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Wie man die Vorlesung "Technische Mechanik 1 - Statik" für alle Beteiligten dynamisch gestaltet
(2017)
Lehrende nehmen vielfältige Veränderungen, insbesondere bei Studienanfängern wahr: Vorkenntnisse, Aufnahme- und Konzentrationsfähigkeit werden zunehmend heterogener. In der Vorlesung „Technische Mechanik 1“ wurde darauf konstruktiv reagiert, indem der Ablauf und die Struktur verändert wurden. Aufgaben und ihre Lösungen stehen im Mittelpunkt des Unterrichts. Neben der Lehrenden als aktiv Handelnde wird jeder Studierende im Lauf des Semesters in den Ablauf integriert und muss individuelle Lösungen der verteilten Aufgaben präsentieren. Im Vergleich entwickeln die Studierenden durch „Lernen am Modell“ dadurch ihre methodischen und fachlichen Fähigkeiten weiter. Um den Studierenden die Relevanz der behandelten Themenbereiche zu verdeutlichen wurden spezielle Aufgaben mit einem lebensweltlichem Bezug entwickelt. Befragungen zeigen, dass die Studierenden von den vielfältigen interaktiven Lernangeboten profitieren und die entwickelten Kompetenzen auch auf andere Lernsituationen übertragen.
A novel approach of a test environment for embedded networking nodes has been conceptualized and implemented. Its basis is the use of virtual nodes in a PC environment, where each node executes the original embedded code. Different nodes run in parallel, connected via so-called virtual channels. The environment allows to modifying the behavior of the virtual channels as well as the overall topology during runtime to virtualize real-life networking scenarios. The presented approach is very efficient and allows a simple description of test cases without the need of a network simulator. Furthermore, it speeds up the process of developing new features as well as it supports the identification of bugs in wireless communication stacks. In combination with powerful test execution systems, it is possible to create a continuous development and integration flow.
Three real-lab trigeneration microgrids are investigated in non-residential environments (educational, office/administrational, companies/production) with a special focus on domain-specific load characteristics. For accurate load forecasting on such a local level, à priori information on scheduled events have been combined with statistical insight from historical load data (capturing information on not explicitly-known consumer behavior). The load forecasts are then used as data input for (predictive) energy management systems that are implemented in the trigeneration microgrids. In real-world applications, these energy management systems must especially be able to carry out a number of safety and maintenance operations on components such as the battery (e.g. gassing) or CHP unit (e.g. regular test runs). Therefore, energy management systems should combine heuristics with advanced predictive optimization methods. Reducing the effort in IT infrastructure the main and safety relevant management process steps are done on site using a Smart & Local Energy Controller (SLEC) assisted by locally measured signals or operator given information as default and external inputs for any advanced optimization. Heuristic aspects for local fine adjustment of energy flows are presented.
Practical bottlenecks associated with commercialization of Lithium-air cells include capacity limitation and low cycling efficiency. The origin of such losses can be traced to complex electrochemical side reactions and reactant mass transport losses[1]. The efforts to minimize such losses include exploration of various electrolytes with additives[2], and cell component geometry and material design. Given the wide range of options for such materials, it is almost impractical to experimentally setup and characterize all those cells. Consequently, modeling and simulation studies are efficient alternatives to analyze spatially and temporally resolved cell behavior for various combinations of materials[3]. In this study, with the help of a two-dimensional multi physics model, we have focused on the effect of electrode and electrolyte interaction (electrochemistry), choice of electrolyte (species transport), and electrode geometry (electrode design) on the performance of a lithium-air button cell. Figure1a shows the schematics of the 2D axisymmetric computational domain. A comparative analysis of five different electrolytes was performed while focusing on the 2D distribution of local current density and the concentration of electro-chemically active species in the cell, that is, O2and Li+. Using two different cathode configurations, namely, flooded electrode and gas diffusion electrode (GDE)[4] at different cathode thickness, the effect of cell geometry and electrolyte saturation on cell performance was explored. Further, a detailed discussion on electrode volume utilization (cf. Figure1b) is presented via changes in the active volume of cathode that produces 90% of the total current with the cell current density for different combinations of electrolyte saturations and cathode thickness.
This paper describes the Sweaty II humanoid adult size robot trying to qualify for the RoboCup 2017 adult size humanoid competition. Sweaty came 2nd in RoboCup 2016 adult size league. The paper describes the main characteristics of Sweaty that made this success possible, and improvements that have been made or are planned to be implemented for RoboCup 2017.
In this TDP we describe a new tool created for testing the strategy layer of our soccer playing agents. It is a complete 2D simulator that simulates the games based on the decisions of 22 agents. With this tool, debugging the decision and strategy layer of our agents is much more efficient than before due to various interaction methods and complete control over the simulation.
In the future, the tool could also serve as a measure to run simulations of game series much faster than with the 3D simulator. This way, the impact of different play strategies could be evaluated much faster than before.
Gelingt den Studienanfängern eine strukturierte Ergebnissicherung der Lehrveranstaltungen? Oder sind viele allein schon mit einem vollständigen Mitschrieb überfordert? Laufen aktivierende Methoden, Medienwechsel und der Wunsch nach strukturierter Sicherung der Inhalte des Lehrgesprächs teilweise sogar auseinander? Immer mehr Studierende (möchten) auch per Tablet mitschreiben. Wie könnte man in der Lehre auf diese Aspekte stärker eingehen?
Es wird ein praktischer Ansatz gezeigt, Mathematik-Vorlesungen über ein Tablet-basiertes Mitmach-Skript zu gestalten. Dieses dient als Schrittmacher zwischen Input- und Verarbeitungsphasen und unterstützt die strukturierte Verschriftlichung, indem es Vorteile von Tafel, PPT und klassischem Skript vereint. Traditionelle Methoden werden mit technologischen Möglichkeiten kombiniert, um die angesprochenen Herausforderungen bewusster im Lehrstil zu berücksichtigen. Verbindungen zu Virtual Classroom und Video-gestützter Lehre werden aufgezeigt.
Technology and computer applications influence our daily lives and questions arise concerning the role of artificial intelligence and decision-making algorithms. There are warning voices, that computers can, in theory, emulate human intelligence-and exceed it. This paper points out that a replacement of humans by computers is unlikely, because human thinking is characterized by cognitive heuristics and emotions, which cannot simply be implemented in machines operating with algorithms, procedural data processing or artificial neural networks. However, we are going to share our responsibilities with superior computer systems, which are tracking and surveying all of our digital activities, whereas we have no idea of the decision-making processes inside the machines. It is shown that we need a new digital humanism defining rules of computer responsibilities to avoid digital totalism and comprehensive monitoring and controlling of individuals within the planet Earth.
Gamifying rehabilitation is an efficient way to improve motivation and exercise frequency. However, between flow theory, self-determination theory or Bartle's player types there is much room for speculation regarding the mechanics required for successful gamification, which in turn leads to increased motivation. For our study, we selected a gamified solution for motion training (an exergame) where the playful design elements are extremely simple. The contribution is three-fold: we show best practices from the state of the art, present a study analyzing the effects of simple gamification mechanics on a quantitative and on a qualitative level and discuss strategies for playful design in therapeutic movement games.
Spectral analysis of signal averaging electrocardiography in atrial and ventricular tachyarrhythmias
(2017)
Background: Targeting complex fractionated atrial electrograms detected by automated algorithms during ablation of persistent atrial fibrillation has produced conflicting outcomes in previous electrophysiological studies. The aim of the investigation was to evaluate atrial and ventricular high frequency fractionated electrical signals with signal averaging technique.
Methods: Signal averaging electrocardiography (ECG) allows high resolution ECG technique to eliminate interference noise signals in the recorded ECG. The algorithm uses automatic ECG trigger function for signal averaged transthoracic, transesophageal and intracardiac ECG signals with novel LabVIEW software (National Instruments, Austin, Texas, USA). For spectral analysis we used fast fourier transformation in combination with spectro-temporal mapping and wavelet transformation for evaluation of detailed information about the frequency and intensity of high frequency atrial and ventricular signals.
Results: Spectral-temporal mapping and wavelet transformation of the signal averaged ECG allowed the evaluation of high frequency fractionated atrial signals in patients with atrial fibrillation and high frequency ventricular signals in patients with ventricular tachycardia. The analysis in the time domain evaluated fractionated atrial signals at the end of the signal averaged P-wave and fractionated ventricular signals at the end of the QRS complex. The analysis in the frequency domain evaluated high frequency fractionated atrial signals during the P-wave and high frequency fractionated ventricular signals during QRS complex. The combination of analysis in the time and frequency domain allowed the evaluation of fractionated signals during atrial and ventricular conduction.
Conclusions: Spectral analysis of signal averaging electrocardiography with novel LabVIEW software can utilized to evaluate atrial and ventricular conduction delays in patients with atrial fibrillation and ventricular tachycardia. Complex fractionated atrial electrograms may be useful parameters to evaluate electrical cardiac arrhythmogenic signals in atrial fibrillation ablation.
Simulation-based degradation assessment of lithium-ion batteries in a hybrid electric vehicle
(2017)
The insufficient lifetime of lithium-ion batteries is one of the major cost driver for mobile applications. The battery pack in vehicles is one of the most expensive single components that practically must be excluded from premature replacement (i.e., before the life span of the other components end). Battery degradation is a complex physicochemical process that strongly depends on operating condition and environment. We present a simulation-based analysis of lithium-ion battery degradation during operation with a standard PHEV test cycle. We use detailed multiphysics (extended Newman-type) cell models that allow the assessment of local electrochemical potential, species and temperature distributions as driving forces for degradation, including solid electrolyte interphase (SEI) formation [1]. Fig. 1 shows an exemplary test cycle and the predicted resulting spatially-averaged SEI formation rate. We apply a time-upscaling approach to extrapolate the degradation analysis over long time scales, keeping physical accuracy while allowing end-of-life assessment [2]. Results are presented for lithium-ion battery cells with graphite/LFP chemistry. The behavior of these cells in terms of degradation propensity, performance, state of charge and other internal states is predicted during long-term cycling. State of health (SOH) is quantified as capacity fade and internal resistance increase as function of operation time.
Simulation-based degradation assessment of lithium-ion batteries in a hybrid electric vehicle
(2017)
The electrical field (E-field) of the biventricular (BV) stimulation is important for the success of cardiac resynchronization therapy (CRT) in patients with cardiac insufficiency and widened QRS complex.
The aim of the study was to model different pacing and ablation electrodes and to integrate them into a heart model for the static and dynamic simulation of BV stimulation and HF ablation in atrial fibrillation (AF).
The modeling and simulation was carried out using the electromagnetic simulation software CST. Five multipolar left ventricular (LV) electrodes, four bipolar right atrial (RA) electrodes, two right ventricular (RV) electrodes and one HF ablation catheter were modelled. A selection were integrated into the heart rhythm model (Schalk, Offenburg) for the electrical field simulation. The simulation of an AV node ablation at CRT was performed with RA, RV and LV electrodes and integrated ablation catheter with an 8 mm gold tip.
The BV stimulation were performed simultaneously at amplitude of 3 V at the LV electrode and 1 V at the RV electrode with a pulse width of 0.5 ms each. The far-field potential at the RA electrode tip was 32.86 mV and 185.97 mV at a distance of 1 mm from the RA electrode tip. AV node ablation was simulated with an applied power of 5 W at 420 kHz at the distal ablation electrode. The temperature at the catheter tip was 103.87 °C after 5 s ablation time and 37.61 °C at a distance of 2 mm inside the myocardium. After 15 s, the temperature was 118.42 °C and 42.13 °C.
Virtual heart and electrode models as well as the simulations of electrical fields and temperature profiles allow the static and dynamic simulation of atrial synchronous BV stimulation and HF ablation at AF and could be used to optimize the CRT and AF ablation.
Background: The electrical field (E-field) of the biventricular (BV) stimulation is essential for the success of cardiac resynchronization therapy (CRT) in patients with cardiac insufficiency and widened QRS complex. 3D modeling allows the simulation of CRT and high frequency (HF) ablation.
Purpose: The aim of the study was to model different pacing and ablation electrodes and to integrate them into a heart model for the static and dynamic simulation of BV stimulation and HF ablation in atrial fibrillation (AF).
Methods: The modeling and simulation was carried out using the electromagnetic simulation software. Five multipolar left ventricular (LV) electrodes, one epicardial LV electrode, four bipolar right atrial (RA) electrodes, two right ventricular (RV) electrodes and one HF ablation catheter were modeled. Different models of electrodes were integrated into a heart rhythm model for the electrical field simulation (fig.1). The simulation of an AV node ablation at CRT was performed with RA, RV and LV electrodes and integrated ablation catheter with an 8 mm gold tip.
Results: The RV and LV stimulation were performed simultaneously at amplitude of 3 V at the LV electrode and 1 V at the RV electrode, each with a pulse width of 0.5 ms. The far-field potentials generated by the BV stimulations were perceived by the RA electrode. The far-field potential at the RA electrode tip was 32.86 mV. A far-field potential of 185.97 mV resulted at a distance of 1 mm from the RA electrode tip. AV node ablation was simulated with an applied power of 5 W at 420 kHz at the distal 8 mm ablation electrode. The temperature at the catheter tip was 103.87 ° C after 5 s ablation time, 44.17 ° C from the catheter tip in the myocardium and 37.61 ° C at a distance of 2 mm. After 10 s, the temperature at the three measuring points described above was 107.33 ° C, 50.87 ° C, 40.05 ° C and after 15 seconds 118.42 ° C, 55.75 ° C and 42.13 ° C.
Conclusions: Virtual heart and electrode models as well as the simulations of electrical fields and temperature profiles allow the static and dynamic simulation of atrial synchronous BV stimulation and HF ablation at AF. The 3D simulation of the electrical field and temperature profile may be used to optimize the CRT and AF ablation.
Sichere Detektion von Menschen in der Mensch-Roboter-Kollaboration mit Time-of-Flight Kameras
(2017)
Die in dieser Arbeit vorgestellte Vorgehensweise erlaubt die Ortung von Schienenfahrzeugen in topologischen Karten allein mit Hilfe eines Wirbelstromsensorsystems (WSS). Zur Ortung primär erforderlich ist die Identifizierung des befahrenen Gleises selbst, wofür unterschiedliche in einer Karte gespeicherte Merkmale herangezogen werden sowie der zurückgelegte Weg, der durch Zählen der passierten Schwellen ermittelt wird. Diese Merkmale werden mittels eigens definierter, virtueller Sensoren aus dem Signal des WSS gewonnen und mittels einem Bayes’schen Formalismus mit den Referenzdaten aus der vorliegenden topologischen Karte abgeglichen. Diese auf virtuellen Sensoren basierende Vorgehensweise erlaubt eine Parallelisierung der Sensorsignalverarbeitung und eine flexible Einbindung von Sensoren in das Ortungssystem. Die Möglichkeit, Weichen mit einer Trefferquote von 99% zu detektieren, erlaubt die Verfolgung der Fahrzeugposition über die gesamte Fahrstrecke hinweg, unter alleiniger Verwendung der vom WSS gelieferten Messdaten.
Qualitative Wissenschaft, künstlerisches Forschen und forschendes Lernen verbinden Erkenntnis aus Praxis und Erfahrung. In der Autoethnographie der eigenen Werkstatt des Hörens wie der Kultur in Studios anderer, wird die noch neue Interdisziplin Sound (Studies) erprobt und vertieft, mit Impulsen für die Praxis und Theorie, von der noch wenig bekannten A/r/t ographie heute, hin zu einer künftig A/R/Tophonie, dem künstlerischen Forschen in der Musik, ebenso wie durch Klang Komposition, Radio Kunst und visuelle Musik.
The growing complexity in RF front-ends, which support carrier aggregation and a growing number of frequency bands, leads to tightened nonlinearity requirements in all sub-components. The generation of third order intermodulation products (IMD3) are typical problems caused by the non-linearity of SAW devices. In the present work, we investigate temperature compensating (TC) SAW devices on Lithium Niobate-rot128YX. An accurate FEM simulation model [1] is employed, which allows to better understand the origin of nonlinearities in such acoustic devices.
In the present work, nonlinearities in temperature compensating (TC) SAW devices are investigated. The materials used are LiNbO₃-rot128YX as the substrate and Copper electrodes covered with a SiO₂-layer as the compensating layer. In order to understand the role of these materials for the nonlinearities in such acoustic devices, a FEM simulation model in combination with a perturbation approach is applied. The nonlinear tensor data of the different materials involved in TC-SAW devices have been taken from literature, but were partially modified to fit experimental data by introducing scaling factors. An effective nonlinearity constant is determined by comparison of nonlinear P-matrix simulations to IMD3 measurements of test filters. By employing these constants in nonlinear periodic P-matrix simulations a direct comparison to nonlinear periodic FEM-simulations yields the scaling factors for the material used. Thus, the contribution of different materials to the nonlinear behavior of TC-SAW devices is obtained and the role of metal electrodes is discussed in detail.
Our university carries out various research projects. Among others, the project Schluckspecht is an interdisciplinary work on different ultra-efficient car concepts for international contests. Besides the engineering work, one part of the project deals with real-time data visualization. In order to increase the efficiency of the vehicle, an online monitoring of the runtime parameters is necessary. The driving parameters of the vehicle are transmitted to a processing station via a wireless network connection. We plan to use an augmented reality (AR) application to visualize different data on top of the view of the real car. By utilizing a mobile Android or iOS device a user can interactively view various real-time and statistical data. The car and its components are meant to be augmented by various additional information, whereby that information should appear at the correct position of the components. An engine e.g. could show the current rpm and consumption values. A battery on the other hand could show the current charge level. The goal of this paper is to evaluate different possible approaches, their suitability and to expand our application to other projects at our university.
The aim of the smart grid is to achieve more efficient, distributed and secure supply of energy over the traditional power grid by using a bidirectional information flow between the grid agents (e.g. generator node, customer). One of the key optimization problems in smart grid is to produce power among generator nodes with a minimum cost while meeting the customer demand, known as Economic Dispatch Problem (EDP). In recent years, many distributed approaches to solve EDP have been proposed. However, protecting the privacy-sensitive data of individual generator nodes has been largely overlooked in the existing solutions. In this work, we show an attack against an existing auction-based EDP protocol considering a non-colluding semi-honest adversary. We briefly introduce our approach to a practical privacy-preserving EDP solution as our work in progress.
Gaps in basic math knowledge are among the biggest obstacles to a successful start in university. Students starting their studies in STEM disciplines display significant diversity, “math anxiety” is a widespread phenomenon, and the transition to a self-determined way of studying presents a huge challenge. Universities offer support measures such as preparatory courses. Over the years, Offenburg University realized that with increased diversity, traditional ways of teaching in front of the class have become inefficient. The majority of the students remained inactive and just listened to the teachers’ explanations and the few active participants’ answers.
Since 2013 our new course concept fosters a shift from teaching to active learning on a large scale, involving several hundred participants of our on-site preparatory math courses. This switch to broad active practicing, however, must go hand in hand with providing individual support for an increasingly diverse student body. Meanwhile students bring along their mobile devices, and the training App TeachMatics serves as a facilitator. The course concept has been very well received by both students and teachers.
The need to measure basic aerosol parameters has increased dramatically in the last decade. This is due mainly to their harmful effect on the environment and on public health. Legislation requires that particle emissions and ambient levels, workplace particle concentrations and exposure to them are measured to confirm that the defined limits are met and the public is not exposed to harmful concentrations of aerosols.
Climate change and resultant scarcity of water are becoming major challenges for countries around the world. With the advent of Wireless Sensor Networks (WSN) in the last decade and a relatively new concept of Internet of Things (IoT), embedded systems developers are now working on designing control and automation systems that are lower in cost and more sustainable than the existing telemetry systems for monitoring. The Indus river basin in Pakistan has one of the world's largest irrigation systems and it is extremely challenging to design a low-cost embedded system for monitoring and control of waterways that can last for decades. In this paper, we present a hardware design and performance evaluation of a smart water metering solution that is IEEE 802.15.4-compliant. The results show that our hardware design is as powerful as the reference design, but allows for additional flexibility both in hardware and in firmware. The indigenously designed solution has a power added efficiency (PAE) of 24.7% that is expected to last for 351 and 814 days for nodes with and without a power amplifier (PA). Similarly, the results show that a broadband communication (434 MHz) over more than 3km can be supported, which is an important stepping stone for designing a complete coverage solution of large-scale waterways.
Passive hybridization of battery cell and photovoltaic cell: modeling and experimental validation
(2017)
Finding clusters in high dimensional data is a challenging research problem. Subspace clustering algorithms aim to find clusters in all possible subspaces of the dataset where, a subspace is the subset of dimensions of the data. But exponential increase in the number of subspaces with the dimensionality of data renders most of the algorithms inefficient as well as ineffective. Moreover, these algorithms have ingrained data dependency in the clustering process, thus, parallelization becomes difficult and inefficient. SUBSCALE is a recent subspace clustering algorithm which is scalable with the dimensions and contains independent processing steps which can be exploited through parallelism. In this paper, we aim to leverage, firstly, the computational power of widely available multi-core processors to improve the runtime performance of the SUBSCALE algorithm. The experimental evaluation has shown linear speedup. Secondly, we are developing an approach using graphics processing units (GPUs) for fine-grained data parallelism to accelerate the computation further. First tests of the GPU implementation show very promising results.
In this paper we present the implementation of a model-predictive controller (MPC) for real-time control of a cable-robot-based motion simulator. The controller computes control inputs such that a desired acceleration and angular velocity at a defined point in simulator’s cabin are tracked while satisfying constraints imposed by working space and allowed cable forces of the robot. In order to fully use the simulator capabilities, we propose an approach that includes the motion platform actuation in the MPC model. The tracking performance and computation time of the algorithm are investigated in computer simulations. Furthermore, for motion simulation scenarios where the reference trajectories are not known beforehand, we derive an estimate on how much motion simulation fidelity can maximally be improved by any reference prediction scheme compared to the case when no prediction scheme is applied.
Zerstörungsfreie Verfahren zur Messung von Eigenspannungen erfordern, abhängig vom gewählten Verfahren, die Kenntnis gewisser Kopplungskonstanten. Im Falle von Ultraschallmessverfahren sind das neben den elastischen Konstanten zweiter Ordnung (SOEC) vor allem die Konstanten dritter Ordnung (TOEC). Elastische Konstanten fester, metallischer Bauteile werden in der Regel in Zugversuchen bestimmt. Zur Ermittlung der TOEC werden diese mit Ultraschallmessmethoden kombiniert. Durch äußere Einflüsse, wie etwa mechanische Nachbehandlungen der zu untersuchenden Bauteile können sich diese Konstanten jedoch ändern und müssen folglich direkt am veränderten Material bestimmt werden. Mithilfe von Simulationen wird die Ausbreitung der zweiten Harmonischen und der nichtlinear erzeugten Oberflächenwellen in Wellenmischexperimenten analysiert und der akustische Nichtlinearitätsparameter (ANP) bzw. der Kopplungsparameter aus der Amplitudenentwicklung berechnet. Insbesondere wird untersucht, welchen Einfluss ein gegebenes Tiefenprofil der TOEC auf den ANP hat (Vorwärtsproblem) und inwiefern sich aus den Messungen des ANP auf ein vorliegendes Tiefenprofil der TOEC schließen lässt (inverses Problem). Außerdem wird diskutiert, welchen Einfluss lokale Änderungen der SOEC auf den ANP haben können und wie groß diese Änderungen sein dürfen, um die TOEC dennoch bestimmen zu können. Die Untersuchungen hierzu wurden auf der Basis eines 3D-FEM Modells mit zufällig orientierten Mikrorissen durchgeführt. Die numerischen Rechnungen zeigen dabei auch eine gute Übereinstimmung mit einem aus der Literatur bekannten und für dieses Problem erweiterten, analytischen Modell. Neben der rissinduzierten Nichtlinearität kann bei diesem auch die Gitternichtlinearität berücksichtigt werden.
Muli-scale thermos-electrochemical modelling of aging mechanisms in an LFP/graphite lithium-ion cell
(2017)
The paper is addressing the needs of the universities regarding qualification of students as future R&D specialists in efficient techniques for successfully running innovation process. In comparison with the engineers, the students often demonstrate lower motivation in learning systematic inventive techniques, like for example TRIZ methodology, and prefer random brainstorming for idea generation. The quality of obtained solutions also depends on the level of completeness of the problem analysis, which is more complex and time consuming in the case of interdisciplinary systems. The paper briefly describes one-semester-course of 60 hours in new product development with the Advanced Innovation Design Approach and TRIZ methodology, in which a typical industrial innovation process for one selected interdisciplinary mechatronic product is modelled.
Modelling and Simulation of Microscale Trigeneration Systems Based on Real- Life Experimental Data
(2017)
For the shift of the energy grid towards a smarter decentralised system flexible microscale trigeneration systems will play an important role due to their ability to support the demand side management in buildings. However to harness their potential modern control methods like model predictive control must be implemented for their optimal scheduling and control. To implement such supervisory control methods, first, simple analytical models representing the behaviour of the components need to be developed. At the Institute of Energy System Technologies in Offenburg we have built a real-life microscale trigeneration plant and present in this paper the models based on experimental data. These models are qualitatively validated and their application in the future for the optimal scheduling problem is briefly motivated.
Im vorliegenden Beitrag wird ein Strommarktsimulationsmodell entwickelt, mit dessen Hilfe die Bereitstellung von Flexibilität auf dem Strom- und Regelleistungsmarkt in Deutschland modell-gestützt analysiert werden soll. Das Modell bildet dabei zwei parallel verlaufende, zentrale Wettbewerbsmärkte ab, an denen Akteure durch die individuelle Gebotsermittlung handeln können. Die entsprechend hierzu entwickelte Gebotslogik wird detailliert erläutert, wobei der Fokus auf der Flexibilität fossil-thermischer Kraftwerke liegt. In der anschließenden Gegen-überstellung mit realen Marktpreisen zeigt sich, dass die verwendete Methodik und die Ge-botslogik den bestehenden Markt und dessen Marktergebnis in geeigneter Form wiederspie-geln, wodurch zukünftig unterschiedlichste Flexibilitätsszenarien analysiert und Aussagen zu deren Auswirkungen auf den Markt und seine Akteure getroffen werden können.
Message co chairmen
(2017)
The low cost and small size of MEMS inertial sensors allows their combination into a multi sensor module in order to improve performance. However the different linear accelerations measured on different places on a rotating rigid body have to be considered for the proper fusion of the measurements. The errors in measurement of MEMS inertial sensors include deterministic imperfection, but also random noise. The gain in accuracy of using multiple sensors depends strongly on the correlation between these errors from the different sensors. Although for sensor fusion it usually assumed that the measurement errors of different sensors are uncorrelated, estimation theory shows that for the combination of the same type of sensors actually a negative correlation will be more beneficial. Therefore we describe some important and often neglected considerations for the combination of several sensors and also present some preliminary results with regard to the correlation of measurements from a simple multi sensor setup.
Legacy industrial communication protocols are proved robust and functional. During the last decades, the industry has invented completely new or advanced versions of the legacy communication solutions. However, even with the high adoption rate of these new solutions, still the majority industry applications run on legacy, mostly fieldbus related technologies. Profibus is one of those technologies that still keep on growing in the market, albeit a slow in market growth in recent years. A retrofit technology that would enable these technologies to connect to the Internet of Things, utilize the ever growing potential of data analysis, predictive maintenance or cloud-based application, while at the same time not changing a running system is fundamental.
In this paper we show that a model-free approach to learn behaviors in joint space can be successfully used to utilize toes of a humanoid robot. Keeping the approach model-free makes it applicable to any kind of humanoid robot, or robot in general. Here we focus on the benefit on robots with toes which is otherwise more difficult to exploit. The task has been to learn different kick behaviors on simulated Nao robots with toes in the RoboCup 3D soccer simulator. As a result, the robot learned to step on its toe for a kick that performs 30% better than learning the same kick without toes.
The collection of selected papers of the TRIZ Future Conference 2017 is in open access and is included to the Innovator, the journal of the European TRIZ Assocation.
The Bluetooth community is in the process to develop mesh technology. This is highly promising as Bluetooth is widely available in Smart Phones and Tablet PCs, allowing an easy access to the Internet of Things. In this paper work, we investigate the performance of Bluetooth enabled mesh networking that we performed to identify the strengths and weaknesses. A demonstrator for this protocol has been implemented by using the Fruity Mesh protocol implementation. Extensive test cases have been executed to measure the performance, the reliability, the power consumption and the delay. For this, an Automated Physical Testbed (APTB), which emulates the physical channels has been used. The results of these measurements are considered useful for the real implementation of Bluetooth; not only for home and building automation, but also for industrial automation.
Background: Cardiac resynchronization therapy (CRT) with biventricular (BV) pacing is an established therapy for heart failure (HF) patients (P) with sinus rhythm, reduced left ventricular (LV) ejection fraction (EF) and electrical ventricular desynchronization. The aim of the study was to evaluate electrical interventricular delay (IVD) and left ventricular delay (LVD) in right ventricular (RV) pacemaker pacing before upgrading to CRT BV pacing.
Methods: HF P (n=11, age 69.0 ± 7.9 years, 1 female, 10 males) with DDD pacemaker (n=10), DDD defibrillator (n=1), RV pacing, New York Heart Association (NYHA) class 3.0 ± 0.2 and 24.5 ± 4.9 % LVEF were measured by surface ECG and transesophageal bipolar LV ECG before upgrading to CRT defibrillator (n=8) and CRT pacemaker (n=3). IVD was measured between onset of QRS in the surface ECG and onset of LV signal in the transesophageal ECG. LVD was measured between onset and offset of LV signal in the transesophageal ECG. CRT atrioventricular (AV) and BV pacing delay were optimized by impedance cardiography.
Results: Interventricular and intraventricular desynchronization in RV pacemaker pacing were 228.2 ± 44.8 ms QRS duration, 86.5 ± 32.8ms IVD, 94.4 ± 23.8ms LVD, 2.6 ± 0.8 QRS-IVD-ratio with correlation between IVD and QRS-IVD-ratio (r=-0.668 P=0.0248) and 2.3 ± 0.7 QRS-LVD-ratio. The LVEF-IVD-ratio was 0.3 ± 0.1 with correlation between IVD and LVEF-IVD-ratio (r=-0.8063 P=0.00272) and with correlation between QRS duration and LVEF-IVD-ratio (r=-0.7251 P=0.01157). Optimal sensing and pacing AV delay were 128.3 ± 24.8 ms AV delay after atrial sensing (n=6) and 173.3 ± 40.4 ms AV delay after atrial pacing (n=3). Optimal BV pacing delay was -4.3 ± 11.3 ms between LV and RV pacing (n=7). During 30.4 ± 29.6 month CRT follow-up, the NYHA class improved from 3.1 ± 0.2 to 2.2 ± 0.3.
Conclusions: Transesophageal electrical IVD and LVD in RV pacemaker pacing may be additional useful ventricular desynchronization parameters to improve P selection for upgrading RV pacemaker pacing to CRT BV pacing.
Additive manufacturing processes have evolved rapidly in recent years and now offer a wide range of manufacturing technologies and workable materials. This range from plastics and metals to paper and even polymer plaster composites. Due to the layer by layer structure of the components the additive processes have in comparison with conventional manufacturing processes the advantage of freedom of design, that means the simple implementation of complex geometries. Moreover, the additive processes provide the advantage of reduced consumption of resources, since essentially only the material is consumed, which is required for the actual component, since no waste in the form of chips is produced. In order to use these advantages, the potentials of additive manufacturing and the requirements of sustainable design must already be observed in the product development process. So the design of the components and products must be made so as little as possible construction and supporting material is required for the generative production and therefore little resources are consumed. Also, all steps of the additive manufacturing process must be considered properly, that includes the post processing. This allows components be designed so that for instance the effort for removing the support structure is considerably reduced. This leads to a significant reduction in manufacturing time and thus energy consumption. The implementation of these potentials in product development can be demonstrated by means of a multiple-stages model. A case study shows how this model is applied in the training of Master students in the field of product development. In a workshop the students work as a group while implementing the task of developing a miniature racing car under the rules of sustainable design in compliance with the boundary conditions for an additive manufacturing. In this case, Fused Deposition Modelling FDM using plastics as a building material is applied. The results show how the students have dealt with the different requirements and how they have implemented them in product development and in the subsequent additive manufacturing.