@article{KowalewskiBragardHueningetal.2023, author = {Kowalewski, Paul and Bragard, Michael and H{\"u}ning, Felix and De Doncker, Rik W.}, title = {An inexpensive Wiegand-sensor-based rotary encoder without rotating magnets for use in electrical drives}, series = {IEEE Transactions on Instrumentation and Measurement}, volume = {72}, journal = {IEEE Transactions on Instrumentation and Measurement}, publisher = {IEEE}, address = {New York}, issn = {0018-9456 (Print)}, doi = {10.1109/TIM.2023.3326166}, pages = {10 Seiten}, year = {2023}, abstract = {This paper introduces an inexpensive Wiegand-sensor-based rotary encoder that avoids rotating magnets and is suitable for electrical-drive applications. So far, Wiegand-sensor-based encoders usually include a magnetic pole wheel with rotating permanent magnets. These encoders combine the disadvantages of an increased magnet demand and a limited maximal speed due to the centripetal force acting on the rotating magnets. The proposed approach reduces the total demand of permanent magnets drastically. Moreover, the rotating part is manufacturable from a single piece of steel, which makes it very robust and cheap. This work presents the theoretical operating principle of the proposed approach and validates its benefits on a hardware prototype. The presented proof-of-concept prototype achieves a mechanical resolution of 4.5 ° by using only 4 permanent magnets, 2Wiegand sensors and a rotating steel gear wheel with 20 teeth.}, language = {en} } @inproceedings{GrundAltherr2023, author = {Grund, Raphael M. and Altherr, Lena}, title = {Development of an open source energy disaggregation tool for the home automation platform Home Assistant}, series = {Tagungsband AALE 2023 : mit Automatisierung gegen den Klimawandel}, booktitle = {Tagungsband AALE 2023 : mit Automatisierung gegen den Klimawandel}, editor = {Reiff-Stephan, J{\"o}rg and J{\"a}kel, Jens and Schwarz, Andr{\´e}}, publisher = {le-tex publishing services GmbH}, address = {Leipzig}, isbn = {978-3-910103-01-6}, doi = {10.33968/2023.02}, pages = {11 -- 20}, year = {2023}, abstract = {In order to reduce energy consumption of homes, it is important to make transparent which devices consume how much energy. However, power consumption is often only monitored aggregated at the house energy meter. Disaggregating this power consumption into the contributions of individual devices can be achieved using Machine Learning. Our work aims at making state of the art disaggregation algorithms accessibe for users of the open source home automation platform Home Assistant.}, language = {en} } @inproceedings{WittigRuettersBragard2024, author = {Wittig, M. and R{\"u}tters, Ren{\´e} and Bragard, Michael}, title = {Application of RL in control systems using the example of a rotatory inverted pendulum}, series = {Tagungsband AALE 2024 : Fit f{\"u}r die Zukunft: praktische L{\"o}sungen f{\"u}r die industrielle Automation}, booktitle = {Tagungsband AALE 2024 : Fit f{\"u}r die Zukunft: praktische L{\"o}sungen f{\"u}r die industrielle Automation}, editor = {Reiff-Stephan, J{\"o}rg and J{\"a}kel, Jens and Schwarz, Andr{\´e}}, publisher = {le-tex publishing services GmbH}, address = {Leipzig}, isbn = {978-3-910103-02-3}, doi = {10.33968/2024.53}, pages = {241 -- 248}, year = {2024}, abstract = {In this paper, the use of reinforcement learning (RL) in control systems is investigated using a rotatory inverted pendulum as an example. The control behavior of an RL controller is compared to that of traditional LQR and MPC controllers. This is done by evaluating their behavior under optimal conditions, their disturbance behavior, their robustness and their development process. All the investigated controllers are developed using MATLAB and the Simulink simulation environment and later deployed to a real pendulum model powered by a Raspberry Pi. The RL algorithm used is Proximal Policy Optimization (PPO). The LQR controller exhibits an easy development process, an average to good control behavior and average to good robustness. A linear MPC controller could show excellent results under optimal operating conditions. However, when subjected to disturbances or deviations from the equilibrium point, it showed poor performance and sometimes instable behavior. Employing a nonlinear MPC Controller in real time was not possible due to the high computational effort involved. The RL controller exhibits by far the most versatile and robust control behavior. When operated in the simulation environment, it achieved a high control accuracy. When employed in the real system, however, it only shows average accuracy and a significantly greater performance loss compared to the simulation than the traditional controllers. With MATLAB, it is not yet possible to directly post-train the RL controller on the Raspberry Pi, which is an obstacle to the practical application of RL in a prototyping or teaching setting. Nevertheless, RL in general proves to be a flexible and powerful control method, which is well suited for complex or nonlinear systems where traditional controllers struggle.}, language = {en} } @article{SchoppRohrbachLangeretal.2024, author = {Schopp, Christoph and Rohrbach, Felix and Langer, Luc and Heuermann, Holger}, title = {Detection of welding wire length by active S11 measurement}, series = {IEEE Transactions on Plasma Science}, journal = {IEEE Transactions on Plasma Science}, number = {Early Access}, publisher = {IEEE}, issn = {0093-3813 (Print)}, doi = {10.1109/TPS.2024.3356659}, pages = {1 -- 6}, year = {2024}, abstract = {A novel method to determine the extruded length of a metallic wire for a directed energy deposition (DED) process using a microwave (MW) plasma jet with a straight-through wire feed is presented. The method is based on the relative comparison of the measured frequency response obtained by the large-signal scattering parameter (Hot-S) technique. In the practical working range, repeatability of less than 6\% for a nonactive plasma and 9\% for the active plasma state is found. Measurements are conducted with a focus on a simple solution to decrease the processing time and reduce the integration time of the process into the existing hardware. It is shown that monitoring a single frequency for magnitude and phase changes is sufficient to achieve good accuracy. A combination of different measurement values to determine the length is possible. The applicability to different diameter of the same material is shown as well as a contact detection of the wire and metallic substrate.}, language = {en} } @article{TurdumamatovBeldaHeuermann2024, author = {Turdumamatov, Samat and Belda, Aljoscha and Heuermann, Holger}, title = {Shaping a decoupled atmospheric pressure microwave plasma with antenna structures, Maxwell's equations, and boundary conditions}, series = {IEEE Transactions on Plasma Science}, journal = {IEEE Transactions on Plasma Science}, number = {Early Access}, publisher = {IEEE}, issn = {0093-3813 (Print)}, doi = {10.1109/TPS.2024.3383589}, pages = {1 -- 9}, year = {2024}, abstract = {This article addresses the need for an innovative technique in plasma shaping, utilizing antenna structures, Maxwell's laws, and boundary conditions within a shielded environment. The motivation lies in exploring a novel approach to efficiently generate high-energy density plasma with potential applications across various fields. Implemented in an E01 circular cavity resonator, the proposed method involves the use of an impedance and field matching device with a coaxial connector and a specially optimized monopole antenna. This setup feeds a low-loss cavity resonator, resulting in a high-energy density air plasma with a surface temperature exceeding 3500 o C, achieved with a minimal power input of 80 W. The argon plasma, resembling the shape of a simple monopole antenna with modeled complex dielectric values, offers a more energy-efficient alternative compared to traditional, power-intensive plasma shaping methods. Simulations using a commercial electromagnetic (EM) solver validate the design's effectiveness, while experimental validation underscores the method's feasibility and practical implementation. Analyzing various parameters in an argon atmosphere, including hot S -parameters and plasma beam images, the results demonstrate the successful application of this technique, suggesting its potential in coating, furnace technology, fusion, and spectroscopy applications.}, language = {en} } @incollection{SchneiderWisselinkCzarneckietal.2024, author = {Schneider, Dominik and Wisselink, Frank and Czarnecki, Christian and N{\"o}lle, Nikolai}, title = {Benefits and framework conditions for information-driven business models concerning the Internet of Things}, series = {Digitalization in companies}, booktitle = {Digitalization in companies}, publisher = {Springer}, address = {Wiesbaden}, isbn = {978-3-658-39093-8 (Print)}, doi = {10.1007/978-3-658-39094-5_5}, pages = {59 -- 75}, year = {2024}, abstract = {In the context of the increasing digitalization, the Internet of Things (IoT) is seen as a technological driver through which completely new business models can emerge in the interaction of different players. Identified key players include traditional industrial companies, municipalities and telecommunications companies. The latter, by providing connectivity, ensure that small devices with tiny batteries can be connected almost anywhere and directly to the Internet. There are already many IoT use cases on the market that provide simplification for end users, such as Philips Hue Tap. In addition to business models based on connectivity, there is great potential for information-driven business models that can support or enhance existing business models. One example is the IoT use case Park and Joy, which uses sensors to connect parking spaces and inform drivers about available parking spaces in real time. Information-driven business models can be based on data generated in IoT use cases. For example, a telecommunications company can add value by deriving more decision-relevant information - called insights - from data that is used to increase decision agility. In addition, insights can be monetized. The monetization of insights can only be sustainable, if careful attention is taken and frameworks are considered. In this chapter, the concept of information-driven business models is explained and illustrated with the concrete use case Park and Joy. In addition, the benefits, risks and framework conditions are discussed.}, language = {en} } @incollection{IbanezSanchezWolf2020, author = {Ibanez-Sanchez, Gema and Wolf, Martin R.}, title = {Interactive Process Mining-Induced Change Management Methodology for Healthcare}, series = {Interactive Process Mining in Healthcare}, booktitle = {Interactive Process Mining in Healthcare}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-53993-1 (Online)}, doi = {10.1007/978-3-030-53993-1_16}, pages = {267 -- 293}, year = {2020}, abstract = {The adoption of the Digital Health Transformation is a tremendous paradigm change in health organizations, which is not a trivial process in reality. For that reason, in this chapter, it is proposed a methodology with the objective to generate a changing culture in healthcare organisations. Such a change culture is essential for the successful implementation of any supporting methods like Interactive Process Mining. It needs to incorporate (mostly) new ways of team-based and evidence-based approaches for solving structural problems in a digital healthcare environment.}, language = {en} } @inproceedings{ZaehlBiewendtWolfetal.2022, author = {Z{\"a}hl, Philipp M. and Biewendt, Marcel and Wolf, Martin R. and Eggert, Mathias}, title = {Requirements for competence developing games in the environment of SE Competence Development}, series = {AKWI-Tagungsband zur 35. AKWI-Jahrestagung}, booktitle = {AKWI-Tagungsband zur 35. AKWI-Jahrestagung}, publisher = {GITO}, address = {Berlin}, isbn = {978-3-95545-409-8}, doi = {10.30844/AKWI_2022_05}, pages = {73 -- 88}, year = {2022}, abstract = {Many of today's factors make software development more and more complex, such as time pressure, new technologies, IT security risks, et cetera. Thus, a good preparation of current as well as future software developers in terms of a good software engineering education becomes progressively important. As current research shows, Competence Developing Games (CDGs) and Serious Games can offer a potential solution. This paper identifies the necessary requirements for CDGs to be conducive in principle, but especially in software engineering (SE) education. For this purpose, the current state of research was summarized in the context of a literature review. Afterwards, some of the identified requirements as well as some additional requirements were evaluated by a survey in terms of subjective relevance.}, language = {en} } @inproceedings{KoenigWolf2018, author = {K{\"o}nig, Johannes Alexander and Wolf, Martin R.}, title = {Cybersecurity awareness training provided by the competence developing game GHOST}, series = {ACHI 2018 : The Eleventh International Conference on Advances in Computer-Human Interactions}, booktitle = {ACHI 2018 : The Eleventh International Conference on Advances in Computer-Human Interactions}, isbn = {978-1-61208-616-3}, pages = {81 -- 87}, year = {2018}, abstract = {This paper introduces a Competence Developing Game (CDG) for the purpose of a cybersecurity awareness training for businesses. The target audience will be discussed in detail to understand their requirements. It will be explained why and how a mix of business simulation and serious game meets these stakeholder requirements. It will be shown that a tablet and touchscreen based approach is the most suitable solution. In addition, an empirical study will be briefly presented. The study was carried out to examine how an interaction system for a 3D-tablet based CDG has to be designed, to be manageable for non-game experienced employees. Furthermore, it will be explained which serious content is necessary for a Cybersecurity awareness training CDG and how this content is wrapped in the game}, language = {en} } @incollection{EggertZaehlWolfetal.2023, author = {Eggert, Mathias and Z{\"a}hl, Philipp M. and Wolf, Martin R. and Haase, Martin}, title = {Applying leaderboards for quality improvement in software development projects}, series = {Software Engineering for Games in Serious Contexts}, booktitle = {Software Engineering for Games in Serious Contexts}, editor = {Cooper, Kendra M.L. and Bucchiarone, Antonio}, publisher = {Springer}, address = {Cham}, isbn = {978-3-031-33337-8 (Print)}, doi = {10.1007/978-3-031-33338-5_11}, pages = {243 -- 263}, year = {2023}, abstract = {Software development projects often fail because of insufficient code quality. It is now well documented that the task of testing software, for example, is perceived as uninteresting and rather boring, leading to poor software quality and major challenges to software development companies. One promising approach to increase the motivation for considering software quality is the use of gamification. Initial research works already investigated the effects of gamification on software developers and come to promising. Nevertheless, a lack of results from field experiments exists, which motivates the chapter at hand. By conducting a gamification experiment with five student software projects and by interviewing the project members, the chapter provides insights into the changing programming behavior of information systems students when confronted with a leaderboard. The results reveal a motivational effect as well as a reduction of code smells.}, language = {en} }