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Aktivní protéza dolní končetiny / Leg prothesisBulva, Ondřej January 2017 (has links)
This thesis deals with the current state of development of active lower limb prostheses and focuses mainly on own design of active prostheses. The introduction deals with the anatomy of lower limb and briefly describes the walk cycle. In other chapters are summarized amputation techniques in the lower limb, followed by a description of the allocation of prostheses according to the level of amputation, which were described in earlier chapters. The thesis also deals with the division of prostheses according to the patient's activity level and briefly describes the structural differences in these individual cases. Chapter describing the actual development in the field of active prostheses initiates part dealing with the detailed description of the part of the prosthesis. The following chapters deal with the design and implementation of a prototype of active transfemoral prosthesis. The penultimate chapter deals with the software description of all parts of the prosthesis. This chapter is followed by an evaluation of the achieved results.
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Analýza zvukové interpretace hudby metodami číslicového zpracování signálu / Analysis of Expressive Music Performance using Digital Signal Processing MethodsFančal, Petr January 2017 (has links)
The aim of this master's thesis is the analysis of musical compositions from the standpoint of time resources of music. The introduction briefly describes the basic musicological terms and variables that are in direct relationship to the time resources in expressive music performance. The following part of the work is devoted to the known methods of digital signal processing, suitable for music information retrieval from audio recordings. In the practical part these methods are demonstrated on three recordings in MATLAB environment and the results were compared in terms of used agogics.
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Structure des noyaux les plus lourds : spectroscopie du noyau ²⁵¹Fm et développement pour des traitements numériques du signal / Structure of the heaviest nuclei : spectroscopy of ²⁵¹Fm and digital signal processing developmentRezynkina, Kseniia 21 September 2016 (has links)
L'un des principaux défis de la physique nucléaire moderne est de comprendre la structure nucléaire des éléments les plus lourds. Les barrières de fission calculées dans le modèle de la goutte liquide macroscopique ne parviennent pas à expliquer la stabilité des noyaux avec un nombre de protons Z≥90. Cette barrière disparaît pour les éléments transfermium (Z≥100) qui ne sont donc stabilisés que par des effets quantiques de couche. Les noyaux lourds sont un laboratoire unique pour étudier l'évolution de la structure nucléaire dans des conditions extrêmes de masse et de champ Coulombien. Bien que de nombreuses théories s’accordent sur l'existence d’un « îlot de stabilité », les prédictions sur son emplacement exact en terme de nombre de protons et neutrons varient grandement. Les études expérimentales des noyaux transfermium s’avèrent donc essentielles pour contraindre les modèles théoriques et mieux comprendre l’évolution des couches nucléaires.L'interaction entre le mouvement des particules individuelles et les degrés de liberté collectifs du noyau a été investiguée dans le 251Fm par le biais de la spectroscopie combinée délectrons de conversion interne et de photons γ. Les états excités du 251Fm ont été peuplés dans la décroissance α du 255No, produit dans les 2 réactions suivantes: 208Pb(48Ca, 1n)255No et 209Bi(48Ca, 2n)255Lr. Les expériences ont été réalisées au JINR, FLNR, Dubna. Les faisceaux intenses ont été délivrés par le cyclotron U-400, et les séparateurs VASSILISSA ou SHELS ont été utilisés pour sélectionner les résidus de fusion-évaporation. Le spectromètre GABRIELA a été utilisé pour effectuer des mesures des propriétés de décroissance caractéristique corrélées en temps et en position pour isoler les noyaux d'intérêt. La spectroscopie d'électrons de conversion interne du 251Fm a été réalisée pour la première fois. Ces mesures ont permis d'établir les multipolarités de plusieurs transitions et de quantifier le rapport de mélange M2/E3 dans la désintégration de l'isomère 5/2+. Le B (E3) valeur extraite est comparée à celles des autres membres de la chaîne isotonique N=151 et les calculs QRPA utilisant l'interaction effective de Gogny.Au cours de ce travail, une nouvelle méthode graphique d’extraction des rapports de mélange de transitions nucléaires a été développé. Cette méthode intuitive et illustrative et ses limites d'application, ainsi que certains aspects du calcul des rapports de mélange au-delà de ces limites, sont décrites et discutées.Les détecteurs silicium double-face à strips (DSDS) sont largement utilisés en spectrométrie nucléaire, en particulier au plan focal de séparateurs pour détecter l'implantation et la désintégration ultérieure des noyaux les plus lourds. Il a été constaté que la présence de strips mécaniquement déconnectés sur une face du DSDS peut conduire à l'apparition de pics d'énergie abaissée sur la face opposée en raison de la variation de la capacité totale. Cet effet, ainsi que les méthodes de correction du spectre, ont été étudiés et discutés. L'utilisation de simulations GEANT4 pour résoudre les effets de sommation α-ECI dans le DSDS et pour contraindre les coefficients de conversion interne des transitions impliquées dans la désexcitation du noyau d’intérêt est présentée à l’aide de l’exemple du 221Th.Une bonne partie des travaux ont été consacrés à la R&D pour un nouveau système électronique numérique pour le spectromètre GABRIELA et aux tests comparatifs de plusieurs cartes d'acquisition numériques. Les résultats de ces tests, ainsi que les algorithmes de traitement numérique du signal mis en œuvre pour une analyse non biaisée hors ligne sont présentés. / One of the major challenges of modern nuclear physics is to understand the nuclear structure of the heaviest elements. Fission barriers calculated within the macroscopic liquid drop model fail to explain the stability of nuclei with a number of protons Z≥90. Transfermium elements (Z≥100) have a vanishing liquid-drop barrier and are solely stabilized by quantum shell effects. They provide a unique laboratory to study the evolution of nuclear structure under the extreme conditions of large mass and strong Coulomb force. Though many theories agree on the existence of an “Island of Stability”, the predictions on its exact location in terms of number of protons and neutrons vary greatly. Hence the systematic study of transfermium nuclei is essential to constrain theoretical models and to get a better understanding of the evolution of nuclear shells.The interplay between single-particle and collective degrees of freedom in 251Fm was investigated by means combined internal conversion electron (ICE) and γ-ray spectroscopy. Excited states in 251Fm were populated via the α-decay of 255No produced in the two following fusion-evaporation reactions: 208Pb(48Ca, 1n)255No and 209Bi(48Ca, 2n)255Lr. The experiments were performed at the FLNR, JINR, Dubna. The intense beams were delivered by the U-400 cyclotron and the separators VASSILISSA or SHELS were used to select fusion evaporation residues. At their focal planes the GABRIELA spectrometer was used to perform a time and position correlated measurement of the characteristic decay properties to further isolate the nuclei of interest. ICE spectroscopy of 251Fm was performed for the first time. These measurements allowed to establish the multipolarities of several transitions in 251Fm and to quantify the M2/E3 mixing ratio in the decay of the low-lying 5/2+ isomer. The extracted B(E3) value is compared to those found in other members of the N=151 isotonic chain and to the QRPA calculations using the Gogny effective interaction.During this work, a novel graphical method of extracting mixing ratios for nuclear transitions has been developed. This intuitive and illustrative method and it’s limits of applicability, as well as certain aspects of the calculation of mixing ratios beyond these limits, are described and discussed.Double-sided silicon strip detectors (DSSD) are widely used in nuclear spectrometry, in particular at the focal plane of separators to detect the implantation and subsequent decay of the heaviest nuclei. It was found that the presence of mechanically disconnected strips on one face of the DSSD may lead to the occurrence of lower energy peaks on the opposite face due to the change of the total capacitance. This effect, along with the methods of restoring the correct spectra, has been studied and discussed. The use of GEANT4 simulations for resolving α-ICE summing in the DSSD and for constraining the internal conversion coefficients of the transitions involved in the decay of the nucleus of interest is presented with the example of 221Th.A significant part of the thesis work was dedicated to the R&D for a new digital electronics system for the GABRIELA spectrometer and to the comparative tests of several digital acquisition cards. The results of these tests, as well as the digital signal processing algorithms implemented for an unbiased off-line analysis are presented.
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This Creature, Bride of ChristBober, Nicholas Bradburn 05 1900 (has links)
This Creature, Bride of Christ is a composition for soprano, alto flute, viola, marimba, and computer running custom software for live interactive performance in the Max/MSP environment. The work is a setting of excerpts from The Book of Margery Kempe, an early autobiographical manuscript depicting the life of a Christian mystic. The thesis discusses the historical, sociological, and musical context of the text and its musical setting; the use of borrowed materials from music of John Dunstable, Richard Wagner, and the tradition of change ringing; and the technologies used to realize the computer accompaniment. A score of the work is also included in the appendix.
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Efficient LU Factorization for Texas Instruments Keystone Architecture Digital Signal Processors / Effektiv LU-faktorisering för Texas Instruments digitala signalprocessorer med Keystone-arkitekturNetzer, Gilbert January 2015 (has links)
The energy consumption of large-scale high-performance computer (HPC) systems has become one of the foremost concerns of both data-center operators and computer manufacturers. This has renewed interest in alternative computer architectures that could offer substantially better energy-efficiency.Yet, the for the evaluation of the potential of these architectures necessary well-optimized implementations of typical HPC benchmarks are often not available for these for the HPC industry novel architectures. The in this work presented LU factorization benchmark implementation aims to provide such a high-quality tool for the HPC industry standard high-performance LINPACK benchmark (HPL) for the eight-core Texas Instruments TMS320C6678 digitalsignal processor (DSP). The presented implementation could perform the LU factorization at up to 30.9 GF/s at 1.25 GHz core clock frequency by using all the eight DSP cores of the System-on-Chip (SoC). This is 77% of the attainable peak double-precision floating-point performance of the DSP, a level of efficiency that is comparable to the efficiency expected on traditional x86-based processor architectures. A presented detailed performance analysis shows that this is largely due to the optimized implementation of the embedded generalized matrix-matrix multiplication (GEMM). For this operation, the on-chip direct memory access (DMA) engines were used to transfer the necessary data from the external DDR3 memory to the core-private and shared scratchpad memory. This allowed to overlap the data transfer with computations on the DSP cores. The computations were in turn optimized by using software pipeline techniques and were partly implemented in assembly language. With these optimization the performance of the matrix multiplication reached up to 95% of attainable peak performance. A detailed description of these two key optimization techniques and their application to the LU factorization is included. Using a specially instrumented Advantech TMDXEVM6678L evaluation module, described in detail in related work, allowed to measure the SoC’s energy efficiency of up to 2.92 GF/J while executing the presented benchmark. Results from the verification of the benchmark execution using standard HPL correctness checks and an uncertainty analysis of the experimentally gathered data are also presented. / Energiförbrukningen av storskaliga högpresterande datorsystem (HPC) har blivit ett av de främsta problemen för såväl ägare av dessa system som datortillverkare. Det har lett till ett förnyat intresse för alternativa datorarkitekturer som kan vara betydligt mer effektiva ur energiförbrukningssynpunkt. För detaljerade analyser av prestanda och energiförbrukning av dessa för HPC-industrin nya arkitekturer krävs väloptimerade implementationer av standard HPC-bänkmärkningsproblem. Syftet med detta examensarbete är att tillhandhålla ett sådant högkvalitativt verktyg i form av en implementation av ett bänkmärkesprogram för LU-faktorisering för den åttakärniga digitala signalprocessorn (DSP) TMS320C6678 från Texas Instruments. Bänkmärkningsproblemet är samma som för det inom HPC-industrin välkända bänkmärket “high-performance LINPACK” (HPL). Den här presenterade implementationen nådde upp till en prestanda av 30,9 GF/s vid 1,25 GHz klockfrekvens genom att samtidigt använda alla åtta kärnor i DSP:n. Detta motsvarar 77% av den teoretiskt uppnåbara prestandan, vilket är jämförbart med förväntningar på effektivteten av mer traditionella x86-baserade system. En detaljerad prestandaanalys visar att detta tillstor del uppnås genom den högoptimerade implementationen av den ingående matris-matris-multiplikationen. Användandet av specialiserade “direct memory access” (DMA) hårdvaruenheter för kopieringen av data mellan det externa DDR3 minnet och det interna kärn-privata och delade arbetsminnet tillät att överlappa dessa operationer med beräkningar. Optimerade mjukvaruimplementationer av dessa beräkningar, delvis utförda i maskinspåk, tillät att utföra matris-multiplikationen med upp till 95% av den teoretiskt nåbara prestandan. I rapporten ges en detaljerad beskrivning av dessa två nyckeltekniker. Energiförbrukningen vid exekvering av det implementerade bänkmärket kunde med hjälp av en för ändamålet anpassad Advantech TMDXEVM6678L evalueringsmodul bestämmas till maximalt 2,92 GF/J. Resultat från verifikationen av bänkmärkesimplementationen och en uppskattning av mätosäkerheten vid de experimentella mätningarna presenteras också.
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Clutter Removal in Single Radar Sensor Reflection Data via Digital Signal ProcessingKazemisaber, Mohammadreza January 2020 (has links)
Due to recent improvements, robots are more applicable in factories and various production lines where smoke, fog, dust, and steam are inevitable. Despite their advantages, robots introduce new safety requirements when combined with humans. Radars can play a crucial role in this context by providing safe zones where robots are operating in the absence of humans. The goal of this Master’s thesis is to investigate different clutter suppression methods for single radar sensor reflection data via digital signal processing. This was done in collaboration with ABB Jokab AB, Sweden. The calculations and implementation of the digital signal processing algorithms are made with Octave. A critical problem is false detection that could possibly cause irreparable damage. Therefore, a safety system with an extremely low false alarm rate is desired to reduce costs and damages. In this project, we have studied four different digital low pass filters: moving average, multiple-pass moving average, Butterworth, and window-based filters. The results are compared, and it is ascertained that all the results are logically compatible, broadly comparable, and usable in this context.
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Probability Density Function Estimation Applied to Minimum Bit Error Rate Adaptive FilteringPhillips, Kimberly Ann 28 May 1999 (has links)
It is known that a matched filter is optimal for a signal corrupted by Gaussian noise. In a wireless environment, the received signal may be corrupted by Gaussian noise and a variety of other channel disturbances: cochannel interference, multiple access interference, large and small-scale fading, etc. Adaptive filtering is the usual approach to mitigating this channel distortion. Existing adaptive filtering techniques usually attempt to minimize the mean square error (MSE) of some aspect of the received signal, with respect to the desired aspect of that signal. Adaptive minimization of MSE does not always guarantee minimization of bit error rate (BER). The main focus of this research involves estimation of the probability density function (PDF) of the received signal; this PDF estimate is used to adaptively determine a solution that minimizes BER. To this end, a new adaptive procedure called the Minimum BER Estimation (MBE) algorithm has been developed. MBE shows improvement over the Least Mean Squares (LMS) algorithm for most simulations involving interference and in some multipath situations. Furthermore, the new algorithm is more robust than LMS to changes in algorithm parameters such as stepsize and window width. / Master of Science
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SIGNALBEHANDLING MED AVANCERAD BLUETOOTH-TEKNIK OCH OPTIMERADE OPERATIVSYSTEM : Optimera audiosystemet i ett avancerat inbyggt system med en fler-trådad programvara och synkroniserings mekanism / SIGNAL PROCESSING WITH ADVANCED BLUETOOTH TECHNOLOGY AND OPTIMIZED OPERATING SYSTEMS : Optimize the audio system in an advanced embedded system with a multi-threading software and synchronization mechanismIbrahim, Omar January 2023 (has links)
This study is about replacing an old bluetooth module with a new variant, namely the BM83 which is an integrated circuit that contains an internal DSP circuit, profiles and important functions such as noise reduction, acoustic echo removal and EQ filtering. The purpose of this study is to replace the old module with the BM83, as well as explore the internal DSP circuit in the BM83. The goal is to develop the audio system with a high performance bluetooth and explore the BM83's built-in DSP functions and its profiles to optimize sound quality. This study takes different methods and performs different experiments to test the ability of BM83 to replace RN52 in a DSP platform. In addition, it was proposed that an audiosystem should be managed in an operating system with the idea of optimizing data transfer by using some of new operating system mechanism methods. In this study, the differences between BM83 and RN52 were discussed in terms of their profiles, built-in CODEC and DSP algorithm.This study provides how SPP, A2DP and HFP can be used together when the BM83 is controlled by a DSP platform. In addition, it was tested how A2DP and HFP have a great importance in providing events that a DSP platform can decide on and how it chooses its source depending on these events. In addition, the data communication between the BM83 and an STM32F7 was tested via the SPP protocol, with the idea that any data would be sent and received via SPP without loss in data transmission. In conclusion, it was discussed what type of data communication is used between BM83 and an MCU in comparison between RN52 and how the built-in DSP circuit and itsprofiles are important for future research. This project was funded by the Hearing Research Foundation in project FA21-0017 and was carried out under the supervision of Amin Saremi. / Denna studie handlar om att ersätta en gammal bluetooth modul med en ny variant, nämligen BM83 som är en integrerad krets som innehåller en interna DSP krets, profiler och viktiga funktioner som brusreducering, akustisk ekoborttagning och EQ-filtrering. Syftet med denna studie är att ersätta den gamla modulen med BM83, samt utforska den interna DSP kretsen i BM83. Målet är att utveckla ljudsystemet med en högprestanda bluetooth och utforska BM83:s inbyggda DSP-funktioner och dess profilerför att optimera ljudkvalitet. Denna studie tar olika metoder och utför olika experiment för att testa BM83:s förmåga att ersätta RN52 i en DSP plattform. Dessutom föreslogs om att hur ett ljudsystem skulle hanteras i ett operativsystem med tanken på att optimera dataöverföringen. I denna studie diskuterades skillnaderna mellan BM83 och RN52 när det gäller deras profiler, inbyggda CODEC- och DSP-algoritmen. I denna studie belystes hur SPP, A2DP och HFP användes tillsammans när BM83 styrdes av en DSP plattform. Dessutom testades hur A2DP och HFP har en stor betydelse för att tillhandahålla händelser som kan en DSP plattform bestämma sig av och hur den väljer sin källa beroende på dessa händelser. Dessutom testades datakommunikationen mellan BM83 och en STM32F7 via SPP protokollet, med tanken på att valfri data skulle skickas och tas emot via SPP utan förlust i dataöverföring. Avslutningsvis diskuterades vilken typ av datakommunikation används mellan BM83 ochen MCU i jämförelse mellan RN52 och hur den inbyggda DSP kretsen och dess profiler är viktiga för framtida forskningar. Detta projekt finansierades av Hörselforskningsfonden i projekt FA21-0017 och utfördes under uppsikt av Amin Saremi.
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Lokalisering av brunnar i ELISpotModahl, Ylva, Skoglund, Caroline January 2019 (has links)
Health is a fundamental human right. To increase global health, research in the medical sector is of great importance. Decreasing time consumption of biomedical testing could accelerate the research and development of new drugs and vaccines. This could be achieved by automation of biomedical analysis, using computerized methods. In order to perform analysis on pictures of biomedical tests, it is important to identify the area of interest (AOI) of the test. For example, cells and bacteria are commonly grown in petri dishes, in this case the AOI is the bottom area of the dish, since this is where the object of analysis is located.This study was performed with the aim to compare a few computerized methods for identifying the AOI in pictures of biomedical tests. In the study, biomedical images from a testing method called ELISpot have been used. ELISpot uses plates with up to 96 circular wells, where pictures of the separate wells were used in order to find the AOI corresponding to the bottom area of each well. The focus has been on comparing the performance of three edge detection methods. More specifically, their ability to accurately detect the edges of the well. Furthermore, a method for identifying a circle based on the detected edges was used to specify the AOI.The study shows that methods using second order derivatives for edge detection, gives the best results regarding to robustness.
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Digital Back End Development and Interference Mitigation Methods for Radio Telescopes with Phased-Array FeedsBlack, Richard Allen 20 August 2014 (has links) (PDF)
The Brigham Young University (BYU) Radio Astronomy group, in collaboration with Cornell University, the University of Massachusetts, and the National Radio Astronomy Observatory (NRAO), have in recent years developed and deployed PAF systems that demonstrated the advantages of PAFs for astronomy. However, these systems lacked the necessary bandwidth and acquisition times to be scientifically viable. This thesis outlines the development of a 20-MHz bandwidth system that can acquire for much longer periods of time and across much larger bandwidths than previous BYU systems. A report of the deployment of this system on the 305-meter reflector at the Arecibo Observatory in Puerto Rico is also summarized.The Commonwealth Scientific and Industrial Research Organisation (CSIRO) is currently constructing a PAF-equipped synthesis imaging array named the Australian Square Kilometre Array Pathfinder (ASKAP) that offers great promise for widening FOVs and enhancing RFI mitigation techniques. Previous work in RFI mitigation has demonstrated effective cancellation for synthesis imaging arrays under the assumption that the processing bandwidth is narrowband and correlator dump times are short. However, these assumptions do not necessarily reflect real-world instrument limitations. This thesis explores simulated adaptive array cancellation algorithm effectiveness as applied on the ASKAP instrument given realistic bandwidths and correlator dump times. The results demonstrate that active RFI mitigation performed across long baselines is largely ineffectual.
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