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Im folgenden Text möchte ich die verschiedenen Sterbehilfeformen etwas sortieren und einordnen. In der medialen Diskussion im Vorfeld der jüngst (ohne Ergebnis) erfolgten Bundestagsabstimmung zum § 217 StGB wurde die Schwierigkeit bei der Verwendung des Sterbehilfebegriffes besonders deutlich. Es war dabei oft nicht klar, ob es sich um die Beendigung von lebensverlängernden Maßnahmen, die Unterstützung beim Suizid oder die Tötung auf Verlangen handelt.
Despite the existence of societies, journals, conferences, and doctoral programs that generate increasing numbers of doctorates and research publications design research is not a coherent intellectual field with a clear boundary of its subject matter, nor an academic discipline founded on a consensual understanding of its purpose, methodology and pedagogical curriculum; subsequently, there is hardly any commonality across doctoral programs and the assessment of a doctoral degree is difficult if not impossible, so criticised the late design historian Victor Margolin. He called to unify and bound design research to solve these problems. While agreeing with his critiques and appreciating his good intentions, I will argue that his call is impractical as well as undesirable due to the social circumstances and the nature of design inquiry and the changing academic research practice which tend towards inter/transdisciplinarity. Efforts should rather be directed to join fragmented design research in an evolving and inclusive manner to establish a dynamically connected discipline.
In “Design Research: Making of a Connected Discipline Part 1”, I argue that the social circumstances and the nature of design inquiry and the changing academic research practice which tend towards inter/ trans-disciplinarity render building a unified and bounded discipline unrealistic and undesirable. In place of unified and bounded, I suggest connected to be a more viable concept to think about disciplinary
research in design. Here in Part 2, I make some suggestions to start making of a connected discipline.
Außerschulischen Bildungseinrichtungen, die ein Bildungsangebot für Menschen mit Behinderung realisieren wollen, stellt sich die Frage, welche Dinge es dabei zu beachten gilt. So setzte sich auch die Akademie Frankenwarte Würzburg im Rahmen des von der Bundeszentrale für politische Bildung geförderten Modellprojekts „Wer braucht denn Demokratie? Niedrigschwellige, aufsuchende politische Bildung für schwer erreichbare Zielgruppen entwickeln, durchführen und evaluieren“ mit der Planung und Durchführung einer Bildungsreise nach Strasbourg auseinander. In diesem Beitrag werden exemplarische Herausforderungen, die in diesem Prozess zu bewältigen waren, reflektiert.
„Politiker sind doch eh nicht unabhängig“ oder: Alltagshelden im Umgang mit Stammtischparolen
(2019)
Datenerfassung für die Anwendung lernender Algorithmen bei der Herstellung von Blechformteilen
(2020)
Der industrielle Fertigungsprozess von Blechformteilen unterliegt dem Einfluss einer Vielzahl von Parameterschwankungen, die das Umformergebnis signifikant mitbestimmen. Daher treten Qualitätsprobleme scheinbar zufällig auf und verursachen Ausschuss und einen Verlust an Produktivität. Ein vielversprechendes Mittel zur Verbesserung derartiger Prozesse ist der Einsatz von Datenanalysen und lernenden Algorithmen, die jedoch eine große Datenmenge voraussetzten. Bisher fehlten die Datenbasis und geeignete Möglichkeiten zur Datenerfassung für den Einsatz dieser Methoden.
In dieser Arbeit wurde eine allgemeingültige und übertragbare Methode zur Erfassung und Speicherung relevanter Einfluss- und Ergebnisgrößen des Herstellprozesses von Blechformteilen entwickelt. Die Methode und die resultierenden Daten sind die Grundlage für die Analyse von Zusammenhängen im Prozess, die Vorhersage der Qualität durch maschinelles Lernen und die Berechnung geeigneter Maschineneinstellungen. Diese Anwendungen wurden in der Arbeit erprobt und die Ergebnisse bewertet. Dadurch konnten die Funktionalität der Datenerfassung und die erwarteten Potentiale bestätigt werden.
Digital twins enable the digital representation of physical systems and provide comprehensive modelling and analysis capabilities. An online data exchange between the Digital twin and SAP is feasible, through integration of a transport control systems (SAP) via RESTful API. This interface allows decision making in resource allocation and furthermore the adaptation of the digital model if the real system changes. Despite the associated challenges in terms of data synchronisation, the integration has benefits such as a reduction in modelling effort and an increase in the lifetime of the digital twin. In the context of this work, the design of the interface between the simulation software and a SAP transport control system via RESTful API is described.
Current challenges in the planning and control of internal logistics systems are based on permanent changes in the requirements on the system, e.g., due to fluctuating order numbers or changes in their structure. For the representation and planning of in-house logistics processes, digital twins offer the possibility to verify different operational decisions such as predictive workforce scheduling. In this context, the quality of the results and their in-time presentation plays a decisive role. However, both target criteria are influenced by the detail-level of the digital representation. Based on a case study, this paper investigates the influence of the level of detail on the simulation runtime and result divergence to provide an evaluation for detail levels in the modelling of intralogistic transport systems.
In incremental spoken dialogue systems, par- tial hypotheses about what was said are re- quired even while the utterance is still ongo- ing. We define measures for evaluating the quality of incremental ASR components with respect to the relative correctness of the par- tial hypotheses compared to hypotheses that can optimize over the complete input, the tim- ingof hypothesisformationrelative to the por- tion ofthe inputthey areabout, andhypothesis stability, defined as the number of times they are revised. We show that simple incremen- tal post-processing can improve stability dra- matically, at the cost of timeliness (from 90% of edits of hypotheses being spurious down to 10% at a lag of 320ms). The measures are not independent,and we show how system de- signers can find a desired operating point for their ASR. To our knowledge, we are the first to suggest and examine a variety of measures for assessing incremental ASR and improve performance on this basis.
Incremental spoken dialogue systems, which process user input as it unfolds, pose additionalengineering challenges compared to more standard non-incremental systems: Their processingcomponents must be able to accept partial, and possibly subsequently revised input, and mustproduce output that is at the same time as accurate as possible and delivered with as little delay aspossible. In this article, we define metrics that measure how well a given processor meets thesechallenges, and we identify types of gold standards for evaluation. We exemplify these metrics inthe evaluation of several incremental processors that we have developed. We also present genericmeans to optimise some of the measures, if certain trade-offs are accepted. We believe that thiswork will help enable principled comparison of components for incremental dialogue systems andportability of results.
Die Nutzung virtueller Modelle zur Visualisierung historischer Gebäude stellt seit vielen Jahren einen Standard in der Vermittlung von Architekturgeschichte dar. Darüber hinaus besitzen diese Modelle ein großes Potenzial, um als Werkzeuge in Arbeitsprozessen von historischer Bauforschung und praktischer Denkmalpflege genutzt zu werden. Sie können beispielsweise dazu dienen, die Plausibilität von Rekonstruktionsvorschlägen frühzeitig im 3D-Raum zu überprüfen und mögliche Maßnahmen zwischen Wissenschaftler:innen, Politiker:innen, Bürger:innen und anderen Stakeholdern zu kommunizieren und diskutieren. In einem Workshop am Architekturreferat des DAI in Berlin wurde das virtuelle Modell des Basars von Aleppo als Fallstudie zu den genannten Fragen präsentiert.
Over the past decade, cars have turned gradually into real cyber physical systems. The collaboration of services between the service-oriented, cross-enterprise vehicle application frameworks has increased to generate novel, smart and complicated vehicle services. Consequently, from an interoperability perspective, semantically mapping of vehicle service component’s interface ontological models emerged as a big research interest in automotive application domain that manipulates several cross-enterprise synergy knowledge applications frameworks. The ontological metamodeling lays the foundation for building semantic bridge and exploring semantic associations between service components’ interface models based on the domain knowledge for semantic interoperability. Also, several semantic quality metrics has been defined over time for the vehicle service interface ontological metamodels. The empirically evaluated values of these metrics can be used to assess progress in cross-enterprise interoperability between the service and the clients’ APIs ontological models in vehicle domain. Despite potential benefits of semantic alignment quality metrics, the effective use of these metrics for vehicle service interface ontologies have proven elusive. Yes, such metrics can be used successfully for quantification, but then they mostly fail to provide adequate annotations in subsequent decision-making in the direction of semantic interoperability and reusability. The effective use of ontology semantic alignment quality metrics is basically hindered in the absence of the meaningful thresholds. In fact, the absence of an effective and meaningful threshold for the semantic similarity measure between various vehicle service interface ontological metamodels, motivates this research work which not only proposes a design approach to an optimized threshold for the semantic similarity metrics but also applies this threshold on few defined semantic alignment quality metrics. This paper also uses a real-world vehicle domain industrial case study to illustrate the design approach.
Additive Manufacturing (AM) is a future-oriented manufacturing technology that is experiencing an enormous boom in the times of Industry 4.0. As a result, various AM technologies and printer models from different manufacturers are entering the market over a short time span. With the advancing establishment of this manufacturing technology for series applications, the expectations and requirements of the fabricated components are also increasing. However, a major challenge is the application-specific selection of the most suitable AM process due to a lack of comparable data. Furthermore, there needs to be more know-how regarding the geometrical and mechanical characteristics of AM parts. This paper addresses this problem by comparing the three most common plasticbased AM processes in the areas of surface quality, dimensional accuracy, and mechanical properties. Roughness measurements, evaluation of a benchmark artifact, tensile tests, and load increase tests are carried out. Based on the results, the individual possibilities and limitations of the compared AM processes can be detected.
Menschen mit einer erworbenen Sprachstörung, Aphasie, erleben aufgrund ihrer Kommunikationseinschränkungen und der damit einhergehenden reduzierten Teilhabe eine verminderte Lebensqualität. Aphasie-Selbsthilfegruppen können Inklusion und Selbstwerterleben der Betroffenen besonders dann fördern, wenn sie von betroffenen Personen selbst geleitet werden. In dem hier vorgestellten Forschungsprojekt Selbsthilfegruppenarbeit bei Aphasie zur Steigerung der Lebensqualität und Kompetenz (shalk) wurde untersucht, wie von Aphasie betroffene Menschen auf die Übernahme einer Gruppenleitung vorbereitet und bei der Umsetzung begleitet werden können, um die Lebensqualität der betroffenen Leitungspersonen und auch der Gruppenteilnehmenden zu steigern.
Due to the complexity and the number of factors involved in factory layout planning, computers were identified as an efficient tool to support the process. However, so far no method for computer-aided layout planning has gained wide acceptance in practical application. One reason for this is that in present approaches either the user or the computer designs the layout, neglecting either the qualitative or the quantitative goals. To bridge this gap, this article introduces a concept for human-computer-integration based on evaluative feedback and inverse reinforcement learning. A key element of the concept is the interactive planning process in which user and computer alternately design and improve the layout until a satisfactory layout is found. The user evaluates the layouts according to qualitative criteria, adjusts them intuitively and specifies objectives and restrictions in an explorative way. The computer on the other hand – in form of a reinforcement algorithm – generates possible layouts and incorporates the user’s feedback into its policy. This synergy is expected to generate better results than an expert or an algorithm alone could. Furthermore, in the context of learning factories, it encourages critical thinking and allows students to develop a deeper understanding of the factors that contribute to efficient manufacturing processes. Both an architecture for the implementation is proposed and the requirements for the user interface are specified.
This paper briefly presents the challenges for order control and release of multi-zone order picking systems. On the one hand, the order control must ensure that all orders are processed on time, and on the other hand, the space requirements (buffer) and the utilisation of the zones must be considered.
Within the framework of a case study, different strategies for order release were developed. The paper shortly describes the ideas of the strategies and presents results of a case-based simulative evaluation of the strategies. The findings of the simulation study are the basis for the development of a digital twin for the operational control of multi-zone picking systems.
By simultaneous laser beam melting (SLBM), parts consisting of different polymer powders can be additively manufactured within one building process. Besides the advantages of conventional LBM, e.g., not needing additional tools and being able to realize parts with almost any geometry, different product requirements can be achieved within a single part. Product requirements may be different chemical resistances or haptic material properties. Therefore, SLBM enlarges the application field for additive manufacturing in general. In the process, two different materials are deposited on the building platform and preheated a few degrees below the melting temperature of the lower melting polymer by infrared emitters. Afterward, a CO2 laser (λ = 10.6 μm) provides the energy for the temperature difference between the preheating temperatures of both materials. Finally, a digital light processing chip is used to achieve simultaneous and flexible energy deposition for melting both preheated polymers. By illuminating the chip with a laser, parts of the beam can be flexibly guided onto the powder bed or into a beam trap. As laser, a single mode thulium laser (λ = 1.94 μm) is used. After melting the layer, a new layer is deposited and the process starts anew. In this paper, polypropylene and polyamide 12 are used as materials. After analyzing the material and melting behavior during the process by a high-resolution thermal imaging system, the parts are qualified regarding their material compatibility at the boundary zone and porosity by cross sections.
Zum Einsatz sportpsychologischen Trainings bzw. dem Kenntnisstand über diesbezügliche Maßnahmen im Fußball liegen noch keine Studien vor. Ziel der vorliegenden Studie war es daher, den Kenntnisstand und die tatsächliche Anwendung sportpsychologischer Maßnahmen bei Fußballtrainern verschiedener Lizenzstufen zu untersuchen. Als zentrales Ergebnis lässt sich konstatieren, dass dem sportpsychologischen Training von fast allen Trainern eine große Bedeutung zugesprochen wird, der Kenntnisstand jedochäußerst lückenhaft ist und der Einsatz entsprechender Intervention kaum stattfindet.
In the real-time systems sector, various task models and corresponding tests exist to model and verify the schedulability of task sets on the system at hand. While those models and schedulability tests have intensively been studied from a theoretical point of view, it is hard to ma e use of them to compare the actual execution behavior of scheduling algorithms on a real system. In contrast to schedulability tests, simulators can help to investigate the performance of specific scheduling algorithms. One of the most generalized task models to describe parallel tasks is the Directed Acyclic Graph model that allows to represent tasks as a series of subtasks that depict the potentially parallel computations and precedence constraints that denote the order in which the subtasks are allowed to execute.
In this paper, we investigate various scheduling algorithms for the Directed Acyclic Graph model. For that, we first recapitulate the examined scheduling algorithms in detail and point out relevant differences. Subsequently, we present the evaluation of different global and federated scheduling algorithms using fine-grained parallel tasks. To this end, we generate random Directed Acyclic Graph tasks and simulate their execution on multiprocessor systems using scheduling algorithms such as global rate-monotonic and semi-federated scheduling as well as global scheduling policies using the thread pool model.
Positionspapier (Einführung)
(2015)
Efficient earthquake simulation of stiff and high DOF bridge expansion joint models with Python
(2021)
Various types of seismic protection devices has been developed to protect structures like bridges from collapse during an earthquake event, such as hydraulic or metallic hysteresis dampers and spherical pendulum bearings. The expansion joints however, which are already included in most large-span bridges, are not considered as an
earthquake protection device regardless of the significant friction forces they produce. These friction forces can be seen as damping forces between the shaking environment and the oscillating bridge. To investigate the effect of those damping forces during different earthquake loads, a multibody dynamics simulation model of the expansion joints will be created. This model should be accurate enough to represent the generation of the damping forces and effects of the geometric setup of the expansion joints. Because large expansion joints for large-span bridges are of special interest, the number of degrees of freedom (DOF) becomes very high. Because this models include stiff bushings, implicit solvers need to be used to gain a stable simulation. Expansion joints are almost unique constructions for every specific bridge, which requires a automated model generation. Because of its excellent modules for numerical mathematics, the scripting language Python is used. To create an efficient simulation model, several optimization techniques such as Just-In-Time (JIT) compilation and parallelization are implemented and tested.
Im Rahmen des FFG-Forschungsprojektes „Entwicklung neuer dauerhafter und nachhaltiger Spritzbetone (Advanced and sustainable sprayed concrete; ASSpC)“ werden Methoden zur Prüfung der Calcium-Auslaugung von Spritzbeton eingesetzt bzw. weiterentwickelt. Bestimmt wurde dafür das Reduzierte Versinterungspotential nach Regelwerken der Österreichischen Bautechnik Vereinigung und das Auslaugverhalten von Spritzbeton bei leichtem Säureangriff (Salpetersäure und Kohlensäure), um dauerhaftigkeitsrelevante Parameter im Bereich der Wechselwirkungen von Spritzbeton mit leicht sauren (Kohlensäure- und Nitrathaltigen) Oberflächen-, Grund- und Sickerwässern zu untersuchen und potentielle Schädigungsmechanismen zu identifizieren und zu quantifizieren. Die Vor- und Nachteile der verwendeten Prüfmethoden zum lösenden Angriff werden in Bezug auf die Dauerhaftigkeit von Spritzbeton diskutiert.
Different higher education backgrounds in China and Germany led to challenges in the curriculum design at the beginning of our cooperative bachelor program in Optoelectronics Engineering. We see challenges in different subject requirements from both sides and in the German language requirements for Chinese students. The curriculum was optimized according to the AS IIN criteria, which makes it acceptable and und erstandable by both countries. German students are integrated into the Chinese class and get the sa me lectures like their Chinese colleagues. Intercultural and curriculum challenges are successfully solved. The results are summarized to provide an example for other similar international programs.
Codes of practice aim to assure structures have acceptable risks to the public and the minimum total costs over the working life of a design. However, current codified criteria for structural design correspond to a broad range of reliability levels, specified for dissimilar reference periods even though their recalculation for different periods is uncertain due to unknown dependence of failure events in time. In this contribution, target reliability levels are specified on the basis of probabilistic risk optimization considering the objective function as a sum of various costs including effects of time to failure and discounting. A case study presents probabilistic optimization of the roof of a stadium for 4,000 spectators and illustrates the effect of the considered input parameters. Failure consequences and relative cost of safety measure are shown to be major factors affecting the optimum reliability level. Less important factors are the discount rate and working life. Large uncertainty in failure cost estimates seems to have only a marginal effect on derived optimum reliability levels.
Tissue-engineered vessel grafts have to mimic the biomechanical properties of native blood vessels. Manufacturing processes often condition grafts to adapt them to the target flow conditions. Graft stiffness is influenced by material properties and dimensions and determines graft compliance. This proof-of-concept study evaluated a contact-free method to monitor biomechanical properties without compromising sterility. Forced vibration response analysis was performed on human umbilical vein (HUV) segments mounted in a buffer-filled tubing system. A linear motor and a dynamic signal analyser were used to excite the fluid by white noise (0-200 Hz). Vein responses were read out by laser triangulation and analysed by fast Fourier transformation. Modal analysis was performed by monitoring multiple positions of the vessel surface. As an inverse model of graft stiffening during conditioning, HUV were digested proteolytically, and the course of natural frequencies (NFs) was monitored over 120 min. Human umbilical vein showed up to five modes with NFs in the range of 5-100 Hz. The first natural frequencies of HUV did not alter over time while incubated in buffer (p = 0.555), whereas both collagenase (-35%, p = 0.0061) and elastase (-45%, p < 0.001) treatments caused significant decreases of NF within 120 min. Decellularized HUV showed similar results, indicating that changes of the extracellular matrix were responsible for the observed shift in NF. Performing vibration response analysis on vessel grafts is feasible without compromising sterility or integrity of the samples. This technique allows direct measurement of stiffness as an important biomechanical property, obviating the need to monitor surrogate parameters. Copyright (C) 2016 John Wiley & Sons, Ltd.
Risk and reliability criteria are well established in many industrial sectors such as the offshore, chemi- cal or nuclear industries. Comparative risk thresholds have been specified to allow a responsible organization or regulator to identify activities, which impose an acceptable level of risk concerning the participating individuals, or society as a whole. The scope of this contribution is to present target reliability criteria based on acceptable human safety levels. Application of theoretical principles is illustrated by examples of railway engineering structures. Initially it is shown how civil engineering structures for which human safety criteria play a role are classified according to Eurocodes. Examples include bridges, tunnels or station buildings. The general concepts for risk acceptance are then briefly reviewed, particularly in their relation to the target reliability criteria. The distinction between the two types of criteria is made: group risk and the acceptance criterion based on the Life Quality Index LQI approach introduced by ISO 2394:2015. The differences between the criteria for new and existing structures are discussed. The application is illustrated by an example of a bridge crossing an important railway line. It appears that while benefits and costs of a private stakeholder or public authority are reflected by economic optimisation, the society should define the limits for human safety to achieve uniform risks for various daily-life activities and across different industrial sectors. Keywords: group risk, human safety, individual risk, Life Quality Index, railway, risk acceptance, structure, target reliability