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1

Goosen, Dominique. "Factors influencing fruit shape in lemons (Citrus limon L.)." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52842.

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Thesis (MScAgric)--University of Stellenbosch, 2002.
ENGLISH ABSTRACT: Lemons with an elongated fruit shape achieve premium prices in certain discerning markets. Factors influencing the fruit shape of lemons were investigated to fmd means to produce a crop with a higher percentage of elongated lemons. Intra-plant factors were investigated to understand the variation in fruit shape within a single tree and even within the same fruit cluster. Bearing position (leafy vs. leafless inflorescences) and position in the canopy (inside vs. outside) were taken into consideration, along with the number of seeds, number of segments and rind thickness in the center of the fruit as well as stem- and stylar-ends. Bearing position and position in the canopy had no effect on fruit shape, while the number of seeds was positively correlated with elongated lemons. Rootstocks were evaluated to determine the influence of rootstock type on fruit shape. Twelve rootstocks were evaluated in total, at Addo, Citrusdal and Nelspruit. At all three locations rootstock type had no or little influence on fruit shape. Different scions were also evaluated at both Addo and Citrusdal to determine whether a certain scion characteristically produces elongated fruit. A total of 20 different scions were evaluated, and as opposed to rootstocks, there were larger variations between scions. Of the commercially-produced scions, 'Fino' lemon had the least variation, producing elongated lemons more consistently than 'Lisbon' and 'Eureka' lemons. Of the other scions, 'Cicily' lemon produced fruit with the smallest L:D ratio, while 'Vema' lemon was the scion producing fruit with the largest L:D ratio. 'Vema' lemon is, however, not an attractive fruit, having a thick rough rind. In the case of grapefruit, unwanted "sheepnosed" fruit with thick rinds are common in areas with a low winter temperature at night. 'Eureka' lemon fruit from six different climatic areas were compared to evaluate the difference in fruit shape. Cooler areas, such as Vaalharts, had more elongated fruit than areas with a higher winter temperature, such as Nelspruit. Altering lemon fruit shape was also attempted by chemical manipulation, usmg gibberellin, cytokinin or auxin containing products. Promalin® (GA4+7, BA), Accet" (GA4+7, BA), Corasil E® (2,4-D), Provide® (GA4+7) and ProGibb® (GA)) were sprayed at different times and different concentrations. Promalin'" was partly successful in altering fruit shape, but these changes were not large enough from a commercial point of view. Promalin'" also resulted in a lower percentage fruit set. Accel'", Corasil E®, Provide® and ProGibb® were not successful in altering fruit shape favorably, with Corasil E® having a strong thinning effect.
AFRIKAANSE OPSOMMING: Fakore wat die verlenging van suurlemoene beïnvloed Suurlemoene met 'n verlengde vrugvorm behaal hoë pryse in sekere markete. Faktore wat die vrugvorm van suurlemoene beïnvloed is bestudeer om praktyke te vind wat die produksie van verlengde suurlemoene kan verhoog. Intra-plant faktore is bestudeer om die variasie in vrugvorm binne 'n enkele boom en ook in dieselfde vrugtros te verstaan. Dra-posisie ("wit" en "groen" blomme) asook posisie in die boom (binnevrugte vs. buitevrugte ) is in aanmerking geneem. Die invloed van die hoeveelheid sade en segmente per vrug, asook skil dikte in die middle van die vrug en aan stingel- en kelkkant is ook bestudeer. Dra-posisie en posisie van vrug in die boom, het geen invloed op vrugvorm gehad nie, terwyl die hoeveelheid sade per vrug die beste met vrugvorm gekorreleer was. Die invloed van onderstam tipe op vrugvorm is ook geëvalueer. Vrugvorm van twaalf onderdstamme in totaal is te Addo, Citrusdal en Nelspruit ondersoek. By al drie areas is klein verskille in vrugvorm van verskillende onderstamme opgemerk. Saam met die onderstamme is 20 seleksies te Addo en Citrusdalondersoek, om te bepaal of 'n sekere seleksie 'n karakteristieke verlengde vrugvorm openbaar. In teenstelling met onderstamme, is groter variasie tussen seleksies gevind. Vandie kommersiële kultivars, het 'Fino' suurlemoen die minste variasie openbaar en deurgans verlende vrugte gelewer, terwyl 'Lisbon' en 'Eureka' suurlemoene groter variasie gehad het. Vandie ander seleksies, het 'Cicily' suurlemoen geneig om vrugte met die kleinsteL:D verhouding te lewer, terwyl'Vema' suurlemoen deurgans vrugte met 'n groter L:D verhouding gelewer het. 'Vema' suurlemoen is egter nie 'n aantreklike vrug nie, aangesien dit 'n dik skil het. In die geval van pommelos word ongewenste vrugte met 'n "skaapneus" vorm algemeen aangetref in areas met 'n lae mininmum winter temperatuur. Vrugvorm van 'Eureka' suurlemoene van ses verskillende klimaats areas is vergelyk. Koeler areas, soos Vaalharts, het meer verlengde vrugte gehad, terwyl Nelspruit met 'n hoër winter temperatuur, ronder vrugte produseer het. Daar is ook gepoog om suurlemoen vrugvorm te manipuleer d.m.v. chemiese bespuitings. Ouksiene, gibbereliene en sitokiniene asook kombinasies daarvan, is gebruik. Promalin® (GA4+7, BA), Accel® (GA4+7,BA), Corasil E® (2,4-D), Provide® (GA4+7) en ProGibb® (GA3) is by verskillende tye en verskillende konsentrasies gespuit. Promalin® was gedeeltelik suksesvol in verlenging van vrugte, maar die veranderinge was te klein uit 'n kommersiële oogpunt. Promalin® het ook tot uitdunning van vrugte gelei. Accel", Corasil E®, Provide® en ProGibb® was nie suksesvol in verandering van suurlemoen vrugvorm nie. Corasil E®het tot strawwe vruguitdunning gelei.
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2

Jirasek, Catherine Alena. "A biomechanical model of branch shape in plants expressed using L-systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0017/MQ55218.pdf.

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3

Pant, Nishtha. "Synthesis and Characterization of L-Valine based Poly(ester urea)s for Shape Memory Applications." University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1607002293338635.

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4

Bragazzi, Lorenzo. "I materiali a memoria di forma: caratterizzazione e applicazione nel mondo dell'automazione." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10937/.

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Анотація:
L'obiettivo di questo lavoro di tesi è stato studiare le caratteristiche, le proprietà, le applicazioni con conseguenti vantaggi e svantaggi di un particolare tipo di smart materials: i materiali a memoria di forma. Il capitolo 1 tratterà delle leghe metalliche a memoria di forma, il successivo si concentrerà invece sui polimeri a memoria di forma. In ognuno di questi, relativamente al materiale affrontato, si presterà particolare attenzione agli “effetti” che contraddistinguono tali materiali da quelli più comuni, come l’effetto memoria di forma o la superelasticità. Successivamente, nei vari sottoparagrafi, l’attenzione si sposterà sulle tecniche di caratterizzazione, utili per capire le proprietà di una lega o di un polimero rispetto ad un altro, e sulle conseguenti classificazioni di entrambi. Per quanto riguarda i polimeri, si accenneranno certi parametri fondamentali di cui è necessario tener conto per conoscere bene il polimero considerato. La trattazione, in ambedue i casi, terminerà con un focus sulle applicazioni più diffuse e su quelle più interessanti di tali materiali, fornendo dettagli sulle tecnologie utilizzate e sugli stimoli dettati per eccitare i sistemi.
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5

López, Girona Elena. "Genetic architecture of agronomic traits in peach [Prunus persica (L.) Batsch]: subacid, flat shape and nectarine." Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/285555.

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Анотація:
L'objectiu dels programes de millora genètica del préssec és generar varietats adaptats a les condicions agronòmiques locals i satisfer els requeriments del consumidor. Això últim implica millorar la qualitat del fruit. L'estratègia seguida per molts milloradors es basa en la selección de descendents de creuaments on s’espera segregació per a caràcters fenotípics. Es tracta d’un mètode costós tant en temps com en diners a causa del período de juvenilitad del presseguer (2-3 anys) i també als recursos que suposa el mantener les plàntules en el camp durant el procés d’avaluació i selecció. L'objectiu d'aquesta tesi va ser el desenvolupament de marcadors moleculars per a la seva aplicació en la selecció assistida per marcadors (SAM) de tres caràcters del fruit: baixa acidesa, fruit pla i pell glabra. En els dos primers capítols estudiem el locus del carácter subàcido (D) i el fruit pla (S) i hem realitzat l’anàlisis d’associació en les seves respectives regions genòmiques. Per a ambdós caràcters s'han generat i validat marcadors moleculars (SSRs i SNPs) que poden ser directament aplicats a SAM. L'estudi de l’haplotipus subàcid ens va permetre identificar diversos gens candidats. Aquestes resultats ens suggereix l'existència d'un únic origen de l’al·lel subàcido. L'anàlisi del locus S ens va permetre identificar dues INDELs altament associats amb el fruit pla. Aquests polimorfismes es van observar en regió codificant del gen ppa025511m, concretament en el segon exò del gen. Aquesta associació va ser avaluada en un ampli panell de varietats i en una població obtinguda a partir del creuament de dues parentals de fruits plans. L'anàlisi de la seqüència completa d'aquest gen va permetre la identificació de la supressió d'un fragment de 9Kb que afecta la regió 5’UTR del gen així com al primer exò, a l’intró i a una petita part del segon exò. La funció d'aquest gen va ser validada en un mutant tipus “sport” generat espontàneament en un arbre de la varietat plana ‘UFO4’. Es tracta d'un mutante quimèric mb una mutació que només afecta a les cèl·lules de la segona capa meristemàtica (LII), que genera la polpa del fruit. L'amplificació per PCR de l’INDEL d'aquest gen en la polpa del mutant rodó va revelar un canvi a l’al·lel pla. Malgrat que l‘alelo pla és dominant, els fruits plans han de presentar-lo en hetericigosis per a ser viables. Aquest fet amb la reversió a la forma rodona del mutant d’UFO4 suggereixen que aquest al·lel pot actuar com dominant negatiu. En el tercer capítol seqüenciem el genoma de 5 varietats de préssec i els seus respectius mutantes nectarina. Es van a estimar la variabilitat somática i la mutació causal de la pell glabra. La metodología empleada per al processament de les lectures i la identificació dels petis polimorfismes va generar un excés de falsos polimorfismes, possiblement causats per alineaments erronis de les seqüències repetitives del genoma. Mitjançant l'ús d'un filtrat més restrictiu es va reduir aquest valor. Els valors de diversitat nucleotídica i d’heterozigositat van ser similars als observats per Aranzana et al., (2012) i Verd et al., (2013). L’analisi del locus G va mostrar una menor π i una major Ho. Sota dues possibles hipótesis per a l’estudi l’al·lel causal del caràcter nectarina vam identificar diversos gens candidats amb funcions relacionades amb el desenvolupament de la paret cel·lular. No obstant això cap d'ells va resultar ser PpeMYB25 on recentment s’ha descrit una inserció de 7Kb asssociada al carácter nectarina (Vendramin et al., 2014). La insuficient cobertura de seqüenciació en la regió genómica del locus G pot haver estat la causa de la no identificació d’aquest polimorfisme en les nostres seqüències.
The aim of current breeding programs is to provide new fruit varieties adapted to the local agronomic conditions and to satisfy the requirements of the consumers. This last fact implies to improve the fruit quality. The strategy followed by most breeding programs is based on performing controlled crosses to select those individuals showing the target traits. Although this approach has succeed in the production of most of the varieties available today, it is time consuming and costly due the time required to obtain fruits (2-3 years) and the resources needed to keep the seedlings in the field during the evaluation and selection processes. The objective of this thesis was to develop molecular markers useful in marker assisted selection (MAS) for three important agronomical traits in peach fruits: low acidity, flat shape and glabrous skin (nectarine trait). In the first two chapters of this document we have used region-based association analysis to study the architecture of the locus responsible for either sub-acid (D) and flat fruits (S). In both cases the study has provided markers (SSR and SNPs) ready to be applied for MAS in peach breeding programs. The study of the length of the sub-acid haplotype, which is maintained more than 24Kbp long, allowed to hypothesize about a unique origin of this trait and to identify candidate genes. Similarly, the analysis of the S locus allowed the identification of two linked INDELs in the second exon of the gene ppa025511m highly associated with the flat shape of the fruit. The association was tested in a broad panel of varieties and in the offspring of a crossing population between two flat peaches. The sequencing analysis of the whole gene allowed the identification of a big deletion, of about 9Kbp, affecting its 5’ UTR, its first exon and its intron. The function of the gene was validated in a round sport mutant from a flat peach (UFO-4). This mutant was chimeric; the mutation only affected cells of the second layer (LII) of the meristerm, which generates the flesh of the fruit. A PCR amplification of the gene and the use of specific primers for the INDEL revealed a mutation in the flat allele in the flesh of the chimeric mutant, which produced the reversion to the round shape. The obligated heterozygosis of the flat allele and the reversion to the wild shape suggest a dominant negative (DN) mechanism. In the third chapter we sequenced the whole genome of 5 peach varieties and 6 sport nectarines derived from them. We estimated the overall somatic variability and studied the causal mutation from hairy fruit to glabrous. The reads processing and SNP calling revealed an excess of false variants that was especially evident in the analysis of the sport mutants. One of the main causes for the false variants was the misalignments of repetitive regions. The use of more restrictive SNP calling filters reduced the excess of false variants. The nucleotide diversity and heterozygosity of the varieties was similar to the one reported for peach (Aranzana et al., 2012; Verde et al., 2013). The analysis of the variations in the G locus region showed lower and higher Ho. To look for the causal allele for the nectarine trait we postulated two possible causes for the new mutation. These data provided several candidate genes involved in the cell wall development, however none of them was the gene PpeMYB25, where a big insertion of 7Kb in its second exon has recently been described as linked with the trait (Vendramin et al., 2014). This was probably due to an insufficient sequencing coverage in this genomic region.
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6

Chari, Visesh. "Shape estimation of specular objects from multiview images." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENM106/document.

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Анотація:
Un des modèles les plus simples de surface de réfraction est une surface plane. Bien que sa présence soit omniprésente dans notre monde sous la forme de vitres transparentes, de fenêtres, ou la surface d'eau stagnante, très peu de choses sont connues sur la géométrie multi-vues causée par la réfraction d'une telle surface. Dans la première partie de cette thèse, nous analysons la géométrie à vues multiple d'une surface réfractive. Nous considérons le cas où une ou plusieurs caméras dans un milieu (p. ex. l'air) regardent une scène dans un autre milieu (p. ex. l'eau), avec une interface plane entre ces deux milieux. Le cas d'une photo sous-marine, par exemple, correspond à cette description. Comme le modèle de projection perspectif ne correspond pas à ce scenario, nous dérivons le modèle de caméra et sa matrice de projection associée. Nous montrons que les lignes 3D de la scène correspondent à des courbes quartiques dans les images. Un point intéressant à noter à propos de cette configuration est que si l'on considère un indice de réfraction homogène, alors il existe une courbe unique dans l'image pour chaque ligne 3D du monde. Nous décrivons et développons ensuite des éléments de géométrie multi-vues telles que les matrices fondamentales ou d'homographies liées à la scène, et donnons des éléments pour l'estimation de pose des caméras à partir de plusieurs points de vue. Nous montrons également que lorsque le milieu est plus dense, la ligne d'horizon correspond à une conique qui peut être décomposer afin d'en déduire les paramètres de l'interface. Ensuite, nous étendons notre approche en proposant des algorithmes pour estimer la géométrie de plusieurs surfaces planes refractives à partir d'une seule image. Un exemple typique d'un tel scenario est par exemple lorsque l'on regarde à travers un aquarium. Nous proposons une méthode simple pour calculer les normales de telles surfaces étant donné divers scenari, en limitant le système à une caméra axiale. Cela permet dans notre cas d'utiliser des approches basées sur ransac comme l'algorithme “8 points” pour le calcul de matrice fondamentale, d'une manière similaire à l'estimation de distortions axiales de la littérature en vision par ordinateur. Nous montrons également que le même modèle peut être directement adapté pour reconstruire des surfaces réflectives sous l'hypothèse que les surfaces soient planes par morceaux. Nous présentons des résultats de reconstruction 3D encourageants, et analysons leur précision. Alors que les deux approches précédentes se focalisent seulement sur la reconstruction d'une ou plusieurs surfaces planes réfractives en utilisant uniquement l'information géométrique, les surfaces spéculaires modifient également la manière dont l'énergie lumineuse à la surface est redistribuée. Le modèle sous-jacent correspondant peut être expliqué par les équations de Fresnel. En exploitant à la fois cette information géométrique et photométrique, nous proposons une méthode pour reconstruire la forme de surfaces spéculaires arbitraires. Nous montrons que notre approche implique un scenario d'acquisition simple. Tout d'abord, nous analysons plusieurs cas minimals pour la reconstruction de formes, et en déduisons une nouvelle contrainte qui combine la géométrie et la théorie de Fresnel à propos des surfaces transparentes. Ensuite, nous illustrons la nature complémentaire de ces attributs qui nous aident à obtenir une information supplémentaire sur l'objet, qu'il est difficile d'avoir autrement. Finalement, nous proposons une discussion sur les aspects pratiques de notre algorithme de reconstruction, et présentons des résultats sur des données difficiles et non triviales
The task of understanding, 3D reconstruction and analysis of the multiple view geometry related to transparent objects is one of the long standing challenging problems in computer vision. In this thesis, we look at novel approaches to analyze images of transparent surfaces to deduce their geometric and photometric properties. At first, we analyze the multiview geometry of the simple case of planar refraction. We show how the image of a 3D line is a quartic curve in an image, and thus derive the first imaging model that accounts for planar refraction. We use this approach to then derive other properties that involve multiple cameras, like fundamental and homography matrices. Finally, we propose approaches to estimate the refractive surface parameters and camera poses, given images. We then extend our approach to derive algorithms for recovering the geometry of multiple planar refractive surfaces from a single image. We propose a simple technique to compute the normal of such surfaces given in various scenarios, by equating our setup to an axial camera. We then show that the same model could be used to reconstruct reflective surfaces using a piecewise planar assumption. We show encouraging 3D reconstruction results, and analyse the accuracy of results obtained using this approach. We then focus our attention on using both geometric and photometric cues for reconstructing transparent 3D surfaces. We show that in the presence of known illumination, we can recover the shape of such objects from single or multiple views. The cornerstone of our approach are the Fresnel equations, and we both derive and analyze their use for 3D reconstruction. Finally, we show our approach could be used to produce high quality reconstructions, and discuss other potential future applications
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7

Fantoni, Sophia. "Realizzazione di un'interfaccia naturale basata su Leap Motion per un sistema CBIR." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19111/.

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Il progetto mira alla realizzazione di un'interfaccia naturale in grado di acquisire uno sketch. Le immagini saranno costruite tramite il movimento delle mani catturato dal dispositivo Leap Motion. L'immagine prodotta verrà salvata ed utilizzata per una ricerca di figure similari, presenti nel dataset. Per identificare e selezionare le immagini più simili sono state combinate le tecniche di feature di forma: shape matrix e local binary pattern.
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8

Mazzotti, Francesca. "Studio e sviluppo di un metodo per l'esclusione delle vene polmonari per la valutazione della volumetria atriale." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/12201/.

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La fibrillazione atriale (FA) è l'aritmia cardiaca sostenuta di più frequente riscontro nella pratica clinica, in quanto colpisce l'1-2% della popolazione generale. La terapia farmacologica rimane un fondamento nel trattamento dell'aritmia, ma negli ultimi anni nuove tecniche come l'ablazione transcatetere stanno diventando valide alternative, garantendo una migliore qualità di vita al paziente e una maggiore probabilità di mantenere ritmo sinusale. Uno dei problemi principali associati alla FA è l'insorgere di recidive a breve o lungo termine. Per evitare terapie inefficaci, prevenire le recidive e soprattutto ridurre gli eventi clinici legati all'aritmia, la ricerca si sta spingendo verso la valutazione di possibili fattori predittori di ricorrenza della FA, tra cui il volume dell'atrio sinistro. Una conseguenza molto frequente della FA è infatti la dilatazione dell'atrio sinistro, che può facilitare l'innesco dell'aritmia e determinarne la ricorrenza. Una corretta valutazione della volumetria atriale potrebbe quindi essere di grande aiuto al medico nella scelta delle migliori strategie da adottare per ciascun paziente e potrebbe anche essere predittivo di ricorrenza di FA in seguito ad ablazione. Il lavoro di tesi proposto si inserisce all'interno di un progetto più ampio volto allo sviluppo di un modello di atrio sinistro patient-specific al fine di fornire un'accurata guida anatomica in sede di ablazione e caratterizzare il volume atriale e la sua relazione con l'outcome della procedura. In particolare ci si è occupati dell'implementazione in ambiente Matlab di un algoritmo per l'esclusione delle vene polmonari da mesh 3D dell'atrio sinistro e della successiva chiusura della mesh per il calcolo del volume. L’algoritmo è stato testato su 26 pazienti: per la validazione del metodo, i dati ottenuti sono stati poi confrontati con un gold standard, rappresentato dal volume ottenuto dal tracciamento manuale del radiologo.
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9

Al-Dulaimi, Khamael Abbas Khudhair. "White blood cells classification using higher order spectra and l-moments invariant features." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/208261/1/Khamael%20Abbas%20Khudhair_Al-Dulaimi_Thesis.pdf.

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This project was a step forward in development of methods to investigate white blood cells and their types. The thesis investigated segmentation and classification methods for white blood cells and their nuclei from other components, such red blood cells, platelets and background, using signal processing, image processing and machine learning techniques, in order to generate automated reports. The outcome of the project was to enhance the accuracy of pathologists’ decisions and their efficiency, and overall benefit patients for faster and more accurate diagnosis of diseases under varying laboratory conditions in the future.
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10

Gaborit, Pierre. "Unification des modèles d’endommagement de type Lemaitre, pour la fatigue LCF/HCF, multiaxiale et aléatoire." Thesis, Cachan, Ecole normale supérieure, 2015. http://www.theses.fr/2015DENS0041.

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Les travaux présentés concernent le développement d'un modèle de prévision de durée de vie unifié pour traiter les problématiques de fatigue à faible et grand nombre de cycles. Le modèle est basé sur une approche à deux échelles et un endommagement de type Lemaitre. Le caractère "en vitesse" de la loi d'endommagement permet de traiter des chargements complexes, non proportionnels et aléatoires. Une campagne expérimentale de fatigue sur 12 éprouvettes cruciformes en alliage TA6V pour application aérospatiale est présentée. Elle comporte des essais biaxiaux proportionnels et non proportionnels ainsi que des cas de chargement pseudo-aléatoires. L'utilisation de la corrélation d'images numériques prises dans la zone utile permet d'évaluer les déformations locales en réponse aux sollicitations appliquées. Les cas de chargements sont simulés afin de confronter les déformations de surface et les durées de vie obtenues par calcul, aux résultats expérimentaux. Parmi les contributions théoriques présentées dans le manuscrit, sont à noter : - La proposition d'une nouvelle loi d'évolution pour écrouissage cinématique adaptée au comportement élastoplastique du TA6V sous chargement cyclique; - L'utilisation d'une correction élastoplastique locale permettant d'évaluer les déformations plastiques en surface à partir de calculs de structures linéaires; - L'amélioration d'un critère de micro-plasticité pour la prise en compte des effets de contrainte moyenne et de triaxialité en fatigue à grand nombre de cycles; - L'unification de deux lois d'endommagement afin d'étendre le domaine de validité du modèle initial vers les durées de vie à faible nombre de cycles. La démarche s'appuyant sur le cadre thermodynamique de la mécanique des milieux continus, de nombreuses perspectives d'amélioration du modèle sont discutées
This work presents the proposal of a unifying predictive model to deal with LCF and HCF problems. It is based on a two-scale approach initially developed by Lemaitre. As the damage evolution law is rate written, complexity due to non proportional and random loadings may also be treated. An experimental fatigue campaign of 12 cross shaped samples made of TA6V alloy for aerospace applications is presented. It includes not only proportional and non proportional biaxial tests but also pseudo random loadings. Digital Image Correlation is used to evaluate the local strains from pictures taken in the zone of interest. Loadings are the simulated and both strains and lifetimes are compared to experimental observations. Among the theoretical contributions presented in this work, the main are: - A new kinematic hardening evolution law for the modeling of elasto-plasticity of TA6V alloy under cyclic loadings; - Use of local elastoplastic correction from linear Finite Element Calculation to estimate plastic strains in the structure zone of interests; - Improvements of the micro-plastic yield function to take into account mean stress effect and triaxiality effects in the lifetime prediction in HCF domain; - A unifying method of two damage variables in order to extend the validity domain of the initial model to shorter lifetimes (LCF). As the model is based on a thermodunamical framework for continuum mechanics, several extension are mentioned as future propects
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11

Lin, Tian Ran. "Vibration of finite coupled structures, with applications to ship structures." University of Western Australia. School of Mechanical Engineering, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0093.

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[Truncated abstract] Shipbuilding is fast becoming a priority industry in Australia. With increasing demands to build fast vessels of lighter weight, shipbuilders are more concerned with noise and vibration problems in ships than ever. The objective of this thesis is to study the vibration response of coupled structures, in the hope that the study may shed some light in understanding the general features of ship vibration. An important feature characterizing the vibration in complex structures is the input mobility, as it describes the capacity of structures in accepting vibration energy from sources. The input mobilities of finite ribbed plate and plate/plate coupled structures are investigated analytically and experimentally in this study. It is shown that the input mobility of a finite ribbed plate is bounded by the input mobilities of the uncoupled plate and beam(s) that form the ribbed plate and is dependent upon the distance between the source location and the stiffened beam(s). Off-neutral axis loading on the beam (point force applied on the beam but away from the beam’s neutral axis) affects the input power, kinetic energy distribution in the component plates of the ribbed plate and energy flow into the plates from the beam under direct excitation ... solutions were then used to examine the validity of statistical energy analysis (SEA) in the prediction of vibration response of an L-shaped plate due to deterministic force excitations. It was found that SEA can be utilized to predict the frequency averaged vibration response and energy flow of L-shaped plates under deterministic force (moment) excitations providing that the source location is more than a quarter of wavelength away from the plate edges. Furthermore, a simple experimental method was developed in this study to evaluate the frequency dependent stiffness and damping of rubber mounts by impact test. Finally, analytical methods developed in this study were applied in the prediction of vibration response of a ship structure. It was found that input mobilities of ship hull structures due to machinery excitations are governed by the stiffness of the supporting structure to which the engine is mounted. Their frequency averaged values can be estimated from those of the mounting structure of finite or infinite extents. It was also shown that wave propagation in ship hull structures at low frequencies could be attenuated by irregularities imposed to the periodic locations of the ship frames. The vibration at higher frequencies could be controlled by modifications of the supporting structure.
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12

Roozbehjavan, Pooneh. "Experimental and numerical study of distortion in flat, L-shaped, and U-shaped carbon fiber-epoxy composite parts." Thesis, Wichita State University, 2012. http://hdl.handle.net/10057/5539.

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In this work, the effect of different parameters, including stacking sequence, part thickness, and tooling material, on distortion of flat panels was investigated. A Romer arm equipped with a laser scanner was used to obtain the maximum amount of distortion as well as the 3D pattern of distortion for each panel. Among the different stacking sequences, the maximum distortion was observed in the asymmetric and balanced panel, while the least distortion belonged to the symmetric and unbalanced one. Furthermore, thinner panels were more distorted than thicker panels with the same planar size and stacking sequences. This study showed that distortion of the flat panels caused by asymmetry in the stacking sequence was an order of magnitude greater than distortion of the panels due to imbalance in the stacking sequence. L-shaped and U-shaped panels were also fabricated to investigate the effect of stacking sequence on spring-in angle and warpage of the panels. Among all the stacking sequences, the panel with an asymmetric and unbalanced stacking sequence showed the least spring-in angle, while the largest angle was observed in the symmetric and balanced panel. Although asymmetry in the stacking sequences reduced the spring-in angle, significantly more warpage was observed in the panels with asymmetric stacking sequences, as compared to the symmetric ones. MSC Marc was used to predict the distortion of the panels, and the simulation results were compared with the experimental results for several stacking sequences of the flat and the L-shaped panels. An L-shaped panel with the stacking sequence of [0/45/90/-45]4 was simulated to investigate the effect of curve radius and tool geometry on the spring-in angle. The FEA results showed that curing the L-shaped panel on a concave tool led to less spring-in angle, as compared to the panel confined to a convex tool.
Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering
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13

Adolfsson, Oscar. "Effekter av inkuberingstemperatur hos juvenil atlantlax (Salmo salar L.)." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-67269.

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Rising temperatures, because of climate change, will have major consequences for the world's fish populations, including the Atlantic salmon Salmo salar L. The greatest temperature changes are expected to occur during winter, which will affect S. salar since the eggs are developing during this time of year. Several studies have shown that elevated temperatures during embryogenesis cause morphological changes, in S. Salar, that are shown in later life stages. Some of these studies indicate that eggs incubated at high temperatures should generate parr with deeper bodies. To investigate whether high temperatures during the egg stage cause changes in body shape, parr from normal and high temperature incubated eggs, referred to as as “cold” and “warm” fish, respectively, were examined. A box-truss of euclidean distances between 10 landmarks on the fish body and a discriminant function analysis (DFA) was used to determine which of the distances best discriminated between the two groups. The test showed a significant discrimination between cold and warm parr regarding body shape where cold parr had greater heads and warm parr were deeper over the tail region and showed greater distances between the pelvic fin and the front attachment of the anal fin. 67,3 % of all parr where correctly classified by the test. These results support those notions that indicates that the incubation temperature is important for the morphological development of S. salar although it does not support the hypothesis.
Stigande temperaturer, till följd av klimatförändringar kommer att få stora konsekvenser för jordens fiskpopulationer, däribland atlantlaxen Salmo. Salar L. Störst temperaturförändringar väntas ske vintertid, vilket kommer att påverka S. Salar som övervintrar sin rom. Flera studier har visat att förhöjda temperaturer under embryogenesen ger upphov till morfologiska förändringar hos S. Salar under senare livsstadier. Några studier pekar mot att högtemperaturinkuberad rom torde ge upphov till parr med djupare kroppsform. För att undersöka om höga temperaturer under romstadiet ger upphov till förändringar beträffande kroppsform undersöktes parr (kalla resp. varma) från normal-  respektive högtemperaturinkuberad rom. Med hjälp av ett rutnät / box-truss mättes avstånd mellan 10 landmärken på fiskkroppen och en discriminant function analysis DFA användes för att avgöra vilket av avstånden som bäst diskriminerade mellan de båda grupperna. Testet visade en signifikant diskriminering mellan kalla och varma parr beträffande kroppsform där kalla parr hade större huvudmått och varma parr hade djupare mått över stjärtspolen och längre mått mellan analfenans främre infästning och bukfenan.  67,3 % av all parr förutspåddes tillhöra rätt grupp. Dessa resultat är i linje med den litteratur som anger att inkuberingstemperaturen har betydelse för den morfologiska utvecklingen hos S. Salar däremot stödjer de inte den angivna hypotesen.
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14

Azem, Leila. "Analyse des liens entre un modèle d'endommagement et un modèle de fracture." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLX006/document.

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Cette thèse est consacrée à la dérivation des modèles de fracture comme limite de modèles d'endommagement.L'étude est justifiée essentiellement à travers des simulations numériques.On s'intéresse à étudier un modèle d'endommagement initié par Allaire, Jouve et Vangoethem.Nous apportons des améliorations significatives à ce modèle justifiant la cohérence physique de cette approche.D'abord, on ajoute une contrainte sur l'épaisseur minimale de la zone endommagée, puis on ajoute la condition d'irréversibilité forte.Nous considérons en outre un modèle de fracture avec pénalisation de saut obtenu comme limite asymptotique d'un modèle d'endommagement.Nous justifions ce modèle par une étude numérique et asymptotique formelle unidimensionnelle.Ensuite, la généralisation dans le cas 2D est illustrée par des exemples numériques
This thesis is devoted to the derivation of fracture models as limit damage models.The study is justified mainly through numerical simulations.We are interested in studying a damage model initiated by Allaire, Jouve and Vangoethem.We are making significant improvements to this model justifying the physical consistency of the approach.First, we add a constraint on the minimum thickness of the damaged area and then we add a condition of strong irreversibility.We see also a fracture model with jump penalization obtained as an asymptotic limit of a damage model.We justify this model by a one-dimensional formal asymptotic numerical study.Then, the generalization in the case 2D is illustrated by numerical examples
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15

Giguelay, Jade. "Estimation des moindres carrés d'une densité discrète sous contrainte de k-monotonie et bornes de risque. Application à l'estimation du nombre d'espèces dans une population." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS248/document.

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Cette thèse est une contribution au domaine de l'estimation non-paramétrique sous contrainte de forme. Les fonctions sont discrètes et la forme considérée, appelée k-monotonie, k désignant un entier supérieur à 2, est une généralisation de la convexité. L'entier k constitue un indicateur du degré de creux d'une fonction convexe. Le manuscrit est structuré en trois parties en plus de l'introduction, de la conclusion et d'une annexe.Introduction :L'introduction comprend trois chapitres. Le premier présente un état de l'art de l'estimation de densité sous contrainte de forme. Le second est une synthèse des résultats obtenus au cours de la thèse, disponible en français et en anglais. Enfin, le Chapitre 3 regroupe quelques notations et des résultats mathématiques utilisés au cours du manuscrit.Partie I : Estimation d'une densité discrète sous contrainte de k-monotonieDeux estimateurs des moindres carrés d'une distribution discrète p* sous contrainte de k-monotonie sont proposés. Leur caractérisation est basée sur la décomposition en base de spline des suites k-monotones, et sur les propriétés de leurs primitives. Les propriétés statistiques de ces estimateurs sont étudiées. Leur qualité d'estimation, en particulier, est appréciée. Elle est mesurée en terme d'erreur quadratique, les deux estimateurs convergent à la vitesse paramétrique. Un algorithme dérivé de l'Algorithme de Réduction de Support est implémenté et disponible au R-package pkmon. Une étude sur jeux de données simulés illustre les propriétés de ces estimateurs. Ce travail a été publié dans Electronic Journal of Statistics (Giguelay, 2017).Partie II : Calculs de bornes de risqueDans le premier chapitre de la Partie II, le risque quadratique de l'estimateur des moindres carrés introduit précédemment est borné. Cette borne est adaptative en le sens qu'elle dépend d'un compromis entre la distance de p* à la frontière de l'ensemble des densités k-monotones à support fini, et de la complexité (en terme de décomposition dans la base de spline) des densités appartenant à cet ensemble qui sont suffisamment proches de p*. La méthode est basée sur une formulation variationnelle du risque proposée par Chatterjee (2014) etgénéralisée au cadre de l'estimation de densité. Par la suite, les entropies à crochet des espaces fonctionnels correspondants sont calculées afin de contrôler le supremum de processus empiriques impliqué dans l'erreur quadratique. L'optimalité de la borne de risque est ensuite discutée au regard des résultats obtenus dans le cas continu et dans le cadre de la régression.Dans le second chapitre de la Partie II, des résultats complémentaires sur les entropies à crochet pour les espaces de fonctions k-monotones sont donnés.Partie III : Estimation du nombre d'espèces dans une population et tests de k-monotonieLa dernière partie traite du problème de l'estimation du nombre d'espèces dans une population. La modélisation choisie est celle d'une distribution d'abondance commune à toutes les espèces et définie comme un mélange. La méthode proposée repose sur l'hypothèse de k-monotonie d'abondance. Cette hypothèse permet de rendre le problème de l'estimation du nombre d'espèces identifiable. Deux approches sont proposées. La première est basée sur l'estimateur des moindres carrés sous contrainte de k-monotonie, tandis que la seconde est basée sur l'estimateur empirique. Les deux estimateurs sont comparés sur une étude sur données simulées. L'estimation du nombre d'espèces étant fortement dépendante du degré de k-monotonie choisi dans le modèle, trois procédures de tests multiples sont ensuite proposées pour inférer le degré k directement sur la base des observations. Le niveau et la puissance de ces procédures sont calculés, puis évalués au moyen d'une étude sur jeux de données simulés et la méthode est appliquée sur des jeux de données réels issus de la littérature
This thesis belongs to the field of nonparametric density estimation under shape constraint. The densities are discrete and the form is k-monotonicity, k>1, which is a generalization of convexity. The integer k is an indicator for the hollow's degree of a convex function. This thesis is composed of three parts, an introduction, a conclusion and an appendix.Introduction :The introduction is structured in three chapters. First Chapter is a state of the art of the topic of density estimation under shape constraint. The second chapter of the introduction is a synthesis of the thesis, available in French and in English. Finally Chapter 3 is a short chapter which summarizes the notations and the classical mathematical results used in the manuscript.Part I : Estimation of a discrete distribution under k-monotonicityconstraintTwo least-square estimators of a discrete distribution p* under constraint of k-monotonicity are proposed. Their characterisation is based on the decomposition on a spline basis of k-monotone sequences, and on the properties of their primitives. Their statistical properties are studied, and in particular their quality of estimation is measured in terms of the quadratic error. They are proved to converge at the parametric rate. An algorithm derived from the support reduction algorithm is implemented in the R-package pkmon. A simulation study illustrates the properties of the estimators. This piece of works, which constitutes Part I of the manuscript, has been published in ElectronicJournal of Statistics (Giguelay, 2017).Part II : Calculation of risks boundsIn the first chapter of Part II, a methodology for calculating riskbounds of the least-square estimator is given. These bounds are adaptive in that they depend on a compromise between the distance of p* on the frontier of the set of k-monotone densities with finite support, and the complexity (linked to the spline decomposition) of densities belonging to this set that are closed to p*. The methodology based on the variational formula of the risk proposed by Chatterjee (2014) is generalized to the framework of discrete k-monotone densities. Then the bracketting entropies of the relevant functionnal space are calculating, leading to control the empirical process involved in the quadratic risk. Optimality of the risk bound is discussed in comparaison with the results previously obtained in the continuous case and for the gaussian regression framework. In the second chapter of Part II, several results concerningbracketting entropies of spaces of k-monotone sequences are presented.Part III : Estimating the number of species in a population and tests of k-monotonicityThe last part deals with the problem of estimating the number ofpresent species in a given area at a given time, based on theabundances of species that have been observed. A definition of ak-monotone abundance distribution is proposed. It allows to relatethe probability of observing zero species to the truncated abundancedistribution. Two approaches are proposed. The first one is based on the Least-Squares estimator under constraint of k-monotonicity, the second oneis based on the empirical distribution. Both estimators are comparedusing a simulation study. Because the estimator of the number ofspecies depends on the value of the degree of monotonicity k, we proposea procedure for choosing this parameter, based on nested testingprocedures. The asymptotic levels and power of the testing procedureare calculated, and the behaviour of the method in practical cases isassessed on the basis of a simulation study
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16

Hashtroodi, Seyedowjan. "Crack Propagation Analysis of a Pre-stressed L-shaped Spandrel Parking Garage Beam." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1420753991.

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17

Trincado, Guillermo. "Dynamic modeling of branches and knot formation in loblolly pine (Pinus taeda L.) trees." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/28157.

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A stochastic framework to simulate the process of initiation, diameter growth, death and self-pruning of branches in loblolly pine (Pinus taeda L.) trees was developed. A data set was obtained from a destructive sampling of whorl sections from 34 trees growing under different initial spacing. Data from dissected branches were used to develop a model for representing knot shape, which assumed that the live portion of a knot can be modeled by a one-parameter equation and the dead portion by assuming a cylindrical shape. For the developed knot model analytical expressions were derived for estimating the volume of knots (live/dead portions) for three types of branch conditions on simulated trees: (i) live branches, (ii) non-occluded dead branches, and (iii) occluded dead branches. This model was intended to recover information on knots shape and volume during the simulation process of branch dynamics. Three different components were modeled and hierarchically connected: whorl, branches and knots. For each new growing season, whorls and branches are assigned stochastically along and around the stem. Thereafter, branch diameter growth is predicted as function of relative location within the live crown and stem growth. Using a taper equation, the spatial location (X,Y,Z) of both live and dead portion of simulated knots is maintained in order to create a 3D representation of the internal stem structure. At the end of the projection period information on (i) vertical trend of branch diameter and location along and around the stem, (ii) volume of knots, and (iii) spatial location, size and type (live and dead) of knots can be obtained. The proposed branch model was linked to the individual-tree growth and yield model PTAEDA3.1 to evaluate the effect of initial spacing and thinning intensity on branch growth in sawtimber trees. The use of the dynamic branch model permitted generation of additional information on sawlog quality under different management regimes. The arithmetic mean diameter of the largest four branches, one from each radial quadrant of the log (i.e. Branch Index, BI) and the number of whorls per log were considered as indicators of sawlog quality. The developed framework makes it possible to include additional wood properties in the simulation system, allowing linkage with industrial conversion processes (e.g. sawing simulation). This integrated modeling system should promote further research to obtain necessary data on crown and branch dynamics to validate the overall performance of the proposed branch model and to improve its components.
Ph. D.
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18

Kůdela, Jakub. "Stochastická optimalizace v programu AIMMS." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231064.

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Tato diplomová práce uvádí základní poznatky matematického a především stochastického programování. Navíc se zabývá použitím softwaru AIMMS při vytváření a řešení optimalizačních problémů. Naším hlavním cílem je naprogramovat v softwaru AIMMS několik metod řešení problémů stochastického programování a ukázat jejich použití a užitečnost na vybraných problémech. Jedním z problémů, který jsme si zvolili, je model spalovny. Všechny AIMMS programy, které v našem textu použijeme a popíšeme, a jejich zdrojové kódy budou přiloženy v dodatcích.
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19

Smolen, Justin Alexander. "Emulsion Electrospinning for Producing Dome-Shaped Structures Within L-Tyrosine Polyurethane Scaffolds for Gene Delivery." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1291323933.

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20

Andrade, Cássio Bento de. "Análise da antena planar de F-invertido pelo método das diferenças finitas no domínio do tempo." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/36012.

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Neste trabalho é apresentada uma análise da antena planar F-invertido (PIFA) com o objetivo de identificar os parâmetros geométricos que influenciam nas características de desempenho: frequência de ressonância, perda de retorno e largura de banda. Para realizar este estudo é desenvolvido um algoritmo em linguagem C baseado no método das Diferenças Finitas no Domínio do Tempo (FDTD). Duas PIFAs de geometria distintas foram investigadas. O primeiro modelo trata da geometria tradicional de elemento irradiador e plano de terra, ambos retangulares. Já o segundo modelo apresenta a fenda em formato de L no elemento irradiador, para operação em frequência dupla, e o plano de terra em formato de T, visando a aumentar a largura de banda. Os resultados da simulação do algoritmo identificam os parâmetros que influenciam no aumento nas duas larguras de banda, e são aplicados na prototipação de uma PIFA GSM-900 e GSM-1800. As medidas de laboratório do protótipo evidenciam os resultados previstos pelo algoritmo.
A Planar Inverted-F Antenna (PIFA) analysis is presented in this work, aiming to identify the geometric parameters that influence the antenna performance, such as resonant frequency, return loss and bandwidth. To accomplish this goal, an algorithm in C language based on the Finite-Difference Time-Domain (FDTD) method is developed. Two PIFAs with distinct geometries are investigated. The first one corresponds to a typicall rectangular patch and ground plane, The second model presents an L-shaped slot for dual frequency band operation, combined with a T-shaped ground plane, in order to increase the bandwidth. The simulated results obtained by algorithm identify the parameters that respond for both bandwidths enhancement, and are applied in a PIFA GSM-900/GSM-1800 practical project. The prototype’s measurements confirm the simulated results.
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21

Sartori, Cédric. "Modélisation de l'endommagement dynamique avec prise en compte de l'effet de forme des cavités." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0195.

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Анотація:
L'endommagement des matériaux ductiles est un processus impliquant trois étapes : la nucléation, la croissance et la coalescence de vides. La phase de croissance des vides a été largement étudiée dans la littérature. Il a été montré que, durant cette étape, la forme des vides joue un rôle fondamental sur le comportement macroscopique du matériau. Dans le cas de sollicitations dynamiques, les effets micro inertiels, qui résultent des accélérations subies par la matrice au voisinage du vide, influent eux aussi fortement sur la croissance des vides. Cependant, les travaux intégrant simultanément ces deux contributions (effets inertiels et forme) sont très rares. L'objectif de ce travail est de proposer un modèle de comportement pour les matériaux poreux qui prend en compte la forme des vides et les effets micro inertiels. Dans une première partie, un volume élémentaire représentatif défini par deux ellipsoïdes allongés confocaux est utilisé pour représenter le matériau poreux. La matrice est rigide viscoplastique. En se basant sur les travaux de Molinari et Mercier (2001), la contrainte macroscopique se décompose en une partie statique et une partie dynamique. La contrainte statique est décrite par le modèle de Gologanu et al. (1997). La contrainte dynamique est obtenue en adoptant le champ de vitesse de Gologanu et al. (1993). Avec cette modélisation, il est montré que la contrainte dynamique est liée de façon quadratique au tenseur des vitesses des déformations et de façon linéaire à sa dérivée par rapport au temps. Le modèle fait l'objet d'une validation sur la base de comparaisons avec des résultats de calculs par éléments finis. Différentes forme de vides et valeurs de la porosité ont été considérées. Dans une seconde partie, le cas de matériaux contenant des vides aplatis est abordé ; le volume élémentaire représentatif est défini par deux ellipsoïdes confocaux aplatis. La contrainte statique est toujours décrite par le modèle de Gologanu et al. (1997). La contrainte dynamique est obtenue en adoptant le champ de vitesse de Gologanu et al. (1994). La procédure de validation est identique à celle mise en œuvre dans le cas des vides allongés. Une bonne adéquation entre les résultats du modèle et les résultats de calculs par éléments finis est retrouvée. L'utilisation des surfaces d'écoulement permet de mettre en lumière les effets de la forme des vides sur le comportement du matériau poreux sous chargement dynamique. En fonction du chargement appliqué, certaines géométries de vide favorisent la déformation du matériau. Le cas particulier du vide sphérique est étudié comme limite des deux modèles. La continuité des deux modèles est démontrée. L'évolution de la porosité et de la forme des vides dans un matériau poreux sous chargement dynamique est analysée. Des comparaisons avec des résultats de simulations par éléments finis sont proposées. L'influence de la triaxialité et de la vitesse du chargement sur le comportement dynamique du matériau poreux est étudiée, ainsi que celle de la forme initiale du vide. Au final, il est démontré que le modèle développé dans cette thèse permet de retrouver les tendances fournies par les calculs éléments finis
The ductile fracture mechanism involves three stages: void nucleation, void growth and void coalescence. Under dynamic loading conditions, void growth is strongly affected by microinertia effects resulting from the local acceleration of the matrix material in the vicinity of the void. Several works devoted to quasi-static conditions also show that void shape has a strong impact on the behavior of porous ductile materials. However, there exist only few works considering the combined effect of these two contributions. In the present work, we propose an original, multi-scale constitutive model of porous materials, taking into account void shape and micro-inertia effects. In a first step, a representative volume element defined by two confocal prolate spheroids is used to represent the porous material. The matrix behavior is assumed to be rigid-viscoplastic. Based on the work of Molinari and Mercier (2001), the macroscopic stress is the sum of a static and a dynamic part. The static contribution is described by the Gologanu et al. model (1997). The dynamic stress is derived by choosing the trial velocity field proposed by Gologanu et al. (1993). With the present modeling, a link is established between the macroscopic dynamic stress, on the one hand and, the macroscopic strain rate tensor and its time derivative on the other hand. To validate the proposed model, finite element computations have been performed for different void geometries and void volume fractions. The influence of micro-inertia on the macroscopic flow surface is analyzed and a good agreement between modeling and simulations is observed. In a second step, a representative volume element defined by two confocal oblate spheroids is used to represent the porous material. For this configuration, the static contribution is also described by using the Gologanu et al. model (1997), while the derivation of the dynamic stress is based on the trial velocity field proposed by Gologanu et al. (1994). As for the prolate case, a good agreement is retrieved between model predictions and results of finite element computations. The spherical void configuration is investigated as the limit case for the oblate and prolate models. The continuity between the two models is established. Finally, the proposed models are combined to investigate the porosity and void shape evolutions in a porous solid under dynamic loadings. A parametric study has been performed by varying the stress triaxiality, the initial void shape and the loading rate. Significant void shape variations are observed for low triaxiality loadings. With the present modeling, the void can evolve from prolate to oblate shapes (and the reverse). Model predictions are compared to finite element computations
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22

Hook, Benjamin Austin. "Compression wood formation in Pinus strobus L. following ice storm damage in southwestern Virginia." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/42492.

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Анотація:
To evaluate the compression wood response in eastern white pine (Pinus strobus L.) following a severe ice storm in 1994, 47 trees were felled in 2007 and cross-sectional samples were collected at 0.5 (±0.2) m stem height. The disks were sanded and digitally scanned, and the cross-sectional area (mm2) of compression wood within each tree-ring was quantified using image analysis software. Topographic data (slope, aspect, and elevation) were also recorded for each P. strobus tree, along with a modified competition index. Wood anatomical features were also quantified in the three years before and after the storm along a tree diameter gradient. Although tree age was relatively constant in this stand, tree size was influenced by topographic position; larger trees grew in the valley while smaller trees were found growing in thin soils at the mid-slope position. When the cohort was about 25 years old, ice deposition caused a heterogeneous compression wood response which was highly related to tree size. In the thirteen years following the ice storm, the 6 â 9 cm (2007) diameter class formed significantly more compression wood area than any other, followed by the 10 â 13 cm (2007) diameter class. The tree diameter range that formed the most post-storm compression wood was 4 â 8 cm at the time of the storm, suggesting that this diameter range was most affected by 8.5 cm of ice loading in P. strobus. Trees > 18 cm in 1994 did not form any compression wood after the storm, but many experienced a growth release to fill canopy gaps. Topographic variables did not influence compression wood formation directly, but only one plot was sampled so these results are tenuous. However, topography did influence tree size which was the most important predictor in compression wood. There was no relationship between compression wood area and competition index. Due to compression wood formation after the ice storm, cell wall thickness and cell circularity were significantly higher in the 1994 tree-ring than in other rings examined (1991 â 1993, 1995, and 1996). Tracheid and lumen diameters were significantly smaller in compression wood cells (30.5 and 19.5 μm, respectively) than in normal wood (36.8 and 28.4 μm, respectively); opposite wood cells were intermediate in size (32.4 and 24.4 μm, respectively). Due to small tracheid size, compression wood contained significantly more cells mm-1 (33) than normal wood (27), but no significant differences in cell wall area. Therefore, cumulative cell wall area occupied 47% of the cross-section in compression wood tissue on average, compared to 31% in normal wood. Dispersing tree weight across a greater surface area may help compression wood to prop up a bent tree, but reduced lumen area may also impact hydraulic conductivity in the stem.
Master of Science
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23

USAMI, Tsutomu, 漢彬 葛, Hanbin GE, 聖彬 高, Shengbin GAO та 勉. 宇佐見. "鉛直荷重が偏心して作用する鋼製橋脚の繰り返し弾塑性挙動に関する数値解析的研究". 土木学会, 2000. http://hdl.handle.net/2237/8654.

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24

Sobrado, V. H., R. Yaranga, and J. D. Orihuela. "Analysis of seismic bidirectionality on response of reinforced concrete structures with irregularities of l-shaped plan and soft story." IOP Publishing Ltd, 2020. http://hdl.handle.net/10757/656573.

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The seismic design of buildings is usually performed using one-way analysis for each of main axes independently. However, seismic events have fairly random behaviour and impose bidirectional solicitations on structures. In this work, the study of the response in structures subjects to earthquake loads with irregularity of l-shaped plan and soft story is carried out. For this, the linear time-story analysis (LTHA) of these has been carried out imposing seismic solicitations in two orthogonal directions. Thus, the structural response with incidence angle variations of 10 is obtained and compared with the response derived from the unidirectional analysis. Variations of up to 50% and 72% are obtained for model structures with l-shaped plan and soft story respectively.
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25

Jimenez, Carolina Millan. "Plasticidade fenotípica e evolução da estrutura mandibular de Heliconiini (LEP: NYMPHALIDAE) em relação ao uso da planta hospedeira (Passiflora L.)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/143855.

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Caracteres fenotípicos convergentes em diferentes espécies de insetos herbívoros sugerem uma adaptação funcional a um mesmo hábito alimentar. Nesse sentido, as barreiras apresentadas pelas plantas dificultam o acesso do herbívoro influenciando a evolução de suas estruturas. Espécies de Heliconiini com diferentes padrões alimentares (consumo de tecidos rígidos ou tenros) têm mostrado formas diferenciadas da cápsula cefálica e não existe estudo que explique essas diferenças. Levando em conta que os heliconíneos menos derivados tendem a se alimentar em folhas velhas e os mais derivados em folhas jovens, e que durante o processo de alimentação a mandíbula é a estrutura principalmente associada à mastigação, propomos que dito aumento da cabeça seja devido a modificações sofridas na forma mandibular e ao maior desenvolvimento do músculo adutor da mandíbula, que responde diferencialmente ao tipo de tecido consumido. Avaliamos as alometrias ontogenética e filogenética das mandíbulas das principais linhagens de Heliconiini criadas nas suas plantas hospedeiras preferidas, e mediante o uso de morfometria geométrica, elaboraremos uma proposta filogenética para ser comparada com as relações filogenéticas reconhecidas para o grupo, que também serão reconstruídas nesse trabalho, com base em marcadores moleculares. Identificamos também mediante a morfologia mandibular se as alterações de forma são causadoras das mudanças cefálicas e se correspondem aos diferentes hábitos alimentares apresentados pelas espécies. Para isso, induzimos alometría mudando quanto o comportamento alimentar de uma espécie restrita a folhas novas (tenras) para folhas velhas (rígidas), na procura de possíveis modificações nas mandíbula e músculo adutor. Adicionalmente, usando análises alométricas da mandíbula e músculo adutor, exploramos um aspecto comportamental importante em Heliconiini: a gregariedade, buscando elucidar se o incremento na sobrevivência obtida a altas densidades larvais, já reconhecida no grupo, é ocasionada por facilitação alimentar (comportamento) ou por mudanças alométricas nas estruturas alimentares (morfologia).
Convergent phenotypic traits in different species of herbivorous insects may indicate a functional adaptation to the same feeding habits. The barriers presented by plants hinder the herbivore's access, influencing the evolution of their feeding structures; species of Heliconiini with different feeding patterns (consumption of either tough or soft tissues) have shown different forms of head capsule and there are no studies explaining these differences. Taking into account that the less derived heliconians tend to eat old leaves and the more derived heliconians eat young ones, and that during the feeding process the mandible is main chewing structure, we propose that increase in head size is due to changes in the mandibular form and to greater development of the mandibular adductor muscle that responds differentially to the type of tissue consumed. We evaluate ontogenetic and phylogenetic allometries of the mandibles from the main lineages of Heliconiini that were reared on their favorite host plants. By using geometric morphometry, we tested a corresponding phylogenetic hypothesis to be compared to the molecular phylogenetic relations recognized to the group, also reconstructed in this work based on molecular markers. We also tested, through mandibular morphology, if the changes in shape are caused by cephalic changes in size and if they correspond to the different feeding habits presented by each species. To do this, we induced allometry by experimentally altering feeding behavior of one species restricted to new leaves (soft) to old leaves (tough), searching for possible changes in the mandible and adductor muscle. In addition, using allometric analysis of the mandible and adductor muscle, we explored an important behavioral aspect in Heliconiini -the gregariousness, trying to elucidate whether increase in the survival rates achieved at high larval densities, already recognized in the group, is caused by food facilitation (behavioral effect) or by allometric changes in the feeding structures (morphological cause).
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26

Varadarajan, Amrusha. "Stochastic Scheduling for a Network of MEMS Job Shops." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/77038.

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This work is motivated by the pressing need for operational control in the fabrication of Microelectromechanical systems or MEMS. MEMS are miniature three-dimensional integrated electromechanical systems with the ability to absorb information from the environment, process this information and suitably react to it. These devices offer tremendous advantages owing to their small size, low power consumption, low mass and high functionality, which makes them very attractive in applications with stringent demands on weight, functionality and cost. While the system''s "brain" (device electronics) is fabricated using traditional IC technology, the micromechanical components necessitate very intricate and sophisticated processing of silicon or other suitable substrates. A dearth of fabrication facilities with micromachining capabilities and a lengthy gestation period from design to mass fabrication and commercial acceptance of the product in the market are factors most often implicated in hampering the growth of MEMS. These devices are highly application specific with low production volumes and the few fabs that do possess micromachining capabilities are unable to offer a complete array of fabrication processes in order to be able to cater to the needs of the MEMS R&D community. A distributed fabrication network has, therefore, emerged to serve the evolving needs of this high investment, low volume MEMS industry. Under this environment, a central facility coordinates between a network of fabrication centers (Network of MEMS job shops -- NMJS) containing micromachining capabilities. These fabrication centers include commercial, academic and government fabs, which make their services available to the ordinary customer. Wafers are shipped from one facility to another until all processing requirements are met. The lengthy and intricate process sequences that need to be performed over a network of capital intensive facilities are complicated by dynamic job arrivals, stochastic processing times, sequence-dependent set ups and travel between fabs. Unless the production of these novel devices is carefully optimized, the benefits of distributed fabrication could be completely overshadowed by lengthy lead times, chaotic routings and costly processing. Our goal, therefore, is to develop and validate an approach for optimal routing (assignment) and sequencing of MEMS devices in a network of stochastic job shops with the objective of minimizing the sum of completion times and the cost incurred, given a set of fabs, machines and an expected product mix. In view of our goal, we begin by modeling the stochastic NMJS problem as a two-stage stochastic program with recourse where the first-stage variables are binary and the second-stage variables are continuous. The key decision variables are binary and pertain to the assignment of jobs to machines and their sequencing for processing on the machines. The assignment variables essentially fix the route of a job as it travels through the network because these variables specify the machine on which each job-operation must be performed out of several candidate machines. Once the assignment is decided upon, sequencing of job-operations on each machine follows. The assignment and sequencing must be such that they offer the best solution (in terms of the objective) possible in light of all the processing time scenarios that can be realized. We present two approaches for solving the stochastic NMJS problem. The first approach is based on the L-shaped method (credited to van Slyke and Wets, 1969). Since the NMJS problem lacks relatively complete recourse, the first-stage solution can be infeasible to the second-stage problem in that the first stage solution may either violate the reentrant flow conditions or it may create a deadlock. In order to alleviate these infeasibilities, we develop feasibility cuts which when appended to the master problem eliminate the infeasible solution. Alternatively, we also develop constraints to explicitly address these infeasibilities directly within the master problem. We show how a deadlock involving 2 or 3 machines arises if and only if a certain relationship between operations and a certain sequence amongst them exists. We generalize this argument to the case of m machines, which forms the basis for our deadlock prevention constraints. Computational results at the end of Chapter 3 compare the relative merits of a model which relies solely on feasibility cuts with models that incorporate reentrant flow and deadlock prevention constraints within the master problem. Experimental evidence reveals that the latter offers appreciable time savings over the former. Moreover, in a majority of instances we see that models that carry deadlock prevention constraints in addition to the reentrant flow constraints provide at par or better performance than those that solely carry reentrant flow constraints. We, next, develop an optimality cut which when appended to the master problem helps in eliminating the suboptimal master solution. We also present alternative optimality and feasibility cuts obtained by modifying the disjunctive constraints in the subproblem so as to eliminate the big H terms in it. Although any large positive number can be used as the value of H, a conservative estimate may improve computational performance. In light of this, we develop a conservative upper bound for operation completion times and use it as the value of H. Test instances have been generated using a problem generator written in JAVA. We present computational results to evaluate the impact of a conservative estimate for big H on run time, analyze the effect of the different optimality cuts and demonstrate the performance of the multicut method (Wets, 1981) which differs from the L-shaped method in that the number of optimality cuts it appends is equal to the number of scenarios in each iteration. Experimentation indicates that Model 2, which uses the standard optimality cut in conjunction with the conservative estimate for big H, almost always outperforms Model 1, which also uses the standard optimality cut but uses a fixed value of 1000 for big H. Model 3, which employs the alternative optimality cut with the conservative estimate for big H, requires the fewest number of iterations to converge to the optimum but it also incurs the maximum premium in terms of computational time. This is because the alternative optimality cut adds to the complexity of the problem in that it appends additional variables and constraints to the master as well as the subproblems. In the case of Model 4 (multicut method), the segregated optimality cuts accurately reflect the shape of the recourse function resulting in fewer overall iterations but the large number of these cuts accumulate over the iterations making the master problem sluggish and so this model exhibits a variable performance for the various datasets. These experiments reveal that a compact master problem and a conservative estimate for big H positively impact the run time performance of a model. Finally, we develop a framework for a branch-and-bound scheme within which the L-shaped method, as applied to the NMJS problem, can be incorporated so as to further enhance its performance. Our second approach for solving the stochastic NMJS problem relies on the tight LP relaxation observed for the deterministic equivalent of the model. We, first, solve the LP relaxation of the deterministic equivalent problem, and then, fix certain binary assignment variables that take on a value of either a 0 or a 1 in the relaxation. Based on this fixing of certain assignment variables, additional logical constraints have been developed that lead to the fixing of some of the sequencing variables too. Experimental results, comparing the performance of the above LP heuristic procedure with CPLEX over the generated test instances, illustrate the effectiveness of the heuristic procedure. For the largest problems (5 jobs, 10 operations/job, 12 machines, 7 workcenters, 7 scenarios) solved in this experiment, an average savings of as much as 4154 seconds and 1188 seconds was recorded in a comparison with Models 1 and 2, respectively. Both of these models solve the deterministic equivalent of the stochastic NMJS problem but differ in that Model 1 uses a big H value of 1000 whereas Model 2 uses the conservative upper bound for big H developed in this work. The maximum optimality gap observed for the LP heuristic over all the data instances solved was 1.35%. The LP heuristic, therefore, offers a powerful alternative to solving these problems to near-optimality with a very low computational burden. We also present results pertaining to the value of the stochastic solution for various data instances. The observed savings of up to 8.8% over the mean value approach underscores the importance of using a solution that is robust over all scenarios versus a solution that approximates the randomness through expected values. We, next, present a dynamic stochastic scheduling approach (DSSP) for the NMJS problem. The premise behind this undertaking is that in a real-life implementation that is faithful to the two-stage procedure, assignment (routing) and sequencing decisions will be made for all the operations of all the jobs at the outset and these will be followed through regardless of the actual processing times realized for individual operations. However, it may be possible to refine this procedure if information on actual processing time realizations for completed operations could be utilized so that assignment and sequencing decisions for impending operations are adjusted based on the evolving scenario (which may be very different from the scenarios modeled) while still hedging against future uncertainty. In the DSSP approach, the stochastic programming model for the NMJS problem is solved at each decision point using the LP heuristic in a rolling horizon fashion while incorporating constraints that model existing conditions in the shop floor and the actual processing times realized for the operations that have been completed. The implementation of the DSSP algorithm is illustrated through an example problem. The results of the DSSP approach as applied to two large problem instances are presented. The performance of the DSSP approach is evaluated on three fronts; first, by using the LP heuristic at each decision point, second, by using an optimal algorithm at each decision point, and third, against the two-stage stochastic programming approach. Results from the experimentation indicate that the DSSP approach using the LP heuristic at each decision point generates superior assignment and sequencing decisions than the two-stage stochastic programming approach and provides solutions that are near-optimal with a very low computational burden. For the first instance involving 40 operations, 12 machines and 3 processing time scenarios, the DSSP approach using the LP heuristic yields the same solution as the optimal algorithm with a total time savings of 71.4% and also improves upon the two-stage stochastic programming solution by 1.7%. In the second instance, the DSSP approach using the LP heuristic yields a solution with an optimality gap of 1.77% and a total time savings of 98% over the optimal algorithm. In this case, the DSSP approach with the LP heuristic improves upon the two-stage stochastic programming solution by 6.38%. We conclude by presenting a framework for the DSSP approach that extends the basic DSSP algorithm to accommodate jobs whose arrival times may not be known in advance.
Ph. D.
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27

Pastore, Marcus Vinícius Filiagi. "Contribuição ao projeto de vigas delgadas de seção \"L\" de concreto pré-moldado." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-03092015-085641/.

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Анотація:
Esta dissertação tem por objetivo contribuir para o projeto estrutural de vigas delgadas de seção \"L\" de concreto pré-moldado, também conhecidas no Brasil como vigas suporte-peitoril. O projeto deste tipo de viga apresenta uma maior complexidade que o de vigas usuais pela seção transversal assimétrica, carregamento excêntrico e as várias possibilidades de ligações viga-pilar e viga-laje. Em função de sua ligação com a laje, o comportamento deste tipo de viga pode apresentar diferentes modelos: a) com torção de equilíbrio; b) sem torção de equilíbrio; e c) com restrição parcial da rotação da laje. É mostrado que para relações altura da viga/largura da mesa inferior maiores que 2,5, a variação da orientação dos eixos principais de inércia com relação aos eixos vertical e horizontal pode ser desprezada. Além disso, o centro de cisalhamento pode ser considerado situado na linha de centro da alma para grandes relações altura da viga/altura da aba. Também são discutidas as ações e efeitos a serem considerados no projeto de vigas de seção \"L\". Em relação ao estado limite último, é mostrado que os procedimentos de dimensionamento de momento fletor e força cortante não diferem dos outros tipos de vigas de concreto, entretanto, o momento de torção pode ser tratado como flexão de placa por um método recomendado na última revisão do ACI-318. O comportamento da ligação alma/aba é considerado como dente de concreto e os seguintes aspectos de seu dimensionamento são apresentados: cálculo do tirante, cálculo da suspensão, cálculo da armadura longitudinal e verificação da biela crítica. Além disso, é levada em conta a resistência à punção da aba para efeito de forças concentradas. Também são discutidas as considerações para a flexão do peitoril que pode ocorrer pela ação lateral do vento e do impacto de veículos. Em relação ao estado limite de serviço, são apresentadas duas situações exclusivas para vigas de seção \"L\" com peitoril alto e delgado: formação de fissuras na extremidade e deformação lateral excessiva. Por fim, um exemplo de aplicação é desenvolvido para ilustrar particularidades no dimensionamento de vigas delgadas de seção \"L\" de concreto pré-moldado.
This thesis aims to contribute to the structural design of precast concrete slender L-shaped beams, also known as facade beams, spandrel beams, L-shaped edge beams and others. The design of these beams shows a greater complexity than usual concrete beams due to the asymmetric cross section, eccentric loads and the various possibilities for beam-column and beam-slab connections. According to their connection with the slab, the beam behavior can be divided into different models: a) with equilibrium torsion; b) without equilibrium torsion; c) with partial restriction of the slab rotation. It is shown that for height-to-total width ratios larger than 2.5, the variation of the orientation of the principal axes with respect to the vertical and horizontal axes can be neglected. Furthermore, the shear center can be considered located at the web center line for high values of the beam height-to-ledge height ratio. It is also discussed the actions and effects to be considered in the design of L-shaped beams. Regarding the ultimate limit state, it is shown that the bending moment and shear force procedures do not differ from other types of concrete beams, however, the torsion can be treated as plate bending by a recent method recommended in the latest ACI-318 revision. The ledge is considered as dapped end beams and the following aspects of its design are presented: transverse bending; hanger requirements; longitudinal bending and shear strength, including punching shear. It is also discussed the considerations for web flexure that may occur by wind action and lateral vehicle impact. Regarding the serviceability limit state, it is presented two unique situations for precast concrete slender L-shaped beams: crack formation at end regions and excessive lateral deflection. Lastly, an example is developed to illustrate particularities of the precast concrete slender L-shaped beam design.
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28

Flytström, Annika. "Effekter av inkuberingstemperatur på kroppsform och fenstorlek hos juvenil atlantlax (Salmo salar L.)." Thesis, Karlstads universitet, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-65117.

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Global warming, a consequence of the ongoing climate change, is expected to increase the mean global temperature by up to 5°C this century. This is predicted to have various impacts on the earth's ecosystems and especially on ectotherms which cannot regulate body temperature by endogenous heat production. There is an intensified interest in investigating the outcomes of climate change and the role of developmental phenotypic plasticity in relation to environmental conditions experienced early in life. Here I compare the body shape and fin size of juvenile Atlantic salmon that had been incubated at two different temperature regimes during embryogenesis. Morphometric methods were used to compare body size through a box-truss network of Euclidean distances and the data were then analyzed using discriminant analysis. Fin size was analyzed by comparing fin area using analysis of covariance with body size as the covariate. The fish incubated in ambient (cold) temperatures differed from the fish incubated in ca. 4°C warmer temperatures by having a deeper body shape and bigger pectoral fin area. There was no significant difference for dorsal fin area. My findings support the notion that Atlantic salmon are morphologically plastic when exposed to different temperature regimes during embryogenesis, but additional studies are needed to determine the ecological consequences of these changes.
Global uppvärmning, en konsekvens av pågående klimatförändringar, förväntas öka den globala medeltemperaturen med upp till 5°C det här århundradet. Det här förväntas ha stor påverkan på jordens ekosystem och speciellt ektotermer som inte kan reglera sin kroppstemperatur genom endogen värmeproduktion. Intresset har intensifierats för att undersöka klimatförändringarnas utfall och rollen som fenotypisk plasticitet har som svar på tidiga miljöförhållanden. Kroppsform och fenstorlek jämfördes hos juvenil atlantlax som inkuberats i två olika temperaturbehandlingar under embryogenesen. Morfometri användes för att undersöka kroppsformen genom ett box-truss nätverk av euklidiska avstånd som sedan analyserades med en diskriminant funktionsanalys. Fenstorleken analyserades genom att mäta fenornas area som sedan användes i en kovariansanalys med kroppsstorlek som kovariat. Fiskarna som inkuberades i normal (kall) temperatur skiljde sig från fiskarna som inkuberats i ca 4°C varmare temperatur genom att ha en djupare kroppsform och större area på bröstfenorna. Det fanns ingen signifikant skillnad mellan ryggfenornas area. Mina resultat stödjer idén att atlantlaxen är morfologiskt plastisk när den utsätts för olika temperaturbehandlingar under embryogenesen, men ytterligare studier behövs för att identifiera de ekologiska konsekvenserna av dessa förändringar.
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29

Bockstaller, Christian. "Taille et forme des semences de maïs (Zea mays l. ) : variabilité et effets sur la croissance, le développement et le rendement." Vandoeuvre-les-Nancy, INPL, 1993. http://docnum.univ-lorraine.fr/public/INPL_T_1993_BOCKSTALLER_C.pdf.

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La variabilite de la taille et de la forme des semences de maïs a été caractérisée au sein d'une variété. Les effets de la taille de la semence et de sa forme plate ou ronde sur la croissance, le développement et le rendement en grain ont été étudiés au champ. Aucun effet de la forme de la semence n'a été mis en évidence. Le développement de la plante est faiblement influence par la taille de la semence. À la sortie de la phase d'hétérotrophie, la croissance est liée positivement au poids de la semence. Cet effet de la taille de la semence se maintient durant la croissance exponentielle, puis disparait en phase de montaison. Aucun effet de la taille de la semence n'a été mis en évidence sur le rendement en grain. En phase hétérotrophe, les écarts de croissance dus à la taille de la semence ne sont pas modifiés par un stress provoqué par des basses températures ou une contrainte hydrique
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30

葛, 漢彬, Hanbin GE, 俊輔 渡辺, Syunsuke WATANABE, 勉. 宇佐美, Tsutomu USAMI, 徹彦 青木 та Tetsuhiko AOKI. "面外繰り返し水平力を受ける逆L形鋼製箱形断面橋脚の耐震性能に関する解析的研究". 土木学会, 2003. http://hdl.handle.net/2237/8631.

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31

Faria, João Pedro Bernardes. "Alterações hormonais no mutante ovate de tomateiro (Solanum lycopersicum L. cv Micro-Tom) e seu impacto na morfologia, qualidade do fruto, produtividade e partenocarpia." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/11/11144/tde-25062014-092501/.

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Анотація:
Os frutos do tomateiro (Solanum lycopersicum) apresentam elevada diversidade fenotípica, grande parte da qual deve-se a mutações em cinco genes, SUN (SUN), OVATE (O), LOCULE NUMBER (LC), FRUIT SHAPE 8.1 (FS8.1) e FASCIATED (FAS). Enquanto mutações em LC, O e FAS são responsáveis pela alteração no número de lóculos no fruto, mutações em FS8.1, SUN e O resultam em frutos mais alongados, sendo a última mutação o foco de estudo do presente trabalho. Apesar de ovate ser uma mutação importante tanto do ponto de vista agronômico quanto biológico, não é conhecido ainda o efeito exato da nova classe de gene regulatório codificado por esse locus. Por promover a drástica alteração no formato do fruto, característica esta que pode influenciar a preferência do consumidor, essa mutação é de grande interesse agronômico. Sob o ponto de vista biológico, o maior conhecimento da função desse gene resultaria em um maior entendimento do processo de frutificação. A análise de duplos mutantes ovate DR5::GUS e ovate ARR5::GUS mostrou que essa mutação altera o padrão de resposta a auxina e citocinina, respectivamente, durante o desenvolvimento do fruto. Além disso, foram realizados estudos que mostraram seu impacto no teor de sólidos solúveis, produtividade, tempo de prateleira, teor de matéria seca, peso das sementes e partenocarpia. Tais resultados não somente contribuíram para um melhor entendimento do efeito gênico da nova classe de genes regulatórios codificado por OVATE, como também fornecem importantes implicações agronômicas, já que a mutação ovate vem sendo utilizada na obtenção de variedades e híbridos do tipo \"grape\".
The fruits of tomato (Solanum lycopersicum) present a high phenotypic diversity, most of which can be attributed to mutations in five genes: SUN (SUN), OVATE (O), LOCULE NUMBER (LC), FRUIT SHAPE 8.1 (FS8.1) and FASCIATED (FAS). Whereas mutations in LC, O and FAS alter fruit locule number, mutations in FS8.1, SUN and O result in elongated fruits. The latter is the focus of the present work. ovate is a biologically and agronomically relevant mutation, however, the exact effect of the new class of regulatory gene it represents is unknown. The drastic alteration in fruit shape produced by the mutation can influence consumer preference, thus rendering it agronomically important. Biologically, a thorough characterization of its gene function would result in deeper understanding of fruit formation. Crosses to the marker lines DR5::GUS and ARR5::GUS showed that ovate alters the response pattern of auxin and cytokinin, respectively, during fruit development. Furthermore, studies are described showing its effect on total soluble solids content, yield, shelf life, dry mass rate, seed weight and parthenocarpy. The results contribute not only to a better understanding of the effect of the new class of regulatory genes encoded by OVATE, but also have important agronomic implications, given that the ovate mutation has been used in the obtention of \'grape/plum\' tomato varieties and hybrids.
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32

Mun, Kyu-Shik. "Monitoring Cell Behaviors on Variety of Micropatterns Created with Biodegradable Polymer." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1457426363.

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33

Lusley, Pauline. "Compréhension des mécanismes directs et indirects de résistance à la pourriture racinaire du pois causée par Aphanomyces euteiches : influence du choix variétal et de la cohorte microbienne associée. Compared analysis of architectural symptoms and disease severity caused by Aphanomyces euteiches between winter and spring peas. Co-existence of Rhizobia and non-rhizobial bacteria in the nodules of Pisum sativum L. depending on cultivars and influencing mycelium growth of Aphanomyces euteiches. The microbial cavalry: how crop could be determinant to beneficially shape soil microbiome in the battlefield against Aphanomyces euteiches." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMR091.

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Le pois protéagineux, dont la culture est bien adaptée au contexte pédoclimatique normand, représente une source nutritive importante en protéines végétales. A l’heure actuelle, les cultures protéagineuses font partie des cultures d’avenir aux vues de leurs nombreux intérêts agronomique, économique et environnemental. Malgré ses multiples atouts, la culture du pois protéagineux n'a pas autant de succès, principalement en raison d’une forte atteinte par diverses phytopathologies, dont le plus préjudiciable est la pourriture racinaire du pois causée par Aphanomyces euteiches. Les dégâts occasionnés peuvent conduire à une baisse importante du rendement et ainsi pénaliser les agriculteurs. Ne disposant d’aucun traitement efficace à ce jour, il est donc important de focaliser les recherches sur le développement de moyens de contrôle, ce qui passe par une compréhension holistique du pathobiome. Dans cette thèse, les travaux se sont concentrés sur la compréhension de certains mécanismes de résistance directs ou indirects à la pourriture racinaire du pois causée par A. euteiches, en se focalisant sur l’étude de la contribution des facteurs biotiques, à savoir, le génotype variétal, seul ou accompagné de son phytobiome, et donc la mise en place de multiples interactions avec les microorganismes. L’analyse comparée de l’expression de la maladie et des modifications architecturales induites a montré une expression différentielle de la maladie selon leur appartenance au groupe hiver ou printemps. Les variétés d’hiver caractérisées par une grande tolérance au froid présentent 2 traits d’intérêt : un retard d’impact sur les parties aériennes malgré une atteinte racinaire et un accroissement du système racinaire en réponse à l’infection. De plus, l’étude de la diversité bactérienne intra-nodules chez ces mêmes variétés de pois d’hiver et de printemps, a montré que la diversité de ce microbiome endophyte varie en fonction du génotype variétal. Cette étude a permis de déceler le fort potentiel biocontrôle des endophytes bactériens intra-nodulaires, avec une abondance relative observée des genres bactériens connus pour leurs effets antagonistes envers A. euteiches plus importante chez deux variétés de pois d’hiver. Le génotype variétal constitue donc un levier, direct et indirect via l’établissement d’interactions avec des microorganismes bénéfiques, pour lutter contre la pourriture racinaire du pois. Le dernier axe de recherche a démontré la forte influence des espèces cultivés sur les associations microbiennes au sien de la rhizosphère, en particulier sur l’assemblage des populations bénéfiques. La manipulation de la composition des communautés microbiennes par les couverts végétaux au bénéfice de la culture suivante représente un argument de plus en faveur de l’utilisation des rotations des cultures comme levier contre les phytopathologies. Plusieurs pistes intéressantes ressortent donc de ce travail, pour une lutte efficiente et globale contre A. euteiches : à l’échelle de la variété, par ses caractéristiques propres en lien avec son génotype et sa capacité à sélectionner des endophytes protecteurs, et à l’échelle de la rotation, par la manipulation du microbiome en faveur du pois. De belles perspectives de recherche se profilent, notamment la réalisation de tests d’efficacité de protection de tous les potentiels agents de biocontrôles isolés, qui permettraient la mise en oeuvre de consortia bénéfiques adaptés au terroir normand et aux spécificités variétales du pois
Pea, well-adapted to the Normandy pedoclimatic context, represents an important nutritional source of plant proteins. At present, protein crops are among the promoting crops in view of their many agronomical, economic, and environmental interests. Despite their multiple advantages, the cultivation of protein peas is not as successful, mainly due to strong attacks by various phytopathology. The most damaging is pea root rot caused by Aphanomyces euteiches leading to a significant drop in yield and thus can penalize farmers. As there is no effective treatment to date, numerous focus researches are in progress to develop efficient control methods, which requires a holistic understanding of the pathobiome. In this thesis, studies were focused on the understanding of some direct and indirect resistance mechanisms of pea root rot caused by A. euteiches. The contribution of biotic factors in this disease were studied, specifically the influence of varietal genotype and its associated phytobiome, and so the establishment of multiple interactions with microorganisms. The comparative analysis of disease severity and induced architectural modifications, showed a differential expression according to their affiliation to winter or spring group. The two winter pea cultivars characterized by a high cold tolerance presented two features of interest: a delayed impact on aerial part despite significant root damage and an increased growth of root system in response to infection. In addition, the study of intra-nodule bacterial diversity in these same cultivars showed that the diversity of their nodule microbiome varies according to varietal genotype. This study highlighted the strong biocontrol potential of intra-nodule bacterial endophytes, with a higher relative abundance of known antagonistic bacterial genera towards A. euteiches for two winter pea cultivars. The varietal genotype therefore constitutes a direct and indirect lever by the establishment of interactions with beneficial microorganisms, to fight against pea root rot. The last research line has demonstrated the strong influence of plant cultivated species on the microbial associations in the rhizosphere, specifically a modulation of the assemblage of beneficial populations. Shaping the microbial community composition though the cultivation of crops to the benefit of the next crop represents an additional argument in favor of crop rotation use as a lever against phytopathology. Several interesting alternatives were highlighted in this research work to effectively and efficiently manage A. euteiches: at the cultivar scale, by specific characteristics in relation to varieties’ genotype and their ability to select protective endophytes, and at the scale of crop rotation, by shaping microbiome in favor of pea. Great research perspectives are emerging, especially the efficiency of protection resulting from all potential isolated biocontrol agents, which would allow the development and implementation of beneficial consortia adapted to Normandy soils and to pea cultivars specificities
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34

Odelius, Karin. "Design of polyester and porous scaffolds." Licentiate thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-493.

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35

Stejskalová, Markéta. "Penzion pro seniory." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-372260.

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This work aims to develop projekt documentation for building construction. The projekt addresses the new construkction of a pension for seniors. Pension is located in the city of Kutná Hora in the Central Region. The object is designed for 34 people throughout the year. Pension has one underground and free above ground floors. The shape of the object is unspecified at several height levels. It is a reversed L-shaped with mid-point projections. Pension is bricked from ceramic blocks. The roof is a combination of a sliding flat roof and a console roof. The building is situated in a place of flat terrain.
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36

Watson, Francis Maurice. "Better imaging for landmine detection : an exploration of 3D full-wave inversion for ground-penetrating radar." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/better-imaging-for-landmine-detection-an-exploration-of-3d-fullwave-inversion-for-groundpenetrating-radar(720bab5f-03a7-4531-9a56-7121609b3ef0).html.

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Humanitarian clearance of minefields is most often carried out by hand, conventionally using a a metal detector and a probe. Detection is a very slow process, as every piece of detected metal must treated as if it were a landmine and carefully probed and excavated, while many of them are not. The process can be safely sped up by use of Ground-Penetrating Radar (GPR) to image the subsurface, to verify metal detection results and safely ignore any objects which could not possibly be a landmine. In this thesis, we explore the possibility of using Full Wave Inversion (FWI) to improve GPR imaging for landmine detection. Posing the imaging task as FWI means solving the large-scale, non-linear and ill-posed optimisation problem of determining the physical parameters of the subsurface (such as electrical permittivity) which would best reproduce the data. This thesis begins by giving an overview of all the mathematical and implementational aspects of FWI, so as to provide an informative text for both mathematicians (perhaps already familiar with other inverse problems) wanting to contribute to the mine detection problem, as well as a wider engineering audience (perhaps already working on GPR or mine detection) interested in the mathematical study of inverse problems and FWI.We present the first numerical 3D FWI results for GPR, and consider only surface measurements from small-scale arrays as these are suitable for our application. The FWI problem requires an accurate forward model to simulate GPR data, for which we use a hybrid finite-element boundary-integral solver utilising first order curl-conforming N\'d\'{e}lec (edge) elements. We present a novel `line search' type algorithm which prioritises inversion of some target parameters in a region of interest (ROI), with the update outside of the area defined implicitly as a function of the target parameters. This is particularly applicable to the mine detection problem, in which we wish to know more about some detected metallic objects, but are not interested in the surrounding medium. We may need to resolve the surrounding area though, in order to account for the target being obscured and multiple scattering in a highly cluttered subsurface. We focus particularly on spatial sensitivity of the inverse problem, using both a singular value decomposition to analyse the Jacobian matrix, as well as an asymptotic expansion involving polarization tensors describing the perturbation of electric field due to small objects. The latter allows us to extend the current theory of sensitivity in for acoustic FWI, based on the Born approximation, to better understand how polarization plays a role in the 3D electromagnetic inverse problem. Based on this asymptotic approximation, we derive a novel approximation to the diagonals of the Hessian matrix which can be used to pre-condition the GPR FWI problem.
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37

AVEZZU', GIORGIO. "L'ANGOSCIA CARTOGRAFICA DEL CINEMA. PERSISTENZA E CRISI DELLA RAGIONE CARTOGRAFICA NEL FILM CONTEMPORANEO." Doctoral thesis, Università Cattolica del Sacro Cuore, 2014. http://hdl.handle.net/10280/3153.

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Lo studio approfondisce la questione dei rapporti tra la geografia e il cinema, in particolare il cinema contemporaneo. La “propensione geografica” del cinema, tipicamente individuata da molti studiosi, deve oggi confrontarsi con un problema fondamentale: quello di una riconsiderazione radicale dei limiti del discorso geografico, e della geografia intesa come scienza, come sapere e come progetto della modernità. In che modo un medium con un’antica vocazione geografica oggi interpreta, commenta, elabora la “crisi della ragione cartografica”? Le “forme cartografiche” del cinema, cioè le porzioni di testo filmico che riflettono sulla geograficità del medium, nel cinema recente non si limitano a dichiarare o a celebrare tale geograficità, ma la considerano come un problema. Se le forme cartografiche sono considerate in modo problematico nel cinema contemporaneo è perché il cinema stesso si è accorto, o si è convinto, che il proprio ruolo è cambiato, che non può più (forse non deve) guardare in un certo modo. Perché la crisi della ragione cartografica del cinema è un sinonimo della crisi strutturale della cinematograficità, di un modo di vedere il mondo, di un dispositivo, di una geometria che descriveva le posizioni di soggetti e oggetti, il loro valore e il loro significato.
This work explores the relationship between geography and cinema, especially contemporary cinema. The “cartographic penchant” of cinema, typically traced by many scholars, has to face a fundamental problem today: a radical reconsideration of the geographical discourse, and of geography intended as a science and an epistemic project of modernity. How does a medium with an ancient geographical vocation deal with the “crisis of cartographic reason”? The “cartographic shapes” of cinema, which are portions of filmic texts that mirror the “geographicity” of the medium, in contemporary cinema do not simply declare or celebrate that kind of geographicity, but they consider it as a problem. The reason the cartographic shapes are problematically represented by recent cinema is that cinema itself is aware, or became convinced, that its cultural role has changed, that it cannot understand the world in a certain way anymore. Because the crisis of cartographic reason of cinema is a synonym of a structural crisis of “cinematographicity”, of a way of looking at the world, of a dispositif, of a geometry that used to describe the positions of subjects and objects, their value and their meaning.
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38

AVEZZU', GIORGIO. "L'ANGOSCIA CARTOGRAFICA DEL CINEMA. PERSISTENZA E CRISI DELLA RAGIONE CARTOGRAFICA NEL FILM CONTEMPORANEO." Doctoral thesis, Università Cattolica del Sacro Cuore, 2014. http://hdl.handle.net/10280/3153.

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Анотація:
Lo studio approfondisce la questione dei rapporti tra la geografia e il cinema, in particolare il cinema contemporaneo. La “propensione geografica” del cinema, tipicamente individuata da molti studiosi, deve oggi confrontarsi con un problema fondamentale: quello di una riconsiderazione radicale dei limiti del discorso geografico, e della geografia intesa come scienza, come sapere e come progetto della modernità. In che modo un medium con un’antica vocazione geografica oggi interpreta, commenta, elabora la “crisi della ragione cartografica”? Le “forme cartografiche” del cinema, cioè le porzioni di testo filmico che riflettono sulla geograficità del medium, nel cinema recente non si limitano a dichiarare o a celebrare tale geograficità, ma la considerano come un problema. Se le forme cartografiche sono considerate in modo problematico nel cinema contemporaneo è perché il cinema stesso si è accorto, o si è convinto, che il proprio ruolo è cambiato, che non può più (forse non deve) guardare in un certo modo. Perché la crisi della ragione cartografica del cinema è un sinonimo della crisi strutturale della cinematograficità, di un modo di vedere il mondo, di un dispositivo, di una geometria che descriveva le posizioni di soggetti e oggetti, il loro valore e il loro significato.
This work explores the relationship between geography and cinema, especially contemporary cinema. The “cartographic penchant” of cinema, typically traced by many scholars, has to face a fundamental problem today: a radical reconsideration of the geographical discourse, and of geography intended as a science and an epistemic project of modernity. How does a medium with an ancient geographical vocation deal with the “crisis of cartographic reason”? The “cartographic shapes” of cinema, which are portions of filmic texts that mirror the “geographicity” of the medium, in contemporary cinema do not simply declare or celebrate that kind of geographicity, but they consider it as a problem. The reason the cartographic shapes are problematically represented by recent cinema is that cinema itself is aware, or became convinced, that its cultural role has changed, that it cannot understand the world in a certain way anymore. Because the crisis of cartographic reason of cinema is a synonym of a structural crisis of “cinematographicity”, of a way of looking at the world, of a dispositif, of a geometry that used to describe the positions of subjects and objects, their value and their meaning.
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39

Kopečková, Kristýna. "Horský penzion s wellness." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265232.

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The subject of my thesis is the design mountain guesthouse with a wellness centre, which is located in the village of Mala Morávka, at the level of documentation for construction. The new building is located in the cadastre unit Karlov pod Pradědem. This is a two floors, slab-building L-shaped with separate parking for visitors of boarding house and wellness centre. The structural system is composed of ceramic blocks Porotherm and reinforced concrete joist floor. Roof structure is made up of wooden trusses girders saddle shape. Design of mountain guesthouse with wellness centre respects the territorial plan of the village of Malá Morávka.
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40

Tong, Ruoshi. "Cost Analysis on L-shape Composite Componenet Manufacturing." Thesis, 2012. http://spectrum.library.concordia.ca/974117/1/Ruoshi_MSc_S2012.pdf.

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41

DING, RONG-HUA, and 丁榮華. "Design and analysis of rectangular and L-shape cell placement." Thesis, 1990. http://ndltd.ncl.edu.tw/handle/37151745376468049454.

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42

Wang, Yong. "Theory and algorithms for shape-preserving bivariate cubic L₁ splines." 2005. http://www.lib.ncsu.edu/theses/available/etd-04082005-144213/unrestricted/etd.pdf.

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43

Cheng-ChunJu and 朱振忠. "Shape and Size-Controlled of Gold Nanoparticles by L-Tyrosine and L-Tyrosine-Based Novel Surfactant." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/48128341662745081779.

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Анотація:
碩士
國立成功大學
化學工程學系碩博士班
98
In this study, we controlled the shape and size of gold nanoparticles by varying concentration ratio([reductant]/[HAuCl4]) and [HAuCl4]. In the first section, L-tyrosine(LY) system, the L-tyrosine which used to synthesize nanospheres and nanowires acted both as reducing and capping agent without additional reagent. When the concentration ratio R([LY]/[HAuCl4])≧0.2, spherical gold nanoparticles were obtained and the average diameter could be controlled from 9 to 16 nm under varying reaction conditions of concentration ratio R and [HAuCl4]. When the concentration ratio R([LY]/[HAuCl4])≦0.1, gold nanowires and network-like structures were obtained as thin as 7 nm to 11 nm. Increasing of [HAuCl4] would result in the flatter wire-like structures. The major reason for the forming of gold nanowires and network-like structure is that insurfficient L-tyrosine capped on the surface of gold naoparticles which result unstable nanoparticles. The excess chloroaurate ions would absorb on the exposed surface of nanoparticles in uncharged state, AuCl3 resulted in increasing of Van der Waals force between particles and decreasing of repulsive force. Then gold nanoparticles sintered in the direction of exposed surface. The forming gold nanowires and network-like structures capped by L-tyrosine completely showed excellent stability and well-dispersed in basic solution without existensce of AuCl4- for six month. In the second section, LYSA system, the novel surfactant, LYSA, was synthesized through an amide reaction. The LYSA acted as reducing, capping, chelating agent and soft-template during the preparation of nanogold. The shape and size of nanogold were controlled by varying reaction conditions of concentration ratio R([LYSA]/[HAuCl4]) and [HAuCl4]. The surfactant LYSA which self-assembled into tubular structure as a soft-template in basic aqueous solution chelated with gold ions which resulted in the transformation of LYSA self-assembled structure and further induced oxidation of gold ions in situ. The different shape of gold nanoshells were formed and consisted of nanogold. At higher concentration ratio R and low [HAuCl4], the amount of chloroaurate ions chelated with the outer surface of LYSA self-assembled structures was larger than inner surface due to the small driving force and loose arrangement. The difference of chelated gold ions lead to the self-assembled structure transform into smaller curvature structure, such as small vesicles. However, because of the decreasing of concentration ratio R and the increasing of [HAuCl4], the amount of gold ions which diffused into inside and chelated with the inner surface of self-assemble structure increased which lead to large vesicles. When the amount of chelated gold ions between outer and inner surface of self-assembled structure were almost the same, the self-assembled structure would still maintain the tubular structure. From the TEM images, different shape of gold nanoshells consisted different morphology of nanogold. For example, the spherical nanoshells consisted of 1-D or 2-D nanogold, but the tubular nanoshells consisted of isolated nanoparticles with two kinds of size distribution. The first narrow distribution was located at 10 nm, and the second broad distribution ranged from 30 nm to 90 nm. Gold nanoshells synthesized by soft-template method were reported in few studies. In this study, a method used to synthesize gold nanoshells through a simple, low-cost, few-step and morphology transformation process was reported. The shape and size of nanoshells could be controlled by varying reaction condition of concentration ratio R([LYSA]/[HAuCl4]) and [HAuCl4]. The gold nanocrystals and novel L-tyrosine-based surfactants were characterized by nuclear magnetic resonance spectroscopy (1H NMR), surface tension meter, UV-vis spectroscopy, high resolution field emission scanning electron microscope (HR-SEM), atom force microscopy (AFM) and transmission electron microscopy (TEM).
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44

Wu, Chun-Wang, and 吳俊旺. "Study on the pass schedule design of L-type shape rolling." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/98662444188227423328.

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Анотація:
碩士
國立臺灣科技大學
機械工程系
91
The main purpose of this study is to establish an analytical model to analyze the deformation behaviors of L-type multi-pass shape rolling. Through simulation, the stress, strain and strain rate of each pass can be obtained, and this information can be the reference for roll design engineers. Complex analytical model is used in this study. This model combined the slab method and 3D rigid-plastic FEM, it has the advantages of high precision and low computation time. The researches about shape rolling were concentrated on the simple shape, for example, square to oval, square to diamond, oval to round etc. . The study about L-type shape rolling is relatively rare so we choose it as the study object. We re-design the roll calibers of L-type shape rolling, and set the total steps to be 7 passes. The complex analytical model is applied to simulate the deformation behaviors, the data base of deformed shape, stress, strain and strain rate can be obtained, and it can apply useful reference for researcher on this field.
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45

Jian-Anne, Chen, and 陳建安. "Punching Shear Strength of Reinforced Concrete Slabs Loaded Through L-Shape Columns." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/15609481106115358507.

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Анотація:
碩士
國立臺灣科技大學
營建工程技術學系
86
Currently, the punching shear strength ofreinforced concrete slabs is calculated using the provisions of Section 11.12of ACI 318-95.However,the provisions of Section 11.12 of ACI Building Code areprimarily based on test results of reinforced low-strength concrete slabs loaded through a rectangular column. Therefore,it becomes necessary to examinethe applicability of current ACI Code when applied to reinforced high-strength concrete slabs loaded through a L-shape column. In this study,twentyspecimens were tested to investigate the punching shear behavior of reinforcedconcrete slabs loaded through a L-shape column. Variables included in this study are the concrete strength, the flexural reinforcement ratio and the aspect ratio.Based on test results in this study, the applicability of current design equations when applied to reinforced concrete slabs loaded through a L-shape column are carefully examined.
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46

SINGH, JYOTI. "ESTIMATION OF AERODYNAMICS EFFECT ON LOW RISE DOMICAL STRUCTURES." Thesis, 2022. http://dspace.dtu.ac.in:8080/jspui/handle/repository/19342.

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Анотація:
The wind is a complex phenomenon because of the many flow situations that result from wind interaction with structures. In designing buildings, it is important to take wind into account, since this is one of the more significant forces of nature. In time and space, the characteristics of wind-induced loads on buildings continually change. A building's design depends on predicting the actual effects of turbulent wind forces to account for the most critical design scenarios that may occur during a specific design period. Low-rise structures are susceptible to high winds alike tall structures. These low-rise structures are exposed to the atmospheric wind speed that is highly prone to uplift pressure. The present study demonstrates the investigation of mean wind pressure on isolated domical low-rise buildings, and the arrangement of domical low-rise buildings in a T-shape and L shape. The wind incidence angle is varied from 0 O to 180 O at an interval of 30 O for T shape and 0 O to 360 O at an interval of 30 O because of the asymmetric plan and the spacing between the buildings is varied at a distance of 0, b/2, b, 3b/2 and 2b where b is the width of the isolated building i.e. 0mm, 50mm, 100mm, 150mm and 200mm. We performed the numerical analysis using ANSYS CFX using the shear stress transport turbulence model. The pressure distribution over the surfaces using Coefficient of pressure (Cp) and velocity streamlines are analyzed for each building model, and the effect of interference on surrounding buildings is studied. The finding is useful for structural engineers when designing the structure of a low-rise building and the outcome of the study is depicted by pictorial and tabular representation. Interestingly, the maximum positive wind pressure coefficients were vi found on the windward side of the dome, whereas the maximum negative wind pressure coefficients occurred at the apex. The interference research was carried out in order to comprehend the consequences of various conditions that may emerge in real-life scenarios, and it was found that the maximum negative pressure is found to be on the centre of the domes which are directly hit by the wind and the value is found to be decrease in the corner region. For the variation of spacing, the average coefficient of pressure acting on each dome was found, and it was observed that the average pressure acting on the dome surface is suction for isolated, L shape and T shape domical roofs. The finding is useful for structural engineers when designing the structure of a low-rise building. As a result, it is important for designers and planners to study the wind induced response of the buildings.
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47

HSIEH, CHANG-LIN, and 謝長霖. "Design of VCM Actuator with the L-Shape Coil for Cellphone Camera Modules." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/99352354592049896329.

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Анотація:
碩士
國立中正大學
機械工程系研究所
104
Recently, the sales of the smartphone grow intensely, thus more manufacturers go into operation. Competitive market makes the smartphone develop rapidly. Manufacturers have to progress in the functions of smartphone to avoid them being eliminated through competition. And to capture images using camera modules is one of the noticed function. These days, auto-focusing (AF) is the basic function on smartphones. And the optical image stabilizer (OIS) mechanism is designed in the high-end smartphones to enhance the function of the camera module. Among of the brands (for example: Apple, Samsung and HTC etc.), iPhone catches more consumers’ attention. Thus this thesis got more information and specification through the reverse engineering of the camera module on iPhone 6 Plus, and proposed a novel camera module in which the coils were folded into L-shape. After designing the complete module, this thesis evaluated its performance using a laboratory-built prototype. The simulation and experimental results showed that the proposed camera module is better than the camera module on iPhone 6 Plus.
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48

Wu, Zong-Hong, and 吳宗泓. "A Study on Springback Compensations of Forming Die for Composite L-Shape Beams." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/9s65xq.

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Анотація:
碩士
大葉大學
工業工程與管理學系
107
In this study, the heat-curing forming process parameters were simulated by L-Shape Beams curved thin-shell parts of carbon fiber composites and the die compensation research was carried out. The finite element analysis commercial software ANSYS was used for analysis and discussed separately. Thermal Springback, thermal warpage and heat shrinkage caused by temperature effects. According to the analysis results, the thermal curing of carbon fiber composites is deformed by the influence of material parameters and temperature parameters, and the cross-comparison of analytical data and experimenttal data is verified to show the mechanical properties, lamination angle, and bending of the material. The radius and temperature parameters will have a signifycant impact. The trend analysis of the research results can be applied to the design of the forming die, and can effectively reduce the number of experiments and research and development costs.
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49

Huang, Hsiang-Yi, and 黃祥益. "Genetic Study on Fruit Color and Shape of Bitter Gourd (Momordica charantia L.)." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/ra6v34.

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Анотація:
博士
國立屏東科技大學
農園生產系所
105
The fruit color and shape are important traits of bitter gourds (Momordica charantia L.) which are also the major targets of bitter gourd breeding projects. The objects of this study were to determine the genetic models of fruit color and shape in the bitter gourd. Six generations (P1, P2, F1, F2, BCP1 and BCP2) in the hybrid set ‘MS 41 × MS47’ were used to estimate the genetic effects via generation mean analysis (GMA), and determined the genetic mechanisms. The fruit color of the F1 population was green implying the green color was dominant over the white color. The fruit color of F2 population showed a continuous distribution from white to dark green indicating this traits was controlled by quantitative genes. Genetic analysis using the lightness, hue angle and the Royal Horticultural Society scoring system (RHS score) fitted the three parameters model, which Chi-square ( ) test estimates were 1.05 (P = 0.68233), 1.80 (P = 0.6157) and 1.59 (P = 0.6607), respectively. The results showed significant to highly significant additive and dominance effects. The value a and b of color difference, chroma and chlorophyll concentrations were not fitted three parameters genetic model which implied the epistasis was present. The GMA results of six parameters model revealed a significant additive effect on chlorophyll b concentration, and other fruit color related traits were nonsignificant in all parameters which was more complex genetic mechanism involved. The value b of color difference was affected by complementary epistasis, but the value a of color difference, chroma and chlorophyll concentrations were controlled by duplicate epistasis. Exclude chroma, the broad-sense heritability of all fruit color related traits were lower, between 0.226 and 0.510. About fruit shape related traits, the average single fruit weight of all hybrid and backcross generations were heavier than two parents that indicated the overdominance genetic effect. All fruit shape related traits of the F2 population showed continuous distributions that revealed the six traits were quantitative traits. Genetic analyses using all fruit shape related traits fitted the three parameters model that was additive-dominance genetic model and epistasis was absent. The Chi-square estimates were 5.606 (P = 0.132), 3.069 (P = 0.381), 1.319 (P = 0.725), 3.613 (P = 0.306), 2.036 (P = 0.565) and 4.741 (P = 0.38), respectively. Exclude the dominance effect of single fruit weight, all traits show significant or highly significant additive and dominance effects. The broad-sense heritability estimates were 0.788 and 0.878 for single fruit weight and top fruit width respectively, which were higher. The broad-sense heritability estimates were 0.578, 0.266 and 0.618 for fruit length, fruit width and fruit shape index, respectively, that were easier affected by environmental conditions. The correlation analyses of fruit color related traits showed highly significant effects between the RHS score, lightness, chlorophyll concentrations (|r| ≥ 0.724), which is a proper index of fruit color expression. The correlation analyses of fruit shape related traits showed highly significant effects between the fruit shape index, fruit length, fruit width and top fruit width, which estimates were 0.870, -0.839 and -0.792, respectively. The correlations analyses between fruit color and fruit shape got highly significant effects on chlorophyll concentrations, fruit length, fruit width and top fruit width. But correlation analyses were non-significant response between fruit color and fruit shape within F2 population. The fruit color and fruit shape related traits were controlled by additive, dominance and epistasis effects. The selection of breeding method is mostly depending on the value of broad-sense heritability of trait when it is conducted. The broad-sense heritability of fruit color related traits, fruit length, fruit width and fruit shape index were low at this study which suggested the use of recurrent selection. Traits with high broad-sense heritability, the single fruit weight and the top fruit width, will be recommended to conduct earlier generation selection which could promote the efficiency of selection.
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50

Ferrari, Patrik L. [Verfasser]. "Shape fluctuations of crystal facets and surface growth in one dimension / Patrik L. Ferrari." 2004. http://d-nb.info/973069252/34.

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