Le défi primaire dans le développement matériel de la cryptographie moderne est de faire des implémentations optimales en ressources, et rapide, en garantissant une résistance contre les attaques. Cette recherche porte sur les implémentations pratiques des opérations de cryptographie basées sur la cryptographie à clé publique dans les corps finis. Durant cette thèse nous avons proposé des composants matériels de base. L'arithmétique des corps finis constitue le noyau de la cryptographie à clé publique comme RSA, ECC ou une cryptographie basée sur le couplage. Nous avons proposé dans cette thèse des architectures du calcul arithmétique haute performance pour implémenter les primitives de cryptographie asymétrique. Les composants décrits dans notre travail ont été implémentés dans des Field Programmable Gate Array platforms (FPGA) de Xilinx. Nous avons utilisé le VHDL pour développer nos composants et nos architectures. Nos résultats présentent des performances en ressources et en vitesse jamais égalées auparavant dans la littérature publique sur ce type de technologie. La particularité de ces architectures est l'utilisation de l'architecture systolique pour développer une multiplication modulaire. Cette thèse traite la mise en œuvre matérielle efficace de la méthode CIOS (Coarsely Integrated Operand Scanning) de la multiplication modulaire de Montgomery combinée avec une architecture systolique efficace. D'après nos connaissances, c'est la première implémentation d'une telle conception. Nos architectures visaient à réduire le nombre de cycles d'horloge de la multiplication modulaire. Les résultats d'implémentation des algorithmes CIOS se concentrent sur différents niveaux de sécurité utiles en cryptographie. Cette architecture a été conçue pour utiliser le DSP48 flexible sur les FPGA de Xilinx. Nos architectures sont évolutives et dépendent uniquement du nombre et de la taille des mots. Par exemple, nous fournissons des résultats d'implémentation pour des longs mots de 8, 16, 32 et 64 bits en 33, 66, 132 et 264 cycles d'horloge. Nous décrivons également un design pour calculer une inversion et/ou une division dans Fp. L'inversion peut être utilisée dans les systèmes de la cryptographie de courbe elliptique et de la cryptographie basée sur le couplage. / The primary challenge in the hardware development of the modern cryptography is to make an optimal implementations in resources and speed, with guaranteeing a resistance against attacks. This research focuses on practical implementations of cryptographic operations based on public key cryptography in finite fields. During this thesis we proposed basic hardware components. Finite field arithmetic is the core of public key cryptography such as RSA, ECC, or pairing-based cryptography. We proposed in this thesis a high-performance architectures of arithmetic calculation to implement asymmetric cryptographic primitives. The components described in this thesis have been implemented in Xlinx Field Programmable Gate Array Platforms (FPGAs). We used the VHDL to devolve our components and architectures. Our results show a performance and speed never presented before in the literature on this type of technology. The particularity of these architectures is the use of systolic architecture to develop a modular multiplication. This thesis deals with the effective physical implementation of the Coarsely Integrated Operand Scanning (CIOS) method of Montgomery's modular multiplication combined with an effective systolic architecture. According to our knowledge, this is the first implementation of such a design. Our architectures were aimed at reducing the number of clock cycles of modular multiplication. The implementation results of the CIOS algorithms focus on different levels of security useful in cryptography. This architecture was designed to use the flexible DSP48 on Xilinx FPGAs. Our architectures are scalable and depend only on the number and size of the words. For instance, we provide implementation results for 8, 16, 32, and 64 bit long words in 33, 66, 132, and 264 clock cycles. We describe also a design to compute an inversion in Fp as well as division. Inversion can be used in Elliptic Curve Cryptography systems and pairing-based cryptography.

Made available in DSpace on 2014-06-11T19:33:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-12Bitstream added on 2014-06-13T21:06:46Z : No. of bitstreams: 1 silva_ar_dr_jabo.pdf: 1487847 bytes, checksum: 2afc8af98e0701cb3f7670e55d76e07d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A reação de ‘HPC 7 B’, ‘Lady Rosetta’, ‘Ágata’, ‘Cupido’, ‘Monalisa’, ‘Panda’, ‘Itararé’, ‘Asterix’, ‘Capiro’, ‘Atlantic’, ‘Mayor’ e ‘Canchan’ a Meloidogyne incognita, M. javanica e M. mayaguensis foi avaliada em casa de vegetação. Um novo método in vitro para testar a reação de genótipos de batata à M. javanica foi desenvolvido utilizando mini-tubérculos enraizados. Avaliou-se a reação de ‘HPC 1 B’, ‘HPC 6 B’, ‘HPC 7 B’, ‘Ágata’ e ‘Cupido’ a M. javanica e a produção de inóculo em função da densidade do inóculo e do período de incubação. Coletaram-se 168 amostras de tubérculos nas principais regiões produtoras do País para levantar os fitonematóides associados e caracterizar os sintomas. Os genótipos avaliados hospedam M. incognita, M. javanica e M. mayaguensis. A reação in vitro confirma esses resultados. Minitubérculos suportam os fitonematóides por até 180 dias, com produção média máxima estimada em 15.990 ovos por frasco. Foram encontradas Meloidogyne arenaria no Sul de Minas e Rio Grande do Sul (3,5% das amostras), M. incognita em 10% (exceto no Sul do País) e M. javanica em todas as regiões amostradas (50%), causando como principal sintoma em tubérculo e raízes, caroços protuberantes, que dão a superfície aspecto áspero. Identificou-se também Pratylenchus brachyurus em 40% das amostras (exceto no Rio Grande do Sul), P. coffeae em 2,4% (Triângulo Mineiro, Sul de Minas e São Paulo) e P. penetrans (3%), em São Paulo, causando lesões em forma de pontos necróticos, deprimidos, na superfície do tubérculo. Encontrou-se Helicotylenchus dihystera em todas as regiões amostradas (49%). Conquanto esse fitonematóide seja um ectoparasito migrador, as amostras tenham sido constituídas de tubérculos lavados e nenhum sintoma específico foi observado, essa alta freqüência... / The reaction of ‘HPC 7 B’, ‘Lady Rosetta’, ‘Ágata’, ‘Cupido’, ‘Monalisa’, ‘Panda’, ‘Itararé’, ‘Asterix’, ‘Capiro’, ‘Atlantic’, ‘Mayor’ and ‘Canchan’ to Meloidogyne incognita, M. javanica and M. mayaguensis was evaluated at greenhouse. A new in vitro method to test the reaction of these genotypes to M. javanica was developed using rooted mini-tubers. Were evaluated the reaction of ‘HPC 1 B’, ‘HPC 6 B’, ‘HPC 7 B’, ‘Ágata’ and ‘Cupido’ to M. javanica and the inoculum production in terms of density of inoculum and the period of incubation. Were collected 168 samples from symptomatic tubers in the Brazil main producing regions (Goiás, Minas Gerais, Paraná, Rio Grande do Sul and São Paulo), to raise the species of plant parasitic nematodes associated with the crop and to characterize the symptoms. All the genotypes host M. incognita, M. javanica and M. mayaguensis. The in vitro reaction confirms these results. Mini-tubers support the plant parasitic nematodes for up to 180 days, with maximum production of 15,990 eggs per pot. Meloidogyne arenaria was found in Sul de Minas and Rio Grande do Sul (3.5% of samples), M. incognita by 10% (except in the Sul) and M. javanica in all regions sampled (50%), causing knot a major symptom in tuber and roots, giving the surface looks rough. It was also Pratylenchus brachyurus in 40% of the samples (except in Rio Grande do Sul), P. coffeae at 2.4% (Triângulo Mineiro, Sul de Minas and São Paulo) and P. penetrans (3%), in São Paulo, causing lesions in the form of pointed depressed necrotic on the surface of the tuber. Helicotylenchus dihystera was found in all regions sampled (49%). Since the samples consist of tubers have been washed, this plant parasitic nematode is a migratory ectoparasite and no specific symptom was observed, this high frequency requires a more accurate study... (Complete abstract click electronic access below)

Esta dissertação tem como objetivo salientar a utilidade e importância de cálculos matriciais no ensino médio. Para tanto, foram estudados alguns tópicos que descrevem situações que necessitam de recursos gerados por operações matriciais. Foi observado que esses tópicos apresentam situações que evidenciam a utilidade da multiplicação de matrizes não somente no desenvolvimento teórico, mas também nas aplicações de matrizes, e têm potencial para serem abordados no ensino médio / The aim is this work is to stress on the use of algebraic operations with matrices in the mathematics teaching for secondary school students. For this purpose, we studied some topics that require algebraic operations with matrices. It was observed that these topics reveal circumstances in which the matrix multiplication is not only useful in the theoretical development but also in the applications. In addition, the studied showed that these themes have potential to be considered in the secondary school

This thesis aims to prove the following statement, where the Weierstrass p-function has algebraic invariants and complex multiplication by Q(alpha): "If beta_1,..., beta_n are algebraic numbers which are linearly independent over Q(alpha), then p(beta_1),...,p(beta_n) are algebraically independent over Q." This was proven by Philippon in 1983, and the proof in this thesis follows his ideas. The difference lies in the strength of the tools used, allowing certain arguments to be simplified. This thesis shows that the above result is equivalent to imposing the restriction (beta_1,...,beta_n)=(1,beta,...,beta^{n-1}), where n=[Q(alpha,beta):Q(alpha)]. The core of the proof consists of developing height estimates, constructing representations for morphisms between products of elliptic curves, and finding height and degree estimates on large families of polynomials which are small at a point in Q(alpha,beta,g_2,g_3)(p(1),p'(1),...,p(beta^{n-1}),p'(beta^{n-1})). An application of Philippon's zero estimate (1986) and his criterion of algebraic independence (1984) is then used to obtain the main result.

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The purpose of this action research study was to evaluate my own practice of teaching basic multiplication facts to fourth graders. I wanted to see how focusing my instruction on strategies would help my students develop proficiency in basic multiplication facts. I chose this topic because Florida was in the process of shifting to new standards that encourage teaching for deeper meaning. I hoped this research would give my students the opportunity to make sense of multiplication on a deeper level, while giving me insight into how students learn multiplication. Through this study, I learned that students initially find multiplication to be very difficult, but they can solve basic facts with ease when using strategies. Students did become more proficient with basic multiplication facts, and they were also able to apply basic fact strategies to extended facts and other multidigit multiplication problems. There is a limited amount of research on how students acquire basic multiplication fact proficiency; however, this study offers more insight to teachers and the research community.

The optimal implementation of matrix multiplication on modern computer architectures is of great importance for scientific and engineering applications. However, achieving the optimal performance for matrix multiplication has been continuously challenged both by the ever-widening performance gap between the processor and memory hierarchy and the introduction of new architectural features in modern architectures. The conventional way of dealing with these challenges benefits significantly from the blocking algorithm, which improves the data locality in the cache memory, and from the highly tuned inner kernel routines, which in turn exploit the architectural aspects on the specific processor to deliver near peak performance. A state-of-art improvement of the blocking algorithm is the self-tuning approach that utilizes "heroic" combinatorial optimization of parameters spaces. Other recent research approaches include the approach that explicitly blocks for the TLB (Translation Lookaside Buffer) and the hierarchical formulation that employs memoryriendly Morton Ordering (a spaceilling curve methodology). This thesis compares and contrasts the TLB-blocking-based and Morton-Order-based methods for dense matrix multiplication, and offers a qualitative model to explain the performance behavior. Comparisons to the performance of self-tuning library and the "vendor" library are also offered for the Alpha architecture. The practical benchmark experiments demonstrate that neither conventional blocking-based implementations nor the self-tuning libraries are optimal to achieve consistent high performance in dense matrix multiplication of relatively large square matrix size. Instead, architectural constraints and issues evidently restrict the critical path and options available for optimal performance, so that the relatively simple strategy and framework presented in this study offers higher and flatter overall performance. Interestingly, maximal inner kernel efficiency is not a guarantee of global minimal multiplication time. Also, efficient and flat performance is possible at all problem sizes that fit in main memory, rather than "jagged" performance curves often observed in blocking and self-tuned blocking libraries.

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A new beta-ray detector using the Thick Gas Electron Multiplier (THGEM) technology is presented. Traditional proportional counters have been considered the standard for many decades for radiation contamination monitoring. However, it has always been challenging to detect low energy beta-emitters such as 3H and 14C. In order to extend the low energy cut-off of these beta particles, it is important to keep the electron multiplication gain as high as possible. To accomplish this goal, we have developed a new gaseous beta-ray detector using THGEMs. Founded on previous THGEM avalanche simulations [1] and predecessor detectors, a novel prototype THGEM beta-ray detector was designed and fabricated. Its signal performance, effective gain and gain stability were comprehensively studied for single and double-THGEM configurations using an alpha source. The first time THGEM detector response to beta-rays was observed for various operating conditions and compared with Monte Carlo N-Particle Transport 6 (MCNP6) Monte Carlo simulations. / Thesis / Master of Science (MSc)