Comme toutes modulations multiporteuses, l'OFDM souffre d'une forte variation d'amplitudes qui se traduit par un PAPR élevé. Cette caractéristique de l'OFDM la rend très sensible aux non-linéarités de l'amplificateur de puissance. Pour faire face à cette problématique, on peut surdimensionner l'amplificateur de puissance (solution non efficace en terme de rendement énergétique), linéariser l'amplificateur via les techniques de pré-distorsions, ou réduire le PAPR du signal avant amplification. L'objectif de cette thèse s'inscrit dans cette dernière thématique et plus particulièrement sur les techniques dites d'ajout de signal.Dans cette thèse, après une étude sur l'état de l'art des techniques de réduction du PAPR et en particulier les techniques dites d'ajout de signal, nous avons développé et proposé de nouvelles techniques de réduction du PAPR. Ces contributions s'articulent principalement autour des techniques de Clipping et de la Tone Reservation. / One of the main drawbacks of the OFDM modulation scheme is its high Peak-To-Average Power variation (PAPR) which can induce poor power efficiency at the transmitter amplifier. The digital base band pre-distortion for linearisation of power amplifier and the PAPR mitigation are the most commonly used solution in order to deals with efficiency and linearisation at the high power amplifier. This thesis is focused on the PAPR mitigation solution, and particularly on the adding signal based techniques. The proposed solutions in this report are about improving the Tone Reservation method which is the most popular adding signal based technique for PAPR mitigation, and also the classical clipping method which is the most simple method (in terms of computational complexity) actually.

No description available.

This paper analyses the protection offered by Copyright to newspaper articles and, from here, it examines the ways in which the articles are used by press clipping companies. Also, the paper presents resolutions related to the use of links to web pages and its relation with possible Copyright law infractions. Finally, the paper analyses a legislative amendment on the subject, which took place in Spain. / El artículo analiza la protección que brinda el derecho de autora los artículos periodísticos. A partir de ello, examina las distintas formas en que los mismos son utilizados por las empresas que se dedican al servicio de press clipping. Asimismo, presenta resoluciones vinculadas al uso de enlaces de páginas web y su relación con posibles infracciones al derecho de autor. Finalmente, el trabajo analiza una modificación legislativa sobre el tema ocurrida en España.

Comme toutes modulations multiporteuses, l'OFDM souffre d'une forte variation d'amplitudes qui se traduit par un PAPR élevé. Cette caractéristique de l'OFDM la rend très sensible aux non-linéarités de l'amplificateur de puissance. Pour faire face à cette problématique, on peut surdimensionner l'amplificateur de puissance (solution non efficace en terme de rendement énergétique), linéariser l'amplificateur via les techniques de pré-distorsions, ou réduire le PAPR du signal avant amplification. L'objectif de cette thèse s'inscrit dans cette dernière thématique et plus particulièrement sur les techniques dites d'ajout de signal.Dans cette thèse, après une étude sur l'état de l'art des techniques de réduction du PAPR et en particulier les techniques dites d'ajout de signal, nous avons développé et proposé de nouvelles techniques de réduction du PAPR. Ces contributions s'articulent principalement autour des techniques de Clipping et de la Tone Reservation. / One of the main drawbacks of the OFDM modulation scheme is its high Peak-To-Average Power variation (PAPR) which can induce poor power efficiency at the transmitter amplifier. The digital base band pre-distortion for linearisation of power amplifier and the PAPR mitigation are the most commonly used solution in order to deals with efficiency and linearisation at the high power amplifier. This thesis is focused on the PAPR mitigation solution, and particularly on the adding signal based techniques. The proposed solutions in this report are about improving the Tone Reservation method which is the most popular adding signal based technique for PAPR mitigation, and also the classical clipping method which is the most simple method (in terms of computational complexity) actually.

Perennial ryegrass (Lolium perenne L.) is commonly overseeded into hybrid bermudagrass [Cynodon dactylon (L.) Pers. X C. transvaalensis Burtt Davy] turfs during autumn in the southern United States. Overseeding can provide a green, actively-growing turf throughout the winter dormancy period. Improved persistence of perennial ryegrass cultivars has increased management inputs during the spring transition period. Lower input turf systems that provide acceptable winter overseeding quality are preferred, and research aimed at evaluating alternative overseeding species are warranted. Grooming reel attachments allowing for threedimensional clipping management (3DCM) have become increasingly used by turf managers for reducing grain and thatch, but scientific information on best management practices and canopy effects of 3DCM-grooming are lacking. A field study was conducted at the Texas A&M Turfgrass Field Laboratory in College Station, TX (30.6191 degrees N, 96.3576 degrees W), to investigate the effects of overseeding using annual (Lolium multiflorum Lam.) and perennial ryegrasses on 3DCM-groomed and non-groomed fairway turfs of 'Tifway' hybrid bermudagrass, zoysiagrass [Zoysia matrella (L.) Merr. 'Cavalier'], and seashore paspalum (Paspalum vaginatum Sw. 'Sea Isle 1'). The study was arranged as a randomized complete block split-split-plot with three replications. Species whole main plots were split into three grooming intervals, which were further split into four overseeding treatments. Data were collected assessing visual turf quality, visual turf cover, leaf area index, clipping yield, shoot density, and biomass partitioning. Results indicate annual ryegrass alone and an annual/perennial ryegrass overseeding mix provided acceptable turf quality, but did not improve turf recovery over perennial ryegrass alone in 'Tifway' or 'Sea Isle 1' turfs. In 'Cavalier' turfs, summer quality was affected by overseeding treatment as follows: control > annual > annual/perennial > perennial. The overseeding tolerance of the warm-season turfgrasses was as follows: 'Sea Isle 1' > 'Tifway' > 'Cavalier'. Differences in canopy architecture of warm-season turfgrasses were related to the overseeding tolerance of each species and used to explain plant competition during the spring transition period. Grooming by 3DCM improved late-season turf quality and reduced scalping in 'Tifway'. Overseeding establishment and canopy architecture were not affected by 3DCM.

In computer graphics technique, the 3D graphic pipeline flow has two processing modules: Geometry module and Rendering module. The geometry module supports vertex coordinate transformation, vertex lighting computation, backface-culling, pre-clipping, and clipping functions. Clipping module clips the outside part of objects by view volume boundaries. Adding clipping module into geometry module will make 3D graphics pipeline flow more efficiency. Due to the sequential parsing nature of clipping, it causes the challenges to implement clipping function in hardware design. This paper implements a dual-path clipping engine placed after the Vertex Shader in geometry module and supports OpenGL-ES 2.0 specification. With the clipping engine, it reduces the unnecessary operations in 3D graphics pipeline flow and makes the performance efficient. The pipelined and shared hardware design is proposed to improve the area cost and throughput of the interpolation operation in clipping engine. The two vertices in/out clipping method is proposed in this paper. Users have more different choices of clipping algorithms for hardware implementation with respect to the performance and hardware limitation.

Η παρούσα μελέτη πραγματοποιήθηκε στα πλαίσια της διπλωματικής εργασίας «Ψηφιακός Επεξεργαστής και Γραφικά Υπολογιστών». Κατά τη διάρκεια αυτής της μελέτης είχαμε την ευκαιρία να προσεγγίσουμε και να κατανοήσουμε την διαδικασία που επιτελείται για την αναπαράσταση γραφικών στην οθόνη του υπολογιστή μας, του κινητού μας τηλεφώνου και κατ’ επέκταση να προτείνουμε νέες ιδέες και τεχνικές οι οποίες αποσκοπούν στην βελτίωση και αύξηση της αποδοτικότητας. Για το λόγο αυτό μελετώντας τους υπάρχοντες αλγόριθμους, καταλήξαμε στην πρόταση ενός νέου ο οποίος προορίζεται κυρίως για συσκευές απεικόνισης μικρού μεγέθους όπως τα κινητά τηλέφωνα και έχει ως βασικό σκοπό τη μείωση σύνθετων υπολογιστικών πράξεων και εξοικονόμηση ενέργειας. Στη παρούσα εργασία παρουσιάζεται η λειτουργία των υπαρχόντων αλγόριθμων καθώς και του προτεινόμενου. Πραγματοποιούνται συγκρίσεις μεταξύ αυτών προκειμένου να δούμε το ποσοστό βελτίωσης που υπεισέρχεται, ενώ αναπτύσσουμε και το υπόβαθρο για την υλοποίηση και εφαρμογή του προτεινόμενου αλγόριθμου στην πράξη. / -

Chromatin is the combination of DNA and proteins in the nucleus that is used to aid in the compaction of DNA. Histones are a group of proteins used to condense DNA by forming a complex (nucleosome) around which DNA wraps around; there are two of each type of histone in a nucleosome: H2A, H2B, H3 and H4. Once the DNA is wrapped around the histones, the genome is further compacted. A shortened, "clipped" version of histone H3 has been found in some organisms including yeasts, flies, mammalian stem cells, and the ciliated protozoan, Tetrahymena thermophila. In each organism, clipping occurs at a different site on the N-terminus, usually before an alanine residue. Clipping is important as it may affect other epigenetic modifications and gene regulation in cell differentiation, but the regulation of this histone proteolysis has remained largely unstudied. In Tetrahymena thermophila, approximately half of the histone H3 molecules are clipped between residues 6 and 7 on histone H3, solely in the transcriptionally silent micronucleus. The histones in the micronuclei are deacetylated, while histones in the macronuclei can be acetylated or deacetylated. It is hypothesized that the post-translational acetylation modification to the histone tails may inhibit histone H3 clipping. Immunoblot analyses were carried out with acetylated and deacetylated micronuclei, demonstrating an increase of clipping when acetylated. Additionally, mutations were created at lysine 9 upstream of the clip site on the histone H3 tails to mimic acetylation and deacetylation to study whether the modification of that site has a regulatory effect.

No description available.

Orientador: Tania Regina de Luca / Resumo: Esta pesquisa propôs-se a analisar o Esquadrão da Morte (EM) a partir de uma fonte bastante específica: o clipping organizado pela Editora Abril entre 1968 e 1985. Trata-se de um conjunto de recortes de jornais, acondicionados em pastas específicas, que deveriam servir de apoio para os jornalistas responsáveis pala fatura de Realidade, que teve curta duração, e Veja. O esforço, que envolveu a criação de um Departamento de Documentação (DEDOC) e considerável investimento de capitais, justificava-se frente à ausência de meios eletrônicos de busca. Tal prática era comum nas grandes revistas de informação semanal ao redor do mundo. Sobretudo a partir de 1968, ano do lançamento de Veja, o cuidado com o clipping foi redobrado. Há várias pastas dedicadas ao EM, que foram descritas e analisadas de forma sistemática. Assim, não se trata propriamente de estudar a milícia em si, mas a forma como ela foi representada nesse conjunto. Um segundo objetivo, mais difícil de ser atingido, tentou relacionar o conteúdo publicado em Veja com o material disponível no clipping. O acervo reunido no clipping da Abril foi doado para o Centro de Documentação e Apoio a Pesquisa (CEDAP), UNESP/Assis, em dezembro de 2011. A coleção completa das edições de Veja está disponível online, sendo que o CEDAP também possui um conjunto significativo de exemplares. / Abstract: This research aimed to analyze the Death Squad (EM) from a very specific source: the clipping organized by the Editora Abril between 1968 and 1985. These are a set of newspaper clippings, packed in specific folders, which should serve as support for the journalists responsible and for the Realidade invoice, and Veja. The effort, which involved the creation of a Documentation Department (DEDOC) and capital investment, is justified in the absence of electronic means of searching. Such a practice was common in major weekly news magazines around the world. Especially since 1968, the year of Veja's release, the care with clipping was redoubled. There are several dedicated EM folders that have been systematically described and analyzed. It is not exactly a matter of studying a militia itself, but how it was represented in this set. Another goal, more difficult to achieve, tried to report content published in See with material available in clipping. The collection gathered in the clipping of Abril was donated to the Research Support Documentation Center (CEDAP), UNESP / Assis, in December 2011. The complete collection of Veja editions is available online, and CEDAP also has a set significant number of copies. / Mestre