• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 80
  • 52
  • 25
  • 15
  • 15
  • 8
  • 5
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • Tagged with
  • 246
  • 50
  • 30
  • 30
  • 29
  • 22
  • 22
  • 20
  • 20
  • 18
  • 18
  • 15
  • 14
  • 14
  • 14
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Implementace softwarového rádia do FPGA / Implementation of software radio into FPGA

Šrámek, Petr January 2009 (has links)
The common objective of this project is implementation of software defined radio (SDR) into FPGA. The text contains review and comparison of several hardware concepts intended for SDRs implementation then the methods for digital implementation of various components of radios as the filters, mixers and others are mentioned. Part of the text introduces used hardware platform and describes software support for designing, simulations and implementation into hardware. Significant part of project describes complex of external hardware components as filter, amplifier and control panel designed and built within the project realization. But the main part of project demonstrates design of the software solution of radio receiver. There is specified architecture of radio for FM broadcast receiving, next the more complex systems with carrier recovery algorithm are presented. These systems are able to work with AM, BPSK and QPSK modulations. It is possible to implement all these receivers into hardware and verify their operation. The practical laboratory theme has been outlined within the project run.
182

Parameters Selection for Optimising Time-Frequency Distributions and Measurements of Time-Frequency Characteristics of Nonstationary Signals

Sucic, Victor January 2004 (has links)
The quadratic class of time-frequency distributions (TFDs) forms a set of tools which allow to effectively extract important information from a nonstationary signal. To determine which TFD best represents the given signal, it is a common practice to visually compare different TFDs' time-frequency plots, and select as best the TFD with the most appealing plot. This visual comparison is not only subjective, but also difficult and unreliable especially when signal components are closely-spaced in the time-frequency plane. To objectively compare TFDs, a quantitative performance measure should be used. Several measures of concentration/complexity have been proposed in the literature. However, those measures by being derived with certain theoretical assumptions about TFDs are generally not suitable for the TFD selection problem encountered in practical applications. The non-existence of practically-valuable measures for TFDs' resolution comparison, and hence the non-existence of methodologies for the signal optimal TFD selection, has significantly limited the use of time-frequency tools in practice. In this thesis, by extending and complementing the concept of spectral resolution to the case of nonstationary signals, and by redefining the set of TFDs' properties desirable for practical applications, we define an objective measure to quantify the quality of TFDs. This local measure of TFDs' resolution performance combines all important signal time-varying parameters, along with TFDs' characteristics that influence their resolution. Methodologies for automatically selecting a TFD which best suits a given signal, including real-life signals, are also developed. The optimisation of the resolution performances of TFDs, by modifying their kernel filter parameters to enhance the TFDs' resolution capabilities, is an important prerequisite in satisfying any additional application-specific requirements by the TFDs. The resolution performance measure and the accompanying TFDs' comparison criteria allow to improve procedures for designing high-resolution quadratic TFDs for practical time-frequency analysis. The separable kernel TFDs, designed in this way, are shown to best resolve closely-spaced components for various classes of synthetic and real-life signals that we have analysed.
183

Marketing strategies in the UK classical music business : the significance of 1989

Carboni, Marius Julian January 2011 (has links)
The process by which the classical music business operates in the UK changed significantly through the marketing of a classical music recording which took place in 1989. EMI’s recording of Vivaldi’s work Four Seasons with the violinist Nigel Kennedy was given a unique marketing campaign for a classical music recording. Instead of the traditional marketing approach for a classical music release, pop marketing techniques were employed. In a different but related development, in 1990, the first of the Three Tenors concerts was held in Rome to mark the final match of the 1990 Fédération Internationale de Football Association’s (FIFA) world cup competition. The success of this second record campaign lay in the novelty of three tenors performing together at a football competition. The result was classical music achieving worldwide exposure through global radio and television broadcasts. Both case studies help further classical music as a form of popular culture. Earlier precedent demonstrates pieces of classical music being used for adverts or films and becoming popular. For example Ravel’s Bolero was used in a seduction scene in the film 10 between Bo Derek and Dudley Moore in 1984, and by ice-skaters Torvill and Dean in the same year for the final of the 1984 Winter Olympics. Another example is Orff’s Carmina Burana sections of which have been used for aftershave and lager adverts as well as being sung at football matches. Because the reach of the audience is larger than that in a traditional classical music setting, the pieces achieve a mass cultural perspective in this context. My thesis examines the impact that the success of the Four Seasons and Three Tenors releases had on the classical music business and the development in marketing and selling techniques that emanated from their success. Examples of marketing campaigns post the Four Seasons are included to show the extent of non-traditional classical marketing techniques used subsequently by the classical music industry, some of which I devised and implemented. My research also analyses how trading over the internet has had an impact on the music business as a whole, and how the classical music sector has followed the pop area of the music industry in creating different ways of selling to traditional and new consumers through online trading. This part of the thesis focuses on the period between 2000-2010, especially from 2006 when developments in this field progressed. My study will draw on a Case Study approach using multiple data collection methods. Also employed is descriptive analysis using a combination of qualitative and quantitative techniques, in particular through industry reports. The reasons for the sales success of both recordings are examined in my thesis. The Four Seasons achieved 2 million sales and an entry into the Guinness Book of Records as the best-selling classical music recording of all time at that point. The recording of the 1990 Three Tenors concert and the successive recordings of similar concerts in 1994 and 1998 led to these albums becoming the all-time best-selling classical recordings. For example, worldwide sales for the 1990 recording reached over 12 million CDs, cassettes and videos combined and 23 million for the 1990, 1994 and 1998 Three Tenors recordings. These projects not only gave increased exposure to the classical music genre by expanding its traditional consumer reach, they also created a force for change in business models affecting the marketing and visibility of classical music since 1989. A further significant factor in the success of these vocal recordings (as well as the chance for classical music to be heard outside its traditional boundary) was the use of the arresting aria Nessun dorma from Puccini’s opera Turandot. This was sung by Pavarotti and used by the BBC for all its programmes broadcasting the 1990 football matches in the competition. The effect of internet selling and downloading on the music business was encouraged by the creation of Apple’s iTunes program in 2001. The invention of the iPod in 2002 and the legal entity of Napster in 2004 led to much increased accessibility of music. For classical music with its long movements and being part of a slow-moving market (compared to pop music), this area of the business only witnessed an increase in activity through the expansion of Broadband nationally during 2006 and 2007, reaching 70% in 2009 (discussed on page 90, chapter 4). Since then, the growth of classical music e-tailers has forged a new way of operating in the classical music field. The thesis will give examples of the leading companies trading over the internet and their influence on the classical music market. Contributions from practitioners in the music business inform my thesis through their own witnessing of changes in the classical music business since the Four Seasons campaign. My own experience as a former Head of Press and Promotion for both Decca Classics and EMI Classics, and also currently as a marketing and business consultant for classical music organisations, offers a useful and relevant addition to my research. My contribution to knowledge is to identify the adaptation of pop music marketing tools by the classical music industry over a 20 year time frame. My close involvement in the EMI Four Seasons campaign places me in a unique position to identify and evaluate the significance of the publicity campaign of that recording not only at that time but in the years that followed.
184

A New Power Storage, Cooling Storage, and Water Production Combined Cycle (PCWCC)

Ghashami, Bahman January 2016 (has links)
Fresh water shortage and hot weather are common challenges in many countries of the world. In the other hand, the air conditioning systems which are used for indoor cooling cause peak electricity demand during high temperatures hours. This peak hour demand is very important since it is more expensive and mainly is supplied by fossil fuel power plants with lower efficiencies compare to base load fossil fuel or renewable owe plants. Moreover, these peak electricity load fossil fuel power plants cause higher green house gas emission and other environmental effects. So, all these show that any solution for these problems could make life better in those countries and all over the world.In this thesis, a new idea for a Power storage, Cooling storage, and Water production Combined Cycle (PCWCC) is introduced and reviewed. PCWCC is combination of two thermal cycles, Ice Thermal Energy Storage (ITES) and desalination by freezing cycle, which are merged together to make a total solution for fresh water shortage, required cooling, and high peak power demand. ITES is a well known technology for shifting the electricity demand of cooling systems from peak hours to off-peak hours and desalination by freezing is a less known desalination system which is based on the fact that the ice crystals are pure and by freezing raw water and melting resulted ice crystals, pure water will be produced. These two systems have some common processes and equations and this thesis shows that by combining them the resulted PCWCC could be more efficient than each of them. In this thesis, the thermodynamic equations and efficiencies of each PCWCC sub-systems are analyzed and the resulted data are used in finding thermodynamics of PCWCC itself. Also, by using reMIND software, which uses Cplex to find the best combinations of input/output and related processes, the cost of produced fresh water and cooling from PCWCC is compared with total cost of fresh water and cooling produced by each sub-systems of PCWCC in three sample cities all over the world, Kerman, Dubai, and Texas. These cities are chosen since they have similar ambient temperature trend with different electricity and fresh water tariff's. The results show that, the PCWCC is economical where there is a significant electricity price difference between ice charging and ice melting hours, off-peak and peak hours, of the day or when the fresh water price is high compare to electricity price. The results also show that how the revenue from fresh water could cover the used electricity cost and make some income as well.
185

Improvement of Word Discrimination in Noise with a Personal FM System in Children with Down Syndrome

Lett, Kim, Nordberg, J., Schairer, Kim S. 21 February 2012 (has links)
No description available.
186

Climatologie du transport des aérosols désertiques au-dessus de l'Atlantique vers la région Caraïbe. / Climatology of desert oust transportation over the Atlantic toward Caribbean area

Euphrasie-Clotilde, Lovely 09 May 2018 (has links)
La région Caraïbe est régulièrement survolée par des masses d'air chargées en poussières désertiquesd'origines saharienne et sub-saharienne. Pour quatre îles de l'arc antillais : Porto Rico, Guadeloupe, Martinique etBarbade; nous avons évalué l'origine de la pollution particulaire et son impact sur la qualité de l'air, en effectuant uneétude statistique des évènements de poussière qui s'appuie sur les réseaux de mesure de qualité de l'air implantés surchacune des îles, sur le réseau international de mesures photométriques AERONET et sur les données deradiosondages réalisés localement. La première étape de notre travail, a visé à définir ce que l'on pouvait qualifier« d'épisode de poussières désertiques» dans notre région en établissant des critères utilisant le jeu de données dontnous disposions. Deuxièmement, nous avons réalisé une étude climatologique des évènements poussiéreux dans laCaraïbe au cours de la dernière décennie (2006-2016). Le troisième axe de la thèse repose sur la caractérisation de lataille des particules afin de mettre en relief les effets du transport à longue distance. Nous avons clôturé notre étudepar la description de la structure verticale de l'atmosphère de la zone tropicale en situation de « brumes de poussièredésertique » afin d'observer les effets thermodynamiques des aérosols minéraux sur la couche atmosphérique. Ladéfinition des évènements de brumes désertique que nous avons adoptée nous a permis de prendre en considérationune grande partie des évènements poussiéreux affectant l'arc antillais, ce qui nous a amené à mieux cerner le cycle detranspon des poussièl'es désertiques au terme d'une étude basée sur onze années de données. / The Caribbean region is regularly flown over by desert dust air masses (Saharan Air Layer) corne fromSaharan and sub-Saharan area. For four islands of the West Indies arc: Puerto Rico, Guadeloupe, Martinique andBarbados; we assessed the origin of polluting particles and their impact on air quality, by performing a statistical andclimatological study of desert dust events. We therefore based on the air quality measurement networks, theinternational AEronet RObotic NETwork (AERONET) photometric measurements installed on each of these islands.And finally, this study builds on sounding data produced locally.The first step in our work was to define and describe an "desert dust episode" in the tropical region. Thus, we studiedthe relationship of correlation between Aerosols Optical Depth (AOD), Angstrom Exponent (AE, characterizing theparticle size) and Particulate Matter 10 microns or Jess in diameter (PM10 data). On the other hand, the radiativeproperties (Single Scattering Albedo, refractive indexes) have been used to highlight sea sait contribution (coarseparticle just as dust particle) that significantly influences PM10 measurement due to the geographical context ofCaribbean islands. Our investigations led us to propose a daily PM 10 threshold at 35 μg m·3 that mainly associatedwith desert dust phenomenon. This latter is more suited for the Lesser Antilles compared to the European PM10threshold related to desert dust events: 50 μg m·3.As a result, a climatological study of dusty events in the Caribbean during the last decade (2006-2016) is carried out.Four dust seasons were identified: the high dust season (May to August), the low dust season (November to February,and two intermediate periods (March to April, September to October). We then examine dust exportation fromAfrican coasts toward the Lesser Antilles (Puerto Rico, Guadeloupe Martinique and Barbados) by mean of backtrajectories[Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) mode\] displaying atmosphericcirculation day-to-day over the Atlantic Ocean.This analysis enabled us to better understand the seasonal cycle of desert dust transportation, specific to each island(Puerto Rico, Guadeloupe, Martinique, Barbados); while most of the previous studies treats average data including thewhole Caribbean zone. lt emerges that islands are not affected by dust events similarly, i.e. by intensity of events andits includes some variation in dust periods.Lastly, we describe the vertical structure of the tropical zone atmosphere in situation of "desert dust events" and"Non-desert dust event" to observe the thermodynamic effects of minerai aerosols on the Caribbean atmosphericlayer. This analysis allowed us to consider desert dust aerosols effects on the thermodynamic parameters(Temperature and humidity) during the dry-season (November to April) named "câreme" and the wet season (May toOctober) named "hivernage".
187

The Fractional Fourier Transform and Its Application to Fault Signal Analysis

Duan, Xiao 2012 May 1900 (has links)
To a large extent mathematical transforms are applied on a signal to uncover information that is concealed, and the capability of such transforms is valuable for signal processing. One such transforms widely used in this area, is the conventional Fourier Transform (FT), which decomposes a stationary signal into different frequency components. However, a major drawback of the conventional transform is that it does not easily render itself to the analysis of non-stationary signals such as a frequency modulated (FM) or amplitude modulated (AM) signal. The different frequency components of complex signals cannot be easily distinguished and separated from one another using the conventional FT. So in this thesis an innovative mathematical transform, Fractional Fourier Transform (FRFT), has been considered, which is more suitable to process non-stationary signals such as FM signals and has the capability not only of distinguishing different frequency components of a multi-component signal but also separating them in a proper domain, different than the traditional time or frequency domain. The discrete-time FRFT (DFRFT) developed along with its derivatives, such as Multi-angle-DFRFT (MA-DFRFT), Slanted Spectrum and Spectrogram Based on Slanted Spectrum (SBSS) are tools belonging to the same FRFT family, and they could provide an effective approach to identify unknown signals and distinguish the different frequency components contained therein. Both artificial stationary and FM signals have been researched using the DFRFT and some derivative tools from the same family. Moreover, to accomplish a contrast with the traditional tools such as FFT and STFT, performance comparisons are shown to support the DFRFT as an effective tool in multi-component chirp signal analysis. The DFRFT taken at the optimum transform order on a single-component FM signal has provided higher degree of signal energy concentration compared to FFT results; and the Slanted Spectrum taken along the slant line obtained from the MA-DFRFT demonstration has shown much better discrimination between different frequency components of a multi-component FM signal. As a practical application of these tools, the motor current signal has been analyzed using the DFRFT and other tools from FRFT family to detect the presence of a motor bearing fault and obtain the fault signature frequency. The conclusion drawn about the applicability of DFRFT and other derivative tools on AM signals with very slowly varying FM phenomena was not encouraging. Tools from the FRFT family appear more effective on FM signals, whereas AM signals are more effectively analyzed using traditional methods like spectrogram or its derivatives. Such methods are able to identify the signature frequency of faults while using less computational time and memory.
188

Recalage d'image de la tomographie optique diffuse de fluorescence (fDOT) et la tomographie par émission de positons (TEP) et le développement de tomographie optique en multi-angle

Tong, Xiao 24 October 2012 (has links) (PDF)
Ce travail de thèse concerne le traitement d'image fDOT (fDOT pour fluorescence diffuse optical tomography) suit vers deux axes. Le recalage d'images fDOT à l'aide de l'imagerie TEP (tomographie par émission de positons) et l'amélioration des reconstructions fDOT à l'aide de miroirs pour collecter des projections complémentaires. Il est présenté en deux parties : Dans la première partie, une méthode automatique pour recaler les images de fDOT avec les images de Tomographie par Emission de Positons (TEP) développée dans le but de corréler l'ensemble des informations issues de chaque modalité. Cette méthode de recalage est basée sur une détection automatique de marqueurs fiduciaires présents dans les deux modalités. La particularité de cette méthode est l'utilisation de l'image de surface obtenue en fDOT, qui sert à identifier la position en Z des marqueurs fiduciaires dans les images optiques. Nous avons testé cette méthode sur un modèle de souris porteuses de xénogreffes de tumeurs de cellules cancéreuses MEN2A qui imitent un carcinome thyroïdien médullaire humain, après une double injection de traceur radioactif : [18F]2-fluoro-2-Deoxy-D-glucose (FDG) pour l'imagerie TEP et un traceur optique d'infrarouge fluorescent, le Sentidye. Grâce à la précision de notre méthode, nous arrivons à démontrer que le signal Sentidye est présent à la fois dans la tumeur et les vaisseaux environnants [1]. La qualité des images fDOT est dégradée selon l'axe Z du fait d'un nombre limité de projections pour la reconstruction. Dans la deuxième partie, le travail s'est orienté vers une nouvelle méthode de reconstruction d'images fDOT à partir d'un nouveau système d'acquisition multi-angulaire avec deux miroirs placés de chaque côté de l'animal. Ce travail a été mené en collaboration avec le département CS d'University College London (UCL), partenaire du projet Européen FMT-XCT. Le logiciel TOAST développé par cette équipe a été utilisé comme source pour l'algorithme de reconstruction, et modifié pour s'adapter à notre problématique. Après plusieurs essais concernant l'ajustement des paramètres du programme, nous avons appliqué cette méthode sur un fantôme réaliste des tissus biologiques et chez la souris. Les résultats montrent une amélioration de l'image reconstruite d'un fantôme semi-cylindrique et de l'image de rein chez la souris, pour lesquelles la méthode des miroirs est supérieure à la méthode classique sans miroir. Malgré tout, nous avons observé que les résultats étaient très sensibles à certains paramètres, d'où une performance de reconstruction variable d'un cas à l'autre. Les perspectives futures concernent l'optimisation des paramètres afin de généraliser l'approche multi-angle.
189

Nyhetsradio : Om skillnaderna i korta riksnyhetssändningar mellan två kommersiella radiostationer och public serviceradion.

Olausson, Daniel, Sundberg, Erik January 2008 (has links)
The purpose of this BA-thesis was to learn the differences in news broadcasts between one public service radio channel and two commercial radio channels. To do this we used a quantitative analysis method to examine the content of the news broadcasts and then we conducted in-depth interviews with several people working with the different radio channels using a qualitative research interview method to learn their views on news and news broadcasting. We measured the differences between the channels in six areas: subject, headline, news presentation, gender, advertising and sources. Our two main theories were normative theory and media logic. The results found that there were several major differences between the public service radio channel and the two commercial radio channels. Apart from several important differences in the six measured categories we also found that the sound and tone in the public service radio channel was very different from the two commercial radio channels. We also found the public service radio channels news broadcasts to be more serious than the two commercials ones’.
190

Quality Measures of Halftoned Images (A Review)

Axelson, Per-Erik January 2003 (has links)
<p>This study is a thesis for the Master of Science degree in Media Technology and Engineering at the Department of Science and Technology, Linkoping University. It was accomplished from November 2002 to May 2003. </p><p>Objective image quality measures play an important role in various image processing applications. In this paper quality measures applied on halftoned images are aimed to be in focus. Digital halftoning is the process of generating a pattern of binary pixels that create the illusion of a continuous- tone image. Algorithms built on this technique produce results of very different quality and characteristics. To evaluate and improve their performance, it is important to have robust and reliable image quality measures. This literature survey is to give a general description in digital halftoning and halftone image quality methods.</p>

Page generated in 0.0491 seconds