Global ETD Search

791	High Performance RF and Basdband Analog-to-Digital Interface for Multi-standard/Wideband Applications Zhang, Heng 2010 December 1900 (has links) The prevalence of wireless standards and the introduction of dynamic standards/applications, such as software-defined radio, necessitate the next generation wireless devices that integrate multiple standards in a single chip-set to support a variety of services. To reduce the cost and area of such multi-standard handheld devices, reconfigurability is desirable, and the hardware should be shared/reused as much as possible. This research proposes several novel circuit topologies that can meet various specifications with minimum cost, which are suited for multi-standard applications. This doctoral study has two separate contributions: 1. The low noise amplifier (LNA) for the RF front-end; and 2. The analog-to-digital converter (ADC). The first part of this dissertation focuses on LNA noise reduction and linearization techniques where two novel LNAs are designed, taped out, and measured. The first LNA, implemented in TSMC (Taiwan Semiconductor Manufacturing Company) 0.35Cm CMOS (Complementary metal-oxide-semiconductor) process, strategically combined an inductor connected at the gate of the cascode transistor and the capacitive cross-coupling to reduce the noise and nonlinearity contributions of the cascode transistors. The proposed technique reduces LNA NF by 0.35 dB at 2.2 GHz and increases its IIP3 and voltage gain by 2.35 dBm and 2dB respectively, without a compromise on power consumption. The second LNA, implemented in UMC (United Microelectronics Corporation) 0.13Cm CMOS process, features a practical linearization technique for high-frequency wideband applications using an active nonlinear resistor, which obtains a robust linearity improvement over process and temperature variations. The proposed linearization method is experimentally demonstrated to improve the IIP3 by 3.5 to 9 dB over a 2.5–10 GHz frequency range. A comparison of measurement results with the prior published state-of-art Ultra-Wideband (UWB) LNAs shows that the proposed linearized UWB LNA achieves excellent linearity with much less power than previously published works. The second part of this dissertation developed a reconfigurable ADC for multistandard receiver and video processors. Typical ADCs are power optimized for only one operating speed, while a reconfigurable ADC can scale its power at different speeds, enabling minimal power consumption over a broad range of sampling rates. A novel ADC architecture is proposed for programming the sampling rate with constant biasing current and single clock. The ADC was designed and fabricated using UMC 90nm CMOS process and featured good power scalability and simplified system design. The programmable speed range covers all the video formats and most of the wireless communication standards, while achieving comparable Figure-of-Merit with customized ADCs at each performance node. Since bias current is kept constant, the reconfigurable ADC is more robust and reliable than the previous published works. High frequency linearization single-stage ultrawideband(UWB) low noise amplifier (LNA) common gate (CG) low power RF capacitive cross-coupling noise figure noise reduction linearity improvement linearity linearization IIP2 IIP3 1dB compression point distortion cancelling broadband LNA CMOS technology scaling design guidelines ADC pipeline ADC cyclic ADC SAR ADC time-to-digital converter video application multi-standard receiver analog power scaling reconfigurable programmable scalable adaptive
792	Malleability, obliviousness and aspects for broadcast service attachment Harrison, William January 2010 (has links) An important characteristic of Service-Oriented Architectures is that clients do not depend on the service implementation's internal assignment of methods to objects. It is perhaps the most important technical characteristic that differentiates them from more common object-oriented solutions. This characteristic makes clients and services malleable, allowing them to be rearranged at run-time as circumstances change. That improvement in malleability is impaired by requiring clients to direct service requests to particular services. Ideally, the clients are totally oblivious to the service structure, as they are to aspect structure in aspect-oriented software. Removing knowledge of a method implementation's location, whether in object or service, requires re-defining the boundary line between programming language and middleware, making clearer specification of dependence on protocols, and bringing the transaction-like concept of failure scopes into language semantics as well. This paper explores consequences and advantages of a transition from object-request brokering to service-request brokering, including the potential to improve our ability to write more parallel software. service-oriented aspect-oriented programming language middleware concurrency Data processing Computer science Software Architectures (NEW) Data abstraction (NEW) Domain-specific architectures (NEW) Information hiding (NEW) Language Constructs and Features (E.2) Abstract data types Classes and objects (NEW) Concurrent programming structures Constraints (NEW) Control structures Coroutines Data types and structures Dynamic storage management Frameworks (NEW) Inheritance (NEW) Input/output Modules, packages Patterns (NEW) Polymorphism (NEW) Procedures, functions, and subroutines Recursion
793	Wissensgestütztes Beobachtungs- und Evaluierungssystem der Landnutzung / Bewertung des Erhaltungszustandes des Ökosystems im Einflussbereich einer Gaspipeline in Bolivien / Knowledge-Based Monitoring and Evaluation System of Land Use / Assessing the Ecosystem Conservation Status in the Influence Area of a Gas Pipeline in Bolivia Gorrín Manzuli, Arnélida 07 November 2005 (has links) No description available. 550 Geowissenschaften Mathematics and Computer Science Wissensgestütze Modelle Landnutzungsindikatoren Indirente Auswirkungen von Gaspipelines Erhaltungszustand von Wäldern Bolivien Land use Monitoring and Evaluation Knowledge-based models Land use indicators Gas pipeline indirect impact Forest conservation status Bolivia 74.48 74.03 43.70 43.99 74.26 QGX 544: Bolivien {Geographie}
794	Control of transmission system power flows Kreikebaum, Frank Karl 13 January 2014 (has links) Power flow (PF) control can increase the utilization of the transmission system and connect lower cost generation with load. While PF controllers have demonstrated the ability to realize dynamic PF control for more than 25 years, PF control has been sparsely implemented. This research re-examines PF control in light of the recent development of fractionally-rated PF controllers and the incremental power flow (IPF) control concept. IPF control is the transfer of an incremental quantity of power from a specified source bus to specified destination bus along a specified path without influencing power flows on circuits outside of the path. The objectives of the research are to develop power system operation and planning methods compatible with IPF control, test the technical viability of IPF control, develop transmission planning frameworks leveraging PF and IPF control, develop power system operation and planning tools compatible with PF control, and quantify the impacts of PF and IPF control on multi-decade transmission planning. The results suggest that planning and operation of the power system are feasible with PF controllers and may lead to cost savings. The proposed planning frameworks may incent transmission investment and be compatible with the existing transmission planning process. If the results of the planning tool demonstration scale to the national level, the annual savings in electricity expenditures would be $13 billion per year (2010$). The proposed incremental packetized energy concept may facilitate a reduction in the environmental impact of energy consumption and lead to additional cost savings. Power flow control Transmission planning Power flow controller Controllable network transformer Distributed series reactance Fractionally-rated back-to-back Genetic algorithm Incremental power flow Merchant electrical pipeline Power purchase option Phase-shifting transformer Renewable portfolio standard Security-constrained optimal power flow Static synchronous series compensator Thyristor controlled series capacitor Optimal power flow CNT DSR CSCOPF FR-BTB GA IPF MEP PPO PSCOPF PST RPS SCOPF SSSC TCSC OPF Electric power distribution
795	Calcul flottant haute performance sur circuits reconfigurables Pasca, Bogdan Mihai 21 September 2011 (has links) (PDF) De plus en plus de constructeurs proposent des accélérateurs de calculs à base de circuits reconfigurables FPGA, cette technologie présentant bien plus de souplesse que le microprocesseur. Valoriser cette flexibilité dans le domaine de l'accélération de calcul flottant en utilisant les langages de description de circuits classiques (VHDL ou Verilog) reste toutefois très difficile, voire impossible parfois. Cette thèse a contribué au développement du logiciel FloPoCo, qui offre aux utilisateurs familiers avec VHDL un cadre C++ de description d'opérateurs arithmétiques génériques adapté au calcul reconfigurable. Ce cadre distingue explicitement la fonctionnalité combinatoire d'un opérateur, et la problématique de son pipeline pour une précision, une fréquence et un FPGA cible donnés. Afin de pouvoir utiliser FloPoCo pour concevoir des opérateurs haute performance en virgule flottante, il a fallu d'abord concevoir des blocs de bases optimisés. Nous avons d'abord développé des additionneurs pipelinés autour des lignes de propagation de retenue rapides, puis, à l'aide de techniques de pavages, nous avons conçu de gros multiplieurs, possiblement tronqués, utilisant des petits multiplieurs. L'évaluation de fonctions élémentaires en flottant implique souvent l'évaluation en virgule fixe d'une fonction. Nous présentons un opérateur générique de FloPoCo qui prend en entrée l'expression de la fonction à évaluer, avec ses précisions d'entrée et de sortie, et construit un évaluateur polynomial optimisé de cette fonction. Ce bloc de base a permis de développer des opérateurs en virgule flottante pour la racine carrée et l'exponentielle qui améliorent considérablement l'état de l'art. Nous avons aussi travaillé sur des techniques de compilation avancée pour adapter l'exécution d'un code C aux pipelines flexibles de nos opérateurs. FloPoCo a pu ainsi être utilisé pour implanter sur FPGA des applications complètes. FPGA Virgule flottante FloPoCo Chemin de données arithmétique Pipeline pour une fréquence donnée Addition pipelinée Additionneur rapide Multiplication Karatsuba-Offman Carré Multiplieur tronqué Multiplication par pavage Virgule fixe Approximation polynomiale Racine carrée flottante Exponentielle flottante Accumulation flottante Schéma d'évaluation de Horner Somme de carrés flottante Synthèse de haut niveau Nid de boucles parfait Multiplication de matrices Jacobi Dilemme du fabricant de table Méthode des différences tabulées Communications pipelinées
796	A Physically Based Pipeline for Real-Time Simulation and Rendering of Realistic Fire and Smoke / En fysiskt baserad rörledning för realtidssimulering och rendering av realistisk eld och rök He, Yiyang January 2018 (has links) With the rapidly growing computational power of modern computers, physically based rendering has found its way into real world applications. Real-time simulations and renderings of fire and smoke had become one major research interest in modern video game industry, and will continue being one important research direction in computer graphics. To visually recreate realistic dynamic fire and smoke is a complicated problem. Furthermore, to solve the problem requires knowledge from various areas, ranged from computer graphics and image processing to computational physics and chemistry. Even though most of the areas are well-studied separately, when combined, new challenges will emerge. This thesis focuses on three aspects of the problem, dynamic, real-time and realism, to propose a solution in form of a GPGPU pipeline, along with its implementation. Three main areas with application in the problem are discussed in detail: fluid simulation, volumetric radiance estimation and volumetric rendering. The weights are laid upon the first two areas. The results are evaluated around the three aspects, with graphical demonstrations and performance measurements. Uniform grids are used with Finite Difference (FD) discretization scheme to simplify the computation. FD schemes are easy to implement in parallel, especially with ComputeShader, which is well supported in Unity engine. The whole implementation can easily be integrated into any real-world applications in Unity or other game engines that support DirectX 11 or higher. Visualization Physically Based Pipeline Real-Time Dynamic Simulation Combustion Fire Explosion Smoke Thick Smoke Computer Graphics PDE Numerical Methods Grid Based Navier-Stokes Equation Imcompressible Fluid Radiative Transfer Equation RTE Volumetric Illumination Volumetric Rendering Volumetric Global Illumination Distant Light Source Volumetric Global Shadow Local Shadow Approximation Black-body Radiation Poisson Solver Spectroscopy Fire Color Color Reproduction Tone Mapping Color Temperature Color Matching Function Tristimulus CIE Standard Observer Color Space XYZ RGB GPU GPGPU ComputeShader DirectX 12 Unity C# Computer Sciences Datavetenskap (datalogi)
797	Řešení dopravy v centru Havlíčkova Brodu / Traffic situation in the city centre of Havlíčkův Brod and its solution Tobek, Miroslav January 2013 (has links) The aim of this diploma thesis is the solution of the traffic situation in the city center of Havlíčkův Brod. Mainly the ground road number II/150 adjustment, which consist in the modification of the two-way traffic to one-way traffic organization in the streets Dolní, Žižkova and Na Ostrově by using the analogy of a roundabout layout, is solved within this thesis. All mentioned modifications simplify the traffic situation, improve the orientation and increase the security and the traffic flow mainly in relation to pedestrians and cyclists. Another part of this thesis is focused on revitalization of the public spaces in front of the community center called Ostrov and junction of existing cycle tracks situated on the both banks of the Sázava river. In relation to this topic the adjustment of rainwater sewerage system, low-voltage above ground network, public lighting, communication electric cables, fire brigade signal lights and low-pressure gas pipeline is also solved.
798	A deep learning based anomaly detection pipeline for battery fleets Khongbantabam, Nabakumar Singh January 2021 (has links) This thesis proposes a deep learning anomaly detection pipeline to detect possible anomalies during the operation of a fleet of batteries and presents its development and evaluation. The pipeline employs sensors that connect to each battery in the fleet to remotely collect real-time measurements of their operating characteristics, such as voltage, current, and temperature. The deep learning based time-series anomaly detection model was developed using Variational Autoencoder (VAE) architecture that utilizes either Long Short-Term Memory (LSTM) or, its cousin, Gated Recurrent Unit (GRU) as the encoder and the decoder networks (LSTMVAE and GRUVAE). Both variants were evaluated against three well-known conventional anomaly detection algorithms Isolation Nearest Neighbour (iNNE), Isolation Forest (iForest), and kth Nearest Neighbour (k-NN) algorithms. All five models were trained using two variations in the training dataset (full-year dataset and partial recent dataset), producing a total of 10 different model variants. The models were trained using the unsupervised method and the results were evaluated using a test dataset consisting of a few known anomaly days in the past operation of the customer’s battery fleet. The results demonstrated that k-NN and GRUVAE performed close to each other, outperforming the rest of the models with a notable margin. LSTMVAE and iForest performed moderately, while the iNNE and iForest variant trained with the full dataset, performed the worst in the evaluation. A general observation also reveals that limiting the training dataset to only a recent period produces better results nearly consistently across all models. / Detta examensarbete föreslår en pipeline för djupinlärning av avvikelser för att upptäcka möjliga anomalier under driften av en flotta av batterier och presenterar dess utveckling och utvärdering. Rörledningen använder sensorer som ansluter till varje batteri i flottan för att på distans samla in realtidsmätningar av deras driftsegenskaper, såsom spänning, ström och temperatur. Den djupinlärningsbaserade tidsserieanomalidetekteringsmodellen utvecklades med VAE-arkitektur som använder antingen LSTM eller, dess kusin, GRU som kodare och avkodarnätverk (LSTMVAE och GRU) VAE). Båda varianterna utvärderades mot tre välkända konventionella anomalidetekteringsalgoritmer -iNNE, iForest och k-NN algoritmer. Alla fem modellerna tränades med hjälp av två varianter av träningsdatauppsättningen (helårsdatauppsättning och delvis färsk datauppsättning), vilket producerade totalt 10 olika modellvarianter. Modellerna tränades med den oövervakade metoden och resultaten utvärderades med hjälp av en testdatauppsättning bestående av några kända anomalidagar under tidigare drift av kundens batteriflotta. Resultaten visade att k-NN och GRUVAE presterade nära varandra och överträffade resten av modellerna med en anmärkningsvärd marginal. LSTMVAE och iForest presterade måttligt, medan varianten iNNE och iForest tränade med hela datasetet presterade sämst i utvärderingen. En allmän observation avslöjar också att en begränsning av träningsdatauppsättningen till endast en ny period ger bättre resultat nästan konsekvent över alla modeller. Forklift batteries Battery sensors Data pipeline Predictive maintenance Anomaly detection Deep learning Battery failure prediction Time-series Variational autoencoder Long short-term memory LSTM Gated recurrent unit GRU Isolation nearest neighbor iNNE Isolation forest iForest kth nearest neighbor kNN. Gaffeltruckbatterier Batterisensorer Datapipeline Prediktivt underhåll Avvikelsedetektering Deep learning Batterifelsprediktion Tidsserier Variationsautokodare Långt korttidsminne LSTM Gated recurrent unit GRU Isolation närmaste granne iNNE Isolation skog iForest kth närmaste granne kNN. Computer and Information Sciences Data- och informationsvetenskap
799	Stavebně technologický projekt tepelného napaječe v Jižních Čechách / Construction Technological Project of a Heat Feeder in South Bohemia Handlíř, Jan Unknown Date (has links) The subject of the diploma thesis is a technological construction project of heat feeder on the hot water pipeline between České Budějovice and nuclear power plant Temelín. The main object is an industrial hall made of steel and brick administrative part. The hall is a steel structure clad with sandwich panels. The administrative part is single-storey building from bricks and has a flat roof. The construction also includes an access road with car park.
800	Návrh AD převodníku pro senzorové aplikace / Design of an AD converter for sensor applications Bečková, Zuzana January 2016 (has links) Diplomová práce obsahuje stručný teoretický základ pro designéra/ku A/D převodníku v technologii CMOS a přehled architektur A/D převodníků používaných v automobilovém průmyslu. Volba vhodné architektury pro konkrétní aplikaci byla zásadním úkolem zpra- covaným v semestrálním projektu předcházejícím tuto práci a je rovněž součástí této práce. Analýza v Matlabu, ze které by mělo vyplynout, je-li třeba zahrnout do architek- tury podblok Sample and Hold, je také součástí práce. Klíčovou částí práce je dokumen- tace návrhu jednotlivých podbloků A/D převodníku – operačního zesilovače, kompará- toru a R-2R D/A převodníku – a ověření jejich funkčnosti. V závěru práce je ověřena funkčnost A/D převodníku jako celku.

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