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Managing an ever-growing number of requirements is a time consuming and highly complex activity in product development projects. With the rise of Artificial Intelligence (AI) in the last decades, algorithms are now capable of supporting Requirements Engineering (RE) tasks. The algorithm’s ability to intelligently process natural language data as well as the application in RE have been published extensively. In established RE processes however, it is often unclear, where AI algorithms can be utilized. The result is a significant imbalance between state-of-the-art AI algorithms and their application rates in real RE processes. One of the reasons is, that current models of RE processes aren’t able to convey the needed information for the identification of suitable tasks. Therefore, this paper aims to provide a framework of finite and standardized process steps with a data processing-oriented perspective, that can be used to systematically identify the points in the RE processes where AI algorithms can be applied. With the standardized process steps of this framework, established RE processes can be abstracted and expressed in a way that is compatible with the scope of AI algorithms. Due to the finite number of standardized process steps, libraries of suitable AI algorithms for the defined process steps can be built, so that their applicability can be efficiently assessed. The presented framework was developed collaboratively during a research project with industry participation.

Exploring the interaction of light with time-varying media is an intellectual challenge that, in addition to fundamental aspects, provides a pathway to multiple promising applications. Time modulation constitutes here a fundamental handle to control light on entirely different grounds. That holds particularly for complex systems simultaneously structured in space and time. However, a realistic description of time-varying materials requires considering their material dispersion. The combination thereof has barely been considered but is crucial since dispersion accompanies materials suitable for dynamic modulation. As a canonical scattering problem from which many general insights can be obtained, a self-consistent analytical theory of light scattering by a sphere made from a time-varying material exemplarily assumed to have a Lorentzian dispersion is developed and applied. The eigensolutions of Maxwell's equations in the bulk are discussed and a dedicated Mie theory is presented. The proposed theory is verified with full-wave simulations. Peculiar effects are disclosed, such as energy transfer from the time-modulation subsystem to the electromagnetic field, amplifying carefully structured incident fields. Since many phenomena can be studied on analytical grounds with the proposed formalism, it represents an indispensable tool that enables exploration of electromagnetic phenomena in time-varying and spatially structured finite objects of other geometries.

This paper presents an approach to recognize problem related entities in production chats to structure the informal communication and include arising problems into digital shop floor management and its assistance functions. Requirements are derived from employee surveys, company surveys and from union experts. Based on annotated data that has been collected during a simulation in the process learning factory ``Center for Industrial Productivity'' (CiP) at the Technical University of Darmstadt, approaches for identifying and structuring problem recognition and solution in production chat logs are evaluated. Finally, a system design is suggested to utilize such an entity recognition in an industrial chat application to improve digital shop floor management systems.

This paper aims to develop concepts how digital shop floor management (dSFM) can be further enhanced by natural language processing (NLP) to bring a higher value to the shop floor team and decision makers. Based on the literature review on these two fields several valuable application of NLP in dSFM are theorized: recommender engines to improve knowledge management, text clustering to identify frequent problems, voice assistants to ease the interaction with the data base, chat log extraction to fill the database with unstructured written text from chats and spellcheck as well as auto fill to improve data quality. To show the feasibility for NLP in dSFM in industry, a case study for the document clustering is presented: A digital ticket system for shop floor issues used for two years and containing 2,735 entries is analysed with the “Graph”-feature from Elasticsearch to find the most frequent terms and intersections in the described problems. The approach is accurate, quick and detailed and will be established in the company and performed monthly.

Der Beitrag untersucht den Einsatz von IoT-Technologien in japanischen Automobilunternehmen. Auf der Basis von Fallstudien in sieben Unternehmen wird mit der Gemba-Digitalisierung ein Modus identifiziert, der auch für deutsche Unternehmen und Digitalisierungsexperten sowie die Forschung hierzulande von Interesse ist. Kennzeichnend für die Gemba-Digitalisierung sind die Shopfloor-Orientierung der Digitalisierungsaktivitäten, ihr pragmatischer Low-Cost-Ansatz, der Respekt für das praktische Wissen der Produktionsarbeiter und die Einbettung in die in japanischen Unternehmen verbreitete Gemba-Kultur The contribution analyzes the use of IoT-technologies in Japanese automotive companies. Based on seven company case studies, a specific mode of the introduction of advanced technologies is identified, namely gemba digitalisation. Gemba digitalisation is characterized by the shopfloor orientation of digitalisation activities, its pragmatic low cost approach, its respect for the practical knowledge of production workers and its support for the Gemba orientation deeply embedded in the company culture of many Japanese companies.

The functionalities of BiFeO3-based magnetoelectric multiferroic heterostructures rely on the controlled manipulation of their ferroelectric domains and of the corresponding net in-plane polarization, as this aspect guides the voltage-controlled magnetic switching. Chemical substitution has emerged as a key to push the energy dissipation of the BiFeO3 into the attojoule range but appears to result in a disordered domain configuration. Using non-invasive optical second-harmonic generation on heavily La-substituted BiFeO3 films, it is shown that a weak net in-plane polarization remains imprinted in the pristine films despite the apparent domain disorder. It is found that this ingrained net in-plane polarization can be trained with out-of-plane electric fields compatible with applications. Operando studies on capacitor heterostructures treated in this way show the full restoration of the domain configuration of pristine BiFeO3 along with a giant net in-plane polarization enhancement. Thus, the experiments reveal a surprising robustness of the net in-plane polarization of BiFeO3 against chemical modification, an important criterion in ongoing attempts to integrate magnetoelectric materials into energy-efficient devices., Advanced Materials, 33 (52), ISSN:0935-9648, ISSN:1521-4095

Even with digital shop floor management systems on the rise the knowledge about previously solved problems in production is not shared and used valuably. This paper aims to evaluate if recommender engines can be utilized in digital shop floor management systems to overcome this gap. Therefore, in a first step interviews are conducted to identify requirements from an industry perspective. Based on those, a system for problem solving management with an integrated content-based recommender engine to enhance knowledge management on the shop floor is designed, implemented and tested for its functionality. The evaluation of the quality of the recommendations as well as the quantified industry feedback give promising results and indicate future research and development steps.

We discuss a class of stochastic second-order PDEs in one space-dimension with an inner boundary moving according to a possibly nonlinear, Stefan-type condition. We show that proper separation of phases is attained, i.e., the solution remains negative on one side and positive on the other side of the moving interface, when started with the appropriate initial conditions. To extend results from deterministic settings to the stochastic case, we establish a Wong–Zakai-type approximation. After a coordinate transformation, the problems are reformulated and analyzed in terms of stochastic evolution equations on domains of fractional powers of linear operators.

For next-generation technology, magnetic systems are of interest due to the natural ability to store information and, through spin transport, propagate this information for logic functions. Controlling the magnetization state through currents has proven energy inefficient. Multiferroic thin-film heterostructures, combining ferroelectric and ferromagnetic orders, hold promise for energy efficient electronics. The electric field control of magnetic order is expected to reduce energy dissipation by 2–3 orders of magnitude relative to the current state-of-the-art. The coupling between electrical and magnetic orders in multiferroic and magnetoelectric thin-film heterostructures relies on interfacial coupling though magnetic exchange or mechanical strain and the correlation between domains in adjacent functional ferroic layers. We review the recent developments in electrical control of magnetism through artificial magnetoelectric heterostructures, domain imprint, emergent physics and device paradigms for magnetoelectric logic, neuromorphic devices, and hybrid magnetoelectric/spin-current-based applications. Finally, we conclude with a discussion of experiments that probe the crucial dynamics of the magnetoelectric switching and optical tuning of ferroelectric states towards all-optical control of magnetoelectric switching events., Physical Sciences Reviews, 6 (2)

ZusammenfassungTeamWork 4.0 beschäftigt sich mit der Einführung von digitalen Assistenzsystemen und ihren Rückwirkungen auf industrielle Gruppen- und Teamarbeit. Die in den Verbundunternehmen entwickelten und erprobten Assistenzsysteme adressieren jeweils Shopfloor-Herausforderungen, die in industriellen KMU weit verbreitet sind: Das bei der Mahr GmbH entwickelte digitale Dokumentationssystem macht die aus der kundenindividuellen Maschinenfertigung erwachsende Komplexität an Dokumentationen beherrschbar, die bei der Homag AG entwickelte KVP-App erleichtert die Beteiligung der Mitarbeitenden an Verbesserungsprozessen und das bei der Voith AG eingeführte Shopfloor Management-System erhöht die Transparenz von Problemlösungen. Der von TeamWork 4.0 verfolgte beteiligungsorientierte Ansatz stellt sicher, dass die Assistenzsysteme in der Belegschaft über eine hohe Akzeptanz verfügen und die Weiterentwicklung der bestehenden Gruppen- und Teamarbeit unterstützen.

Among N = 165 14–22-year-old bearers of celiac disease (CD), the German-based study examined if participation in camps for children with CD is related to higher CD-related quality of life (CD-QoL); N = 48 of the study participants attended at least one camp. Camp participation was found to be related to higher CD-QoL, an effect mediated by having more friends with CD and by perceiving higher social support. Camp participation was also associated with higher illness acceptance and lower anxiety. Results show the potential benefits of recreational activities in CD treatment, to be further examined in experimental research.

Digitalization and Industry 4.0 have a strong impact on today’s production environment. The established methods of lean production are also affected and can be further improved through new technologies. The following paper addresses how and whether digitalization enhances shop floor management (SFM) as a key element of the philosophy of lean production. Based on the Darmstadt shop floor management model, it will be discussed where digitalization is expected to be value-adding or bearing risks in which elements of SFM and how the transition to a digital system opens up new possibilities. The potential of digital SFM systems are evaluated through a literature review and interviews with experts. Based on the results a digital SFM prototype is evaluated and further developed and applied to the learning factory Center for industrial Productivity (CiP) and its underlying process control system. The versatile environment of the learning factory is consequently being used for evaluation of digital SFM in different working situations like manual labor or machining.

Memory and logic devices that encode information in magnetic domains rely on the controlled injection of domain walls to reach their full potential. In this work, we exploit the chiral coupling induced by the Dzyaloshinskii-Moriya interaction between in-plane and out-of-plane magnetized regions of a Pt/Co/AlO\textsubscript{x} trilayer in combination with current-driven spin-orbit torques to control the injection of domain walls into magnetic conduits. We demonstrate that the current-induced domain nucleation is strongly inhibited for magnetic configurations stabilized by the chiral coupling and promoted for those that have the opposite chirality. These configurations allow for efficient domain wall injection using current densities of the order of $4\times$\SI{e11}{A m^{-2}}, which are lower than those used in other injection schemes. Furthermore, by setting the orientation of the in-plane magnetization using an external field, we demonstrate the use of a chiral domain wall injector to create a controlled sequence of alternating domains in a racetrack structure driven by a steady stream of unipolar current pulses.

Motivated by applications in economics and finance, in particular to the modeling of limit order books, we study a class of stochastic second-order PDEs with non-linear Stefan-type boundary interaction. To solve the equation we transform the problem from a moving boundary problem into a stochastic evolution equation with fixed boundary conditions. Using results from interpolation theory we obtain existence and uniqueness of local strong solutions, extending results of Kim, Zheng and Sowers. In addition, we formulate conditions for existence of global solutions and provide a refined analysis of possible blow-up behavior in finite time., 34 pages

We establish weak convergence rates for noise discretizations of a wide class of stochastic evolution equations with non-regularizing semigroups and additive or multiplicative noise. This class covers the nonlinear stochastic wave, HJMM, stochastic Schr\"odinger and linearized stochastic Korteweg-de Vries equation. For several important equations, including the stochastic wave equation, previous methods give only suboptimal rates, whereas our rates are essentially sharp., Comment: 26 pages, minor revision