Aquesta Tesi Doctoral se centra en el disseny d'un nou linealitzador de Predistorsió Digital (Digital Predistortion - DPD) capaç de compensar la dinàmica i els efectes no lineals introduïts pels Amplificadors de Potència (Power Amplifiers - PAs). Un dels trets més rellevants d'aquest nou predistorsionador digital i adaptatiu consisteix en ser deduïble a partir d'un model de PA anomenat Nonlinear Auto-Regressive Moving Average (NARMA). A més, la seva arquitectura multi-LUT (multi-Taula) permet la implementació en un dispositiu Field Programmable Gate Array (FPGA).La funció de predistorsió es realitza en banda base, per tant, és independent de la banda freqüencial on es durà a terme l'amplificació del senyal de RF, el que pot resultar útil si tenim en compte escenaris multibanda o reconfigurables. D'altra banda, el fet que aquest DPD tingui en compte els efectes de memòria introduïts pel PA, representa una clara millora de les prestacions aconseguides per un simple DPD sense memòria. En comparació amb d'altres DPDs basats en models més computacionalment complexos, com és el cas de les xarxes neuronals amb memòria (Time-Delayed Neural Networks - TDNN), la estructura recursiva del DPD proposat permet reduir el nombre de LUTs necessàries per compensar els efectes de memòria del PA. A més, la seva estructura multi-LUT permet l'escalabilitat, és a dir, activar or desactivar les LUTs que formen el DPD en funció de la dinàmica que presenti el PA.En una primera aproximació al disseny del DPD, és necessari identificar el model NARMA del PA. Un dels majors avantatges que presenta el model NARMA és la seva capacitat per trobar un compromís entre la fidelitat en l'estimació del PA i la complexitat computacional introduïda. Per reforçar aquest compromís, l' ús d'algoritmes heurístics de cerca, com són el Simulated Annealing o els Genetic Algorithms, s'utilitzen per trobar els retards que millor caracteritzen la memòria del PA i per tant, permeten la reducció del nombre de coeficients necessaris per caracteritzar-la. Tot i així, la naturalesa recursiva del model NARMA comporta que, de cara a garantir l'estabilitat final del DPD, cal dur a terme un estudi previ sobre l'estabilitat del model.Una vegada s'ha obtingut el model NARMA del PA i s'ha verificat l'estabilitat d'aquest, es procedeix a l'obtenció de la funció de predistorsió a través del mètode d'identificació predictiu. Aquest mètode es basa en la continua identificació del model NARMA del PA i posteriorment, a partir del model obtingut, es força al PA perquè es comporti de manera lineal. Per poder implementar la funció de predistorsió en la FPGA, cal primer expressar-la en forma de combinacions en paral·lel i cascada de les anomenades Cel·les Bàsiques de Predistorsió (BPCs), que són les unitats fonamentals que composen el DPD. Una BPC està formada per un multiplicador complex, un port RAM dual que actua com a LUT (taula de registres) i un calculador d'adreces. Les LUTs s'omplen tenint en compte una distribució uniforme dels continguts i l'indexat d'aquestes es duu a terme mitjançant el mòdul de l'envoltant del senyal. Finalment, l'adaptació del DPD consisteix en monitoritzar els senyals d'entrada i sortida del PA i anar duent a terme actualitzacions periòdiques del contingut de les LUTs que formen les BPCs. El procés d'adaptació del contingut de les LUTs es pot dur a terme en la mateixa FPGA encarregada de fer la funció de predistorsió, o de manera alternativa, pot ser duta a terme per un dispositiu extern (com per exemple un DSP - Digital Signal Processor) en una escala de temps més relaxada. Per validar l'exposició teòrica i provar el bon funcionalment del DPD proposat en aquesta Tesi, es proporcionen resultats tant de simulació com experimentals que reflecteixen els objectius assolits en la linealització del PA. A més, certes qüestions derivades de la implementació pràctica, tals com el consum de potència o la eficiència del PA, són també tractades amb detall. / This Ph.D. thesis addresses the design of a new Digital Predistortion (DPD) linearizer capable to compensate the unwanted nonlinear and dynamic behavior of power amplifiers (PAs). The distinctive characteristic of this new adaptive DPD is its deduction from a Nonlinear Auto Regressive Moving Average (NARMA) PA behavioral model and its particular multi look-up table (LUT) architecture that allows its implementation in a Field Programmable Gate Array (FPGA) device.The DPD linearizer presented in this thesis operates at baseband, thus becoming independent on the final RF frequency band and making it suitable for multiband or reconfigurable scenarios. Moreover, the proposed DPD takes into account PA memory effects compensation which representsan step forward in overcoming classical limitations of memoryless predistorters. Compared to more computational complex DPDs with dynamic compensation, such Time-Delayed Neural Networks (TDNN), this new DPD takes advantage of the recursive nature of the NARMA structure to relax the number of LUTs required to compensate memory effects in PAs. Furthermore, its parallel multi-LUT architecture is scalable, that is, permits enabling or disabling the contribution of specific LUTs depending on the dynamics presented by a particular PA.In a first approach, it is necessary to identify a NARMA PA behavioral model. The extraction of PA behavioral models for DPD linearization purposes is carried out by means of input and output complex envelope signal observations. One of the major advantages of the NARMA structure regards its capacity to deal with the existing trade-off between computational complexity and accuracy in PA behavioral modeling. To reinforce this compromise, heuristic search algorithms such the Simulated Annealing or Genetic Algorithms are utilized to find the best sparse delays that permit accurately reproducing the PA nonlinear dynamic behavior. However, due to the recursive nature of the NARMA model, an stability test becomes a previous requisite before advancing towards DPD linearization.Once the PA model is identified and its stability verified, the DPD function is extracted applying a predictive predistortion method. This identification method relies just on the PA NARMA model and consists in adaptively forcing the PA to behave as a linear device. Focusing in the DPD implementation, it is possible to map the predistortion function in a FPGA, but to fulfill this objective it is first necessary to express the predistortion function as a combined set of LUTs.In order to store the DPD function into a FPGA, it has to be stated in terms of parallel and cascade Basic Predistortion Cells (BPCs), which are the fundamental building blocks of the NARMA based DPD. A BPC is formed by a complex multiplier, a dual port RAM memory block acting as LUT and an address calculator. The LUT contents are filled following an uniform spacing procedure and its indexing is performed with the amplitude (modulus) of the signal's envelope.Finally, the DPD adaptation consists in monitoring the input-output data and performing frequent updates of the LUT contents that conform the BPCs. This adaptation process can be carried out in the same FPGA in charge of performing the DPD function, or alternatively can be performed by an external device (i.e. a DSP device) in a different time-scale than real-time operation.To support all the theoretical design and to prove the linearization performance achieved by this new DPD, simulation and experimental results are provided. Moreover, some issues derived from practical experimentation, such as power consumption and efficiency, are also reported and discussed within this thesis.

Bit-parallel addition can be performed using a number of adder structures with different area and latency. However, the power consumption of different adder structures is not well studied. Further, the effect of pipelining adders to increase the throughput is not well studied. In this thesis four different adders are described, implemented in VHDL and compared after synthesis. The results give a general idea of the time-delay-power tradeoffs between the adder structures. Pipelining is shown to be a good technique for increasing the circuit speed.

Teachers' use of information and communication technologies (ICT) in the classroom has largely been studied to date with a focus on what is lacking. An important aspect that seems to have been understudied is how teachers' own histories and experiences of ICT connects to their teaching practices - in essence, focussing on what is 'present' and not what is 'missing'. This study examines five teachers working in the same school, but working very differently with ICT in their classrooms. The narratives of their lived experiences highlight the acquisition of their beliefs, attitudes and their in situ behaviours about the role of ICT in the classroom. A critical look at the factors responsible for shaping such behaviours suggests the value of understanding individuals' experiences when planning for technology-utilization, rather than prescribing a "teacher-proof" (Connelly & Clandinin, 1988) approach to technology uptake.

Il est peu de notions aussi vastes que celle du non-savoir, mais le flou du caractère nécessairement négatif de sa définition s’accompagne tout de même du sentiment que la source de ce qui ne peut qu’être déterminé négativement par la pensée (non, cela n’est pas le savoir) ne peut qu’être positive. Notion à l’applicabilité infinie, parce qu’en elle vient s’abîmer tout ce qui ne peut tenir dans l’espace de la maîtrise relative à ce dont on peut dire : je sais de quoi il s’agit. Est non-savoir tout ce qui se rapporte au bouillonnement pulsionnel de la vie et à l’échéance fatale de la mort. Ce qui pousse l’homme au meurtre, au génocide, à la guerre et à la violence révolutionnaire se confond avec un contenu affectif et identitaire qui ne peut être ramené au savoir sans laisser de reste. Mais tenter de comprendre ce qui échappe à l’entendement est cela même qui relance sans cesse la réflexion comprise comme cœur du savoir. Le savoir se montre ainsi sous une extrême dépendance face à son Autre. À la lumière de cette hypothèse devant beaucoup aux découvertes de la psychanalyse, le présent mémoire s’est donné pour objectif de jeter un regard frais sur quelques grandes tensions sociopolitiques de l’Histoire; mais il a d’abord fallu évaluer philosophiquement la possibilité d’un concept de non-savoir. Des champs identitaires majeurs — révolutions totalitaires ou démocratiques, bouleversements ou synergies culturelles — sont ainsi analysés sous l’angle d’une économie pulsionnelle qui s’inscrit dans une interaction perpétuelle avec ce qui s’ébauche ici comme une économie du rapport entre non-savoir et savoir. Est ainsi produite une esquisse des rapports possibles entre la vie pulsionnelle de l’homme, le savoir institutionnel et le monde sociopolitique. / Few notions are as vast as that unknowing; but the imprecise nature of its definition is nonetheless accompagnied by the implication that what offers itself only negatively to the mind has a positive source. The applicability of the notion of unknowing is infinite; it swallows up all that resists the mastery indicated by statements about that which is. Unknowing encompasses all that belongs to the boiling drive of life and to the faceless moment of death. What leads human beings to murder, to genocide, to war and to revolutionnary violence is bound up with an affective content of identification that cannot be subsumed by knowledge without leaving a residue. Yet attempting to understand what exceeds the mind’s grasp serves as the motor of mental reflection at the heart of knowledge production itself. In this sense, knowledge is inescapably dependent on its « other ». In light of this hypothesis drawn from the domain of psychoanalysis, this thesis aims to reexamine the conceptual underpinnings of basic sociopolitical tensions in History. The conceptual impetus driving major identity movements — such as totalitarian or democratic revolutions and cultural disruptions or synergies — is analysed in terms of a libidinal or drive-oriented economy which is in perpetual interaction with what this thesis characterizes as an economy of the relation between knowing and unknowing, between knowledge and its negation.

Teachers' use of information and communication technologies (ICT) in the classroom has largely been studied to date with a focus on what is lacking. An important aspect that seems to have been understudied is how teachers' own histories and experiences of ICT connects to their teaching practices - in essence, focussing on what is 'present' and not what is 'missing'. This study examines five teachers working in the same school, but working very differently with ICT in their classrooms. The narratives of their lived experiences highlight the acquisition of their beliefs, attitudes and their in situ behaviours about the role of ICT in the classroom. A critical look at the factors responsible for shaping such behaviours suggests the value of understanding individuals' experiences when planning for technology-utilization, rather than prescribing a "teacher-proof" (Connelly & Clandinin, 1988) approach to technology uptake.

Syftet med denna studie var att få en insikt i och kunskaper om vad som gömmer sig bakom uttalanden som att man måste ha en blick och en fallenhet för det. I studien har två manliga lastbilsförare med lång erfarenhet av lastbilsföraryrket intervjuats om deras sätt att se på vilka kunskaper som behövs för att ses som en kompetent och yrkesskicklig lastbilsförare. Kunskaperna som lastbilsförarna lyfter fram är att ha en blick och en fallenhet för yrket. Studien visade att lastbilsförarna hade svårt att sätta ord på vad de menar med att ha en blick och en fallenhet för yrket. Resultatet i studien visade att det som lastbilsförarna pratar om när det gäller att ha en blick och en fallenhet för yrket bottnar i Aristoteles kunskapsbegrepp techne som ses som färdighetskunskap och fronesis som ses som förtrogenhetskunskap. Inom färdighetskunskapen ryms att ha en fallenhet för något, du har förmågan att utföra en handling. Denna förmåga utvecklas genom övning och erfarenhet, och det går inte att förutsäga hur långt en enskild förmåga kan utvecklas. Inom förtrogenhetskunskapen ryms att ha en blick för något, man kan se mönster eller beteenden som man kan tolka och se utgången av. Men, man kan inte ha en blick för något som man inte har upplevt innan. Båda kunskaperna bygger på att du har samlat på dig erfarenhet över tid. De samverkar med varandra i olika grad, beroende på personliga egenskaper, och den specifika situation de ställs inför. / The purpose of the study was to get an insight into what it is that hides behind the statement to have an eye for something and an aptitude for something. In this study i have been in contact with two male truck drivers who have a long experience from truck driving.In the study they told me what knowledge they see as needed to be seen as a competent and skilled truck driver. The knowledge that the truck drivers brings out is to have an eye and an aptitude for the profession. The study showed that truck drivers had a hard time putting into words what they mean by having an eye and an aptitude for the profession.   The results of the study showed that when it comes to having an eye and an aptitude for the profession that stems from Aristotle's concept of knowledge, techne seen as skill knowledge and phronesis seen as familiarity or intimate knowledge.Within skill knowledge fit to have an aptitude for something, you have the ability to perform an action. This ability develops with practice and experience, and it is not possible to predict how long an individual's ability can develop. Within familiarity knowledge fit to have an eye for something, you can see patterns or behaviors that can be interpreted.   But, you can´t have a look for something you have not experienced before. The knowledge is based upon what you have accumulated over time. The knowledge interacts with each other to different degrees depending on personal characteristics, and the specific situation they face.

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Made available in DSpace on 2015-05-14T12:43:27Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1454620 bytes, checksum: 20676365cee0fb8168374042cecc7603 (MD5) Previous issue date: 2010-03-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This production had the intention to monitor the emergence of language as a multimodal instance in contexts of joint attention occurred in naturalistic situations of two motherbaby dyads, from seven to seventeen months of the child. Thus we work with the multimodal envelope perspective, i.e., the fusion of three components of the dialogism look, gestures and vocal production that emerge simultaneously. We consider the concept of multimodality proposed by McNeill (1985) as a mixture of the gesture-vocal actions. The studies in language acquisition and in nonverbal communication postulate theoretical assumptions about linguistic, paralinguistic and extralinguistic elements in a dissociated way. The first ones had as primacy the observation of interlocutors speech and writing in various contexts. The second type was justified as a complement to the linguistic and the extralinguistic elements were considered as accessories used as aids to the speech. Our results show that the mother uses the multimodal composition to address herself to the child who interacts as she acquires the three basic components of the dialogism. / Esta produção teve como intuito acompanhar a emergência da língua enquanto instância multimodal em contextos de atenção conjunta vividos em situações naturalísticas de duas díades mãe-bebê, dos 07 aos 17 meses de vida da criança. Para isso trabalhamos com a perspectiva de envelope multimodal, ou seja, a mescla de três componentes da dialogia olhar, gestos e produção vocal que emergem concomitantemente. Tomamos como premissa a noção de multimodalidade proposta por McNeill (1985) como sendo a mescla das ações gesto-vocais. Os estudos em aquisição de linguagem e de comunicação não-verbal postulavam aportes teóricos a respeito de elementos lingüísticos, paralingüísticos e extralingüísticos de forma dissociada. Os primeiros tinham como primazia a observação da fala e da escrita de interlocutores em vários contextos. O segundo tipo era justificado como complemento do lingüístico e os elementos extralingüísticos eram considerados como acessórios usados como auxiliares da fala. Nossos resultados mostram que a mãe faz uso do plano de composição multimodal para dirigir-se à criança que, por sua vez, interage à medida que adquire os três componentes básicos da dialogia.

Unga barn föredrar redan från födseln att lyssna till positivt tal, vilket karaktäriserar barnriktat tal. Idenna studie kontrasterades neutral och positiv känsla i ett ordinlärningsparadigm där tittiden hos 16-månader gamla, svensktalande barn (N=12) analyserades när de testades på två påhittade ord.Målorden presenterades antingen i positivt barnriktat tal eller neutralt barnriktat tal. Detta gjordes föratt se om det positiva barnriktade talet underlättar inlärningen av nya ord. Deras tittid på detefterfrågade objektet analyserades sedan med en tvåvägs-ANOVA. Det fanns inga signifikantaskillnader mellan röstlägena. Slutsatsen som drogs var att hypotesen, att tittiden för det objekt sompresenteras i positivt tal är längre, inte kunde bekräftas men inte heller förkastas på grund av problemmed datainsamlingen samt dataanalysen. Inför framtida studier rekommenderas att utöka antaletdeltagare, samt undersöka andra variabler som kan påverka den tidiga ordinlärningen. / Already from birth young children prefer to listen to positive speech, which is a characteristic of childdirected speech. In this study neutral and positive tone was contrasted in a word-learning paradigmwhere the eye-movement of 16-month-old Swedish speaking children (N= 12) were analysed whenthey were tested on two made-up words. The words were either presented in neutral child-directedspeech or positive child-directed speech. This was done to see if the early word-learning is facilitatedby positive tone. The looking time was then analysed by a two-way ANOVA, and there was nosignificant difference between the two emotions. The conclusion drawn was that the hypothesis, thatthe looking time of the children that presented with positive child-directed speech would be longer,could not be confirmed nor rejected due to problems with collecting data and data analysis. Prior tofuture studies it is recommended to expand the number of participants, as well as examine othervariables that may affect early word learning.

This thesis investigates the use of the pragmatic particles (PPs) 'enfin' and 'écoute' in French film dialogue, and their translations in British English subtitles. Using a corpus of nine films and eight episodes drawn from two television series – all released in the UK between 2005 and 2015, and equating to approximately twenty-two hours – the study identifies tokens across a much wider range of contexts than has previously been possible using traditional corpora. The main contribution is an analysis of PP functions. The results for 'enfin' show a different functional distribution of the particle to other corpora, with corrective 'enfin' occurring significantly less frequently. The relatively large number of tokens of performative and emotional (or affective) 'enfin' allows for an elaboration of these two categories, and a tendency is observed for 'enfin' to appear as an apparent disagreement mitigator in discussions between peers. With regard to 'écoute', it is argued that écoute1 functions as a face-threat mitigator in unequal relationships and écoute2 as an FTA, although the particle is multifunctional and some tokens exhibit characteristics of both categories. Attention is given to combinations of 'enfin' and 'écoute' with other particles: while there is a clear tendency for disagreement-mitigating 'enfin' to co-occur with 'mais', and for the precision and restrictive subcategories of the corrective to co-occur with 'je veux dire', other previously documented combinations ('enfin bon' and 'ben écoute') are not frequently occurring in the present corpus. The thesis also makes a significant contribution to the field of Audiovisual Translation (AVT). The English subtitles show high rates of omission for both particles consistent with previous research, with disagreement-mitigating 'enfin' particularly vulnerable to omission. However, the analysis reveals a surprising pattern regarding 'écoute': a clear division of labour between ‘look’ (used to translate more confrontational tokens) and ‘listen’ (more conciliatory and socially distant). The study includes an experimental analysis of the subtitles relative to their character limits, demonstrating a potential new approach for researchers wishing to investigate the impact of various subtitling constraints.