The growing number of applications of composite materials in aerospace and naval structures along with advancements in manufacturing technologies demand continuous innovations in the design of composite structures. In the traditional design of composite laminates, fiber orientation angles are constant for each layer and are usually limited to 0, 90, and ±45 degrees. To fully benefit from the directional properties of composite laminates, such limitations have to be removed. The concept of variable-stiffness laminates allows the stiffness properties to vary spatially over the laminate. Through tailoring of fiber orientations and laminate thickness spatially in an optimal fashion, mechanical properties of a part can be improved. In this thesis, the optimal design of variable-stiffness fiber-reinforced composite laminates is studied using an emerging numerical engineering optimization scheme based on the cellular automata paradigm. A cellular automaton (CA) based design scheme uses local update rules for both field variables (displacements) and design variables (lay-up configuration and laminate density measure) in an iterative fashion to convergence to an optimal design. In the present work, the displacements are updated based on the principle of local equilibrium and the design variables are updated according to the optimality criteria for minimum compliance design. A closed form displacement update rule for constant thickness isotropic continua is derived, while for the general anisotropic continua with variable thickness a numeric update rule is used. Combined lay-up and topology design of variable-stiffness flat laminates is performed under the action of in-plane loads and bending loads. An optimality criteria based formulation is used to obtain local design rules for minimum compliance design subject to a volume constraint. It is shown that the design rule splits into a two step application. In the first step an optimal lay-up configuration is computed and in the second step the density measure is obtained. The spatial lay-up design problem is formulated using both fiber angles and lamination parameters as design variables. A weighted average formulation is used to handle multiple load case designs. Numerical studies investigate the performance of the proposed design methodology. The optimal lay-up configuration is independent of the lattice density with more details emerging as the density is increased. Moreover, combined topology and lay-up designs are free of checkerboard patterns. The lay-up design problem is also solved using lamination parameters instead of the fiber orientation angles. The use of lamination parameters has two key features: first, the convexity of the minimization problem guarantees a global minimum; second, for both in-plane and bending problems it limits the number of design variables to four regardless of the actual number of layers, thereby simplifying the optimization task. Moreover, it improves the convergence rate of the iterative design scheme as compared to using fiber angles as design variables. Design parametrization using lamination parameters provides a theoretically better design, however, manufacturability of the designs is not certain. The cases of general, balanced symmetric, and balanced symmetric with equal thickness layers are studied separately. The feasible domain for laminates with equal thickness layers is presented for an increasing number of layers. A restricted problem is proposed that maintains the convexity of the design space for laminates with equal thickness layers. A recursive formulation for computing fiber angles for this case is also presented. On the computational side of the effort, a parallel version of the present CA formulation is implemented on message passing multiprocessor clusters. A standard parallel implementation does not converge for an increased number of processors. Detailed analysis revealed that the convergence problem is due to a Jacobi type iteration scheme, and a pure Gauss-Seidel type iteration through a pipeline implementation completely resolved the convergence problem. Timing results giving the speedup for the pipeline implementation were obtained for up to 260 processors. This work was supported by Grant NAG-1-01105 from NASA Langley Research Center. Special thanks to our project monitor Dr. Damodar R. Ambur for his technical guidance. / Ph. D.

<p> 49 beds of ripple-drift cross-lamination were measured in the Ordovician Cloridorme Formation of Gaspe, Quebec. Most of the beds are Bouma C (cross-laminated), some are BC (parallel lamination pas sing up into cross-lamination) and a few are AC and ABC types (graded bedding passing up into parallel and cross-lamination). </p> <p> Six climbing patterns have been recognised in the ripple-drift beds, namely: concave -upward, straight, sigmoidal, convex-upward, sinuous, and disconnected-irregular. Angles of climb range from 1 to 44 degrees. Commonly the angle of climb steepens up through the coset to about 1/2 or 3/4 of the coset thickness and then gradually flattens out until the bed is plane. </p> <p> Measurements of wave length, amplitude, stoss -angle, lee-angle, angle of climb and ratio of lee- to stoss-lamina thicknesses show that the wave length continues to increase upward, and the lee/stoss thickness ratio decreases upward through the coset. The amplitude, and stoss- and lee-angles increase upward through that portion of the coset in which the angle of climb increases upward. Simultaneously with the increase in amplitude and angle of climb, the shape of the foreset laminae becomes progressively more and more sigmoidal. </p> <p> Down-current changes in lamination types were recorded in several beds. The most interesting change is from parallel lamination down-current into ripple-drift, continuing downcurrent back into parallel lamination. </p> / Thesis / Master of Science (MSc)

No description available.

Dans cette thèse, nous nous s’intéressons au calcul des groupes de cohomologie de Dolbeault feuilletée H0∗L (M) de certaines laminations complexes. Ceci revient à résoudre le problème du ∂ le long des feuilles ∂Lα = ω. (Ici M est un espace métrique ou une variété dans le cas où L est un feuilletage F.) Trois situations ont été étudiées de manière explicite.1. Soit M = Ω un ouvert de C × R muni du feuilletage F dont les feuilles sont les sections Ωt = {z ∈ C : (z, t) ∈ Ω} ; on dira que F est le feuilletage canonique de Ω. Sous certaines conditions sur Ω et de croissance sur la forme feuilletée ω, nous montrons que l’´équation ∂Fα = ω a une solution.2. On se donne une suite (αn)n≥1 strictement croissante avec α1 = −1 et convergeant vers 1. Dans C × R on considère les points A = (0, 1) et An = (0, αn) pour n ≥ 1. Pour tout n ≥ 1, soient Sn la sphère de C × R de diamètre le segment [AnA] et E la réunion de toutes ces sphères. Alors E est un sous-espace métrique compact et connexe de C × R. Soit γ : E −→ E l’homéomorphisme défini par γ(w,u) = (ρn(w),u) lorsque (w, u) ∈ Sn où ρn est la rotation dans C d’angle 2πn. La suspension de γ donne une lamination complexe L dont les feuilles sont des surfaces de Riemann toutes équivalentes à C*. Pour cet exemple, nous montrons que l’espace vectoriel H01(L) est nul.3. On considère la variété M = C × Rn \ {(0, 0)} (les coordonnées d’un point seront notées (z,t)) qu’on munit du feuilletage complexe F défini par le système différentiel dt1 = • • • = dn = 0. Le difféomorphisme γ : (z, t) ∈ Mf7−→ (λz, λt) ∈ M (avec 0 < λ < 1) agit sur M de façon libre et propre ; en plus, c’est un automorphisme de F ; F induit alors sur le quotient M = M/γ (qui est difféomorphe `à Sn+1 × S1) un feuilletage complexe F par surfaces de Riemann. Nous montrons que les espaces vectoriels de cohomologie de Dolbeault feuilletée H00 F (M) et H01F (M) sont isomorphes à C. / In this thesis, we are interested in computing the foliated Dolbeault cohomology groups H0∗L (M) for some complex laminations. This amounts to solving the problem of the ∂ along the leaves ∂Lα = ω. (Here M is a metric space or a differentiable manifold if L is a foliation F.) Three situations were considered explicitly.1. Let M = Ω be an open set of C×R equipped with the foliation F whose leaves are the sections Ωt = {z ∈ C(z, t) ∈ Ω}; we say that F is the canonical foliation of Ω. Under certain conditions on Ω and growth conditions on the foliated form ω, we show that the equation ∂Fα = ω has a solution.2. Let (αn)n≥1 be a sequence of real numbers, strictly increasing with α1 = −1 and converging to 1. In C × R we consider the points A = (0, 1) and An = (0, αn) for n ≥ 1. For all n ≥ 1, let Sn be the sphere of C × R with a diameter segment [AnA] and E the union of all these spheres. Then E is a compact and connected subset of C × R. Let γ : E −→ E the homeomorphism defined by γ(w,u) = (ρn(w),u), where (w,u) ∈ Sn and ρn is the rotation in C with angle 2πn. The suspension of γ gives rise to a complex lamination L whose leaves are all equivalent Riemann surfaces isomorphic to C∗. For This example we show that the vector space H01 (L) is zero.3. Consider the manifold M = C × Rn \ {(0, 0)} (the coordinates of a point are denoted (z,t)) endowed with the complex foliation F defined by the differential system dt1 = • • • = dn = 0. The diffeomorphism γ : (z, t) ∈ M −→ (λz, λt) ∈ M (where 0 < λ < 1) acts on M freely and properly ; moreover it is an automorphism of the complex foliation F ; then F induces on the quotient M = M/γ (which is diffeomorphic to S n+1 × S1) a complex foliation F by Riemann surfaces. All leaves are isomorphic to C except one of them which is an elliptic curve. We show that the vector spaces H00 F (M) and H01F (M) of foliated Dolbeault cohomology are isomorphic to C.

I am creating this body of work based on how we as a society interact and utilize our every day valuable possessions. These would consist of personal items such as our keys, wallets and purses, As well as how well we are able to hide them from strangers, insofar as to where we personally choose to place them. It's interesting how many of us can be lackadaisical in this regard and as a result, many times don't carefully think about where we choose to place our valuable objects, until we lose them or worse, have them stolen.I am exploring the more thoughtful placement of these personal type possessions in our every day life, and how we have heretofore attempted to conceal them.

Based on experimentation with the steam bending of wood to curved shapes, this thesis describes my involvement with three basic aspects of the process. First is the procurement, assimilation, and construction of the equipment and apparatus necessary for the steam bending of wood. Secondly, the determination of certain qualities of particular woods in reference to steam bending is made. This includes: woods easily bent; woods not easily bent; the time required to plasticize stock; and the time required to set curves. Also noted are some of the physical limitations involved in bending stock with steam in the craftsman's studio. Thirdly, steam bent wood is related to furniture design in terms of the craftsman's approach to the design and to the problems inherent in this process.

The central nervous system is a complex, yet well-organised, often laminated, tissue. This robust organisation is evident in the architecture of the retina: consisting of 5 different neuronal types organised into distinct layers: Retinal Ganglion Cell (RGC), Amacrine Cell (AC), Bipolar Cell (BP), Horizontal Cell (HC) and Photoreceptor cell (PR) layers. This remarkable organisation is evolutionarily conserved in vertebrates, yet little is known about the mechanisms by which these cells form the correct layers. Live imaging has revealed overlapping periods of birth and extensive inter-digitation followed by cells sorting out into their appropriate positions, suggesting cell-cell interactions are important. To investigate possible cellular and molecular mechanisms responsible for the establishment of the tissue architecture I developed an organoid culture system for zebrafish retinal cells. To identify the cells in culture I used a Spectrum of Fates fish line which is a multiply transgenic line in which each retinal cell type can be identified based on expression of a combination of fluorescently tagged cell fate markers. The development of the protocol by which I cultured the cells and observed their cell-cell interactions involved establishing the best methods to dissociate and culture zebrafish retinal cells in a non-adhesive environment, then imaging the resulting reaggregates to examine the position of the different retinal cell types. By doing this I observed their inherent self-organising properties, in the absence of extrinsic cues or scaffolds. These cells appeared to be arranged in an inside-out layering, although all cell types are layered in the same relative order as they are in vivo. To analyse the organization in these aggregates I developed a Matlab script in collaboration with Leila Muresan which analyses the relative positioning of cells in concentric rings from the periphery to the centre of the aggregates according to the cell fate-tagged fluorescent markers. The script then fits this data as an empirical cumulative distribution function for different groups of cells to determine how spatially distinct populations of cells are. This gave me my measure of organisation. I then investigated the cell-cell interactions involved in this self-organisation by genetically or pharmacologically removing individual cell types and assaying the resulting organisation of the reaggregated, cell-type deficient, retinal organoids. I revealed that Müller Glia are important for retinal cell self-organisation. I also investigated the role of Retinal Pigment Epithelial (RPE) cells and Retinal Ganglion Cells and found they had no impact on the ability of the remaining cell types to organize. I began to investigate the role of Amacrine Cells but found that retinas void of ACs were susceptible to disaggregating in our dissection setup, preventing me from collecting the material needed for culture. I also investigated the role of candidate molecules in this system and revealed that R-Cognin is critical for retinal cells to reaggregate. Not only can I remove cells or molecules from the system, but I show how it can also be manipulated to replace molecules of interest such as laminin, by coating beads with the substance of choice and placing it amongst the cells to see if their organisational behaviour is affected. In summary, I have developed a system which provides a simple and easy platform to manipulate in various ways to help us potentially reveal some of the important players in neuronal patterning.

Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-06-07T16:03:19Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) 2011-Dissertaca-TiagoJoseFraga.pdf: 2508000 bytes, checksum: 353e13d59a7a766f83e7f95c17a6a54a (MD5) / Made available in DSpace on 2017-06-07T16:03:19Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) 2011-Dissertaca-TiagoJoseFraga.pdf: 2508000 bytes, checksum: 353e13d59a7a766f83e7f95c17a6a54a (MD5) Previous issue date: 2011-08-02 / Na indústria têxtil, o processo de lavagem e enxágüe são os que consomem a maior quantidade de água, e, conseqüentemente, os que geram a maior quantidade dos efluentes. Do ponto de vista ambiental, a indústria têxtil tem sido considerada de grande impacto, tendo em vista a descarga de grandes volumes de rejeitos contendo altas cargas de compostos e efluentes fortemente coloridos. Nesse trabalho é proposto um método de adsorção para a remoção dos corantes reativos Drimaren Azul, Vermelho e Dourado através de um adsorvente que consiste num resíduo beneficiado daindústria do alumínio. Busca-se assim, uma alternativa sustentável para as indústrias e lavanderias do agreste pernambucano. Foi realizado um planejamento fatorial 23de modo a determinar as condições ótimas de massa de adsorvente, temperaturae velocidade de agitação na remoção dos corantes. Depois de realizado o planejamento fatorial, foi proposto o teste cinético de modo a se determinar o tempo em que o sistema entra em equilíbrio para cada corante. Os estudos de equilíbrio foram realizados para que se obtivesse a isoterma de adsorção para cada corante e se realizasse a modelagem matemática, para a obtenção da constante de adsorção (KA) e da capacidade de adsorção máxima (qm). Os testes de termodinâmica de adsorção foram realizados de modo que se obtivessem os valores dos principais parâmetros termodinâmicos envolvidos no processo adsortivo para os três corantes estudados: Entalpia (ΔHº), Entropia (ΔSº) e Energia Livre de Gibbs (ΔGº). Os resultadosdo planejamento fatorialindicaramquea temperatura influencia negativamente no processo de adsorção dos três corantes, onde se obteve os melhores resultados a temperatura de 25ºC. Nos experimentos de cinética de adsorção, o corante Drimaren Azul atinge o equilíbrio a partir dos 5mincom q = 0,155mg∙g-1, o Drimaren Vermelho, a partir de 20min com q = 0,053mg∙g-1e o corante Drimaren Dourado, a partir de 5min com q = 0,059mg∙g-1.Os resultados de equilíbrio obtidos para os três corantes mostraram qm=6,192 mg∙g-1para o Drimaren Azul, qm= 0,262mg∙g-1para o Drimaren Vermelho e qm= 1,230mg∙g-1para o Drimaren Dourado.Foram realizados estudos de termodinâmicade adsorção para os corantes Drimaren Azul, Drimaren Vermelho e Drimaren Dourado seguindo as condições de 1,0g de adsorvente, velocidade de agitação de300rpm e tempo de contato de 10min. Foram avaliadas as curvas de equilíbrio nas temperaturas de 25ºC, 45ºC e 65ºC para os três corantes. Foram obtidos os resultados para os parâmetros termodinâmicos: ΔHº = 9,42 kJ∙mol-1ΔGº = 10,42 kJ∙mol-1e ΔSº = -4,40 10-3kJ∙mol-1, para o Drimaren Azul; ΔHº = 57,89 kJ∙mol-1ΔGº = 13,37 kJ∙mol-1e ΔSº = 1,40∙10-1kJ∙mol-1, para o Drimaren Vermelho; ΔHº = 4,72 kJ∙mol-1ΔGº = 11,95 kJ∙mol-1e ΔSº = -2,30 10-2kJ∙mol-1, para o Drimaren Dourado. / At the textile industry, the washing process and rinse are the ones which consumethe major amount of water, and, consequently, the ones which generate the major amount of effluents. By the environmental point of view, the textile industry has been considered of great impact, considering the huge reject volumes discharges, containing high charges of compounds and strongly coloured effluents (McKAY, 1979; CORREIA et al., 1994). The main concern in the environmental view point is about the removal of this effluents’ contaminants, which among them, the dyes are responsible for the major part. Achieve low costs for dye removal from the industrial wastewaters is the biggest challenge, once the social benefits are also inserted in this context. Some combined processes ensure a high efficiency on the removal percentagefor some dyes, such as the class of the reactive ones, indicating that the coagulation followed by adsorption is more efficient than it was made the adsorption before the coagulation process (LEE et al., 2006). In the present work, an adsorption method is proposed for the removal of the reactive dyes: Drimaren Blue, Red and Gold through an adsorbent consisting of a benefited residue from the aluminum industry. Search is thus, a sustainable alternative for the west Pernambuco’s laundry. A full factorial design was performed in order to determine the optimum conditions of adsorbent mass, pH and particle size on the dye removal. After the factorialdesign, it was proposed the kinetic study in order to determine the time in which the system achieve the equilibrium for each dye in thepresent work. The equilibrium tests were performed to obtain the adsorption isotherm for each dye and for the holding of the mathematical modeling, to obtain the adsorption Constant (KA) and the maximum adsorption capacity (qm). The adsorption thermodynamics experiments were performed in order to obtain the values of the main thermodynamic parameters involved on the adsorption process for the three dyes studied –Enthalpy (Hº), Entropy (Sº), and Gibbs’ Free Energy (Gº). The results of factorial design indicated that the temperature will negatively influence the adsorption of the three dyes, where we got the best resultsat 25 ° C.On the kinetic experiments, the Drimaren Blue dye reaches the equilibrium in 5 min, with q = 0,053 mg∙g-1and the Drimaren Red, in 20 min, withq = 0,053 mg∙g-1, the Drimaren Gold reaches the equilibrium in 5 min, with q = 0,059 mg∙g-1.The studies of thermodynamics of adsorption made for the Drimaren Blue, Drimaren Red and Drimaren Gold were conducted at the conditions of 1,0g of adsorbent, steering speed of 300rpm and 10min of contact time. The equilibrium curves were evaluated at the temperatures of 25ºC, 45ºC and 65ºC. The following results were obtained for the thermodynamics parameters: ΔHº = 9,42 kJ∙mol-1ΔGº = 10,42 kJ∙mol-1e ΔSº = -4,40 10-3kJ∙mol-1, for the Drimaren Blue; ΔHº = 57,89 kJ∙mol-1ΔGº = 13,37 kJ∙mol-1e ΔSº = 1,40∙10-1kJ∙mol-1, for the Drimaren Red; ΔHº = 4,72 kJ∙mol-1ΔGº = 11,95 kJ∙mol-1e ΔSº = -2,30 10-2kJ∙mol-1, for the Drimaren Gold.

This research project aimed to develop a condition monitoring system for the final production quality of pharmaceutical tablets and detection capping and lamination during powder compression process using the acoustic emission (AE) method. Pharmaceutical tablet manufacturers obliged by regulatory bodies to test the tablet's physical properties such as hardness, dissolution and disintegration before the tablets are released to the market. Most of the existing methods and techniques for testing and monitoring these tablet's properties are performed at the tablet post-compression stage. Furthermore, these tests are destructive in nature. Early experimental investigations revealed that the AE energy that is generated during powder compression is directly proportional to the peak force that is required to crush the tablet, i. e. crushing strength. Further laboratory and industrial experimental investigation have been conducted to study the relationship between the AE signals and the compression conditions. Traditional AE signal features such as energy, count, peak amplitude, average signal level, event duration and rise time were recorded. AE data analysis with the aid of advanced classification algorithm, fuzzy C-mean clustering showed that the AE energy is a very useful parameter in tablet condition monitoring. It was found that the AE energy that is generated during powder compression is sensitive to the process and is directly proportional to the compression speed, particle size, homogeneity of mixture and the amount of material present. Also this AE signal is dependent upon the type of material used as the tablet filler. Acoustic emission has been shown to be a useful technique for characterising some of the complex physical changes which occur during tabletting. Capping and lamination are serious problems that are encountered during tabletting. A capped or laminated tablet is one which no longer retains its mechanical integrity and exhibit low strength characteristics. Capping and lamination can be caused by a number of factors such as excessive pressure, insufficient binder in the granules and poor material flowabilities. However, capping and lamination can also occur randomly and they are also dependent upon the material used in tabletting. It was possible to identify a capped or laminated tablet by monitoring the AE energy level during continuous on-line monitoring of tabletting. Capped tablets indicated by low level of AE energy. The proposed condition monitoring system aimed to set the AE energy threshold that could discriminate between capped and non-capped tablets. This was based upon statistical distributions of the AE energy values for both the capped and non-capped tablets. The system aims to minimise the rate of false alarms (indication of capping when in reality capping has not occurred) and the rate of missed detection (an indication of non capping, when in reality capping has occurred). A novel approach that employs both the AE method and the receiver operating characteristic (ROC) curve was proposed for the on-line detection of capping and lamination during tabletting. The proposed system employs AE energy as the discriminating parameter to detect between capped and non-capped tablets. The ROC curve was constructed from the area under the two distributions of both capped and non-capped tablet. This curve shows a trade-off between the probabilities of true detection rate and false alarm rate for capped and non-capped tablet. A two-graph receiver operating characteristic (ROC) curve was presented as a modification of the original ROC curve to enable an operator to directly select the desired energy threshold for tablet monitoring. This plot shows the ROC co-ordinate as a function of the threshold value over the entire threshold (AE energy) range for all test outcomes. An alternative way of deciding a threshold based on the slope of the ROC curve was also developed. The slope of the ROC curve represents the optimal operating point on the curve. It depends upon the penalties cost of capping and the prevalence of capping. Sets of guidelines have been outlined for decision making i.e. threshold setting. These guidelines take into account both the prevalence of capping in manufacturing and the cost associated with various outcomes of tablet formation. The proposed condition monitoring system also relates AE monitoring to non-AE measurement as it enable an operator predicting tablet hardness and disintegration form the AE energy, a relationship which was established in this research.

This diploma thesis deals with recent methods of lightfastness evaluation of both classic and digitally printed photographs. It summarizes the experimental methods used for colour change measurements. Primarily, it studies an influence of additional protection on lightfastness enhancement. Lightfastness testing of colour prints was carried out by accelerated ageing. Samples were prepared by 3 types of inkjet printers and 3 different print media. The surface of photographs was left untreated or modified by varnishing or lamination. A set of samples, thus achieved, was used to monitor a print behaviour during the light exposure. In conclusion effects of used receiving layer, ink or additional surface treatment were discussed. Colour changes were evaluated on the basis of measured reflectance spectra from which colorimetric quantities were calculated. Results were processed using VolGa application. An actual print-life was calculated from the plot of the normalized gamut volume loss and the exposure.