Dissertations / Theses on the topic 'FPW'
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Matthews, Glenn Ian, and gimatthews@ieee org. "Investigation of Flexural Plate Wave Devices for Sensing Applications in Liquid Media." RMIT University. Electrical and Computer Engineering, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20090219.120815.
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In this thesis, the author proposes and presents a novel simulation technique for the analysis of multilayered Flexural Plate Wave (FPW) devices based on the convergence of the Finite Element method (FEM) with classical Surface Acoustic Wave (SAW) analysis techniques and related procedures. Excellent agreement has been obtained between the author's approach and other more conventional modelling techniques. Utilisation of the FEM allows the performance characteristics of a FPW structure to be critically investigated and refined before undertaking the costly task of fabrication. Based on a series of guidelines developed by the author, it is believed the proposed technique can also be applied to other acoustic wave devices. The modelling process developed is quite unique as it is independent of the problem geometry as verified by both two and three dimensional simulations. A critical review of FEM simulation parameters is presented and their effect on the frequency domain response of a FPW transducer given. The technique is also capable of simultaneously modelling various second-order effects, such as triple transit, diffraction and electromagnetic feedthrough, which often requires the application of several different analysis methodologies. To verify the results obtained by the author's novel approach, several commonly used numerical techniques are discussed and their limitations investigated. The author initially considers the Transmission Matrix method, where it is shown that an inherent numerical instability prevents solution convergence when applied to large frequency-thickness products and complex material properties which are characteristic of liquids. In addition the Stiffness Matrix method is investigated, which is shown to be unconditionally stable. Based on this technique, particle displacement profiles and mass sensitivity are presented for multilayered FPW structures and compared against simpler single layer devices commonly quoted in literature. Significant differences are found in mass sensitivity between single layer and multilayered structures. Frequency response characteristics of a FPW device are then explored via a spectral domain Green's function, which serves as a further verification technique of the author's novel analysi s procedure. Modifications to the spectral domain Green's function are discussed and implemented due to the change in solution geometry from SAW to FPW structures. Using the developed techniques, an analysis is undertaken on the applicability of FPW devices for sensing applications in liquid media. Additions are made to both the Stiffness Matrix method and FEM to allow these techniques to accurately incorporate the influence of a liquid layer. The FEM based approach is then applied to obtain the frequency domain characteristics of a liquid loaded FPW structure, where promising results have been obtained. Displacement profiles are considered in liquid media, where it is shown that a tightly coupled Scholte wave exists that is deemed responsible for most reported liquid sensing results. The author concludes the theoretical analysis with an in-depth analysis of a FPW device when applied to density, viscosity and mass sensing applications in liquid media. It is shown that a single FPW device is potentially capable of discriminating between density and viscosity effects, which is typically a task that requires a complex and costly sensor array.
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Akella, Sriram. "Design and test of lead-zirconate-titanate flexural plate wave based actuators." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001001.
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Paplewski, Peter. "Instabile Halogenphosphane FPO, FPS und PH2Br Erzeugung und rotationsschwingungs- spektroskopische Charakterisierung /." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=964164310.
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Al-Mashat, Alex. "Comparison of Multiple Models for Diabetes Using Model Averaging." Thesis, Uppsala universitet, Institutionen för farmaci, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-448168.
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Pharmacometrics is widely used in drug development. Models are developed to describe pharmacological measurements with data gathered from a clinical trial. The information can then be applied to, for instance, safely establish dose-response relationships of a substance. Glycated hemoglobin (HbA1c) is a common biomarker used by models within antihyperglycemic drug development, as it reflects the average plasma glucose level over the previous 8-12 weeks. There are five different nonlinear mixed-effects models that describes HbA1c-formation. They use different biomarkers such as mean plasma glucose (MPG), fasting plasma glucose (FPG), fasting plasma insulin (FPI) or a combination of those. The aim of this study was to compare their performances on a population and an individual level using model averaging (MA) and to explore if reduced trial durations and different treatment could affect the outcome. Multiple weighting methods were applied to the MA workflow, such as the Akaike information criterion (AIC), cross-validation (CV) and a bootstrap model averaging method. Results show that in general, models that use MPG to describe HbA1c-formation on a population level could potentially outperform models using other biomarkers, however, models have shown similar performance on individual level. Further studies on the relationship between biomarkers and model performances must be conducted, since it could potentially lay the ground for better individual HbA1c-predictions. It can then be applied in antihyperglycemic drug development and to possibly reduce sample sizes in a clinical trial. With this project, we have illustrated how to perform MA on the aforementioned models, using different biomarkers as well as the difference between model weights on a population and individual level.
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Ivaškevičius, Klaidas. "Daugiamačių sekų šablonų analizė." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2012~D_20140630_173416-93518.
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Pagrindinis šio magistro baigiamojo darbo tikslas buvo apžvelgti kai kurių algoritmų ir jų kombinacijų pritaikymą daugiamačiams sekų šablonams analizuoti ir įgyvendinti algoritmą, gebantį tai atlikti. Buvo aprašyta FP-Tree medžio struktūra, kuri yra skirta kompaktiškai saugoti kritiniams (pvz., dažnai pasikartojantiems) duomenims, pateiktas FP-Growth algoritmas, galintis analizuoti tokią duomenų struktūrą ir rezultate pateikiantis visų dažnų elementų šablonų aibę. Pristatyta modifikuotų FP-Growth ir PrefixSpan algoritmų kombinacija – MD-PS-FPG algoritmas, pateikti kai kurių atliktų testavimų rezultatai, tolimesnių darbų pagrindiniai tikslai ir pan.The main goal of this master final work was to present some of the algorithms and their combinations for the multidimensional sequence pattern mining and implement an algorithm, that is capable of doing that. FP-Tree, that is used to store critical (for example, often repeated) data, was described. FP-Growth algorithm, that can analyze FP-Tree structure and give frequent pattern set as a result, was presented. MD-PS-FPG algorithm – a combination of modified FP-Growth and PrefixSpan algorithms – was introduced. The results of some tests, further work objectives and other things were also presented.
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Strohmann, Thomas. "Very sparse kernel models: Predicting with few examples and few features." Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3239405.
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Ali, Khaled Yousif. "Friction Stir Welding Between Similar and Dissimilar Materials." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1513857047779233.
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Junior, Marcos de Freitas. "Melhoria na consistência da contagem de pontos de função com base na Árvore de pontos de função." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/100/100131/tde-02022016-012253/.
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Análise de Pontos de Função (APF) é uma das medidas usadas para obter o tamanho funcional de um software. Determinou-se, no Brasil, que toda contratação pública de desenvolvimento de software deve usar APF. Entretanto, uma das principais críticas realizadas a APF diz respeito à falta de confiabilidade entre diferentes contadores em uma mesma contagem já que, segundo alguns pesquisadores, as regras de APF são subjetivas, obrigando que cada contador faça interpretações individuais a partir delas. Existem diversas propostas para que se possa aumentar a confiabilidade dos resultados gerados com APF. Em geral, as abordagens propostas realizam mapeamentos entre componentes de artefatos desenvolvidos no ciclo de vida de software com os conceitos de APF. Porém, tais propostas simplificam em mais de 50% as regras previstas em APF comprometendo a validade dos resultados gerados pelas contagens. Como o tamanho do software é usado na derivação de outras medidas, inconsistências nos tamanhos medidos podem comprometer as medidas derivadas, o que influência negativamente nas decisões tomadas. Sem padronização dos tamanhos funcionais obtidos e consequentemente sem confiabilidade dos resultados obtidos, medidas derivadas a partir do tamanho funcional, como custo e esforço, podem estar comprometidas, fazendo com que ela não ajude a influenciar positivamente tais projetos. Diante desse contexto, o objetivo deste trabalho é desenvolver e avaliar experimentalmente uma abordagem para oferecer maior padronização e sistematização na aplicação de APF. Para isso, propõe-se incorporar o artefato Árvore de pontos de função ao processo de APF. Sua inclusão possibilitaria o levantamento de dados adicionais, necessários à contagem de pontos de função, reduzindo a ocorrência de interpretações pessoais do contador, e consequentemente, a variação de tamanho reportado. A abordagem foi denominada como Análise de Pontos de Função baseada em Árvore de Pontos de Função (APF-APF). Este trabalho baseia-se no método de pesquisa Design Science, cujo objetivo é estender os limites do ser humano e as capacidades organizacionais, criando novos artefatos que solucionem problemas ainda não resolvidos ou parcialmente resolvidos; que neste trabalho, trata-se da falta de confiabilidade na aplicação de APF devido à sua margem para diferentes interpretações. APF-APF foi testada com 11 Analistas de Sistemas / Requisitos que, baseados na especificação de um software de Recursos Humanos medido oficialmente pelo IFPUG com 125 pontos de função, modelaram a Árvore de pontos de função de modo manual ou automatizado via protótipo de ferramenta desenvolvido. Os resultados obtidos indicam que os tamanhos funcionais calculados com APF-APF possuem coeficiente de variação, respectivamente de 10,72% em relação a confiabilidade e 17,61% em relação a validade dos resultados de medição gerados. Considera-se que a abordagem APF-APF mostrou potencial para que melhores resultados possam ser obtidos. Verifica-se que a principal causa das variações observadas estava relacionada a ausência de informações requeridas para a Árvore de pontos de função, não tendo sido identificado nenhum problema específico em relação as regras definidas para APF-APF. Por fim, verificou-se que o uso do protótipo de ferramenta desenvolvido aumenta em até 47% a eficiência na contagem de pontos de função quando comparado com APF-APF manualFunction point analysis (FPA) is one of the measures used to achieve the functional size of software. It was determined, in Brazil, public procurement of software development should use FPA. However, one of the main criticisms made the FPA concerns the lack of reliability between different counters on the same count that, according to some researchers, the FPA rules are subjective, requiring that each counter do individual interpretations from them. There are various proposals in order to increase the reliability of the results generated with FPA. In General, the proposed approaches perform mappings between artifacts developed components in software life cycle with the concepts of FPA. However, such proposals simplify in more than 50% the rules laid down in FPA compromising the validity of the results generated by the scores. As the size of the software is used in the derivation of other measures, inconsistencies in sizes measured may compromise the measures derived, which negatively influence the decisions taken. Without standardization of functional sizes obtained and consequently without reliability of the results obtained, derived from measures of functional size, cost and effort, may be compromised, causing it to not help to positively influence these projects. In this context, the objective of this work is to develop and experimentally evaluate one approach to offer greater standardization and systematization in the implementation of FPA. For this, it is proposed to incorporate the artifact \"function point Tree\" to the FPA process. Its inclusion would allow additional data collection necessary for function point count, reducing the occurrence of personal interpretations of the counter, and consequently, the variation of size reported. The approach was called as Function Point Tree-based Function Point Analysis (FPT-FPA). This work is based on the method of Design Science research, whose goal is to extend the limits of the human and organizational capacities, creating new artifacts to troubleshoot unresolved or still partially resolved; in this work, it is the lack of reliability in application of FPA because of its scope for different interpretations. FPT-FPA were tested with 11 Systems analysts / requirements analysts, based on the specification of a human resources software measured by the IFPUG with 125 points, have modeled the function point Tree manually or via automated tool prototype developed. The results obtained indicate that the functional sizes calculated with FPT-FPA have coefficient of variation, respectively of 10.72% for reliability and 17.61% in relation to the validity of the measurement results generated. The FPA approach showed potential for better results can be obtained. It turns out that the main cause of the variations observed were related to the absence of information required for the tree of function points have not been identified any particular problem regarding the rules defined for FPT-FPA. Finally, it was found that the use of a prototype tool increases by up to 47% on efficiency function point count when compared to FPT-FPA manual
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Tomblin, Josh. "Buried FPR-Concrete Arches." Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/TomblinJX2006.pdf.
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Read, Ian James. "Few moded fibre systems." Thesis, University of Kent, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282488.
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Fifelski, Constance J. "A few bold women." Online full text .pdf document, available to Fuller patrons only, 2002. http://www.tren.com.
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Soares, João Paulo da Conceição. "FEW phone file system." Master's thesis, FCT - UNL, 2009. http://hdl.handle.net/10362/2229.
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Trabalho apresentado no âmbito do Mestrado em Engenharia Informática, como requisito parcial para obtenção do grau de Mestre em Engenharia InformáticaThe evolution of mobile phones has made these devices more than just simple mobile communication devices. Current mobile phones include such features as built-in digital cameras, the ability to play and record multimedia contents and also the possibility of playing games. Most of these devices have support for Java developed applications, as well as multiple wireless technologies (e.g. GSM/GPRS, UMTS, Bluetooth, and Wi-Fi). All these features have been made possible due to technological evolution that led to the improvement of computational power, storage capacity, and communication capabilities of these devices. This thesis presents a distributed data management system, based on optimistic replication,named FEW Phone File System. This system takes advantage of the storage capacity and wireless communication capabilities of current mobile phones, by allowing users to carry their personal data “in” their mobile phones, and to access it in any workstation, as if they were files in the local file system. The FEW Phone File System is based on a hybrid architecture that merges the client/server model with peer-to-peer replication, that relies on periodic reconciliation to maintain consistency between replicas. The system’s server side runs on the mobile phone, and the client on a workstation. The communication between the client and the server can be supported by one of multiple network technologies, allowing the FEW Phone File System to dynamically adapt to the available network connectivity. The presented system addresses the mobile phone’s storage and power limitations by allowing multimedia contents to be adapted to the device’s specifications, thus reducing the volume of data transferred to the mobile phone, allowing for more user’s data to be stored. The FEW Phone File System also integrates mechanisms that maintain information about the existence of other copies of the stored files (e.g. WWW), avoiding the transfer of those files from the mobile device whenever accessing those copies is advantageous. Due to the increasing number of on-line storage resources (e.g. CVS/SVN, Picasa), this approach allows for those resources to be used by the FEW Phone File System to obtain the stored copies of the user’s files.
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Reese, Gregory A. "Dissimilar Friction Stir Welding Between Magnesium and Aluminum Alloys." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc955097/.
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Joining two dissimilar metals, specifically Mg and Al alloys, using conventional welding techniques is extraordinarily challenging. Even when these alloys are able to be joined, the weld is littered with defects such as cracks, cavities, and wormholes. The focus of this project was to use friction stir welding to create a defect-free joint between Al 2139 and Mg WE43. The stir tool used in this project, made of H13 tool steel, is of fixed design. The design included an 11 mm scrolled and concave shoulder in addition to a 6 mm length pin comprised of two tapering, threaded re-entrant flutes that promoted and amplified material flow. Upon completion of this project an improved experimental setup process was created as well as successful welds between the two alloys. These successful joints, albeit containing defects, lead to the conclusion that the tool used in project was ill fit to join the Al and Mg alloy plates. This was primarily due to its conical shaped pin instead of the more traditional cylindrical shaped pins. As a result of this aggressive pin design, there was a lack of heat generation towards the bottom of the pin even at higher (800-1000 rpm) rotation speeds. This lack of heat generation prohibited the material from reaching plastic deformation thus preventing the needed material flow to form the defect free joint.
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Wolczuk, Dan. "Intervals with few Prime Numbers." Thesis, University of Waterloo, 2004. http://hdl.handle.net/10012/1064.
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In this thesis we discuss some of the tools used in the study of the number of primes in short intervals. In particular, we discuss a large sieve density estimate due to Gallagher and two classical delay equations. We also show how these tools have been used by Maier and Stewart and provide computational data to their result.
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Mujal, Torreblanca Pere. "Interacting ultracold few-boson systems." Doctoral thesis, Universitat de Barcelona, 2019. http://hdl.handle.net/10803/668191.
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In this thesis, we study the physical properties of several ultracold few-boson systems depending on the interactions between their constituents. Nowadays, experimentally, it is possible to have great control with high precision over the geometry and the interactions between the particles, making them an excellent setup to test directly the principles of quantum mechanics. A very interesting point is to study the evolution of their properties with the number of particles. The theoretical study of these systems pretends to microscopically understand the current experimental results and give support to new experimental developments.
The method that will be used is the exact diagonalization of the Hamiltonian of the system. As we will see, in spite of the attempts to improve it, the method is limited by the fact that, in practice, it is only useful to study few-particle systems. The method has several advantages. First of all, one has access to both the ground and the excited states. In second place, the method is variational and converges to the exact solution as long as the Hilbert space in which we diagonalize is enlarged.
Moreover, since we have access to the states of the system, it is possible to calculate any observable quantity of interest.
First, we will study a system of spinless bosons trapped in a two-dimensional harmonic potential. The effect of the trap is to keep the system bound. It will be seen how the presence of a repulsive interaction changes the energy spectrum and other properties of the system. For instance, the density profile, which is usually measurable, and also the two-body distribution function, which is intimately related to the existence of correlations.
Afterwards, the focus will be on the particular case of having only two bosons in the system interacting through a strong repulsive force. Inspired by the one-dimensional case where the fermionization phenomenon takes place in the strongly-interacting limit, we will study whether in two dimensions there is a resembling reminiscent effect. In other words, we will analyze if there are properties of the two strongly-interacting bosons in two dimensions that are like the ones of two noninteracting fermions.
After that, we will tackle the localization phenomenon in a one-dimensional system that is caused by an external speckle potential that introduces disorder in the system. We will show that the localization is a robust phenomenon against repulsive contact interactions.
Finally, we will study the influence of the spin-orbit coupling in a system of bosons with two possible pseudospin components, associated, for instance, to two hyperfine levels, confined in a two-dimensional harmonic trap. We will present an exhaustive analysis of the combined effects of the interaction and the spin-orbit coupling in the spectrum and the properties of the system. In particular we show the existence of a crossover in the ground state of the system susceptible to be experimentally identified.En aquesta tesi, estudiarem les propietats físiques de diversos sistemes de pocs bosons ultrafreds depenent de les interaccions entre els seus constituents. Avui dia, a nivell experimental, es té un gran control amb una gran precisió de la geometria i les interaccions entre les partícules, fet que fa aquest sistemes excel·lents per comprovar de forma directa els principis de la mecànica quàntica. Un punt d'interès és comprovar l'evolució de les seves propietats amb el nombre de partícules. L'estudi teòric d'aquests sistemes pretén entendre a nivell microscòpic els resultats experimentals actuals i donar suport pels nous avenços experimentals. El mètode que farem servir serà la diagonalització exacta del hamiltonià del sistema. Com veurem, malgrat les millores que es poden implementar, ens trobarem amb la limitació de no poder estudiar sistemes de més d'unes quantes partícules. Els avantatges d'aquest mètode són diversos. En primer lloc, podrem obtenir no només l'estat fonamental del sistema sinó que també els primers estats excitats. En segon lloc, el mètode és variacional i sabem que convergeix cap a la solució exacta a mesura que ampliem l'espai de Hilbert en que diagonalitzem. A més a més, en tenir accés als estats del sistema, podem calcular qualsevol quantitat observable que sigui d'interès. Primerament, estudiarem un sistema de bosons sense espín atrapats en un potencial harmònic bidimensional. L'efecte de la trampa és de mantenir el sistema lligat. En haver-hi una interacció repulsiva, veurem com canvia l'espectre d'energia del sistema i també altres propietats. Per exemple, la seva densitat, que habitualment es pot mesurar, i també la funció de distribució de dos cossos, que va íntimament lligada a l'existència de correlacions. Tot seguit, ens centrarem en el cas particular de tenir només dos bosons en el sistema interaccionant a través d'una gran força repulsiva. Inspirats pel cas unidimensional en que té lloc el fenomen de la fermionització en el limit d'interacció molt forta, estudiarem si en el cas bidimensional hi queda cap reminiscència d'aquest efecte. En altres paraules, analitzarem si hi ha propietats dels dos bosons fortament interactuants en dues dimensions que siguin com les de fermions no interactuants en el mateix sistema. A continuació, tractarem el fenomen de la localització en un sistema unidimensional en el qual hi ha un potencial extern de tipus speckle que introdueix desordre en el sistema. Veurem que la localització és un fenomen robust en front de les interaccions repulsives. Per últim, estudiarem la influència de l'espín-òrbita en un sistema de bosons amb dues components de pseudoespín, associades, per exemple, a dos nivells hiperfins, atrapats en un potencial harmònic bidimensional. Presentarem un anàlisi exhaustiu dels efectes conjunts de la interacció i l'espín- òrbita en l'espectre i en les propietats del sistema. En particular, mostrarem l'existència d'un encreuament en l'estat fonamental del sistema susceptible de ser identificat experimentalment.
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Sakhr, Jamal Bhaduri Rajat K. "The semiclassical few-body problem /." *McMaster only, 2003.
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Bultena, Albertha. "Venn diagrams with few intersections." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0002/MQ36611.pdf.
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Ramirez, Lourdes Patricia. "Few-cycle OPCPA laser chain." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00806245.
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The Apollon-10 PW laser chain is a large-scale project aimed at delivering 10 PW pulses to reach intensities of 10^22 W/cm^2. State of the art, high intensity lasers based solely on chirped pulse amplification (CPA) and titanium sapphire (Ti:Sa) crystals are limited to peak powers reaching 1.3 PW with 30-fs pulses as a result of gain narrowing in the amplifiers. To access the multipetawatt regime, gain narrowing can be suppressed with an alternative amplification technique called optical parametric chirped pulse amplification (OPCPA), offering a broader gain bandwidth and pulse durations as short as 10 fs. The Apollon-10 PW laser will exploit a hybrid OPCPA-Ti:Sa-CPA strategy to attain 10-PW pulses with 150 J and 15 fs. It will have two high-gain, low-energy amplification stages (10 fs ,100 mJ range) based on OPCPA in the picosecond and nanosecond timescale and afterwards, and will use Ti:Sa for power amplification to the 100-Joule level.Work in this thesis involves the progression of the development on the Apollon-10 PW front end and is focused on the development of a high contrast, ultrashort seed source supporting 10-fs pulses, stretching these pulses prior to OPCPA and the implementation of the picosecond OPCPA stage with a target of achieving 10-mJ pulses and maintaining its bandwidth. To achieve the final goal of 15-fs, 150-J pulses, the seed source must have a bandwidth supporting 10-fs and a temporal contrast of at least 10^10. Thus from an initial commercial Ti:Sa source delivering 25-fs pulses with a contrast of 10^8, spectral broadening via self-phase modulation and contrast enhancement with cross polarized (XPW) generation was performed. Subsequently, the seed pulses were stretched to a few picoseconds to match the pump for picosecond OPCPA. Strecher designs using an acousto-optic programmable dispersive filter (dazzler) for phase control in this purpose are studied. A compact and straightforward compressor using BK7 glass is used and an associated compressor for pulse monitoring was also studied. Lastly, the picosecond OPCPA stage was implemented in single and dual stage configurations.
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Cavrini, Guido. "Il ruotamento nelle configurazioni FPL." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8767/.
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La Congettura di Razumov-Strogranov, dimostrata solo nel 2010 con metodi puramente combinatori da due matematici italiani, Contini e Sportiello, ha affascinato molti studiosi di combinatoria che si sono dedicati allo studio delle configurazioni FPL. In questa tesi viene studiato il ruotamento, una speciale permutazione delle configurazioni FPL con determinate condizioni al bordo che è lo strumento fondamentale per la dimostrazione della sovramenzionata congettura.
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Dobiášková, Veronika. "Strategie rozvoje podniku FPO s.r.o." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2010. http://www.nusl.cz/ntk/nusl-222495.
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This diploma thesis is dealing with creating compact description of strategic documentation in a company. It helps to set one direction, where the company should be heading in its vision, function, identity, objectives and values. It is a compact collection for strategic development of the company and for keeping the direction towards the chosen objectives set beforehand. It is possible to secure coordination and mutual belonging of the parts and objective of the company in a framework of unanimous material.
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Cherry, Donna J., and John G. Orme. "The Vital Few Foster Mothers." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/7640.
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Many foster parents serve only briefly, and foster and adopt few children. Anecdotal reports suggest that a small percentage of foster parents provide a disproportionate amount of care; however, we know virtually nothing about these parents. This study applied the Pareto Principle, also known as the 80-20 rule or Vital Few, as a framework to conceptualize these foster parents. Using latent class analysis, two classes of mothers were identified: one accounted for 21% of mothers and the other 79%. We refer to the former as the Vital Few and the latter as the Useful Many. Vital Few mothers fostered 73% of foster children - 10 times more than Useful Many mothers although only fostering three times longer. They adopted twice as many foster children while experiencing half the yearly rate of placement disruptions. Vital Few mothers were less likely to work outside the home, had better parenting attitudes, more stable home environments, more time to foster, and more professional support for fostering, but less support from kin. Further, they were as competent as the Useful Many on numerous other psychosocial measures. Understanding characteristics of these resilient Vital Few can inform recruitment and retention efforts and offer realistic expectations of foster parents.
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Closa, Calvo Marta. "Estudi de l'especialització funcional dels isoenzims citosòlics de la farnesildifosfat sintasa d'Arabidopsis thaliana." Doctoral thesis, Universitat de Barcelona, 2007. http://hdl.handle.net/10803/1054.
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Les farnesildifosfat sintases (FPS) catalitzen la condensació de dues molècules d'isopentenildifosfat (IPP) amb una molècula de dimetilal.lildifosfat (DMAPP) per produir farnesildifosfat (FPP; C15). Tant els substrats com el producte de la reacció catalitzada per les FPS ocupen una posició molt important en la via del mevalonat de síntesi d'isoprenoides, ja que són punt de partida de nombroses ramificacions cap a la síntesi de diversos productes finals. A Arabidopsis thaliana existeix una petita família multigènica integrada pels gens FPS1 i FPS2, que codifiquen tres isoenzims FPS: FPS1S, FPS1L i FPS2. L'isoenzim FPS1L conté un pèptid de trànsit que li confereix una localització mitocondrial, mentre que FPS1S i previsiblement FPS2, tenen una localització citosòlica. A l'inici d'aquest treball, s'havien clonat els gens FPS1 i FPS2, i s'havien definit els seus patrons d'expressió espaial i temporal mitjançant l'anàlisi de plantes transgèniques portadores de gens quimèrics formats pels promotors d'ambdós gens fusionats al gen reporter uidA d'E. Coli. També s'havia estudiat el paper dels isoenzims FPS1S i FPS1L en la via del mevalonat a través de la caracterització de plantes transgèniques que sobreexpressaven aquests isoenzims. La localització de l'isoenzim FPS1L a les mitocòndries ja és, en sí mateixa, una evidència d'especialització funcional. En el cas dels isoenzims FPS1S i FPS2, el fet de pensar en l'existència d'una especialització funcional deriva dels seus patrons d'expressió diferencials.Amb l'objectiu d'analitzar el paper de l'isoenzim FPS2 en la via del mevalonat, i obtenir evidències de l'especialització funcional dels isoenzims FPS1S i FPS2, en aquesta tesi es duen a terme diferents abordatges experimentals basats en l'obtenció i caracterització de mutants d'A. Thaliana amb guany i pèrdua de funció dels gens FPS1 i FPS2. Per una banda, mitjançant l'estudi dels efectes de la sobreexpressió de l'isoenzim FPS2 i de la sobreexpressió simultània dels isoenzims FPS1S i FPS2. D'altra banda, a través de l'anàlisi de mutants amb pèrdua de funció dels gens FPS1 i FPS2 i del doble mutant fps1:fps2. Aquests abordatges es complementen amb l'estudi dels efectes de la sobreexpressió en A. Thaliana de proteïnes quimèriques FPS1S/FPS2 (domain swapping), l'elaboració de models estructurals tridimensionals dels isoenzims FPS1S i FPS2 i l'anàlisi dels perfils d'expressió gènica en mutants amb pèrdua de funció dels isoenzims FPS.
En aquest treball es demostra que els isoenzims FPS1S i FPS2, tot i catalitzar la síntesi del mateix producte, tenir la mateixa localització subcel.lular i uns paràmetres cinètics similars, produeixen efectes molt diferents quan són sobreexpressats en A. thaliana. La presència d'un únic isoenzim FPS és suficient per garantir la viabilitat de les plantes, ara bé, la pèrdua de funció de l'isoenzim FPS2 desencadena una resposta metabòlica compensatòria a les llavors. En conjunt, tots els resultats indiquen que els isoenzims citosòlics FPS1S i FPS2 desenvolupen funcions majoritàriament redundants, tot i que presenten una certa especialització funcional que sembla derivar del patró d'expressió especialitzat de cadascun dels gens FPS.
Farnesyldiphosphate synthases (FPS) catalyze the condensation of two molecules of isopentenyldiphosphate (IPP) with its isomer dimethylallyldiphosphate (DMAPP) to produce farnesyldiphosphate (FPP; C15). FPS is located at a key position in the mevalonic acid pathway (MVA), as both the substrates and the reaction product are precursors of a variety of isoprenoid end-products. Arabidopsis thaliana contains a small FPS gene family consisting of two genes, FPS1 and FPS2, encoding three FPS isoforms: FPS1S, FPS1L and FPS2. FPS1L isoform is located in the mitochondria, whereas FPS1S and likely FPS2, are both localized in the cytosol. The differential patterns of expression of FPS1 and FPS2, strongly suggest a functional specialization of the encoded FPS1S and FPS2 isoforms.
The aim of this thesis is to analyze the role of FPS2 isozyme in the MVA pathway and to obtain evidence of a functional specialization of FPS1S and FPS2 isozymes. Different experimental approaches have been undertaken using A. thaliana mutants with gain and loss of function of FPS1S and FPS2. We have investigated the effects of FPS2 overexpression and the effects of the overexpression of both FPS isozymes simultaneously. We have also characterized A. thaliana knock-out mutants in both FPS genes and the double knock-out mutant fps1:fps2. Analysis of the effects caused by the overexpression of chimeric FPS1S/FPS2 proteins in A. thaliana, 3D modelling of FPS isozymes, and microarray analysis of FPS knock-out mutants are also included in this study.
Results demonstrate that, although FPS1S and FPS2 isozymes synthesize the same reaction product, have the same subcellular localization and have similar kinetic parameters, its overexpression produce different effects in A. thaliana. The existence of a single FPS isozyme is enough to assure plant viability. However, FPS2 loss of function triggers a compensatory metabolic response in A. thaliana seeds. All these results indicate that FPS1S and FPS2 play redundant functions in the MVA pathway, although they also show a certain level of functional specialization.
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Bruckner, Dean C. "Automatic pulse shaping with the AN/FPN-42 and AN/FPN-44A Loran-C transmitters." Thesis, Monterey, California : Naval Postgraduate School, 1992. http://handle.dtic.mil/100.2/ADA257860.
Full textAbstract:
Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 1992.Thesis Advisor: Tummala, Murali. "December 1992." Description based on title screen as viewed on April 16, 2009. Includes bibliographical references (p. 181-183). Also available in print.
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Huang, Dong Fang. "Investigation of Heterogeneity of FSW Inconel 718 Coupled with Welding Thermal Cycle." BYU ScholarsArchive, 2008. https://scholarsarchive.byu.edu/etd/1914.
Full textAbstract:
In order to develop a better understanding of the property, microstructure evolution and thermal history of FSW Inconel 718's, the strain, strain rate and thermal cycles need to be determined. In order to estimate the strain field of a deformed body, a displacement function needs to be determined. A 3D deformation model was developed to determine the displacement coefficients. A rectangular box created in this model deforms following a linear displacement function. Three orthogonal planes cut this deformed box, which leads to three deformed planes. The shape parameters (L, H, θ¹ and θ²) on the three orthogonal planes can be expressed as the functions of displacement coefficients. Although the displacement coefficients can not be expressed in the forms of the shape parameters symbolically, a numerical solution can be found using numerical optimization methods. The shape parameters were obtained by assuming the displacement coefficients (three cases). Then, the numerical optimization was carried out to determine the displacement coefficients. The solved displacement coefficients are the same as the assumed ones, which shows that this inverse problem can be solved, and this model is robust to determine the displacement function numerically. This model was used to estimate the strain and strain rate at the boundary of the nugget zone of Friction Stir Welding (FSW) Inconel 718. A numerical/experimental methodology was developed to estimate the thermal history in the stir zone of FSW Inconel 718.The thermocouple experiment was conducted to measure the thermal cycles in Heat Affected Zone (HAZ). Using the measured temperature in HAZ and a numerical model, the peak temperature (1039 ºC) and cooling rate (58.18 ºC/s) were determined. The microstructure in different regions was characterized and co-related with the thermal cycles. In order to understand the microstructure evolution in the stir zone, the strain rate (12.612 s-1) was estimated using the mathematical model as mentioned above. According to the estimated thermal history and strain rate, the assumption that the dynamic recrystallizaiton occurred during FSW was made. The grain size in the nugget zone affects the hardness. The relationship among the microstructure, mechanical properties, and thermal cycles was discussed.
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Autant, Cyril. "Réseaux de Pétri pour la sémantique et l'implémentation de processus parallèles." Phd thesis, Grenoble INPG, 1993. http://tel.archives-ouvertes.fr/tel-00343578.
Full textAbstract:
Dans la première partie de cette thèse, nous présentons une implémentation du langage fp2 ayant pour modèle les réseaux de Petri. Fp2 est un langage de programmation parallèle base sur la réécriture de termes et les spécifications algébriques. Nous donnons une nouvelle sémantique a fp2, de la famille des sémantiques du vrai parallélisme, et prouvons la correction de cette sémantique par rapport a la sémantique interleaving du langage. Le modèle utilise, les réseaux de Petri, et la nouvelle sémantique donnée au langage permettent une représentation plus compacte de programmes complexes, évitant les problèmes d'explosion combinatoire rencontres avec les implémentations précédentes. Nous évaluons le gain de notre approche, et proposons plusieurs schémas d'interprétation du langage, bases sur cette nouvelle sémantique. La seconde partie de ce travail concerne la définition d'une nouvelle famille d'équivalences comportementales pour les réseaux de Petri. Alors que les équivalences proposées jusqu'alors sont définies entre les marquages, c'est-a-dire entre les états globaux du réseau, nous définissons une relation entre les places du réseau, reprenant une idée proposée par olderog. De nouvelles équivalences, les bisimulations de places, sont proposées a partir de cette définition. Un algorithme efficace (polynomial) permettant de calculer la plus grande bisimulation de places sur un réseau est propose. Nous montrons comment simplifier un réseau en le quotientant par cette plus grande bisimulation, obtenant ainsi un représentant canonique d'une classe d'équivalence de réseaux bisimilaires de places. L'étude de ces équivalences est ensuite étendue aux réseaux avec actions internes
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Silero, Rejane Wagner Protzner. "Os quantificadores a few e few: questões de interlíngua e prosódia semântica em corpus de aprendizes." Universidade Federal de Minas Gerais, 2014. http://hdl.handle.net/1843/MGSS-9MQQ4B.
Full textAbstract:
The investigation described here was carried out under the light of what has been done by researchers (GRANGER; TRIBBLE, 1998) who are interested in learner English writing. The main goal was to verify and describe the upper-intermediate Brazilian learners interlanguage, specifically concerning the use of the quantifying expressions a few and few. Data from Br- ICLE, the Brazilian subcorpus of the International Corpus of Learner English (ICLE) was analyzed so as to enable description both on the grammatical level and on the level of semantic prosody. Similarly, data from the Louvain Corpus of Native English Essays (LOCNESS), which was built to be the native equivalent for ICLE, was analyzed and used for comparisons. It was also necessary to resort to the academic section of COCA as another reference corpus in order to describe the way native speakers use the quantifiers being studied. The data from both Br-ICLE and LOCNESS were treated qualitatively, through manual analyses of the expanded context of concordance lines whose node word was few. The following sorts of collocations were identified and compared: the collocations that appeared adequate, that is, compatible with native speakers use; and the ones that appeared inadequate, that is, showing deviations that were further systematized and discussed. The type of inadequacy that received special treatment was the one related to the surfacing of semantic prosody. In the native speakers corpus, the collocation very few was often used to express negative semantic prosody; however, this was not attested in the Br-ICLE, which leads to the understanding that such collocation was underused by the learners in similar contexts. Quantitatively, the results of this research were described in percentages, and the diagnosed underuse was validated through statistical testing. In order to gauge the extent to which the mother tongue influences the expression of semantic prosody in the target language, another corpus, whose size is on a par with Br-ICLE and LOCNESS, was compiled: the Co-RAP, which stands for Corpus of Academic Essays in Portuguese (Brazilian Portuguese). Also, the online platform of Corpus do Português was used for further necessary searches. The conclusion drawn was that, in their writing, Brazilians do not seem to widely use muito poucos(as), which is the correspondent collocation in Portuguese to very few, and this may influence their lexical choices when writing in English. Lastly, following the tenets of Data- Driven Learning (JOHNS, 1994), a classroom activity that encourages the recognition of lexico-grammatical patterns was suggested, and promising pathways to future research were mentioned as well.A pesquisa aqui descrita foi conduzida à luz do que já foi realizado por pesquisadores (GRANGER; TRIBBLE, 1998) que se interessam pela produção escrita de aprendizes de inglês. O objetivo geral foi o de verificar e descrever a interlíngua dos aprendizes brasileiros de inglês em nível intermediário-avançado, especificamente quanto ao uso que eles fazem das expressões quantificadoras a few e few em suas produções escritas. Utilizando os dados do Br-ICLE, subcorpus brasileiro do International Corpus of Learner English (ICLE), foram feitas análises que permitiram vislumbrar esse uso não somente em nível gramatical como também em nível de prosódia semântica. Similarmente, foram analisados dados provenientes do corpus de nativos equivalente ao ICLE, o Louvain Corpus of Native English Essays (LOCNESS) para fins comparativos. Recorreu-se, também, ao COCA acadêmico como outro corpus de referência para a descrição do uso que os nativos fazem dos quantificadores em estudo. Os dados do Br-ICLE e do LOCNESS foram tratados qualitativamente por meio de análises manuais do contexto expandido das linhas de concordância com o nódulo few. Foram identificadas e comparadas colocações que se mostraram adequadas, em consonância com o uso dos nativos, e que se mostraram inadequadas, apresentando desvios que foram sistematizados e comentados. O tipo de inadequação que recebeu tratamento especial foi a concernente à manifestação da prosódia semântica. Foi detectado que no corpus dos nativos houve um considerável número de ocorrências da colocação very few para expressar prosódia semântica negativa, fato não verificado no Br-ICLE, atestando subuso dessa colocação pelos aprendizes. Quantitativamente, os resultados obtidos nesse trabalho foram descritos em porcentagens e o subuso identificado recebeu validação por meio de teste estatístico. A fim de averiguar a extensão da influência da língua materna no uso que os aprendizes fizeram dos quantificadores, especialmente mediante a interface com a prosódia semântica, foi compilado o Corpus de Redações Acadêmicas em Português (Co-RAP), de tamanho semelhante ao Br- ICLE e ao LOCNESS, e também foi utilizado o Corpus do Português (online) para demais consultas. A conclusão foi a de que os falantes brasileiros, em suas produções escritas, não fazem um vasto uso de muito poucos(as), que seria a colocação correspondente a very few, e isso pode interferir em suas escolhas lexicais na língua-alvo. Por fim, foi sugerida, aos moldes dos princípios da Aprendizagem Movida por Dados (JOHNS, 1994), uma atividade que estimula a identificação de padrões léxico-gramaticais para os quantificadores investigados, e também foram sugeridos caminhos para próximas pesquisas.
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Onyeani, Onyema Awa. "The obligation of host states to accord the standard of 'full protection and security' to foreign investments under international investment law." Thesis, Brunel University, 2018. http://bura.brunel.ac.uk/handle/2438/16087.
Full textAbstract:
The analysis of this thesis is to examine whether foreign investors can fully rely on the standard of FPS in BITs for the protection of their investments in the territories of host States which has been mandated to States by international law. This question cannot be answered without giving insights into the content and structure of the origin of FPS standard and adopts a dynamic based-perspective of the interpretation of FPS under VCLT 1969, encompassing the relationship between FPS and CIL. It investigates the tribunals' interpretation of the clause using case laws and literatures to identify and explore the underlying explanatory process behind tribunals' case findings and outcomes. The study examines the critical realism that the obligation of FPS standard does not place absolute liability to a host State, rather the exercise of a reasonable degree of vigilance. It evaluates the controversy surrounding the relationships between FPS and FET, and illuminates on how the two standards may co-evolve which has led to various arbitral tribunals' divergence opinions interpretation of the two principles. The evaluation of the application of FPS to digital assets is dynamic in this research as it addresses the nature of threats investors face globally today over cyber attacks of digital investments. The thesis also emphasis on balancing up investors' rights and obligation, which explains the measures that States can apply to prevent foreign investors from engaging in illegitimate activities. Having look at all these issues, circumstances, and the controversies surrounding FPS standard, the result found is that there is a existence of a gap in this area of the law, that would mean that foreign investors cannot completely rely on the principle of FPS for the protection of their investments in the territories of the host unless this lacunae is properly filled by both the States and arbitral tribunals, especially the tribunals' interpretative meaning of the standard of FPS.
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Dickson, Crispin. "A few aspects of aircraft noise." Licentiate thesis, Stockholm : Teknisk akustik, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4510.
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Pax, Paul Henry 1958. "Few-atom effects in atom optics." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/288794.
Full textAbstract:
Despite the many advances and achievements in the fields of atom optics and atom cooling, there remains a wealth of dynamical detail to be filled in. While the main features of the important phenomena of atomic cooling, trapping and manipulation by electromagnetic fields are well understood, there are interesting subsidiary effects that are worth our attention. An example, which we discuss in Ch. 5 is the discovery that atomic diffusion in optical lattices may not follow the normal diffusion equation. The work reported in this dissertation represents an investigation into possible few-body effects in some atom optical configurations of interest. The effects of indistinguishability, through the exchange force, on atomic diffraction by standing wave light fields is considered in Ch. 2. In Ch. 3, after a brief overview of atomic collisions in light fields, we look at the role that the dipole-dipole interaction might play, again in atomic diffraction. Chapters 4 and 5 are concerned with optical lattices, and lay the ground work for a study of the effect of the dipole-dipole interaction on the dynamics of atoms confined in such lattices.
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Schwarz, Alexander. "Few-cycle phase-stable infrared OPCPA." Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-171942.
Full textAbstract:
Few-cycle laser pulses are an important tool for investigating laser-matter interactions. Apart
from the mere resolution used in time-resolved processes, owing to this approach table-top
sources nowadays can reach the limits of the perturbative regime and therewith enable extreme
nonlinear optics. In the visible domain, femtosecond technology over the last decades has quickly developed, in recent years leading to the routine generation of carrier-envelope phase (CEP) stable few-cycle laser pulses at high energies, using ubiquitous Ti:Sapphire amplifiers.
Near to mid-infrared few-cycle pulses in contrast can be employed for investigating interactions
in the tunneling regime. The ponderomotive potential of the infrared light field allows quivered charged particles to acquire large energies, leading to applications like the generation of isolated attosecond pulses in the water window. In this wavelength regime however, the required sources are yet to be demonstrated or at least matured. The best candidate for few-cycle pulses in this domain is optical parametric amplification.
This work describes the development of an optical parametric chirped pulse amplifier (OPCPA),
used to create CEP-stable few-cycle pulses in the near infrared (NIR). It covers all essential parts of the system. First the signal pulses are generated from ultrashort lasers using spectral broadening techniques in chapter 2. After compression of these white light continua, intra-pulse broadband difference frequency generation yields CEP stable infrared
pulses spanning over more than one octave.
A thin-disk-based pump laser provides ample pump energy (20 mJ) at pulse durations around
1.5 ps. Its characterization and optimization for OPCPA is performed in chapter 3. The high
peak energy of this pump laser leads to the buildup of optical nonlinearities and consequently
shows distinct influence on the OPCPA system performance.
The synchronization of the OPCPA pump and seed laser system is the topic of chapter 4. This
chapter is not limited to NIR systems, but demonstrates enhanced (actively stabilized) synchronization of the jitter between pump and seed pulses to σ = 24 fs, which later results in improved output stability.
The NIR OPCPA centered at 2.1 μm is described in chapter 5. This combines the efforts of
the previous chapters and describes the generation and characterization of 100 μJ sub-two-cycle CEP-stable pulses, the shortest published to date at this energy level.
As a first prototype (cutting edge) experiment, CEP dependent sub-fs currents in a dielectric are
generated in chapter 6 using the developed light source. The results compared well to visible
few-cycle laser sources and demonstrate the usability of the OPCPA system (beyond the charac-
terizations of chapter 5) for investigating sub-cycle carrier dynamics in dielectrics.
For the same purpose, to generate the currently most broadband NIR continua at kHz repetition
rates and mJ-level pulse energies, the OPCPA system is further boosted and efficiently broadened to three optical octaves using a hollow core fiber setup (described in chapter 7). The spectral phase is characterized and demonstrates self-compression in the NIR around 1.3 μm. The process provides CEP-stable sub-2-cycle pulses in this regime directly, the shortest and most powerful reported to date.
Furthermore, the spectral broadening in the infrared shows enhanced low-order harmonic gen-
eration and cross-phase-modulation as the dominant mechanism. Experimentally the limited
influence on the driver bandwidth is investigated. It is found that the processes allow using more efficient many-cycle infrared sources to generate several-octave spanning, compressible continua in the future. Even partial compression of these would then provide NIR transients for high-field experiments.Die Femtosekunden-Technologie hat sich in den letzten Jahrzehnten schnell fortentwickelt, vor allem im sichtbaren Wellenl ̈angen-Bereich. Speziell moderne Titanium-Saphir Verst ̈arker haben zuletzt zu (Träger-Einhüllenden-) phasenstabilen und hochenergetischen Laserpulsen geführt, die nur noch aus einzelnen optischen Zyklen bestehen. Diese erlauben die Investigation extrem nichtlinearer optischer Prozesse im Regime der Multiphotonenionisation. Um weiter im Infraroten Prozesse im Regime der Tunnelionisation zu untersuchen, fehlt es jedoch nach wie vor an Lichtquellen mit ähnlichen Characteristiken für Anwendungen wie die Generation von isolierten Attosekunden-Pulsen im Wasser-Transmissions-Fenster. Hier bietet die optische parametrische Verstärkung bisher die größten Perspektiven. Diese Arbeit beschäftigt sich mit der Entwicklung eines optischen parametrischen Verstärkers mit gestreckten Pulsen (engl.: optical parametric chirped pulse amplifier, OPCPA), der TE- phasen-stabile Pulse mit wenigen optischen Zyklen im nahen Infraroten erzeugt. Alle wesentlichen Teile des Systems werden beschrieben. Zuerst wird der Saat-Puls durch die spektrale Verbreiterung eines Titanium-Saphir Verstärkers gewonnen. Nach der Kompression des generierten Weißlichts führt die breitbandige Differenz-Frequenz-Generation (DFG) des Pulses mit sich selbst zu TE-phasen-stabilen Infrarot-Pulsen, deren Spektrum mehr als eine optische Oktave aufspannt. Ein Scheiben-Laser liefert die Pumpenergie (20 mJ) bei einer Pulsdauer von ca. 1.5 ps. Seine Charakterisierung und Optimierung für die OPCPA erfolgt in Kapitel 3. Die hohen Spitzeninten- sit ̈aten dieses Pumplasers führen zum Akkumulieren optischer Nichtlinearit ̈aten und beeinflussen die OPCPA im Folgenden negativ. Die Synchronisation von OPCPA Pump- und Saat-Lasern ist das Thema von Kapitel 4. Es demonstriert eine aktive Stabilisierung des zeitlichen Überlapps beider Pulse, der den gesamten Prozess im Folgenden stabilisiert, und ist nicht auf den Einsatz im Infraroten beschränkt, sondern für die meisten OPCPA Systeme anwendbar. Die in Kapitel 5 beschriebene infrarote OPCPA hat ihre Zentralwellenlänge bei 2.1 μm und baut auf den vorherigen Kapiteln auf. Die Erzeugung und Charakterisierung von Pulsen mit weniger als zwei optischen Zyklen, den bisher kürzesten in diesem Wellenlängen-Bereich und einer En- ergie von 100 μJ, werden beschrieben. Ferner erweist sich die TE-Phase der verstärkten Pulse als außerordentlich kurz- und langzeitstabil. Kapitel 6 demonstriert dann die Möglichkeiten des neuen Systems mit einem technisch anspruchsvollen Experiment. TE-phasen-abhängige Ströme mit einer Lebenszeit auf der Skala von Attosekunden werden in einem Dielektrikum erzeugt und gemessen. Die Resultate stimmen gut mit den bere- its gemessenen Werten im sichtbaren Bereich u ̈ berein und demonstrieren die Möglichkeiten und Einsetzbarkeit des Systems. Für ähnliche Anwendungen, allerdings bei noch höheren Intensitäten, wird in Kapitel 7 das OPCPA-System weiter verstärkt. Die spektrale Verbreiterung in einer gas-gefüllten Hohlfaser erzeugt ein Kontinuum über drei optische Oktaven. Dessen spektrale Phase wird im Folgen- den charakterisiert und zeigt Selbstkompression bei einer Wellenlänge von 1.3 μm. Der Prozess erzeugt TE-phasen-stabile Pulse kürzer also zwei optische Zyklen, welche die kürzesten und intensivsten darstellen, die in diesem Bereich bislang erzeugt wurden. Weiterhin zeigt die spektrale Verbreiterung im Infraroten besondere Merkmale. Speziell die Gen- eration von ungeraden Harmonischen niedriger Ordnung und deren Kreuz-Phasen-Modulation zeigen sich als dominante Prozesse, welche den Einfluss der Eingangsbandbreite minimieren. Eine experimentelle Untersuchung demonstriert dann, dass auch potentiell effizientere infrarote OPCPA Systeme mit deutlich längeren Pulsen ähnliche spektrale Bandbreiten erzeugen können. Die Komprimierung dieser sollte in der nahen Zukunft zu Hochfeld-Anwendungen mit infraroten Feldtransienten und synthetisierten elektrischen Feldern mit Sub-Zyklus Merkmalen führen.
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Yan, Wenjing. "Spin transport in few-layer graphene." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708038.
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Maheswari, Dhiraj. "QCD Process in Few Nucleon Systems." FIU Digital Commons, 2018. https://digitalcommons.fiu.edu/etd/3795.
Full textAbstract:
One of the important issues of Quantum Chromodynamics (QCD) - the fundamental theory of strong interaction, is the understanding of the role of the quark-gluon interactions in the processes involving nuclear targets. One direction in such studies is to explore the onset of the quark gluon degrees of freedom in nuclear dynamics. The other direction is using the nuclear targets as a “micro-labs” in studies of the QCD processes involving protons and neutrons bound in the nucleus. In the proposed research, we work in both directions considering high energy photo- and electro-production reactions involving deuteron and 3 He nuclei.
In the first half of the research, we study the high energy break-up of the 3 He nucleus, caused by a incoming photon, into a proton-deuteron pair at the large center of mass scattering angle. The main motivation of the research is the theoretical interpretation of recent experimental data which revealed the unprecedentedly large exponent s −17 , for the energy dependence of the differential cross section. In the present research, we extend the theoretical formalism of the hard QCD rescattering model to calculate energy and angular dependences of the absolute cross section of the γ 3 He → pd reaction in high momentum transfer limit.
The second half of the research explores the deep-inelastic scattering of a polarized electron off the polarized deuteron and 3 He nuclei, to explore the quark-gluon structure of polarized neutron. The main reason of using deuteron is that it is the most simple and best understood nucleus. While the reason of using polarized 3 He as an effective polarized neutron target is that because of the Pauli-principle, the two protons in the target are in the opposite spin states and thus the neutron has all the polarization of the 3 He nucleus. However this approximation is exact only for the S-state and becomes less accurate with the increase of the internal momentum of the bound nucleons in the nucleus. There are several planned experiments which will be performed during next few years at the kinematics in which the internal momenta of the probed neutron cannot be neglected. Therefore, for the reliable interpretation of the data, all the nuclear effects, especially the effects related to the relativistic treatment of high momentum component of the nuclear wave function, should be taken into account. In this work, we developed a comprehensive theoretical framework for calculation of the all relevant nuclear effects that will allow the accurate extraction of the neutron data from deepinelastic scattering involving deuteron and 3 He targets.
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Chiotti, Tony. "A Few More Words to Part." PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2349.
Full textAbstract:
This is a collection of creative nonfiction writing. It includes an essay on capturing experience and perception, a piece of immersion journalism covering the inhabitants of a game store, and various examples of memoir.
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Zhang, Xiaoying. "Contrast improvement of few-cycle pulses." Thesis, Umeå universitet, Institutionen för fysik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-165565.
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The intense few-cycle laser pulses play an important role in the investigations of laser-plasma interaction. However, one of the biggest challenges in their generation is the reduction of temporal intensity contrast by introducing undesired pre-pulses and a long pedestal. Two techniques were investigated in this work to improve the contrast. First, the crossed-polarized wave (XPW) generation was optimized to get clean pulse. The conditions for XPW were optimized including crystal thickness and maximal background pressure in the vacuum cell. Second, the method of elliptical polarization rotation (EPR) in a gas-filled hollow-core fiber (HCF) was implemented to produce both broadened and cleaned pulse, since its setup is much simpler. For the tested EPR-based nonlinear filter, the spectral smoothening and broadening were obtained. The contrast of cleaned pulse was characterized providing 2 order of magnitude contrast enhancement, while it had a high average power of 80 mW. The EPR-based nonlinear filter is a promising simplified technique in the development of intense few-cycle lasers.
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Cherry, Donna J., and John G. Orme. "Finding the Vital Few Foster Mothers." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/7655.
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Background and Purpose: Many foster parents serve briefly, and foster and adopt few children. This makes it difficult to ensure the placement, care, stability, and well-being of foster children. Rather than focus on this majority of foster parents, it may be more useful to understand highly productive foster parents. The Pareto Principle provides a useful conceptual framework for doing this. This principle originates from economics and has empirical support in other fields. It also is known as the 80-20 rule or the Vital Few and states that roughly 80% of effects come from 20% of causes. This presentation will report research that identified such a group of foster parents and will describe their characteristics.
Methods: In Study 1 we used a cross-sectional design and a national non-probability sample of 304 non-kinship foster mothers. In Study 2 we used data from the National Survey of Current and Former Foster Parents (NSC&FFP), which included a national probability sample of 876 non-kinship foster families. We used latent class analysis (LCA) to identify discrete subgroups of foster families based on number of children fostered; years fostered; and number of foster children in home at the time of study participation. Study 1 also included number of foster children adopted and number removed at foster parents' request. In Study 1 we also examined differences between subgroups in the quality of care provided.
Results: LCA revealed two classes: 21% and 79% of the sample in Study 1, and 19% and 81% in Study 2. We refer to the smaller group as the Vital Few and the larger as the Useful Many. Vital Few: families fostered 73% and 74% of children in Study 1 and 2, respectively; 10 to 11 times more children than the Useful Many, despite having fostered only two to three times longer. Also, in both studies the Vital Few had 50% more foster children in their homes. Finally, the Vital Few in Study 1 had adopted twice as many children and requested removal rate was of one-half.
In Study 1 we regressed class membership on quality of care indicators using logistic regression. The odds of being in the Vital Few were higher for mothers who: were less likely to use psychological control in parenting or inconsistent parenting; had less need for social readjustment; had more time to foster; and anticipated more help with fostering from professionals. Mothers who anticipated more help with fostering from kin were less likely to be in the Vital Few.
Conclusions and ImplicationsFindings suggest that a disproportionately small percentage of foster parents care for most foster children. Understanding the characteristics of these resilient Vital Few can inform recruitment and retention efforts and the designation of other limited resources. Embracing the phenomenon of the Vital Few can reduce frustration of workers and provide more positive and realistic expectations of foster parents. Further research on the Vital Few is warranted to assess the motivations of this group, the quality of care provided, and outcomes of children fostered by these families.
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Che, Shi. "Quantum Transport in Few-layer Graphene." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1574864398913631.
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Söderberg, John. "FPS i en interaktiv 3D-modellvisare med WebGL : En FPS-jämförelse av WebGL Javascriptbiblioteken Three.js och Babylon.js." Thesis, Högskolan i Skövde, Institutionen för informationsteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-18642.
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Denna studie jämför skillnader i FPS mellan de två WebGL-biblioteken Three.js och Babylon.js. Prestandan som mäts är hur många bilder per sekund, eller FPS (engelska frames per second) som en webbapplikation med 3D-grafik klarar att rendera. Prestandamätningarna utförs på en 3D-modellvisare som implementeras i både Three.js och Babylon.js. Testerna utförs på en bärbar dator med Windows 10. Hypotesen antar att Three.js inte kommer att prestera bättre än Bablyon.js Resultatet från studien visar dock att Three.js presterar bättre än Babylon.js. Studiens syfte är att ge utvecklare en uppfattning om vilket WebGL-bibliotek som är mest lämpligt att använda vid exempelvis utveckling av en e-handelssida där produkter har 3D-förhandsvisningar. Studien kan användas som grund eller inspiration för framtida forskning inom samma område.
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Dardouri, Fawzia. "Dispositif d’assistance associé à des robots manipulateurs utilisés dans des procédés de fabrication/FSW." Thesis, Paris, ENSAM, 2018. http://www.theses.fr/2018ENAM0036/document.
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Les robots industriels sont très utilisés aujourd’hui dans de nombreuses applications industrielles pour leur polyvalence et leur facilité programmation. Cependant, malgré leurs performances, ces robots ne sont pas adaptés à certains procédés de fabrication où des forces uniformes et élevées ainsi qu'une précision de positionnement appropriée sont requises. Le présent travail est axé sur la robotisation de l'une des opérations à forte charge, le soudage par friction-malaxage (FSW). Cette méthode d’assemblage s’utilise pour assembler des pièces en phase solide. Pour cette raison, une force de poussée très élevée est nécessaire pour ramollir le matériau pendant cette opération. En raison des forces élevées, la position de l'outil dévie de la trajectoire désirée. Dans ces travaux de thèse, la possibilité d'utiliser un dispositif d’assistance associé à un robot manipulateur est étudiée afin d’améliorer sa capacité de charge et sa rigidité. Dans une première partie, une modélisation géométrique, cinématique et dynamique ainsi que de déformation d’un robot industriel Kuka KR500-2MT est développée en localisant la flexibilité au niveau des articulations. La deuxième partie consiste à améliorer les performances de la robotisation du procédé FSW par différentes méthodes qui sont la modification du système de compensation de gravité, l’ajout d’une masse additionnelle sur l’outil, l’ajout d’une structure parallèle et l’utilisation de deux robots en mode coopératif. Les deux dernières solutions consistent à exercer des forces directement sur l’outillage. De cette façon, le mouvement de l'outil est principalement piloté par le robot industriel, tandis que le dispositif d’assistance (soit la structure parallèle ou le deuxième robot utilisé dans le système coopératif) assure la génération de forces de poussées très élevées. Des algorithmes d’optimisation ont été utilisés afin de minimiser les déviations de l’outil et donc réduire les défauts de soudage. Finalement, une étude de l’espace de travail est menée en utilisant le logiciel Catia. La connaissance de l'espace de travail pour les solutions proposées nous permet d’estimer les applications de soudage possibles ainsi que leur comparaisonNowadays industrial robots are used in many manufacturing applications because of their versatility and easy applicability. Notwithstanding their performance these robots are not suitable for some manufacturing processes where uniform and high forces together with suitable precision of position are required. The present research is focused on the robotization of one of the high-thrust operations, the friction stir welding (FSW). This method for connecting two parts works while the connected materials are in the solid phase. For this reason a very high axial force is needed to soften the material during the welding process. Due to these high forces the position of the tool of a serial robot deviates from the desired trajectory. In this PhD work, the possibility of using a parallel structure device is investigated to improve the load capacity and stiffness of a heavy loadmanipulator robot. In a first part, the geometric, kinematic and dynamic modeling and the flexibility of an industrial robot, Kuka KR500-2MT are developed by locating flexibility at the joints. The second part is to improve the performance of the FSW process using an industrial robot. So different methods are examined: the modification of the gravity compensation system, the addition of an additional mass on the tool, the addition of a parallel structure and the use of a cooperative system. The last two solutions exert forces directly on the process tool. In this way the movement of the tool is mainly generated by the industrial serial robot, while the assistive device (either the parallel structure or the second robot used in the cooperatif system) ensures the generation of very high axial forces. Optimization algorithms are developed to minimize deviations and thus reduce welding defects. Finally, a study of the workspace is studied using Catia software. Knowledge of the system workspace with the proposed solutions allows to estimate the possible welding applications that can be achieved using these systems
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Kriborg, Frida. "Resning i skattemål : - En studie av resningsbestämmelserna i regeringsformen och förvaltningsprocesslagen." Thesis, Karlstads universitet, Handelshögskolan, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-38783.
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Lourdin, Morgane. "Etudes biochimiques et structurales de la réparation des lésions multiples de l'ADN." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENV007/document.
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Pham, Hong Phong. "Studies on Optimal Colorful Structures in Vertex-Colored Graphs." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS528.
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Dans cette thèse, nous étudions des problèmes différents de coloration maximale dans les graphes sommet-colorés. Nous nous concentrons sur la recherche des structures avec le nombre maximal possible de couleurs par des algorithmes en temps polynomial, nous donnons aussi la preuve des problèmes NP-difficiles pour des graphes spécifiques. En particulier, nous étudions d’abord le problème de l’appariement coloré maximum. Nous montrons que ce problème peut être résolu efficacement en temps polynomial. En plus, nous considérons également une version spécifique de ce problème, à savoir l’appariement tropical, qui consiste à trouver un appariement contenant toutes les couleurs du graphe original. De même, un algorithme de temps polynomial est également fourni pour le problème de l’appariement tropical avec la cardinalité minimale et le problème de l’appariement tropical maximum avec la cardinalité minimale. Ensuite, nous étudions le problème des chemins colorés maximum. Il existe deux versions pour ce problème: le problème de plus court chemin tropical, c’est-à-dire de trouver un chemin tropical avec le poids total minimum et le problème de plus longue chemin coloré, à savoir, trouver un chemin avec un nombre maximum possible de couleurs. Nous montrons que les deux versions de ce problème sont NP-difficile pour un graphe orienté acyclique, graphes de cactus et graphes d'intervalles où le problème de plus long chemin est facile. De plus, nous fournissons également un algorithme de paramètre fixe pour le premier dans les graphes généraux et plusieurs algorithmes de temps polynomiaux pour le second dans les graphes spécifiques, y compris les graphes des chaîne bipartites, graphes de seuil, arborescences, graphes des blocs et graphes d'intervalles appropriés. Ensuite, nous considérons le problème des cycles colorés maximum. Nous montrons d'abord que le problème est NP-difficile même pour des graphes simples tels que des graphes divisés, des graphes bi-connecteurs et des graphes d'intervalles. Nous fournissons ensuite des algorithmes de temps polynomial pour les classes de graphes de seuil et graphes des chaîne bipartites et graphes d'intervalles appropriés. Plus tard, nous étudions le problème des cliques colorées maximum. Nous montrons tout d’abord que le problème est NP-difficile même pour plusieurs cas où le problème de clique maximum est facile, comme des graphes complémentaires des graphes de permutation bipartite, des graphes complémentaires de graphes convexes bipartites et des graphes de disques unitaires, et aussi pour des graphes sommet-colorées appropriés. Ensuite, nous proposons un algorithme paramétré XP et des algorithmes de temps polynomial pour les classes de graphes complémentaires de graphes en chaîne bipartites, des graphes multipartites complets et des graphes complémentaires de graphes cycles. Enfin, nous nous concentrons sur le problème des stables (ensembles indépendants) colorés maximum. Nous montrons d’abord que le problème est NP-difficile même dans certains cas où le problème de stable maximum est facile, tels que les co-graphes et les graphes des P₅-gratuit. Ensuite, nous fournissons des algorithmes de temps polynomial pour les graphes de grappes, et les arbresIn this thesis, we study different maximum colorful problems in vertex-colored graphs. We focus on finding structures with the possible maximum number of colors by efficient polynomial-time algorithms, or prove these problems as NP-hard for specific graphs. In particular, we first study the maximum colorful matching problem. We show that this problem can be efficiently solved in polynomial time. Moreover, we also consider a specific version of this problem, namely tropical matching, that is to find a matching containing all colors of the original graph, if any. Similarly, a polynomial time algorithm is also provided for the problem of tropical matching with the minimum cardinality and the problem of maximal tropical matching with the minimum cardinality. Then, we study the maximum colorful paths problem. There are two versions for this problem: the shortest tropical path problem, i.e., finding a tropical path with the minimum total weight, and the maximum colorful path problem, i.e., finding a path with the maximum number of colors possible. We show that both versions of this problem are NP-hard for directed acyclic graphs, cactus graphs and interval graphs where the longest path problem is easy. Moreover, we also provide a fixed parameter algorithm for the former in general graphs and several polynomial time algorithms for the latter in specific graphs, including bipartite chain graphs, threshold graphs, trees, block graphs, and proper interval graphs. Next we consider the maximum colorful cycles problem. We first show that the problem is NP-hard even for simple graphs such as split graphs, biconnected graphs, interval graphs. Then we provide polynomial-time algorithms for classes of threshold graphs and bipartite chain graphs and proper interval graphs. Later, we study the maximum colorful cliques problem. We first show that the problem is NP-hard even for several cases where the maximum clique problem is easy, such as complement graphs of bipartite permutation graphs, complement graphs of bipartite convex graphs, and unit disk graphs, and also for properly vertex-colored graphs. Next, we propose a XP parameterized algorithm and polynomial-time algorithms for classes of complement graphs of bipartite chain graphs, complete multipartite graphs and complement graphs of cycle graphs. Finally, we focus on the maximum colorful independent set problem. We first prove that the problem is NP-hard even for some cases where the maximum independent set problem is easy, such as cographs and P₅-free graphs. Next, we provide polynomial time algorithms for cluster graphs and trees
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Andreasson, Mikael. "Förflyttad till en annan värld : en litteraturstudie om immersion och användargränssnitt i digitala spel." Thesis, Högskolan Kristianstad, Sektionen för hälsa och samhälle, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-11458.
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Jag har med denna litteraturstudie närmare undersökt begreppet immersion och dess koppling tillgränssnitt i digitala spel inom FPS-genren (First-Person Shooter). I studien presenteras först tidigare forskning som skett inom områdena för immersion, användargränssnitt samt digitala spel. Utifrån detta lyfts det sedan upp tre saker i problemformuleringen: att immersion kan påverka människor, att gränssnitt är en viktig länk mellan spelet och spelaren samt att genren även har en betydelse vid utformandet av gränssnitt. Syftet med studien har varit att undersöka aktuell teori vilket har ökat min förståelse för immersion, användargränssnitt samt digitala spel. En kvalitativ inriktad forskning med hermeneutiken som metod har använts vid utförandet avstudien. Jag presenterar i resultatkapitlet exempel på tre stycken spel i FPS-genren där det framkommer att två av dessa spelen har gränssnitt som stödjer immersion varav det tredje spelet har ett gränssnitt som bryter immersionen. Från resultatet har sedan fyra stycken riktlinjer extraherats med syftet att ge gränssnittsdesigners tydliga instruktioner om vad som gäller vid utvecklingen av gränssnitt som stödjer immersion i FPS-genren. Slutsatsen har med studien blivit att gränssnitt kan påverka immersion i både en positiv och negativ mening.I have with this literature study closer studied the term immersion and it's connection to user interfaces within video games in the FPS-genre (First-Person Shooter). The study first presents previous research that has occurred in the fields of immersion, user interfaces and video games. Three things are then, from this, later lifted up in the problem specification, those three are, that immersion can affect people, that user interfaces are critical links between the gamer and the game and that the genre is significant in the development of a user interface. The purpose of the study has been to a research current theory which has expanded my knowledge in the fields of immersion, user interfaces and video games. A qualitative oriented research with hermeneutics as the methodology has been applied in the execution of the study. I then present, in the results chapter, three examples of games in the FPS-genre where it is found that two of these games have a user interface that supports immersion with the third game having a user interface that breaks immersion. The results have then been extracted into four guidelines with the purpose to give user interface designers clear instructions about what applies in the development of user interfaces that supports immersion in the FPS-genre. The conclusion of the study has then been that user interfaces can affect immersion in both a positive and in a negative way.
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Johansson, Ida, and Andreas Goldmann. ""Verkligheten anropar!" : En kvalitativ studie om upplevelsen av flow och immersion för användare av Mutiplayer FPS-spel." Thesis, Linnéuniversitetet, Institutionen för informatik (IK), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-104818.
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Användarupplevelse anses vara en viktig aspekt inom dagens spel och utgör en betydande roll för framgång inom branschen. Flertal funktioner bör beaktas vid utvecklingen av optimal upplevelse och eftersom spelindustrin ständigt utvecklas måste även människans kunskap om komponenterna som skapar den optimala upplevelsen utvecklas. För avhandlingen undersöks flow och immersion som komponenter av optimal upplevelse i syfte att skapa förståelse för aktiviteters potential att inducera optimala spelupplevelser inom FPS-spel. Samtidigt undersöks möjligheten att kombinera flow och immersion inom en teori, för att uppnå bättre förståelse för deras relation till varandra inom en spelmiljö. Teorin som presenteras är flow theory, vilken staterar att specifika sinnestillstånd kan observeras när användare utför uppgifter som hen har olika kompetensnivåer inom och som motsätter sig olika utmaningsnivåer. Upplevelsen av flow faller inom de sinnestillstånd som kan observeras, medan immersion ej observeras. Dock överlappar immersion och flow inom flertal av de aspekter som möjliggör flows plats inom teorin, således finns möjlighet för immersion att potentiellt identifieras inom den. För att undersöka detta används både kvantitativa och kvalitativa metoder i form av enkätundersökningar och intervjuer med spelare av FPS-spel. Resultaten visar att ingen specifik aktivitet inom dessa spel kan identifieras med högre nivåer av vare sig flow eller immersion och ingen ytterligare forskning inom ämnet genomfördes. Resultaten påvisade att potentiell immersion kan uppstå inom flertal sinnestillstånd inom flowteorin, dock varierade nivåerna av potentiell immersion mellan dem. Vänners närvaro ökar potentialen att uppleva immersion.User experience is an important aspect of modern gameplay and plays an important role throughout the various parts that gaming has to offer. There are many features to regard in the development of the optimal gaming experience and as the industry continues to advance, our knowledge about the components of the optimal experience must advance with it. In this thesis flow and immersion as components of optimal user experience will be researched to gain an understanding for which activities within FPS-games show the most potential to induce these optimal gaming experiences. Whilst also attempting to combine them under one theory to achieve a better understanding of their relation to one another in a game setting. The theory presented is flow theory, which states that specific states of mind can be observed when users perform tasks in which they possess varying levels of competence and that oppose varying levels of challenge. The experience of flow is an observable state of mind within the theory, whilst immersion is not. However, immersion overlaps with multiple aspects of the flow experience that enables it to be part of this theory, thus enabling immersion's potential to be identified within it. To investigate this both quantitative and qualitative methods are used, consisting of surveys and interviews with gamers of FPS-style games. The results show that no specific activity within these games can be identified with higher levels of neither flow nor immersion and no further research on the subject was conducted. The results regarding immersion within the flow theory gave positive results. The potential to experience immersion was observed within multiple parts of the theory, even though the levels of potential immersion varied between the different areas. The results also showed that the presence of friends increased the potential to experience immersion.
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Dimitroglou, Rizell Georgios. "Knotted Legendrian surfaces with few Reeb chords." Licentiate thesis, Uppsala universitet, Algebra, geometri och logik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-139417.
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Hornæs, Daniel. "Low-Cost FPU : Specification, Implementation and Verification." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elektronikk og telekommunikasjon, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11145.
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This report aims to provide a complete specification of an IEEE-754 1985 compliantdesign, as well as a working, synthesizable implementation in Verilog HDL. Thereport is based on a preliminary project, which analyzed the IEEE-754 standardand suggested a set of algorithms suitable for a compact realization.Through traditional methods of both algorithmic analysis and dataanalysis,requirements of functional units are derived, and operations are scheduled.A set of functional simulations assert the correctness of the design, while areaand performance analysis provides information on the speedup gained, versus thehardware cost.Finally, the results obtained are compared to existing implementations, bothhardware and software.
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Ališauskas, Skirmantas. "Infrared Few-Cycle Pulse Optical Parametric Amplifier." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20101001_145118-06284.
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Main objective of this thesis is to generate and amplify few cycle pulses in the infrared region. In this thesis, two approaches were introduced for few cycle pulse parametric amplification at 800 nm and 1.5 μm. First approach is dedicated for prospects for increasing average power of OPCPA via multi-beam pumping; the second approach is dedicated for generation of carrier-envelope-phase (CEP) stable high energy (up to tens of millijoules) few-cycle pulses at 1.5 μm.
An experimental investigation of two or three beams-pumped OPCPA system based on type I BBO crystal is presented. The 2nd OPA stage was pumped by two or three pump beams derived from independent Nd:YAG laser amplifiers. The efficiency of interaction was shown to be comparable to that of single-beam pumped OPA and diminishes only slightly due to cascaded parametric diffraction of interacting waves. The effect was observed and its impact on efficiency of parametric amplification process was shown to decrease at larger intersecting angles of pump. In the prospect, the use of multiple lasers for OPA pumping has an appeal for increasing the repetition rate and consequently the average power of an ultrashort pulse laser system. Finally, the concept and realization of hybrid system based on type II KTP OPCPA and filamentation are described. A CEP-stable 1.5 μm OPCPA system with pulse energies up to 12.5 mJ after 4 OPA stages is demonstrated. Furthermore, self-compression of CEP-stable 2.2 mJ, 74.4 fs, 1.57 μm input... [to full text]Disertacijos darbo tikslas – suformuoti ir parametriškai stiprinti kelių optinių ciklų trukmės impulsus infraraudonojoje srityje Šioje disertacijoje buvo tirtos dvi moduliuotosios fazės („čirpuotų“) impulsų parametrinio stiprinimo sistemos, stiprinančios ypač plataus spektro impulsus 800 nm bei 1,5 μm srityse. Pirmoji sistema skirta tirti galimybę didinti lazerinės spinduliuotės vidutinę galią keliais pluoštais kaupinamame parametriniame stiprintuve; antroji sistema skirta kelių optinių ciklų trukmės stabilios fazės impulsų formavimui 1,5 μm srityje. Disertacijoje aprašomas I tipo parametrinis stiprintuvas, kurio 2-oji pakopa buvo kaupinama dviem arba trimis nepriklausomų lazerinių šaltinių pluoštais. Nustatyta, kad parametrinį stiprintuvą kaupinant keliais pluoštais stebimas naujų erdvinių komponentų atsiradimas, kuriuos sąlygoja parametrinė pakopinė difrakcija, o tai mažina bendrą sistemos energetinio keitimo efektyvumą.. Darbo metu pademonstruota galimybė mažinti parametrinės difrakcijos sąlygotus nuostolius parametriniame stiprintuve derinant kampus tarp kaupinimo pluoštų. Taip pat pristatomas alternatyvus būdas formuoti didelės energijos (kelių dešimčių milidžaulių) kelių optinių ciklų trukmės stabilios fazės impulsus 1,5 μm srityje. Būdas paremtas sąlyginai siauro spektro 1,5 μm srityje stiprinimu II tipo KTP kristale bei spektro plėtra inertinėse dujose po stiprinimo. 4 pakopų parametriniame stiprintuve pasiekta iki šiol didžiausia 12,5 mJ impulso energija 1,5 μm... [toliau žr. visą tekstą]
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Hakimi, Shirin. "Exact Diagonalization of Few-electron Quantum Dots." Thesis, Linnaeus University, School of Computer Science, Physics and Mathematics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-2550.
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We consider a system of few electrons trapped in a two-dimensional circularquantum dot with harmonic confinement and in the presence of ahomogeneous magnetic field, with focus on the role of e-e interaction. Byperforming the exact diagonalization of the Hamiltonian in second quantization,the low-lying energy levels for spin polarized system are obtained. The singlet-triplet oscillation in the ground state of the two-electron system showing up inthe result is explained due to the role of Coulomb interaction. The splitting ofthe lowest Landau level is another effect of the e-e interaction, which is alsoobserved in the results.
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Schellingerhout, Nicolaas Willem. "Factorizability in the numerical few-body problem." [S.l] : [Groningen] : [s.n.] ; [University Library Groningen] [Host], 1995. http://irs.ub.rug.nl/ppn/141192240.
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Tarbutt, Michael Roy. "Spectroscopy of few-electron highly charged ions." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365339.
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Chipperfield, Luke Edward. "High harmonic generation with few-cycle pulses." Thesis, Imperial College London, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487550.
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This thesis studies the response of atoms and molecules to intense few-cycle laser pulses. It is the extremely high frequency dipole radiation generated from such a response that is of interest, both for its exploitation towards generating isolated attosecond pulses and because of the information such radiation contains concerning the laser pulse and electronic wavefunction responsible for its generation. Using a variety of models the process of high order harmonic generation in single atoms is studied in detail to reveal its underlying structure. The high harmonic spectrum is formed from bursts of radiation released every half-cycle of the laser field. The sensitivity of this half-cycle radiation to the precise waveform of the laser field is investigated. In particular the implications of these sensitivities to the stability of attosecond pulse production is studied. The work on single atom high harmonic generation is utilised towards investigations into the high harmonic generation from a volume of atoms. Propagation of the fields through such a volume greatly affects the final spectrum due to phase-matching. A new phenomenon is presented due to this phase-matching which leads tdthe manifestation of half-cycle cut-offs in the propagated spectra. A powerful new technique for measuring few-cycle pulse properties, utilising these half-cycle cut-offs, is developed and demonstrated. It is found capable of measuring the absolute carrier-envelope phase of the driving laser field to within 50 mrad, the highest accuracy of such a measurement achieved to date. The use of spatio-spectral filtering for isolating a half-cycle cut-off is proposed as a method for generating wavelength tunable attosecond pulses. Finally, work is carried out towards the development of a strong field approximation model capable of simulating high harmonic generation from molecules. Such a model is found to be suitable for such calculations and an interesting interference regime is commented on.