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In diesem Beitrag wird zunächst ein einführender Überblick über die Thematik eines Marketing-Controlling spezifischen Rechtsrahmens gegeben. Da die Datenerhebung, -verarbeitung und -analyse stets die Hauptfunktionsmerkmale eines Marketing-Controllings sind, stehen nach diesem Überblick die Rechtsgrundlagen eines Datenschutzes im Mittelpunkt der folgenden Ausführungen.
Many countries offer state credit guarantees to support credit-constrained exporters. The policy instrument is commonly justified by governments as a means to mitigating adverse outcomes of financial market frictions for exporting firms. Accumulated returns to the German state credit guarantee scheme deriving from risk-compensating premia have outweighed accumulated losses over the past 60 years. Why do private financial agents not step in and provide insurance given that the state-run program yields positive returns? We argue that costs of risk diversification, liquidity management, and coordination among creditors limit the ability of private financial agents to offer comparable insurance products. Moreover, we suggest that the government’s greater effectiveness in recovering claims in foreign countries endows the state with a cost advantage in dealing with the risks involved in large export projects. We test these hypotheses using monthly firm-level data combined with official transaction-level data on covered exports of German firms and find suggestive evidence that positive effects on trade are due to mitigated financial constraints: State credit guarantees benefit firms that are dependent on external finance, if the value at risk which they seek to cover is large, and at times when refinancing conditions on the private financial market are tight.
In this paper, a systematic comparison of three different advanced control strategies for automated docking of a vessel is presented. The controllers are automatically tuned offline by applying an optimization process using simulations of the whole system including trajectory planner and state and disturbance observer. Then investigations are conducted subject to performance and robustness using Monte Carlos simulation with varying model parameters and disturbances. The control strategies have also been tested in full scale experiments using the solar research vessel Solgenia. The investigated control strategies all have demonstrated very good performance in both, simulation and real world experiments. Videos are available under https://www.htwg-konstanz.de/forschung-und-transfer/institute-und-labore/isd/regelungstechnik/videos/
This paper describes the development of a control system for an industrial heating application. In this process a moving substrate is passing through a heating zone with variable speed. Heat is applied by hot air to the substrate with the air flow rate being the manipulated variable. The aim is to control the substrate’s temperature at a specific location after passing the heating zone. First, a model is derived for a point attached to the moving substrate. This is modified to reflect the temperature of the moving substrate at the specified location. In order to regulate the temperature a nonlinear model predictive control approach is applied using an implicit Euler scheme to integrate the model and an augmented gradient based optimization approach. The performance of the controller has been validated both by simulations and experiments on the physical plant. The respective results are presented in this paper.
inno4regio
(2021)
Unternehmen stehen häufig unter einem Innovationsdruck, um ihre langfristige Wettbewerbsfähigkeit zu sichern. Vor allem kleine und mittelständische Unternehmen sind hier besonders gefordert, da ihnen vielfach die erforderlichen Ressourcen oder Kompetenzträger fehlen und das tägliche operative Geschäft häufig eine intensive Auseinandersetzung mit dem Thema nicht zulässt.
Diese Unternehmen sind auf externe Ressourcen angewiesen. Hinzu kommt die Unsicherheit vieler Unternehmer hinsichtlich Kooperationsmöglichkeiten mit öffentlichen Forschungseinrichtungen sowie organisatorische Bedenken mit dem damit verbundenen Koordinationsaufwand.
Das Innovationsportal inno4regio kann genau hier Abhilfe schaffen. Mittels standardisierter Prozesse soll den Unternehmern eine Möglichkeit geboten werden, externe Innovationsvorhaben durch eine Problemanalyse anzustoßen und die notwendigen Partner aus der Hochschulwelt einzubinden. Der Zugriff über einen Knotenpunkt auf das fachliche sowie kreative Personal von rund dreißig Hochschulen im Verbund der Internationalen Bodensee-Hochschule ist dabei ein Alleinstellungsmerkmal, welches in dieser Form bisher noch nicht am Markt existiert.
This paper presents a generic method to enhance performance and incorporate temporal information for cardiorespiratory-based sleep stage classification with a limited feature set and limited data. The classification algorithm relies on random forests and a feature set extracted from long-time home monitoring for sleep analysis. Employing temporal feature stacking, the system could be significantly improved in terms of Cohen’s κ and accuracy. The detection performance could be improved for three classes of sleep stages (Wake, REM, Non-REM sleep), four classes (Wake, Non-REM-Light sleep, Non-REM Deep sleep, REM sleep), and five classes (Wake, N1, N2, N3/4, REM sleep) from a κ of 0.44 to 0.58, 0.33 to 0.51, and 0.28 to 0.44 respectively by stacking features before and after the epoch to be classified. Further analysis was done for the optimal length and combination method for this stacking approach. Overall, three methods and a variable duration between 30 s and 30 min have been analyzed. Overnight recordings of 36 healthy subjects from the Interdisciplinary Center for Sleep Medicine at Charité-Universitätsmedizin Berlin and Leave-One-Out-Cross-Validation on a patient-level have been used to validate the method.
Das produzierende Gewerbe in Deutschland erlebt aufgrund von Technologiewandel im Automobilbau, der Anpassung von Lieferketten und der digitalen Transformation grundlegende Veränderungen. Diese als Chance für künftiges Wachstum zu begreifen ist essenziell und eine zwingende Voraussetzung für den Wirtschaftsstandort Deutschland. Anhand eines konkreten Unternehmensbeispiels werden hierfür zentrale Aspekte für Transformation eines mittelständischen produzierenden Blechbearbeitungsunternehmens hin zu einem netzwerkbasierten Geschäftsmodell betrachtet. Auf Basis der Analyse von Referenzbeispielen webbasierter Vertriebsplattformen in der Blechbearbeitung werden erfolgsrelevante Aspekte für die Ausgestaltung und die Umsetzung für ein Onlineplattformmodell beschrieben. Hierbei wird exemplarisch dargelegt, wie mittels digitaler Vertriebsplattformen in Verbindung mit digitalen Auftragsmanagementprozessen neue Wege für Wachstum ermöglicht werden können.
Im Zuge zunehmender Effizienzbestrebungen in produzierenden Unternehmen spielt auch die Optimierung von indirekten Wertschöpfungsprozessen eine immer größere Rolle. Neben einer ansteigenden Aufgabenvielfalt stellt ein parallel wachsender Kostendruck eine doppelte Herausforderung dar. Dies gilt insbesondere für Einkaufsbereiche entsprechender Organisationen, welche an der Schnittstelle zwischen der unternehmensinternen und -externen Wertschöpfungskette operieren und an dieser einen essenziellen Beitrag auch im Sinne des Informationsflusses zur Unterstützung eines integrierten Supply Chain Managements darstellen. Um diesen zu begegnen, ist es notwendig, die relevanten Kernprozesse der Einkaufsbereiche stetig im Blick zu halten und Verbesserungsmöglichkeiten zu identifizieren und umzusetzen. Dieser Beitrag will zu einem Überblick für die Prozessoptimierung mithilfe des Einsatzes digitaler Technologien speziell in Einkaufsbereichen beitragen. Es werden die Spezifika des Einkaufs vorgestellt, relevante Kernaufgaben beschrieben und exemplarisch technologische Ansätze zur Prozessoptimierung anhand von Process Mining, Robotic Process Automation und künstlicher Intelligenz aufgezeigt.
A nonlinear mathematical model for the dynamics of permanent magnet synchronous machines with interior magnets is discussed. The model of the current dynamics captures saturation and dependency on the rotor angle. Based on the model, a flatness-based field-oriented closed-loop controller and a feed-forward compensation of torque ripples are derived. Effectiveness and robustness of the proposed algorithms are demonstrated by simulation results.
Innovation Labs
(2021)
Today's increasing pace of change and intense competition places demands on organizations to use a different approach to innovation, going beyond the incremental innovation that is typically developed within the core of the organization. As an option to escape the existing beliefs of the core organization, innovation labs are used to develop more discontinuous innovation. Despite the abundance of these so-called innovation labs in practice, researchers have devoted little effort to scrutinizing the concept and to provide managers with a framework for exploiting this form of innovation. In this paper, we aim to perform an empirical investigation and to create a consensus around the concept of innovation labs. To do so, we conducted a multiple case study in large international organizations with a total of 31 interviews of an average length of 70 minutes. We offer a framework by identifying four innovation lab types and consider when each is most appropriate. Furthermore, we highlight the importance for managers and their organizations to align the strategic intent with the innovation lab type as well as the interface between the innovation lab and the core business.
The main objective of this paper is to revisit the Euro method in a critical and constructive way.Wehave analysed some arguments against the Euro method published recently in the literature as well as some other relevant aspects of the SUT-Euro and SUT-RAS methods not covered before. Although not being the Euro method perfect, we believe that there is still space for the use of the Euro method in updating/regionalizing Supply and Use tables.
Diese Bachelorarbeit befasst sich mit einem Kooperationsprojekt in Botswana, welches durch Lehrende und Studierende der Hochschule für Technik Wirtschaft und Gestaltung in Konstanz und einigen Experten aus aller Welt umgesetzt werden soll. Außerdem geht sie der Frage nach, was der Unterschied vom klassischen zum hybriden Projektmanagement, welches hier angewendet wird ist und wie es möglich ist eine Supply-Chain für dieses Projekt zu erstellen.
Despite the increased attention dedicated to research on the antecedents and determinants of new venture survival in entrepreneurship, defining and capturing survival as an outcome represents a challenge in quantitative studies. This paper creates awareness for ventures being inactive while still classified as surviving based on the data available. We describe this as the ‘living dead’ phenomenon, arguing that it yields potential effects on the empirical results of survival studies. Based on a systematic literature review, we find that this issue of inactivity has not been sufficiently considered in previous new venture survival studies. Based on a sample of 501 New Technology-Based Firms, we empirically illustrate that the classification of living dead ventures into either survived or failed can impact the factors determining survival. On this basis, we contribute to an understanding of the issue by defining the ‘living dead’ phenomenon and by proposing recommendations for research practice to solve this issue in survival studies, taking the data source, the period under investigation and the sample size into account.
Text produced by entrepreneurs represents a data source in entrepreneurship research on venture performance and fund-raising success. Manual text coding of single variables is increasingly assisted or replaced by computer-aided text analysis. Yet, for the development of prediction models with several variables, such dictionary-based text analysis methods are less suitable. Natural language processing techniques are an alternative; however, the implementation is more complex and requires substantial programming skills. More work is required to understand how text analytics can advance entrepreneurship research. This study hence experiments with different artificial intelligence methods rooted in Natural Language Processing and deep learning. It uses 766 business plans to train a model for the automated measurement of transaction relations, a construct which is an indicator for new technology-based firm survival. Empirical findings show that the accuracy of construct measurement can be significantly increased with automated methods and improves with larger amounts of training data. Language complexity sets limits to the precision of automated construct measurement though. We therefore recommend a hybrid approach: making use of the inherent advantages of combining automated with human coding until the amount of training data is sufficiently large to substitute the human coding completely. The study provides insights into the applicability of different text analytics methods in entrepreneurship research and points at future research potential.
Respiratory diseases are leading causes of death and disability in the world. The recent COVID-19 pandemic is also affecting the respiratory system. Detecting and diagnosing respiratory diseases requires both medical professionals and the clinical environment. Most of the techniques used up to date were also invasive or expensive.
Some research groups are developing hardware devices and techniques to make possible a non-invasive or even remote respiratory sound acquisition. These sounds are then processed and analysed for clinical, scientific, or educational purposes.
We present the literature review of non-invasive sound acquisition devices and techniques.
The results are about a huge number of digital tools, like microphones, wearables, or Internet of Thing devices, that can be used in this scope.
Some interesting applications have been found. Some devices make easier the sound acquisition in a clinic environment, but others make possible daily monitoring outside that ambient. We aim to use some of these devices and include the non-invasive recorded respiratory sounds in a Digital Twin system for personalized health.
Matrix methods for the computation of bounds for the range of a complex polynomial and its modulus over a rectangular region in the complex plane are presented. The approach relies on the expansion of the given polynomial into Bernstein polynomials. The results are extended to multivariate complex polynomials and rational functions.
This paper examines the interdependencies of tourism, Buddhism and sustainability combining in-depth-interviews with Buddhism experts and non-participant observation in a mixed-method approach. The area under investigation is the Alpine region of Austria, Germany and Switzerland, since it is home to Asian and Western forms of Buddhism tourism alike. Results show that Buddhism tourism as a value-based activity on the one hand is not commercial, but since demand is rising, on the other hand tendencies towards more commercial forms can be observed. As a modest form of activity Buddhism tourism does not shape the landscape of the Alpine area and by its nature it incorporates sustainability.
Generalized Concatenated Codes over Gaussian and Eisenstein Integers for Code-Based Cryptography
(2021)
The code-based McEliece and Niederreiter cryptosystems are promising candidates for post-quantum public-key encryption. Recently, q-ary concatenated codes over Gaussian integers were proposed for the McEliece cryptosystem together with the one-Mannheim error channel, where the error values are limited to Mannheim weight one. Due to the limited error values, the codes over Gaussian integers achieve a higher error correction capability than maximum distance separable (MDS) codes with bounded minimum distance decoding. This higher error correction capability improves the work factor regarding decoding attacks based on information-set decoding. The codes also enable a low complexity decoding algorithm for decoding beyond the guaranteed error correction capability. In this work, we extend this coding scheme to codes over Eisenstein integers. These codes have advantages for the Niederreiter system. Additionally, we propose an improved code construction based on generalized concatenated codes. These codes extent the rate region where the work factor is beneficial compared to MDS codes. Moreover, generalized concatenated codes are more robust against structural attacks than ordinary concatenated codes.
The performance and reliability of non-volatile NAND flash memories deteriorate as the number of program/erase cycles grows. The reliability also suffers from cell to cell interference, long data retention time, and read disturb. These processes effect the read threshold voltages. The aging of the cells causes voltage shifts which lead to high bit error rates (BER) with fixed pre-defined read thresholds. This work proposes two methods that aim on minimizing the BER by adjusting the read thresholds. Both methods utilize the number of errors detected in the codeword of an error correction code. It is demonstrated that the observed number of errors is a good measure for the voltage shifts and is utilized for the initial calibration of the read thresholds. The second approach is a gradual channel estimation method that utilizes the asymmetrical error probabilities for the one-to-zero and zero-to-one errors that are caused by threshold calibration errors. Both methods are investigated utilizing the mutual information between the optimal read voltage and the measured error values.
Numerical results obtained from flash measurements show that these methods reduce the BER of NAND flash memories significantly.
Im modernen Automobilbau spielen Fussgängerschutzsysteme eine immer stärker werdende Rolle, um Verletzungen und Todesfälle bei Verkehrsunfällen mit Fussgängerbeteiligung zu reduzieren. Eines dieser Sicherheitssysteme ist die aktive Motorhaube. Durch die Verwendung von Formgedächtnislegierungen (FGL) als Aktoren können die bestehenden Systeme vereinfacht werden, wobei die gleiche Funktion durch neue Mechanismen bei reduzierter Grösse und Gewicht sowie verringerten Kosten ausgeführt werden kann. In diesem Beitrag werden nach einer Einleitung zu existierenden Systemen zur Motorhauben-Anhebung FG-Aktoren und deren potenzielle Einsatzmöglichkeiten in Automobilbau kurz vorgestellt.
This paper describes the rationale and the development of a structured digital approach for measuring corporate environmental sustainability using performance metrics.
It is impossible to imagine today's age without the preservation of our environment, not even in the corporate environment. Currently, sustainability is mostly only rudimentarily considered in companies, mostly only with written down phrases on the website. This will no longer be sufficient in the future, which is why companies should record sustainability on a numerical basis. Based on the development of a workable concept for companies, a small empirical study was carried out, which can be used to numerically measure the sustainability performance of companies. Two utility analyses were completed.
One of them was supplemented by expert interviews. Well-known practitioners from the business world were interviewed and asked for their assessment of ecological performance indicators. The result of the research is an indicator-based concept that can be applied in corporate practice to determine ecological sustainability performance.
Monitor Energiewende 2020
(2021)
Deep transformation models
(2021)
We present a deep transformation model for probabilistic regression. Deep learning is known for outstandingly accurate predictions on complex data but in regression tasks it is predominantly used to just predict a single number. This ignores the non-deterministic character of most tasks. Especially if crucial decisions are based on the predictions, like in medical applications, it is essential to quantify the prediction uncertainty. The presented deep learning transformation model estimates the whole conditional probability distribution, which is the most thorough way to capture uncertainty about the outcome. We combine ideas from a statistical transformation model (most likely transformation) with recent transformation models from deep learning (normalizing flows) to predict complex outcome distributions. The core of the method is a parameterized transformation function which can be trained with the usual maximum likelihood framework using gradient descent. The method can be combined with existing deep learning architectures. For small machine learning benchmark datasets, we report state of the art performance for most dataset and partly even outperform it. Our method works for complex input data, which we demonstrate by employing a CNN architecture on image data.
Ballistocardiography (BCG) can be used to monitor heart rate activity. Besides, the accelerometer should have high sensitivity and minimal internal noise; a low-cost approach was taken into consideration. Several measurements have been executed to determine the optimal positioning of a sensor under the mattress to obtain a signal strong enough for further analysis. A prototype for an unobtrusive accelerometer-based measurement system has been developed and tested in a conventional bed without any specific extras. The influence of the human sleep position for the output accelerometer data was tested. The obtained results indicate the potential to capture BCG signals using accelerometers. The measurement system can detect heart rate in an unobtrusive form in the home environment.
Introduction. Despite its high accuracy, polysomnography (PSG) has several drawbacks for diagnosing obstructive sleep apnea (OSA). Consequently, multiple portable monitors (PMs) have been proposed. Objective. This systematic review aims to investigate the current literature to analyze the sets of physiological parameters captured by a PM to select the minimum number of such physiological signals while maintaining accurate results in OSA detection. Methods. Inclusion and exclusion criteria for the selection of publications were established prior to the search. The evaluation of the publications was made based on one central question and several specific questions. Results. The abilities to detect hypopneas, sleep time, or awakenings were some of the features studied to investigate the full functionality of the PMs to select the most relevant set of physiological signals. Based on the physiological parameters collected (one to six), the PMs were classified into sets according to the level of evidence. The advantages and the disadvantages of each possible set of signals were explained by answering the research questions proposed in the methods. Conclusions. The minimum number of physiological signals detected by PMs for the detection of OSA depends mainly on the purpose and context of the sleep study. The set of three physiological signals showed the best results in the detection of OSA.
In today's volatile market environments, companies must be able to continuously innovate. In this context, innovation does not only refer to the development of new products or business models but often also affects the entire organization, which has to transform its structures, processes, and ways of working.Corporate entrepreneurship (CE) programs are often used by established companies to address these innovation and transformation challenges. In general, they are understood as formalized entrepreneurial activities to (1) support internal corporate ventures or (2) work with external startups. The organizational design and value creation of CE programs exhibit a high degree of heterogeneity. On the one hand, this heterogeneity makes CE programs a valuable management tool that can be used for many purposes. On the other hand, it can be seen as a reason for the current challenges that companies experience in effectively using and managing CE programs.By systematically analyzing 54 different cases in established companies in Germany, Switzerland, and Austria, this study contributes to a better understanding of the heterogeneity of CE programs. The taxonomic approach provides clearly defined types of CE programs that are distinguished according to their organizational design and the outputs they generate.
The development of home health systems can provide continuous and user-friendly monitoring of key health parameters. This project aims to create a concept for such a system, implement it on a test basis, and evaluate it. Three health areas were selected for this purpose:
Sleep, Stress, and Rehabilitation. Appropriate devices were installed in the homes of test subjects and used by them for two weeks. Besides, relevant questionnaires were completed to obtain a complete picture. Finally, the implemented system was evaluated, and the results of the conducted study showed that home health systems have great potential. However, it is necessary to consider some points to increase the usability of the system and the motivation of the users. Among others, ease of use of the equipment is of extreme importance.
Ferromagnetism is of increasing importance in the growing field of electromobility and data storage. In stable austenitic steels, the occurrence of ferromagnetism is not expected and would also interfere with many applications. However, ferromagnetism in austenitic stainless steels after low-temperature nitriding has already been shown in the past. Herein, the presence of ferromagnetism in austenitic steels is discovered after low-temperature carburization (Kolsterizing), which represents a novel and unique finding. A zone of expanded austenite is established on various austenitic stainless steels by low-temperature carburization and the respective ferromagnetism is investigated in relation to the alloy composition. The ferromagnetism occurring is determined by means of a commercial magnetoinductive sensor (Feritscope). Ferromagnetic domains are visualized by magnetic force microscopy and a ferrofluid. X-ray diffraction measurements indicate a clear difference in the lattice expansion of the different alloys. Furthermore, a different appearance of the magnetizable microstructure regions (magnetic domain structure) is detected depending on the grain orientation determined by electron backscatter diffraction (EBSD). Strongly pronounced magnetic domains show no linear lattice defects, whereas in small magnetizable areas linear lattice defects are detected by electron channeling contrast imaging and EBSD.
We compared vulnerable and fixed versions of the source code of 50 different PHP open source projects based on CVE reports for SQL injection vulnerabilities. We scanned the source code with commercial and open source tools for static code analysis. Our results show that five current state-of-the-art tools have issues correctly marking vulnerable and safe code. We identify 25 code patterns that are not detected as a vulnerability by at least one of the tools and 6 code patterns that are mistakenly reported as a vulnerability that cannot be confirmed by manual code inspection. Knowledge of the patterns could help vendors of static code analysis tools, and software developers could be instructed to avoid patterns that confuse automated tools.
With the increasing challenges of the 21st century, such as a rapidly growing population, increasing hunger and the destruction of the environment, the demand for sustainable and future-oriented ways of living is growing. To meet this demand, a residential district named Maun Science Park is being built in Botswana to develop a resilient society. In addition to the application of modern technology to optimise the use of resources, the environmentally friendly construction of the buildings is another goal of the project. This thesis investigates the prefabrication of rammed earth in terms of implementation and profitability for the Maun Science Park.
For this purpose, the specific properties, handling, as well as the application of the building material in prefabrication are first discussed.
This is followed by an investigation of how the work processes of prefabrication can be implemented in the Maun Science Park. Based on this, a profitability test is carried out using a break-even and sensitivity analysis.
The analyses showed that the investment in prefabrication is not profitable within the assumed production volume, which is due to the high fixed costs. These are primarily generated by the two main cost drivers, consisting of the new construction of the production hall and the rental of heavy construction equipment.
Lastly, recommendations for action were formulated that provide for a cost reduction in both the two main cost drivers as well as for other decisive factors.
Stadtbaukunst
(2021)
Notizen zur Stadtbaukunst
(2021)
Bedarf es heute einer institutionalisierten Stadtbaukunst? Als Gegenbewegung zur schematischen, mechanischen Stadterweiterungspraxis entwickelte sich Stadtbaukunst gegen Ende des 19. Jahrhunderts und fand in Praxis und Diskurs ihren Höhepunkt vor dem Ersten Weltkrieg. Seit einigen Jahren wird nun von verschiedenen Seiten deren Neuentdeckung und Neubewertung eingefordert. Doch die Lage heute ist eine andere als die vor über hundert Jahren. Was bedeutet das für die Idee einer Stadtbaukunst im Zusammenspiel mit Städtebau, Architektur und Stadtplanung?
Nowadays, the inexpensive memory space promotes an accelerating growth of stored image data. To exploit the data using supervised Machine or Deep Learning, it needs to be labeled. Manually labeling the vast amount of data is time-consuming and expensive, especially if human experts with specific domain knowledge are indispensable. Active learning addresses this shortcoming by querying the user the labels of the most informative images first. One way to obtain the ‘informativeness’ is by using uncertainty sampling as a query strategy, where the system queries those images it is most uncertain about how to classify. In this paper, we present a web-based active learning framework that helps to accelerate the labeling process. After manually labeling some images, the user gets recommendations of further candidates that could potentially be labeled equally (bulk image folder shift). We aim to explore the most efficient ‘uncertainty’ measure to improve the quality of the recommendations such that all images are sorted with a minimum number of user interactions (clicks). We conducted experiments using a manually labeled reference dataset to evaluate different combinations of classifiers and uncertainty measures. The results clearly show the effectiveness of an uncertainty sampling with bulk image shift recommendations (our novel method), which can reduce the number of required clicks to only around 20% compared to manual labeling.
Auslegung von Radsatzwellen unter Berücksichtigung des maximalen, dynamischen Torsionsmoments
(2021)
Der vorgestellte Bericht verdeutlicht denEinfluss des dynamischen Torsionsmomentsinfolge von selbsterregten Radsatz-Torsionsschwingungen auf den Festigkeitsnachweisvon Radsatzwellen. Durch dieanalytische Berechnung des maximalen,dynamischen Torsionsmoments werdenkausale Zusammenhänge erkennbar, diebei der Dimensionierung von Radsätzenhilfreich sind. So führt eine Vergröβerungdes Radsatzwellendurchmessers aufgrundder zunehmenden Torsionssteifigkeitzwar zu höheren Momenten, bewirktaber gleichzeitig eine deutlich niedrigereVergleichsspannung. Durch gröβereDurchmesser der Radsatzwelle ist, infolgegeringerer Fugendrücke, allerdings auchmit einer Schwächung der Pressverbändezu rechnen. In jedem Fall sind im Hinblickauf den Festigkeitsnachweis kleine Radradienvorteilhaft. Sollten Radradius undRadsatzwellendurchmesser nicht optimiertwerden können, kann zur weiteren Absicherungdes Festigkeitsnachweises derWerkstoff EA4T verwendet werden.
Die vorgestellte analytische Berechnungsmethode führt, unter Berücksichtigung desKraftschlusses, der Radsatzdimensionierungund der Dämpfungseigenschaft des Antriebssystems, zu einem konservativ berechnetendynamischen Torsionsmoment.Die ermittelten Abweichungen zeigenleicht gröβere Werte gegenüber der Messungund über einen breiten Parameterbereichtendenziell gröβere Werte gegenüber der Simulation. Demnach stellt die Methodeeinen pragmatischen Ansatz dar, dasmaximale, dynamische Torsionsmomentfür die Auslegung von Radsatzwelle ausreichendkonservativ zu berechnen.