767 research outputs found
Joint estimation of channel, range, and doppler for FMCW radar with sparse bayesian learning
No full textApplication of Analog Adaptive Filters for Dynamic Sensor Compensation
No full textThis paper investigates the application of analog adaptive techniques to the area of dynamic sensor compensation, of which there is little reported work in the literature. The case is illustrated by showing how the response of a load cell can be improved to speed up the process of measurement. The load cell is a sensor with an oscillatory output in which the measurand contributes to the response parameters. Thus, a compensation filter needs to track variation in measurand whereas a simple, fixed filter is only valid at one specific load value. To facilitate this investigation, computer models for the load cell and the adaptive compensation filter have been developed. To allow a practical implementation of the adaptive techniques, a novel piecewise linearization technique is proposed in order to vary a floating voltage-controlled resistor in a linear manner over a wide range. Simulation and practical results are presented, thus demonstrating the effectiveness of the proposed techniques
Untersuchung der HF-Übertragungseigenschaften des PropSim Kanalemulators für den WLAN Standard IEEE 802.11p
Get PDFA successful development of wireless systems demands requirements on product development methods and testing. The real-time measurements and performance evaluation of a wireless communication system in different development stages, enable detection of system design errors at the earliest and less expensive stage of the development. The radio channel, as the medium, linking the transmitter to the receiver has an great impact on the wireless system performance. Thus the understanding of the radio channel behavior, is a key factor in developing wireless products. The radio channel characterizations are determined through a measurement campaign and mathematically formulated as a radio channel model. A real-world performance measurement is costly, and because of the unpredictable variations in the interference and stochastic behavior of the wireless propagation channel, specifically in a time-varying system, not reproducible. This motivates the need for a radio frequency platform which reproduces real-world conditions for the wireless system performance evaluation in the laboratory environment. The channel emulator, which replaces the real-world radio channel, is a major component of this testing platform. In this thesis the channel emulator Elektrobit Propsim C2, and the methodology of channel model implementation on it is investigated. Furthermore the vehicular channel models, such as the Six Time- and Frequency-Selective Empirical Channel Models for Vehicular Wireless LANs and the ETSI ITS channel models, which were developed in 2013 [10], are studied. The ETSI ITS channel models contains five Vehicle-to-Vehicle (V2V) scenarios, whereby two of them are without availability of a LOS path. The aim of this study is to understand the channel model parameters, presented in these models, for the further implementation on the EB Propsim C2. There are two options for the implementation of the channel models on the Propsim C2, namely through the Edit sceen in the Graphical User Interface (GUI), or through generating the Impulse Responses (IRs) on the computer, storing the IR-file on the Propsim C2 and run the emulation through this IR-file. Both methods are presented and the restrictions and advantages of each method are described. As mentioned above, the real-world performance evaluation of a wireless communication system is extremely important. The major part of this thesis, is about computing the Packet Error Ratio (PER) of the Kapsch transceiver MTX-9450, which is based on standard IEEE 802.11p in Physical layer (PHY), for the ETSI ITS channel models. For this purpose a measurement plan is developed. The PER graphs are plotted in logarithmic scale over the average received power. The PER measurement is performed for three LOS scenarios and two NLOS scenarios of the ETSI ITS channel models in data rates 3 Mbps, 6 Mbps, and 12 Mbps, which utilize the BPSK and QPSK baseband modulation scheme. The PER measurement in channel models without availability of a LOS path is carried out with the reduced relative speed of the vehicle to about 40 km/h, in order to be able to receive packets through the Propsim C2
Branding the 'Beur' Author Minority Writing and the Media in France
No full textThis book reconsiders authorship by the descendants of North African immigrants to France by consulting how these authors' novels have been discussed and promoted in the national audio-visual media.Cover -- Contents -- Acknowledgements -- List of Illustrations -- 1. Authorship at a Crossroads -- 2. Mehdi Charef and the Invention of Beur Writing -- 3. Competing Visions of Minority Authorship -- 4. Eyewitness Narratives and the Creation of the Beurette -- 5. Rachid Djaïdani and the Shift from Beur to Banlieue Writing -- 6. Revising the Beurette Label -- 7. Sabri Louatah and the Collectif Qui Fait la France? -- Works Cited -- IndexThis book reconsiders authorship by the descendants of North African immigrants to France by consulting how these authors' novels have been discussed and promoted in the national audio-visual media.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
A new, 3D overlapping-sphere model of cell adhesion:
No full textCell adhesion refers to the ability of cells to make enduring and dynamic attachments to extracellular surfaces and to each other; rightly so it is a focal point of current biological research. I have designed a computational framework to model cell adhesion using a modified overlapping-sphere model. A core feature of the model is the three-dimensional representation of a cell surface that can interact mechanically with its environment. The generalization of a cell as a sphere gives our model the compactness to enable the simulations of thousands of cells, comparable to the number of cells typically encountered through small scale studies of early development and disease. Specifically, we use this computational framework to model adhesion between cells in a monolayer and a fibrous environment, cell shape change, as well as cell replication. We also include elements of cell orientation, or cell polarity, and touch on some aspects of mechanical feedback. We explore some general aspects of developmental biology as well as cancer in mammary ducts. Although we emphasize epithelial cells, which are cells that form monolayers, we also briefly consider migratory cells. The major results are that (1) Cells in a monolayer, like sheets and tubes, need to be both mobile and well-connected to adapt to mechanically stresses, (2) Cells that are not polarized do not produce a stable monolayer of cells, (3) Extracellular support, like a basement membrane, can minimize the stresses experienced at cell-cell junctions, (4) Mitosis triggered by tension can help maintain a monolayer of cells, (5) Cell shape needs to be incorporated into models to minimize undesirable stresses, (6) Our computational framework is useful to predict behavior of cells subjected to mechanical forces. As this is a new model, results are chiefly qualitative, and suggest future work in collaboration with experimentalists to verify and quantitate our results.M.S.Includes bibliographical references (p. 79-81)by Mehdi Doum
Positioning with 5G reference signals for vehicular applications
Get PDFModerne sicherheitskritische Fahrzeuganwendungen wie autonomes Fahren oder Advanced Driver Assistance Systems (ADAS) benötigen genaue Information über die Position des Fahrzeuges. Sensorbasierte Positionierungsmethoden wie Global Satellite Navigation Systems (GNSS), Radio/Light Detection and Ranging (RADAR/LiDAR) oder Kamerasysteme sind gut erforscht und können eine hohe Positionsgenauigkeit erreichen, haben aber ihre spezfische Schwächen. Die Positionsgenauigkeit von GNSS verringert sich stark in urbanen Gegenden und RADAR/LiDAR bzw. Kamerasysteme benötigen zur globalen Positionierung dreidimensionale Karten der Umgebung auf Basis von Punktwolken und rechenintensive Algorithmen, nur um einige Nachteile zu nennen. Kooperative, Vehicle-to-Infrastructure (V2I) Positionierung im gerade aufkommenden Mobilfunknetz der 5. Generation (5G-NR) ist ein Technologiekandidat für genaue und verlässliche Fahrzeugpositionierung aufgrund von erhöhter Bandbreite, der Unterstützung des Millimeterwellenbandes (mmWave) und der Verdichtung des Mobilfunknetzes, hat aber bisher nur moderate Aufmerksamkeit der Forschungsgemeinschaft für diese konkrete Anwedung bekommen. In dieser Arbeit untersuchen wir die Positionierung mittels Time Difference of Arrival (TDOA) mit 5G-NR standardkonformen Referenzsignalen. Ein besonderer Fokus liegt hier auf Situationen ohne Sichtverbindung und mit Mehrwegeausbreitung, da diese in (sub-)urbanen Fahrzeugszenarien vorherrschend sind. Zu diesem Zweck präsentieren wir verschiedenen Techniken zur Schätzung von Verzögerungsprofilen und Methoden zur Detektion der Verzögerung des direkten Pfades um eine genaue Schätzung der Signalverzögerung und somit der Entfernung zur ermöglichen. Weiters vergleichen wir die Genauigkeit der Techniken mittels MATLAB-Simulationen. Darauf aufbauend zeigen wir Methoden zur Lösungsapproximation des hyperbolischen Positionierungsproblems, welches als Resultat der TDOA-Messung entsteht. Die Genauigkeit der Methoden wird in Situationen ohne Sichtverbindung und mit Mehrwegeausbreitung mittels Simulationen verglichen. Zum Abschluss fügen wir ein Ende-zu-Ende Positionierungssystem auf Basis der bestgeeigneten Methoden zusammen. Um das System zu evaluieren, konstruieren wir ein Fahrzeugszenario basierend auf der Geometrie in der realen Welt und simulieren die Positionierungsgenauigkeit entlang einer Fahrzeugtrajektorie. Die Resultate bestätigen, dass unser vorgeschlagenes System in der herausfordernden Umgebung des Szenarios genaue Positionisinformation bereitstellen kann.State-of-the-art safety-critical vehicular applications like autonomous driving or advanced driver assistance systems (ADAS) require accurate knowledge of the vehicle position. Sensor-based positioning methods such as global satellite navigation systems (GNSS), radio/light detection and ranging (RADAR/LiDAR) or camera systems are well-studied and can provide high positioning accuracy, but have their specific weaknesses. The performance of GNSS positioning severly degrades in urban environments, while RADAR/LiDAR or camera systems require three-dimensional point cloud maps and computationally expensive algorithms in order to perform global positioning, only to name a few drawbacks. Cooperative, vehicle-to-infrastructure (V2I) positioning in the upcoming 5th generation cellular network (5G-NR) is a candidate technology for accurate and reliable vehicular positioning due to increased bandwidth, support for the millimeter wave band (mmWave) and network densification, but has up until now received less attention from the research community for this particular application. In this work, we investigate time difference of arrival (TDOA) positioning with 5G-NR standard-compliant reference signals, with a strong focus on non line of sight (NLOS) and multipath propagation prevalent in (sub-)urban vehicular scenarios. For this purpose, we introduce various delay profile estimation techniques and direct path delay peak detection methods in order to perform accurate time delay and range estimation and compare their performance with MATLAB simulations. Based on that, we show methods for approximately solving the hyperbolic positioning problem arising from the TDOA measurements and compare their performance based on simulations in NLOS and multipath-heavy situations. Finally, we construct an end-to-end positioning framework comprised of the best-suited methods. In order to evaluate this framework, we build an urban vehicular scenario based on real-world geometry data and simulate the positioning accuracy along a vehicular trajectory. The results confirm that our proposed positioning framework is capable of providing accurate position information in the harsh propagation environment encountered in the simulation scenario
Correction: Synthesis and characterization of a new ZIF-67@MgAl 2 O 4 nanocomposite and its adsorption behaviour
No full textPublisher Copyright: © 2021 The Royal Society of Chemistry.The authors regret that an incorrect affiliation was given for co-author Mehdi Bazarganipour in the original article. The correct affiliations are as shown here. The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers
RETHINKING INDUSTRIAL POLICY
Get PDFDespite the hold of the neoliberal orthodoxy on policy making in developing countries, industrial policy remains important for the promotion of industrial development. However, the context for the design of industrial policy has profoundly changed as a result of new rules governing international trade, the rise of global value chains and marketing networks, and other aspects of globalization. Traditionally, the case for industrial policy has been framed in terms of “market failures” but the paper argues that that is not a sufficient basis. After addressing the traditional points of criticism, an attempt is made to outline the “domains” of industrial policy in the current circumstances, especially for industrially lagging countries. As country contexts differ widely there are no satisfactory blueprints for policy making that countries can readily adopt. As in production decisions, considerable ingenuity and innovation is needed in designing policies. This is all the more necessary as the WTO rules have become increasingly stringent and the rise of international trading networks has created new barriers for young firms to enter the world market. These developments have changed the context but not the importance of policy in industrial development. The paper identifies areas where government intervention is needed and can still make a positive difference.
Higher education in Oregon's prisons: measures of access, equity and excellence in practice
No full textresearch team: Maya Lazaro, Jove Rousseau, Fatima Mehdi, James Conway.Title from PDF cover (viewed on November 3, 2021)."2021 Masters of Public Administration Capstone Research."This archived document is maintained by the State Library of Oregon as part of the Oregon Documents Depository Program. It is for informational purposes and may not be suitable for legal purposes.Includes bibliographical references (pages 30-32).Mode of access: Internet from the Oregon Government Publications Collection.Text in English
Application of the extended discrete element method (XDEM) in the melting of a single particle
No full textIn this contribution, a new method referred to as Extended Discrete Element Method (XDEM) is usedto model melting of a single particle in the fluid media. The XDEM as a Lagrangian-Eulerian framework is the extension of Discrete Element Method (DEM) by considering thermodynamic state such as temperature distribution and is able to link with Computational Fluid Dynamics (CFD) for fluid phase. In order to provide more accurate results, multiscale method was used. The model is validated by comparing predicted results with existing experimental data for melting of a single ice particle in a water bath. In addition, the model has the capability to be extended to the packed bed of particles with different size and properties to produce different liquid phases
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