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  • 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.
11

A Combined Circuit for Multiplication and Inversion in ${rm GF}(2^{m})$

Kobayashi, Katsuki, Takagi, Naofumi, 高木, 直史 11 1900 (has links)
No description available.
12

Implementation of RSA Cryptosystem for Next Generation RFID Tags

Dighe, Ashish Arun 29 March 2011 (has links)
This thesis addresses concepts of implementing a RSA cryptosystem on a passive RFID tag. With a limited number of public key cryptosystems on passive RFID platforms, the proposed algorithm makes use of Montgomery multiplication primitives to reduce the amount of computation required on the power constrained tag therefore making the proposition viable. Public key cryptography is being suggested for next generation RFID systems to reduce the number of possible attack vectors native to this type of technology. By estimating the area, power and time constraints of the RFID platform, it was determined that the area constraint was the critical variable in determining the maximum implementable security variable. Although the application of this algorithm has been targeted for passive HF RFID platforms, the algorithm could be used in other low power, sized constrained applications.
13

Apport de l'ordinateur à l'apprentissage des écritures multiplicatives au cours élémentaire /

Butlen, Denis. January 1985 (has links)
Th. 3e cycle--Didactique des mathématiques--Paris VII, 1985. / Notes bibliogr.
14

Spectroscopie THz de molécules atmosphériques : application à l'étude de composés organiques volatils / THz spectroscopy of atmospheric molecules : application to the studies of the volatile organic compounds

Zakharenko, Olena 01 March 2016 (has links)
Nous présentons des travaux de spectroscopie moléculaire, avec des développements expérimentaux et des analyses à haute résolution de spectres de molécules atmosphériques. Nous avons mis en place et testé une nouvelle chaine de multiplication de fréquences destinée à étendre la gamme du spectromètre THz du laboratoire PhLAM. Les principaux paramètres du spectromètre, tels que la sensibilité, la précision des mesures et la composition harmonique de la source de rayonnement, ont été caractérisés en utilisant les spectres de rotation du formaldéhyde et du monoxyde de carbone. L’analyse étendue de la structure de rotation de HDCO, D2CO et des espèces isotopiques 13C, 17O, 18O, et 13C18O est également présentée. Par ailleurs nous avons étudié le spectre de rotation millimétrique et térahertz de 3 molécules atmosphériques importantes : la méthacroléine et le méthyl vinyl cétone, les produits principaux d’oxydation de l’isoprène, et le nitrite d’éthyle, un produit de combustion des carburants à base de l’alcool et d’oxydation photochimique de composés organiques volatils. Ces molécules complexes sont caractérisées par des différents mouvements de grande amplitude. En particulier la torsion du groupement méthyle a été modélisée à la précision expérimentale pour l’état fondamental et les premiers états excités de vibration pour la méthacroléine et le méthyl vinyl cétone. Nous fournissons ainsi une information indispensable pour l’analyse détaillée des spectres infrarouges enregistrés par la spectroscopie infrarouge à haute résolution, dans les fenêtres atmosphériques. / We present the molecular spectroscopy results with the experimental developments and the analyses of high resolution spectra of molecules of atmospheric interest. We set up and tested a new frequency multiplication chain intended to extend the range of THz spectrometer in the PhLAM laboratory. The important parameters of the spectrometer, such as sensitivity, measurement precision and harmonic composition of the radiation source, were characterized using the rotational spectra of two simple molecules: formaldehyde and carbon monoxide. The extended analysis of rotational structure of HDCO, D2CO and 13C, 17O, 18O, and 13C18O isotopic species is also presented.Furthermore we studied the millimeterwave and terahertz rotational spectrum of 3 significant atmospheric molecules: methacrolein and methyl vinyl ketone, the main oxidation products of isoprene, and ethyl nitrite, a combustion product of alcohol based fuels and of photochemical oxidation of volatile organic compounds. These complex molecules are characterized by different large amplitude motions. In particular, the methyl group torsion was modeled in the experimental accuracy for the ground and the lowest excited vibrational states for methacrolein and methyl vinyl ketone. We thus provide an essential information for the detailed analysis of infrared spectra, recorded by high-resolution infrared spectroscopy, in the atmospheric windows.
15

Implementation of RSA Cryptosystem for Next Generation RFID Tags

Dighe, Ashish Arun January 2011 (has links)
This thesis addresses concepts of implementing a RSA cryptosystem on a passive RFID tag. With a limited number of public key cryptosystems on passive RFID platforms, the proposed algorithm makes use of Montgomery multiplication primitives to reduce the amount of computation required on the power constrained tag therefore making the proposition viable. Public key cryptography is being suggested for next generation RFID systems to reduce the number of possible attack vectors native to this type of technology. By estimating the area, power and time constraints of the RFID platform, it was determined that the area constraint was the critical variable in determining the maximum implementable security variable. Although the application of this algorithm has been targeted for passive HF RFID platforms, the algorithm could be used in other low power, sized constrained applications.
16

The effect of the intertrial interval on the acquisition and retention of novel multiplication facts

Jordan, Donald Bruce January 1969 (has links)
The study investigated the effect of the intertrial interval on the learning of novel multiplication facts by grade three students. For nine consecutive school days the experimenter played tape recorded treatments to the students. A treatment consisted of the oral presentation of a list of fifteen novel multiplication problems and corresponding answers read through twice in a random order. A 3-second response interval was allowed between the reading of a problem and the reading of the corresponding answer. The time interval between the reading of an answer and the reading of the next problem was defined as the intertrial interval. The sample of 210 grade three students was divided into three groups. One group had an intertrial interval of 3 seconds, the second group had an intertrial interval of 7 seconds, and the third group had an intertrial interval of 12 seconds. Fifteen novel problems were determined from an item analysis of a forty-problem pre-test administered before the treatments began. A post-test consisting of only the fifteen novel problems was administered immediately following the last treatment. A retention test consisting of a random order of the fifteen novel problems was administered ten days after the last treatment. Acquisition was defined as the difference between the post-test score and the pre-test novel score. Retention was defined as the difference between the retention test score and the pre-test novel score. A one-tailed t test was used to test the significance of the mean acquisition score within each group. A two-tailed t test was used to test the significance of the mean retention score within each group. The significance of the difference in the mean acquisition and retention scores between groups was tested using analysis of covariance and Tukey's procedure for comparing individual means. Acquisition and retention within each treatment group were significant beyond the .001 level. In both acquisition and retention the 7-second group and the 12-second group performed significantly better (p<.001) than the 3-second group. There was no significant difference between the 7-second group and the 12-second group in either acquisition or retention. For the task at hand, the results indicated that 7 seconds was a good approximation to the optimal intertrial interval. / Education, Faculty of / Graduate
17

Benchmarking for multiplicative model with monthly-annual data.

January 2010 (has links)
Ma, Chung Ho. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 56-57). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Additive model --- p.3 / Chapter 1.2 --- Multiplicative model --- p.4 / Chapter 2 --- Review of benchmarking methods --- p.7 / Chapter 2.1 --- Regression Method and Signal Extraction Method (Additive Case) --- p.7 / Chapter 2.1.1 --- Regression method for Additive model --- p.8 / Chapter 2.1.2 --- Signal extraction method with known auto-covariance of signal for Additive model --- p.9 / Chapter 2.1.3 --- Signal extraction method with unknown auto-covariance of signal for Additive model --- p.10 / Chapter 2.2 --- Regression Method and Signal Extraction Method (Multiplicative Case) --- p.15 / Chapter 2.2.1 --- Regression method for Multiplicative model --- p.15 / Chapter 2.2.2 --- Signal extraction method for Multiplicative model --- p.17 / Chapter 3 --- Benchmarking using an assigned error model --- p.21 / Chapter 3.1 --- Model setting --- p.22 / Chapter 3.2 --- Simulation procedures --- p.24 / Chapter 3.3 --- Simulation results --- p.26 / Chapter 3.3.1 --- Comparison of benchmarking methods for multiplicative model --- p.34 / Chapter 3.3.2 --- Suggestions on the selection of an assigned error model --- p.39 / Chapter 3.4 --- Summary on the effects of CV and Φ --- p.44 / Chapter 4 --- Error modelling by using benchmarks --- p.47 / Chapter 4.1 --- Benchmark Forecasting Method --- p.47 / Chapter 4.2 --- Benchmarking using an estimated error model --- p.49 / Chapter 4.3 --- Comparison of the best Φ and the estimated Φ on the benchmarking prediction --- p.53 / Chapter 5 --- Conclusion --- p.54 / Bibliography --- p.56
18

Fast Matrix Multiplication via Group Actions

Orem, Hendrik 01 May 2009 (has links)
Recent work has shown that fast matrix multiplication algorithms can be constructed by embedding the two input matrices into a group algebra, applying a generalized discrete Fourier transform, and performing the multiplication in the Fourier basis. Developing an embedding that yields a matrix multiplication algorithm with running time faster than naive matrix multiplication leads to interesting combinatorial problems in group theory. The crux of such an embedding, after a group G has been chosen, lies in finding a triple of subsets of G that satisfy a certain algebraic relation. I show how the process of finding such subsets can in some cases be greatly simplified by considering the action of the group G on an appropriate set X. In particular, I focus on groups acting on regularly branching trees.
19

Improving the Karatsuba-Ofman multiplication algorithm for special applications

Erdem, Serdar S. 08 November 2001 (has links)
In this thesis, we study the Karatsuba-Ofman Algorithm (KOA), which is a recursive multi-precision multiplication method, and improve it for certain special applications. This thesis is in two parts. In the first part, we derive an efficient algorithm from the KOA to multiply the operands having a precision of 2[superscript m] computer words for some integer m. This new algorithm is less complex and three times less recursive than the KOA. However, the order of the complexity is the same as the KOA. In the second part of the thesis, we introduce a novel method to perform fast multiplication in GF(2[superscript m]), using the KOA. This method is intended for software implementations and has two phases. In the first phase, we treat the field elements in GF(2[superscript m]) as polynomials over GF(2) and multiply them by a technique based on the KOA, which we call the LKOA (lean KOA). In the second phase, we reduce the product with an irreducible trinomial or pentanomial. The LKOA is similar to the KOA. However, it stops the recursions early and switches to some nonrecursive algorithms which can efficiently multiply small polynomials over GF(2). We derive these nonrecursive algorithms from the KOA, by removing its recursions. Additionally, we optimize them, exploiting the arithmetic of the polynomials over GF(2). As a result, we obtain a decrease in complexity, as well as a reduction in the recursion overhead. / Graduation date: 2002
20

Generating just temperament with ideal rate multiplication /

Moore, Andrew C. January 1991 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1991. / Typescript. Includes bibliographical references (leaves 59-60).

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