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In order to maximize the possible travel distance of battery electric vehicles with one battery charge, it is mandatory to adjust all components of the powertrain carefully to each other. While current vehicle designs mostly simplify the powertrain rigorously and use an electric motor in combination with a gearbox with only one fixed transmission ratio, the use of multi-gear systems has great potential. First, a multi-speed system is able to improve the overall energy efficiency. Secondly, it is able to reduce the maximum momentum and therefore to reduce the maximum current provided by the traction battery, which results in a longer battery lifetime. In this paper, we present a systematic way to generate multi-gear gearbox designs that—combined with a certain electric motor—lead to the most efficient fulfillment of predefined load scenarios and are at the same time robust to uncertainties in the load. Therefore, we model the electric motor and the gearbox within a Mixed-Integer Nonlinear Program, and optimize the efficiency of the mechanical parts of the powertrain. By combining this mathematical optimization program with an unsupervised machine learning algorithm, we are able to derive global-optimal gearbox designs for practically relevant momentum and speed requirements.
Es wird von Gleichungen ausgegangen, mit denen die Modellkoeffizienten von Regelstrecken mit Ausgleich aus der gemessenen Sprungantwort ermittelt werden können. Die Übertragungsfunktion der Regelstrecke hat einen konstanten Zähler und ein Nennerpolynom. Unter der Annahme, daß die ideale und exakte Sprungantwort des Systems durch ein stochastisches Signal gestört wird, wird untersucht, wie die Fehler der ermittelten Modellkoeffizienten von Kennwerten des Störsignals und von der Meßzeit für die Sprungantwort abhängen. Durch eine Simulation auf dem Digitalrechner wurden die Ergebnisse kontrolliert. Es zeigt sich, daß durch eine Filterung der gestörten Sprungantwort über einen Tiefpaß keine Verbesserung der Analyseergebnisse erreicht werden kann, da das Identifizierungsverfahren eine glättende Eigenschaft hat.
Purpose
To demonstrate that high quality T₂-weighted (T2w) turbo spin-echo (TSE) imaging of the complete prostate can be achieved routinely and within safety limits at 7 T, using an external transceive body array coil only.
Methods
Nine healthy volunteers and 12 prostate cancer patients were scanned on a 7 T whole-body system. Preparation consisted of B₀ and radiofrequency shimming and localized flip angle calibration. T₁ and T₂ relaxation times were measured and used to define the T2w-TSE protocol. T2w imaging was performed using a TSE sequence (pulse repetition time/echo time 3000–3640/71 ms) with prolonged excitation and refocusing pulses to reduce specific absorption rate.
Results
High quality T2w TSE imaging was performed in less than 2 min in all subjects. Tumors of patients with gold-standard tumor localization (MR-guided biopsy or prostatectomy) were well visualized on 7 T imaging (n = 3). The number of consecutive slices achievable within a 10-g averaged specific absorption rate limit of 10 W/kg was ≥28 in all subjects, sufficient for full prostate coverage with 3-mm slices in at least one direction.
Conclusion
High quality T2w TSE prostate imaging can be performed routinely and within specific absorption rate limits at 7 T with an external transceive body array.
Purpose
To assess potential cognitive deficits under the influence of static magnetic fields at various field strengths some studies already exist. These studies were not focused on attention as the most vulnerable cognitive function. Additionally, mostly no magnetic resonance imaging (MRI) sequences were performed.
Materials and Methods
In all, 25 right-handed men were enrolled in this study. All subjects underwent one MRI examination of 63 minutes at 1.5 T and one at 7 T within an interval of 10 to 30 days. The order of the examinations was randomized. Subjects were referred to six standardized neuropsychological tests strictly focused on attention immediately before and after each MRI examination. Differences in neuropsychological variables between the timepoints before and after each MRI examination were assessed and P-values were calculated
Results
Only six subtests revealed significant differences between pre- and post-MRI. In these tests the subjects achieved better results in post-MRI testing than in pre-MRI testing (P = 0.013–0.032). The other tests revealed no significant results.
Conclusion
The improvement in post-MRI testing is only explicable as a result of learning effects. MRI examinations, even in ultrahigh-field scanners, do not seem to have any persisting influence on the attention networks of human cognition immediately after exposure.
Planning the layout and operation of a technical system is a common task
for an engineer. Typically, the workflow is divided into consecutive stages: First,
the engineer designs the layout of the system, with the help of his experience or of
heuristic methods. Secondly, he finds a control strategy which is often optimized
by simulation. This usually results in a good operating of an unquestioned sys-
tem topology. In contrast, we apply Operations Research (OR) methods to find a
cost-optimal solution for both stages simultaneously via mixed integer program-
ming (MILP). Technical Operations Research (TOR) allows one to find a provable
global optimal solution within the model formulation. However, the modeling error
due to the abstraction of physical reality remains unknown. We address this ubiq-
uitous problem of OR methods by comparing our computational results with mea-
surements in a test rig. For a practical test case we compute a topology and control
strategy via MILP and verify that the objectives are met up to a deviation of 8.7%.
The conference center darmstadtium in Darmstadt is a prominent example of energy efficient buildings. Its heating system consists of different source and consumer circuits connected by a Zortström reservoir. Our goal was to reduce the energy costs of the system as much as possible. Therefore, we analyzed its supply circuits. The first step towards optimization is a complete examination of the system: 1) Compilation of an object list for the system, 2) collection of the characteristic curves of the components, and 3) measurement of the load profiles of the heat and volume-flow demand. Instead of modifying the system manually and testing the solution by simulation, the second step was the creation of a global optimization program. The objective was to minimize the total energy costs for one year. We compare two different topologies and show opportunities for significant savings.
Ground or aerial robots equipped with advanced sensing technologies, such as three-dimensional laser scanners and advanced mapping algorithms, are deemed useful as a supporting technology for first responders. A great deal of excellent research in the field exists, but practical applications at real disaster sites are scarce. Many projects concentrate on equipping robots with advanced capabilities, such as autonomous exploration or object manipulation. In spite of this, realistic application areas for such robots are limited to teleoperated reconnaissance or search. In this paper, we investigate how well state-of-the-art and off-the-shelf components and algorithms are suited for reconnaissance in current disaster-relief scenarios. The basic idea is to make use of some of the most common sensors and deploy some widely used algorithms in a disaster situation, and to evaluate how well the components work for these scenarios. We acquired the sensor data from two field experiments, one from a disaster-relief operation in a motorway tunnel, and one from a mapping experiment in a partly closed down motorway tunnel. Based on these data, which we make publicly available, we evaluate state-of-the-art and off-the-shelf mapping approaches. In our analysis, we integrate opinions and replies from first responders as well as from some algorithm developers on the usefulness of the data and the limitations of the deployed approaches, respectively. We discuss the lessons we learned during the two missions. These lessons are interesting for the community working in similar areas of urban search and rescue, particularly reconnaissance and search.
Mechatronics consist of the integration of mechanical
engineering, electronic integration and computer science/
engineering. These broad fields are essential for robotic
systems, yet it makes it difficult for the researchers to specialize
and be experts in all these fields. Collaboration between
researchers allow for the integration of experience and specialization,
to allow optimized systems. Collaboration between the
European countries and South Africa is critical, as each country
has different resources available, which the other countries
might not have. Applications with the need for approval of
any restrictions, can also be obtained easier in some countries
compared to others, thus preventing the delays of research.
Some problems that have been experienced are discussed, with
the Robotics Center of South Africa as a possible solution.
Because of customer churn, strong competition, and operational inefficiencies, the telecommunications operator ME Telco (fictitious name due to confidentiality) launched a strategic transformation program that included a Business Process Management (BPM) project. Major problems were silo-oriented process management and missing cross-functional transparency. Process improvements were not consistently planned and aligned with corporate targets. Measurable inefficiencies were observed on an operational level, e.g., high lead times and reassignment rates of the incident management process.
Das von Texas-Instruments (TI) vertriebene Interface CBL2 wird über einige TI-Grafik-Rechner (TI-92, TI-89 usw.) angesteuert. Wegen seiner Handlichkeit wird dieses System beim Unterricht in wechselnden Räumen »großen« Messwerterfassungssystemen oft vorgezogen. Das CBL2 bietet drei analoge Eingänge, die immerhin mit 10 Bit Auflösung und bis zu einer Frequenz von 50 kHz arbeiten. Weiterhin besitzt das CBL2 eine Buchse für angeblich nur einen digitalen Ein- bzw. Ausgang. An diesem Eingang wird standardmäßig hauptsächlich der Bewegungssensor CBR betrieben. In diesem Beitrag werden Erweiterungsmöglichkeiten dieses Anschlusses beschrieben.
Kritische Infrastrukturen sind primäre Ziele krimineller Hacker. Der Deutsche Bundestag reagierte darauf am 25. Juli 2015 mit einem Gesetz zur Verbesserung der Sicherheit von ITSystemen, dem IT-Sicherheitsgesetz. Dies verlangt von Betreibern kritischer Infrastrukturen, angemessene Mindeststandards für organisatorische und technische Sicherheit zu implementieren, um den Betrieb und die Verfügbarkeit dieser Infrastruktur zu gewährleisten. Telekommunikationsunternehmen sind einerseits von diesem Gesetz in besonderem Maße betroffen und verfügen andererseits mit dem Rahmenwerk enhanced Telecom Operations Map (eTOM) über ein international anerkanntes Referenzmodell zur Gestaltung von Geschäftsprozessen in dieser Branche. Da sämtliche Telekommunikationsunternehmen in Deutschland verpflichtet sind, das Gesetz innerhalb eines bestimmten Zeitrahmens zu implementieren, präsentiert dieser Beitrag einen Vorschlag zur Erweiterung von eTOM um die relevanten Anforderungen des deutschen IT-Sicherheitsgesetzes.
In this work, we report on our attempt to design and implement an early introduction to basic robotics principles for children at kindergarten age. One of the main challenges of this effort is to explain complex robotics contents in a way that pre-school children could follow the basic principles and ideas using examples from their world of experience. What sets apart our effort from other work is that part of the lecturing is actually done by a robot itself and that a quiz at the end of the lesson is done using robots as well. The humanoid robot Pepper from Softbank, which is a great platform for human–robot interaction experiments, was used to present a lecture on robotics by reading out the contents to the children making use of its speech synthesis capability. A quiz in a Runaround-game-show style after the lecture activated the children to recap the contents they acquired about how mobile robots work in principle. In this quiz, two LEGO Mindstorm EV3 robots were used to implement a strongly interactive scenario. Besides the thrill of being exposed to a mobile robot that would also react to the children, they were very excited and at the same time very concentrated. We got very positive feedback from the children as well as from their educators. To the best of our knowledge, this is one of only few attempts to use a robot like Pepper not as a tele-teaching tool, but as the teacher itself in order to engage pre-school children with complex robotics contents.
Erfolgreiches IT-Marketing
(2013)
In diesem Paper wird die Entwicklung und Evaluation eines grafischen Regeleditors für das Erstellen von „Smart Living Environments“-Services vorgestellt. Dafür werden zunächst die Deduktion und Implementierung des grafischen Regeleditors erläutert. Anschließend wird eine Probandenstudie vorgestellt, in welcher der Mehrwert bezogen auf die Aspekte Zeit, Fehleranfälligkeit und Gebrauchstauglichkeit festgestellt wird.
Obwohl es eine Vielzahl von Einführungskonzepten für ITSM gibt, hat sich bisher keines dieser Konzepte auf breiter Linie durchgesetzt. Das gilt in erhöhtem Maße für ITSM-Einführungskonzepte für KMU, wohl nicht zuletzt aufgrund der Tatsache, dass der Mehrwert von ITSM für KMU aufgrund der geringeren Größe der IT-Organisationen nur entsprechend schwieriger generiert werden kann.
Mit diesem Beitrag wird ein Einführungskonzept für ITSM in KMU systematisch hergeleitet. Dafür wurden zunächst die Treiber und Barrieren von ITSM untersucht, um daraus ein umfassendes Wirkmodell zu entwickeln. Da mit diesem Wirkungsmodell die Einflussfaktoren auf den Erfolg von ITSM in KMU deutlich werden, konnte auf dieser Basis ein Einführungskonzept abgeleitet werden, welches insbesondere die positiven Effekte unterstützt bzw.
verstärkt.
Die Telekommunikationsindustrie hat in den letzten Jahrzehnten einen enormen Wandel vollzogen. Für Telekommunikationsunternehmen erfordert dies fundamentale Umstrukturierungen von Strategie, Prozessen, Anwendungssystemen und Netzwerktechnologien. Dabei spielen Unternehmensarchitekturen und Referenzmodelle eine wichtige Rolle. Zwar existieren in der Praxis anerkannte Referenzmodelle, aber wie sind diese für eine systematische Transformation zu gestalten? Wie sieht eine konkrete Lösung für die Telekommunikationsindustrie aus?
Als Antwort stellt Christian Czarnecki in seinem Buch eine referenzmodellbasierte Unternehmensarchitektur vor. Basierend auf einer umfangreichen Untersuchung von Transformationsprojekten werden Probleme und Anforderungen der Praxis identifiziert, für die mit Methoden der Unternehmenstransformation, Referenzmodellierung und Unternehmensarchitektur ein Lösungsvorschlag entwickelt und evaluiert wird. Dieser besteht u. a. aus detaillierten Anwendungsfällen, Referenzprozessabläufen, einer Zuordnung von Prozessen zu Anwendungssystemen sowie Handlungsempfehlungen zur Virtualisierung.
Für Wissenschaftler und Studierende der Wirtschaftsinformatik zeigt das Buch neue Erkenntnisse einer anwendungsorientierten Referenzmodellierung. Für Praktiker liefert es eine methodisch fundierte Lösung für die aktuellen Transformationsbedarfe der Telekommunikationsindustrie. Christian Czarnecki arbeitet seit 2004 als Unternehmensberater und hat viele Telekommunikationsunternehmen bei deren Transformation begleitet. In 2013 erfolgte die Promotion zum Doktoringenieur an der Otto-von-Guericke-Universität Magdeburg.