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In daily life, people tend to use mental shortcuts to simplify and speed up their decision-making processes. A halo effect exists if the impression created by a dominant attribute influences how other attributes of an object or subject are judged. It involves a cognitive bias that leads to distorted assessments. However, the halo effect has barely been researched in a sports-related context, although it can substantially contribute to understanding how sport fans think and behave. The objective of this paper is to answer the question that is of interest for both theory and practice of sports marketing: Is there a halo effect in sports? Does the sporting success or failure of a professional soccer team radiate or even outshine other sports related and non-sports aspects and influence or distort how the club is perceived by its fans? Fans of six soccer clubs selected from the first German soccer league Bundesliga were interviewed. This paper presents the results of an empirical study based on a data set consisting of a total of 4,180 cases. The results of the analyses substantiate the distortion of the fans’ perception with regard to a very diverse range of aspects that is triggered by the sporting success or failure of their favorite club.
The 21st century: an era where emojis and hashtags find their way into every sentence, where taking selfies, live tweeting and mining bitcoin are the norm, and where Insta-culture dictates what we say and do. This is the era into which the digital native was born. With so many changes in every aspect of our lives, how is it that one of the most influential aspects, our education, has remained unchanged? Our education system not only fails to appeal to today’s students, but more importantly, it fails to equip them with the skills required in the 21st Century. It is thus of no surprise that industries feel graduates entering the workplace lack skills in critical thinking, problem solving and self-directed learning. AI, machine learning and big data: Tools and mechanisms we so eagerly incorporate to create smart factories yet are hesitant to use elsewhere. Gamification and games have shown great results in education and training; with most research suggesting a stronger focus on personalization and adaptation. When combined with analytics and machine learning, the potential of games is yet to be realized. A real-time adaptive game would not only always present an appropriate degree of challenge for the individual but would allow for a shift in focus from the recitation of facts, to the application of information filtered to solve the particular problem at hand. South Africa, a country faced with a severe skills gap, could benefit greatly from games. If used correctly, they may just offer a desperately needed contribution toward equipping both current and future employees with the skills needed to survive in the 21st century. This paper explores the feasibility of using such games for enhanced knowledge dissemination and the upskilling of the workforce.
Artificial adipose tissue (AT) constructs are urgently needed to treat severe wounds, to replace removed tissue, or for the use as in vitro model to screen for potential drugs or study metabolic pathways. The clinical translation of products is mostly prevented by the absence of a vascular component that would allow a sustainable maintenance and an extension of the construct to a relevant size. With this study, we aimed to evaluate the suitability of a novel material based on bacterial cellulose (CBM) on the defined adipogenic differentiation of human adipose-derived stem cells (ASCs) and the maintenance of the received adipocytes (diffASCs) and human microvascular endothelial cells (mvECs) in mono- and coculture. A slight acceleration of adipogenic differentiation over regular tissue culture polystyrene (TCPS) was seen on CBM under defined conditions, whereas on the maintenance of the generated adipocytes, comparable effects were detected for both materials. CBM facilitated the formation of vascular like structures in monoculture of mvECs, which was not observed on TCPS. By contrast, vascular-like structures were detected in CBM and TCPS in coculture by the presence of diffASCs. Concluding, CBM represents a promising material in vascularized AT engineering with the potential to speed up and simplify the in vitro setup of engineered products.
In smart factories, maintenance is still an important aspect to safeguard the performance of their production. Especially in case of failures of machine components diagnosis is a time-consuming task. This paper presents an approach for a cyber-physical failure management system, which uses information from machines such as programmable logic controller or sensor data and IT systems to support the diagnosis and repairing process. Key element is a model combining the different information sources to detect deviations and to determine a probable failed component. Furthermore, the approach is prototypically implemented for leakage detection in compressed air networks.
Type 1 diabetes is a chronic and a life threatening disease: an adjusted treatment and a proper management of the disease are crucial to prevent or delay the complications of diabetes. Although during the last decade the development of the artificial pancreas has presented great advances in diabetes care, the multiple daily injections therapy still represents the most widely used treatment option for type 1 diabetes. This work presents the proposal and first development stages of an application focused on guiding patients using the continuous glucose monitors and smart pens together with insulin and carbohydrates recommendations. Our proposal aims to develop a platform to integrate a series of innovative machine learning models and tools rigorously tested together with the use of the latest IoT devices to manage type 1 diabetes. The resulting system actually closes the loop, like the artificial pancreas, but in an intermittent way.
Purpose – Many start-ups are in search of cooperation partners to develop their innovative business models. In response, incumbent firms are introducing increasingly more cooperation systems to engage with startups. However, many of these cooperations end in failure. Although qualitative studies on cooperation models have tried to improve the effectiveness of incumbent start-up strategies, only a few have empirically examined start-up cooperation behavior. The paper aims to discuss these issues.
Design/methodology/approach – Drawing from a series of qualitative and quantitative studies. The scale dimensions are identified on an interview based qualitative study. Following workshops and questionnaire-based studies identify factors and rank them. These ranked factors are then used to build a measurement scale that is integrated in a standardized online questionnaire addressing start-ups. The gathered data are then analyzed using PLS-SEM.
Findings – The research was able to build a multi-item scale for start-ups cooperation behavior. This scale can be used in future research. The paper also provides a causal analysis on the impact of cooperation behavior on start-up performance. The research finds, that the found dimensions are suitable for measuring cooperation behavior. It also shows a minor positive effect on start-up’s performance.
Originality/value – The research fills the gap of lacking empirical research on the cooperation between start-ups and established firms. Also, most past studies focus on organizational structures and their performance when addressing these cooperations. Although past studies identified the start-ups behavior as a relevant factor, no empirical research has been conducted on the topic yet.
A fully passive RFID temperature sensor SoC with an accuracy of ±0.4 ◦C (3σ) from 0 ◦C to 125 ◦C
(2019)
This paper presents a fully passive 13.56 -MHz RFID temperature sensor system-on-chip. Its power management unit operates over a large temperature range using a zero temperature coefficient bias source. On-chip temperature sensing is accomplished with low-voltage, low-power CMOS circuitry, and time-domain signal processing. Two readout commands have been defined to study supply noise sensitivity: 1) standard readout, where just a single set of data is transferred to the reader and 2) serial readout, where several sets of data are sent one after the other to the reader. With the standard readout command, the sensor suffers from interference from the RFID command packet and outputs interference as well, while the sensor outputs no interference with the serial readout command. Measurements show that sensor resolution with serial readout is improved by a factor of approximately 16 compared to standard readout. The chip was fabricated in a standard 0.35-μm CMOS technology and chip-on-board mounted to a tuned RFID transponder coil on an aluminum core FR4 PCB substrate. Real time wireless temperature sensing has been demonstrated with a commercial HF RFID reader. With a two-point calibration, the SoC achieves a 3σ sensing accuracy of ±0.4 ◦C from 0◦C to 125 ◦C.
In this paper, we address the novel EDP (Expert Design Plan) principle for procedural design automation of analog integrated circuits, which captures the knowledge-based design strategy of human circuit designers in an executable script, making it reusable. We present the EDP Player, which enables the creation and execution of EDPs for arbitrary circuits in the Cadence® Virtuoso® Design Environment. The tool provides a generic version of an instruction set, called EDPL (EDPLanguage), enabling emulation of a typical manual analog sizing flow. To automate the design of a Miller Operational Amplifier and to create variants of a Smart Power IC, several EDPs were implemented using this tool. Employing these EDPs leads to a strong reduction of design time without compromising design quality or reliability.
Rapidly growing population and increasing amount of shipments induced by the e-commerce are two of the main reasons for the constantly rising urban freight traffic. Cities are therefore overwhelmed by a growing stream of goods and the available infrastructure, shared between people and goods traffic, often reached its maximum capacity. Phenomena such as traffic congestion, pollution and lack of space are direct consequences of this trend and their impact on the quality of life in the city is not negligible. City administrations are keen to evaluate innovative city logistics concepts and adopt alternative solutions, to overcome the challenges posed by such a dynamic environment, constrained in existing infrastructure. In this paper, a heuristic method based on the utility analysis is presented. Thanks to a modular approach accounting for stakeholders´ requirements, possible different scenarios and available technologies, the development of new city logistic concepts is supported. The proposed method is then applied to a case study concerning the city of Reutlingen (Germany). Results are presented and a brief discussion leads to the conclusion.
This paper presents an approach for the implementation of a modular and scalable power electronics device for controlling electric drives in the field of electric vehicles using wide bandgap semiconductor devices. The main idea is to achieve the required output currents or voltages by connecting adequately designed hardware modules in parallel or in series. This particular design is based on the fact that the single modules generate a continuous and specified output voltage from a given dc voltage, e.g. an intermediate circuit or battery voltage. The main benefit is, that different current or voltage requirements can be satisfied based on a single module thus decreasing development and production costs. The current paper focuses on the connection in parallel of such modules. A control architecture is illustrated and a first proof of concept is given.
While several service-based maintainability metrics have been proposed in the scientific literature, reliable approaches to automatically collect these metrics are lacking. Since static analysis is complicated for decentralized and technologically diverse microservice-based systems, we propose a dynamic approach to calculate such metrics from runtime data via distributed tracing. The approach focuses on simplicity, extensibility, and broad applicability. As a first prototype, we implemented a Java application with a Zipkin integrator, 23 different metrics, and five export formats. We demonstrated the feasibility of the approach by analyzing the runtime data of an example microservice based system. During an exploratory study with six participants, 14 of the 18 services were invoked via the system’s web interface. For these services, all metrics were calculated correctly from the generated traces.
A novel brushless excitation concept for synchronous machines with a rotating power converter is proposed in this paper. The concept does not need an auxiliary winding or any other modification to the machine structure apart from an inverter with a DC link capacitor and a controller on the rotor. The power required for the rotor excitation is provided by injecting harmonics into the stator winding. Thus, a voltage in the field coil is induced. The rotor inverter is controlled such that the alternating current charges the DC link capacitor. At the same time the inverter supplies the DC field current to the field coil. The excitation concept is first developed in theory, then presented using an analytical model and FEA, and lastly investigated with a prelimininary experimental setup.
A new two-dimensional fluorescence sensor system was developed for in-line monitoring of mammalian cell cultures. Fluorescence spectroscopy allows for the detection and quantification of naturally occurring intra- and extracellular fluorophores in the cell broth. The fluorescence signals correlate the the cells' current redox state and other relevant process parameters. Cell culture pretests with twelve different excitation wavelengths showed that only three wavelengths account for a vast majority of spectral variation. Accordingly, the newly developed device utilizes three high-power LEDs as excitation sources in combination with a back-thinned CCD-spectrometer for fluorescence detection.
Additive manufacturing is a key technology which applies the ideas of Industry 4.0 in order to enable the production of personalized and highly customized products economically. Especially small and medium sized companies often lack the competence and experience to evaluate objectively and profoundly the potential of additive manufacturing technologies in small and medium sized companies. Furthermore, the method has been validated in a small medical technology company evaluating the additive manufacturing potential of an existing surgery tool.
The cloud evolved into an attractive execution environment for parallel applications from the High Performance Computing (HPC) domain. Existing research recognized that parallel applications require architectural refactoring to benefit from cloud-specific properties (most importantly elasticity). However, architectural refactoring comes with many challenges and cannot be applied to all applications due to fundamental performance issues. Thus, during the last years, different cloud migration strategies have been considered for different classes of parallel applications. In this paper, we provide a survey on HPC cloud migration research. We investigate on the approaches applied and the parallel applications considered. Based on our findings, we identify and describe three cloud migration strategies.
Size and function of bioartificial tissue models are still limited due to the lack of blood vessels and dynamic perfusion for nutrient supply. In this study, we evaluated the use of cytocompatible methacryl-modified gelatin for the fabrication of a hydrogel-based tube by dip-coating and subsequent photo-initiated cross-linking. The wall thickness of the tubes and the diameter were tuned by the degree of gelatin methacryl-modification and the number of dipping cycles. The dipping temperature of the gelatin solution was adjusted to achieve low viscous fluids of approximately 0.1 Pa s and was different for gelatin derivatives with different modification degrees. A versatile perfusion bioreactor for the supply of surrounding tissue models was developed, which can be adaped to several geometries and sizes of blood-vessel mimicking tubes. The manufactured bendable gelatin tubes were permeable for water and dissolved substances, like Nile Blue and serum albumin. As a proof of concept, human fibroblasts in a three-dimensional collagen tissue model were sucessfully supplied with nutrients via the central gelatin tube under dynamic conditions for 2 days. Moreover, the tubes could be used as scaffolds to build-up a functional and viable endothelial layer. Hence, the presented tools can contribute to solving current challenges in tissue engineering.
Representing users within an immersive virtual environment is an essential functionality of a multi-person virtual reality system. Especially when communicative or collaborative tasks must be performed, there exist challenges about realistic embodying and integrating such avatar representations. A shared comprehension of local space and non-verbal communication (like gesture, posture or self-expressive cues) can support these tasks. In this paper, we introduce a novel approach to create realistic, video-texture based avatars of colocated users in real-time and integrate them in an immersive virtual environment. We show a straight forward and low-cost hard- and software solution to do so. We discuss technical design problems that arose during implementation and present a qualitative analysis on the usability of the concept from a user study, applying it to a training scenario in the automotive sector.
Workflow driven support systems in the peri-operative area have the potential to optimize clinical processes and to allow new situation-adaptive support systems. We started to develop a workflow management system supporting all involved actors in the operating theatre with the goal to synchronize the tasks of the different stakeholders by giving relevant information to the right team members. Using the OMG standards BPMN, CMMN and DMN gives us the opportunity to bring established methods from other industries into the medical field. The system shows each addressed actor their information in the right place at the right time to make sure every member can execute their task in time to ensure a smooth workflow. The system has the overall view of all tasks. Accordingly, a workflow management system including the Camunda BPM workflow engine to run the models, and a middleware to connect different systems to the workflow engine and some graphical user interfaces to show necessary information or to interact with the system are used. The complete pipeline is implemented with a RESTful web service. The system is designed to include different systems like hospital information system (HIS) via the RESTful web service very easily and without loss of data. The first prototype is implemented and will be expanded.
Three established test methods employed for evaluating the abrasion or wear resistance of textile materials were compared to gain deeper insight into the specific damaging mechanisms to better understand a possible comparability of the results of the different tests. The knowledge of these mechanisms is necessary for a systematic development of finishing agents improving the wear resistance of textiles. Martindale, Schopper, and Einlehner tests were used to analyze two different fabrics made of natural (cotton) or synthetic (polyethylene terephthalate) fibers, respectively. Samples were investigated by digital microscopy and scanning electron microscopy to visualize the damage. Damage symptoms are compared and discussed with respect to differences in the damaging mechanisms.
Abreinigbare Schlauchfilter kommen zur Abscheidung von Stäuben sowie staubförmigen Substanzen zum Einsatz. Aufgrund typischer Prozessbedingungen unterliegen sie während ihres Einsatzes thermischer, chemischer und mechanischer Beanspruchung. Das IGF-Projekt Nr. 18307 "Untersuchung der chemischen und thermischen Degradation von abreinigbaren Filtermedien und Verbesserung deren Beständigkeit durch Oberflächenmodifikation" hat mehrere Prüfmethoden verglichen.
The investigation of stress requires to distinguish between stress caused by physical activity and stress that is caused by psychosocial factors. The behaviour of the heart in response to stress and physical activity is very similar in case the set of monitored parameters is reduced to one. Currently, the differentiation remains difficult and methods which only use the heart rate are not able to differentiate between stress and physical activity, without using additional sensor data input. The approach focusses on methods which generate signals providing characteristics that are useful for detecting stress, physical activity, no activity and relaxation.
Aimed at the problem that the accuracy of face image classification in complex environment is not high, a network model F-Net suitable for aesthetic classification of face images is proposed. Based on LeNet-5, the model uses convolutional layers to extract facial image features in complex backgrounds, optimized parameters in the network model, and changes the number of convolutional layers and fully connected layer feature elements in the model. The experimental results show that the F-Net network model proposed in this paper has a face image classifation accuracy of 73% in complex environment background, which is better than other classical convolutional neural network classification models.
Age-dependent migratory behavior of human endothelial cells revealed by substrate microtopography
(2019)
Cell migration is part of many important in vivo biological processes and is influenced by chemical and physical factors such as substrate topography. Although the migratory behavior of different cell types on structured substrates has already been investigated, up to date it is largely unknown if specimen's age affects cell migration on structures. In this work, we investigated age-dependent migratory behavior of human endothelial cells from young (≤ 31 years old) and old (≥ 60 years old) donors on poly(dimethylsiloxane) microstructured substrates consisting of well-defined parallel grooves. We observed a decrease in cell migration velocity in all substrate conditions and in persistence length perpendicular to the grooves in cells from old donors. Nevertheless, in comparison to young cells, old cells exhibited a higher cell directionality along grooves of certain depths and a higher persistence time. We also found a systematic decrease of donor age dependent responses of cell protrusions in orientation, velocity and length, all of them decreased in old cells. These observations lead us to hypothesize a possible impairment of actin cytoskeleton network and affected actin polymerization and steering systems, caused by aging.
Digitalization changes the manufacturing dramatically. In regard of employees’ demands, global trends and the technological vision of future factories, automotive manufacturing faces a huge number of diverse challenges. Currently, research focuses on technological aspects of future factories in terms of digitalization. New ways of work and new organizational models for future factories have not been described yet. There are assumptions on how to develop the organization of work in a future factory but up to now, literature shows deficits in scientifically substantiated answers in this research area. Consequently, the objective of this paper is to present an approach on a work organization design for automotive Industry 4.0 manufacturing. Future requirements were analyzed and deducted to criteria that determine future agile organization design. These criteria were then transformed into functional mechanisms, which define the approach for shopfloor organization design
Die Faszination des "Touchpoint Airport" und der Trend hin zu immer mehr Mobilität machen Flughäfen für die werbungtreibende Wirtschaft zunehmend interessanter. Das belegen die Wachstumsraten der Out-of-Home-Werbung an Flughäfen und die Investitionen der Airports in analoge wie innovative digitale Medien. Der Grund dafür ist einfach: überdurchschnittlich kaufkräftige Zielgruppen lassen sich mit Flughafenwerbung über ihre gesamte Customer-Journey in einem besonderen Umfeld emotional ansprechen. Starken Brands bieten Airports die ideale Bühne für eine nachhaltige Markeninszenierung. Doch wie genau funktioniert Airport-Werbung, für welche Unternehmen eignet sich ein werblicher Auftritt am Flughafen, welche Zielgruppen lassen sich am Airport erreichen und wer sind die kompetenten Ansprechpartner für Airport-Werbung? Diese und viele weitere Fragen beantwortet das Jahrhuch Aiport Marketing 2020.
Angesichts großer globaler Herausforderungen wie z.B. dem Klimawandel befindet sich die Entwicklungszusammenarbeit im Wandel und sieht sich zunehmend der Frage ihrer Wirksamkeit gegenübergestellt. Dieser Beitrag diskutiert, welchen Beitrag Sustainable Entrepreneurship zu einer Verbesserung ihrer Wirksamkeit leisten kann. Im Rahmen dessen wird zunächst die Ethik Albert Schweitzers und ihre Bezüge zu Konzepten der Nachhaltigen Entwicklung beleuchtet und im nächsten Schritt kriteriengeleitet diskutiert, inwieweit Albert Schweitzer als Prototyp eines Sustainable Entrepreneurs bezeichnet werden kann und was dies für die Konzeption und Ausrichtung der Entwicklungszusammenarbeit bedeuten könnte. Ebenso wird diskutiert, inwieweit Nachhaltige Entwicklung, insb. die Nachhaltigkeitsziele der Vereinten Nationen (SDG) als Orientierungsrahmen für die Entwicklungszusammenarbeit dienen kann. Ausgehend von dem Befund, dass für Sustainable Entrepreneurs die Finanzierung ihrer Aktivitäten ein erheblicher Engpassfaktor darstellt, wird diskutiert, inwiefern Sustainable Finance-Instrumente dazu beitragen können, die Finanzierungsbedingungen für Sustainable Entrepreneurs und damit den Impact ihrer Aktivitäten zu verbessern. Abschließend wird anhand eines aktuellen Fallbeispiels der Impact aufgezeigt, den Sustainable Entrepreneurs, die nach dem Vorbild Albert Schweitzers agieren, erzielen können.
Interoperability is an important topic in the Internet of Things (IoT), because this domain incorporates diverse and heterogeneous objects, communication protocols and data formats. Many models and classification schemes have been proposed to make the degree of interoperability measurable - however only on the basis of a hierarchical scale. In the course of this paper we introduce a novel approach to measure the degree of interoperability using a metric scaled quantity. We consider IoT as a distributed system, where interoperable objects exchange messages with each other. Under this premise, we interpret messages as operation calls and formalize this view as a causal model. The analysis of this model enables us to quantify the interoperable behavior of communicating objects.
In Folge der gegenwärtigen Digitalisierung in der produzierenden Industrie werden Anwendungen oder Services mit potentiell positiven Auswirkungen auf Faktoren wie Effektivität und Arbeitsqualität entwickelt. Ein geeigneter Ansatz zur Stärkung motivierender Aspekte im Arbeitskontext kann Gamification darstellen. In dieser Arbeit ist die initiale Konzeption und Evaluation eines Gamification-Ansatzes für Anwender eines KI-Service zur Maschinenoptimierung dargestellt und möglichen Anforderungen an ein Konzept zur Motivationssteigerung extrahiert.
Die anwendungsneutrale und vorsorgliche Verkabelung gibt es bereits seit über 25 Jahren. Die Materie ist zunehmend komplexer geworden. Das ursprünglich für die informationstechnische Vernetzung von Büros vorgesehene Konzept hat sich mit den Jahren auf weitere Anwendungsbereiche, z. B. in Rechenzentren und in industriell oder privat genutzten Bereichen ausgeweitet. Dabei hat jeder Anwendungsbereich neben einem allgemeinen Anforderungsprofil auch ein eigenes, spezifisches Regelwerk. Aufgrund der fortschreitenden Digitalisierung ist zudem eine ständige technologische Anpassung und Weiterentwicklung des Leistungsvermögens vonnöten. Vor diesem Hintergrund wird es zunehmend schwierig, die umfangreichen Normenwerke zu lesen, im Zusammenspiel zu begreifen und optimal anzuwenden.
Und genau hier setzt das Buch an! In dem vorliegenden Buch wird die Kommunikationskabelanlage von der Idee über die Planung, die Spezifizierung, Realisierung, Inbetriebnahme bis hin zur Wartung anschaulich und im Zusammenhang erläutert. Kernstück ist die Vorstellung und Beschreibung der aktuellen Normenreihen DIN EN 50173 (VDE 0800-173) und DIN EN 50174 (VDE 0800-174). Nachdem zunächst auf die Standortvoraussetzungen eingegangen wird, folgen die allgemeinen und spezifischen Anforderungen an informationstechnische Verkabelungen und die verwendeten Komponenten, Kabel bzw. Steckverbinder und zu guter Letzt die Planung, Spezifizierung, Umsetzung und messtechnische Bewertung der Installation. Den Autoren ist es dabei ein Anliegen, nicht nur das Grundverständnis zu den relevanten Anforderungsprofilen zu vermitteln, sondern auch den Blick für den Gesamtzusammenhang, beispielsweise zur Zukunftssicherheit und zum Einfluss unterschiedlicher Umweltbedingungen auf die Auslegung der Verkabelungskomponenten, zu behalten.
The aim of this paper is to show to what extent Artificial Intelligence can be used to optimize forecasting capability in procurement as well as to compare AI with traditional statistic methods. At the same time this article presents the status quo of the research project ANIMATE. The project applies Artificial Intelligence to forecast customer orders in medium-sized companies.
Precise forecasts are essential for companies. For planning, decision making and controlling. Forecasts are applied, e.g. in the areas of supply chain, production or purchasing. Medium-sized companies have major challenges in using suitable methods to improve their forecasting ability.
Companies often use proven methods such as classical statistics as the ARIMA algorithm. However, simple statistics often fail while applied for complex non-linear predictions.
Initial results show that even a simple MLP ANN produces better results than traditional statistic methods. Furthermore, a baseline (Implicit Sales Expectation) of the company was used to compare the performance. This comparison also shows that the proposed AI method is superior.
Until the developed method becomes part of corporate practice, it must be further optimized. The model has difficulties with strong declines, for example due to holidays. The authors are certain that the model can be further improved. For example, through more advanced methods, such as a FilterNet, but also through more data, such as external data on holiday periods.
Due to Industry 4.0, the full value creation has the chance to undergo a fundamental technological transformation, the realisation of which, however, requires the commitment of every company for its own benefit. The new approaches of Industry 4.0 are often hardly evaluated, let alone proven, so that SMEs in particular often cannot properly estimate the potentials and risks, and often waiting too long with the migration towards Industry 4.0. In addition, they often do not pursue an integrated concept in order to identify possible potentials through changes in their business models. . As part of the research project "GEN-I 4.0 – Geschäftsmodell-Entwicklung für die Industrie 4.0” ", the ESB Business School at Reutlingen University of Applied Sciences and the Fraunhofer Institute for Industrial Engineering and Organization FHG IAO were engaged by the Baden-Württemberg Foundation from 2016 to 2018 to develop tools and an approach how the local economy can develop digital business models for itself in a methodical, beneficial and targeted manner. Through international analyses and interviews GEN-I 4.0 gained and concretized the knowledge required for the evaluation and selection of solutions and approaches for the transfer to develop digital business models. Together with the know-how of the project partners on Industry 4.0 and business model development, the findings were incorporated into the development of two software tools with which SMEs are shown the potentials of Industry 4.0 for their individual business model, online and in selfassessment, and given a comprehensive structured, concrete approach to development, as well as their individual risk. Users of the tools are supported by the selected platform for the networking of different players to implement innovative business models accompanied by coaching concepts for the companies in the follow-up and implementation of the assessment results.
It has not yet been possible to achieve the desired aim of decoupling economic growth from global material demand. Small and medium sized enterprises (SMEs) represent the backbone of most industrialized economies. Although material efficiency is of vital importance for many SMEs, few of them actually treat it as their top priority. There is a cornucopia of tools and methods available which can be used for material efficiency purposes. These, however, have gained little ground in the SME-field. This work deals with the enabling factors for material efficiency improvements in manufacturing SMEs and projections towards aspects of supply chain and circular economy. A multi-disciplinary decoupling approach for manufacturing SMEs and an implementation roadmap for further practical development are proposed. The approach combines appropriate complexity of technology and socio-economic considerations. It enables a connection of existing methods and the implementation of established information technologies.
Presently, many companies are transforming their strategy and product base, as well as their culture, processes and information systems to become more digital or to approach for a digital leadership. In the last years new business opportunities appeared using the potential of the Internet and related digital technologies, like Internet of Things, services computing, cloud computing, edge and fog computing, social networks, big data with analytics, mobile systems, collaboration networks, and cyber physical systems. Digitization fosters the development of IT environments with many rather small and distributed structures, like the Internet of Things, Microservices, or other micro-granular elements. This has a strong impact for architecting digital services and products. The change from a closed-world modeling perspective to more flexible open-world composition and evolution of micro-granular system architectures defines the moving context for adaptable systems. We are focusing on a continuous bottom-up integration of micro-granular architectures for a huge amount of dynamically growing systems and services, as part of a new digital enterprise architecture for service dominant digital products.
Artefaktkorrektur und verfeinerte Metriken für ein EEG-basiertes System zur Müdigkeitserkennung
(2019)
Fragestellung: Müdigkeit ist ein oft unterschätztes, aber dennoch großes Problem im Straßenverkehr. Von rund 2,5 Mio. Verkehrsunfällen 2015 in Deutschland, waren 2898 Unfälle, mit insgesamt 59 Toten (~1,7 % der Todesfälle), auf Übermüdung zurückzuführen. Schätzungen gehen von einer Dunkelziffer von bis zu 20 % aus. In einer ersten eigenen Studie wurde überprüft, ob ein mobiles EEG in einem Fahrsimulator Müdigkeitszustände zuverlässig erkennen kann. Die Erkennungsrate lag lediglich bei 61 %. Ziel dieser Arbeit ist, das verwendete Messsystem zu verbessern. Dazu wird die Genauigkeit durch eine Artefaktkorrektur und mit Hilfe von verfeinerten Qualitätsmetriken erhöht. Eine erkannte Übermüdung wird dem Fahrer dann in angemessener Weise angezeigt, so dass er entsprechend reagieren kann.
Patienten und Methoden: Die Independent Component Analysis (ICA) ist ein multivariates Verfahren, um mehrere Zufallsvariablen zu analysieren. Für die Entscheidung, ob ein Fahrer gerade müde oder wach ist, wird der erstellte Merkmalsvektor für jede Sequenz mit ICA klassifiziert. Dafür wird ein trainierter Machine-Learning-Algorithmus eingesetzt, der in der Lage ist, auch unbekannte Datensätze in Klassen einzuteilen. Um die benötigten Frequenzwerte zu erhalten, wurde für jeden EEG-Kanal eine Fourier Transformation durchgeführt. Der erstellte Merkmalsvektor wird im nächsten Schritt durch ein Künstliches Neuronales Netz klassifiziert. Für das Training werden vorab erstellte Merkmalsvektoren mit den Klassen „Wach“ und „Müde“ versehen. Diese Daten werden zufällig gemischt und im Verhältnis 2:1 in eine Trainings- und Testmenge geteilt. Das Experiment wurde mit acht Personen mit jeweils zweimal 45 min Testfahrt durchgeführt.
Ergebnisse: Der komplette Datensatz besteht aus 150.000 Signalwerten, welche zu ca. 7000 Sequenzen zusammengefasst werden. Durch die Anwendung der Qualitätsmetrik bleiben 4370 Sequenzen für das Training übrig. Bei invaliden Sequenzen aufgrund von EEG-Artefakten gibt es deutliche Unterschiede. Im „Wach“ Zustand werden dreimal so viele Sequenzen verworfen als im „Müde“ Zustand. Insgesamt werden bei wachen Probanden im Schnitt ca. 50 % der Sequenzen verworfen, bei Müden lediglich 25 %. Im Durchschnitt erreicht das System eine Erkennungsrate von 73 % für beide Zustände. Vergleicht man nun das Verhältnis von „Wach“ und „Müde“ und lässt „Leichte Müdigkeit“ außen vor, liegen die Ergebnisse bei über 90 %.
Schlussfolgerungen: Die Ergebnisse zeigen, dass die Aufmerksamkeit während des Experiments abnimmt bzw. die Müdigkeit zunimmt. Dies verdeutlichen zum einen subjektive und objektive Beobachtungen von Müdigkeitsanzeichen. Zum anderen lassen sich messbare und klassifizierbare Unterschiede im EEG Signal nachweisen. Die als Merkmale eingesetzten Theta-Wellen zeigten eine niedrigere Amplitude gegen Ende des Experiments. Die Erweiterung der binären Klassifizierung führt zu einer weiteren Stabilisierung der Ergebnisse. Artefaktkorrektur und Qualitätsmetriken steigern die Güte der Daten weiter. Die entwickelte Anwendung zur Müdigkeitserkennung ermittelt messbare Zeichen von Müdigkeit und kann eine gute Entscheidung über die Fahrtauglichkeit treffen.
Today many vertical retailers are operating different sales channels at the same time and are respon-sible for the range of products in all sales channels. The purpose of this paper is to examine whether for vertical fashion retailers a format-specific assortment policy can be observed on the German mar-ket. To investigate this topic in addition to secondary data of a literature research, quantitative prima-ry data was collected through a structured observation by conducting store checks. The combination provides insights into the research topic, allows to build hypotheses and to get a current and specific answer on the research topic. The study revealed all vertical retailers exploit the advantage of unlim-ited capacity of the online shop by offering in this channel mainly the broadest and deepest assort-ment. Within the retail store the vertical retailers focus on offering full-price goods for the current season in full size sets. Compared to the online shop here are less styles sophisticated presented and adjusted on the sales floor. For the outlet channel all brands showed a higher density of products and at least a price reduction of 30 per cent. The present paper is limited by time, depth and language of secondary data collection. As the study only conducted quantitative data within limited observations additional visual data over a longer period is necessary.
Purpose of the research paper is to illuminate the subject of assortment policy in the German fashion e‐commerce market. A short literature review is conducted in order to set up a system of characteristics to contemplate assortments on a strategic level. In a second step, structured observations are conducted to quantitatively analyze and compare the assortments of the leading online fashion retailers within Germany. Based on literature, the following characteristics for a classification of assortments can be identified: assortment structure, assortment size, assortment width, assortment depth, assortment consistency and rotation, price level, quality mix, fashion degree as well as the mix of private labels and manufacturer brands. Furthermore, the results of the empirical analysis show that there are currently five leaders within the nalyzed market: Amazon, Otto, Zalando, Baur and About You. Among these five market leaders, Amazon positions itself as a retailer that not only offers an enormous assortment size, but also the lowest entry prices as well as the broadest price dispersion. Through the development of the system of characteristics for assortment analysis and the examination of the current market environment, the findings of this paper contribute to the current state of the art in both theoretical and practical aspects.
While Microservices promise several beneficial characteristics for sustainable long-term software evolution, little empirical research covers what concrete activities industry applies for the evolvability assurance of Microservices and how technical debt is handled in such systems. Since insights into the current state of practice are very important for researchers, we performed a qualitative interview study to explore applied evolvability assurance processes, the usage of tools, metrics, and patterns, as well as participants’ reflections on the topic. In 17 semi-structured interviews, we discussed 14 different Microservice-based systems with software professionals from 10 companies and how the sustainable evolution of these systems was ensured. Interview transcripts were analyzed with a detailed coding system and the constant comparison method.
We found that especially systems for external customers relied on central governance for the assurance. Participants saw guidelines like architectural principles as important to ensure a base consistency for evolvability. Interviewees also valued manual activities like code review, even though automation and tool support was described as very important. Source code quality was the primary target for the usage of tools and metrics. Despite most reported issues being related to Architectural Technical Debt (ATD), our participants did not apply any architectural or service-oriented tools and metrics. While participants generally saw their Microservices as evolvable, service cutting and finding an appropriate service granularity with low coupling and high cohesion were reported as challenging. Future Microservices research in the areas of evolution and technical debt should take these findings and industry sentiments into account.
Based on a survey among customers of seven German municipal utilities, we estimate hierarchical multiple regression models to identify consumer motivations for participating in P2P electricity trading and develop implications for marketing strategies for this currently relatively unknown product. Our results show a low importance of socio-demographics in explaining differences between consumer groups, but high influence of attitudes, knowledge and likelihood to purchase related products. The most valuable target groups for P2P electricity trading marketing strategies of municipal utilities first and foremost should aim at are innovators, especially prosumers. They are well-informed about and open minded concerning electricity sharing and highly environmentally aware. They ask for transparency and are willing to purchase related products. They are attracted by the ability to share generation and consumption and to a lesser extent by economic reasons. Our results indicate that the marketing efforts should to a special degree take peer effects into account, as they are found to wield great influence on general openness towards and purchase intention for P2P electricity products. Finally, municipal utilities should build on the high level of satisfaction and trust of consumers and use P2P electricity trading as measure to keep and win customers willing to change their supplier.
Forschungsfrage: Wie können sich Unternehmen als attraktive Arbeitgeber positionieren, wenn sie bei jungen Bewerbern der Generation Y kaum bekannt sind und ihre Produkte als wenig attraktiv wahrgenommen werden?
Methodik: Szenariostudie mit Daten aus einer schriftlichen Befragung
Praktische Implikationen: Solche Unternehmen sollten auf die Nutzenversprechen einer Employer Brand setzen, um sich als attraktiver Arbeitgeber für diese Zielgruppe zu positionieren. Voraussetzung dafür ist eine auf die Zielgruppe abgestimmte und präzise Kommunikation über die relevanten Attraktivitätsmerkmale.
We report an investigation into the distribution of copper oxidation states in oxide films formed on the surfaces of technical copper. The oxide films were grown by thermal annealing at ambient conditions and studied using Auger depth profiling and UV–Vis spectroscopy. Both Auger and UV–Vis data were evaluated applying multivariate curve resolution (MCR). Both experimental techniques revealed that the growth of Cu2O dominates the initial ca. 40 nm of oxide films grown at 175 °C, while further oxide growth is dominated by CuO formation. The largely coincident results from both experimental approaches demonstrates the huge benefit of the application of UV–Vis spectroscopy in combination with MCR analysis, which provides access to information on chemical state distributions without the need for destructive sample analysis. Both approaches are discussed in detail.
Bei der spanenden Bearbeitung metallischer Werkstücke ist Verschleiß der Werkzeuge entscheidend für die Qualität der erzeugten Bauteiloberflächen und die Kosten der eingesetzten Werkzeuge. Damit ist der Werkzeugverschleiß und dessen Ursachen maßgebliches Auflegungskriterium für die Zerspanprozesse. Verschleiß wird dabei durch eine Vielzahl unterschiedlicher Parameter beeinflusst. Neben dem Werkstückwerkstoff, dem Schneidstoff und der Beschichtung sowie der Werkzeuggeometrie, sind die Schnittgeschwindigkeit, der Vorschub, die radiale und axiale Zustellung und die Prozessmedien ausschlaggebend für die Standzeit der Werkzeuge. Weitere Effekte gehen von den Eigenschaften des Werkstücks, Werkzeugs und der Maschinen aus. diese sind verantwortlich für die Entstehung von durch Instabilitäten verursachten Verschleiß. Im Folgenden wird die Systematik der Untersuchung unterschiedlich additivierter Kühlschmierstoffe auf den Verschleiß untersucht.
Anders als Digital-ICs, die hochautomatisiert entworfen werden können, ist der Entwurf analoger ICs bis heute Handarbeit. Übliche auf Optimierung basierende Automatisierungsverfahren scheitern. Die Ursachen wurden jetzt in einem Forschungsprojekt untersucht, um neue Ansätze zur Entwurfsautomatisierung analoger ICs abzuleiten.
Virtual Reality (VR) technology has the potential to support knowledge communication in several sectors. Still, when educators make use of immersive VR technology in favor of presenting their knowledge, their audience within the same room may not be able to see them anymore due to wearing head-mounted displays (HMDs). In this paper, we propose the Avatar2Avatar system and design, which augments the visual aspect during such a knowledge presentation. Avatar2Avatar enables users to see both a realistic representation of their respective counterpart and the virtual environment at the same time. We point out several design aspects of such a system and address design challenges and possibilities that arose during implementation. We specifically explore opportunities of a system design for integrating 2D video-avatars in existing roomscale VR setups. An additional user study indicates a positive impact concerning spatial presence when using Avatar2Avatar.
The present publication reports the purification effort of two natural bone blocks, that is, an allogeneic bone block (maxgraft®, botiss biomaterials GmbH, Zossen, Germany) and a xenogeneic block (SMARTBONE®, IBI S.A., Mezzovico Vira, Switzerland) in addition to previously published results based on histology. Furthermore, specialized scanning electron microscopy (SEM) and in vitro analyses (XTT, BrdU, LDH) for testing of the cytocompatibility based on ISO 10993-5/-12 have been conducted. The microscopic analyses showed that both bone blocks possess a trabecular structure with a lamellar subarrangement. In the case of the xenogeneic bone block, only minor remnants of collagenous structures were found, while in contrast high amounts of collagen were found associated with the allogeneic bone matrix. Furthermore, only island-like remnants of the polymer coating in case of the xenogeneic bone substitute seemed to be detectable. Finally, no remaining cells or cellular remnants were found in both bone blocks. The in vitro analyses showed that both bone blocks are biocompatible. Altogether, the purification level of both bone blocks seems to be favorable for bone tissue regeneration without the risk for inflammatory responses or graft rejection. Moreover, the analysis of the maxgraft® bone block showed that the underlying purification process allows for preserving not only the calcified bone matrix but also high amounts of the intertrabecular collagen matrix.
After the initiator of the ESB Logistics Learning Factory, Prof. Vera Hummel had made experience in developing and implementing a concept for a Learning Factory for Advanced Industrial Engineering (aIE) at the University of Stuttgart, Institute IFF between 2005 and 2008, she was appointed as a full professor at ESB Business School, a faculty of Reutlingen University in March 2010. Lacking a realistic, hands on learning and teaching environment of industrial scale for its industrial engineering students, first ideas for a Learning Factory that would strongly focus on all aspects of production logistics were drafted in 2012. Already back then, a strong integration of virtual and physical factory was desired: While the Learning Factory itself would be physical, the neighboring partners along the supply chain, such as suppliers or distribution warehouses, could be added in a fully virtual way. Considering implementation of the ESB Logistics Learning Factory a strategic initiative of the university, initial funding was provided by the faculty ESB Business School itself. Following its own creed, to provide future-oriented training for the region, also primarily local suppliers and manufacturers were selected as equipment providers to the new Learning Factory. During the initialization phase, 2014, a total of three researchers and nine students worked approximately four months to set up a first assembly line, storage racks, AGVs, or pick-by-light systems in conjunction with the underlying didactical concept. Since then, several hundred of students have participated in trainings and lectures held in the ESB Logistics Learning Factory, several research projects were carried out, and multiple high-level politicians and industry executives have been touring the shop floor. Also, more than EUR 2 million in research and infrastructure funds could be secured for expansion and upgrade — allowing the ESB Logistics Learning Factory today to represent many core aspects of an Industrie 4.0 production environment.
Kreativität, Problemlösekompetenz und kollaboratives Arbeiten werden in zahlreichen internationalen Studien sowie von der OECD (2017) als Schlüsselkompetenzen des 21. Jahrhunderts definiert. Ungeachtet dessen orientieren sich viele Lehr-Lern Methoden noch immer an der Vermittlung vordefinierter Lösungswege. Studien im Sekundarbereich in den USA, Deutschland und Asien zeigen, dass Design Thinking durch seine kreativen und kollaborativen Elemente zu einem nachhaltigeren Lernerfolg bei Lernenden und seitens der Lehrenden zu höherer Zufriedenheit bei der Vermittlung der Inhalte führen kann.
Kernelemente des Design Thinking sind: der iterative Prozess mit seinen Phasen Verstehen, Beobachten, Sichtweisen definieren, Ideen finden, Prototypen bauen, Testen; die Arbeit in multidisziplinären Teams sowie die Nutzerorientierung bei der Definition der Aufgabe (Brown, 2009). Die Phasen des iterativen Prozesses weisen eine hohe Kongruenz mit den prozessorientierten Kompetenzen des Faches Kunst/Werken und des Sachunterrichts gemäß dem Bildungsplan für Grundschulen (Ministerium für Kultus, Jugend und Sport Baden Württemberg, 2016) auf. Im Rahmen eines interdisziplinären Promotionsvorhabens an der PH Freiburg soll, basierend auf einem qualitativen Forschungsdesign, untersucht werden, inwieweit sich Design Thinking eignet, Kreativität, Problemlösekompetenz und kollaboratives Arbeiten von Grundschulkindern in Kunst/Werken und im Sachunterricht aus Sicht von Lehrpersonen zu fördern. Vorstudien mit Lehrpersonen und Ausbildungslehrkräften, bei welchen Erhebungen per Fragebogen nach Teilnahme an einem Design Thinking Workshop eingesetzt wurden, sowie zwei Pilotunterrichtseinheiten an Grundschulen mit Teilnehmender Beobachtung, Experteninterviews und Kinderinterviews in Kleingruppen, zeigen erste Ergebnisse.