance safety and support eco-friendly transportation. By adhering to established guidelines and prioritizing safety, this research contributes to creating a secure and sustainable urban transportation network.
Development and Characterization of a Dispersion-Encoded Method for Low-Coherence Interferometry
(2022)
This Open Access book discusses an extension to low-coherence interferometry by dispersion-encoding. The approach is theoretically designed and implemented for applications such as surface profilometry, polymeric cross-linking estimation and the determination of thin-film layer thicknesses. During a characterization, it was shown that an axial measurement range of 79.91 µm with an axial resolution of 0.1 nm is achievable. Simultaneously, profiles of up to 1.5 mm in length were obtained in a scan-free manner. This marked a significant improvement in relation to the state-of-the-art in terms of dynamic range. Also, the axial and lateral measurement range were decoupled partially while functional parameters such as surface roughness were estimated. The characterization of the degree of polymeric cross-linking was performed as a function of the refractive index. It was acquired in a spatially-resolved manner with a resolution of 3.36 x 10-5. This was achieved by the development of a novel mathematical analysis approach.
ABSTRACT:
Multimodal transportation system which is also called as Combined transportation system. This type of transportation is seen in two methods i.e., movement of passengers from one place to another and movement of cargo using different types of transportation vehicles (Trains, trams, metro, bus, ship, truck, bicycle, airplane and air cargos). This type of system can also be derived
as single ticket (passengers) and single contract (freight) transportation. This will help in reducing the travel time, air pollution, economy, environmental changes, and unorganized journey. The main goal of the thesis is to bring ease in the multi-modal transportation system in India and to make people choose public transport over private and to provide end to end transportation facilities for people, so that people opt for public transportation as it is budget friendly as well. For instance, prevailing the single ticket (passengers) and single contract (freight) transportation system in Germany could be implemented in India. A single transport operator system is needed to meet the desired target in implementing multi-modal transportation
system feasibly. The main issue lies in the implementation of this system in Indian conditions which can be fulfilled by integration of various institutions involved in it for instance linking up the network channels of various modes of transport (end to end transportation). The rising concerns of funding by Indian government can be resolved by the implementation of this system
in the form of subsidies.
My research paper also includes the phases of MMTS, how it was earlier and how it has been in contemporary times. Major Factors like total cost, reliability, transportation capability, total time and security drive forward to developing multi-modal transportation system. This system is helpful in the growth of a nation's economy and is energy-efficient. Reliability of this system shall be based on the funding from the government because the absence of multi-modal transportation system leads to pollution, and ill health. The amount of funding plays a vital role in determining country to country (MMTS) development. Having been considering the advantages and uses of this system it is important to look into the disadvantages of the system.
For instance, How can implementing multi-modal transportation system in India be feasible?
This master's thesis focuses on developing a robust framework for co-simulating microscopic traffic scenarios and vehicle dynamics, leveraging the capabilities of SUMO and CARLA. The essence of this research lies in its meticulous analysis of existing simulation tools, leading to identifying the most effective co-simulation strategies and intercommunication methods. A comparative study elucidates the strengths and limitations of these methodologies, guiding the selection of an optimal approach.
Central to the methodology is a thorough understanding and application of SUMO and CARLA, enhanced by the strategic implementation of intercommunication methods. The detailed integration of these tools and the introduction of test automation significantly boost simulation efficacy. The framework's reliability and accuracy are rigorously validated through well-defined procedures and metrics, ensuring fidelity in simulation results.
Key to this research is the design of experimental scenarios that reflect real-world traffic conditions underpinned by carefully chosen simulation parameters. These scenarios are pivotal in validating the co-simulation framework's performance, supplemented by a performance cost analysis focusing on processing efficiency. The thesis culminates with a critical discussion of the findings, addressing the research objectives and posing solutions to identified challenges. Potential areas for future enhancements are explored, highlighting the framework's limitations.
In conclusion, this thesis contributes significantly to the field of traffic simulation for autonomous driving technologies. It presents a comprehensive co-simulation framework, offering researchers and engineers a sophisticated tool for advanced testing and validation. The insights and recommendations provided are instrumental for ongoing research and development in this rapidly evolving domain.
In this study more than 150 kg real waste from electrical and electronic equipment (WEEE) shredder residues from different European dismantling plant were treated by laserspectroscopic flouroescence and solvent-based recycling process. Currently, the samples used are excluded from material recycling and remain as side streams in state-of-the-art plastic recycling plants. The main reason why the waste streams are not currently recycled is due to the fact that they contain flame retardants that are already banned by different EU regulations (e.g. REACH, POP) and must be removed before the recyclates produced can be used again in products on the market. Conventional recycling technologies cannot separate these hazardous flame retardants from the polymers, therefore the solvent-based recycling process was used for this study. The focus within this work was the upscaling of the CreaSolv® Process from the laboratory scale to the small technical scale to provide larger quantities of recyclates. Sensor-based sorting process and CreaSolv® Process were combined to achieve easier handling and better yields of recyclates. By means of safe solvents a significant decrease of halogen content of (up to 98%) was achieved within the applied methods. Mass balances were determined, and gas chromatography-electron capture detector (GC-ECD) as well as energy dispersive X-ray fluorescence (EDXRF) measurements provided data on the different flame retardants and halogen content of each recyclate. As a result, the recyclates produced comply with the limit values of the EU directives (e.g. POPs, REACH). Melt flow analysis and differential scanning calorimetry (DSC) were carried out on the recyclates for a quality evaluation and revealed that the recyclates have similar properties to virgin materials. Based on this work, the upscaling of the CreaSolv® Process is able to recycle WEEE containing pollutants and at the same time produce recyclates with good mechanical properties.
Developing of a marketing-mix for Duerr Ecoclean for the modified Spray Cleaning Machine "Jeto 84W". Duerr Ecoclean already established its business within the Chinese Automotive Industry and is now trying to touch the Chinese Component Industry. Therefore, they are looking for a suitable strategy to enter this market. The thesis included an analysis of the market environment, customer base, and competitor structure to develop a fitting marketing-mix to implement the Spray Cleaning Machine "Jeto 84W".
Model predictive control (MPC) is a promising approach to the lateral and longitudinal control of autonomous vehicles. However, the parameterization of the MPC with respect to high-level requirements such as passenger comfort, as well as lateral and longitudinal tracking, is challenging. Numerous tuning parameters and conflicting requirements need to be considered. In this paper, we formulate the MPC tuning task as a multi-objective optimization problem. Its solution is demanding for two reasons: First, MPC-parameterizations are evaluated in a computationally expensive simulation environment. As a result, the optimization algorithm needs to be as sample-efficient as possible. Second, for some poor parameterizations, the simulation cannot be completed; therefore, useful objective function values are not available (for instance, learning with crash constraints). In this work, we compare the sample efficiency of multi-objective particle swarm optimization (MOPSO), a genetic algorithm (NSGA-II), and multiple versions of Bayesian optimization (BO). We extend BO by introducing an adaptive batch size to limit the computational overhead. In addition, we devise a method to deal with crash constraints. The results show that BO works best for a small budget, NSGA-II is best for medium budgets, and none of the evaluated optimizers are superior to random search for large budgets. Both proposed BO extensions are, therefore, shown to be beneficial.
Methods of analyzing the structural integrity of compound materials under stressed conditions becoming more importantly. Not merely safety and economic reasons demanding a good monitoring of e.g. wind turbine blades or aircraft wings but also ecological ones. The existing strategy for the blades is to replace them at a certain schedule, resulting in unnecessary downtimes and high cost. Several possibilities of an optical structural health monitoring system been examined in this thesis. Both free-space and fiber-based setups are tested and evaluated in their usability. The methods were tested with the objective of embedding them into large-scale polymer structures such as the mentioned fields of application.
Experimental tests on the type-approval of motor vehicles with regard to safety belt anchorages, ISOFIX anchorages and ISOFIX top anchorages have been carried out in accordance with Regulation No. 14 UNECE. From the design stage, the safety belt anchorages must comply with the requirements for the installation of a safety belt and reduce slipping and damage to the belt while wearing it. These can be components of the seat structure or of the body's resistance structure, which have the role of fastening the seat belts. The position of the anchor points is determined by the R point. The R point is defined as the seat reference point on the seat. This point is set by the vehicle manufacturer for each seat in the vehicle. In this paper, two models of chairs were tested. Both seat models are equipped with seat belts anchored at three anchor points. Seat belt anchorages were tested simultaneously using parallel force devices. These traction devices are placed on the seat cushion and are pressed into the seat back. The pulling device has a vertical pulling arm, which has the role of anchoring the steel wire cables. Two test forces are applied simultaneously to the anchor points during the test.
This study aimed to investigate the component structural behaviour and response under overturned truck crash that subsequently collides with road-side pole or tree. The safety of the truck occupants in an accident is very important and should be considered in the process of cabin design. Specific focus will be on the structural integrity of the truck cabin in response to a collision with a cylindrical pendulum. In the past, dynamic analysis was done by real world testing. Nowadays crash simulation is proven to be much more efficient by being a virtual representation of destructive crash impact and providing opportunities to reduce the number of physical prototypes consumed for design verification, thus reducing development time. According to cab strength tests (ECE R29), the cabin body of the truck shall be attached to the chassis in such a way that in the event of impact it ensures a sufficient survival space and eliminates the risk of injury. This paper investigates the FE (finite element) simulation of a frontal impact on the cabin structure to validate the cabin according to the ECE regulation 29 tests. The study also includes the assessment of the energy absorption capabilities of the cabin during the pendulum impact. The pendulum impact was carried out using Ansys LS-Dyna explicit solver to evaluate the cabin strength under the loads.
The impact of work environment factors has to be considered in an integrated ergonomic analyzing and designing process. To capture relevant environmental exposures, measurements must be carried out. In companies, an increasing use of smartphones for initial measurements of work environment factors can be noticed. Here, the question arises whether it is possible to determine adequate data for scientific work analyses by using built-in sensors in smartphones. For that purpose, the operational readiness of smartphone applications to measure the work environment factors noise, climate and lighting is investigated. Here, the assessing of measuring accuracy and the recordable measurement quantities for different combinations of applications and smartphones is analyzed. In result, a wide variety of the measurement accuracy for the analyzed environmental factors can be observed.
The birefringence of single crystal diamonds is quantified using a birefringence measurement setup and a Matlab program for the calculation. The theoretical backgrounds of the polarization of light and polarization changing equipment is used for selecting a plane polariscope measurement method. Here, a birefringent sample is placed between two optical polarizers. The equipment, as well as its theoretical and practical behavior in the measurement setup is discussed. The equations for birefringence measurements are given and a practical Matlab program is introduced to simplify the birefringence calculation for the user. Possible influences on the birefringence value due to inaccuracies of the laser, the polarizers, the diamond sample, the magnification lenses and the camera are discussed and taken into account. Intensity fluctuations and polarization changes of the laser beam are studied. The direction of the transmission axis of the polarizer and the analyzer is examined. A retarder is inserted into the measurement setup to check the accuracy of the birefringence measurement since a retarder has a known phase retardation. This retarder measurement should qualify the measurement setup to quantify birefringence of the diamond sample. The measurement results show that intensity fluctuations of the laser and the handling inaccurracies of the polarizers have a major influence on the accurracy of the birefringence measurement. This measurement setup is not qualitfied to measure birefringence accurate yet. Steps to improve the measurement setup and the birefringence calculation are discussed.
To improve the quality of education in applied laser physics, a new and innovative educational platform was designed, realized and tested. The system focusses on the improvement of the theoretical, experimental and numerical skills in the topics of ultra-short pulsed fiber based laser systems and related measurement techniques. The main content of the platform is the fundamental understanding of the technologies of an ytterbium-doped fiber based Master-Oscillator Power-Amplifier and a 2nd order intensity autocorrelator. A wide range of system parameters are variable and metrologically accessible. Thus the underlying physical mechanisms are illustrated and, by this the fundamental understanding of the system, improved. To transfer actual industrial and scientific topics into the experimental education of students, the complex lab course aims for a full characterization of the system by experimental work and a numerical analysis by simulating the system dynamics. A state-of-the-art educational tool was created to demonstrate current industrial sys-tems. An amplification of 37.2 dB was achieved. The pulses with a temporal width of 30.6 picoseconds possessed a pulse peak power of 14.2 kW. By the analysis of the material specific spectral properties, the rate equation model can be applied and im-portant system parameters determined.
This thesis will examine the process of internationalization which generates international changes and growth, entry into new markets and the creation of new businesses. Projecting this on the sports industry, businessmen tend to take more risks than a few decades ago in the interest of becoming more competitive. The sports industry is used to transmit multiple messages as it reaches global audiences. The term sports covers much more than the physical activity. The term also comprises possibilities for lucrative business actions, sponsoring and image creation. Furthermore, it induces a pooling of diverse cultures. Thanks to this boundary-spanning connection of sportsmen and arising opportunities to increase sales, managers have decided to go international and to expand their company
Natural varnishes have been used for centuries by musical instrument makers to protect the instruments for climatic, aesthetic and acoustic reasons. The effects of varnishes on the protection of the wood surface, as well as their aesthetic parameters, are easier to verify and compare visually, but the comparison of their acoustic effects has always been challenging and debated.
In fact, varnish layers have a small effect on the vibration properties of wood. For example, the effect of a decrease or increase in humidity on the vibration properties of wood is sometimes equal to the effect of several layers of varnish. Because of this small amount of effect, measuring this effect is also difficult and challenging.
Our strategy in this study is to obtain the clearest possible results by comparing the effect of only two types of oil varnishes with completely opposite elastomechanical properties and increasing the number of samples varnished.
The samples were measured before and after each varnish layer using conventional methods for measuring vibration properties, and the average results of the same samples were discussed and analyzed.
Overall, the amber varnish obviously has a more negative effect on the vibration properties of the violin plates compared to the colophony varnish.
This work is aimed to study the effect of two types of stresses/corrosion on different materials used in making of disc brake rotors, atmospheric corrosion and thermal fatigue. The materials chosen were steel (100Cr6), nodular cast iron (GJS-400-15) and Aluminium reinforced silicon carbide (F3S-20S). Specimens of the each material will be subjected to an induced atmospheric corrosion using the salt spray (fog) chamber for two different test durations to simulate atmospheric corrosion. Other specimens of the chosen materials will be subjected to a thermal fatigue test through a repeated heating-cooling cycle. The effects on the materials will be measured by the difference in the values of coefficient of friction and the wear rate before and after the tests are carried out. Analysis of the induced corrosion and thermal fatigue products will be carried out by XRD analysis and microscopic photos of the surfaces. A comparison between the different tested materials will also be performed.
With the launch of a new vehicle model Rolls-Royce Motorcars had to face a dramatic volume increase from 300% more cars being build in existing structure and facilities in the Test and Finish Area. This massive volume increase required a revisiting of the process flow of cars through this Test and Finish Area to show optimisation potential and possible improvements to work packages and sequence of operation. Furthermore it will be necessary to implement those improvements to cope increased future throughput targets. To find optimisation and improvement potentials it was essential to analyse the entire area. In doing so every single station and work package was analysed. In addition to this a simulation model was used to confirm the highlighted problems and bottlenecks. Furthermore it was possible to investigate the influence of certain measures. In a following step it was the aim to show a way how a permanent and stable vehicle flow is achievable. According to that an action plan was developed, which shows clear measures to cope not only future but also the current production volume. In doing so it was possible to gain a transparency into the processes. Furthermore the process flow was optimised into a pull strategy to improve respectively implement a takt adherence.
was ist HIV/AIDS? Wie ist HIV/AIDS verbreitet in der Welt? HIV/AIDS in Tanzania: heute und in Zukunft Auswirkungen von AIDS auf Struktur und Zusammensetzung der Arbeitskräfte in Tanzania -> ableitend davon Auswirkungen auf betriebe, auf die Wirtschaftallgemein, auf verschiedene Wirtschaftszweige -> außerdem inwieweit AIDS den einzelnen Haushalt betrifft, insbesondere Frauen Zusammenspiel von Armut und AIDS
Active Traffic Management Systems – Developing a Package of Measurements for the City of Füssen
(2021)
Intelligent Transportation Systems (ITS) and Active Transportation and Demand Management (ATDM) are new commanders in the world of transportation engineering. The combination of ATDM and ITS has created a concept called “Active Traffic Management (ATM)”. The world’s ATM is getting a higher point for major technological changes that have been bringing new ways in public and private transport managing, decision making, smart cities, traffic control, safety and environment.
The management, control, influence of travel demand and traffic flow in transportation facilities is referred to as ATM. Actions are taken in real time to improve system performance, such as preventing or delaying breakdown conditions, enhancing safety, encouraging sustainable travel modes or cutting emissions, using archived data and or/predictive methods.
In this Master's thesis, it has been exanimated the prominent different areas of Active Traffic Management in traffic engineering with a special focus on the sections of traffic management, signal control, and simulations with the program VISSIM. To discuss this issue, this paper begins with a brief introduction of the names and concepts of the current technologies in ATM, followed by an example. Important data and challenges for the study case of the city of Füssen in Germany will be presented in the text, subsequent to some results, conclusions and recommendations. In addition, the current and alternative scenarios with their respective level of service are researched according to German regulations. A simulation of different nodes has been modeled to observe the respective delays, level of services and emissions of the intersections selected in the city.
Keywords
Traffic Engineering, Intelligent Transportation Systems (ITS), Active Traffic Management (ATM), Level of Service (LOS) and Traffic Simulation.
The labor market is confronted with social, environmental, and economic developments that affect working conditions and individual labor relations. Lately, the Covid-19 pandemic has demonstrated and reinforced the importance of inclusive growth and sustainable work relationships. In this chapter, the smart job factory, a metamodel that supports the creation of new forms of work by redefining roles in labor, is introduced. The smart job factory is based on social entrepreneurship principles to drive innovative, sustainable, and long-term solutions to social challenges. For practical application, the model can be translated into a software solution that supports employers in the assessment of current working conditions and job roles within their companies and helps to redefine work relationships and to create new jobs. Thus, the smart job factory supports the labor market transition by systematically and proactively shaping new forms of work based on the triple bottom line of sustainable development.