A área de visualização volumétrica engloba um conjunto de técnicas utilizadas na representação, manipulação e exibição de dados associados à região de um volume, possibilitando, assim, a exploração e melhor compreensão do interior de objetos de natureza tridimensional. Contudo, algumas limitações ainda são encontradas nessa área, como, por exemplo, a exploração de mais de um valor simultaneamente em conjuntos de dados volumétricos multivariados. Além desse desafio, outro objeto de grande interesse da comunidade científica é a exploração de volumes variantes no tempo. A complexidade nesse caso está em tratar ou processar uma quantidade muito grande de dados buscando descobrir propriedades, estruturas ou características que variam com o tempo. O presente trabalho propõe técnicas e abordagens, baseadas no conceito de projeções multidimensionais, visando dar apoio à análise de conjuntos volumétricos multivariados que variam no tempo. A primeira técnica proposta, denominada Fastmap*, possibilitou a projeção de espaços de alta dimensionalidade em fluxo contínuo. A segunda técnica apresentada, denominada RLNP, permitiu a projeção de dados por vizinhança mantendo a coerência temporal nos dados projetados, além de possuir a capacidade de projetar espaços de alta dimensão com um nível de stressbaixo. Também, propomos uma abordagem para a análise baseada em atributos, denominada Scatter Projection, que facilita a exploração focada em um atributo específico junto com a similaridade dos dados entre eles. Finalmente, propõe-se uma abordagem baseada na reprojeção de agrupamentos usando técnicas de seleção de atributos para tentar identificar melhor as estruturas internas do volume. Assim, o presente trabalho contribui no sentido de levantar e discutir limitações das técnicas disponíveis, e em seguida, buscar possibilidades de solução para tais questões, propondo técnicas e abordagens que possibilitam a exploração de grandes conjuntos de dados volumétricos multivariados, mantendo a coerência temporal / The area of volume visualization encompasses a set of techniques used for representation, manipulation and display of data associated with a region of a volume, thus enabling the exploration and understanding of the interior of three-dimensional objects. However, some limitations are still encountered in this area. For example, the simultaneous exploration of more than one value in multivariate volumetric datasets. Beyond this challenge, another issue of great interest to the scientific community is the exploration of time-varying volumes. The complexity of this case lies in treatment or processing of a very large amount of data, seeking to discover properties, structures, or characteristics that may vary in time. This work proposes techniques and approaches, based on the concept of multidimensional projections, in order to support multivariate volumetric analysis of time varying data sets. The first technique proposed, called Fastmap*, enables the projection of high dimensional streaming data. The second technique presented, called Recursive Laplacian-based Neiboorhood Projection, allows the projection of data sets based on neighborhoods, maintaining the temporal coherence in the projected data, besides having the ability to project highdimensional spaces with a low level of stress. Also, we propose an approach for the analysis of specific attributes, referred to as Scatter Projection, which facilitates the exploration focused on a specific attribute and on the similarity between them. Finally, we propose an approach based on reprojection of groups using feature selection techniques for better identification of internal structures of the volume. Thus, this study contributes towards surveying and discussing limitations of the area, and then seeks ways of solving these issues, proposing techniques and approaches that enable the exploration of multidimensional volumetric time varying data sets, maintaining the temporal coherence

Volumetric muscle loss (VML) is a debilitating injury which results in full or partial loss of function. Current clinical options utilize tissue grafts and bracing to restore function. Tissue graft implantation oftentimes leads to serious complications, some of which end in graft rejection and thereby necessitate further surgeries and procedures. Polymeric scaffolds show promise as scaffolding systems due to their mechanical properties and overall degradation profiles. Scaffolds need appropriate mechanical properties, 10-60 kPa modulus, and overall degradation times, five days to two weeks, to initiate tissue regeneration. Poly(β-amino ester)s (PBAE), a class of synthetic polymers, act as a safe biocompatible material with overall degradation times that are suitable for healing; however, due to harmful ultraviolet light (UV) irradiation from common crosslinking methods, these scaffold systems cannot be synthesized in vivo. This research presents the development and characterization of blue light (BL) crosslinked PBAEs. BL PBAEs showed vastly higher swelling ratios, 300-400% increase; decreased mechanical strength, an average decrease of 877 kPa in compressive modulus and 431 kPa in tensile modulus; and prolonged degradation patterns, 22% average mass retention. BL PBAEs show mechanical properties and degradation profiles that could be used as a skeletal muscle scaffolds.

Master of Science in Dentistry / Objectives: The aims of this study were: • to evaluate the exact level of the mandibular canal using Cone Beam Volumetric Tomography (CBVT) using measurements taken on images from the NewTom3G and i-CAT machines and manually • to determine the course of the mandibular canal in the regions of the first, second , and third molars • to compare the course of the mandibular canals bilaterally • to compare variables measured between the CBVT and panoramic units • to determine appropriate positions for the implant placement at the region of the mandibular molars in relation to the mandibular canal. Methods: Ten mandibles were selected, including seven edentulous and three dentate ones. They were marked at four positions from the distal border of the mental foramina in the posterior direction at intervals of 10.00 mm. On each dry mandible, at four sites namely M0, M1, M2, and M3, Gutta Percha (GP) points, known as markers, were attached to the mandible so that they were parallel to the midline of the mandible on both buccal and lingual sides. On the NewTom 3G and i-CAT, variables of cross-sectional images were measured from the alveolar crest of the mandible to the superior border of the mandibular canal (AC); the lingual rim of the canal to the lingual margin of the mandible (LC); the buccal rim of the canal to the buccal margin of the mandible (BC); the inferior rim of the canal to the lower border of the mandible (IC), and from the lingual margin to the buccal margin of the mandible (BW: Bone Width). Dry mandibles were subsequently sacrificed by cutting at the four marked sites. On each cross-section of mandibles, distances AC, BC, LC, IC, and BW were measured using a caliper as the manual measurement. IC distances on a conventional OrthophosIII panoramic machine were also measured to compare with the CBVT. Data were managed by Microsoft Office Excel 2003 and transferred to the software of Statistics Package for Social Sciences (SPSS) version 15.0 for Windows for analysis. Data were presented as Mean, Standard Deviation (SD), and Mean Difference, and Standard Error of Mean (SEM) with decimal at 0.00. T-test and One-way ANOVA were used to analyse variables measured in which T-test was used to analyse variables with paired samples and One-way ANOVA was used with adjustment for multiple comparisons of Bonferroni. Statistical significance has an assumed P- value of 0.05 or less. Results: The findings showed that there was no significant difference among measured variables from the NewTom 3G, i-CAT and manual measurement (P>0.05). There was significant statistical difference between the Orthophos OPG machine and CBVT system (P=0.00<0.05). There was no significant difference in the course of the mandibular canals bilaterally (P>0.05). On average, Distances AC, BC, LC, and IC were obtained for reference purposes. The bone width of the mandible on the right side was slightly different from that on the left side. Conclusions: The findings implied CBVT was an accurate diagnostic tool for locating the course of the mandibular canal and for placing dental implants in the region of the mandibular molars. The course of the mandibular canal on the left and right sides was variable. The distances measured at the region of the first, second, and third mandibular molars should be considered as a valuable reference. The bone width of the mandible on the right and left sides was slightly different. The accuracy of the NewTom3G and i-CAT was superior to the panoramic Orthophos machine. However, a panoramic radiograph is still valuable in the daily dental clinic.

A volumetric contact dynamics model has been proposed by Gonthier et al. [1, 2, 3] for the purpose of rapidly generating reliable simulations of space-based manipulator contact dynamics. By assuming materials behave as a Winkler elastic foundation model, forces and moments between two bodies in contact can be expressed in terms of the volume of interference between the undeformed geometries of the bodies. Friction between bodies is modelled by a dwell-time dependent bristle model for both tangential friction, and spinning friction torque. This volumetric model has a number of advantages. Unlike point-contact models, it allows for the modelling of contact between complex geometries and scenarios where the contact surface is relatively large, while being less computationally expensive than finite element methods. Rolling resistance is included in the model through damping effects across the volume of interference. The friction model accounts for dwell-time dependent slip-stick effects, spinning friction torque, and the Contensou effect. In this thesis, an experimental validation of the volumetric contact model is presented for the first time. Models for simple geometries in contact (e.g. cylinder-on-plane, sphere-on-plane) have been developed for stationary contact and for contact with motion normal and tangential to the contact surface. Tangential motion is modelled with pure translation, pure rotation about the normal axis, and combined motion, in order to separately consider friction forces, spinning friction torque, and the Contensou effect, respectively. An apparatus has been developed to experimentally validate these models for metal-on-metal contact. The apparatus has two configurations, one for validating the normal contact models and the other for the friction models. Experimental measurements of forces and displacements are used to identify model parameters (e.g. volumetric stiffness, friction coefficients, etc.). For normal force experiments, modelling the contact forces as proportional to volume of interference was found to be a reasonable approximation. A Hertzian model was compared with the volumetric model for spherical payloads loaded quasi-statically. Using stiffnesses estimated from spherical experiments, small misalignments of the cylindrical payloads were estimated that corresponded well with measured results. Dynamic experiments suggest an inverse relationship between impact velocity and the hysteretic damping coefficient. The high normal forces applied in the friction experiments were found to create significant wear on the contact surfaces. Coefficients of friction between titanium and aluminum were found to be consistent translationally and rotationally. Friction forces from combined translation and rotation demonstrate that the Contensou effect is accurately described by the volumetric contact model.

Advances in computational power have produced great strides in the later design and production portions of an aircraft s life cycle, and these advances have included the internal layout component of the design and manufacturing process. However, conceptual and preliminary design tools for internal layout remain primarily based on historical regressions and estimations a situation that becomes untenable when considering revolutionary designs or component technologies. Bringing internal layout information forward in the design process can encourage the same level of benefits enjoyed by other disciplines as advances in aerodynamics, structures and other fields propagate forward in the design of complex systems. Accurate prediction of the volume required to contain all of an aircraft s internal components results in a more accurate prediction of aircraft specifications, mission effectiveness, and costs, helping determine if an aircraft is the best choice for continued development. This is not a computationally simple problem, however, and great care must be taken to ensure the efficiency of any proposed solution. Any solution must also address the uncertainty inherent in describing internal components early in the design process. Implementing a methodology that applies notions of an intelligent search for a solution, as well as deals robustly with component sizing, produces a high chance of success. Development of a robust, rapid method for assessing the volumetric characteristics of an aircraft in the context of the conceptual and preliminary design processes can offer many of the benefits of a complete internal layout without the immense assignment of resources typical in the detail phase of the design process. A simplified methodology for volumetrically sizing an aircraft is presented here as well as an assessment of the state-of-the-art techniques for volumetric considerations used in current aircraft design literature. A prototype tool using a combination of original code and publicly available libraries is developed and explored. A sample aircraft design is undertaken with the prototype tool to demonstrate the effectiveness of the methodology.

Acid fracturing stimulation is one of the preferred methods to improve well productivity in carbonate reservoirs. Acid is injected into the fractured zone after a starter fracture is created in the near wellbore area by viscous fluid (pad). This results in propagation of a two-wing crack away from the perforations with simultaneous dissolution etching of the created surfaces. If the created etched surface is non-uniform, then after the treatment ends and the fracture face closes, a high conductivity path may remain in the formation, connected to the well. The important factors controlling the effectiveness of acid fracturing are the etched-fracture penetration and conductivity. In this research, I use the distributed volumetric sources (DVS) method to calculate gas production from a well stimulated by acid fracturing. The novel concept realized in this research is that, during the production process, the conductivity of the acid created fracture changes. I use the Nierode - Kruk correlation to describe this effect as a function of effective closure stress that in turn is determined from the flowing bottomhole pressure and minimum horizontal stress. By combining the well productivity calculation from the DVS method taking into account varying fracture conductivity with gas material balance, I obtain an improved model of gas production. The model is then used to not only forecast production from acid fractured wells but also to evaluate the known production history of such wells. Based on the concepts discussed above, I have developed a program called "Gas Acid" which is useful to optimize acid fracturing treatments and also suitable to infer created fracture parameters from known production history. The "Gas Acid" program has been validated with data from two Saudi Aramco gas wells. It was found that the production forecast obtained from the "Gas Acid" program matches the actual production history with reasonable accuracy and the remaining discrepancy could be resolved by taking into account refinement of the material balance. The refinement became necessary, because the "Gas Acid" program was developed for dry gas but the reservoir fluids in the field examples were classified as retrograde gas and wet gas. When accounting for the additional mass of gas "hidden" in the produced condensate, the match of forecast and actual data was improved considerably.

Thesis (Ph. D.)--Columbia University, 1933. / Vita. Bibliography: p. 38-39.

Researchers have long been interested in the role of the corpus callosum in reading disorder, but existing studies have yielded inconsistent results. Some have found larger corpus callosa in those with reading disorder, others have found smaller corpus callosa, and some have found no differences in the corpus callosa of persons with and without reading disability. Some possible problems with past studies include failure to control for whole brain size, intelligence, gender, lateral dominance, and the presence of other syndromes such as Attention Deficit Hyperactivity Disorder. The current study is an examination of the corpus callosum in 68 readers nested in 24 families. Data were centered around the family mean so that the variance within families could be determined. Corpus callosum volumes were measured and controlled for whole brain volume, intelligence, and gender. A series of regressions were used to determine whether the volume of the corpus callosum significantly contributed to the variance in oral reading, phonological processing, and rapid naming. The midsagittal slice was segmented into fifths, and similar regressions were performed. A logistic regression was used to determine whether variation in corpus callosum volume could predict RD and no RD group membership. Finally, left and right volumes were compared and a correlation between corpus callosum volume and area at the midsagittal slice were conducted. Results suggest that better readers within families have larger corpus callosum areas in the midsagittal slice at the midbody. Better phonological processors within families had smaller corpus callosum volumes, but a problem with restricted range for phonological processing scores renders this finding unreliable. Rapid naming scores appear to be unrelated to the corpus callosum in this sample. Differences in the corpus callosum are not robust enough to predict diagnostic group and there appears to be no differences between left and right hemisphere volumes of the corpus callosum. Measurements of area at the midsagittal slice are highly correlated with the volumetric measurements suggesting that for subsequent studies, area at the midsagittal slice may be sufficient. / text

Submitted in fulfillment of the academic requirements for the Masters Degree in Technology: Chemistry, Durban University of Technology, 2008. / The thermodynamic properties of binary liquid mixtures involving ionic liquids (ILs) with alcohols were determined. ILs are an important class of solvents since they are being investigated as environmentally benign solvents, because of their negligible vapour pressure, and as potential replacement solvents for volatile organic compounds (VOCs) currently used in industries. Alcohols were chosen for this study because they have hydrogen bonding and their interaction with ILs will help in understanding the intermolecular interactions. Also, their thermodynamic properties are used for the development of specific chemical processes. The excess molar volumes of binary mixtures of {1-ethyl-3-methylimidazolium ethylsulfate + methanol or 1-propanol or 2-propanol}, {trioctylmethylammonium bis (trifluoromethyl-sulfonyl) imide + methanol or ethanol or 1-propanol}, {1-buty-3-methylimidazolium methylsulfate + methanol or ethanol or 1-propanol} were calculated from experimental density values, at T = (298.15, 303.15 and 313.15) K. The Redlich-Kister smoothing polynomial was fitted to the excess molar volume data. The partial molar volumes of the binary mixtures {1-ethyl-3-methylimidazolium ethylsulfate + methanol or 1-propanol or 2-propanol}, {trioctylmethylammonium bis (trifluoromethyl-sulfonyl) imide + methanol or ethanol or 1-propanol}, {1-buty-3-methylimidazolium methylsulfate + methanol or ethanol or 1-propanol} were calculated from the Redlich-Kister coefficients, at T = (298.15, 303.15 and 313.15) K. This information was used to better understand the intermolecular interactions with each solvent at infinite dilution. iii The isentropic compressibility of {trioctylmethylammonium bis (trifluoromethyl-sulfonyl) imide + methanol or ethanol or 1-propanol}, were calculated from the speed of sound data at T = 298.15 K.

We explore the integration of projected imagery with a physical book that acts as a tangible interface to multimedia data. Using a camera and projector pair, a tracking framework is presented wherein the 3D position of planar pages are monitored as they are turned back and forth by a user, and data is correctly warped and projected onto each page at interactive rates to provide the user with an intuitive mixed-reality experience. The book pages are blank, so traditional camera-based approaches to tracking physical features on the display surface do not apply. Instead, in each frame, feature points are independently extracted from the camera and projector images, and matched to recover the geometry of the pages in motion. The book can be loaded with multimedia content, including images and videos. In addition, volumetric datasets can be explored by removing a page from the book and using it as a tool to navigate through a virtual 3D volume.