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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.
111

Propriétés algébriques et analytiques de certaines suites indexées par les nombres premiers / Algebraic and analytic properties of some sequences over prime numbers

Devin, Lucile 26 June 2017 (has links)
Dans la première partie de cette thèse, on s'intéresse à la suite NX(p) [mod p] où X est un schéma séparé réduit de type fini sur Z,et pour tout p premier, NX(p) est le nombre de Fp-points de la réduction modulo p de X.Sous certaines hypothèses sur la géométrie de X, on donne une condition simple pour garantir que cette suite diffèreen une densité positive de coordonnées de la suite identiquement nulle,ou plus généralement de suites dont les coordonnées sont obtenues par réduction modulo p d'un nombre fini d'entiers.Dans le cas où X parcourt une famille de courbes hyperelliptiques, on donne une borne en moyenne sur le plus petit premier p pour lequel NX (p) [mod p] n'est pas dans un certain ensemble de valeurs fixées.La seconde partie est dédiée à des généralisations de la notion de biais de Chebyshev.On se donne une fonction L vérifiant certaines propriétés analytiquesgénéralisant celles vérifiées par les fonctions L de Dirichlet.On s'intéresse à la suite des coefficients de Fourier a_p pour p premier.Plus précisément on étudie le signe de la fonction sommatoire des coefficients de Fourier de la fonction L.On montre sous des conditions classiques que cette fonction admet une distribution logarithmique limite.Sous des hypothèses supplémentaires on obtient de bonnes propriétés telles que la régularité, la symétrie et des informations sur le support de cette distribution. / In the first part of this Thesis, we study the sequence NX (p) [mod p] where X is a reduced separated scheme of finite type over Z,and NX (p) is the number of Fp-points of the reduction modulo p of X, for every prime p. Under some hypotheses on the geometry of X, we give a simple condition to ensure that this sequence is distinctat a positive proportion of indices from the zero sequence,or generalizations obtained by reduction modulo p of finitely many integers.We give a bound on average over a family of hyperelliptic curves for the least prime p such that NX (p) [mod p] avoids the reductionmodulo p of finitely many fixed integers.The second part deals with generalizations of Chebyshev’s bias.We consider an L-function satisfying some analytic properties that generalize those satisfied by Dirichlet L-functions.We study the sequence of coefficients a_p as p runs through the set of prime numbers.Precisely, we study the sign of the summatory function of the Fourier coefficients of the L-function.Under some classical conditions, we show that this function admits a limiting logarithmic distribution.Under stronger hypotheses, we prove regularity, symmetry and get information about the support of this distribution.
112

Techniky paralelního zpracování výpočtů / Techniques for parallel computing

Vodák, René January 2014 (has links)
The text of this thesis deals with techniques of parallel processing calculations. It is an analysis of the most important libraries for parallelization including libraries for parallelization on GPU graphics cards and computing speed by comparing these libraries in Visual Studio 2010 based on a simple application searching primes on three different computer hardware configurations. With OpenCL library, that achieved the best result, there are formed two applications – an improved program for searching prime numbers using the sieve of Eratosthenes and a program for calculating the integral with the trapezoidal rule.
113

Návrh konstrukce omílácího stroje / Suggestion of tumbling machine's construction

Matula, Petr January 2014 (has links)
The master´s thesis deals with a suggestion of vibratory tumbling machine´s construction for tumbling of brass cartridges. The thesis contains theoretical part which describes the principle of tumbling and its possibility of using, further characterizes various types of tumbling machines and their parts. Practical part of thesis includes functional calculations of vibratory tumbling machines, draft of power, compression springs bearing tumbling container and control calculation of these springs. Complete tumbling machine is created in a 3D modeling program. Drawing documentation which includes individual drawings of assemblies, secondary assemblies and their particular parts according to task is enclosed.
114

Relation between Feed Particle Size Distribution and Plumage Condition in Laying Hens on Commercial Farms

Schreiter, Ruben, Damme, Klaus, Freick, Markus 24 February 2022 (has links)
Feather pecking is a serious problem in laying hen husbandry, which can lead to feather damage, performance losses and economic disadvantages. In this context, feed has been identified as an important factor, whereby scientific knowledge is primarily available on the effect of ingredients but hardly on the feed structure. In this study, feed samples from feather pecking and non-feather pecking herds from production farms were analyzed for their nutrient contents and feed particle sizes. More coarser (>2.00 mm) and fewer medium and finer feed particles (≤1.60 mm) were found in the feed of the flocks affected by feather pecking. The coarser components contained lower levels of nutrients important for preventing feather pecking (e.g., methionine, sodium). The study demonstrated that a feed structure that is too coarse can be considered a risk factor for feather pecking. / Die Studie untersucht die Zusammensetzung der Futterpartikelfraktionen und deren Nährstoffgehalte in Legehennenfutter. Hierfür wurden 103 Futterproben von federpickenden (AH, n=37) und nicht-federpickenden Herden (CH, n=66) von Produktionsbetrieben mittels trockener Siebanalyse und Nährstoffanalytik untersucht. In den AH zeigten sich in der Futterstruktur im Vergleich zu den CH höhere Anteile an Partikeln >2,50 mm (MW ± STW: CH: 11,0 ± 8,5 %, AH: 24,9 ± 14,3 %) und 2,00-2,50 mm (CH: 11,2 ± 5,3 %, AH: 15,7 ± 5,7 %) bei niedrigeren Anteilen der Fraktionen 1,01-1,60 mm (CH: 22,9 ± 4,9 %, AH: 17,8 ± 5,7 %), 0,51-1,00 mm (CH: 25,5 ± 8,2 %, AH: 16,0 ± 6,8 %) und ≤0,50 mm (CH: 15,4 ± 5,0 %, AH: 11,0 ± 4,8 %) (p<0,001). Die Futter der AH (1470,8 ± 343,9 μm) wiesen dabei auch einen höheren geometrischen Durchmesser aus (GMD) im Vergleich zu den CH (1113,3 ± 225,7 μm) auf (p<0,001). Die vorgefundenen Anteile der Partikelgrößenfraktionen 1,01-1,60 mm und ≥2,50 mm lagen außerhalb des empfohlenen Referenzbereichs (p<0,001). Die Gehalte an Rohasche (CH: 130,3 ± 18,8 g/kg, AH: 115,9 ± 24,3 g/kg), Lysin (CH: 8,2 ± 1,0 g/kg, AH: 7,7 ± 1,2 g/kg), Methionin (CH: 3,4 ± 0,5 g/kg, AH: 3,2 ± 0,6 g/kg) und Natrium (CH: 1,7 ± 0,4 g/kg, AH: 1,3 ± 0,4 g/kg) waren bei den AH niedriger als in den CH (p≤0,041). Im Modell der logistischen Regression zeigten sich das Tieralter (p=0,041) und der GMD (p<0,001) als signifikante Einflussfaktoren auf das Auftreten von Federpicken. Anhand der Studie konnte gezeigt werden, dass eine zu grobe Futterstruktur als Risikofaktor für Federpicken zu betrachten ist.
115

Improvement of a Vermicompost Sieving Machine for Smallholder Farmers in the Philippines : A study conducted in science city of Muñoz, Philippines / Förbättring av en siktmaskin med maskkompostering för småskaliga bönder på Filippinerna

Marcos Yousif, Anokina, Vidal, Felipe, Cosaceanu, Ioana January 2023 (has links)
The Philippines has a primarily agricultural economy, with many rural residents relying on farming for their livelihoods. The Philippine Carabao Center (PCC) was established in 1992 to support smallholder farmers in the country through research and technology development related to carabaos. The PCC's national headquarters in Nueva Ecija's Science City of Muñoz maintains a herd of approximately 400 carabaos and uses a drum sieve to separate the vermicompost from the carabaos for sale and efficient manure management. Vermicomposting is a profitable form of agriculture in the country, utilizing African night crawler worms to convert biodegradable waste materials into organic fertilizer. However, many smallholder farmers who wish to start vermicomposting do not have access to a sieve machine as they are often too expensive. Neighboring farmers often form cooperatives with at least 15 members who work together towards common goals. Because these cooperatives offer services such as loans, training, and equipment access, they would be able to provide a sieve machine for their members and therefore the individual farmer would have a greater chance to be able to start vermicomposting. This study was aimed at designing a more accessible sieve machine for low-income smallholder farmers. The resulting design is a manually-driven machine operated through a pedal mechanism. The machine is smaller, easier to maintain and has no drift costs in comparison to the existing machine at PCC. It has integrated wheels and brakes, a brush for clearing clogged holes, and a collector. However, no physical prototype was made to verify its implementation. The concept is made of a mix of raw materials and purchased components, with the raw materials sourced from the Philippines and the components possibly imported. The estimated price was around PHP 58,468, which was less than the PCC machine, considered reasonable for cooperatives but may not be affordable for individual smallholder farmers. / Filippinerna huvudsakligen en jordbruksbaserad ekonomi, många invånare på landsbygden förlitar sig på jordbruk som sin huvudsakliga inkomstkälla. Philippine Carabao Center (PCC) grundades 1992 för att stödja småskaliga jordbrukare genom forskning och teknikutveckling relaterat till carabao. PCC:s nationella huvudkontor i Science City of Muñoz i Nueva Ecija har en flock på cirka 400 carabaos och använder en trumsikt för att separera maskkompost av carabaos för försäljning och effektiv gödselhantering. Maskkompostering är en lönsam form av jordbruk i landet, där afrikansk nattkrälande maskar används för att omvandla nedbrytbara avfallsmaterial till organisk gödsel. Småbrukare som önskar börja med maskkompostering saknar dock tillgång till en siktmaskin då de ofta är för dyra. Grannbrukare bildar dock ofta kooperativ med minst 15 medlemmar som arbetar tillsammans mot gemensamma mål. Eftersom dessa kooperativ erbjuder tjänster såsom lån, utbildning och tillgång till utrustning skulle de kunna tillhandahålla en siktmaskin för sina medlemmar och därmed öka chansen för den enskilda småbrukaren att kunna börja med maskkompostering. Syfte med det här arbetet var att utforma en mer tillgänglig siktmaskin för låginkomsttagande småskaliga jordbrukare. Den resulterande designen är en manuellt driven maskin som drivs med en pedalmekanism. Maskinen är utformad för att vara mindre, enklare att underhålla och har inga driftkostnader jämfört med den befintliga maskinen på PCC. Den har integrerade hjul och bromsar, en borste för att rensa igensatta hål och en samlare. Framtida arbetet är att ta fram en fysisk prototyp för att kunna verifiera konceptet. Maskinen består av en blandning av råvaror och inköpta komponenter, där råvarorna kom från Filippinerna och komponenterna möjligen var importerade. Maskinens uppskattade pris blev cirka 58 468 PHP, mindre än ursprungliga PCC-maskinen, och anses rimligt för kooperativet, men kanske inte överkomligt för enskilda småskaliga jordbrukare.
116

On Two Computational Models of the Pitch-Rhythm Correspondence: A Focus on Milton Babbit’s and Iannis Xenakis’s Theoretical Constructions

Andreatta, Moreno 23 October 2023 (has links)
No description available.
117

Asymptotic Analysis for Nonlinear Spatial and Network Econometric Models

Xu, Xingbai, Xu 28 September 2016 (has links)
No description available.
118

Evaluación de la calidad del concreto hidráulico usando agregado fino marginal en el proyecto rehabilitación y mejoramiento de la carretera DV. Imperial – Pampas

Paredes Carrasco, Alexander Edward, Guillen Herrera, Edson Rodolfo January 2015 (has links)
Para la presente investigación de tesis desarrollada entre los distritos de Imperial y Pampas, provincia de Tayacaja, en el departamento de Huancavelica, se tiene como unidad de análisis a 60 muros de contención, donde se aplicó criterios muestréales de 23 muros f´c 210 kg/cm2. Como resultados alcanzados se logró elaborar concreto hidráulico de calidad usando agregado fino marginal con el cual se pudo satisfacer los parámetros de resistencia y durabilidad. Para demostrar la durabilidad se realizaron distintos ensayos; los que no cumplieron con las especificaciones de la norma EG-2000 fueron el de Equivalente de arena MTC E 114, Material que pasa el Tamiz N°200 MTC E 202 y Análisis granulométrico por tamizado ASTM C 136, por lo cual se efectuaron análisis más rigurosos como: el ensayo de Valor de azul de metileno y el ensayo de Análisis petrográfico macroscópico y microscópico en agregados para concreto ASTM C 295, donde se obtuvo como resultado que la arena no presenta elementos activos en su composición, lo que quiere decir que ante las condiciones ambientales de la zona estos elementos no se expanden ni se contraen y adicionalmente como medida de control se diseñó la mezcla de concreto hidráulico con aditivo incorporador de aire AirMix-200. Del mismo informe petrográfico se concluyó que la composición principal del agregado es la caliza, la cual es materia prima para la elaboración del cemento, que de alguna manera adicional ayuda a cumplir satisfactoriamente el parámetro de resistencia. Así mismo quedó demostrado que a través de ensayos a compresión no confinada de testigos de concreto, se alcanzó resistencias superiores a lo requerido en la norma EG-2000. Research for this thesis developed between the districts of Imperial and Pampas, Tayacaja province, in the department of Huancavelica, it has the analysis unit 60 retaining walls, where 23 sample criteria applied walls f´c 210 kg/cm2. Results obtained are as elaborate hydraulic concrete achievement of marginal quality using fine aggregate with which it was able to satisfy the parameters of strength and durability. To demonstrate the durability various tests were performed; those who do not comply with the specifications of the EG-2000 were rule the sand equivalent MTC E 114, passes what material the sieve No. 200 MTC E 202 and sieve analysis ASTM C 136, here by which they were made Analysis More rigorous like: The test value of methylene blue and testing of macroscopic and microscopic petrographic analysis in paragraph aggregate concrete ASTM C 295, where it resulted the sand without presents elements active in their composition, which means they say to the area Environmental Conditions These elements do not expand or contract and additionally as a control measure of self-design hydraulic concrete mix with entraining admixture AirMix-200 air. Same petrographic report concluded that the composition of the director of aggregate is limestone, which is a raw material for the production of cement, which in some additionally helps one perform satisfactorily resistance parameter. Also it demonstrated that one through essays of unconfined compressive concrete witness, higher strengths than required was reached in the EG-2000 standard.
119

Integer Factorization on the GPU / Integer Factorization on the GPU

Podhorský, Jiří January 2014 (has links)
This work deals with factorization, a decomposition of composite numbers on prime numbers and possibilities of its parallelization. It summarizes also the best known algorithms for factoring and most popular platforms for the implementation of these algorithms on the graphics card. The main part of the thesis deals with the design and implementation of hardware acceleration current fastest algorithm on the graphics card by using the OpenCL framework. Subsequently, the work provides a comparison of speeds accelerated algorithm implemented in this work with other versions of the best known algorithms for factoring, processed serially. In conclusion, the work discussed length of RSA key needed for safe operation without the possibility of breaking in real time interval.
120

Entiers friables et formes binaires / Friable integers and binary forms

Lachand, Armand 02 December 2014 (has links)
Un entier est dit y-friable si tous ses facteurs premiers n'excèdent pas y. Les valeurs friables de formes binaires interviennent de manière essentielle dans l'algorithme de factorisation du crible algébrique (NFS). Dans cette thèse, nous obtenons des formules asymptotiques pour le nombre de représentations des entiers friables par différentes familles de polynômes. Nous considérons dans la première partie les formes binaires qui se décomposent comme produit d'une forme linéaire et d'une forme quadratique. Nous combinons pour cela le principe d'inclusion-exclusion à des idées issues de travaux sur la distribution multiplicative de certaines suites d'entiers représentés par des formes quadratiques développés par Fouvry et Iwaniec, puis Balog, Blomer, Dartyge et Tenenbaum. Dans un second temps, nous nous concentrons sur les valeurs friables de formes cubiques irréductibles. En adaptant les travaux de Heath-Brown et Moroz sur les nombres premiers représentés par de tels polynômes, nous obtenons des formules asymptotiques valides dans un vaste domaine de friabilité. Notre méthode permet également d'évaluer des moyennes sur les valeurs d'une forme cubique pour d'autres fonctions arithmétiques comprenant en particulier les fonctions de Möbius et de Liouville. Dans le dernier chapitre, nous étudions les corrélations de l'indicatrice des friables avec les nilsuites. En employant la méthode nilpotente de Green et Tao, nous en déduisons une formule pour le nombre de valeurs friables d'un produit de formes affines deux à deux affinement indépendantes / An integer is called y-friable if its largest prime factor does not exceed y. Friable values of binary forms play a central role in the integer factoring algorithm NFS (Number Field Sieve). In this thesis, we obtain some asymptotic formulas for the number of representations of friable integers by various classes of polynomials. In the first part, we focus on binary forms which split as a product of a linear form and a quadratic form. To achieve this, we combine the inclusion-exclusion principle with ideas based on works of Fouvry and Iwaniec and Balog, Blomer, Dartyge and Tenenbaum related to the distribution of some sequences of integers represented by quadratic forms. We then take a closer look at friable values of irreducible cubic forms. Extending some previous works of Heath-Brown and Moroz concerning primes represented by such polynomials, we provide some asymptotic formulas which hold in a large range of friability. With this method, we also evaluate some means over the values of an irreducible cubic form for other multiplicative functions including the Möbius function and the Liouville function. In the last chapter, we investigate the correlations between nilsequences and the characteristic function of friable integers. By using the nilpotent method of Green and Tao, our work provides a formula for the number of friable integers represented by a product of affine forms such that any two forms are affinely independent

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