Дисертації з теми "Home composts"
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1
Kohli, Alice. "Effets de composts autoproduits et d'un biochar sur le transfert d'éléments trace dans des légumes de jardins familiaux modérément contaminés." Thesis, Rennes, Agrocampus Ouest, 2022. http://www.theses.fr/2022NSARD098.
Анотація:
Les jardins familiaux ont souvent été installés sur des sols urbains sans évaluation préalable du risque sanitaire. Le diagnostic de contamination du sol par des éléments trace comme le plomb (Pb) peut compromettre la poursuite du jardinage. Pour éviter un changement d’usage, l’apport au sol de compost industriel peut être efficace mais le potentiel des composts autoproduits par les jardiniers eux-mêmes doit être évalué. Ce travail de thèse a eu pour premier objectif d’analyser les pratiques de compostage dans les jardins familiaux et sélectionner des composts autoproduits différents en termes de propriétés biochimiques et de contenu en éléments trace. Les pratiques de compostage et la qualité des composts sont très variables. Les composts autoproduits au jardin (domestiques)sont généralement pauvres en matière organique et parfois contaminéscontrairement aux composts autoproduits en pied d’immeuble ou en restauration (collectifs) également utilisés au jardin. Le second objectif a été d’évaluer le risque sanitaire potentiel lié à la consommation de légumes de jardins familiaux modérément contaminés en Pb (100-200 mg.kg-1) amendés avec des composts autoproduits. Pour tenter d’améliorer la remédiation, du biochar a aussi été introduit. Une alimentation composée essentiellement des légumes autoproduits au jardin ne présenterait pas de risque sanitaire mais l’apport de composts autoproduits à une dose élevée (10-20 kg.m-2) a pu augmenter la biodisponibilité de As dans des sols de jardins familiaux. L’apport combiné d’un compost autoproduit et d’un biochar a toutefois limité les transferts de As et de Pb tout en augmentant la biomasse des légumes autoproduitsFor some time, allotment gardens have often been established on urban soils without prior health risk assessment. Soil analysis revealing contamination by trace elements such as lead (Pb) may now compromise the practice of gardening. To prevent a restriction or change of soil use, the introduction of industrial compost to the soil can be efficient, but the potential of composts self-produced by the gardeners themselves must be evaluated. The first objective of this thesis was to analyze composting practices in allotment gardens and select self-produced composts with different biochemical properties and trace element content. The composting practices and the quality of these composts are very variable. Composts self-produced in the garden (home composts) are generally poor in organic matter and sometimes contaminated,contrary to composts self-produced at the foot of buildings or in restoration (community composts) also used in gardens. The second objective was to assess the potential health risk of consuming vegetables from allotment gardens moderately contaminated with Pb (100 - 200 mg.kg-1) amended with self-produced composts. In an attempt to improve remediation, biochar was also introduced into the soil. A diet composed essentially of self-produced vegetables in the garden would not present a health risk, but the addition of self-produced composts at a high dose (10-20 kg.m-2) could increase the bioavailability of As in allotment garden soils. In contrast, the combined addition of self-produced compost and biochar limited the transfer of both As and Pb while simultaneously increasing the biomass of self-produced vegetables
2
EL, AMOURI HANZ. "Synthese et reactivite catalytique de composes homo- et heterobinucleaires." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13156.
Анотація:
Utilisation du ligand tripode ch(pph::(2))::(3) pour synthetiser des complexes mononucleaires (rh(i), ir(i) et mo(0)), homobinucleaires (rh(i)-rh(i)), heterobinuclaires (rh(i)-cu(i), rh(i)-au(i), ir(i)-au(i) et polynucleaires (rh(i)::(4), rh(i)-cu(i)::(2)). Etude des proprietes catalytiques en hydrogenation des olefines et acetylene
3
Luchian, Cosmina Ioana. "Applicazione della tecnica "incremental hole drilling" su materiali compositi." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/11588/.
Анотація:
Durante la vita operativa di un aeromobile, gli elementi costitutivi possono essere soggetti a diverse tipologie di carichi. Questi carichi possono provocare la nascita e la propagazione di eventuali cricche, le quali una volta raggiunta una determinata dimensione possono portare alla rottura del componente stesso causando gravi incidenti.
A tale proposito, la fatica costituisce uno dei fattori principali di rottura delle strutture aeronautiche.
Lo studio e l’applicazione dei principi di fatica sugli aeroplani sono relativamente recenti, in quanto inizialmente gli aerei erano realizzati in tela e legno, un materiale che non soffre di fatica e assorbe le vibrazioni.
I materiali aeronautici si sono evoluti nel tempo fino ad arrivare all’impiego dei materiali compositi per la costruzione degli aeromobili, nel 21. secolo.
Il legame tra nascita/propagazione delle cricche e le tensioni residue ha portato allo sviluppo di numerose tecniche per la misurazione di queste ultime, con il fine di contrastare il fenomeno di rottura a fatica.
Per la misurazione delle tensioni residue nei componenti metallici esistono diverse normative di riferimento, al contrario, per i materiali compositi, la normativa di riferimento è tuttora oggetto di studio.
Lo scopo di questa tesi è quello di realizzare una ricerca e studiare dei metodi di riferimento per la misurazione delle tensioni residue nei laminati compositi, tramite l’approfondimento di una tecnica di misurazione delle tensioni residue, denominata Incremental Hole Drilling.
4
Balme, Lionel. "Interfaces homme-machine plastiques : une approche par composants dynamiques." Phd thesis, Université Joseph Fourier (Grenoble), 2008. http://tel.archives-ouvertes.fr/tel-00432115.
Анотація:
Cette thèse s'inscrit dans le domaine de l'interaction homme-machine (IHM) et s'intéresse à l'adaptation dynamique des systèmes interactifs dans le cadre de l'informatique ubiquitaire. Dans ce cadre, les interfaces utilisateurs doivent devenir plastiques, c'est-à-dire être capables de s'adapter ou d'être adaptées au contexte de l'interaction tout en préservant leur utilisabilité. L'objectif de cette thèse est de comprendre la problématique de la plasticité des IHM à l'exécution et de la traiter sous l'angle du génie logiciel. L'étude de cette problématique montre qu'un système interactif plastique est un logiciel réparti, reconfigurable dynamiquement et constitué d'entités logicielles hétérogènes. Or, aucune proposition de l'état de l'art des systèmes interactifs plastiques ne couvre totalement l'espace problème de la plasticité à l'exécution. De même, aucune solution du génie logiciel pour la construction de logiciels répartis reconfigurables dynamiquement ne prend en compte les spécificités des IHM plastiques. Cette thèse propose une décomposition logicielle de référence qui identifie l'ensemble des fonctions nécessaires à la plasticité des systèmes interactifs, ainsi qu'Ethylene, un modèle à composants dynamiques issu d'une combinaison des approches à composants et à services. Ethylene est conçu pour répondre aux spécificités de l'IHM, et permet de constituer dynamiquement des assemblages reconfigurables de composants IHM de nature hétérogène. Enfin, un langage XML et un cadre de développement incarnent le modèle Ethylene sur un plan technique.
5
Phan, Anh cang. "Crack removal and hole filling on composite subdivision meshes." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4068/document.
Анотація:
Construire une surface lisse d'un objet 3D est un problème important dans de nombreuses applications graphiques. En particulier, les méthodes de subdivision permettent de passer facilement d'un maillage discret à une surface continue. Un problème général résultant de la subdivision de deux maillages initialement connectés le long d'un bord est l'apparition de fissures ou de trous entre eux. Ces fissures produisent non seulement des formes indésirables, mais induisent aussi des difficultés pour les traitements ultérieurs. Il faut donc réparer ces défauts de sorte que la surface obtenue soit lisse et puisse être subdivisée ou modifiée. Nous proposons de nouvelles méthodes pour relier deux maillages avec des résolutions différentes en utilisant une transformée en ondelettes B-splines et une approximation locale ou une interpolation locale à l'aide de fonctions de base radiales (RBF). Ces procédés génèrent un maillage de connexion où la continuité est contrôlée. La résolution du maillage est ajustable pour respecter le changement de résolution entre les zones grossières et fines. En outre, nous présentons des méthodes pour combler les trous à n-côtés, et le raffinement des maillages grâce à un schéma de subdivision adaptative. Nous avons conçu, implémenté et testé les algorithmes en MatLab pour illustrer nos méthodes et montrer des résultats expérimentaux. Ces algorithmes sont mis en oeuvre sur de nombreux modèles d'objets 3D avec des formes complexes. En outre, nous avons fourni des approches différentes pour chaque problème. Ainsi, les résultats des différentes approches sont comparés et évalués afin d'exploiter les avantages et les inconvénients de ces approchesConstructing a smooth surface of a 3D object is an important problem in many graphical applications. In particular, subdivision methods permit to pass easily from a discrete mesh to a continuous surface. A generic problem arising from subdividing two meshes initially connected along a common boundary is the occurrence of cracks or holes between them. These cracks not only produce undesired shapes, but also bring serious trouble for further mesh processing. They must be removed or filled so that the produced surface is smooth and can be further subdivided or edited. In order to remove cracks, we propose new methods for joining two meshes with different resolutions using a Lifted B-spline wavelet transform and a local approximation or radial basis function (RBF) local interpolation. These methods generate a connecting mesh where continuity is controlled from one boundary to the other and the connecting mesh can change gradually in resolution between coarse and fine areas. Additionally, we introduce methods for filling n-sided holes, and refining meshes with an adaptive subdivision scheme. We have designed, implemented, and tested the algorithms in MatLab to illustrate our proposed methods and show experimental results. These algorithms are implemented on many 3D object models with complex shapes. Additionally, we have provided some different approaches for each problem. Thus, results from the different approaches are compared and evaluated to exploit the advantages and disadvantages of these approaches
6
Amouri, Hani El. "Synthèse et réactivité catalytique de composés homo et hétérobinucléaires." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37602308f.
7
Gil, Marcelo Priebe. "Homo e copolimerização do etileno utilizando compostos de ti(iv) contendo ligantes trispirazolilborato." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1999. http://hdl.handle.net/10183/21612.
Анотація:
Os compostos não metalocênicos do tipo {TpMs*}TiCh (3) e {TpMS}TiCh (4) foram utilizados em reações de polimerização de etileno na presença de MAO ou TIBA/MAO, objetivando verificar a influência do cocatalisador, da temperatura e do solvente sobre a produtividade e as propriedades dos polímeros, bem como a influência da variação da razão Al/Ti sobre a produtividade. Levando em consideração a produtividade, o melhor sistema de polimerização encontrado envolve uso do TIBA/MAO em reação feita em hexano a 60°C. As curvas de DSC indicam a formação de polímeros altamente cristalinos e Tm na faixa de 128 a 138°C. As análises de GPC indicam que o peso molecular dos polímeros decrescem com o aumento da temperatura de polimerização. O precursor catalítico {TpMS*} TiCh (3) polimeriza etileno a uma razão Al/Ti igual a 100 com excelente produtividade. Os precursores catalíticos 3 e 4 também foram utilizado nas reações de copolimerização de etileno/l-hexeno usando MAO como cocatalisador. Considerando os resultados de produtividade, os sistemas 3/MAO e 4/MAO mostraram uma diminuição da produtividade a medida que a concentração de 1-hexeno foi aumentada, determinando um efeito negativo do comonômero. Os dados de infravermelho bem como aqueles provenientes das curvas de DSC indicam que a porcentagem de l-hexeno incorporado no copolímero e a T m dependem das propriedades eletrônicas e estéricas do ligante Tp e da concentração de 1-hexeno utilizada. O aumento da concentração de 1-hexeno proporcionou um aumento de incorporação do comonômero no copolímero. A maior incorporação de 1-hexeno no copolímero foi encontrada para o sistema 3/MAO.The non-metallocene compounds such as {TpMS*}TiCb (3) and {TpMS}TiCb (4) have been used in the ethylene polymerization in the presence of MAO or TIBA/MAO, in order to verify the influence of the cocatalyst, Al/Ti ratio, temperature, and solvent on the productivity and on polymers properties. Taking account the productivity, the best polymerization system has been found using TIBA/MAO as cocatalyst in hexane at 60°C. The DSC curves have shown the formation of highly crystalline polymers and Tm ranging from 128 to 138°C. The GPC results have shown that the molecular weight of the polymers decreased when the polymerization temperature was increased. The catalyst precursor {TpMS*} TiCb (3) has shown excellent productivity using a lower Al/Ti ratio (AI/Ti = 100). The catalyst precursors 3 and 4 have also been used in the. ethylene/l-hexene copolymerization using MAO as cocatalyst. Taking into account the productivity results, the 1/MAO and 2lMAO systems have shown a decrease in the productivity when the l-hexene concentration in the feed was increased, determining a negative comonomer effect. The IR data as well as DSC results indicated that the l-hexene content in the copolymers and the melting point of these ones (Tm) depend on the electronic and steric properties of the Tp ligand and of the concentration of the comonomer in the feed. As the l-hexene concentration in the feed was increased, the incorporation of the comonomer increased as well. The higher l-hexene incorporation in the copolymer was found for 3/MAO.
8
Jansen, Zero. "What We Know: Queer Displacement and Reimagining Notions of Home." Ohio University Honors Tutorial College / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ouhonors1556115428029259.
9
Coelho, Reginaldo Teixeira. "The machinability of aluminium-based SiC reinforced metal matrix composite (MMC) alloy with emphasis on hole production." Thesis, University of Birmingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340966.
10
Burdet, Fabien. "Porphyrine-corroles homo- et hétérobimétalliques : leur intérêt dans la réduction du dioxygène en eau." Dijon, 2004. http://www.theses.fr/2004DIJOS056.
11
Garza, Rodriguez Carlos. "Deep-hole drilling measurements of residual and assembly stress in composite materials." Thesis, University of Bristol, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.720824.
12
Chastain, Patrick Alan. "Effects of load proportioning on the capacity of multiple-hole composite joints." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/90922.
Анотація:
This study addresses the issue of adjusting the proportion of load transmitted by each hole in a multiplehole joint so that the joint capacity is a maximum. Specifically two-hole-in-series joints are examined. The results indicate that when each hole reacts 50% of the total load, the joint capacity is not a maximum. One hole generally is understressed at joint failure. The algorithm developed to determine the load proportion at each hole which results in maximum capacity is discussed. The algorithm includes two-dimensional finite-element stress analysis and a failure criteria. The algorithm is used to study the effects of joint width, hole spacing, and hole to joint-end distance on load proportioning and capacity. To study hole size effects, two hole diameters are considered. Three laminates are considered: a quasi-isotropic laminate; a cross-ply laminate; and a 45 degree angle-ply laminate. By proportioning the load, capacity can be increased generally from 5 to 10%. In some cases a greater increase is possible.M.S.
13
Boeman, Raymond G. "Interlaminar deformations on the cylindrical surface of a hole in laminated composites : an experimental study /." Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-09162005-115037/.
14
Blanchard, Sébastien. "Vers la photosynthèse artificielle : synthèses et caractérisations de complexes homo-et hétéronucléaires manganèse et ruthénium-manganèse, étude du stockage d'équivalents oxydants." Paris 11, 2002. http://www.theses.fr/2002PA112188.
Анотація:
La photosynthèse est le processus de conversion de l'énergie solaire en énergie chimique. Ce manuscrit présente, après un bilan des connaissances sur la photosynthèse au chapitre I, les travaux réalisés en vue de l'obtention de complexes Ruthénium-Manganèse, modèles du transfert électronique au sein du photosystème II. Une première approche, décrite au chapitre II, a conduit à la formation d'un mélange de deux complexes. Bien que ceux-ci n'aient pu être séparés, une étude par diverses techniques spectroscopiques a permis leur identification : il s'agit de triades RuMn2 et Ru2Mn. Dans le chapitre III, deux nouvelles approches pour la synthèse d'un ligand [(Bipy)2Ru(PyN3)-BpmpH]+, susceptible de coordiner deux ions Manganèse, sont développées. Dans la première, la protection de la fonction phénolique du ligand NH2BpmpH par la formation d'un complexe dinucléaire de Zinc permet le couplage de l'amine avec un chlorure d'acide. Dans la seconde, la fonction phénolique n'est introduite, via une oxydation aromatique, qu'après couplage du ligand NH2Ar(DPA)2 avec un chlorure d'acide porté par le complexe de Ruthénium. Au cours de ces synthèses, une famille de ligand RBpmpH, ne différant que par les propriétés électroniques des substituants en para, a été obtenue. Le chapitre IV décrit la synthèse et la caractérisation des complexes dinucléaires du Manganèse(II) correspondants. Le chapitre V présente une étude RPE du complexe [(Bpmp)Mn2(Oac)2](ClO4). Une démarche originale pour la détermination des paramètres de spins des états S a permis l'obtention de simulations d'excellentes qualités d'une série de spectres en fonction de la température en bandes X et Q. Une étude de ce composé à haut champ a été initiée. Le chapitre VI décrit le stockage d'au moins trois équivalents oxydants à partir de complexes mononucléaires du Manganèse(II). Au cours de ces études, la structure par diffraction des rayons X du complexe [(TPEN)Mn(m-OAc)Mn(TPEN)](ClO4)3 a été résoluePhotosynthesis is a complex reaction that leads to the conversion of light energy to chemical energy. Chapter I proposes a review of the up-to-date knowledge of the natural system. The work described thereafter deals with the synthesis of Ruthenium-Manganese complexes, as model compounds of the electron transfer for Photosystem II. Following a first synthetic route, described in chapter II, we obtained a mixture of two species. Although the latter could not be separated, analysis of the mixture with a variety of spectroscopic techniques led to the identification of a RuMn2 triad and a Ru2Mn complex. We then developped two new strategies toward the synthesis of a [(Bipy)2Ru(PyN3)-BpmpH]+ moiety, capable of chelating two Manganese ions. In the first approach, protecting the phenolic oxygen of NH2BpmpH via the formation of a Zinc dimer allowed the coupling reaction of the amine with an acyl chloride to proceed efficiently. In the second approach, NH2Ar(DPA)2 is first reacted with an acyl chloride bearing the Ruthenium complex, then an aromatic oxydation of the xylene ring is performed. During these studies, a serie of RBpmpH ligands, only differing one another by the electronic properties of the para group, were isolated. Syntheses and characterization of the corresponding dinuclear Manganese(II) complexes are summed up in chapter IV. Chapter V deals with EPR studies of the [(Bpmp)Mn2(OAc)2](ClO4) complex. We developed a new approach for the determination of the spin parameters of the S-state resulting from the magnetic interaction between the two Manganese(II) ions, which led to very accurate simulation of X- and Q-band EPR spectra and their temperature dependance. Preliminary results on high field experiments were obtained. To conclude, chapter VI reports on the storage of up to three oxidative equivalents starting with Manganese(II) complexes. During the course of these studies, X-ray structure of the [(TPEN)Mn(m-OAc)Mn(TPEN)](ClO4)3 complex was established
15
Balatbat, Richard Vincent S. "An Investigation of Damage Arrestment Devices Application with Fastener/Hole Interaction." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/402.
Анотація:
This thesis presents a parametric study on the effects of how damage arrestment devices application interacts with a fastener in a composite sandwich panel. The primary objective of the damage arrestment device was to prevent the failure of the composite face sheet, such as crack propagation, around the hole/fastener joint. The damage arrestment devices are made of composite strips that are inserted under the face sheet to increase the overall structural strength of the panel and to prevent the propagation of failure along the hole. This was supposed to be a quicker and stronger alternative to potted inserts for composite sandwich panels for designer. The manufacturing curing cycle of the composite sandwich specimens has been carried out by using a Tetrahedron Composite Air Press. The press has been used to fabricate composite sandwich panels by applying constant pressure and variable heat to create panels with dimensions of 5” x 2” x .552”. The panels were stacked using a polyurethane foam, Last-A-Foam FR-6710 with two layers of a carbon-fiber/epoxy weave, LTM45, on both sides of the foam. The specimens were loaded under a compressive strain of 0.5 mm/min. The damage arrestment devices’ thickness was varied and tested under both monotonic and fatigue loading. The experimental results indicate that as the thickness of the device increased the overall strength of the part increased at a parabolic curve with it topping at a thickness of 0.065” and a strength increase of 109%. Under fatigue loading, a control group test case and damage arrestment device configuration case was tested. The experimental results indicate that both cases have similar fatigue trends but shows that the damage arrestment specimens are stronger due to the increase of structural strength. The experimental results were compared with numerical results or Finite Element Model. The results showed that numerical results can capture the linear or elastic portion of the experimental results having identical Elastic Modulus values. The models do differ in the maximum displacement of the specimen and the failure mode around the hole of the composite sandwich panel. The discrepancy in displacement and the failure mode was attributed to inaccurate loading on the hole of the composite sandwich panel and non-linear modeling of the solution. The correlation between the FEM and the experimental data was good enough in predicting the trends of the composite sandwich panels.
16
Von, Solms Charlayn Imogen. "A catalogue of shapes: a composite object portrait of an oral-formulaic Homer." Doctoral thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/15765.
Анотація:
Includes bibliographical referencesThe thesis identifies an equivalence between two seemingly disparate art-forms - Homeric poetry (the Iliad and the Odyssey) and sculptural assemblage. The synthesis of form and content achieved by the re-organization, manipulation, and transformation of pre-existing components in the theory of an oral-formulaic Homer is explored by means of a practical application of sculptural assemblage. The thesis proposes that Homeric poetics and sculptural assemblage are sufficiently similar in terms of structure, methodology, and interpretive processes, to enable a sculptural evocation of the participatory interpretive aspects of Homeric composition in performance that is comprehensible to a contemporary audience. The development of an iconography of an oral-formulaic Homer is expressed in a series of twelve sculptural assemblages entitled A Catalogue of Shapes 2010-13. These sculptures are composite object portraits of twelve Homeric characters. The creation of this catalogue of characters was informed by core structural, compositional, and conceptual aspects of the Iliadic Catalogue of Ships as a reflexive site of artistic self-awareness. A Catalogue of Shapes therefore represents a composite object portrait of an oral-formulaic Homer. The representational system underlying A Catalogue of Shapes incorporates complex connotative allusions achieved by the manipulation of symbolically-invested materials, objects, and forms to reflect the compositional strategy underlying Homeric poetics. As an 'aesthetic translation' this series of sculptural assemblages comprises the creative and contextual re-interpretation of attributes characteristic of the form and content of an existing text/artwork, by means of creating another. It is both an autonomous artwork and an extension of an existing creative tradition.
17
Lyengar, Nirmal. "Failure analysis of a quasi-isotropic laminated composite plate with a hole in compression /." This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-07102009-040536/.
18
BARBOSA, Cintya D' Angeles do Espirito Santo. "Polímeros de coordenação homo/heterometálicos baseados em Pb2+ e Eu3+: estrutura e propriedades fotofísicas." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/23468.
Анотація:
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CAPES, CNPQ, INCT
A luminescência de sólidos é uma área da ciência amplamente investigada no meio científico. Isso porque, os materiais que exibem essa propriedade possuem uma gama de aplicações que contempla desde o desenvolvimento de dispositivos ótico-eletrônicos até o uso em biotecnologia. Nesse sentido, a proposta do presente estudo foi investigar o comportamento morfológico, estrutural e fotofísico dos polímeros de coordenação (PC) [Pb(BDC)]n e Eu2(BDC)3(H2O)4, bem como de uma nova série de PC heterometálicos (HPCS) do tipo Pb1xEux – BDC (x = 0,05, 0,10, 0,25 e 0,50) BDC = 1,4-benzenodicarboxílico. O PC [Pb(BDC)]n apresentou fosforescência à temperatura ambiente. Os polímeros de coordenação heterometálicos desenvolvidos neste trabalho exibiram mudança de estrutura cristalina frente à inserção de íons európio. Para x <0,25 os íons Eu3+substituem os Pb2+ na estrutura, assim os HCPs Pb0,95Eu0,05 – BDC e Pb0,90Eu0,10 – BDC são isoestruturais a rede cristalina [Pb(BDC)]n. Por outro lado, o HPC Pb0,50Eu0,50 – BDC é isoestrutural ao PC Eu2(BDC)3(H2O)4. Em particular, o composto Pb0,75Eu0,25 – BDC apresentou tanto a fase do PC [Pb(BDC)]n quanto do Eu2(BDC)3(H2O)4). Essas fases no HCP Pb0,75Eu0,25 – BDC foram identificadas através de espectroscopia resolvida no tempo e por excitação seletiva utilizando uma metodologia diferenciada. De modo geral, todos os materiais sintetizados apresentaram rendimento quântico significativo, sendo que o HCP Pb0,75Eu0,25 – BDC exibiu o maior valor, 69 ± 7% (λ = 315 nm). Um estudo do efeito da temperatura foi realizado para o composto Eu2(BDC)3(H2O)4, e os dados mostraram que a sensibilidade térmica pode ser acompanhada no espectro de emissão através do deslocamento da transição 5D0→7F0, assim como pela mudança no perfil espectral da transição 5D0→7F2. Esses resultados sugerem que o PC Eu2(BDC)3(H2O)4 é um material promissor para aplicações em sensores de temperatura.
The luminescence of solids is an area of science widely investigated in the scientific community. This is because the materials that exhibit this property have a range of applications, including since the development of optical-electronic devices until use in biotechnology. Herein, the present work aims to investigate the morphological, structural and photophysical behavior of coordination polymers (PC) [Pb(BDC)]n and Eu2(BDC)3(H2O)4, as well as a new series of heterometallic PC (HPCS) Pb1-xEux – BDC ((x = 0,05, 0,10, 0,25 e 0,50), BDC = 1,4-benzenedicarboxylic. The PC [Pb(BDC)]n exhibits phosphorescence at room temperature. The heterometallic coordination polymers developed in this work exhibited changes in crystalline structure across the insertion of europium ions. For x < 0,25 the Eu3+ ions replace the Pb2+ in the structure, so the Pb0,95Eu0,05 – BDC and Pb0,90Eu0,10 – BDC are isostructural crystalline network [Pb(BDC)]n. Moreover, the sample HPC Pb0,50Eu0,50 – BDC is isostructural to the PC Eu2(BDC)3(H2O)4. In particular, the compound Pb0,75Eu0,25 – BDC showed both the phase of PC[Pb(BDC)]n much of Eu2(BDC)3(H2O)4. These phases in HCP Pb0,75Eu0,25 – BDC were identified by time-resolved spectroscopy and the selective excitation using a different methodology. In general, all the synthesized material showed the mean quantum yield, and the HCP Pb0,75Eu0,25 – BDC exhibited the highest value, 69 ± 7% (λ = 315 nm). A study of the temperature effect was performed for Eu2(BDC)3(H2O)4 compound and the results showed that the thermal sensitivity can be monitored in the emission spectrum by shifting the transition 5D0 → 7F0, as well as by the change in spectral profile of the transition 5D0 → 7F2. These results suggest that PC Eu2(BDC)3(H2O)4 is a promising material for applications in temperature sensors.
19
Stone, Daniel Paul. "The influence of ply orientation on the open-hole tension strength of composite laminates." Online access for everyone, 2008. http://www.dissertations.wsu.edu/Thesis/Spring2008/d_stone_042208.pdf.
20
Nixon-Pearson, Oliver James. "An investigation into the fatigue damage development in open- and bolted-hole composite laminates." Thesis, University of Bristol, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.652047.
Анотація:
There is a significant amount of work in the open literature regarding final failure of notched composite laminates, however there has been rather less characterisation of sub-critical damage prior to final failure, particularly under fatigue loading conditions_ A previous investigation into the static tensile strengths of scaled open-hole specimens showed three distinct failure modes which were either matrix- or fibre-dominated. Three open-hole specimen configurations which exhibited clear examples of these failure modes were chosen for the fatigue investigation. The primary objective of this thesis was to introduce a detailed experimental investigation into the sub-critical damage prior to specimen failure by interrupting fatigue tests part way through the decrease in stiffness with increasing number of cycles. X-ray computed tomography (CT) was carried out for the interrupted test specimens in order to establish the damage development. In some cases a different failure mode is observed under fatigue loading to the quasi-static cases. It is shown how the role of delamination is critical in fatigue even when it may not dominate in quasi-static tests. Cohesive element models in finite element analysis have been shown to be effective at predicting delamination failure, including fatigue formulations. These have largely been applied to simple configurations such as the Double Cantilever Beam (DCB) specimen. The University of Bristol fatigue cohesive formulation has been applied to models of the open-hole tests to predict the damage seen in interrupted fatigue test specimens. This is the first such application of fatigue cohesive element models to complex cases involving matrix cracks, delaminations and their interactions.
21
Iyengar, Nirmal. "Failure analysis of a quasi-isotropic laminated composite plate with a hole in compression." Thesis, Virginia Tech, 1992. http://hdl.handle.net/10919/43638.
Анотація:
The ability to predict failure of laminated composites in compression has been doggedly pursued by researchers for many years. Most have, to a limited extent, been able to predict failure for a narrow range of laminates. No means, as yet, exist for predicting the strength of generic laminates under various load conditions. Of primary concern has been the need to establish the mode at failure in compression. Even this has been known to vary for fiber and matrix dominated laminates.
This study has been carried out to analyze the failure of specimens with a hole made of laminates with various quasi-isotropic stacking sequences. Different stacking sequences are achieved by rotating a [±45/90/0]s stacking sequence laminate as a whole with respect to the loading axis of the specimens. Two- and three-dimensional finite element models, using commercial packages, were generated to evaluate the stresses in the region of the hole. Two different compressive failure prediction techniques based on distinctly different failure modes have been used. The validity of these techniques was measured against experimental data of quasi-isotropic specimens tested. To investigate the applicability of the failure criteria for different laminated composite plates, analyses were repeated for specimens with different stacking sequences resulting from the rotation of the laminate.
The study shows the need for the use of three-dimensional analysis of the stress state in the vicinity of the hole in order to be able to accurately predict failure. It also shows that no one mode of failure is responsible for limiting the strength for all laminate orientations but rather the mode changes with change in stacking sequence. The failure of the laminate with a hole was seen to be very sensitive to the stacking sequence. Experimental data presented also shows that the peak strength obtainable from the laminate analyzed, [±45/90/0]s, is going to be in the off-axis configuration rather than on-axis placement of the stacking sequence with respect to the loading direction.Master of Science
22
Chowdhury, Rajib. "Frequency scanned composite right-left handed leaky-weave antennas in cognitive radio enabled long term evolution advanced home eNode-Bs." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110409.
Анотація:
Long Term Evolution Advanced (LTE-A) is the further evolution to Long Term Evolution (LTE), a standard defined by the 3rd Generation Partnership Project (3GPP). LTE-A meets or surpasses the International Mobile Telecommunications Advanced (IMT-Advanced) requirements defined by the International Telecommunication Union (ITU). The capacity, standardized data-rates and low-cost deployments are concerns challenging the flexibility of LTE and beyond in LTE-A. For instance, providing high data rates over a large portion of the cell entails the usage of high bandwidth, which is limited and/or often wasted. Cognitive radio (CR) can contribute in addressing this mean through its capability to sense, learn, and autonomously adapt to its environment in order to optimize usage of spectrum (licensed and unlicensed). Also, it is known that a small distance between transmitter and receiver in a wireless system increases the capacity of this link and creates dual benefits of higher quality and more spatial reuse. Overlaying femotcells in legacy macro-cellular networks can thus be beneficial. In LTE-Advanced, femtocell access points are referred to as Home eNode-Bs (HeNBs). Such user installed devices communicate with the cellular network over a broadband backhaul such as Digital Subscriber Line (DSL) or a separate radio frequency (RF) backhaul channel. Logically in femtocell solutions, the need for compactness also turns out to be far greater for antennas. Hence triggers the idea of applying metamaterials, i.e., artificial, effectively homogeneous materials exhibiting unusual properties not readily available in nature. This thesis presents the design and analysis of a frequency scanned Composite Right-Left Handed (CRLH) Leaky-Wave Antenna (LWA) in a CR enabled HeNB. The antenna is designed with wire-bonded interdigital capacitors (WBIDC). This CRLH LWA is proposed to be used as a secondary antenna to support bandwidth-hungry applications of primary or secondary users within the femtocell, at its edge and in cooperation with its neighboring sites. Results exhibit that backfire to endfire radiation patterns between -60 and 60 degree angles are achievable at the azimuth plane between 2.2 and 3.25 GHz, respectively. Broadside radiation is achieved at 2.6 GHz, which accommodates a frequency-division duplexing (FDD) band 7 in LTE on the downlink (DL).Long Term Evolution Advanced (LTE-A) est la poursuite de Long Term Evolution (LTE), un standard défini par 3rd Generation Partnership Project (3GPP). LTE-A atteint ou dépasse les requis définis par International Telecommunication Union (ITU) du International Mobile Telecommunications Advanced (IMT-Advanced). La capacité, les taux de données normalisées et les bas coûts de déploiements sont des préoccupations contestant la souplesse de LTE et au-delà dans LTE-A. Par exemple, en fournissant des débits élevés sur une grande partie de la cellule implique l'utilisation de la bande passante élevée. Cela est limitée et/ou souvent gaspillée. La Radio Cognitive (CR) peut donc contribuer par sa capacité de détecter, d'apprendre, et de manière autonome, s'adapter à son environnement afin d'optimiser l'utilisation du spectre (sans licence). En outre, il est connu que d'une faible distance entre l'émetteur et le récepteur dans un système sans fil augmente la capacité de ce lien et crée un double avantage de meilleure qualité et plus de réutilisation spatiale. L'approche femtocell peut donc être bénéfique. Sous LTE-Advanced, les points d'accès femtocell sont appelés Home eNode-Bs (HeNBs). Ces dispositifs peuvent communiquer avec le réseau cellulaire sur une liaison terrestre à large bande tels que Digital Subscriber Line (DSL) ou sous une fréquence radio (RF) canal backhaul. En conséquence, la nécessité de compacité se révèle d'être beaucoup plus importante pour ses antennes. Et voici ce qui déclenche l'idée de l'application de métamatériaux, matériaux artificiels effectivement homogène présentant des propriétés inhabituelles qui ne sont pas disponibles dans la nature. Cette thèse présente la conception et l'analyse d'une Composite Right-Left Handed (CRLH) Leaky-Wave Antenna (LWA) dans une CR permis dans la HeNB. L'antenne est aussi conçue avec du fil-collé condensateurs interdigitaux (WBIDC). Cette CRLH LWA est proposée pour être utilisée comme une antenne secondaire pour supporter des applications gourmandes en bande passante des utilisateurs primaire ou secondaire dans le femtocell, à son bord et en coopération avec ses sites voisins. Les résultats présentées démontrent que les diagrammes de rayonnement sont réalisables aux angles de -60 à 60 degrés au plan d'azimut entre respectivement, 2.2 et 3.25 GHz. Rayonnement broadside est réalisé à 2.6 GHz. Cela respecte la bande 7 du frequency division duplexing (FDD) de LTE sur la liaison descendante.
23
Xia, Tian. "INVESTIGATION OF DRILLING PERFORMANCE IN CRYOGENIC DRILLING ON CFRP COMPOSITE LAMINATES." UKnowledge, 2014. http://uknowledge.uky.edu/me_etds/36.
Анотація:
In recent years, there has been a substantial growth in the application of carbon fiber reinforced plastic (CFRP) composite materials in automobile and aerospace industries due to their superior properties such as lightweight, high strength, excellent corrosion resistance, and minimal fatigue concerns. The present study evaluates the drilling performance of woven carbon fiber reinforced plastics under both dry and cryogenic cooling conditions using uncoated solid carbide drill with a through-hole for coolant application.
The effects of the cooling conditions and the cutting parameters on drilling performance in drilling CFRP were evaluated in terms of generated thrust force, torque, cutting edge radius, outer corner flank wear, hole quality (including surface roughness, diameter error, roundness, delamination, burr formation, sub-surface quality). Both cooling conditions and cutting parameters were found to influence the thrust force and torque at different levels. The thrust force and the torque are higher in cryogenic cooling under all cutting parameters. In most of the cases, cryogenic drilling gives better bore-hole quality with lower surface roughness, more accurate diameter, less burr generation, better sub-surface quality, etc. Also, the tool-wear rates measured in drilling shows that cryogenic drilling produces less tool-wear than dry drilling does.
24
McClain, Sandra Clemmons. "The solo vocal repertoire of Mary Carlisle Howe with stylistic and interpretive analyses of selected works /." Access Digital Full Text version, 1992. http://pocketknowledge.tc.columbia.edu/home.php/bybib/11229342.
Анотація:
Thesis (Ed.D.)--Teachers College, Columbia University, 1992.Typescript; issued also on microfilm. Sponsor: Jan Eric Douglas. Dissertation Committee: Harold F. Abeles. Includes bibliographical references (leaves 215-217).
25
Mollenhauer, David Hilton. "Interlaminar Deformation at a Hole in Laminated Composites: A Detailed Experimental Investigation Using Moire Interferometry." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30680.
Анотація:
The deformation on cylindrical surfaces of holes in tensile loaded laminated composite specimens was measured using new moire interferometry techniques. These new techniques were developed and evaluated using a 7075-T6 aluminum control specimen. Grating replication techniques were developed for replicating high quality diffraction gratings onto the cylindrical surfaces of holes. Replicas of the cylindrical specimen gratings (undeformed and deformed) were fabricated onto circular steel sectors. Narrow angular regions of these sector gratings were directly evaluated in a moire interferometer. This moire interferometry approach eliminated potential sources of error associated with other moire interferometry approaches.
Two composite tensile specimens, fabricated from IM7/5250-4 pre-preg with ply layups of [0₄/90₄]3s and [+30₂/-30₂/90₄]3s, were examined using the newly developed moire interferometry techniques. Circumferential and thickness direction displacement fringe patterns (each 3 degrees wide) were assembled into 90 degrees wide mosaics around the hole periphery for both composite specimens. Distributions of strain were calculated with high confidence on a sub-ply basis at select angular locations. Measured strain behavior was complex and displayed ply-by-ply trends. Large ply related variations in the circumferential strain were observed at certain angular locations around the periphery of the holes in both composites. Extremely large ply-by-ply variations of the shear strain were also documented in both composites. Peak values of shear strain approached 30 times the applied far-field axial strain. Post-loaded viscoelastic shearing strains were recorded that were associated with the regions of large load-induced shearing strains. Large ply-grouping related variations in the thickness direction strain were observed in the [+30₂/-30₂/90₄]3s specimen. An important large-scale trend was observed where the thickness direction strain tended to be more tensile near the outside faces of the laminate than near the mid-ply region. The measured strains were compared with the three-dimensional analysis technique known as Spline Variational Elastic Laminate Technology (SVELT), resulting in a very close match and corroborating the usefulness of SVELT.Ph. D.
26
Bouchet, Jullien. "Ingénierie de l'intéraction multimodale en entrée : approche à composants ICARE." Grenoble 1, 2006. http://www.theses.fr/2006GRE10228.
Анотація:
Depuis les travaux fondateurs de R. Bolt« Mets ça là » combinant la voix et le geste, les modalités d'interaction se sont multipliés, diversifiés et améliorés. Les récents paradigmes d'interaction comme les interfaces tangibles incarnées ou la réalité augmentée, couplés aux progrès des systèmes de localisation, à la miniaturisation des dispositifs, à la qualité des réseaux sans fils, à l'amélioration de la reconnaissance de la parole ou de gestes ouvrent un vaste champ de possibilités d'interaction pour les systèmes multimodaux. Dans ce contexte, et bien que de nombreux systèmes multimodaux soient disponibles, leur développement et leur maintien restent encore des tâches difficiles, notamment par manque de réutilisabilité de l'existant. Ce travail de thèse aborde ce problème de conception et de développement pour la multimodalité en entrée (de l'utilisateur vers le système informatique). Nous décrivons un modèle conceptuel de la multimodalité qui organise dans un canevas unificateur les modalités et leurs formes de combinaison. Basé sur ce modèle, nous définissons une approche générique à composants logiciels, notée ICARE, facilitant et accélérant la conception, le développement et le maintien des interfaces multimodales. Nous démontrons l'apport de cette approche par l'outil ICARE qui est une opérationnalisation de notre approche à composants. Un éditeur graphique est fourni, simplifiant la phase d'assemblage des composants et générant automatiquement le code correspondant à l'interaction multimodale. Cinq systèmes multimodaux aux caractéristiques distinctes (systèmes de réalité augmentée, de virtualité augmentée et mobiles) ont été développés avec l'outil ICAREThe area of multimodal interaction has expanded rapidly since the seminal "Put that there" demonstrator of R. BoIt that combines speech and gesture. Ln parallel with the development of the Graphical User Interface technology, natural language processing and gesture recognition have made significant progress. Ln addition, recent interaction paradigms such as tangible and embodied user interfaces as weIl as augmented reality open a vast world of possibilities for interaction modalities. Significant achievements have been made in terms of both modalities and real multimodal systems. Although several muItimodal systems have been built, their design and development still remains a difficult task particularly because of a lack of reusability. Ln this thesis we address this problem of design and development for input multimodal interfaces (from the user to the system). We describe a conceptual model ofmultimodality as a unified framework for modalities and combinations of modalities. Based on this conceptual model, we define a generic component-based approach called ICARE which allows the easy and rapid design, development and maintenance of multimodal interfaces. We have developed the ICARE tool to prove the usefulness of our component-based approach. The ICARE tool is a graphical platform that enables the designer/developer to graphically manipulate and assemble ICARE software components in order to specify the muItimodal interaction. From this specification, the code of the multimodal interaction is automatically generated. Five multimodal systems with different characteristics (augmented virtualitv/realitv, mobile systems) have been develooed with the ICARE too1
27
Paredes, Farfan Gustavo Alonso, Neira Verastegui Felix Moises, Ramos Leonardo Nikolai Vinces, and Oliden Martinez Jose Fortunato. "Design of a system for the external washing and winding of fire hoses composed of a polyester and rubber jacket." Institute of Electrical and Electronics Engineers Inc, 2020. http://hdl.handle.net/10757/656627.
Анотація:
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.This work describes the design of an external cleaning system for fire hoses with an external polyester or rubber jacket. This device is intended as a tool for simple and effective external cleaning. Within the capabilities of the equipment is the washing and winding of a hose. This is made up of a washing chamber, which contains a group of sprinklers inside with a brushing system and a winding mechanism with a platform designed to carry out the type of winding snail or single donut. Cleaning can be applied to both types of coatings with the action of a selector switch, the variables involved are adjusted accordingly. The system aims to perform its functions without damaging the composition of the hose lining material, in addition to reducing the space required during cleaning.
28
Sundaramurthy, Surya Narayanan. "New Sensing Techniques for Structural Health Monitoring of Hydraulic Hose, Composite Panels, and Biodegradable Metal Implants." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1307105130.
29
Treasurer, Paul James. "Characterization and Analysis of Damage Progression in Non-Traditional Composite Laminates With Circular Holes." Thesis, Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/13989.
Анотація:
Carbon Fiber / Epoxy Laminates are increasingly being used in the primary structure of aircraft. To make effective use these materials, it is necessary to consider the ability of a laminate to resist damage, as well as material strength and stiffness. A possible means for improving damage tolerance is the use of non-traditional composite laminates, in which the longitudinal 0 plies are replaced with 5 or 10 plies. The main objectives of this collaborative Georgia Tech / Boeing research was the characterization of these non-traditional laminates, and the determination of appropriate lamina-level analytical techniques that are capable of predicting the changes caused by the use of slightly off-axis longitudinal plies. A quasi-isotropic [45/90/-45/theta/45/90/-45/-theta]s and hard [45/theta/-45/theta/90/45]s lay-up, where theta =0,5 or 10, were tested in open hole tension, filled hole tension, open hole compression, single shear bearing, and unnotched tension. These coupon level tests illustrated the effects of lay-up, notch constraint, and load type on traditional and non-traditional laminates. Die penetrant enhanced in-situ radiography was performed to determine the extent of damage suppression. The use of non-traditional laminates was found to reduce longitudinal ply cracking and delamination, with significant effect on the stress distribution around the notch. The use of non-traditional laminates also resulted in a 15%-20% improvement in bearing strength of the traditional laminates. Several predictive techniques were implemented to evaluate their ability to predict the effect of slight changes in ply orientations. A progressive damage model was written to compare Tsai-Wu, Hashin, and Maximum Stress unnotched strength criterion. Additionally, several semi-empirical failure theories for notched strength prediction were compared with linear and bi-linear cohesive zone models to determine applicability to non-traditional laminates.
30
Puig, Serrano Jordi. "Transferència electrònica i mecanisme associat a l'oxidació de composts homo-bimetàl·lics (M= Rh(I), Ir(I)) amb ponts alquiltiolat. Efectes de solvatació." Doctoral thesis, Universitat Autònoma de Barcelona, 2001. http://hdl.handle.net/10803/3124.
Анотація:
Les reaccions de transferència electrònica engloben bona part dels processos químics i, en conseqüència, presenten un gran interès pel químic molecular. En l'estudi de sistemes bimetàl·lics, especialment en aquells sistemes on els dos centres metàl·lics es troben a distàncies properes però lleugerament majors a la d'enllaç, bona part d'aquest interès es centra en la reactivitat en assistència bimetàl·lica. Donada la naturalesa, fonamentalment electrònica, de la interacció bimetàl·lica, les metodologies de l'electroquímica molecular (Voltametria Cíclica, Coulombimetria i tècniques derivades) són adequades per a realitzar l'estudi químico-físic del procés de transferència electrònica i, en conseqüència, permeten aportar una valuosa informació, tant a nivell cinètic com termodinàmic. L'oxidació monoelectrònica del sistema bimetàl·lic de partida (oxidació centrada fonamentalment en els metalls, inicialment amb estructura electrònica formal d8d8) genera un complex de valència mixta, formalment d8d7. L'estudi electroquímic indica una important deslocalització de valència entre ambdós centres metàl·lics (d7.5d7.5) consistent amb l'anàlisi espectroscòpica. En base a aspectes cinètics i termodinàmics de la transferència electrònica en diferents medis, s'estableix que aquesta manifesta clars efectes de solvatació, ambdós, a nivell estàtic i dinàmic (fricció dielèctrica).
Els efectes de solvatació resulten inductors de la reactivitat del compost de valència mixta electrogenerat envers un procés de reestructuració (isomerització redox intramolecular) resultat de la reducció formal dels centres metàl·lics (recuperant-se l'estructura electrònica formal d8d8 pels centres metàl·lics) i l'oxidació dels lligands ponts connectors. L'estudi estableix que aquesta isomerització redox té lloc en resposta a la solvatació d'una única molècula d'agent solvantant, probablement mitjançant la localització de l'espin en un dels dos centres metàl·lics.
El treball aporta l'estudi cinètic de la dependència de l'equilibri entre els confòrmers syn-endo vs syn-exo amb la solvatació.
Finalment, la detecció d'intermedis (electroquímica i espectroscòpica) i la caracterització estructural del producte final d'evolució permet proposar un mecanisme global i definir així la tendència intrínsica del sistema davant l'oxidació.
Electron transfer reactions play a key rol in many chemical processes and, consequently, are subject of great interest for molecular chemists. In the case of bimetallic systems, specially those contain at short (but higher than the bond) metal-metal distance, the main interest is focused on the so called bimetallic assisted reactivity. Due to the intrinsic nature - mainly electronic - of bimetallic interaction, molecular electrochemistry methodologies (e.g. Cyclic Voltammetry, Coulometry and related) allows to achieve suitable kinetic and thermodynamic data, even to describe the electron transfer particularities .
The initial one-electron oxidation occurs formally centered on the metal atoms. It implies the generation of a mixed valence cation complex, formally d7d8. The electrochemical description indicates an important spin delocalization (d7.5d7.5) among the two centers. Spectroscopical data agree with this interpretation. On the basis of kinetics and thermodynamical data for the electron transfer reaction in different media, solvation effects are described as static. At least in a case an important dynamic (dielectric friction) contribution was also observed.
Solvation effects are inductors on the reactivity of the electrogenerated mixed-valence cation upon an internal estructuration process (intramolecular redox isomerization), yielding to the formal reduction of the metal centers (the formal d8d8 electronic situation is recovered) accompained by the bridging ligands oxidation. Only a molecule of solvating agent causes the redox isomerization, probably by means of the spin localization on mainly one of the metal centers.
This work also include an approach to the solvation dependence on syn-endo vs syn-exo conformational equilibrium, previous to the anodic charge transfer process.
Finally, the intermediates detection (by electrochemical and spectroscopical methods) has been available, in almost the critical cases. Also the fully structure characterization of the final evolution product has been achieved. Thus, the experimental data allows us to propose a detailed mechanism, moreover, to define the general treats of the intrinsic system tende.
31
Dewing, Wende L. "Perception of Color Quality for Natural Images Viewed, Edited, and Printed Within the Context of a Home Digital Color Imaging System." Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/26232.
Анотація:
Within the home environment there exits a host of digital color imaging (DCI) system configurations. The combination of devices and software at the consumerâ s desktop with devices and services at a remote location (e.g., Print at Kodak), creates a complex interaction of device, contextual, and observer characteristics. In particular, the cathode-ray tube (CRT) display has the potential to influence consumersâ perceptions of image quality and their subsequent image manipulation activities. Depending on the inherent color bias and apparent contrast of the CRT, extensive image manipulation may occur, significantly altering the digital values of the image. Output generated by a remote printer will reflect any image manipulation undertaken by the consumer. If manipulation was extensive, what the consumer receives from a remote printer will appear quite different from the softcopy version and thus, may be deemed unacceptable.
This research was designed to address the softcopy-hardcopy matching issues that arise from the home DCI system configuration just described. The primary study examined how the CRT display influenced perceived color quality of photographs generated at two points in a DCI system; on-screen photographs (softcopy) and photographic quality prints (hardcopy). CRT gamma, color temperature, and excitation purity were manipulated using an orthogonal, blocked, central composite design. Twenty-two Eastman Kodak Company employees viewed 6 photographs under each of the 15 CRT conditions. Participants rated the color quality of each softcopy photograph, then were given an opportunity to edit color balance, brightness, and contrast for each photograph. The edited photos were printed and rated once again for color quality and acceptability.
Results indicated that monitor calibration influenced perceived softcopy color quality, softcopy editing behavior, and subsequent perceived hardcopy color quality. Perception of softcopy color quality ratings was determined predominantly by the CRT gamma level. Participants responded to CRT color balance differences through their editing behavior. In some cases, edits were large enough to significantly and negatively impact perceived hardcopy color quality. Gamma in particular, was the most significant predictor of hardcopy color quality ratings and rejection rates.
Additional differences were observed between first- and third-party photographs.
Results from this research may be applied to the development of monitor calibration tools, scene balancing algorithms, and software, for the purpose of accommodating consumer image manipulation behavior, in the context of the home DCI system presented herein.Ph. D.
32
Routenberg, Scott Kevin. "Americana Suite: A Composition for Full Orchestra, Big Band, and Jazz Chamber Ensembles Inspired by American Master Paintings." Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_dissertations/80.
Анотація:
Americana Suite is a seven movement musical composition inspired by nineteenth and early twentieth century American master paintings. Representative artists from each of the major schools of American painting include Frederic Church, Winslow Homer, Mary Cassatt, Childe Hassam, George Bellows, Edward Hopper and Georgia O'Keeffe. Essentially pluralist in style, the suite is written for ensembles of varying size and genre, spanning from full orchestra and contemporary big band to intimate jazz chamber ensembles and electro-acoustic hybrids. Four of the seven movements are written for jazz ensembles and incorporate improvisation, while the other three orchestral movements explore romantic, impressionist and cinematic idioms. Historical summaries of each school, artist and painting are followed by detailed aesthetic and theoretical analyses of the respective movements. Harmonica virtuoso Howard Levy performs as a special guest artist.
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Mathison, Steve Richard. "Nonlinear analysis for the response and failure of compression- loaded angle-ply laminates with a hole." Thesis, Virginia Tech, 1987. http://hdl.handle.net/10919/45819.
Анотація:
The objective of this study was to determine the effect of nonlinear material behavior on the response and failure of unnotched and notched angle-ply laminates under uniaxial compressive loading. The endochronic theory was chosen as the constitutive theory to model the AS4/3502 graphite-epoxy material system.
Three-dimensional finite element analysis incorporating the endochronic theory was used to determine the stresses and strains in the laminates. An incremental/iterative initial strain algorithm was used in the finite element program. To increase computational efficiency, a 180° rotational symmetry relationship was utilized and the finite element program was vectorized to run on a super computer. Laminate response was compared to experiment revealing excellent agreement for both the unnotched and notched angle-ply laminates. Predicted stresses in the region of the hole were examined and are presented, comparing linear elastic analysis to the inelastic endochronic theory analysis.
A failure analysis of the unnotched and notched laminates was performed using the quadratic tensor polynomial. Predicted fracture loads compared well with experiment for the unnotched laminates, but were very conservative in comparison with experiments for the notched laminates.
Master of Science
34
Morris, Matt. "A history of Christchurch home gardening from colonisation to the Queen's visit: gardening culture in a particular society and environment." Thesis, University of Canterbury. School of Culture, Literature and Society, 2006. http://hdl.handle.net/10092/936.
Анотація:
Garden histories since the mid 1990s have increasingly turned to studies of vernacular gardens as sites of identity formation. More recently, the development of environmental history and specifically urban environmental history has started to show how vernacular gardening in suburban and urban spaces has contributed to changes in urban environments. Relatively little work on home gardening history in this sense has been undertaken in the New Zealand context, while in Australia such work is well underway. This study augments knowledge of home gardening history in New Zealand by focussing on one urban area, Christchurch, known both as the 'Garden City' and as 'one of the most English cities outside of England'. An examination of gardening literature over the period from European colonisation in 1850 to the first visit to the city by a reigning monarch in 1954 highlights changes in gardening tropes rather than particular garden fashions or elements. The four principal tropes of abundance, beauty, protection and sustenance, each supported with a particular kind of ritual-like garden competition, show how gardening discourses related to ideas about the maintenance of the social and cultural order. A more objective measure of attitudes to gardens is gained by examining 1823 property advertisements across the period. Categorised by suburb this analysis shows a level of gardening variation across the city. Following this analysis, case studies of four suburbs in three areas were undertaken. These were based primarily on oral histories and reveal the extent of gardening variation across the city, and the limited but significant effect that gardening discourses had on gardens. This suggests methodological problems with many studies of vernacular gardens, as well as opportunities for further studies. This thesis also demonstrates the value of home gardening histories to urban environmental history, particularly with regard to the former colonies of the British Empire.
35
Arshad, Mubeen. "Damage tolerance of 3D woven composites with weft binders." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/damage-tolerance-of-3d-woven-composites-with-weft-binders(2b1435bc-fdb7-47c3-b555-ca5ea2883b4b).html.
Анотація:
3D woven composites, due to the presence of through-thickness fibre bridging, have the potential to improve damage tolerance and at the same time to reduce the manufacturing costs. However, the ability to withstand damage depends on weave architecture as well as the geometry of individual tows. A substantial amount of research has been performed to understand in-plane properties as well as the performance of 3D woven composites exposed to impact loads, but there is limited research on the damage tolerance and notch sensitivity of 3D weaves and no work is reported on the damage tolerance of 3D weaves with a weft binding pattern. In view of the recent interest in 3D woven composites, the influence of weft binder on the tensile, open hole tensile, impact resistance and subsequent residual compressive strength properties and failure mechanisms of 3D woven composites was investigated against equivalent UD cross-ply laminate. Four different 3D woven architectures; layer-to-layer, angle interlocked, twill angle interlock and modified angle interlock structures were produced under identical weaving conditions. All the above mentioned tests were performed in both the warp and weft directions on 3D woven and UD cross-ply laminates. Stress concentration and yarn waviness due to through-thickness reinforcement led to lower mechanical properties compared with the UD cross-ply laminate. However, improved in-plane and damage tolerance properties of 3D woven composites under tensile loads were achieved by modifying the weave architecture. The influence of the weave architecture and binder yarn orientation on the notch insensitivity and damage tolerance of 3D woven composites was less significant for compressive loads. Despite the lower undamaged compression strength of 3D woven structures, their residual compressive strength was found to be superior to their equivalent UD cross-ply laminates. The lower rate of strength reduction in the 3D woven fabrics laminates was attributed to a crack bridging mechanism, effectively inhibiting delamination propagation.
36
Demus, Duana. "A composer by divine right a performance guide to Harry Burleigh's Saracen songs and Five songs of Laurence Hope /." Diss., Restricted to subscribing institutions, 2004. http://proquest.umi.com/pqdweb?did=790244721&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
37
Germain, Jérémy. "Évaluation des capacités prédictives d’un modèle avancé pour la prévision de la tenue de plaques stratifiées perforées." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASN004.
Анотація:
Ce travail porte sur la prévision de la tenue en traction de structures composites trouées et d’un stratifié d’unidirectionnel carbone/époxy de dernière génération. Cette thèse s’inscrit dans le projet MARCOS, piloté par l’ONERA et DASSAULT AVIATION.Elle consiste à proposer une approche de complexité maîtrisée permettant de prévoir la ruine de plaques perforées composites stratifiées afin de réduire le conservatisme des critères de rupture utilisés en bureau, et à valider l’approche proposée sur des configurations représentatives de celles utilisées dans l’industrie.Les campagnes d’essais de traction sur plaques trouées et leurs analyses disponibles dans la littérature montrent que la fissuration matricielle et le délaminage, sont des mécanismes ayant une influence sur la ruine. On s’appuiera tout d’abord sur une campagne d’essais mécaniques permettant de caractériser le matériau à l’étude.Les données de ces essais permettront l’identification d’un modèle de comportement, qui sera formulé à l’échelle du pli, et dont l’endommagement correspond à une densité de fissures. Les difficultés numériques associées à l’utilisation de modèles avancés dans un code de calcul par éléments-finis seront investiguées.Enfin, une vaste campagne d’essais ONERA/DASSAULT AVIATION, de traction sur plaques perforées mettra en évidence un effet de diamètre, comme il est classiquement observé, ainsi qu’un effet de largeur.Ce dernier consiste en l’augmentation de la contrainte macroscopique à rupture pour des rapports entre la largeur de plaque et le diamètre de trou supérieurs à 5. Ces aspects ont été peu investigués dans la littérature. On s’appuiera sur la riche instrumentation associée à cette campagne d’essais pour expliquer cet effet et évaluer les capacités prédictives de l’approche proposéeThis work focuses on laminated composite open-hole tensile strength prediction, with a new generation carbon/epoxy material. This PhD takes part in a project named MARCOS, led by ONERA and DASSAULT AVIATION.It aims at proposing a fair level of complexity approach to predict laminated composite open-hole tensile strength in order to reduce design office criteria conservatism and performing its validation on industrial test cases. Open-hole tensile test and analysis available in the scientific literature show that matrix cracking and delamination are two mechanisms acting on final failure. We will first perform a mechanical test campaign to characterize the studied material. A material model, written at the ply scale will be proposed.Damage is described thanks to a crack density variable, the model identification will rely on the experimental test results.Numerical difficulties occurring in finite-element computations using advanced approaches will be investigated.Then, an experimental open-hole tensile test campaign led by ONERA and DASSAULT AVIATION, will exhibit a hole size effect, as commonly observed on composite materials, but also a width effect. The width effect consists in a strength increase when the ratio between the open-hole width and the hole diameter is greater than 5 Very few studies focused on the width effect, hence, it will be investigated. We will then use the important instrumentation used on these test to explain this effect and evaluate the proposed approach predictive capabilities
38
Sabouret, Nicolas. "Étude de modèles de représentations, de requêtes et de raisonnement sur le fonctionnement des composants actifs pour l'interaction homme-machine." Phd thesis, Université Paris Sud - Paris XI, 2002. http://tel.archives-ouvertes.fr/tel-00002979.
Анотація:
Dans cette thèse, nous abordons le problème de la construction de réponses à des requêtes formelles modélisant les questions qu'un utilisateur humain peut poser concernant le fonctionnement d'un composant actif. Nous présentons d'abord un langage de programmation qui permet d'accéder en cours d'exécution à la description des actions du composant. Nous proposons ensuite un modèle de requêtes qui permet de représenter une large classe de question sur le fonctionnement et de prendre en compte des notions de bon sens issues de l'interaction en langage naturel. Nous proposons des algorithmes de construction de réponses pour ces requêtes formelles de bon sens. Nous étudions aussi le traitement des requêtes portant sur l'exécution passée du composant. Nous proposons une approche dynamique fondée sur l'extraction de comportement à partir des flux d'interaction. Enfin, nous montrons que notre travail peut être utilisé dans le web sémantique pour définir des pages dynamiques capables d'interagir avec les utilisateurs ordinaires, puis nous présentons l'implémentation de notre modèle dans le cadre du projet InterViews.
39
Jaud, Alexandre. "Croissance homo-épitaxiale VLS et étude du dopage au magnésium de GaN pour la protection périphérique de composants de puissance." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1181/document.
Анотація:
Dans le contexte de la protection périphérique des composants de puissance en GaN, nous avons exploré une voie originale pour réaliser l'homo-épitaxie localisée de GaN de type p, reposant sur une approche Vapeur-Liquide-Solide (VLS). Le cycle de croissance comprend 3 étapes successives. Dans un premier temps, du Ga est déposé par MOCVD, formant un réseau de gouttelettes de diamètres submicrométriques. Puis, du Mg est incorporé aux gouttelettes à partir de la phase gazeuse, en utilisant le précurseur (MeCP)2Mg. Enfin, les gouttelettes de Ga-Mg sont nitrurées à 500-700°C sous un flux de NH3 dilué dans un gaz porteur. À l'issue d'un cycle complet de croissance, on obtient systématiquement un réseau de plots et/ou d'anneaux de GaN, bien séparés. L'augmentation de la teneur en Mg dans les gouttes favorise un mécanisme de croissance purement VLS, à l'interface Liq/Sol (formation de plots), plutôt qu'une croissance le long de la ligne triple (formation d'anneaux). Ces structures de GaN présentent un caractère homo-épitaxial, mais une plus forte défectuosité que leur germe. En utilisant une approche multi-cycles, nous avons pu élaborer des films de GaN:Mg présentant des concentrations en Mg très élevées, contrôlables entre 3.1019 cm-3 et 8.1021 cm-3. Cependant, de fortes concentrations en impuretés C, H et O ont également été détectées dans ces films. Diverses voies ont été explorées, sans succès, pour tenter de réduire la contamination en O, d'un niveau rédhibitoire pour l'obtention d'un dopage de type p. En pratique, les films de GaN:Mg obtenus apparaissent très conducteurs de type n, pour des dopages au Mg modérés, et semi-isolants aux plus forts dopages. Différents matériaux de masques ont été testés en vue de localiser la croissanceFor peripheral protection of GaN power electronics devices, we have explored a new approach for performing localized homo-epitaxy of p-doped GaN, by implementing Vapor-Liquid-Solid (VLS) transport. The growth cycle includes three successive steps. At first, Ga is deposited onto the seed surface by MOCVD from TEG, resulting in an array of Ga droplets with submicrometric diameters. Then, Mg is incorporated into the droplets from the gas phase, using (MeCP)2Mg precursor. In the last step, Ga-Mg droplets are nitridated at 500-700°C in flowing ammonia diluted in a carrier gas.After one complete growth cycle, a network of well separated submicrometric GaN dots or ring-shaped features is systematically obtained. Increasing the Mg incorporation into the droplets drastically influences the growth mode, promoting a pure VLS growth mechanism, at the Liquid/Solid interface, versus growth at the triple line. Such GaN structures show a homo-epitaxial relationship with the seed, but a higher crystalline imperfection. Using a multi-cycles approach, GaN films could be obtained, with very high Mg concentrations tunable from 3.1019 to 8.1021 cm-3. Nevertheless, O, C and H impurities are also incorporated at high levels. Various approaches have been vainly investigated to try reducing O contamination level, prohibitive for obtaining p-type material. Actually, as-grown GaN:Mg films are n-type and highly conductive, for moderate Mg concentrations, and become semi-insulating at highest doping levels. Various masking materials have been tested for growth localization purpose
40
Déry, François. "Être homme, infirmier et heureux : les stratégies de vingt infirmiers en centre hospitalier pour composer avec la souffrance au travail." Doctoral thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/31153.
Анотація:
Le système de la santé au Québec est confronté depuis plusieurs décennies à des transformations structurelles et économiques importantes. Ces transformations engendrent des impacts sociaux notables sur le personnel du réseau de la santé, tels que des changements répétés de poste, des transferts d’équipe, une précarité d’emploi, voire parfois une perte d’emploi. Parmi les impacts psychologiques possibles, on relève une hausse du stress professionnel lié aux difficultés vécues au travail. Le stress professionnel, ou souffrance au travail, des infirmiers en centre hospitalier au Québec figure comme la problématique centrale étudiée dans le cadre de cette thèse. Les hommes se retrouvent en nombre restreint parmi les effectifs infirmiers, ce qui peut influencer la dynamique du stress professionnel vécu au sein de ce milieu de travail. Globalement, cette thèse a tout d’abord pour objectif de mieux comprendre les perceptions des infirmiers travaillant en milieu hospitalier quant aux sources de souffrance et de plaisir présents dans leur travail, pour ensuite nommer les moyens qu’ils prennent pour conjuguer avec les sources de souffrance. Plus généralement, la question principale de cette thèse va ainsi : que font les infirmiers pour bien vivre avec leur travail, et de quelle manière le fait d’être un homme influence cette situation ? Sur le plan théorique, la psychodynamique du travail de Dejours (1993) structure l’angle d’analyse de cette étude. Afin de compléter l’analyse des moyens efficaces pour contrer le stress et étudier les aspects relatifs au genre, la théorie de la salutogénèse d’Antonovsky (1979) et la théorie de la performativité de Butler (1990) ont été ajoutées au cadre théorique. Cette recherche qualitative de nature exploratoire utilise comme outil de collecte de données l’entrevue semi-dirigée, effectuée auprès de 20 infirmiers de différents centres hospitaliers du Québec. Les transcriptions ont été analysées à l’aide du logiciel QDA Miner. Les résultats de l’analyse permettent de constater tout d’abord que la notion de soin est centrale quant aux sources de plaisir nommées par les infirmiers interrogés, notamment par la capacité d’aider et de faire une différence dans la vie des personnes soignées. Au contraire, la situation économique et politique de la gestion du réseau de la santé figure comme un des éléments les plus stressants nommés par les répondants, cette situation étant perçue comme ayant des impacts de grande envergure sur le quotidien de l’emploi. Le travail d’équipe, pour sa part, occupe un rôle partagé, représentant autant une grande source de plaisir qu’une source de souffrance potentielle. Ensuite, les moyens les plus souvent utilisés par les répondants pour compenser la souffrance en milieu de travail sont le sport, les loisirs, le soutien social et la réorganisation des tâches. Enfin, concernant le rôle du genre masculin dans la dynamique de la souffrance au travail, les réponses données laissent entrevoir que le concept « d’être homme » est diversifié et loin de faire front uni auprès des répondants. Quelques éléments concordant dans les réponses concernent la pratique des soins infirmiers qui serait plus pragmatique et orientée vers les solutions lorsqu’elle est pratiquée par un homme. Les répondants démontrent que d’une part, la clientèle voit l’entrée des hommes dans la profession d’un bon oeil, et d’autre part, que les attentes des collègues féminines et des employeurs sur le rôle que doit occuper un infirmier de par son genre masculin reste en grande partie encore ancrées dans une image traditionnelle. L’ensemble de ces résultats suggère un urgent besoin d’ouverture de la part des employeurs d’inciter la collaboration des employés dans la recherche et l’application de moyens pour contrer la souffrance au travail. De plus, un changement de mentalité sur les divisions genrées entre infirmiers et infirmières reste à faire au cours des prochaines années, en vue d’en arriver à une véritable équité non-genrée.For several decades, the Quebec healthcare system has been confronted with major structural and economic transformations. These transformations have significant social impacts on health system staff, such as repeated job changes, shift work, job insecurity, and sometimes job loss. Possible psychological impacts include an increase of occupational stress. Occupational stress, or work suffering, of male nurses working in hospitals in Quebec is the central element studied in this thesis. Males remains a small minority in the nursing workforce, which may represent a source of stress in the workplace. Overall, sources of pleasure and suffering, ways to cope with suffering at work and male gender are the main concepts examined in this research. To access this information, semi-directed interviews were conducted with 20 male nurses from different hospitals in Quebec. The transcriptions were analyzed with the QDA Miner software, using Dejours'(1993) work psychodynamics theory. To complete the analysis of effective solutions against suffering at work as well as the role of gender, Antonovsky's (1979) theory of salutogenesis and Butler's (199) theory of performativity have been added to the theoretical framework. The results of the analysis show that the notion of care is central to the sources of pleasure for the respondents, precisely the ability to help and make a difference in the lives of patients. On the contrary, the economic and political situation of the management of the health network appears as one of the most stressful elements for the respondents, the latter having far-reaching impacts on daily work. Also, teamwork has a shared role, being both a source of pleasure and a source of potential suffering. Then, the most common solutions used by nurses to cope with suffering at work are sport, recreation, social support and reorganization of work tasks. Finally, regarding the role of the male gender in the dynamics of work-related suffering, the answers of the respondents indicated that the concept of being a man is very diversified. Some similar elements in the answers relate to the practice of nursing, which would be more pragmatic and solution-oriented when practiced by a man. The respondents, by their answers, show that, on the one hand, the clientele sees the entry of men as a good thing for the nursing profession, and on the other hand, that the expectations of the female colleagues and employer on the role that must occupy a male nurse remains strongly anchored in the traditional image of a man for these two actors. According to these findings, an urgent need remains in the employer's openness to collaborate with their employees in the search and the practical application of solutions to cope with the suffering at work.
41
Sabouret, Nicolas. "Etude de modèles de représentation, de requêtes et de raisonnement sur le fonctionnement des composants actifs pour l'interaction homme-machine." Paris 11, 2002. http://www.theses.fr/2002PA112290.
Анотація:
Nous abordons dans cette thèse le problème de la construction de réponses à des requêtes formelles modélisant des questions de bon sens posées par les utilisateurs ordinaires concernant le fonctionnement d'un composant actif. Les recherches actuelles dans la communauté du raisonnement sur les actions proposent de travailler sur une modélisation du système en logique pour répondre à des requêtes bien formées et ne prennent pas en compte l'existence de "notions de bon sens" utilisées par les utilisateurs ordinaires dans la formulation des questions. De plus, nous voulons pouvoir travailler directement sur le code du composant. Nous présentons tout d'abord un langage de programmation pour les composants actifs qui permet d'avoir accès en cours d'exécution à une description des actions et des données du composant. Nous présentons ensuite un langage de requêtes qui permet de modéliser une large classe de questions sur le fonctionnement issues de l'interaction en langue naturelle. Nous proposons des algorithmes de réponse qui permettent de traiter ces requêtes ainsi qu'un cadre formel pour prendre en compte des notions de bon sens dans les requêtes. Nous étudions ensuite le problème de la construction de réponses portant sur l'exécution passée du composant. Nous montrons qu'il est nécessaire d'utiliser une approche dynamique pour extraire des régularités dans les actions du composant et mettre en évidence des comportements, individuels dans le cas d'une interaction avec l'utilisateur ou collectifs dans le cas d'une interaction dans un système multi-agents. Nous montrons que nos travaux peuvent s'intégrer dans le cadre du web sémantique pour définir des composants actifs sous la forme de pages web dynamiques munies de capacité de raisonnement et d'interaction avec les utilisateurs ordinaires. Nous présentons enfin l'implémentation de notre modèle réalisée dans le projet InterViews et nous donnons des exemples de programmation et d'exécution de ces composants actifsIn this PhD thesis, we deal with a problem that is emerging in human-computer interaction. Our aim is to answer formal requests modelling common-sense questions that a human user can ask about an active software component's functioning. Current research in reasoning about actions propose to work with a logic model of the system and to answer only to well formed requests which cannot take into account common-sense notions that are used by human users in their questions about actions. Moreover, we want to be able to work directly with the component's code to answer such questions. We first present a programming language and a runtime model for active components that allows us to have access, at any time of the execution, to the description of the component's actions and physical status. We then present a request model that can be used to represent a wide class of questions about actions. We propose answering algorithms for use on these formal requests. We show that it is possible to take into account common-sense notions in these requests and we propose a formal frame for processing such "common-sense requests" about actions. Then, we study the issue of answering requests about the component's past execution. We show that using a dynamic approach is both possible and required, so as to extract regularities from the component's runtime. We show how this exhibits component behaviors that are required for the production of an explanation. We present an extension of this approach for extracting collective behaviors in multi-agent systems. We show that our work can be used within the semantic web in order to define active components as dynamic page web, provided with reasoning capabilities and capable of interacting with ordinary users in need for help. Finally, we present the implementation of our model within the InterViews project. We give both programming and execution examples of active components in this implementation
42
Seon, Guillaume. "Finite element-based failure models for carbon/epoxy tape composites." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28117.
43
Djenidi, Hicham. "Architectures logicielles dynamiques dédiées aux applications multimodales." Versailles-St Quentin en Yvelines, 2007. http://www.theses.fr/2007VERS0030.
Анотація:
L’objectif principal de nos travaux de recherche est double. En premier lieu, nous proposons une architecture logicielle (AL) nouvelle qui rassemble les propriétés récurrentes implicitement employées dans les dialogues multimodaux. Cette AL est modélisée, spécifiée formellement et raffinée par l’emploi de réseaux de Pétri colorés temporisés stochastiques (RPCTS). Elle réalise un moteur de fusion-fission multimodal. En second lieu, nous fournissons une méthodologie basée sur le concept de scénarios permettant la reconfiguration architecturale du moteur multimodal tout en garantissant un profil de qualités choisi. Ces deux propositions constituent une méthodologie qui a pour finalité un comportement intelligent de ce type d’application. L’architecture proposée est multiagent et ‘reconfigurable’ dynamiquement grâce à la modélisation par RPCTS. La méthodologie proposée est validée par le développement de prototypesThe main objective of this thesis is twofold. First, we propose new architectural paradigms for analyzing and extracting the collective and recurrent properties implicitly used in multimodal dialogs. These paradigms use the agent architecture concept to achieve their functionalities and unify them into software architecture modeled, specified and refined by stochastic timed colored Petri nets. Second, we propose a new methodology to show the ways in which agents can be introduced at the architectural level and how such agents improve some quality attributes by adapting dynamically the initial architecture via multimodal
44
Humphreys, Matthew. "Development and structural investigation of monocoque fibre composite trusses." Thesis, Queensland University of Technology, 2003. https://eprints.qut.edu.au/15898/1/Matthew_Humphreys_Thesis.pdf.
Анотація:
Fibre composite materials are gaining recognition in civil engineering applications as a viable alternative to traditional materials. Their migration from customary automotive, marine, aerospace and military industries into civil engineering has continued to gain momentum over the last three decades as new civil engineering applications develop. The use of fibre composite materials in civil engineering has now evolved from non-structural applications, such as handrails and cladding, into primary structural applications such as building frames, bridge decks and concrete reinforcement. However, there are issues which are slowing the use of fibre composite materials into civil engineering. Issues include high costs, difficulties in realising potential benefits, general lack of civil engineers' familiarity with the material and relatively little standardisation in the composites industry. For composites to truly offer a viable alternative to traditional construction materials in the civil engineering marketplace, it is essential that these issues be addressed. It is proposed that this situation could be improved by demonstrating that potential benefits offered by composites can be achieved with familiar civil engineering forms. These forms must be well suited to fibre composite materials and be able to produce safe and predictable civil engineering structures with existing structural engineering methods. Of the numerous structural forms currently being investigated for civil engineering applications, the truss form appears particularly well suited to fibre composites. The truss is a familiar structural engineering form which possesses certain characteristics that make it well suited to fibre composite materials. In this research a novel monocoque fibre composite truss concept was developed into a working structure and investigated using analytical and experimental methods. To the best of the author's knowledge the research presented in this thesis represents the first doctoral research into a structure of this type. This thesis therefore presents the details of the development of the monocoque fibre composite (MFC) truss concept into a working structure. The developed MFC truss was used as the basis for a detailed investigation of the structural behaviour of the MFC truss elements and the truss as a whole. The static structural behaviour of the principal MFC truss elements (tension members, compression members and joints) was investigated experimentally and analytically. Physical testing required the design and fabrication of a number of novel test rigs. Well established engineering principles were used along with complex finite element models to predict the behaviour of the tested truss elements and trusses. Results of the theoretical analysis were compared with experimental results to determine how accurately their static structural behaviour could be predicted. It was found that the static structural behaviour of all three principal truss elements could be accurately predicted with existing engineering methods and finite element analysis. The knowledge gained from the investigation of the principal truss elements was then used in an investigation of the structural behaviour of the MFC truss. Three full-scale MFC trusses were fabricated in the form of conventional Pratt, Howe and Warren trusses and tested to destruction. The investigation included detailed finite element modelling of the full-scale trusses and the results were compared to the full-scale test results. Results of the investigation demonstrated that the familiar Pratt, Howe and Warren truss forms could be successfully manufactured with locally available fibre composite materials and existing manufacturing technology. The static structural behaviour of these fibre composite truss forms was accurately predicted with well established engineering principles and finite element analysis. A successful marriage between fibre composite materials and a civil engineering structure has been achieved. Monocoque fibre composite trusses have been developed in the familiar Pratt, Howe and Warren truss forms. These structures possess characteristics that make them well suited to applications as primary load bearing structures.
45
Humphreys, Matthew. "Development and Structural Investigation of Monocoque Fibre Composite Trusses." Queensland University of Technology, 2003. http://eprints.qut.edu.au/15898/.
Анотація:
Fibre composite materials are gaining recognition in civil engineering applications as a viable alternative to traditional materials. Their migration from customary automotive, marine, aerospace and military industries into civil engineering has continued to gain momentum over the last three decades as new civil engineering applications develop. The use of fibre composite materials in civil engineering has now evolved from non-structural applications, such as handrails and cladding, into primary structural applications such as building frames, bridge decks and concrete reinforcement. However, there are issues which are slowing the use of fibre composite materials into civil engineering. Issues include high costs, difficulties in realising potential benefits, general lack of civil engineers' familiarity with the material and relatively little standardisation in the composites industry. For composites to truly offer a viable alternative to traditional construction materials in the civil engineering marketplace, it is essential that these issues be addressed. It is proposed that this situation could be improved by demonstrating that potential benefits offered by composites can be achieved with familiar civil engineering forms. These forms must be well suited to fibre composite materials and be able to produce safe and predictable civil engineering structures with existing structural engineering methods. Of the numerous structural forms currently being investigated for civil engineering applications, the truss form appears particularly well suited to fibre composites. The truss is a familiar structural engineering form which possesses certain characteristics that make it well suited to fibre composite materials. In this research a novel monocoque fibre composite truss concept was developed into a working structure and investigated using analytical and experimental methods. To the best of the author's knowledge the research presented in this thesis represents the first doctoral research into a structure of this type. This thesis therefore presents the details of the development of the monocoque fibre composite (MFC) truss concept into a working structure. The developed MFC truss was used as the basis for a detailed investigation of the structural behaviour of the MFC truss elements and the truss as a whole. The static structural behaviour of the principal MFC truss elements (tension members, compression members and joints) was investigated experimentally and analytically. Physical testing required the design and fabrication of a number of novel test rigs. Well established engineering principles were used along with complex finite element models to predict the behaviour of the tested truss elements and trusses. Results of the theoretical analysis were compared with experimental results to determine how accurately their static structural behaviour could be predicted. It was found that the static structural behaviour of all three principal truss elements could be accurately predicted with existing engineering methods and finite element analysis. The knowledge gained from the investigation of the principal truss elements was then used in an investigation of the structural behaviour of the MFC truss. Three full-scale MFC trusses were fabricated in the form of conventional Pratt, Howe and Warren trusses and tested to destruction. The investigation included detailed finite element modelling of the full-scale trusses and the results were compared to the full-scale test results. Results of the investigation demonstrated that the familiar Pratt, Howe and Warren truss forms could be successfully manufactured with locally available fibre composite materials and existing manufacturing technology. The static structural behaviour of these fibre composite truss forms was accurately predicted with well established engineering principles and finite element analysis. A successful marriage between fibre composite materials and a civil engineering structure has been achieved. Monocoque fibre composite trusses have been developed in the familiar Pratt, Howe and Warren truss forms. These structures possess characteristics that make them well suited to applications as primary load bearing structures.
46
Magalhães, Junior Jairo Torres. "Aspectos vetoriais da lutzomyia longipalpis: resposta comportamental a compostos orgânicos voláteis e uso na avaliação de infectividade de cães naturalmente infectados por leishmania infantum." Escola de Medicina Veterinária e Zootecnia, 2015. http://repositorio.ufba.br/ri/handle/ri/19687.
Анотація:
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Fundação de Amparo a Pesquisa do Estado da Bahia (FAPESB)
Leishmaniose Visceral é uma zoonose causada pelo protozoário Leishmania infantum e transmitida pelo flebotomíneo Lutzomyia longipalpis. O controle da doença é bastante complexo, sendo que atualmente sugere-se a necessidade de redirecionamento nas medidas de controle, sobretudo no que se refere à identificação de cães verdadeiramente transmissores e à necessidade de um refinamento no controle vetorial. Neste trabalho foi avaliada a infectividade de cães naturalmente infectados com L. infantum para a L. longipalpis, bem como a capacidade atrativa de diferentes compostos orgânicos voláteis para o mesmo vetor. A partir de testes xenodiagnósticos, foi observado que cães com maior manifestação de sinais clínicos são mais infectivos ao vetor que cães com pouco ou nenhum sinal clínico, entretanto não houve diferença na taxa de transmissibilidade quando diferentes protocolos de xenodiagnóstico foram confrontados. Sendo que, para cães infectados com L. infantum e agrupados conforme a presença de anormalidades clínicas e patológicas, a taxa de infectividade nos flebotomíneos foi significativamente menor (p=0,0098) , quando estes se alimentaram de cães com doença moderada (0,01%), comparativamente aos cães com doença severa (38,2%).Demonstrou-se também que machos e fêmeas de L. longipalpis são atraídos por compostos aldeídos e alcanos (octanal, decanal e heptadecano) identificados no pelo canino e álcoois (heptanol, octanol, octenol e nonanol) encontrados em plantas. Esses compostos químicos podem ser utilizados como iscas em armadilhas para captura dos insetos ou ainda associados com inseticidas de efeito residual. Mais estudos são necessários sobre a biologia e comportamento da L. longipalpis e sua relação com cães infectados com L. infantum, buscando melhor entender essa interface e identificar novas alternativas de controle para a leishmaniose visceral.
Visceral leishmaniasis is a zoonosis caused by the protozoan Leishmania infantum and transmitted by the phlebotominae sand fly Lutzomyia longipalpis. The control of the disease is quite complex, being suggested presently the necessity to redirect the control measures, especially concerning the identification of dogs truly transmitters and the necessity of a refinement of the vector control. This work was evaluated the infectivity of dogs naturally infected with L. infantum to L. longipalpis as well as the attractive ability of different volatile organic compounds to same vector. It was observed, by xenodiagnosis, that dogs with higher manifestation of clinical signs are more infective to the vector that dogs with few or no clinical signs, however there was no difference in the transmission rate when different xenodiagnosis methodologies were compared. Therefore for dogs infected with L. infantum and grouped according to presence of clinical and pathological abnormalities in the infectivity rate sandflies was significantly lower (p = 0.0098), when these were fed dogs with moderate disease (0, 01%) compared to dogs with severe disease (38.2%). It was also demonstrated that males and females of L. longipalpis are attracted by aldehyde and alkane (octanal, decanal and heptadecane) compounds identified on the canine hair and alcohols found in plants (octenol, octanol, heptanol and nonanol). These chemical compounds can be used as bait in traps to capture insects and even be associated with insecticides with residual effect. More studies are necessary about the biology and behavior of L. longipalpis and its relationship to dogs infected with L. infantum, searching to better understand this interface and identify new alternatives to control visceral leishmaniasis.
47
Chen, Mei-Chien, and 陳美蒨. "Effects of home-bleaching on composite resin restorative materials." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/18579751479161919478.
Анотація:
碩士國立陽明大學
臨床牙醫學研究所
95
Tooth bleaching has become popular in the esthetic dentistry. Previous literatures found that home-bleaching might increase degradation of composite resins. However the mechanism is still unclear. Four composite resins were enrolled in the study, including two light-polymerized hybrid composites (3M Z100 and Filtek Z250), one microfilled composite (Filtek Z350), and one polyacid-modified composite (compomer, Dyract AP). Thirty standardized disc specimens (15 x 1 mm) of each material were made and stored in distilled water for 7 days, in which 5 specimens of each material was used to measure the water sorption and solubility. Twenty specimens were randomly divided into two groups, in which one group was immersed in 10% carbamide peroxide solution for 8 hours per day for 28 days, and the other group was stored in distilled water as control. Surface properties, including Knoop microhardness, roughness and CIELab values of each specimen was measured, before bleaching treatment and repeatedly at intervals of 7, 14, 21 and 28 days, respectively. The rest specimens were used for examination under SEM and Raman spectroscope in order to investigate the surface characteristics and polymeric structures. The results showed that Z350 had higher water sorption then Z100 and DAP, while Z250 had the least. The impacts of home-bleaching on composite resin degradation were also different. DAP had the greatest degradation with the most color changes and roughness increase compared with the control group, followed by Z100, while Z350 and Z250 had the least degradation subjected to bleaching treatment. Bleaching impacts on microhardness of composite resins were material dependant. Bleached DAP and Z100 were softer than the control group, whereas bleached Z350 and Z250 were harder. With the observation of the surface of specimens under SEM, all materials tested had more degradation profile after home-bleaching compared to the control group. The Raman spectrum revealed that home-bleaching treatment changed the chemical polymeric structures of the composite resins. The aliphatic C=C bond vibration (ω = 1638 cm-1) was reduced and carbonyl bond vibration (C-O, ω = 1200 ~ 1355 cm-1) was increased in hybrid and microfilled composite resins. This denoted that oxidation reaction could be a possible mechanism of degradation of composite resins subjected to home-bleaching treatment. Meanwhile the CO2- asymmetric stretching vibration (ω = 1335 ~ 1440 cm-1) was reduced and carboxylic salts was increased in Raman spectrum of polyacid-modified composite resin. The possible reason is that home-bleaching accelerated the water diffusion and thus enhanced the acid-base neutralization of polyacid-modified composite resin. Within the limitation of this study, the degradation effects of home-bleaching on composite resins were material dependant, which might be related to the water diffusion of resin matrix, filler type and setting mechanism of these materials. SEM observation and Raman spectrum analyses seem to be good tools to evaluate the degradation of bleached composites, while microhardness of composite resins was not a good indicator. Applying the findings of this study, polyacid-modified composite resins should be avoided to restore the teeth before home-bleaching therapy, and also the discoloration and polymeric change of other composites should be anticipated, since home-bleaching could accelerate the degradation of composite resins and consequently increase the surface roughness, poor esthetics and tendency of wear.
48
YANG, SHENG-HU, and 楊勝湖. "Stress analysis of composite laminates with modulded-in hole." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/75683581399719081694.
49
Cai, Ming-Hong, and 蔡明宏. "Stress Distribution in Composite Plates with a Circular Hole." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/50053215901833466969.
Анотація:
碩士義守大學
土木與生態工程學系
102
The effect of various offaxis angles and lamina material properties on the stress distribution of a circular cutout in an orthotropic composite plate under off-axis loading is presented. Based on the generalized Hooke’s law and the complex variable method, a dimensionless analysis is used to evaluate the influence of various elastic moduli E1, E2, G12 and ν12 on the stress distribution along the boundary of the circular cutout under various off-axis loadings. The results obtained from this dimensionless analysis provide a set of general design guidelines for structural laminates with high precision requirements in the engineering applications.
50
Lai, Wen-You, and 賴玟佑. "The Study of Open Hole and Pin Hole Tensile Properties of Self-reinforced PET Composites." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/96et73.
Анотація:
碩士國立臺灣科技大學
材料科學與工程系
104
The tensile and bearing strength of notched composites is an important factor for composite structural design. However, no literature is available on the notch sensitivity and pin loaded effects of self-reinforced polymer composites. In this study, self-reinforced recycled poly (ethylene terephthalate) (srrPET) composites were produced by film stacking from fabrics composed of double covered uncommingled yarns (DCUYs). Composites specimens were subjected to uniaxial tensile, flexural and Izod impact tests and the related results compared with earlier ones achieved on srPET composites reinforced with non-recycled technical PET fibers. Further on, the effects of open circular holes on the tensile strength of srrPETs with various width-to-hole diameter (W/D) ratios of the specimens, the effects of pin-loaded tensile behavior of srrPET composites with various W/D ratios and edge distance-to-hole diameter (E/D) ratios of the specimens, the endurance limit of tension–tension fatigue of pin loaded composites and damage development in srrPETs assessed by located acoustic emission were studied. Damage development in srrPET composites indicates that srrPET composites have higher resistance of the composite to crack propagation. These results proved that srrPET composites is tough, ductile notch-insensitive materials and have superior load carrying capability. The experimental results indicate that the bilinear (yielding followed by post-yield hardening) stress-strain curves were recorded in the open hole tensile (OHT) measurements. The srrPET composites had extremely high yield strength retention (up to 142%) and high breaking strength retention (up to 81%) due to the superior ductile nature of the srrPET composites, which induces plastic yielding near the hole thereby reducing the stress concentration effect. The superior load carrying capability is found in srrPET composites and highly dependent on the W/D ratios. The bearing failure mode occurs in W/D>4, the composites has high yield bearing strength (99.4 MPa) and extremely high ultimate bearing strength (199.3 MPa) due to strong interfacial bonding between the fiber and matrix contributes higher bearing strength. The strong interfacial bonding in srrPET composites has higher fatigue cycles and shows good endurance ability.