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Modelling detailed chemistry in lithium-ion batteries: Insight into performance, ageing and safety
(2018)
A method for determining properties of a pipeline includes feeding a sound wave signal at a predetermined feed point into the pipeline so that the sound wave signal propagates in an axial direction of the pipeline. The frequency spectrum of the transmitted sound wave signal has a frequency component or a spectral range with a maximum frequency that is smaller than the lower limit frequency for the first upper mode. Reflected portions of the transmitted sound wave signal are detected as received sound wave signal and are evaluated with regard to the transmitted sound wave signal to determine at least the distance of each reflection site from the feed point.
The paper describes the methodology and experimental results for revealing similarities in thermal dependencies of biases of accelerometers and gyroscopes from 250 inertial MEMS chips (MPU-9250). Temperature profiles were measured on an experimental setup with a Peltier element for temperature control. Classification of temperature curves was carried out with machine learning approach.
A perfect sensor should not have thermal dependency at all. Thus, only sensors inside the clusters with smaller dependency (smaller total temperature slopes) might be pre-selected for production of high accuracy inertial navigation modules. It was found that no unified thermal profile (“family” curve) exists for all sensors in a production batch. However, obviously, sensors might be grouped according to their parameters. Therefore, the temperature compensation profiles might be regressed for each group. 12 slope coefficients on 5 degrees temperature intervals from 0°C to +60°C were used as the features for the k-means++ clustering algorithm.
The minimum number of clusters for all sensors to be well separated from each other by bias thermal profiles in our case is 6. It was found by applying the elbow method. For each cluster a regression curve can be obtained.
Die traditionellen Geschäftsmodelle der Medienbranche beruhen auf der Werbevermarktung von Spots, Anzeigen und Beilagen und teilweise einem direkten Erlösmodell für journalistische Inhalte durch Subscriber-Modelle/Abonnement bzw. Einzelverkaufserlöse. Diese Geschäftsmodelle verändern sich im Rahmen der digitalen Transformation und der damit verbundenen Medienkonvergenz zugunsten neuer nicht-journalistischer digitaler Geschäftsmodelle. Entscheidend ist eine Analyse der kompletten Geschäftsmodelle vor allem im Hinblick auf die Zielgruppen und den Nutzen der neuen Produkte, bevor der Teilaspekt der unterschiedlichen Erlösmodelle für crossmediale Medien aus der Perspektive der Medienunternehmen geklärt werden kann.
Mediaplanung
(2018)
The authors claim that location information of stationary ICT components can never be unclassified. They describe how swarm-mapping crowd sourcing is used by Apple and Google to worldwide harvest geo-location information on wireless access points and mobile telecommunication systems' base stations to build up gigantic databases with very exclusive access rights. After having highlighted the known technical facts, in the speculative part of this article, the authors argue how this may impact cyber deterrence strategies of states and alliances understanding the cyberspace as another domain of geostrategic relevance. The states and alliances spectrum of activities due to the potential existence of such databases may range from geopolitical negotiations by institutions understanding international affairs as their core business, mitigation approaches at a technical level, over means of cyber deterrence-by-retaliation.
Bank and trust – two words but one meaning in customers’ minds. When interacting with financial service providers, customers are consistently looking for “trust signals” that comfort their decisions and “distrust signals” which create doubt. Therefore, service providers need a deep understanding of the customers’ requirements and wishes. To identify trust and distrust signals, we combine established user experience research methods with a new testing procedure to gain helpful recommendations for optimizing the online appearance of banks. The contribution is divided into three parts: Firstly, we investigate current approaches in the financial service industry. Secondly, we provide a corpus describing the relationship between the customers’ perception of a bank’s website and trust. Thirdly, an empirical study based on qualitative user experience testing with banking website customers shows the value gained by optimizing the banks’ virtual interface by enhancing “trust signals” and avoiding “distrust signals”.
The Transport Layer Security (TLS) protocol is a cornerstone of secure network communication, not only for online banking, e-commerce, and social media, but also for industrial communication and cyber-physical systems. Unfortunately, implementing TLS correctly is very challenging, as becomes evident by considering the high frequency of bugfixes filed for many TLS implementations. Given the high significance of TLS, advancing the quality of implementations is a sustained pursuit. We strive to support these efforts by presenting a novel, response-distribution guided fuzzing algorithm for differential testing of black-box TLS implementations. Our algorithm generates highly diverse and mostly-valid TLS stimulation messages, which evoke more behavioral discrepancies in TLS server implementations than other algorithms. We evaluate our algorithm using 37 different TLS implementations and discuss―by means of a case study―how the resulting data allows to assess and improve not only implementations of TLS but also to identify underspecified corner cases. We introduce suspiciousness as a per-implementation metric of anomalous implementation behavior and find that more recent or bug-fixed implementations tend to have a lower suspiciousness score. Our contribution is complementary to existing tools and approaches in the area, and can help reveal implementation flaws and avoid regression. While being presented for TLS, we expect our algorithm's guidance scheme to be applicable and useful also in other contexts. Source code and data is made available for fellow researchers in order to stimulate discussions and invite others to benefit from and advance our work.
Marketingrecht
(2018)
Markenbewertung
(2018)
Vehicle-to-Everything (V2X) communication promises improvements in road safety and efficiency by enabling low-latency and reliable communication services for vehicles. Besides using Mobile Broadband (MBB), there is a need to develop Ultra Reliable Low Latency Communications (URLLC) applications with cellular networks especially when safety-related driving applications are concerned. Future cellular networks are expected to support novel latencysensitive use cases. Many applications of V2X communication, like collaborative autonomous driving requires very low latency and high reliability in order to support real-time communication between vehicles and other network elements. In this paper, we classify V2X use-cases and their requirements in order to identify cellular network technologies able to support them. The bottleneck problem of the medium access in 4G Long Term Evolution(LTE) networks is random access procedure. It is evaluated through simulations to further detail the future limitations and requirements. Limitations and improvement possibilities for next generation of cellular networks are finally detailed. Moreover, the results presented in this paper provide the limits of different parameter sets with regard to the requirements of V2X-based applications. In doing this, a starting point to migrate to Narrowband IoT (NB-IoT) or 5G - solutions is given.
One of the bottlenecks hindering the usage of polymer electrolyte membrane fuel cell technology in automotive applications is the highly load-sensitive degradation of the cell components. The cell failure cases reported in the literature show localized cell component degradation, mainly caused by flow-field dependent non-uniform distribution of reactants. The existing methodologies for diagnostics of localized cell failure are either invasive or require sophisticated and expensive apparatus. In this study, with the help of a multiscale simulation framework, a single polymer electrolyte membrane fuel cell (PEMFC) model is exposed to a standardized drive cycle provided by a system model of a fuel cell car. A 2D multiphysics model of the PEMFC is used to investigate catalyst degradation due to spatio-temporal variations in the fuel cell state variables under the highly transient load cycles. A three-step (extraction, oxidation, and dissolution) model of platinum loss in the cathode catalyst layer is used to investigate the cell performance degradation due to the consequent reduction in the electro-chemical active surface area (ECSA). By using a time-upscaling methodology, we present a comparative prediction of cell end-of-life (EOL) under different driving behavior of New European Driving Cycle (NEDC) and Worldwide Harmonized Light Vehicles Test Cycle (WLTC).
LG München I "Lieferfrist"
(2018)
LG Frankfurt/M. "Hooligan"
(2018)
Das Standardlehrbuch zum internationalen Steuerrecht
Kenntnisse im internationalen Steuerrecht werden in der steuerlichen Ausbildung immer wichtiger. Mit dem „Wilke“ sichern Sie sich einen umfassenden und fundierten Einstieg in diese komplexe Materie.
Leicht verständlich und anschaulich vermittelt dieses Standardlehrbuch Ihnen alle relevanten Grundlagen des internationalen Steuerrechts. Der Aufbau des Buchs orientiert sich dabei sowohl an den Bedürfnissen der Ausbildung als auch denen der Praxis. Als idealer Begleiter unterstützt es Sie in jeder Phase Ihrer beruflichen Entwicklung – von den ersten Schritten in der Steuerberater-Ausbildung bis hin zur erfolgreich abgeschlossenen Weiterbildung zum Fachberater für Internationales Steuerrecht.
Die 14. Auflage berücksichtigt die Entwicklung auf dem Gebiet des internationalen Steuerrechts in Gesetzgebung, Rechtsprechung, Literatur und Verwaltung bis Ende Oktober 2018.
Rechtsstand: 1.11.2018
The next generation cellular networks are expected to improve reliability, energy efficiency, data rate, capacity and latency. Originally, Machine Type Communication (MTC) was designed for low-bandwidth high-latency applications such as, environmental sensing, smart dustbin, etc., but there is additional demand around applications with low latency requirements, like industrial automation, driver-less cars, and so on. Improvements are required in 4G Long Term Evolution (LTE) networks towards the development of next generation cellular networks for providing very low latency and high reliability. To this end, we present an in-depth analysis of parameters that contribute to the latency in 4G networks along with a description of latency reduction techniques. We implement and validate these latency reduction techniques in the open-source network simulator (NS3) for narrowband user equipment category Cat-Ml (LTE-M) to analyze the improvements. The results presented are a step towards enabling narrowband Ultra Reliable Low Latency Communication (URLLC) networks.
The excessive control signaling in Long Term Evolution networks required for dynamic scheduling impedes the deployment of ultra-reliable low latency applications. Semi-persistent scheduling was originally designed for constant bit-rate voice applications, however, very low control overhead makes it a potential latency reduction technique in Long Term Evolution. In this paper, we investigate resource scheduling in narrowband fourth generation Long Term Evolution networks through Network Simulator (NS3) simulations. The current release of NS3 does not include a semi-persistent scheduler for Long Term Evolution module. Therefore, we developed the semi-persistent scheduling feature in NS3 to evaluate and compare the performance in terms of uplink latency. We evaluate dynamic scheduling and semi-persistent scheduling in order to analyze the impact of resource scheduling methods on up-link latency.
Kundenbindungscontrolling
(2018)
Kundenbindung
(2018)
Kreditsicherungsrecht
(2018)
Kernkompetenz-Management
(2018)
We present a planar chromatographic separation method for the phytoestrogenic active compound equol, separated on RP-18 W (Merck, 1.14296) phase. It could be shown that an ethanolic cattle manure extract contains this phytoestrogenic active compound to a larger amount. As solvents for the mobile phase, hexane, ethyl acetate, and acetone (45:15:10, v/v); acetone and water (15:10, v/v); and n-hexane, CH2Cl2, ethyl acetate, methanol, and formic acid (40:40:20:5:1, v/v) have been used. After separation, a modified yeast estrogen screen (YES) test was applied, using the yeast strain Saccharomyces cerevisiae BJ3505 containing an estrogen receptor. Its activation by equol induces the reporter gene lacZ which encodes the enzyme β-galactosidase. The enzyme activity is measured directly on the TLC plate by using the substrate MUG (4-methylumbelliferyl-β-d-galactopyranoside) or the substrate X-β-Gal (5-bromo-4-chloro-3-indoxyl-β-d-galactopyranoside). β-Galactosidase cleaves MUG into a fluorescing compound. X-β- Gal is also hydrolyzed and then oxidized by oxygen forming the deep-blue dye 5,5′-dibromo-4,4′-dichloro-indigo. Both reactions in combination with a thin-layer chromatography (TLC) separation allow very specific detecting of equol in cattle manure, although that is a very challenging matrix. Preliminary results show that the average content of equol in liquid manure is roughly 60 μg g−1. The value for urine is 50 μg mL−1.
Nonlinearity can give rise to intermodulation distortions in surface acoustic wave (SAW) devices operating at high input power levels. To understand such undesired effects, a finite element method (FEM) simulation model in combination with a perturbation theory is applied to find out the role of different materials and higher order nonlinear tensor data for the nonlinearities in such acoustic devices. At high power, the SAW devices containing metal, piezoelectric substrate, and temperature compensating (TC) layers are subject to complicated geometrical, material, and other nonlinearities. In this paper, third-order nonlinearities in TC-SAW devices are investigated. The materials used are LiNbO 3 -rot128YX as the substrate and copper electrodes covered with a SiO 2 film as the TC layer. An effective nonlinearity constant for a given system is determined by comparison of nonlinear P-matrix simulations to third-order intermodulation measurements of test filters in a first step. By employing these constants from different systems, i.e., different metallization ratios, in nonlinear periodic P-matrix simulations, a direct comparison to nonlinear periodic FEM-simulations yields scaling factors for the materials used. Thus, the contribution of the different materials to the nonlinear behavior of TC-SAW devices is obtained and the role of metal electrodes, substrate, and TC film are discussed in detail.
The Datagram Transport Layer Security (DTLS) protocol has been designed to provide end-to-end security over unreliable communication links. Where its connection establishment is concerned, DTLS copes with potential loss of protocol messages by implementing its own loss detection and retransmission scheme. However, the default scheme turns out to be suboptimal for links with high transmission error rates and low data rates, such as wireless links in electromagnetically harsh industrial environments. Therefore, in this paper, as a first step we provide an analysis of the standard DTLS handshake's performance under such adverse transmission conditions. Our studies are based on simulations that model message loss as the result of bit transmission errors. We consider several handshake variants, including endpoint authentication via pre-shared keys or certificates. As a second step, we propose and evaluate modifications to the way message loss is dealt with during the handshake, making DTLS deployable in situations which are prohibitive for default DTLS.
eLetter zu "Illusory movement perception improves motor control for prosthetic hands" von Paul D. Marasco et al., veröffentlicht in Science Translational Medicine, Vol. 10, No. 432 (DOI: 10.1126/scitranslmed.aao6990)
This paper is discussing the development of a wireless Indoor Smart Gardening System with the focus on energy autonomous working. The Smart Gardening System, which is presented in this paper consists of a network of energy autonomous wireless sensor nodes which are used for monitoring important plant parameters like air temperature, soil moisture, pressure or humidity and in future to control an actuator for the plant irrigation and to measure further parameter as light and fertilizer level. Solar energy harvesting is used for powering the wireless nodes without the usage of a battery. Comparable Smart Gardening Systems are usually battery-powered. Furthermore, the overall Smart Gardening System consists of a battery powered gateway based on a Raspberry Pi 3 system, which controls the wireless nodes and collects their sensor data. The gateway is able to send the information to an internet server application and via Wi-Fi to mobile devices. Particularly the architecture of the energy autonomous wireless nodes will be considered because fully energy autonomous wireless networks could not be implemented without special concepts for the energy supply and architecture of the wireless nodes.
Numerous 2,5-dimethoxy-N-benzylphenethylamines (NBOMe), carrying a variety of lipophilic substituents at the 4-position, are potent agonists at 5-hydroxytryptamine (5HT2A ) receptors and show hallucinogenic effects. The present study investigated the metabolism of 25D-NBOMe, 25E-NBOMe, and 25N-NBOMe using the microsomal model of pooled human liver microsomes (pHLM) and the microbial model of the fungi Cunninghamella elegans (C. elegans). Identification of metabolites was performed using liquid chromatography-high resolution-tandem mass spectrometry (LC-HR-MS/MS) with a quadrupole time-of-flight (QqToF) instrument. In total, 36 25D-NBOMe phase I metabolites, 26 25E-NBOMe phase I metabolites and 24 25N-NBOMe phase I metabolites were detected and identified in pHLM. Furthermore, 14 metabolites of 25D-NBOMe, 11 25E-NBOMe metabolites, and nine 25N-NBOMe metabolites could be found in C. elegans. The main biotransformation steps observed were oxidative deamination, oxidative N-dealkylation also in combination with hydroxylation, oxidative O-demethylation possibly combined with hydroxylation, oxidation of secondary alcohols, mono- and dihydroxylation, oxidation of primary alcohols, and carboxylation of primary alcohols. Additionally, oxidative di-O-demethylation for 25E-NBOMe and reduction of the aromatic nitro group and N-acetylation of the primary aromatic amine for 25N-NBOMe took place. The resulting 25N-NBOMe metabolites were unique for NBOMe compounds. For all NBOMes investigated, the corresponding 2,5-dimethoxyphenethylamine (2C-X) metabolite was detected. This study reports for the first time 25X-NBOMe N-oxide metabolites and hydroxylamine metabolites, which were identified for 25D-NBOMe and 25N-NBOMe and all three investigated NBOMes, respectively. C. elegans was capable of generating all main biotransformation steps observed in pHLM and might therefore be an interesting model for further studies of new psychoactive substances (NPS) metabolism.
Implementation of interdisciplinary student teams in design education for additive manufacturing
(2018)
Additive manufacturing (AM) technologies are becoming increasingly popular in all areas of product development. Therefore, it is imperative that students be taught Design for AM. However, due to the rapid development of new methods and materials for AM, it does not make sense to only teach particular design guidelines, as these can quickly become obsolete. Rather, students should acquire the competence to develop guidelines themselves, that take into account the current state of the art. Thus, they will be able to react to changing processes and new materials
in the future. In order to convey the independent development of design guidelines for additive manufacturing by students, a new concept was developed, which is presented in this contribution. In this process, the learning goal is worked out by a group of students on the basis of a practical
task. The group consists of an interdisciplinary team in order to combine different competencies and to provide different perspectives on the task. A case study will show the design and manufacture of a miniature aircraft using Fused Layer Modelling. The aim of the development is above all the design for additive manufacturing. In addition, a low use of resources in combination with lightweight construction should be achieved. In the implementation of the task, the students are confronted with challenging aerodynamic design of wings as well as with the economic evaluation of the development process. An examination of the level of knowledge before and after the case study examines the learning success.
Various methods of Digital Manufacturing (DM) have been available for the manufacturing of physical architectural models for several years. This paper highlights the advantages of 3D printing for digital manufacturing of detailed architectural models. In particular, the representation of architectural details and textures is treated. Furthermore, two new methods are being developed in order to improve the conditions for the application of digital manufacturing of architectural models.
Identification of Secondary Problems of New Technologies in Process Engineering by Patent Analysis
(2018)
The implementation of new technologies in production plants often causes negative side effects and drawbacks. In this context, the prediction of the secondary problems and risks can be used advantageously for selecting best solutions for intensification of the processes. The proposed method puts primary emphasis on systematic and fast anticipation of secondary problems using patent documents, and on extraction and prediction of possible engineering contradictions within novel technical systems. The approach comprises three ways to find secondary problems: (a) direct knowledge-based identification of secondary problems in new technologies or equipment; (b) identification of secondary problems of prototypes mentioned in patent citation trees; and (c) prediction of negative side effects using the correlation matrix for invention goals and secondary problems in a specific engineering domain.
In the 19th century Alexander von Humboldt explored the nature and was conceived a new vision of nature that still influences the way we understand the new world. Humboldt believed in the importance of accurate measurements and precise description of observations. His vision of nature included not only facts but also emotions.
Nowadays smart solutions will be developed by using computer technology, which will influence our relationship to nature, our handling of the complexity and diversity of nature itself and the technological influences on the society. Could we avoid a new form of “Colonialism”, when a network of super computers will create a smarter world?
Oxide semiconductors are highly promising candidates for the most awaited, next-generation electronics, namely, printed electronics. As a fabrication route for the solution-processed/printed oxide semiconductors, photonic curing is becoming increasingly popular, as compared to the conventional thermal curing method; the former offers numerous advantages over the latter, such as low process temperatures and short exposure time and thereby, high throughput compatibility. Here, using dissimilar photonic curing concepts (UV–visible light and UV-laser), we demonstrate facile fabrication of high performance In2O3 field-effect transistors (FETs). Beside the processing related issues (temperature, time etc.), the other known limitation of oxide electronics is the lack of high performance p-type semiconductors, which can be bypassed using unipolar logics from high mobility n-type semiconductors alone. Interestingly, here we have found that our chosen distinct photonic curing methods can offer a large variation in threshold voltage, when they are fabricated from the same precursor ink. Consequently, both depletion and enhancement-mode devices have been achieved which can be used as the pull-up and pull-down transistors in unipolar inverters. The present device fabrication recipe demonstrates fast processing of low operation voltage, high performance FETs with large threshold voltage tunability.
Hintergrund: Richtung und Stärke des elektrischen Feldes (E-Feld) der biventrikulären (BV) Stimulation und elektrische interventrikuläre Desynchronisation sind bei Patienten mit Herzinsuffizienz und verbreitertem QRS Komplex von Bedeutung für den Erfolg der kardialen Resynchronisationstherapie (CRT). Das 3D Herzrhythmusmodell (HRM) ermöglicht die
Simulation von CRT und Hochfrequenz (HF) Ablation. Das Ziel der Studie besteht in der Integration von Schrittmacher- und Ablationselektroden in das HRM zur E-Feld Simulation der BV Stimulation und thermischen Feld (T-Feld) Simulation der HF Ablation von Vorhofflimmern (AF).
Methoden: Es wurden fünf multipolare linksventrikuläre (LV) Elektroden, eine epikardiale LV Elektrode, vier bipolare rechtsatriale (RA) Elektroden, zwei rechtsventrikuläre (RV) Elektroden und ein HF Ablationskatheter mit CST (Computer Simulation Technology, Darmstadt) modelliert und das HRM (Schalk et al: Clin Res Cardiol 106, Suppl 1, April 2017, P1812) um den Koronarvenensinus (CS) erweitert (HRM-CS). E-Feld Simulationen bei vorhofsynchroner BV Stimulation und bei RA Stimulation mit RV und LV Ableitung erfolgten mit den Elektroden Select Secure 3830, Capsure VDD-2 5038 und Attain OTW 4194 im HRM+CS (Fig.). F-Feld Simulationen der HF Ablation von AF bei CRT wurden mit integriertem Ablationskatheter AlCath G FullCircle (Biotronik) simuliert.
Ergebnisse: HRM-CS ermöglichte 3D E-Feld Simulationen bei vorhofsynchroner bipolarer BV Stimulation und bei bipolarer RA Stimulation mit bipolarer RV und LV Ableitung. RV und LV Stimulation erfolgten zeitgleich bei einer Amplitude von 3 V an der LV Elektrode und 1 V an der RV Elektrode mit einer Impulsbreite von jeweils 0,5 ms. Die von der BV Stimulationen erzeugten Fernpotentiale konnten von der RA Elektrode wahrgenommen werden. Das Fernpotential an der RA Elektrodenspitze betrug 32,86 mV und in 1 mm Abstand von der RA Elektrodenspitze ergab sich ein Fernpotential von 185,97 mV. HRM-CS ermöglichte 3D T-Feld Simulationen der HF Ablation von AF bei CRT. Das T-Feld bei HF Ablation des AV-Knotens wurde mit einer anliegenden Leistung von 5 W bei 420 kHz an der distalen 8 mm Ablationselektrode simuliert. Die Temperatur an der Katheterspitze betrug nach 5 s Ablationsdauer 88,66 °C, in 1 mm Abstand von der Katheterspitze im Myokard 42,17 °C und in 2 mm Abstand 37,49 °C.
Schlussfolgerungen: HRM-CS und Elektrodenmodelle ermöglichen die 3D Simulationen von E-Feldern bei vorhofsynchroner BV Stimulation, RA Stimulation mit RV und LV Wahrnehmung und von T-Feldern bei HF Ablation. E-Feld Simulationen von RA, RV und LV Stimulation und Sensing können möglicherweise zur Vorhersage von CRT Respondern genutzt werden.
Abstract: Electric field of biventricular (BV) pacing, left ventricular (LV) electrode position and electrical interventricular desynchronization are important parameters for successful cardiac resynchronization therapy (CRT) in patients with heart failure, sinus rhythm and reduced LV ejection fraction. The aim of the study was to evaluate electric pacing field of transesophageal left atrial (LA) pacing and BV pacing with 3D heart rhythm simulation. Bipolar right atrial (RA), right ventricular (RV), LV electrodes and multipolar hemispherical esophageal LA electrodes were modeled with CST (Computer Simulation Technology, Darmstadt). Electric pacing field were simulated with bipolar RA and RV pacing with Solid S (Biotronik) electrode, bipolar LV pacing with Attain 4194 (Medtronic) electrode and bipolar LA pacing with TO8 (Osypka) esophageal electrode. 3D heart rhythm model with esophagus allowed electric pacing field simulation of 4-chamber pacing with bipolar intracardiac RA, RV, LV pacing and bipolar transesophageal LA pacing. The pacing amplitudes were 3V RA pacing amplitude, 50V LA pacing amplitude, 1.5V RV pacing amplitude and 3V LV pacing amplitude with 0.5ms pacing pulse duration. The atrioventricular delay between RA pacing and BV pacing was 140ms atrioventricular pacing delay and simultaneous RV and LV pacing. Electric pacing fields were simulated during the different pacing modes AAI, VVI, DDD and DDD0V. The intracardiac far-field pacing potentials were evaluated with intracardiac electrodes and a distance of 1mm from the electrodes with RA electrode 1.104V, RV electrode 0.703V and LV electrode 1.32V. The transesophageal far-field pacing potential was evaluated with transesophageal electrode and a distance of 10mm from the elelctrode with LA electrode 6.076V. Heart rhythm model simulation with esophagus allows evaluation of electric pacing fields in AAI, VVI, DDD, DDD0V and DDD0D pacing modes. Electric pacing field of RA, RV and LV pacing in combination with LA pacing may additional useful pacing mode in CRT non-responders.
Grundzüge der Strömungslehre
(2018)
Dieses ausgereifte Lehrbuch bringt in prägnant kurzer und mathematisch verständlicher Darstellung die strömungstechnischen Grundlagen. In der aktuellen Auflage wurde ein Abschnitt zu Dissipation und Viskosen Potentialströmungen ergänzt. Aufgaben mit Lösungen helfen den Lernstoff richtig anzuwenden und fördern das Verständnis.
Mit Gendering Marteloskope stellen wir Entwicklungsprozess dar: Entstanden ist videografisches Material in Marteloskopen, die im Wald Bäume, Tablets und Menschen in Dialog zueinander setzen. Die Videografie und die Erfahrungen vor Ort werden mit Ansätzen aus Gender in Science and Technlogy Studies reflektiert sowie mit digital unterstützter kollaborativer Didaktik über interaktive Webdokumentationen zu Open Science Modulen zusammengeführt.
Frühwarnsysteme
(2018)
Printed electronics offers certain technological advantages over its silicon based counterparts, such as mechanical flexibility, low process temperatures, maskless and additive manufacturing process, leading to extremely low cost manufacturing. However, to be exploited in applications such as smart sensors, Internet of Things and wearables, it is essential that the printed devices operate at low supply voltages. Electrolyte gated field effect transistors (EGFETs) using solution-processed inorganic materials which are fully printed using inkjet printers at low temperatures are very promising candidates to provide such solutions. In this paper, we discuss the technology, process, modeling, fabrication, and design aspect of circuits based on EGFETs. We show how the measurements performed in the lab can accurately be modeled in order to be integrated in the design automation tool flow in the form of a Process Design Kit (PDK). We also review some of the remaining challenges in this technology and discuss our future directions to address them.
The fisheye camera has been widely studied in the field of ground based sky imagery and robot vision since it can capture a wide view of the scene at one time. However, serious image distortion is a major drawback hindering its wider use. To remedy this, this paperproposes a lens calibration and distortion correction method for detecting clouds and forecasting solar radiation. Finally, the radial distortion of the fisheye image can be corrected by incorporating the estimated calibration parameters. Experimental results validate the effectiveness of the proposed method.
The production of potable water in dry areas nowadays is mainly done by the desalination of seawater. State of the art desalination plants usually are built with high production capacities and consume a lot of electrical energy or energy from primary resources such as oil. This causes difficulties in rural areas, where no infrastructure is available neither for the plants’ energy supply nor the distribution of the produced potable water. To address this need, small, self-sustaining and locally operated desalination plants came into the focus of research. In this work, a novel flash evaporator design is proposed which can be driven either by solar power or by low temperature waste heat. It offers low operation costs as well as easy maintenance. The results of an experimental setup operated with water at a feed flow rate of up to 1,600 l/h are presented. It is shown that the proof of concept regarding efficient evaporation as well as efficient gas-liquid separation is provided successfully. The experimental evaporation yield counts for 98 % of the vapor content that is expected from the vapor pressure curve of water. Neither measurements of the electrical conductivity of the gained condensate, nor the analysis of the vapor flow by optical methods show significant droplet entrainment, so there are no concerns regarding the purity of the produced condensate for the use as drinking water.
Our media-artistic performances and installations, INTERCORPOREAL SPLITS (2010–2013), BUZZ (2014–2015), W ASTELAND (2015–2016), as well as our new collaboration with Bruno Latour , DE\GLOBALIZE (2018–2020), are not just about polyphony. Here, however, we rediscover them under this heading, thus giving them a new twist, while mapping out issues, mechanisms and functional modes of the polyphonic.
Lithium-ion pouch cells with lithium titanate (Li4Ti5O12, LTO) anode and lithium nickel cobalt aluminum oxide (LiNi0.8Co0.15Al0.05O2, NCA) cathode were investigated experimentally with respect to their electrical (0.1C…4C), thermal (5 °C…50 °C) and long-time cycling behavior. The 16 Ah cell exhibits an asymmetric charge/discharge behavior which leads to a strong capacity-rate effect, as well as a significantly temperature-dependent capacity (0.37 Ah ∙ K−1) which expresses as additional high-temperature feature in the differential voltage plot. The cell was cycled for 10,000 cycles inbetween the nominal voltage limits (1.7–2.7 V) with a symmetric 4C constant-current charge/discharge protocol, corresponding to approx. 3400 equivalent full cycles. A small (0.192 mΩ/1000 cycles) but continuous increase of internal resistance was observed. Using electrochemical impedance spectroscopy (EIS), this could be identified to be caused by the NCA cathode, while the LTO anode showed only minor changes during cycling. The temperature-corrected capacity during 4C cycling exhibited a decrease of 1.28%/1000 cycles. The 1C discharge capacity faded by only 4.0% for CC discharge and 2.3% for CCCV discharge after 10,000 cycles. The cell thus exhibits very good internal-resistance stability and excellent capacity retention even under harsh (4C continuous) cycling, demonstrating the excellent stability of LTO as anode material.
Die Frage nach der Erforderlichkeit der Benennung eines Datenschutzbeauftragten wird derzeit oft gestellt. Der Beitrag gibt anhand einer Checkliste Leitlinien zu ihrer Beantwortung. Diese richtet sich seit dem 25.5.2018 bei nicht-öffentlichen Stellen (namentlich Unternehmen, aber auch Vereinen) nach Art. 37 DSGVO und § 38 BDSG n.F.
Die Frage nach der Erforderlichkeit der Benennung eines Datenschutzbeauftragten wird derzeit oft gestellt. Der Beitrag gibt anhand einer Checkliste Leitlinien zu ihrer Beantwortung. Diese richtet sich seit dem 25.5.2018 bei nicht-öffentlichen Stellen (namentlich Unternehmen, aber auch Vereinen) nach Art. 37 DSGVO und § 38 BDSG n.F.
Erfolgsfaktorenforschung
(2018)
Economic growth and ecological problems have pushed industries to switch to eco-friendly technologies. However, environmental impact is still often neglected since production efficiency remains the main concern. Patent analysis in the field of process engineering shows that, on the one hand, some eco-issues appear as secondary problems of the new technologies, and on the other hand, eco-friendly solutions often show lower efficiency or performance capability. The study categorizes typical environmental problems and eco-contradictions in the field of process engineering involving solids handling and identifies underlying inventive principles that have a higher value for environmental innovation. Finally, 42 eco-innovation methods adapting TRIZ are chronologically presented and discussed.
Die Hersteller von Cochlea-Implantat (CI)-Systemen sehen für klinische Audiologen die Möglichkeit vor, die Mikrofonleistung der meisten aktuellen CI-Sprachprozessoren mittels anschließbarer Monitorkopfhörer zu prüfen. Nähere Angaben dazu, nach welchem Prozedere diese Prüfung stattfinden soll, z. B. welche Stimuli mit welchen Pegeln verwendet werden sollen, sind nach Wissen der Autoren seitens der CI-Hersteller nicht verfügbar. Auf der Basis dieser subjektiven Prüfung entscheidet dann der Audiologe, ob der betreffende Sprachprozessor an den Hersteller eingeschickt wird oder nicht. Wir haben eine Messbox entwickelt, mit der die Mikrofonleistung aller abhörbaren CI-Sprachprozessoren der Hersteller Advanced Bionics, Cochlear und MED-EL objektiv geprüft werden kann. Die Box wurde im 3-D-Druckverfahren hergestellt. Der zu prüfende Sprachprozessor wird in die Messbox eingehängt und über einen verbauten Lautsprecher mit definierten Prüfsignalen (Sinustönen unterschiedlicher Frequenz) beschallt. Das Signal des Mikronfons bzw. der Mikrofone wird über das in der Audio-/Abhörbuchse des Prozessors eingesteckte Kabel der Monitorkopfhörer herausgeführt und mit einer Shifting and Scaling-Schaltung in einen Spannungsbereich transformiert, der für die A/D-Wandlung mit einem Mikrokontroller (ATmega1280 verbaut auf einem Arduino Mega) geeignet ist. Derselbe Mikrokontroller übernimmt über einen eigens gebauten D/AWandler die Ausgabe der Prüfsignale über den Lautsprecher. Signalaufnahme und –wiedergabe erfolgt jeweils mit einer Samplingrate von 38,5 kHz. Der frequenzspezifische Effektivwert des abgegriffenen Mikrofonsignals wird mit einem Referenzwert verglichen. Die (frequenzspezifischen) Referenzwerte wurden mit einem neuwertigen Sprachprozessor gleichen Typs ermittelt und im Speicher des Mikrokontrollers abgelegt. Das Ergebnis wird nach Abschluss der Messung grafisch auf einem Touchscreen ausgegeben. Derzeit läuft eine erste Datenerhebung mit in der Klinik subjektiv auffällig gewordenen CI-Sprachprozessoren, die anschließend in der Messbox untersucht werden. Längerfristiges Ziel ist es, die hit und false alarm Raten der subjektiven Prüfung zu ermitteln.
Entscheidungstechniken
(2018)
Entscheidungsfindung: Die Rolle der Kundenemotionen – Was Mimik über Emotion und Entscheidung verrät
(2018)
CONTEXT
The paper addresses the needs of medium and small businesses regarding qualification of R&D specialists in the interdisciplinary cross-industry innovation, which promises a considerable reduction of investments and R&D expenditures. The cross-industry innovation is commonly understood as identification of analogies and transfer of technologies, processes, technical solutions, working principles or business models between industrial sectors. However, engineering graduates and specialists frequently lack the advanced skills and knowledge required to run interdisciplinary innovation across the industry boundaries.
PURPOSE
The study compares the efficiency of the cross-industry innovation methods in one semester project-oriented course. It identifies the individual challenges and preferred working techniques of the students with different prior knowledge, sets of experiences, and cultural contexts, which require attention by engineering educators.
APPROACH
Two parallel one-semester courses were offered to the mechanical and process engineering students enrolled in bachelor’s and master’s degree programs at the faculty of mechanical and process engineering. The students from different years of study were working in 12 teams of 3…6 persons each on different innovation projects, spending two hours a week in the classroom and additionally on average two hours weekly on their project research. Students' feedback and self-assessments concerning gained skills, efficiency of learned tools and intermediate findings were documented, analysed, and discussed regularly along the course.
RESULTS
Analysis of numerous student projects allows to compare and to select the tools most appropriate for finding cross-industry solutions, such as thinking in analogies, web monitoring, function-oriented search, databases of technological effects and processes, special creativity techniques and others. The utilization of learned skills in practical innovation work strengthens the motivation of students and enhances their entrepreneurial competences. Suggested learning course and given recommendations help facilitate sustainable education of ambitious specialists.
CONCLUSIONS
The structured cross-industry innovation can be successfully run as a systematic process and learned in one semester course. The choice of the preferred working teqniques made by the students is affected by their prior knowledge in science, practical experience, and cultural contexts. Major outcomes of the students’ innovation projects such as feasibility, novelty and customer value of the concepts are primarily influenced by students’ engineering design skills, prior knowledge of the technologies, and industrial or business experience.
Deafblindness is a condition that limits communication capabilities primarily to the haptic channel. In the EU-funded project SUITCEYES we design a system which allows haptic and thermal communication via soft interfaces and textiles. Based on user needs and informed by disability studies, we combine elements from smart textiles, sensors, semantic technologies, image processing, face and object recognition, machine learning, affective computing, and gamification. In this work, we present the underlying concepts and the overall design vision of the resulting assistive smart wearable.
The high frequency (HF) catheter ablation is the gold standard for the therapy of many cardiac tachyarrhythmias, such as atrioventricular node re-entry tachycardia (AVNRT), atrioventricular re-entry tachycardia (AVRT) or atrial flutter (AFL). The aim of the study was to simulate the HF ablation of AVNRT, AVRT, AFL and its heat propagation in reference to the supplied power with different electrode material and electrode size. The modeling and simulation were performed with the thermal and electromagnetic simulation software CST® (Computer Simulation Technology, Darmstadt). The modeling and simulation were carried out using ablation catheters with 4 mm tip electrode and 8 mm tip electrode with different electrode materials. Both electrode types were made of platinum and gold respectively. For the measurement of the heat propagation in the heart tissue, the catheters were integrated in the Offenburg heart rhythm model. The HF ablation procedures were performed with the 4 mm platinum tip electrode, with an application duration of 45 seconds and a power output of 40 watts. The HF ablation of the atrioventricular node slow pathway produced a maximum temperature of 66.33 °C. The Kent bundle HF ablation in the left atrium achieved a maximum temperature of 67.14 °C. The HF ablation of the right atrial isthmus resulted 65.96 °C. The 8 mm distal platinum tip electrode and a power output of 60 watts reached 72.85 °C. The 8 mm distal gold tip electrode and a power output of 60 watt reached 64.66 °C, due to the improved thermal conductivity of gold. Virtual heart and ablation electrode models allow the static and dynamic simulation of HF ablation with different electrode material and electrode size. The 3D simulation of the temperature profile may be used to optimize the AVNRT, AVRT and AFL HF ablation.
Cardiac resynchronization therapy (CRT) with hemodynamic optimized biventricular pacing is an established therapy for heart failure patients with sinus rhythm, reduced left ventricular ejection fraction and wide QRS complex. The aim of the study was to evaluate electrical right and left cardiac atrioventricular delay and left atrial delay in CRT responder and non-responder with sinus rhythm.
Methods: Heart failure patients with New York Heart Association class 3.0 ± 0.3, sinus rhythm and 27.7 ± 6.1% left ventricular ejection fraction were measured by surface ECG and transesophageal bipolar left atrial and left ventricular ECG before implantation of CRT devices. Electrical right cardiac atrioventricular delay was measured between onset of P wave and onset of QRS complex in the surface ECG, left cardiac atrioventricular delay between onset of left atrial signal and onset of left ventricular signal in the transesophageal ECG and left atrial delay between onset and offset of left atrial signal in the transesophageal ECG.
Results: Electrical atrioventricular and left atrial delay were 196.9 ± 38.7 ms right and 194.5 ± 44.9 ms left cardiac atrioventricular delay, and 47.7 ± 13.9 ms left atrial delay. There were positive correlation between right and left cardiac atrioventricular delay (r = 0.803 P < 0.001) and negative correlation between left atrial delay and left ventricular ejection fraction (r = −0.694 P = 0.026) with 67% CRT responder.
Conclusions: Transesophageal electrical left cardiac atrioventricular delay and left atrial delay may be useful preoperative atrial desynchronization parameters to improve CRT optimization.
Einleitung
(2018)
Einführender Überblick
(2018)
Existing ultrasonic stress evaluation methods utilize the acoustoelastic effect for bulk waves propagating in volume, which is unsuitable for a surface treated material, possessing a significant variation in material properties with depth. With knowledge of nonlinear elastic parameters – third-order elastic constants (TOEC) close to the surface of the sample, the acoustoelastic effect might be used with surface acoustic waves. This work is focused on the development of an independent method of TOEC measurement using the effect of nonlinear surface acoustic waves scattering – i.e. the effect of elastic waves interaction in a nonlinear medium.
In this paper, the possible three wave interactions of surface guided waves and bulk waves are described and formulae for the efficiency of harmonic generation and mode mixing are derived. A comparison of the efficiency of surface waves scattering in an isotropic medium for different interaction types is carried out with the help of nonlinear perturbation theory. First results for surface and bulk wave mixing with known second- and third-order elastic constants are shown.
Printed Electronics (PE) is a promising technology that provides mechanical flexibility and low-cost fabrication. These features make PE the key enabler for emerging applications, such as smart sensors, wearables, and Internet of Things (IoTs). Since these applications need secure communication and/or authentication, it is vital to utilize security primitives for cryptographic key and identification. Physical Unclonable Functions (PUF) have been adopted widely to provide the secure keys. In this work, we present a weak PUF based on Electrolyte-gated FETs using inorganic inkjet printed electronics. A comprehensive analysis framework including Monte Carlo simulations based on real device measurements is developed to evaluate the proposed PE-PUF. Moreover, a multi-bit PE-PUF design is proposed to optimize area usage. The analysis results show that the PE-PUF has ideal uniqueness, good reliability, and can operates at low voltage which is critical for low-power PE applications. In addition, the proposed multi-bit PE-PUF reduces the area usage around 30%.