Refine
Document Type
- Conference proceeding (1039) (remove)
Is part of the Bibliography
- yes (1039)
Institute
- Informatik (570)
- Technik (273)
- ESB Business School (163)
- Texoversum (24)
- Life Sciences (11)
- Zentrale Einrichtungen (2)
Publisher
- IEEE (222)
- Springer (145)
- Hochschule Reutlingen (112)
- Gesellschaft für Informatik e.V (57)
- Association for Computing Machinery (41)
- VDE Verlag (31)
- Association for Information Systems (30)
- SciTePress (21)
- IARIA (19)
- Elsevier (18)
Organizations identified the opportunities of big data analytics to support the business with problem-specific insights through the exploitation of generated data. Sociotechnical solutions are developed in big data projects to reach competitive advantage. Although these projects are aligned to specific business needs, common architectural challenges are not addressed in a comprehensive manner. Enterprise architecture management is a holistic approach to tackle complex business and IT architectures. The transformation of an organization’s EA is influenced by big data transformation processes and their data-driven approach on all layers. In this paper, we review big data literature to analyze which requirements for the EA management discipline are proposed. Based on a systematic literature identification, conceptual categories of requirements for EA management are elicited utilizing an inductive category formation. These conceptual categories of requirements constitute a category system that facilitates a new perspective on EA management and fosters the innovation-driven evolution of the EA management.
discipline.
An ongoing challenge in our days is to lower the impact on the quality of life caused by dysfunctionality through individual support. With the background of an aging society and continuous increases in costs for care, a holistic solution is needed. This solution must integrate individual needs and preferences, locally available possibilities, regional conditions, professional and informal caregivers and provide the flexibility to implement future requirements. The proposed model is a result of a common initiative to overcome the major obstacles and to center a solution on individual needs caused by dysfunctionality.
The increasing slew rate of modern power switches can increase the efficiency and reduce the size of power electronic applications. This requires a fast and robust signal transmission to the gate driver of the high-side switch. This work proposes a galvanically isolated capacitive signal transmission circuit to increase common mode transient immunity (CMTI). An additional signal path is introduced to significantly improve the transmission robustness for small duty cycles to assure a safe turn-off of the power switch. To limit the input voltage range at the comparator on the secondary side during fast high-side transitions, a clamping structure is implemented. A comparison between a conventional and the proposed signal transmission is performed using transistor level simulations. A propagation delay of about 2 ns over a wide range of voltage transients of up to 300V/ns at input voltages up to 600V is achieved.
In practice, the use of layout PCells for analog IC design has not advanced beyond primitive devices and simple modules. This paper introduces a Constraint-Administered PCell-Applying Blocklevel Layout Engine (CAPABLE) which permits PCells to access their context, thus enabling a true "bottom-up" development of complex parameterized modules. These modules are integrated into the design flow with design constraints and applied by an execution cockpit via an automatically built layout script. The practical purpose of CAPABLE is to easily generate full-custom block layouts for given schematic circuits. Perspectively, our results inspire a whole new conception of PCells that can not only act (on demand), but also react (to environmental changes) and interact (with each other).
Power loss measurement of power electronic components and overall systems is sometimes difficult by use of electrical quantities and in few applications even not possible. The calorimetric power loss measurement is an established method to identify the overall system losses with a suitable accuracy. This paper presents a novel method with an open chamber calorimeter under accurate air mass flow, air pressure, humidity measurement and temperature control. The benefits are the approximately halved measurement time compared to established systems and the possibility to control the chamber temperature. So it is possible to measure the power losses at different ambient temperatures.
Even though near-data processing (NDP) can provably reduce data transfers and increase performance, current NDP is solely utilized in read-only settings. Slow or tedious to implement synchronization and invalidation mechanisms between host and smart storage make NDP support for data-intensive update operations difficult. In this paper, we introduce a low-latency cache-coherent shared lock table for update NDP settings in disaggregated memory environments. It utilizes the novel CCIX interconnect technology and is integrated in neoDBMS, a near-data processing DBMS for smart storage. Our evaluation indicates end-to-end lock latencies of ∼80-100ns and robust performance under contention.
Continuous monitoring of individual vital parameters can provide information for the assessment of one’s health and indications of medical problems in the context of personalized medicine. Correlations between parameters and health issues are to be evaluated. As one project in this topic area, a telemedicine platform is implemented to gather data of outpatients via wearables and accumulate them for physicians and researchers to review. This work extracts requirements, draws use case scenarios, and shows the current system architecture consisting of a patient application, a physician application with a web server, and a backend server application. In further work, the prototype will assist to develop a vendor-free and open monitoring solution. A conclusion on functionality and usability will be evaluated in an imminent first study.
Non-fungible tokens (NFTs) are unique digital assets that have recently gained significant popularity, particularly in the digital art sector. The success of NFTs and other blockchain-based innovations depends on their ac-acceptance and use by consumers. This study aims to understand the impact of moral values on the acceptance of NFTs. Based on a quantitative survey with over 800 complete responses, the analysis shows that moral aspects of NFTs are indeed important for potential users. However, there is an attitude-behavior gap, as the positive impact of moral values on the intention to use NFTs is not reflected in the actual current usage of NFTs by the respondents. This study contributes to knowledge by providing new empirical data on the acceptance of NFTs and highlighting the role of moral values on the acceptance decision.
In 2013, Royal Philips was two years into a daunting transformation. Following declining financial performance, CEO Frans van Houten aimed to turn the Dutch icon into a "high-performing Company" by 2017. This case study examines the challenges of the business-driven IT transformation at Royal Philips, a diversified technology company. The case discusses three crucial issues. First, the case reflects on Philips’ aim at creating value from combining locally relevant products and services while also leveraging its global scale and scope. Rewarded and unrewarded business complexity is analyzed. Second, the case identifies the need to design and align multiple elements of an enterprise (organizational, cultural, technical) to balance local responsiveness with global scale. Third, the case explains the role of IT (as an asset instead of a liability) in Philips’ transformation and discusses the new IT landscape with its digital platforms, and the new practices to create effective business-IT partnerships.
The energy sector in Germany, as in many other countries, is undergoing a major transformation. To achieve the climate targets, numerous measures to implement smart energy and resource efficiency are necessary. Therefore, energy companies are experiencing increasing pressure from politics and society to transform their business areas in a sustainable manner and implement smart and sustainable business models. Consequently, numerous resources are expected to flow into the development and implementation of new business models. But often these efforts remain unsuccessful in practice. There is a large amount of literature on barriers and drivers of smart and sustainable business models in the energy sector. But what are the factors that companies struggle with most when developing and implementing new business models in practice? To answer this question, the results of a systematic literature review were evaluated by conducting semi-structured interviews with experts of the German energy sector. Six categories of transformation barriers were identified: Organizational, Financial, Legal, Partner-Network, Societal and Technological barriers. To overcome these barriers, recommendations for action and key success factors are outlined by the experts interviewed. The interview study validates key barriers and drivers in terms of their significance in practice in the German energy sector and makes recommendations to advance the smart and sustainable transformation of the energy sector.
In a time of upheaval and digitalization, new business models for companies play an important role. Decentralized power generation and energy efficiency indicators to achieve climate goals and to reduce global warming are currently forcing energy companies to develop new business models. In recent years, many methods of business model development have been introduced to create new business ideas. But what are the obstacles in implementing these business models in the energy sector to develop new business opportunities? And what challenges do companies face in this respect? To answer this question, a systematic literature review was conducted in this paper. As a result, eight categories were identified which summarise the main barriers for the implementation of new business models in the energy domain.
The energy turnaround, digitalization and decreasing revenues forces enterprises in the energy domain to develop new business models. Following a Design Science Research approach, we showed in two action research projects that businesses models in the energy domain result in complex ecosystems with multiple actors. Additionally, we identified that municipal utilities have problems with the systematic development of business models. In order to solve the problem, we captured together with the partners of the enterprises the requirements in a second phase. Further we developed a method which consist of the following components: Method for the creative development of a new business model in form of a Business Model Canvas (BMC). A mapping between the e3Value ontology and the BMC for modelling a business ecosystem. The Business Model Configurator (BMConfig) prototype for modelling and simulating the e3Value-Ontology. The Business model can be quantified and analyzed for its viability. We demonstrate the feasibility of our approach in business model of a power community.
This paper investigates the impact of dynamic capabilities (DC) on brand love. From a resource-based view, there is little clarity vis-à-vis the specific capabilities that drive the ability to create brand love. This paper focuses on three research questions: Firstly, which dynamic capabilities are relevant for brand love? Secondly, how strong is the impact of certain dynamic capabilities on brand love? Thirdly, which conditions mediate and moderate the impact of specific dynamic capabilities on brand love? Data from a multi-method research approach have been used to itentify the specific capabilities that corporations need, to enhance brand love. Furthermore, a standardized online survey was conducted on marketing executives and evaluated by structural equation modeling. The results indicate, that customer expertise plays a major role in the relationship between dynamic capabilities and brand love. Furthermore, this relationship is more important in markets that have a low competitive differentiation in products and services.
As "the most international company on earth", DHL Express promised to deliver packages between almost any pair of countries within a defined time-frame. To fulfill this promise, the company had introduced a set of global business and technology standards. While standardization had many advantages (improving service for multinational customers, faster response to changes in import/export regulations, sharing of best practices etc.), it created impediments to local innovation and responsiveness in DHL Express' network of 220 countries/territories. Reconciling standardization-innovation tradeoffs is a critical management issue for global companies in the digital economy.
This case describes one large, successful company's approach to the tradeoff of standardization versus innovation.
Enterprise Architecture (EA) management is an activity that seeks to foster the alignment of business and IT, and pursues various goals further operationalizing this alignment. Key to effective EA management is a framework that defines the roles, activities, and viewpoints used for EA management in accordance to the concerns that the stakeholders aim to address. Consensus holds that such frameworks are organization-specific and hence they are designed in governance activities for EA management. As of today, top-down approaches for governance are used to derive organization-specific frameworks. These usually lack systematic mechanisms for improving the framework based on the feedback of the responsible stakeholders. We outline a bottom-up approach for EA management governance that systematically observes the behavior of the actors to learn user concerns and recommend appropriate viewpoints. With this approach, we complement traditional top-down governance activities.
Bootstrap circuits are mainly used for supplying a gate driver circuit to provide the gate overdrive voltage for a high-side NMOS transistor. The required charge has to be provided by a bootstrap capacitor which is often too large for integration if an acceptable voltage dip at the capacitor has to be guaranteed. Three options of an area efficient bootstrap circuit for a high side driver with an output stage of two NMOS transistors are proposed. The key idea is that the main bootstrap capacitor is supported by a second bootstrap capacitor, which is charged to a higher voltage and connected when the gate driver turns on. A high voltage swing at the second capacitor leads to a high charge allocation. Both bootstrap capacitors require up to 70% less area compared to a conventional bootstrap circuit. This enables compact power management systems with fewer discrete components and smaller die size. A calculation guideline for optimum bootstrap capacitor sizing is given. The circuit was manufactured in a 180nm high-voltage BiCMOS technology as part of a high-voltage gate driver. Measurements confirm the benefit of high-voltage charge storing. The fully integrated bootstrap circuit including two stacked 75.8pF and 18.9pF capacitors results in a voltage dip lower than 1V. This matches well with the theory of the calculation guideline.
The main challenge when driving heat pumps by PV-electricity is balancing differing electrical and thermal demands. In this article, a heuristic method for optimal operation of a heat pump driven by a maximum share of PV-electricity is presented. For this purpose, the (DHW) are activated in order shift the operation of the heat pump to times of PV-generation. The system under consideration refers to thermal and electrical demands of a single family house. It consists of a heat pump, a thermal energy storage for DHW and of grid connected heating and generation of domestic hot water, the heat pump runs with two different supply temperatures and thereby achieving a maximum overall COP. Within the algorithm for optimization a set of heuristic rules is developed in a way that the operational characteristics of the heat pump in terms of minimum running and stopping times are met as well as the limiting constraints of upper and lower limits of room temperature and energy content of electricity generated, a varying number of heat pump schedules fulfilling the bundary conditions are created. Finally, the schedule offering the maximum on-site utilization of PV-electricity with a minimum number of starts of the heat pump, which serves as secondary condition, is selected. Yearly simulations of this combination have been carried out. Initial results of this method indicate a significant rise in on-site consumption of the PV-electricity and heating demand fulfilment by renewable electricity with no need for a massive TES for the heating system in terms of a big water tank.
Size and cost of a boost converter can be minimized by reducing the voltage overshoot and fastening the transient response in case of load transient. The presented technique improves the transient response of a current mode controlled boost converter, which usually suffers from bandwidth limitation because of its right-half-plane zero (RHPZ). The proposed technique comprises a load current estimation which works as part of a digital controller without any additional measurements. Based on the latest load estimation the controller parameters are adapted, achieving small voltage overshoot and fast transient response. The presented technique was implemented in a digital control circuit, consisting of an ASIC in a 110 nm-technology, a Xilinx Spartan-6 field programmable gate array (FPGA), and a TI-ADS8422 analog to-digital-converter (ADC). Simulation and measurements of a 4V-to-6.3V, 500mA boost converter show an improvement of 50% in voltage overshoot and response time to load transient.
Eine neue Methode zur Berechnung von Temperaturen in Bonddrähten umgeben von einem endlichen Mold wird vorgestellt. Sie ist schneller als die übliche Finite Elemente-Methode (FEM), während sie vergleichbare Resultate produziert. Für manche Parameter funktioniert unsere Methode, während die FEM-Methode versagt. Der Algorithmus ist im sogenannten Bondrechner implementiert, der eine leicht zu benutzende Oberfläche für Designer von mikroelektronischen Systemen bereitstellt. Seine Anwendung hat das Potential, die Zuverlässigkeit von Bonddrähten zu verbessern. Ein nichtidealer Parameter für den Wärmetransfer vom Bonddraht zum Mold-Package wurde ebenfalls berücksichtigt. Dieser Parameter ändert sich wahrscheinlich unter Alterseinflüssen und ist daher sehr wichtig für Zuverlässigkeits-Schätzungen. In unserer Methode wird die Wechselwirkung von Nachbardrähten ebenfalls berücksichtigt. Diese wird immer wichtiger, weil der Durchmesser und der wechselseitige Abstand der Bonddrähte sich verringert, wegen der fortschreitenden Miniaturisierung der Chip-Verpackungen. Unser Programm kann ebenfalls Temperaturen für transiente Ströme berechnen und den Strom berechnen, der zu einer gegebenen Maximaltemperatur gehört.
We introduce bloomRF as a unified method for approximate membership testing that supports both point- and range-queries. As a first core idea, bloomRF introduces novel prefix hashing to efficiently encode range information in the hash-code of the key itself. As a second key concept, bloomRF proposes novel piecewisemonotone hash-functions that preserve local order and support fast range-lookups with fewer memory accesses. bloomRF has near-optimal space complexity and constant query complexity. Although, bloomRF is designed for integer domains, it supports floating-points, and can serve as a multi-attribute filter. The evaluation in RocksDB and in a standalone library shows that it is more efficient and outperforms existing point-range-filters by up to 4× across a range of settings and distributions, while keeping the false-positive rate low.
Mit dem Betrieb von KWK-Anlagen lässt sich nennenswert Primärenergie einsparen. KWK-Anlagen werden aus diesem Grund aufgrund verschiedener Gesetze und Richtlinien gefördert. Zum wirtschaftlichen Betrieb einer KWK-Anlage ist es erforderlich, den größtmöglichen Teil des erzeugten elektrischen Stroms entweder selbst zu verbrauchen oder an Dritte (Mieter, Wohnungseigentümer…) zu verkaufen. Mit dem KWKG 2016 werden größere KWK-Anlagen interessant, und Anlagen mit geringerer jährlicher Laufzeit können sich sogar wirtschaftlicher darstellen als reine Grundlastanlagen.
This paper contributes to the automatic detection of perioperative workflow by developing a binary endoscope localization. Automated situation recognition in the context of an intelligent operating room requires the automatic conversion of low level cues into more abstract high level information. Imagery from a laparoscope delivers rich content that is easy to obtain but hard to process. We introduce a system which detects if the endoscope's distal tip is inside or outsiede the patient based on the endoscope video. This information can be used as one parameter in a situation recognition pipeline. Our localization performs in real-time at a video resolution of 1280x720 and 5-fold cross validation yields mean F1-scores of up to 0,94 on videos of 7 laparoscopies.
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.
Die Wirkungsgrade ("Normnutzungsgrade") nach DIN 4709 bilden den praktischen Betrieb von Mikro-Blockheizkraftwerken besser ab. Insbesondere bei den thermischen Wirkungsgraden ergeben sich nach DIN 4709 geringere Werte im Vergleich zu stationären Messungen aufgrund der An-/Abfahrverluste und der Speicherverluste. Der Betrieb des Zusatzkessels führt zu einer Reduktion der Primärenergieeinsparung der Gesamtanlage.
Job advertisements are important means of communicating role expectations for management accountants to the labor market. They provide information about which roles of management accountants are sought by companies or which roles are expected. However, which roles are communicated in job advertisements is unknown so far. Using a large sample of 889 job ads and a text-mining approach, we show an apparent mix of different role types with a strong focus on a rather classic role: the watchdog role. However, individuals with business partner characteristics are more often sought for leadership positions or in family businesses and small and medium-sized enterprises (SMEs). The results challenge the current role discussion for management accountants as business partners in practice and some academic fields.
In Zusammenarbeit mit dem Medizinproduktehersteller ulrich medical wird eine User Experience und Usability Studie an der Software der im Moment eingesetzten Kontrastmittelinjektoren durchgeführt. Das Unternehmen möchte eine neue Variante eines Kontrastmittelinjektors entwickeln, der als Basis eine verbesserte Version dieser Softwares enthält. Benutzerstudien können mit den unterschiedlichsten Methoden durchgeführt werden. Das geeignete Vorgehen muss definiert und die Testpersonen in Bezug zur eingesetzten Methode ermittelt werden. Bei Medizinprodukten muss zusätzlich auf strikte Auflagen in Normen und Gesetzen geachtet werden. Die Grundlage zur Methodenauswahl bildet eine Recherche zu Usability und User Experience Vorgaben für Medizinprodukte. Die Studie wird anhand quantitativer Daten eines Usability Tests im Labor, Fragebögen zur User Experience und qualitativen Post Test- Interviews evaluiert. In erster Linie dient diese Studie der Ermittlung von möglichen Verbesserungen, welche in der darauf folgenden Masterthesis vertieft und umgesetzt werden.
Excellence in IT is a key enabler for the digital transformation of enterprises. To realize the vision of digital enterprises it is necessary to cope with changing business requirements and to align business and IT. In order to evaluate the contribution of enterprise architecture management to these goals, our paper explores the impact of various factors to the perceived benefit of EAM in enterprises. Based on literature, we build an empirical research model. It is tested with empirical data of European EAM experts using a structural equation modelling approach. It is shown that changing business requirements, IT business alignment, the complexity of information technology infrastructure as well as enterprise architecture knowledge of information technology employees are crucial impact factors to the perceived benefit of EAM in enterprises.
Fundamentale Veränderungen der heutigen Arbeitswelt stellen Menschen, Systeme, Prozesse und ganze Organisationen vor erhebliche Herausforderungen. Der Faktor Mensch leistet in allen Bereichen dieses Wirkgefüges einen essentiellen Beitrag zum Wettbewerbsvorteil vieler produzierender Unternehmen am Standort Deutschland. Der Wandel von Automatisierung zu selbststeuernden Unternehmen geht dabei nicht spurlos an dem wandlungsfähigsten Glied dieses Gefüges, dem Menschen, vorüber. Belastungsarten verändern sich, singuläre Bewältigungsstrategien genügen nicht mehr, um einen optimalen Beanspruchungszustand jedes einzelnen Individuums zu erreichen und gleichzeitig das höchstmögliche Potenzial zu schöpfen. Das Belastungs- und Beanspruchungscockpit bildet einen Lösungsansatz zur systematischen und durchgängigen Bewertung von Belastungszuständen und der individuellen Beanspruchung von Beschäftigten an Montagearbeitsplätzen. Es liefert in Echtzeit Informationen zum Belastungs- und Beanspruchungszustand des Mitarbeiters und kann mit Ergonomiebewertungsverfahren verknüpft werden. Der Aspekt der Multidimensionalität umfasst die Bewertung verschiedener Indikatoren unter Betrachtung ihrer Wirkzusammenhänge.
Die bedarfsgerechte Steuerung dezentraler thermischer Energiesysteme, wie Kraft-Wärme-Kopplungs- (KWK-) Anlagen und Wärmepumpen, kann einen entscheidenden Beitrag zur Deckung bzw. Reduktion der Residuallast leisten und so für eine Verringerung der konventionellen Reststromversorgung und den damit einhergehenden Treibhausgasemissionen sorgen. Dafür wurde an der Hochschule Reutlingen in mehrjähriger Forschungsarbeit ein prognosebasierter Steuerungsalgorithmus entwickelt. Gegenstand dieses Beitrags bilden neben der Vorstellung eben jenes Steuerungsalgorithmus auch dessen praktische Umsetzungsvarianten: Eine auf einer speicherprogrammierbaren Steuerung (SPS) rein lokal ausführbare Version sowie eine Webservice-Anwendung für den parallelen Betrieb mehrerer Anlagen – ausgehend von einem zentralen Server. Erprobungen am KWK-Prüfstand der Hochschule Reutlingen bestätigen die zuverlässige Funktionsweise des Algorithmus in den verschiedenen Umsetzungsvarianten. Gleichzeitig wird der Vorteil der bedarfsgerechten Steuerung gegenüber dem, insbesondere im Mikro-KWK-Bereich standardmäßig vorliegenden, wärmegeführten Betrieb in Form einer Steigerung der Eigenstromdeckung von bis zu 27 % aufgezeigt. Neben der bedarfsgerechten Steuerung bedient der entwickelte Algorithmus zudem noch ein weiteres Anwendungsgebiet: Den vorhersagbaren KWK-Betrieb, der beispielsweise in Form täglicher Einspeiseprognose im Rahmen des Redispatch 2.0 eingefordert wird. Die Vorhersage des KWK-Betriebs ist dabei auf zwei Weisen möglich: Als erste Option kann der wärmegeführte Betrieb direkt über den Algorithmus abgebildet und prognostiziert werden. Eine andere Möglichkeit stellt wiederum die bedarfsgerechte Steuerung der Anlage dar; der berechnete optimale Fahrplan entspricht dabei gleichzeitig der Betriebsprognose des KWK-Geräts. Damit ist der entwickelte Steuerungsalgorithmus in der Lage, auf unterschiedliche Weisen zum Gelingen der Energiewende beizutragen.
It is assumed that more education leads to better understanding of complex systems. Some researchers claim, however, find indications that simple mechanisms like stocks and flows are not well understood even by people who have passed higher education. In this paper, we test people’s understanding of complex systems with the widely studied stock-and-flow (SF) tasks (Booth Sweeney and Sterman 2000). SF tasks assess people’s understanding of the interplay between stocks and flows. We investigate SF failure of domain experts and novices in different knowledge domains. In particular, we compare performance on the original study’s Bathtub task with the square wave pattern (Booth Sweeney and Sterman 2000) with two alternative cover stories from the engineering and business domains on different groups of business and engineering students from different semesters. Further, we show that, while engineering students perform better than business students, with progressing in higher education, students seem to lose the capability of dealing with simple SF tasks from domains other than their field. We thus find hints on déformation professionelle in higher education.
SF-failure, the inability of people to correctly determine the behavior of simple stock and flow structures is subject of a long research stream. Reasons for SF-failure can be attributed to different reasons, one of them being lacking domain specific experience, thus familiarity with the problem context. In this article we present a continuation of an experiment to examine the role of educational background in SF-performance. We base the question set on the Bathtub Dynamics tasks introduced by Booth Sweeney and Sterman (2000) and vary the cover stories. In this paper we describe how we developed and tested a new cover story for the engineering domain and implemented the recommendations from a prior study. We test three sets of questions with engineering students which enables us to compare the results to a previous study in which we tested the questions with business students. Results mainly support our hypothesis that context familiarity increases SF-performance. With our findings we further develop the methodology of the research on SF-failure.
Prior studies ascribed people’s poor performance in dealing with basic systems concepts to different causes. While results indicate that, among other things, domain specific experience and familiarity with the problem context play a role in this stock-flow-(SF-)performance, this has not yet been fully clarified. In this article, we present an experiment that examines the role of educational background in SF-performance. We hypothesize that SF-performance increases when the problem context is embedded in the problem solver’s knowledge domain, indicated by educational background. Using the square wave pattern and the sawtooth pattern tasks from the initial study by Booth Sweeney and Sterman (2000), we design two additional cover stories for the former, the Vehicle story from the engineering domain and the Application story from the business domain, next to the original Bathtub story. We then test the three sets of questions on business students. Results mainly support our hypothesis. Interestingly, participants even do better on a more complex behavioral pattern from their knowledge domain than on a simpler pattern from more distant domains. Although these findings have to be confirmed by further studies, they contribute both to the methodology of future surveys and the context familiarity discussion.
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 EU funded project RobLog recently developed a system able to autonomously unload coffee sacks from a standard container. Being the first of its kind, a further development is needed in order for the system to be competitive against manual labor. Financing this development entails a risk, hence a justified skepticism, which can be overcome by the longsighted view of the existing market potential. This paper presents a method to estimate the market potential of autonomous unloading systems for heavy deformable goods. Starting from the analysis of the coffee trade, first the current coffee traffic is investigated in order to calculate the number of autonomous systems needed to handle the imported sacks; Results are validated and the method is extended for the calculation of the potential of other market segments, where the same unloading technology can be applied.
Das Provisioning Tool automaIT wurde prototypisch um die Möglichkeit eines Data Discovery erweitert, mit dem Ziel, nicht durch automaIT verwaltete Systeme anbinden und steuern zu können. Daten aus dem Data Discovery werden mittels dem Tool Facter gesammelt und können dynamisch in ausführbare Modelle von automaIT integriert und ausgewertet werden. Dadurch kann der Verlauf weiterer Provisionierungsschritte gesteuert werden, ohne dass es eines manuellen Eingriffs bedarf.
According to several surveys and statistics, the great majority of companies previously not accustomed to automation are piloting solutions to automate business processes. Those accustomed to automation also attempt to introduce more of it, focusing on automation-unfriendly processes that remained manual. However, when the decision on what and whether to automate is not trivial for evident reasons, even industry leaders may get stuck on an overwhelming question: where to begin automating? The question remains too often unanswered as state-of-the-art methods fail to consider the whole picture. This paper introduces a holistic approach to the decision-making for investments in automation. The method supports the iterative analysis and evaluation of operative processes, providing tools for a quantitative approach to the decision-making. Thanks to the method, a large pool of processes can be first considered and then filtered out in order to select the one that yields the best value for the automation in the specific context. After introducing the method, a case study is reported for validation before the discussion.
The high system flexibility necessary for the full automation of complex and unstructured tasks leads to increased technological complexity, thus to higher costs and lower performance. In this paper, after an introduction to the different dimensions of flexibility, a method for flexible modular configuration and evaluation of systems of systems is introduced. The method starts from process requirements and, considering factors such as feasibility, development costs, market potential and effective impact on the current processes, enables the evaluation of a flexible systems of systems equipped with the needed functionalities before its actual development. This allows setting the focus on those aspects of flexibility that add market value to the system, thus promoting the efficient development of systems addressed to interested customers in intralogistics. An example of application of the method is given and discussed.
Physical analog IC design has not been automated to the same degree as digital IC design. This shortfall is primarily rooted in the analog IC design problem itself, which is considerably more complex even for small problem sizes. Significant progress has been made in analog automation in several R&D target areas in recent years. Constraint engineering and generator-based module approaches are among the innovations that have emerged. Our paper will first present a brief review of the state of the art of analog layout automation. We will then introduce active and open research areas and present two visions – a “continuous layout design flow” and a “bottom-up meets top-down design flow” – which could significantly push analog design automation towards its goal of analog synthesis.
In a time of digital transformation, the ability to quickly and efficiently adapt software systems to changed business requirements becomes more important than ever. Measuring the maintainability of software is therefore crucial for the long-term management of such products. With service-based systems (SBSs) being a very important form of enterprise software, we present a holistic overview of such metrics specifically designed for this type of system, since traditional metrics – e.g. object oriented ones – are not fully applicable in this case. The selected metric candidates from the literature review were mapped to 4 dominant design properties: size, complexity, coupling, and cohesion. Microservice-based systems (μSBSs) emerge as an agile and fine grained variant of SBSs. While the majority of identified metrics are also applicable to this specialization (with some limitations), the large number of services in combination with technological heterogeneity and decentralization of control significantly impacts automatic metric collection in such a system. Our research therefore suggests that specialized tool support is required to guarantee the practical applicability of the presented metrics to μSBSs.
DMOS transistors often suffer from substantial self-heating during high power dissipation, which can lead to thermal destruction if the device temperature reaches excessive values. A successfully demonstrated method to reduce the peak temperature is the redistribution of power dissipation density from the hotter to the cooler device areas by careful layout modification. However, this is very tedious and time-consuming if complex-shaped devices as often found in industrial applications are considered.
This paper presents an approach for fully automatic layout optimization which requires only a few hours processing time. The approach is applied to complex shaped test structures which are investigated by measurements and electro-thermal simulations. Results show a significantly lower peak temperature and an energy capability gain of 84 %, offering potential for a 18 % size reduction of active area.
Switched reluctance motors are particularly attractive due to their simple structure. The control of this machine type requires the instants, to switch the currents in the motor phases in an appropriate sequence. These switching instants are determined either based on a position sensor, or on signals generated by a sensorless method. A very simple sensorless method uses the switching frequency of the hysteresis controllers used for phase current control. This paper first presents an automatic commissioning method for this sensorless method and second a startup procedure, thus enhancing this approach towards an application in industry.
Automatic classification of rotating machinery defects using Machine Learning (ML) algorithms
(2020)
Electric machines and motors have been the subject of enormous development. New concepts in design and control allow expanding their applications in different fields. The vast amount of data have been collected almost in any domain of interest. They can be static; that is to say, they represent real-world processes at a fixed point of time. Vibration analysis and vibration monitoring, including how to detect and monitor anomalies in vibration data are widely used techniques for predictive maintenance in high-speed rotating machines. However, accurately identifying the presence of a bearing fault can be challenging in practice, especially when the failure is still at its incipient stage, and the signal-to-noise ratio of the monitored signal is small. The main objective of this work is to design a system that will analyze the vibration signals of a rotating machine, based on recorded data from sensors, in the time/frequency domain. As a consequence of such substantial interest, there has been a dramatic increase of interest in applying Machine Learning (ML) algorithms to this task. An ML system will be used to classify and detect abnormal behavior and recognize the different levels of machine operation modes. The proposed solution can be deployed as predictive maintenance for Industry 4.0.
The state of the art proposes the microservices architectural style to build applications. Additionally, container virtualization and container management systems evolved into the perfect fit for developing, deploying, and operating microservices in line with the DevOps paradigm. Container virtualization facilitates deployment by ensuring independence from the runtime environment. However, microservices store their configuration in the environment. Therefore, software developers have to wire their microservice implementation with technologies provided by the target runtime environment such as configuration stores and service registries. These technological dependencies counteract the portability benefit of using container virtualization. In this paper, we present AUTOGENIC - a model-based approach to assist software developers in building microservices as self configuring containers without being bound to operational technologies. We provide developers with a simple configuration model to specify configuration operations of containers and automatically generate a self-configuring microservice tailored for the targeted runtime environment. Our approach is supported by a method, which describes the steps to automate the generation of self-configuring microservices. Additionally, we present and evaluate a prototype, which leverages the emerging TOSCA standard.
Ein wirtschaftlicher Betrieb von KWK-Anlagen ist erreichbar, wenn Geräte mit gutem elektrischen Wirkungsgrad und geringen Anschaffungs- und Wartungskosten eingesetzt werden und der im BHKW erzeugte Strom zum größtmöglichen Anteil im Objekt verbraucht wird. Der Pufferspeicher einer KWK-Anlage sollte ausreichend groß bemessen sein (Flexibilität, Eigenstromoptimierung...). Ein größeres BHKW ist nicht automatisch unwirtschaftlicher aufgrund der geringeren Betriebszeit. Es bietet dagegen ein höheres Potenzial für eine bedarfsgerechte Stromeinspeisung in das Netz.
In mehreren Untersuchungen hat sich gezeigt, dass sich die Wahrnehmung des eigenen Körpers in einer virtuellen Umgebung positiv auf die Wahrnehmung der gesamten Umgebung auswirkt. Für diese Untersuchungen wurden der Körper einer Person, oder Teile davon, als animierter Avatar aus der Ego-Perspektive dargestellt. Im Kontext der Informatikkonferenz Informatics Inside 2014 an der Hochschule Reutlingen soll in dieser Arbeit eine andere Möglichkeit der Darstellung untersucht werden. In einer prototypischen Augmented Virtuality Anwendung soll die virtuelle Umgebung um reale Inhalte erweitert werden. Es soll einer Person ermöglicht werden, Teile ihres eigenen Körpers nicht als Avatar, sondern auf Basis einer Kameraaufnahme als realistische Repräsentation wahrzunehmen. Die Arbeit beschreibt hierbei die gesetzten Ziele, sowie Aufbau und Funktionsweise der prototypischen Anwendung und deren derzeitigen Stand.
Business Process Management (BPM) ist aufgrund seiner Bedeutung für prozessorientierte Unternehmen und den daraus resultierenden Anforderungen hinsichtlich interner Betriebsorganisation und Audits, ein zentraler Bestandteil. Die Einführung und Aufrechterhaltung von BPM stellt jedoch einen erheblichen Aufwand dar, da Prozesse aufgenommen, modelliert und aktuell gehalten werden müssen. Empirische Belege zeigen, dass erfolgreiche Prozessmodellierung dabei eine besondere Herausforderung darstellt, welche häufig nicht zufriedenstellend nachhaltig gelingt. Ein wesentlicher Erfolgsfaktor für die nachhaltige Prozessorientierung in Unternehmen ist somit die konsistente und aktuelle Prozessmodellierung, sowie deren Adaption an externe und interne Veränderungen. Mittels einer Literaturrecherche werden die relevanten Dimensionen zur nachhaltigen Prozessorientierung auf Grundlage der Prozessmodellierung ermittelt. Auf deren Basis wird ein adaptives handlungsorientiertes Framework für die praktische Anwendung in Unternehmen abgeleitet.
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.
Physicians in interventional radiology are exposed to high physical stress. To avoid negative long-term effects resulting from unergonomic working conditions, we demonstrated the feasibility of a system that gives feedback about unergonomic
situations arising during the intervention based on the Azure Kinect camera. The overall feasibility of the approach could be shown.
The promise of the EVs is twofold. First, rejuvenating a transport sector that still heavily depends on fossil fuels and second, integrating intermittent renewable energies into the power mix. However, it is still not clear how electricity networks will cope with the predicted increase in EVs and their charging demand, especially in combination with conventional energy demand. This paper proposes a methodology which allows to predict the impact of EV charging behavior on the electricity grid. Moreover, this model simulates the driving and charging behavior of heterogeneous EV drivers which differ in their mobility pattern, decision-making heuristics and charging strategies. The simulations show that uncoordinated charging results in charging load clustering. In contrast, decentralized coordination allows to fill the valleys of the conventional load curve and to integrate EVs without the need of a costly expansion of the electricity grid.