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Das anhaltende Wachstum wissenschaftlicher Veröffentlichungen wirft die Fragestellung auf, wie Literaturana-lysen im Rahmen von Forschungsprozessen digitalisiert und somit produktiver realisiert werden können. Insbesondere in informationstechnischen Fachgebieten ist die Forschungspraxis durch ein rasant wachsendes Publikationsaufkommen gekennzeichnet. Infolgedessen bietet sich der Einsatz von Methoden der Textanalyse (Text Analytics) an, die Textdaten automatisch vorbereiten und verarbeiten können. Erkenntnisse entstehen dabei aus Analysen von Wortarten und Subgruppen, Korrelations- sowie Zeitreihenanalysen. Dieser Beitrag stellt die Konzeption und Realisierung eines Prototypen vor, mit dem Anwender bibliographische Daten aus der etablierten Literaturdatenbank EBSCO Discovery Service mithilfe textanalytischer Methoden erschließen können. Der Prototyp basiert auf dem Analysesystem IBM Watson Explorer, das Hochschulen lizenzkostenfrei zur Verfügung steht. Potenzielle Adressaten des Prototypen sind Forschungseinrichtungen, Beratungsunternehmen sowie Entscheidungsträger in Politik und Unternehmenspraxis.
Angesichts des anhaltenden Wachstums wissenschaftlicher Veröffentlichungen werden Instrumente benötigt, um Literaturanalysen durch Digitalisierung produktiver zu gestalten. Dieser Beitrag stellt einen Ansatz vor, der bibliographische Daten aus der Literaturdatenbank EBSCO Discovery Service mithilfe von Text-Analytics-Methoden erschließt. Die Lösung basiert auf dem Textanalysesystem IBM Watson Explorer und eignet sich für explorative Literaturanalysen, um beispielsweise den Status quo emergierender Technologiefelder in der Literatur zu reflektieren. Die generierten Ergebnisse sind in den Kontext der zunehmenden Werkzeugunterstützung des Literaturrechercheprozesses einzuordnen und können für intra- sowie interinstitutionelle Wissenstransferprozesse in Forschungs- und Beratungskontexten genutzt werden.
Im Rahmen der digitalen Transformation werden innovative Technologiekonzepte, wie z. B. das Internet der Dinge und Cloud Computing als Treiber für weitreichende Veränderungen von Organisationen und Geschäftsmodellen angesehen. In diesem Kontext ist Robotic Process Automation (RPA) ein neuartiger Ansatz zur Prozessautomatisierung, bei dem manuelle Tätigkeiten durch sogenannte Softwareroboter erlernt und automatisiert ausgeführt werden. Dabei emulieren Softwareroboter die Eingaben auf der bestehenden Präsentationsschicht, so dass keine Änderungen an vorhandenen Anwendungssystemen notwendig sind. Die innovative Idee ist die Transformation der bestehenden Prozessausführung von manuell zu digital, was RPA von traditionellen Ansätzen des Business Process Managements (BPM) unterscheidet, bei denen z. B. prozessgetriebene
Anpassungen auf Ebene der Geschäftslogik notwendig sind. Am Markt werden bereits unterschiedliche RPA-Lösungen als Softwareprodukte angeboten. Gerade bei operativen Prozessen mit sich wiederholenden Verarbeitungsschritten in unterschiedlichen Anwendungssystemen sind gute Ergebnisse durch RPA dokumentiert, wie z. B. die Automatisierung von 35 % der Backoffice-Prozesse bei Telefonica. Durch den vergleichsweise niedrigen Implementierungsaufwand verbunden mit einem hohen Automatisierungspotenzial ist in der Praxis (z. B. Banken, Telekommunikation, Energieversorgung) ein hohes Interesse an RPA vorhanden. Der Beitrag diskutiert RPA als innovativen Ansatz zur
Prozessdigitalisierung und gibt konkrete Handlungsempfehlungen für die Praxis. Dazu wird zwischen modellgetriebenen und selbstlernenden Ansätzen unterschieden. Anhand von generellen Architekturen von RPA-Systemen werden Anwendungsszenarien sowie deren Automatisierungspotenziale, aber auch Einschränkungen, diskutiert. Es folgt ein strukturierter Marktüberblick ausgewählter RPA-Produkte. Anhand von drei konkreten Anwendungsbeispielen wird die Nutzung von RPA in der Praxis verdeutlicht.
Nutzen und Rahmenbedingungen 5 informationsgetriebener Geschäftsmodelle des Internets der Dinge
(2018)
Im Kontext der zunehmenden Digitalisierung wird das Internet der Dinge (englisch: Internet of Things, IoT) als ein technologischer Treiber angesehen, durch den komplett neue Geschäftsmodelle im Zusammenspiel unterschiedlicher Akteure entstehen können. Identifizierte Schlüsselakteure sind unter anderem traditionelle Industrieunternehmen, Kommunen und Telekommunikationsunternehmen. Letztere sorgen mit der Bereitstellung von Konnektivität dafür, dass kleine Geräte mit winzigen Batterien nahezu überall und direkt an das Internet angebunden werden können. Es sind schon viele IoT-Anwendungsfälle auf dem Markt, die eine Vereinfachung für Endkunden darstellen, wie beispielsweise Philips Hue Tap. Neben Geschäftsmodellen basierend auf Konnektivität besteht ein großes Potenzial für informationsgetriebene Geschäftsmodelle, die bestehende Geschäftsmodelle unterstützen sowie weiterentwickeln können. Ein Beispiel dafür ist der IoT-Anwendungsfall Park and Joy der Deutschen Telekom AG, bei dem Parkplätze mithilfe von Sensoren vernetzt und Autofahrer in Echtzeit über verfügbare Parkplätze informiert werden. Informationsgetriebene Geschäftsmodelle können auf Daten aufsetzen, die in IoT-Anwendungsfällen erzeugt werden. Zum Beispiel kann ein Telekommunikationsunternehmen Mehrwert schöpfen, indem es aus Daten entscheidungsrelevantere Informationen – sogenannte Insights – ableitet, die zur Steigerung der Entscheidungsagilität genutzt werden. Außerdem können Insights monetarisiert werden. Die Monetarisierung von Insights kann nur nachhaltig stattfinden, wenn sorgfältig gehandelt wird und Rahmenbedingungen berücksichtigt werden. In diesem Kapitel wird das Konzept informationsgetriebener Geschäftsmodelle erläutert und anhand des konkreten Anwendungsfalls Park and Joy verdeutlicht. Darüber hinaus werden Nutzen, Risiken und Rahmenbedingungen diskutiert.
Prozessorientierte Messung der Customer Experience am Beispiel der Telekommunikationsindustrie
(2018)
Hohe Wettbewerbsintensität und gestiegene Kundenanforderungen erfordern bei Telekommunikationsunternehmen eine aktive Gestaltung der Customer Experience (CX). Ein wichtiger Aspekt dabei ist die CX-Messung. Traditionelle Zufriedenheitsmessungen sind oft nicht ausreichend, um die Kundenerfahrung in komplexen Prozessen vollständig zu erfassen. Daher wird in diesem Kapitel eine prozessübergreifende Referenzlösung zur CX-Messung am Beispiel der Telekommunikationsindustrie vorgeschlagen. Ausgangspunkt ist ein industriespezifisches Prozessmodell, das sich an dem Referenzmodell eTOM orientiert. Dieses wird um Messpunkte erweitert, die Schwachstellen in Bezug auf die CX identifizieren. Für die erkannten Schwachstellen werden über eine Referenzmatrix mögliche Auslöser abgeleitet und anhand von typischen Geschäftsfallmengen bewertet. Somit ist eine direkte Zuordnung und Erfolgsmessung konkreter Maßnahmen zur Behebung der Schwachstellen möglich. Die so entwickelte Referenzlösung wurde im Projekt K1 bei der Deutschen Telekom erfolgreich umgesetzt. Details zur Umsetzung werden als Fallstudien dargestellt.
Because of customer churn, strong competition, and operational inefficiencies, the telecommunications operator ME Telco (fictitious name due to confidentiality) launched a strategic transformation program that included a Business Process Management (BPM) project. Major problems were silo-oriented process management and missing cross-functional transparency. Process improvements were not consistently planned and aligned with corporate targets. Measurable inefficiencies were observed on an operational level, e.g., high lead times and reassignment rates of the incident management process.
Malaria infection remains a significant risk for much of the population of tropical and subtropical areas, particularly in developing countries. Therefore, it is of high importance to develop sensitive, accurate and inexpensive malaria diagnosis tests. Here, we present a novel aptamer-based electrochemical biosensor (aptasensor) for malaria detection by impedance spectroscopy, through the specific recognition between a highly discriminatory DNA aptamer and its target Plasmodium falciparum lactate dehydrogenase (PfLDH). Interestingly, due to the isoelectric point (pI) of PfLDH, the aptasensor response showed an adjustable detection range based on the different protein net-charge at variable pH environments. The specific aptamer recognition allows sensitive protein detection with an expanded detection range and a low detection limit, as well as a high specificity for PfLDH compared to analogous proteins. The specific feasibility of the aptasensor is further demonstrated by detection of the target PfLDH in human serum. Furthermore, the aptasensor can be easily regenerated and thus applied for multiple usages. The robustness, sensitivity, and reusability of the presented aptasensor make it a promising candidate for point-of-care diagnostic systems.
The chemical imaging sensor is a semiconductor-based chemical sensor capable of visualizing pH and ion distributions. The spatial resolution depends on the lateral diffusion of photocarriers generated by illumination of the semiconductor substrate. In this study, two types of optical setups, one based on a bundle of optical fibers and the other based on a binocular tube head, were developed to project a hybrid illumination of a modulated light beam and a ring-shaped constant illumination onto the sensor plate. An improved spatial resolution was realized by the ring-shaped constant illumination, which suppressed lateral diffusion of photocarriers by enhanced recombination due to the increased carrier concentration.
Synthetic mimics of natural high-performance structural materials have shown great and partly unforeseen opportunities for the design of multifunctional materials. For nacre-mimetic nanocomposites, it has remained extraordinarily challenging to make ductile materials with high stretchability at high fractions of reinforcements, which is however of crucial importance for flexible barrier materials. Here, highly ductile and tough nacre-mimetic nanocomposites are presented, by implementing weak, but many hydrogen bonds in a ternary nacre-mimetic system consisting of two polymers (poly(vinyl amine) and poly(vinyl alcohol)) and natural nanoclay (montmorillonite) to provide efficient energy dissipation and slippage at high nanoclay content (50 wt%). Tailored interactions enable exceptional combinations of ductility (close to 50% strain) and toughness (up to 27.5 MJ m⁻³). Extensive stress whitening, a clear sign of high internal dynamics at high internal cohesion, can be observed during mechanical deformation, and the materials can be folded like paper into origami planes without fracture. Overall, the new levels of ductility and toughness are unprecedented in highly reinforced bioinspired nanocomposites and are of critical importance to future applications, e.g., as barrier materials needed for encapsulation and as a printing substrate for flexible organic electronics.
False spectra formation in the differential two-channel scheme of the laser Doppler flowmeter
(2018)
Noise in the differential two-channel scheme of a classic laser Doppler flowmetry (LDF) instrument was studied. Formation of false spectral components in the output signal due to beating of electrical signals in the differential amplifier was found out. The improved block-diagram of the flowmeter was developed allowing to reduce the noise.
Monitoring of organic acids (OA) and volatile fatty acids (VFA) is crucial for the control of anaerobic digestion. In case of unstable process conditions, an accumulation of these intermediates occurs. In the present work, two different enzyme-based biosensor arrays are combined and presented for facile electrochemical determination of several process-relevant analytes. Each biosensor utilizes a platinum sensor chip (14 × 14 mm²) with five individual working electrodes. The OA biosensor enables simultaneous measurement of ethanol, formate, d- and l-lactate, based on a bi-enzymatic detection principle. The second VFA biosensor provides an amperometric platform for quantification of acetate and propionate, mediated by oxidation of hydrogen peroxide. The cross-sensitivity of both biosensors toward potential interferents, typically present in fermentation samples, was investigated. The potential for practical application in complex media was successfully demonstrated in spiked sludge samples collected from three different biogas plants. Thereby, the results obtained by both of the biosensors were in good agreement to the applied reference measurements by photometry and gas chromatography, respectively. The proposed hybrid biosensor system was also used for long-term monitoring of a lab-scale biogas reactor (0.01 m³) for a period of 2 months. In combination with typically monitored parameters, such as gas quality, pH and FOS/TAC (volatile organic acids/total anorganic carbonate), the amperometric measurements of OA and VFA concentration could enhance the understanding of ongoing fermentation processes.
Algal polysaccharides (extracellular polysaccharides) and carbon nanotubes (CNTs) were adsorbed on dioctadecyldimethylammonium bromide Langmuir monolayers to serve as a matrix for the incorporation of urease. The physicochemical properties of the supramolecular system as a monolayer at the air–water interface were investigated by surface pressure–area isotherms, surface potential–area isotherms, interfacial shear rheology, vibrational spectroscopy, and Brewster angle microscopy. The floating monolayers were transferred to hydrophilic solid supports, quartz, mica, or capacitive electrolyte–insulator–semiconductor (EIS) devices, through the Langmuir–Blodgett (LB) technique, forming mixed films, which were investigated by quartz crystal microbalance, fluorescence spectroscopy, and field emission gun scanning electron microscopy. The enzyme activity was studied with UV–vis spectroscopy, and the feasibility of the thin film as a urea sensor was essayed in an EIS sensor device. The presence of CNT in the enzyme–lipid LB film not only tuned the catalytic activity of urease but also helped to conserve its enzyme activity. Viability as a urease sensor was demonstrated with capacitance–voltage and constant capacitance measurements, exhibiting regular and distinctive output signals over all concentrations used in this work. These results are related to the synergism between the compounds on the active layer, leading to a surface morphology that allowed fast analyte diffusion owing to an adequate molecular accommodation, which also preserved the urease activity. This work demonstrates the feasibility of employing LB films composed of lipids, CNT, algal polysaccharides, and enzymes as EIS devices for biosensing applications.
Background
Impairment of neurovascular coupling (NVC) was recently reported in the context of subarachnoid hemorrhage and may correlate with disease severity and outcome. However, previous techniques to evaluate NVC required invasive procedures. Retinal vessels may represent an alternative option for non-invasive assessment of NVC.
Methods
A prototype of an adapted retinal vessel analyzer was used to assess retinal vessel diameter in mice. Dynamic vessel analysis (DVA) included an application of monochromatic flicker light impulses in predefined frequencies for evaluating NVC. All retinae were harvested after DVA and electroretinograms were performed.
Results
A total of 104 retinal scans were conducted in 21 male mice (90 scans). Quantitative arterial recordings were feasible only in a minority of animals, showing an emphasized reaction to flicker light impulses (8 mice; 14 scans). A characteristic venous response to flicker light, however, could observed in the majority of animals. Repeated measurements resulted in a significant decrease of baseline venous diameter (7 mice; 7 scans, p < 0.05). Ex-vivo electroretinograms, performed after in-vivo DVA, demonstrated a significant reduction of transretinal signaling in animals with repeated DVA (n = 6, p < 0.001).
Conclusions
To the best of our knowledge, this is the first non-invasive study assessing murine retinal vessel response to flicker light with characteristic changes in NVC. The imaging system can be used for basic research and enables the investigation of retinal vessel dimension and function in control mice and genetically modified animals.
For fuel flexibility enhancement hydrogen represents a possible alternative gas turbine fuel within future low emission power generation, in case of hydrogen production by the use of renewable energy sources such as wind energy or biomass. Kawasaki Heavy Industries, Ltd. (KHI) has research and development projects for future hydrogen society; production of hydrogen gas, refinement and liquefaction for transportation and storage, and utilization with gas turbine / gas engine for the generation of electricity. In the development of hydrogen gas turbines, a key technology is the stable and low NOx hydrogen combustion, especially Dry Low Emission (DLE) or Dry Low NOx (DLN) hydrogen combustion. Due to the large difference in the physical properties of hydrogen compared to other fuels such as natural gas, well established gas turbine combustion systems cannot be directly applied for DLE hydrogen combustion. Thus, the development of DLE hydrogen combustion technologies is an essential and challenging task for the future of hydrogen fueled gas turbines. The DLE Micro-Mix combustion principle for hydrogen fuel has been in development for many years to significantly reduce NOx emissions. This combustion principle is based on cross-flow mixing of air and gaseous hydrogen which reacts in multiple miniaturized “diffusion-type” flames. The major advantages of this combustion principle are the inherent safety against flashback and the low NOx-emissions due to a very short residence time of the reactants in the flame region of the micro-flames.
BACKGROUND
Immunosuppression is often considered as an indication for antibiotic prophylaxis to prevent surgical site infections (SSI) while performing skin surgery. However, the data on the risk of developing SSI after dermatologic surgery in immunosuppressed patients are limited.
PATIENTS AND METHODS
All patients of the Department of Dermatology and Allergology at the University Hospital of RWTH Aachen in Aachen, Germany, who underwent hospitalization for a dermatologic surgery between June 2016 and January 2017 (6 months), were followed up after surgery until completion of the wound healing process. The follow-up addressed the occurrence of SSI and the need for systemic antibiotics after the operative procedure. Immunocompromised patients were compared with immunocompetent patients. The investigation was conducted as a retrospective analysis of patient records.
RESULTS
The authors performed 284 dermatologic surgeries in 177 patients. Nineteen percent (54/284) of the skin surgery was performed on immunocompromised patients. The most common indications for surgical treatment were nonmelanoma skin cancer and malignant melanomas. Surgical site infections occurred in 6.7% (19/284) of the cases. In 95% (18/19), systemic antibiotic treatment was needed. Twenty-one percent of all SSI (4/19) were seen in immunosuppressed patients.
CONCLUSION
According to the authors' data, immunosuppression does not represent a significant risk factor for SSI after dermatologic surgery. However, larger prospective studies are needed to make specific recommendations on the use of antibiotic prophylaxis while performing skin surgery in these patients.
The available data on complications after dermatologic surgery have improved over the past years. Particularly, additional risk factors have been identified for surgical site infections (SSI). Purulent surgical sites, older age, involvement of head, neck, and acral regions, and also the involvement of less experienced surgeons have been reported to increase the risk of the SSI after dermatologic surgeries.1 In general, the incidence of SSI after skin surgery is considered to be low.1,2 However, antibiotics in dermatologic surgeries, especially in the perioperative setting, seem to be overused,3,4 particularly regarding developing antibiotic resistances and side effects.
Immunosuppression has been recommended to be taken into consideration as an additional indication for antibiotic prophylaxis to prevent SSI after skin surgery in special cases.5,6 However, these recommendations do not specify the exact dermatologic surgeries, and were not specifically developed for dermatologic surgery patients and treatments, but adopted from other surgical fields.6 According to the survey conducted on American College of Mohs Surgery members in 2012, 13% to 29% of the surgeons administered antibiotic prophylaxis to immunocompromised patients to prevent SSI while performing dermatologic surgery on noninfected skin,3 although this was not recommended by Journal of the American Academy of Dermatology Advisory Statement. Indeed, the data on the risk of developing SSI after dermatologic surgery in immunosuppressed patients are limited. However, it is possible that due to the insufficient evidence on the risk of SSI occurrence in this patient group, dermatologic surgeons tend to overuse perioperative antibiotic prophylaxis.
To make specific recommendations on the use of antibiotic prophylaxis in immunosuppressed patients in the field of skin surgery, more information about the incidence of SSI after dermatologic surgery in these patients is needed. The aim of this study was to fill this data gap by investigating whether there is an increased risk of SSI after skin surgery in immunocompromised patients compared with immunocompetent patients.
We present and discuss an exploration of the possibilities and properties of 3D printing with a printing space of 1 cubic meter, and how those can be integrated into architectural education through an experimental design and research course with students of architecture.We expand on issues presented at the eCAADe conference 2017 in Rome [Ref 6] by increasing the complexity and size of our prints, printing not a model to scale, but a full scale funtional prototype of a usable architectural object: A coffee bar.
Extrem hohe Blitzströme
(2018)
Blitze sind nach wie vor eine enorme Schadensquelle für Personenschäden, Brände, mechanische Zerstörungen und insbesondere auch Überspannungen. Das zeigen nicht zuletzt aktuelle Statistiken der Schadensversicherer. Immer wieder gibt es Meldungen über extrem hohe Blitzströme, die natürlich auch zu großen Schäden und Zerstörungen führen können. Dabei werden Scheitelwerte von teilweise deutlich über 300 kA genannt. Dies wirft Fragen auf, da die „klassische“ Blitzstatistik (z. B. nach CIGRE und IEC [8][10]) bisher solche Werte nicht kennt. Diese extremen Blitzströme werden meist aus den Daten von Blitzortungssystemen ermittelt.
Purpose — to compare the chemical elemental composition of vitreous cavity content taken from cadaveric eyes compared to samples taken from the eyes with terminal stage refractory glaucoma with decompensated intraocular pressure (IOP). Material and methods. The vitreous contents of the eyes from 2 groups were studied. The 1st group included 15 cadaveric eyes; the 2nd group included 15 eyes with refractory glaucoma in the terminal stage of the disease with decompensated IOP in patients with hypertension pain. The vitreal content samples were taken in the course of antiglaucoma surgery aimed at preserving the eye as an organ and involving employment of drainage in the vitreous cavity. The study of virtual contents was carried out on energy dispersive spectrometer Oxford X-Max 50 integrated into scanning electron microscope Zeiss EVO LS10. Results. Increased concentrations of Kalium and Phosphorus were detected in the vitreous content of cadaveric eyes compared with the vitreal content from the eyes with terminal glaucoma with decompensated IOP taken in vivo (K — 0.172/0.093; P — 0.045/0.025 mmol/L). In the vitreous cavity in the eyes with end-stage glaucoma with decompensated IOP, the concentration of Nitrogen was higher in comparison with human cadaver eyes (2.030/1.424 mmol/L). Conclusion. The increased concentrations of Kalium and Phosphorus in the vitreous content of cadaveric eyes is associated with postmortem autolytic processes and with the release of intracellular content in the destruction of cell membranes. The increased Nitrogen concentration in the vitreal contents of the eyes with terminal stage glaucoma with decompensated IOP may be associated with the presence of osmotically active nitrogen-containing compounds in the eyes with increased IOP.
Fahrzeugreifen
(2018)
Die Erfindung betrifft einen Fahrzeugreifen mit zumindest einem radial außen befindlichen Gummilaufstreifen, Wulstbereichen für den Anschluss an eine Felge und mit auf einer Gummimischung basierenden Seitenwandbereichen zwischen Gummilaufstreifen und den Wulstbereichen. Ferner betrifft die Erfindung Verfahren zur Herstellung solcher Fahrzeugreifen. Um den Anteil der umweltschädlichen Substanzen, insbesondere im Innenstadtbereich, zu reduzieren weisen die Seitenwandbereiche auf der äußeren Oberfläche eine für den oxidativen Abbau von Molekülen photokatalytisch aktive Substanz auf.
Manufacturing process simulation (MPS) has become more and more important for aviation and the automobile industry. A highly competitive market requires the use of high performance metals and composite materials in combination with reduced manufacturing cost and time as well as a minimization of the time to market for a new product. However, the use of such materials is expensive and requires sophisticated manufacturing processes. An experience based process and tooling design followed by a lengthy trial-and-error optimization is just not contemporary anymore. Instead, a tooling design process aided by simulation is used more often. This paper provides an overview of the capabilities of MPS in the fields of sheet metal forming and prepreg autoclave manufacturing of composite parts summarizing the resulting benefits for tooling design and manufacturing engineering. The simulation technology is explained briefly in order to show several simplification and optimization techniques for developing industrialized simulation approaches. Small case studies provide examples of an efficient application on an industrial scale.
Untersuchungen zur Tragfähigkeit und Steifigkeit eines neuartigen Wandelements in Holzbauweisen
(2018)
The Kremer-Grest (KG) bead-spring model is a near standard in Molecular Dynamic simulations of generic polymer properties. It owes its popularity to its computational efficiency, rather than its ability to represent specific polymer species and conditions. Here we investigate how to adapt the model to match the universal properties of a wide range of chemical polymers species. For this purpose we vary a single parameter originally introduced by Faller and Müller-Plathe, the chain stiffness. Examples include polystyrene, polyethylene, polypropylene, cis-polyisoprene, polydimethylsiloxane, polyethyleneoxide and styrene-butadiene rubber. We do this by matching the number of Kuhn segments per chain and the number of Kuhn segments per cubic Kuhn volume for the polymer species and for the Kremer-Grest model. We also derive mapping relations for converting KG model units back to physical units, in particular we obtain the entanglement time for the KG model as function of stiffness allowing for a time mapping. To test these relations, we generate large equilibrated well entangled polymer melts, and measure the entanglement moduli using a static primitive-path analysis of the entangled melt structure as well as by simulations of step-strain deformation of the model melts. The obtained moduli for our model polymer melts are in good agreement with the experimentally expected moduli.
Algorithmic design and resilience assessment of energy efficient high-rise water supply systems
(2018)
High-rise water supply systems provide water flow and suitable pressure in all levels of tall buildings. To design such state-of-the-art systems, the consideration of energy efficiency and the anticipation of component failures are mandatory. In this paper, we use Mixed-Integer Nonlinear Programming to compute an optimal placement of pipes and pumps, as well as an optimal control strategy.Moreover, we consider the resilience of the system to pump failures. A resilient system is able to fulfill a predefined minimum functionality even though components fail or are restricted in their normal usage. We present models to measure and optimize the resilience. To demonstrate our approach, we design and analyze an optimal resilient decentralized water supply system inspired by a real-life hotel building.
68Ga-radiopharmaceuticals are common in the field of Nuclear Medicine to visualize receptor-mediated processes. In contrast to straightforward labeling procedures for clinical applications, preclinical in vitro and in vivo applications are hampered for reasons like e.g. volume
restriction, activity concentration, molar activity and osmolality. Therefore, we developed a semiautomatic system specifically to overcome these problems. A difficulty appeared unexpectedly, as intrinsic trace metals derived from eluate (Zn, Fe and Cu) are concentrated as well in amounts that influence radiochemical yield and thus lower molar activity.
Often, research results from collaboration projects are not transferred into productive environments even though approaches are proven to work in demonstration prototypes. These demonstration prototypes are usually too fragile and error-prone to be transferred
easily into productive environments. A lot of additional work is required.
Inspired by the idea of an incremental delivery process, we introduce an architecture pattern, which combines the approach of Metrics Driven Research Collaboration with microservices for the ease of integration. It enables keeping track of project goals over the course of the collaboration while every party may focus on their expert skills: researchers may focus on complex algorithms,
practitioners may focus on their business goals.
Through the simplified integration (intermediate) research results can be introduced into a productive environment which enables
getting an early user feedback and allows for the early evaluation of different approaches. The practitioners’ business model benefits throughout the full project duration.
Das Forschungsprojekt Produktionseffizienz in der Kleinserie (ProeK) erarbeitet kostengünstige und effiziente Lösungsansätze für Prozessketten im Zukunftsfeld der Elektromobilität. Das Teilprojekt Karosserie setzt diese Zielsetzung durch innovative und praxisorientierte Produkt- und Prozesskonzepte mit neuartigen bauteilintegrierten Vorrichtungsfunktionen (BiV) um. Im Teilprojekt Außenhaut sollen Toleranzen adaptiv durch Anpassungen der Prozessparameter sowie Bauteilmanipulation kompensiert werden.
Comparison of different training algorithms for the leg extension training with an industrial robot
(2018)
In the past, different training scenarios have been developed and implemented on robotic research platforms, but no systematic analysis and comparison have been done so far. This paper deals with the comparison of an isokinematic (motion with constant velocity) and an isotonic (motion against constant weight) training algorithm. Both algorithms are designed for a robotic research platform consisting of a 3D force plate and a high payload industrial robot, which allows leg extension training with arbitrary six-dimensional motion trajectories. In the isokinematic as well as the isotonic training algorithm, individual paths are defined i n C artesian s pace by sufficient s upport p oses. I n t he i sotonic t raining s cenario, the trajectory is adapted to the measured force as the robot should only move along the trajectory as long as the force applied by the user exceeds a minimum threshold. In the isotonic training scenario however, the robot’s acceleration is a function of the force applied by the user. To validate these findings, a simulative experiment with a simple linear trajectory is performed. For this purpose, the same force path is applied in both training scenarios. The results illustrate that the algorithms differ in the force dependent trajectory adaption.
During rapid deceleration of the body, tendons buffer part of the elongation of the muscle-tendon unit (MTU), enabling safe energy dissipation via eccentric muscle contraction. Yet, the influence of changes in tendon stiffness within the physiological range upon these lengthening contractions is unknown. This study aimed to examine the effect of training-induced stiffening of the Achilles tendon on triceps surae muscle-tendon behavior during a landing task. Twenty-one male subjects were assigned to either a 10-week resistance-training program consisting of single-leg isometric plantarflexion (n = 11) or to a non-training control group (n = 10). Before and after the training period, plantarflexion force, peak Achilles tendon strain and stiffness were measured during isometric contractions, using a combination of dynamometry, ultrasound and kinematics data. Additionally, testing included a step-landing task, during which joint mechanics and lengths of gastrocnemius and soleus fascicles, Achilles tendon, and MTU were determined using synchronized ultrasound, kinematics and kinetics data collection. After training, plantarflexion strength and Achilles tendon stiffness increased (15 and 18%, respectively), and tendon strain during landing remained similar. Likewise, lengthening and negative work produced by the gastrocnemius MTU did not change detectably. However, in the training group, gastrocnemius fascicle length was offset (8%) to a longer length at touch down and, surprisingly, fascicle lengthening and velocity were reduced by 27 and 21%, respectively. These changes were not observed for soleus fascicles when accounting for variation in task execution between tests. These results indicate that a training-induced increase in tendon stiffness does not noticeably affect the buffering action of the tendon when the MTU is rapidly stretched. Reductions in gastrocnemius fascicle lengthening and lengthening velocity during landing occurred independently from tendon strain. Future studies are required to provide insight into the mechanisms underpinning these observations and their influence on energy dissipation.