In the past, we could rely on technology scaling and new micro-architectural techniques to improve the performance of processors. Nowadays, both of these methods are reaching their limits. The primary concern in future architectures with billions of transistors on a chip and limited power budgets is power/energy efficiency. Full-custom design of application-specific cores can yield up to two orders of magnitude better power efficiency over conventional general-purpose cores. However, a tremendous design effort is required in integrating a new accelerator for each new application. In this dissertation, we present the design of specialized compute fabrics that maintain the efficiency of full custom hardware while providing enough flexibility to execute a whole class of coarse-grain operations. The broad vision is to develop integrated and specialized hardware/software solutions that are co-optimized and co-designed across all layers ranging from the basic hardware foundations all the way to the application programming support through standard linear algebra libraries. We try to address these issues specifically in the context of dense linear algebra applications. In the process, we pursue the main questions that architects will face while designing such accelerators. How broad is this class of applications that the accelerator can support? What are the limiting factors that prevent utilization of these accelerators on the chip? What is the maximum achievable performance/efficiency? Answering these questions requires expertise and careful codesign of the algorithms and the architecture to select the best possible components, datapaths, and data movement patterns resulting in a more efficient hardware-software codesign. In some cases, codesign reduces complexities that are imposed on the algorithm side due to the initial limitations in the architectures. We design a specialized Linear Algebra Processor (LAP) architecture and discuss the details of mapping of matrix-matrix multiplication onto it. We further verify the flexibility of our design for computing a broad class of linear algebra kernels. We conclude that this architecture can perform a broad range of matrix-matrix operations as complex as matrix factorizations, and even Fast Fourier Transforms (FFTs), while maintaining its ASIC level efficiency. We present a power-performance model that compares state-of-the-art CPUs and GPUs with our design. Our power-performance model reveals sources of inefficiencies in CPUs and GPUs. We demonstrate how to overcome such inefficiencies in the process of designing our LAP. As we progress through this dissertation, we introduce modifications of the original matrix-matrix multiplication engine to facilitate the mapping of more complex operations. We observe the resulting performance and efficiencies on the modified engine using our power estimation methodology. When compared to other conventional architectures for linear algebra applications and FFT, our LAP is over an order of magnitude better in terms of power efficiency. Based on our estimations, up to 55 and 25 GFLOPS/W single- and double-precision efficiencies are achievable on a single chip in standard 45nm technology. / text

Dans ce mémoire de thèse, nous développons d'abord des multiplications matricielles efficaces. Nous créons de nouveaux ordonnancements qui permettent de réduire la taille de la mémoire supplémentaire nécessaire lors d'une multiplication du type Winograd tout en gardant une bonne complexité, grâce au développement d'outils externes ad hoc (jeu de galets), à des calculs fins de complexité et à de nouveaux algorithmes hybrides. Nous utilisons ensuite des technologies parallèles (multicœurs et GPU) pour accélérer efficacement la multiplication entre matrice creuse et vecteur dense (SpMV), essentielles aux algorithmes dits /boîte noire/, et créons de nouveaux formats hybrides adéquats. Enfin, nous établissons des méthodes de /design/ générique orientées vers l'efficacité, notamment par conception par briques de base, et via des auto-optimisations. Nous proposons aussi des méthodes pour améliorer et standardiser la qualité du code de manière à pérenniser et rendre plus robuste le code produit. Cela permet de pérenniser de rendre plus robuste le code produit. Ces méthodes sont appliquées en particulier à la bibliothèque de calcul exact LinBox.

The effect of water ingress in two pebble bed high temperature gas-cooled reactors i.e. the PBMR-200 MWthermal and the PBMR-400 MWthermal were simulated and compared using the VSOP 99/05 suite of codes. To investigate the effect of this event on reactivity, power profiles and thermal neutron flux profiles, the addition of partial steam vapour pressures in stages up to 400 bar into the primary circuit for the PBMR-400 and up to 300 bar for the PBMR- 200 was simulated for both reactors. During the simulation, three scenarios were simulated, i.e. water ingress into the core only, water ingress into the reflectors only and water ingress into both the core and reflectors. The induced reactivity change effects were compared for these reactors. An in-depth analysis was also carried out to study the mechanisms that drive the reactivity changes for each reactor caused by water ingress into the fuel core only, the riser tubes in the reflectors only and ingress into both the fuel core and the riser tubes in the reflectors. The knowledge gained of these mechanisms and effects was used in order to propose design changes aimed at mitigating the reactivity increases, caused by realistic water ingress scenarios. Past results from simulations of water ingress into Pebble Bed Reactors were used to validate and verify the present simulation approach and results. The reactivity increase results for both reactors were in agreement with the German HTR-Modul calculations. / Thesis (MSc (Engineering Sciences in Nuclear Engineering))--North-West University, Potchefstroom Campus, 2013

The effect of water ingress in two pebble bed high temperature gas-cooled reactors i.e. the PBMR-200 MWthermal and the PBMR-400 MWthermal were simulated and compared using the VSOP 99/05 suite of codes. To investigate the effect of this event on reactivity, power profiles and thermal neutron flux profiles, the addition of partial steam vapour pressures in stages up to 400 bar into the primary circuit for the PBMR-400 and up to 300 bar for the PBMR- 200 was simulated for both reactors. During the simulation, three scenarios were simulated, i.e. water ingress into the core only, water ingress into the reflectors only and water ingress into both the core and reflectors. The induced reactivity change effects were compared for these reactors. An in-depth analysis was also carried out to study the mechanisms that drive the reactivity changes for each reactor caused by water ingress into the fuel core only, the riser tubes in the reflectors only and ingress into both the fuel core and the riser tubes in the reflectors. The knowledge gained of these mechanisms and effects was used in order to propose design changes aimed at mitigating the reactivity increases, caused by realistic water ingress scenarios. Past results from simulations of water ingress into Pebble Bed Reactors were used to validate and verify the present simulation approach and results. The reactivity increase results for both reactors were in agreement with the German HTR-Modul calculations. / Thesis (MSc (Engineering Sciences in Nuclear Engineering))--North-West University, Potchefstroom Campus, 2013

In this digital age, cryptography is largely built in computer hardware or software as discrete structures. One of the most useful of these structures is finite fields. In this thesis, we explore a variety of applications of the theory and applications of arithmetic and computation in finite fields in both the areas of cryptography and cryptanalysis. First, multiplication algorithms in finite extensions of prime fields are explored. A new algebraic description of implementing the subquadratic Karatsuba algorithm and its variants for extension field multiplication are presented. The use of cy- clotomic fields and Gauss periods in constructing suitable extensions of virtually all sizes for efficient arithmetic are described. These multiplication techniques are then applied on some previously proposed public key cryptosystem based on exten- sion fields. These include the trace-based cryptosystems such as XTR, and torus- based cryptosystems such as CEILIDH. Improvements to the cost of arithmetic were achieved in some constructions due to the capability of thorough optimisation using the algebraic description. Then, for symmetric key systems, the focus is on algebraic analysis and attacks of stream ciphers. Different techniques of computing solutions to an arbitrary system of boolean equations were considered, and a method of analysing and simplifying the system using truth tables and graph theory have been investigated. Algebraic analyses were performed on stream ciphers based on linear feedback shift registers where clock control mechanisms are employed, a category of ciphers that have not been previously analysed before using this method. The results are successful algebraic attacks on various clock-controlled generators and cascade generators, and a full algebraic analyses for the eSTREAM cipher candidate Pomaranch. Some weaknesses in the filter functions used in Pomaranch have also been found. Finally, some non-traditional algebraic analysis of stream ciphers are presented. An algebraic analysis on the word-based RC4 family of stream ciphers is performed by constructing algebraic expressions for each of the operations involved, and it is concluded that each of these operations are significant in contributing to the overall security of the system. As far as we know, this is the first algebraic analysis on a stream cipher that is not based on linear feedback shift registers. The possibility of using binary extension fields and quotient rings for algebraic analysis of stream ciphers based on linear feedback shift registers are then investigated. Feasible algebraic attacks for generators with nonlinear filters are obtained and algebraic analyses for more complicated generators with multiple registers are presented. This new form of algebraic analysis may prove useful and thereby complement the traditional algebraic attacks. This thesis concludes with some future directions that can be taken and some open questions. Arithmetic and computation in finite fields will certainly be an important area for ongoing research as we are confronted with new developments in theory and exponentially growing computer power.

Cryptographic protocols are implemented in hardware to ensure low-area, high speed and reduced power consumption especially for mobile devices. Elliptic Curve Cryptography (ECC) is the most commonly used public-key cryptosystem and its performance depends heavily on efficient finite field arithmetic hardware. Finding the multiplicative inverse (inversion) is the most expensive finite field operation in ECC. The two predominant algorithms for computing finite field inversion are Fermat’s Little Theorem (FLT) and Extended Euclidean Algorithm (EEA). EEA is reported to be the most efficient inversion algorithm in terms of performance and power consumption. This dissertation presents a new reformulation of EEA algorithm, which allows for speedup and optimization techniques such as concurrency and resource sharing. Modular arithmetic operations over GF(p) are introduced for small values of p, observing interesting figures, particularly for modular division. Whereas, polynomial arithmetic operations over GF(pm) are discussed adequately in order to examine the potential for processes concurrency. In particular, polynomial division and multiplication are revisited in order to derive their iterative equations, which are suitable for systolic array implementation. Consequently, several designs are proposed for each individual process and their complexities are analyzed and compared. Subsequently, a concurrent divider/multiplier-accumulator is developed, while the resulting systolic architecture is utilized to build the EEA-based inverter. The processing elements of our systolic architectures are created accordingly, and enhanced to accommodate data management throughout our reformulated EEA algorithm. Meanwhile, accurate models for the complexity analysis of the proposed inverters are developed. Finally, a novel, fast, and compact inverter over binary fields is proposed and implemented on FPGA. The proposed design outperforms the reported inverters in terms of area and speed. Correspondingly, an EEA-based inverter over ternary fields is built, showing the lowest area-time complexity among the reported inverters. / Graduate

Orientador: Prof. Dr. Francisco José Brabo Bezerra / Dissertação (mestrado) - Universidade Federal do ABC, Programa De Pós-Graduação em Ensino, História, Filosofia das Ciências e Matemática, 2016. / A presente pesquisa teve como objetivo a organização do ensino da multiplicação a partir do conceito de medida para os anos iniciais do Ensino Fundamental. A questão que norteia a pesquisa é: Como o professor pode organizar o ensino da multiplicação para os anos iniciais do Ensino Fundamental tendo o conceito de medida como instrumento mediador? Estudamos a multiplicação como isomorfismo de medida, porque transcende o modelo tradicional ao reconhecê-la como uma relação quaternária na qual estão associados outros conceitos matemáticos. Este olhar da multiplicação facilitou o estudo das relações do conceito de multiplicação com as medidas. Tal compreensão possibilitou a elaboração de situações desencadeadoras de aprendizagem nas quais as medidas foram as protagonistas e o pensar multiplicativamente o objetivo a ser alcançado. Elas foram compartilhadas num curso de extensão com professores dos anos iniciais do Ensino Fundamental de uma mesma escola, desencadeando a organização do ensino da multiplicação para os diferentes níveis. Temos por hipótese que levar os estudantes pelo caminho dos nexos conceituais do medir possibilita o entendimento das etapas do pensar multiplicativamente. Após o trabalho em sala, se deu um momento de discussão e reflexão com dois objetivos: o primeiro, constituir atividades de ensino a partir dos relatos de experiência dos professores com relação à Atividade de Ensino e à Atividade de Aprendizagem, e o segundo, refletir sobre como o conceito de medida pode ser um instrumento mediador para o ensino da multiplicação. Concluímos que as situações desencadeadoras de aprendizagem desenvolvidas com/para os professores possibilitaram ressignificar o ensino da multiplicação, e apresentou um modo geral de ação para organizar o ensino da multiplicação a partir das medidas. / The aim of the current research was to organize the teaching of multiplication in the first years of elementary school by means of the measurement concept. The main question of the research is: How can the teacher organize the multiplication teaching in the first years of elementary school by taking into account the measurement concept as a mediating instrument? We studied the multiplication as a measure isomorphism, because it transcends the traditional model when recognizing it as a quaternary relationship, in which other mathematical concepts are associated. This multiplication approach made easier the study of the relationship between the multiplication concept and the measures. This comprehension allowed the elaboration of trigger-learning situations such that the measurements were the protagonists, and thinking multiplicatively was the aim to be reached. These situations were shared in an extension course with teachers of elementary school from the same school, triggering the organization of multiplication teaching for different levels. In our hypothesis, leading the students for the paths of the conceptual nexuses of measuring allows the understanding of the stages of thinking multiplicatively. After working in the classroom, we gave the teachers time to discuss and reflect with two objectives: the first one was to construct teaching activities from their reports of experience in relation to the teaching and learning activities, and the second one was to think about how the concept of measure can be a mediator instrument for the multiplication teaching. We conclude that the trigger-learning situations developed with/for the teachers reached two main points: they made possible to give another meaning to the multiplication teaching and presented a general way of action for organizing the multiplication teaching by means of measures.

The Forest Sector has an accomplishment to attend the demand for noble wood products, usually get from native Brazilian species as louro-pardo. Therefore, propagation studies of native species are necessary to produce high quality plants for commercial exploitation and to reduce deforestation pressure over remained populations of native species. The objective of this study was to develop protocols of establishment in vitro and propagation of louro-pardo. Time of seed imbibition and disinfection protocols were studied for in vitro seedling establishment. Seeds were imbibed in distilled and autoclaved water for 0, 24, 48, 72, 96 and 120 h. Seeds were immersed in a sodium hypochlorite solution of 5% for 30 min, submitted to tegument excision and immersed in a alcohol solution of 70% for 30 s. Disinfection was done in sodium hypochlorite solutions of 2 and 5% for 0, 5, 10 15 and 20 min. Seeds without tegument were then inoculated in medium culture for germination. Percentages of disinfection and germination and mean germination time were evaluated. Seedling growth was quantified in 1/2MS and WPM culture mediums. Number of emerged leaves and primary roots and length of shoots and primary roots were evaluated at 7, 14, 21 and 28 days after inoculation. The addition to the WPM culture medium of 0; 0.05; 0.10; 0.15 or 0.20 mg L-1 of 6-benzilaminopurin (BAP), naphthalene acetic acid (NAA) or gibberellic acid (GA3) and the combination of 0 or 0.05 mg L-1 of NAA with 0; 0.10 or 0.20 mg L-1 of GA3 were tested for propagation. At 30 days after inoculation, number of internodes and leaves and plantlet height were evaluated. Plantlets of seminal origin were also excised below or above the first true leaf and the microstumps maintained in vitro with liquid WPM added to the original medium to increase multiplication rate. Number of sprouts and internodes per microstump were evaluated at 21 days after first and second excision. Minicuttings from 2.5 to 4, 4.01 to 5.5 and 5.51 to 7 cm were treated with 0 or 1000 mg L-1 of indol butyric acid (IBA) by basal immersion for 10 s. Survival and rutting percentage and callus formation were evaluated at 60 days after treatment. Imbibition of louro-pardo seeds until 24 hours made easy tegument excision without affecting disinfection and germination. Immersion of seeds with tegument in a sodium hypochlorite solution of 5% for 30 min, tegument excision and immersion in a alcohol solution of 70% for 30 s are enough for an acceptable production of in vitro aseptic seedlings. Louro-pardo seedlings grow satisfactorily in a WPM culture medium without growth regulators. The addition of growth regulators either isolated or combined to the WPM medium did not increase in vitro propagation. Maintaining microstump increased the in vitro multiplication rate in 1.75 fold. Minicuttings of louro-pardo from 2.5 to 5.5 cm showed high survival percentages, but they did not root. Protocols of plantlet acclimatization and clonal propagation by minicuttings should be developed to produce high genetic and physiological quality of louro-pardo plants / O setor florestal hoje enfrenta um grande desafio, atender à demanda por produtos madeireiros nobres, abastecido especialmente por espécies nativas brasileiras, dentre elas o louro-pardo. Nesse sentido, estudos de propagação que contemplem espécies nativas são necessários para garantir a produção de mudas de qualidade para plantios comerciais, reduzindo a pressão sobre as matas remanescentes. O objetivo deste estudo foi desenvolver protocolos de estabelecimento in vitro e de propagação de louro-pardo. Para o estabelecimento in vitro, estudou-se o efeito do tempo de embebição e de diferentes protocolos de desinfestação das sementes. A embebiçao se fez em água destilada e autoclavada por 0, 24, 48, 72, 96 e 120 h. Para a desinfestação, testou-se a imersão em solução de hipoclorito de sódio a 2 e 5%, por 0, 5, 10, 15 e 20 min. após 30 min de imersão em hipoclorito de sódio a 5%, retirada do tegumento e imersão em álcool etílico 70% por 30 s. Sementes sem tegumento foram inoculadas em meio de cultura para germinação. Foram avaliadas as porcentagens de desinfestação e germinação e o tempo médio de germinação. O crescimento de explantes de louro-pardo foi quantificado nos meios de cultura 1/2MS e WPM, pelo número de folhas e raízes primárias emitidas e comprimento da parte aérea e das raízes primárias, aos 7, 14, 21 e 28 dias após a inoculação. Para a multiplicação, foram testadas a adição ao meio de cultura WPM de 6-benzilaminopurina (BAP), ácido naftaleno acético (ANA) ou ácido giberélico (GA3) nas concentrações de 0; 0,05; 0,10; 0,15 ou 0,20 mg L-1 e a combinação de 0 ou 0,05 mg L-1 de ANA com 0; 0,10 ou 0,20 mg L-1 de GA3. Foram avaliados o número de folhas e de entrenós e a altura das plântulas aos 30 dias de cultivo. Plântulas fornecedoras de segmentos nodais e ápices caulinares foram reidratadas com meio WPM líquido e mantidas in vitro como microcepas, para aumentar a taxa de multiplicação. Aos 21 dias após o primeiro e o segundo corte foi avaliado o número de brotações adventícias e de entrenós por microcepa. Miniestacas de 2,5 a 4; 4,01 a 5,5 e 5,51 a 7 cm foram submetidas à aplicação de 0 ou 1000 mg L-1 de ácido indol butírico (AIB) por 10 s na base. Foram avaliadas as porcentagens de sobrevivência, enraizamento e formação de calos aos 60 dias. A embebição das sementes de louro-pardo por até 24 h favorece a retirada do tegumento sem afetar a desinfestação e germinação. A imersão das sementes com tegumento em NaOCl 5% por 30 min, retirada do tegumento e a imersão das sementes sem tegumento em solução de álcool etílico 70% por 30 s foram suficientes para a produção in vitro de plântulas assépticas. Plântulas de louro-pardo apresentaram melhor crescimento em meio de cultura WPM, sem a adição de reguladores de crescimento. A adição isolada ou combinada de reguladores de crescimento não aumentou a taxa de multiplicação in vitro. A manutenção de microcepas aumentou a taxa de multiplicação in vitro em até 1,75 vezes. Miniestacas de louro-pardo de 2,5 a 5,5 cm de comprimento apresentaram altos índices de sobrevivência, porém não enraizaram

Made available in DSpace on 2014-06-11T19:35:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-05-19Bitstream added on 2014-06-13T20:26:30Z : No. of bitstreams: 1 faria_ga_dr_ilha_prot.pdf: 2915526 bytes, checksum: 6eed63992f54372dba74ee2762c7ab68 (MD5) / Estudos preliminares referentes ao tipo de explante, meio de cultura são necessários para se definir protocolos de estabelecimento, desenvolvimento, multiplicação e conservação in vitro, bem como garantir a fidelidade na resposta morfogênica. A determinação do número ideal de repetições e do tamanho ótimo de parcelas experimentais é uma das maneiras de se aumentar a precisão experimental e, conseqüentemente, maximizar as informações obtidas em um experimento. Este trabalho teve por objetivo a determinação do tamanho ótimo de parcelas em experimentos in vitro nas etapas de estabelecimento, desenvolvimento, multiplicação e conservação de Passiflora sp. Foram conduzidos sete experimentos, com diversos ensaios de uniformidade com as espécies Passiflora giberti N.E. Brown., P. edulis Sims f. edulis, e P. laurifolia L.. Foram simulados diversos tamanhos e formas de parcelas, em que cada frasco com um explante foi considerado como uma unidade básica (parcela), os quais foram combinados formando parcelas com até 10, 25 e 50 frasco com um explante por unidade básica, em função do tipo de experimento. Para a estimação do tamanho ótimo de parcelas empregou-se o método da máxima curvatura modificado. De acordo com os resultados obtidos para experimentos in vitro com a espécie P. giberti N. E. Brown., o tamanho ótimo de parcelas recomendado é o de 15 frasco com um explante para experimentos de estabelecimento, 10 frasco com um explante por parcela para experimentos com conservação e 13 frasco com um explante para experimentos com desenvolvimento. Para a espécie P. edulis Sims f. edulis, o tamanho ótimo de parcelas recomendado é o de 11 frasco com um explante para experimentos de estabelecimento e 26 frasco com um explante para experimentos de multiplicação. Para a espécie P. laurifolia L., o tamanho ótimo de parcela deve ser de 9 frasco com um explante para... / Preliminary studies concerning to explant type and culture medium are necessary to define establishment, development multiplication and in vitro conservation protocols, as well to guarantee fidelity in morphogenic response. One of the ways to increase experimental precision is to determinate the ideal number of repetitions and the optimal size of plots and maximize informations obtained in a experiment. This work aimed to determinate optimal size of plots in in vitro experiments for establishment, development, multiplication e conservation of Passiflora sp. Seven experiments were made, with several uniformity essays with Passiflora giberti N.E. Brown., P. edulis Sims f. edulis, e P. laurifolia L. species. Various sizes and plot forms were simulated, where as each bottle with a explain was considered as the basic unit till 10, 25 e 50 bottles with a explant by basic unit. Modified maximum curvature method was employed to estimate the optimal size of plots. According to results in vitro experiments with P. giberti N. E. Brown. species, optimal size of plots recommended is 15 bottles with a explant in establishment experiments, 10 bottles with a explant by plot in conservation experiments and 13 bottles with a explant in development experiments. The optimal size of plots recommended to P. edulis Sims f. edulis species is 11 bottles with a explant in establishment experiments and 26 bottles with a explant in multiplication experiments. The optimal size of plots to P. laurifolia L. species is 9 bottles with a explant in establishment experiments and 34 bottles with a explant in multiplication experiments, considering available variables in all experiments. The results obtained can subsidize with Passiflora culture in vitro experiments under different conditions

Assim nasce uma Igreja : A multiplicação das Comunidades Cristãs Independentes no Município da Serra, Estado do Espírito Santo é um trabalho que visa identificar os fatores que têm desencadeado o nascimento de novas Igrejas Cristãs, sem vínculo com comunidades históricas, no município da Serra, bem como a repercussão deste fenômeno nas Igrejas Protestantes Históricas, notadamente nas Igrejas Batistas, tanto em seus benefícios como nos prejuízos. No primeiro capítulo, situa-se a pesquisa geográfica e teoricamente, através de um mapeamento religioso do município da Serra e uma apresentação da tipologia utilizada no trabalho. O segundo capítulo traz uma síntese histórica, mostrando como as Igrejas Cristãs nasceram, desde o período do Novo Testamento até os dias atuais, com ênfase nas Igrejas do Cristianismo Primitivo, Grande Cisma, Movimento Reformador do Século XVI e Movimento Pentecostal. No terceiro capítulo são identificados os fatores externos e internos que tem desencadeado o nascimento de novas igrejas. O quarto capítulo apresenta os benefícios e os prejuízos que a fragmentação do Cristianismo produz para as Igrejas Cristãs Históricas e para o Reino de Deus. / Thus was born a church: the rise of the Christian Independent communities in the city of Serra, Espírito Santo is a work that aims to identify the factors that has triggered the birth of new Christian churches, not related to historical communities in the municipality of Serra, as well as the impact of this phenomenon in Historical Protestant Churches, especially in Baptist Churches, in both its benefits and the losses. In the first chapter, the geographical search is located and theoretically, through a mapping of the religious city of Serra and a presentation of the typology used in this work. The second chapter provides a brief history, showing how the Christian churches were born from the New Testament period to the present, with emphasis on early Christianity Churches, Great Schism, the Reform Movement of the XVI century, and in the Pentecostal movement. The third chapter identifies the external and internal factors that have triggered the birth of new churches. The fourth chapter presents the benefits and losses that the fragmentation of Christianity creates to the Historic Christian Churches and the Kingdom of God.