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Hintergrund Die physiotherapeutische Dokumentation spielt im Therapieprozess eine wichtige Rolle, erfolgt jedoch auf unterschiedlichste Weise. Es existieren derzeit eine Vielzahl von Softwarelösungen für die physiotherapeutische Dokumentation, welche sich jedoch in ihren Funktionalitäten stark unterscheiden. Ziel Mithilfe einer Befragung soll ein Konsens von Expertenaus der Physiotherapie im Themengebiet der softwarebasierten Dokumentation ermittelt werden. Anhand der Ergebnisse wird ein Anforderungskatalog für die Entwicklung einer neuartigen und benutzerorientierten Dokumentationssoftware erstellt. Methode Online-Delphi-Befragung mit neun Experten über drei Befragungswellen.
Ergebnisse Hinsichtlich der Anforderungen an die Anamnese konnte ein Konsens erzielt werden. Bei der Gliederung des Befundes kam es zu keiner Übereinstimmung der Experten. Das Ergebnis lässt sich durch unterschiedliche manualtherapeutische Konzepte erklären, die für die Befunderhebung verwendet wurden. Schlussfolgerung Eine softwarebasierte Dokumentation sollte standardisierter als bisher erfolgen, um den ClinicalReasoning-Prozess zu unterstützten. Gleichzeitig ist dabei eine gewisse Flexibilität geboten. Die gesammelten Anforderungen können für die Entwicklung einer neuartigen und benutzerorientierten mobilen Anwendung zur Effizienzsteigerung in der physiotherapeutischen Dokumentation verwendet werden.
The 3GPP release 16 integrates TSN functionality into 5G and standardizes various options for TSN time synchronization over 5G such as transparent mode and bridge mode. The time domains for the TSN network and the 5G network are kept separate with an option to synchronize either of the networks to the other. The TSN time synchronization over 5G is possible either by using the IEEE 1588 generalized Precision Time Protocol (gPTP) based on UDP/IP multicast or via IEEE 802.1AS based on Ethernet PDUs. The INET and Simu5G simulation frameworks, which are both based on the OMNeT++ discrete event simulator, are widely used for simulating TSN and 5G networks. The INET framework comprises the 802.1AS based time synchronization mechanism, and Simu5G provides the 5G user plane carrying IP PDUs. We modified the 802.1AS-based synchronization model of INET so that it works over UDP/IP. With that, it is possible to synchronize TSN slaves (connected to 5G UEs), across a 5G network, with a TSN master clock, present within a TSN network, that is connected to the 5G core network. Our simulation results show that 500 microseconds of synchronization accuracy can be achieved with the corrected asymmetric propagation delay of uplink and downlink between the gNodeB (gNB) and the User Equipment (UE). Furthermore, the synchronization accuracy can be improved if the delay difference between uplink and downlink is known.
Knowledge of the small-scale nutrient status of arable land is an important basis for optimizing fertilizer use in crop production. A mobile field laboratory opens up the possibility of carrying out soil sampling and nutrient analysis directly on the field. In addition to the benefits of fast data availability and the avoidance of soil material transport to the laboratory, it provides a future foundation for advanced application options, e.g. a high sampling density, sampling of small sub-fields or dynamic adaptation of the sampling line during field sampling. An innovative key component is the NUTRI-STAT ISFET sensor module. It measures values for the ions "NO3- ”, “H2PO4- " and "K+ " as well as the pH. The ISFET sensor module was specially developed for soil nutrient analysis. The phosphorus measurement was further developed for the project "soil2data". First results from the ISFET sensor module show a measurement signal settling time of significantly less than 100 seconds and a further consistent stable measurement signal. The measurement signal dynamics of approx. 58 mV per factor 10 of concentration change is given for the measured variables pH and K+. For the measured quantities of NO3- and H2PO4- , the measurement signal dynamics are lower.
Der Einsatz paralleler Hardware-Architekturen betrifft alle Software-Entwickler und -Entwicklerinnen: vom Supercomputer bis zum eingebetteten System werden Multi- und Manycore-Systeme inzwischen eingesetzt. Die Herausforderungen an das Software Engineering sind vielfältig. Zum einen ist (wieder) ein stärkeres Verständnis für die Hardware notwendig. Ohne eine skalierbare Partitionierung der Software und parallele Algorithmen bleibt die Rechenleistung ungenutzt. Zum anderen stehen neue Programmiersprachen im Vordergrund, die die Ausführung von parallelen Anweisungen ermöglichen.
Dieses Buch betrachtet unterschiedliche Aspekte bei der Entwicklung paralleler Systeme und berücksichtigt dabei auch eingebettete Systeme. Es verbindet Theorie und praktische Anwendung und ist somit für Studierende und Anwender in der Praxis gleichermaßen geeignet. Durch die programmiersprachenunabhängige Darstellung der Algorithmen können sie leicht für die eigene Anwendung angepasst werden. Viele praktische Projekte erleichtern das Selbststudium und vertiefen das Gelernte.
Recent real-time networking developments have enabled ultra reliability, very low latency and high data rates in wired networks. Wireless networking developments have also shown that they can achieve very high data rates with consistency, but they still lack in providing ultra reliability and extremely low latency. Time Sensitive Networking (TSN) developments have brought these capabilities in Industry automation and Automotive industry too. Although TSN is standardized for wired networks for a long time, for wireless networks it will be standardized within the IEEE 802.11be standard for Wi-Fi and 3GPP Release 17 for 5G in the near future. This paper provides an overview of TSN in wired and wireless networks with the aim of comparing different simulators and presenting their offered functionality and shortcomings. These tools can be used to make oneself familiar with TSN algorithms, standards, and for the development and testing of time sensitive networks. Afterwards, the paper discusses open research questions for using TSN over wireless networks.
The effects of reaction parameters on Hurn:xwiley:23670932:media:cptc202000216:cptc202000216-math-0001 production from ethanol photocatalysis in the gas phase have been investigated. The photocatalytic activity evolves from an early mass‐transfer limited regime to an independent one at later irradiation times, which is interpreted in terms of a photocatalytic site activity distribution. Ethanol molar fraction exhibits two different domains, with Hurn:xwiley:23670932:media:cptc202000216:cptc202000216-math-0002 production increasing up to a molar fraction of 0.12, beyond which it plateaus. Hurn:xwiley:23670932:media:cptc202000216:cptc202000216-math-0003 :AcH ratios are very sensitive to reaction conditions, reaching 1.8 at low reactant flows. UV light is converted to Hurn:x-wiley:23670932:media:cptc202000216:cptc202000216-math-0004 with an efficiency of nearly 3 %.
Long Range Wide Area Network (LoRaWAN) operates in the ISM band with 868 MHz, where the Time on Air (ToA) is regulated in the EU to 1 %. LoRaWAN nodes use the Adaptive Data Rate (ADR) algorithm to adapt their data rates during operation. The standard ADR algorithm works well with stationary nodes, however is very slow in the adaptation for mobile nodes. This paper introduces a new ADR algorithm for LoRaWAN that is supported by higher level meta-data for sensor streams, namely Quality of Information (QoI). With the help of QoI it is possible to provide additional information to the new ADR algorithm, reducing the convergence time and thus improving the Packet Delivery Ratio (PDR) of data from mobile sensor nodes. The new algorithm requires only modifications on network server side and keeps backwards compatibility with LoRaWAN nodes. Results show a significant better PDR compared to the standard ADR in scenarios with a limited number of mobile nodes.
Due to the resource-constrained nature of embedded systems, it is crucial to support the estimation of their power consumption as early in the development process as possible. Non-functional requirements based on power consumption directly impact the software design, e.g., watt-hour thresholds and expected lifetimes based on battery capacities. Even if software affects hardware behavior directly, these types of requirements are often overlooked by software developers because they are commonly associated with the hardware layer. Modern trends in software engineering such as Model-Driven Development (MDD) can be used in embedded software development to evaluate power consumption-based requirements in early design phases. However, power consumption aspects are currently not sufficiently considered in MDD approaches. In this paper, we present a model-driven approach using Unified Modeling Language profile extensions to model hardware components and their power characteristics. Software m odels are combined with hardware models to achieve a system-wide estimation, including peripheral devices, and to make the power-related impact in early design stages visible. By deriving energy profiles, we provide software developers with valuable feedback, which may be used to identify energy bugs and evaluate power consumption-related requirements. To demonstrate the potential of our approach, we use a sensor node example to evaluate our concept and to identify its energy bugs.
Optimised Nutrient Recovery from Biogas Digestate by Solid/Liquid Separation and Membrane Treatment
(2019)
Anaerobic digestion products of agricultural biogas plants are characterised by high nitrogen, phosphorus, and potassium content. In three scale-up steps, a membrane based digestate treatment process of solid-liquid-separation, ultrafiltration, and reverse osmosis for nutrient recovery was investigated. Lab-scale trials delivered a very good understanding of fluid properties and subsequent ultrafiltration performance, which is the limiting process step in terms of energy demand and operation costs. In semi-technical experiments, optimisation, and design parameters were developed, which were subsequently applied to pilot-scale tests at two full-scale biogas plants. The process optimisation resulted in 50 % energy reduction of the ultrafiltration step. About 36 % of the sludge volume was recovered as dischargeable water, 20 % as solid N/P-fertiliser, and 44 % as liquid N/K-fertiliser.
Biogas plants produce nutrient rich digestates as side products, which are usually used as local fertilisers. Yet the large amount and regional gradients of biogas plants in Germany necessitate management, conditioning, and transportation of digestates, in order to follow good fertilising procedure and prohibit local over-fertilisation. With a membrane-based treatment chain, i.e. centrifugation, ultrafiltration, and reverse osmosis, digestates can be separated into a solid N,P-fertiliser, a liquid N,K-fertiliser, and dischargeable water. Up to now, the high energy demand of the process chain, in particular the ultrafiltration step, limits the economical market launch of the treatment chain. A reduction of the energy demand is challenging, as digestates exhibit a high fouling potential and ultrafiltration fluxes differ considerably for digestates from different biogas plants. In a systematic screening of 28 digestate samples from agricultural biogas plants and 6 samples from bio-waste biogas plants, ultrafiltration performance could be successfully linked to the rheological properties of the digestate’s liquid phase and to its macromolecular biopolymer concentration. By modification of the fluid characteristics through enzymatic treatment, ultrafiltration performance was considerably increased by factor 2.8 on average, which equals energy savings in the ultrafiltration step of approximately 45%. Consequently, the energy demand of the total treatment chain decreases, which offers potential for further rollout of the membrane-based digestate treatment.
Knowledge of the maximum friction coefficient µmax between tire and road is necessary for implementing autonomous driving. As this coefficient cannot be measured via existing serial vehicle sensors, µmax estimation is a challenging field in modern automotive research. In particular, model-based approaches are applied, which are limited in the estimation accuracy by the physical vehicle model. Therefore, this paper presents a data-based µmax estimation using serial vehicle sensors. For this purpose, recurrent artificial neural networks are trained, validated, and tested based on driving maneuvers carried out with a test vehicle showing improved results compared to the model-based algorithm from previous works.
This paper presents a framework for OMNeT++ which includes time synchronization model for WLANs. Synchronization is based on the Generalized Precision Time Protocol (gPTP) standard, which aims to achieve an accuracy of less than 100 nanoseconds. The presented model is developed and implemented in OMNeT++, a discrete event network simulator, using its INET library. A new type of WLAN node is modeled which supports time synchronization at the Link layer. A clock module for WLAN nodes is also modeled which implements variable clock drift to simulate noise interference in clock frequency oscillators. Simulations with our WLAN nodes are done and the results show that using gPTP based time synchronization in wireless networks, accuracy of ±3ns can be achieved.
Auf vielen Landmaschinen wird der CAN-Bus zur Übertragung von Daten zwischen Sensoren, Aktoren und Steuergeräten genutzt. Anwendungen wie Rückfahrkameras und Bird-ViewAnzeigen erfordern in der Regel zusätzliche, breitbandige Kommunikationskanäle. Dieser Beitrag untersucht, inwieweit ein gemeinschaftliches Kommunikationsmedium auf Basis von Ethernet zur Realisierung aktueller und zukünftiger Anwendungen auf Landmaschinen genutzt werden kann. Zusätzlich wird der Einsatz aktueller Technologien wie Audio/Video Bridging, Time-Sensitive Networking und Wifi auf einem Landmaschinengespann untersucht und bewertet.
Various overoxidized poly(1H-pyrrole) (PPy), poly(N-methylpyrrole) (PMePy) or poly(3,4-ethylenedioxythiophene) (PEDOT) membranes incorporated into an acrylate-based solid polymer electrolyte matrix (SPE) were directly electrosynthesized by a two-step in situ procedure. The aim was to extend and improve fundamental properties of pure SPE materials. The polymer matrix is based on the cross-linking of glycerol propoxylate (1PO/OH) triacrylate (GPTA) with poly(ethylene glycol) diacrylate (PEGDA) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as a conducting salt. A self-standing and flexible polymer electrolyte film is formed during the UV-induced photopolymerization of the acrylate precursors, followed by an electrochemical polymerization of the conducting polymers to form a 3D-IPN. The electrical conductivity of the conducting polymer is destroyed by electrochemical overoxidation in order to convert the conducting polymer into an ion-exchange membrane by introduction of electron-rich groups onto polymer units. The resulting polymer films were characterized by scanning electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy, differential scanning calorimetry, thermal analysis and infrared spectroscopy. The results of this study show that the combination of a polyacrylate-matrix with ion selective properties of overoxidized CPs leads to new 3D materials with higher ionic conductivity than SPEs and separator or selective ion-exchange membrane properties with good stability by facile fabrication.
The present study gives an overview of recent investigations dealing with the fatigue behaviour of the tempered martensitic steel 50CrMo4 (Fe-0.5wt%C-1wt%Cr) in the HCF and VHCF regime by taking into account a variation in material strength, by modifying the heat treatment parameters. The parameters for the tempering treatment were adapted to receive two material conditions with 37HRC and 57HRC, respectively. Subsequently, fatigue specimens were machined from the heat-treated bars for fatigue tests in an ultrasonic (f=20000Hz) and a resonance (f=95Hz) fatigue testing machine under fully reversed loading (R=-1) at laboratory air atmosphere. It was found that the dominant fatigue and fracture mechanisms change with increasing material strength. For 37HRC moderate-strength specimens crack initiation was shown to occur on the specimen surface within Cr depleted bands (segregation bands) as the dominant fatigue damage mechanism. Contrary to that, only internal crack initiation at non-metallic inclusions was observed for the high strength 57HRC condition. Furthermore, the completely different crack initiation mechanisms of the two heat treatment conditions were assessed by applying the Murakami approach relating the fatigue limit with the size of non-metallic inclusions.
Die Anforderungen an zukünftige Teilnehmende eines Arbeitsmarktes verändern sich. Das von Frithjof Bergmann begründete Prinzip der Neuen Arbeit (Bergmann, 2004) ist aktuell Gegenstand zahlreicher Diskussionen und Debatten über aktuelle und zukünftige Arbeitswelten. Die sich daraus ergebenden Kompetenzanforderungen passen mit der Lehre in Hochschulen wenig zusammen. Zunehmend werden agile Lernszenarien diskutiert.
Das Inverted Classroom Modell (ICM) erfreut sich seit einigen Jahren großer Beliebtheit in der Hochschullehre. Aus Studierendensicht ist die Teilnahme an einer ICM-Veranstaltung aber eine Herausforderung. Für ein erfolgreiches Lernen sind insbesondere personale Kompetenzen wie Selbstmotivation, Durchhaltevermögen und Selbstregulationskompetenz erforderlich (Pöpel & Morisse, 2019). Um diesem Umstand entgegenzuwirken, wurde vom Autor ICM mit Ideen aus Scrum für eine Informatik-Lehrveranstaltung kombiniert (siehe auch (Morisse & Heidemann, 2021)). Die Wirkung von Scrum kann sich nur entfalten, wenn die Arbeit in einzelne Sprints aufgeteilt wird und bei der Bearbeitung der Sprints auch die eigene Zusammenarbeit im Rahmen einer Retrospektive kritisch reflektiert wird. Zu diesem Zweck wird der gesamte Inhalt der Lehrveranstaltung in eine Anzahl von thematischen Blöcken aufgeteilt, die als Lehr- und Lerninhalte für die Lern-Sprints der Scrum-Umsetzung werden. Für jeden Themenblock müssen die theoretischen Inhalte erarbeitet sowie eine eigenständige Zusammenfassung formuliert werden. Ergänzend dazu wurde ein Software-Produkt definiert, in dessen Rahmen die theoretischen Inhalte einfließen konnten.
Die Durchführung eines Reviews und einer Retrospektive schließen bei Scrum einen Sprint ab. Genau dies lässt sich auch im Hochschulkontext sehr gut als Feedback-Instrument durchführen. Das Review bestand in der Inspektion der entwickelten Software. Mit der Retrospektive wird die eigene Zusammenarbeit im Team kritisch reflektiert. Ein besonderes Augenmerk verdient der kommunikative Stil zwischen Lehrenden und Studierenden. Bei einem Veranstaltungskonzept, welches getragen wird von Interaktion und Diskussion, kommt einer empathischen und wertschätzenden Kommunikation eine besondere Bedeutung zu. Das dies in der vorgestellten Veranstaltung scheinbar gelungen ist, zeigt das Zitat eines der teilnehmenden Studierenden „Ich freue mich immer auf die Review-Termine“. Zur Erinnerung: Das Review ist der Termin zur Vorstellung des erreichten Ergebnisses, also eher ein Prüfungs-Setting, bei dem Studierende ihre Arbeit präsentieren. Weitere positive Resonanzmerkmale durch die Studierenden waren die hoffnungsvollen Fragen, ob denn die Veranstaltungen im kommenden Semester auch nach ICMScrum organisiert sind.
Der Beitrag beschreibt als Werkstattbericht die Kombination des Inverted Classroom Modells mit der agilen Entwicklungsmethodik von Scrum zu einem Veranstaltungskonzept für ein Grundlagenfach der Informatik. Neben der fachspezifischen Lehre wird dadurch das Vorgehen die in der Informatik immer wichtiger werdende agile Entwicklungsmethodik zum überfachlichen Kompentenzerwerb adressiert. Der Beitrag stellt die Umsetzung der agilen Lehrmethodik vor und gibt erste Rückmeldungen aus Sicht von Studierenden und Lehrenden.