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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.
91

Certain problems concerning polynomials and transcendental entire functions of exponential type

Hachani, Mohamed Amine 06 1900 (has links)
Soit P(z):=\sum_{\nu=0}^na_\nu z^{\nu}$ un polynôme de degré n et M:=\sup_{|z|=1}|P(z)|.$ Sans aucne restriction suplémentaire, on sait que $|P'(z)|\leq Mn$ pour $|z|\leq 1$ (inégalité de Bernstein). Si nous supposons maintenant que les zéros du polynôme $P$ sont à l'extérieur du cercle $|z|=k,$ quelle amélioration peut-on apporter à l'inégalité de Bernstein? Il est déjà connu [{\bf \ref{Mal1}}] que dans le cas où $k\geq 1$ on a $$(*) \qquad |P'(z)|\leq \frac{n}{1+k}M \qquad (|z|\leq 1),$$ qu'en est-il pour le cas où $k < 1$? Quelle est l'inégalité analogue à $(*)$ pour une fonction entière de type exponentiel $\tau ?$ D'autre part, si on suppose que $P$ a tous ses zéros dans $|z|\geq k \, \, (k\geq 1),$ quelle est l'estimation de $|P'(z)|$ sur le cercle unité, en terme des quatre premiers termes de son développement en série entière autour de l'origine. Cette thèse constitue une contribution à la théorie analytique des polynômes à la lumière de ces questions. / Let P(z):=\sum_{\nu=0}^na_\nu z^{\nu}$ a polynomial of degree n and M:=\sup_{|z|=1}|P(z)|$. Without any additional restriction, we know that $|P '(z) | \leq Mn$ for $| z | \leq 1$ (Bernstein's inequality). Now if we assume that the zeros of the polynomial $P$ are outside the circle $| z | = k$, which improvement could be made to the Bernstein inequality? It is already known [{\bf \ref{Mal1}}] that in the case where $k \geq 1$, one has$$ (*) \qquad | P '(z) | \leq \frac{n}{1 + k} M \qquad (| z | \leq 1),$$ what would it be in the case where $k < 1$? What is the analogous inequality for an entire function of exponential type $\tau$? On the other hand, if we assume that $P$ has all its zeros in $| z | \geq k \, \, (k \geq 1),$ which is the estimate of $| P '(z) |$ on the unit circle, in terms of the first four terms of its Maclaurin series expansion. This thesis comprises a contribution to the analytic theory of polynomials in the light of these problems.
92

Etude de la fertilité et du métabolisme des vaches laitières sélectionnées pour l'haplotype "fertil+" ou "fertil-" à un QTL de fertilité situé sur le chromosome 3 / Fertility and metabolism of dairy cows carrying "Fertil+" or "Fertil-" haplotype for a fertility QTL located on the chromosome 3

Coyral-Castel, Stéphanie 06 July 2012 (has links)
Au cours des dernières décennies, une dégradation de la fertilité des vaches laitières, parallèlement à une augmentation de la production laitière a été observée. Des régions du génome, les QTL, affectent la fertilité femelle. Le but de ce travail de thèse est d’étudier la fertilité et certains paramètres zootechniques chez des vaches Prim'Hosltein en première lactation choisies pour leur haplotype favorable "fertil+" ou défavorable "fertil-" pour un QTL de fertilité situé sur le chromosome 3. Ce phénotypage a montré une meilleure fertilité et un meilleur bilan énergétique dans la première semaine de lactation pour les vaches "fertil+" par rapport aux vaches "fertil-". De plus, les vaches "fertil-" ont un flux d’ingestion plus rapide. Au pic de mobilisation, certains gènes du QTL étaient différentiellement exprimés dans le tissu adipeux des deux haplotypes. Dans les cellules de la granulosa, un de ces gènes, nommé Kirrel, est plus exprimé chez les vaches "fertil+" et sa protéine recombinante inhibe la sécrétion de progestérone in vitro. Notre travail a permis d'affiner les interactions génotype-phénotype liées à un QTL de fertilité et de mettre en avant un des possibles rôles d'un gène de ce QTL dans la fonction de reproduction chez la vache laitière. / In recent decades, the dairy cow fertility has declined, in parallel with an increase in milk production. Some regions of the genome, named QTL, affect female fertility. The purpose of this thesis is to study fertility and some zootechnical parameters in Prim'Hosltein cows in first lactation chosen for their favorable haplotype "fertil+" or unfavorable haplotype "fertil-" for one fertility QTL on chromosome 3. This phenotyping showed better fertility and energy balance in the first week of lactation for "fertil+" than for "fertil-" cows. In addition, "fertil-" cows had a higher eating rate. At the peak of mobilization, the QTL genes are differentially expressed in adipose tissue of "fertil+" and "fertil-" cows. In granulosa cells, one of these genes, named Kirrel, is higher expressed in "fertil+" cows and its recombinant protein inhibits the secretion of progesterone in vitro. Our work has contributed to refine interactions genotype-phenotype linked to one fertility QTL and highlighted one of the possible roles of a gene which belongs to this QTL in the reproductive function in dairy cows.
93

Synthesis of small molecules targeting filovirus inhibition / Synthèse de petites molécules ciblant l'inhibition filovirus

Niemiec-Plebanek, Elzbieta 19 December 2014 (has links)
Les virus sont au centre de problème de santé publique. En raison de l'apparition de nouveaux virus et pour certains de leur résistance aux traitements existants il est toujours d’actualité de développement de nouveaux agents antiviraux. En général, la stratégie de lutte contre les infections virales est basée sur la vaccination ou sur l'activité des petites molécules, interférant avec un ou plusieurs processus biologiques participant au cycle de vie du virus. Dans ce contexte, nous avons conçu et synthétisé des petites bibliothèques de molécules visant des propriétés anti-filovirus. Dans ce projet de recherche, nous avons mis l'accent sur le développement de composés ciblant la protéine Niemann-Pick C1, les protéases cathepsine et le processus de réplication. Lors du développement des inhibiteurs de Neimann-Pick C1 plus de 70 composés ont été synthétisés, portant le squelette pipérazine. Afin d'obtenir des inhibiteurs de cystéine cathepsines pouvant être impliqués dans la réplication du virus Ebola, nous avons synthétisé une petite bibliothèque de composés porteurs de groupement 1,3,5-triazine et possédant des activité de l’ordre du nanomolaire sur les cathepsines B, K, L et S. Enfin, pour inhiber la réplication du virus en ciblant SAH hydrolase, nous avons proposé une série de C-nucléosides carbocyclic ayant motif de 4-aza-7,9-dideazaadenosine. / The viruses cause the problem of public health. Due to the appearance of new viruses and their resistance to existing treatments there is still relevant to develop new antivirals. Generally, the strategy to combat viral infections is based on vaccination or on the activity of small molecules, interfering with one or more biological processes participating in virus life cycle. In this context, we took an effort to design and synthesize the library of small molecules possessing anti-filovirus properties. In this research project, we were focused on the developing of compounds targeting Niemann-Pick C1 protein, cathepsin proteases and replication process. In our effort into the development of the inhibitors of Neimann-Pick C1 we prepared the series of about 70 compounds, having in common the piperazine moiety. Diverse 1,4-N,N - substituents of piperazine, differencing in a size and shape were studied. In order to obtain efficient cysteine cathepsins inhibitors, we synthesized the small library of compounds bearing 1,3,5-triazine moiety. Finally, to inhibit the virus replication by targeting SAH hydrolase, we proposed the series of carbocyclic C-nucleosides having motif of 4-aza-7,9-dideazaadenosine.
94

Medidas e forma em geometria / Measures and shaped geometry

Edjan Fernandes dos Santos 31 August 2015 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / O trabalho traz inicialmente uma abordagem histÃrica, da GrÃcia (com os pitagÃricos), com o matemÃtico Eudoxo, fazendo referÃncia a talvez à maior obra matemÃtica, os livros de Euclides. Em seguida, trazemos definiÃÃes e construÃÃes sobre os nÃmeros reais com um corpo completo, os conceitos de Ãnfimo, supremo, sequÃncias infinitas com destaque as convergentes, sequÃncia de Cauchy e os trÃs teoremas fundamentais para o curso de cÃlculo, o teorema do anulamento, do valor intermediÃrio e de Weierstrass. Logo apÃs, definimos mÃtrica e espaÃo mÃtrico no plano, mostramos que o processo de comparar um segmento arbitrÃrio com outro fixado como unidade nos conduz aos diversos tipos de nÃmeros reais positivos: inteiros, racionais e irracionais, onde a noÃÃo de segmento comensurÃvel à explicada. O cÃlculo de Ãrea para figuras planas, onde sÃo apresentadas as fÃrmulas usuais para as Ãreas dos polÃgonos mais simples, apresentamos uma aplicaÃÃo, a fÃrmula de Pick, sem demonstraÃÃo do teorema, simples, divertida, prÃtica e eficiente para o cÃlculo de Ãrea, um conteÃdo da disciplina de matemÃtica presente em todo o ensino bÃsico do Brasil sempre presente em avaliaÃÃes externas como a OBMEP. / The work initially brings a historical approach, Greece (with the Pythagoreans), with the mathematician Eudoxus, referring to perhaps the greatest mathematical work, Euclidâs books. Then bring definitions and constructions of the real numbers as a complete body, the concepts of tiny, supreme, infinite sequences especially the convergent, Cauchy sequences and the three fundamental theorems for the calculus course, the annulment of the theorem, the intermediate value and Weierstrass. Soon after, we define metric and metric space in the plan, we show that the process of comparing an arbitrary segment with another set as unit leads to various types of positive real numbers: integers, rational and irrational, where the notion of measurable and immeasurable segment is explained. The area calculation for plane figures, where the usual formulas for the areas of simple polygons are presented, we present and application, Pickâs formula, without demonstration of the theorem, simple, fun, practical and efficient for area calculation, one this mathematical discipline of content throughout basic education in Brazil always present in external evaluation as OBMEP.
95

Návrh robotické buňky pro svařování a manipulaci / Design of a Robotic Cell for Welding and Manipulation

Lukačovič, Peter January 2018 (has links)
The purpose of this master’s thesis is a design of the robotic cell for spot welding followed by manipulation with parts assigned for automotive industry. The cell should consist of a rotary table operated by a process operator and set of six-axis robots for spot welding and manipulation with parts. The thesis also describes the design of the end effectors of all robots, the design of rotary table with regard to welding technology and configuration of the cell to obtain maximal efficiency. The output of the thesis is 3D model, workflow simulation, evaluation of the production times and operator work conditions.
96

Návrh robotické buňky pro obsluhu vstřikolisů / Design of a Robotic Cell for Injection Molding Machines Operations

Franc, Vladimír January 2019 (has links)
The aim of this thesis is to design a robotic cell for automated injection molding operation. At the beginning of this paper, the input parameters and the assignment are analyzed. This is then followed up by the layout of the workplace, design of its equipment, selection of robots and the design of their end effectors and peripherals with regard to the specified boundary conditions and operator’s safety. The output of this work is a 3D cell model and its simulation model in PLM software Siemens Process Simulate, which verifies the production cycle time.
97

Från periodisk inventering utan Pick By Voice till rullande inventering med Pick By Voice : En fallstudie på Företag X / From periodic inventory without Pick By Voice to continuous inventory with Pick By Voice : A case study at Company X

Vinberg, Karl, Holm, Jacob, Basic, Amer January 2020 (has links)
Titel: Från periodisk inventering utan Pick By Voice till rullande inventering med Pick By Voice - En fallstudie på Företag X Bakgrund och problem: Företag X har valt att implementera plocktekniken Pick By Voice, samtidigt som företaget ser över möjligheten att implementera en rullande inventering i samband med detta. Frågor som uppstår är vad lagar och praxis säger för området samt hur en möjlig implementering av rullande inventering bör se ut. Syfte: Syftet med uppsatsen är att genom en kvalitativ studie undersöka behovet av en ny inventeringsmetod genom en förstudie och därefter utveckla en inventeringsprocess passande efter Företag X förutsättningar. Denna inventeringsprocess ska kunna användas i samspel med Pick By Voice. Vidare är också att uppmuntra andra företag inom likartad bransch att se över sin nuvarande inventeringsmetod och om de kan implementera en liknande förändring av rullande inventering med Pick By Voice. Metod: Denna studie är en kvalitativ fallstudie. Insamlingen av empiri har skett genom utförandet av semistrukturerade och ostrukturerade intervjuer med företag och revisionsbyråer. Slutsats: En nu 65 år gammal skattelag säger att företag måste inventera sina lager minst en gång om året. Som en otillräcklig beskrivning av hur detta ska göras, samtidigt som lagerhanteringssystemet får ny utveckling, har detta lagt större vikt vid nuvarande praxis. Detta är särskilt så när ett företag implementerar en rullande inventeringsmetod. Viktiga steg i implementeringsprocessen bekräftas vara avgörande för företag att uppfylla. Dels för att lyckas med implementeringen, men också för att säkerställa en tillfredsställande inventeringsprocess och undvika att både misstag i implementerings- och inventeringssprocessen uppstår. Att kombinera den rullande inventeringen med röstplocktekniken Pick By Voice anses även det vara betydande för att reducera ytterligare misstag som förekommer eller kan förekomma i inventeringsprocessen. Hur frekvent företag bör inventera grundar sig i; vilken typ av marknad företaget är verksamt på, andelen misstag som uppstår i inventeringsprocessen och om fler antal inventeringar kan bidra till fler besparingar för företaget. / Title: From periodic inventory without Pick By Voice to continuous inventory with Pick By Voice - A case study at Company X Background and problem: Company X has chosen to implement the Pick By Voice picking technology, while at the same time considering the possibility of implementing a continuous inventory in connection with this. Questions that arise are what the laws and practices say for this area and what a possible implementation of continuous inventory should look like. Purpose: The purpose of this thesis is to investigate the need for a new inventory method through a pilot study and then develop an inventory process suitable for Company X conditions. This inventory process should be used in interaction with Pick By Voice. Furthermore, other companies in similar industries are also encouraged to review their current inventory method and whether they can implement a similar change of continuous inventory with Pick By Voice. Method: This study is a qualitative case study. The collection of empirical data has been carried out through the conduct of semi structured and unstructured interviews with companies and accounting firms. Conclusion: A now 65 years old tax law says that companies need to count their inventory at least once a year. As there is an insufficient description of how this should be done, while also warehouse management system get new development, this has placed greater emphasis on current practice. This so, especially when a company is implementing a continuous inventory method with Pick By Voice. Important steps in the implementation process have been confirmed to be crucial to fulfil by the company. Especially in order to achieve a successful implementation of the process, ensure that the process fulfil its required satisfaction level and to avoid occurrence of mistakes in the implementation process as well as in the inventory process. The combination of continuous inventory and Pick By Voice is considered to be significant in the reduction of further mistakes that occur or can occur in the inventory process. The determination of the inventory frequency is dependent on; type of market that the company operates in, number of occurring mistakes in the inventory process and if an increase in number of inventory occasions can contribute to an increase in the savings.
98

Méthodologies et outils de synthèse pour des fonctions de filtrage chargées par des impédances complexes / Methodologies and synthesis tools for functions filters loaded by complex impedances

Martinez Martinez, David 20 June 2019 (has links)
Le problème de l'adaptation d'impédance en ingénierie des hyper fréquences et en électronique en général consiste à minimiser la réflexion de la puissance qui doit être transmise, par un générateur, à une charge donnée dans une bande de fréquence. Les exigences d'adaptation et de filtrage dans les systèmes de communication classiques sont généralement satisfaites en utilisant un circuit d'adaptation suivi d'un filtre. Nous proposons ici de concevoir des filtres d'adaptation qui intègrent à la fois les exigences d'adaptation et de filtrage dans un seul appareil et augmentent ainsi l'efficacité globale et la compacité du système. Dans ce travail, le problème d'adaptation est formulé en introduisant un problème d'optimisation convexe dans le cadre établi par la théorie de d'adaptation de Fano et Youla. De ce contexte, au moyen de techniques modernes de programmation semi-définies non linéaires, un problème convexe, et donc avec une optimalité garantie, est obtenu. Enfin, pour démontrer les avantages fournis par la théorie développée au-delà de la synthèse de filtres avec des charges complexes variables en fréquence, nous examinons deux applications pratiques récurrentes dans la conception de ce type de dispositifs. Ces applications correspondent, d'une part, à l'adaptation d'un réseau d'antennes dans le but de maximiser l'efficacité du rayonnement, et, d'autre part, à la synthèse de multiplexeurs où chacun des filtres de canal est adapté au reste du dispositif, notamment les filtres correspondant aux autres canaux. / The problem of impedance matching in electronics and particularly in RF engineering consists on minimising the reflection of the power that is to be transmitted, by a generator, to a given load within a frequency band. The matching and filtering requirements in classical communication systems are usually satisfied by using a matching circuit followed by a filter. We propose here to design matching filters that integrate both, matching and filtering requirements, in a single device and thereby increase the overall efficiency and compactness of the system. In this work, the matching problem is formulated by introducing convex optimisation on the framework established by the matching theory of Fano and Youla. As a result, by means of modern non-linear semi-definite programming techniques, a convex problem, and therefore with guaranteed optimality, is achieved. Finally, to demonstrate the advantages provided by the developed theory beyond the synthesis of filters with frequency varying loads, we consider two practical applications which are recurrent in the design of communication devices. These applications are, on the one hand, the matching of an array of antennas with the objective of maximizing the radiation efficiency, and on the other hand the synthesis of multiplexers where each of the channel filters is matched to the rest of the device, including the filters corresponding to the other channels.
99

Investigation of MEMS-Based Acoustic Levitation for Pick-and-Place Machines / Utredning av MEMS-Baserad Akustisk Levitation för Pick-and-Place maskiner

Bergstrand, Alejandro, Malm, Lukas January 2021 (has links)
The standard technology used in a pick and place machine for lifting and transportingsurface mount electronic components is a vacuum based solution.  This thesis investigates a new acoustic based technology for manipulating surface mountelectronic components.  Using a microelectromechanical systems-based transducers array to create a standing wave, small objects and components were levitated and studied.  It was examined how the distance would affect the levitation ability of different objects with varying density as well as how the stability was affected. It was concluded that the distance variation of approximately 10 mm had no significant affecton the levitation ability. The longer distance did result in a less stable behavior of the levitated object. / Standardtekniken som används i en pick-and-placemaskin för att lyfta och förflytta ytmonterade elektroniska komponenter är baserad på en vakuumbaserad lösning. Detta examensarbete undersöker en ny akustisk baserad teknik för att manipulera ytmonterade elektroniska komponenter.  Med hjälp av en mikroelektromekaniskt system-baserad piezoelektrisk givare skapades en stående våg, för att levitera och studera små föremål och komponenter. Det undersöktes hur avståndet skulle påverka levitationsförmågan hos olika föremål med varierande densitet samt hur stabiliteten påverkades.  Slutsatsen som drogs var att avståndsvariationen på cirka 10 mm inte hade någon signifikant påverkan på levitationsförmågan. Det längre avståndet resulterade dock i ett mindre stabilt beteende hos det svävande föremålet.
100

A case study in the strategic analysis of Pick 'n Pay Stores Limited : 1967-1999

Heckroodt, Anneke 12 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: The South African business arena forms a rich platform for tertiary research in strategic management to post graduate students attending South African business schools. The problem exists, however, that very few of these case studies are written up and therefore available as research material to the students. The researcher contributes with this case study to the lean body of research material available for research of South African businesses. The chosen company for research purposes are Pick 'n Pay Stores Limited. This company is typically a leader in the food retailing industry. Information regarding this company is readily available, which increases the learning experience for the student. The study project is presented in the form of a case study that urges the student to work through the material and answer the questions. The questions are formulated with the purpose of guiding the student through the logical steps of a strategic analysis of a company. The case study also includes a model answer that serves the purpose of guiding the lecturer towards the expected answers to the questions of the case study. Initially the student is introduced to a model that could typically be used in the strategic analysis of a company. This model serves as a framework for the strategic analysis of Pick 'n Pay. The student is invited to use this model in the strategic analysis of the company. In so far as this model is not adequate, the student may introduce a new model as long as business-minded and/or academic arguments underpin it. / AFRIKAANSE OPSOMMING: Die Suid-Afrikaanse besigheidsarena skep 'n ryk platform vir tersiêre navorsing in strategie bestuur aan nagraadse studente by bestuurskole. Die probleem bestaan egter dat min sodanige gevallestudies opgeteken is en derhalwe beskikbaar is as leerstof. Die navorser dra by wyse van hierdie werkstuk by tot die uitgedunde bron van leermateriaal beskikbaar vir strategiese analises van Suid-Afrikaanse gevallestudies. Die gekose maatskappy vir analise, is Pick 'n Pay Stores Limited. Hierdie maatskappy is tipies 'n leier in die kleinhandel voedsel industrie. Daar is baie inligting beskikbaar en opgeteken aangaande hierdie maatskappy, wat die leerervaring vir die student vergroot. Die werkstuk word opgeskryf in die vorm van 'n gevallestudie wat die student noop om , deur die leesstof te werk en die opgestelde vrae te beantwoord. Die vrae is geformuleer met die doel om die student deur die logiese stappe van 'n strategiese analise van 'n maatskappy te lei. Die gevallestudie sluit ook 'n modelantwoord in wat ten doel het om die dosent te lei in die antwoorde wat verwag word in die gevallestudie. Die student word aanvanklik voorgestel aan 'n model wat gebruik kan word in 'n tipiese strategiese analise van 'n maatskappy. Hierdie model dien as raamwerk vir die strategiese analise van Pick 'n Pay. Die student word uitgenooi om hierdie model te gebruik om die strategiese analise van die maatskappy te doen. In soverre hierdie model nie voldoende is nie, kan die student 'n nuwe model bekend stel, solank dit met weldeurdagte akademiese en/of besigheidsbeginsels onderstreep word.

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